WorldWideScience

Sample records for activity knee motion

  1. Ambulatory measurement of knee motion and physical activity: preliminary evaluation of a smart activity monitor

    Malchau Henrik

    2006-09-01

    Full Text Available Abstract Background There is currently a paucity of devices available for continuous, long-term monitoring of human joint motion. Non-invasive, inexpensive devices capable of recording human activity and joint motion have many applications for medical research. Such a device could be used to quantify range of motion outside the gait laboratory. The purpose of this study was to test the accuracy of the modified Intelligent Device for Energy Expenditure and Activity (IDEEA in measuring knee flexion angles, to detect different physical activities, and to quantify how often healthy subjects use deep knee flexion in the ambulatory setting. Methods We compared Biomotion Laboratory (BML "gold standard" data to simultaneous IDEEA measures of knee motion and gait, step up/down, and stair descent in 5 healthy subjects. In addition, we used a series of choreographed physical activities outside the BML to confirm the IDEEA's ability to accurately measure 7 commonly-performed physical activities. Subjects then continued data collection during ordinary activities outside the gait laboratory. Results Pooled correlations between the BML and IDEEA knee flexion angles were .97 +/- .03 for step up/down, .98 +/- .02 for stair descent, and .98 +/- .01 for gait. In the BML protocol, the IDEEA accurately identified gait, but was less accurate in identifying step up/down and stair descent. During sampling outside the BML, the IDEEA accurately detected walking, running, stair ascent, stair descent, standing, lying, and sitting. On average, subjects flexed their knees >120° for 0.17% of their data collection periods outside the BML. Conclusion The modified IDEEA system is a useful clinical tool for evaluating knee motion and multiple physical activities in the ambulatory setting. These five healthy subjects rarely flexed their knees >120°.

  2. Complementary limb motion estimation for the control of active knee prostheses.

    Vallery, Heike; Burgkart, Rainer; Hartmann, Cornelia; Mitternacht, Jürgen; Riener, Robert; Buss, Martin

    2011-02-01

    To restore walking after transfemoral amputation, various actuated exoprostheses have been developed, which control the knee torque actively or via variable damping. In both cases, an important issue is to find the appropriate control that enables user-dominated gait. Recently, we suggested a generic method to deduce intended motion of impaired or amputated limbs from residual human body motion. Based on interjoint coordination in physiological gait, statistical regression is used to estimate missing motion. In a pilot study, this complementary limb motion estimation (CLME) strategy is applied to control an active knee exoprosthesis. A motor-driven prosthetic knee with one degree of freedom has been realized, and one above-knee amputee has used it with CLME. Performed tasks are walking on a treadmill and alternating stair ascent and descent. The subject was able to walk on the treadmill at varying speeds, but needed assistance with the stairs, especially to descend. The promising results with CLME are compared with the subject's performance with her own prosthesis, the C-Leg from Otto Bock.

  3. Older Adults without Radiographic Knee Osteoarthritis: Knee Alignment and Knee Range of Motion

    Lissa Fahlman; Emmeline Sangeorzan; Nimisha Chheda; Daphne Lambright

    2014-01-01

    This study describes knee alignment and active knee range of motion (ROM) in a community-based group of 78-year old adults (n = 143) who did not have radiographic evidence of knee osteoarthritis in either knee (KL 0.001) than women with varus or...

  4. Development of a knee joint motion simulator to evaluate deep knee flexion of artificial knee joints.

    Takano, Y; Ueno, M; Kiguchi, K; Ito, J; Mawatari, M; Hotokebuchi, T

    2008-01-01

    A purpose of this study is to examine the effect that quadriceps femoris force gives to rotation angle and joint reaction force of total knee prosthesis during deep knee flexion such as a unique sitting style called 'seiza' in Japanese. For the evaluation, we developed the knee motion simulator which could bend to 180 degrees continually simulating the passive flexion performed by clinicians. A total knee prosthesis, which is a specially-devised posterior stabilized type and capable of flexion up to 180 degrees, was inserted into bone model. And this prosthesis pulled by three kinds of quadriceps femoris forces to perform parameter study. The results obtained in this study were showed the same tendency with those in the past cadaveric experiment. It is suggested that the rotation angle and joint reaction force of total knee prosthesis are affected by shape of prosthesis, a vector of quadriceps femoris force, and bony aliments during deep knee flexion.

  5. [Effectiveness of continuous passive motion after total knee replacement].

    Trzeciak, Tomasz; Richter, Magdalena; Ruszkowski, Krzysztof

    2011-01-01

    Continuous passive motion (CPM) is frequently used method in the early post-operative rehabilitation in patients after knee surgery. Aim of this study was to evaluate the effectiveness of CPM after primary total knee arthroplasty. Efficacy was assesed in terms of clinical score and functional recovery. 93 patients (101 knee joints) undergoing total knee replacement were assigned into two groups. The experimental group received continuous passive motion and active exercises. A control group received conventional physical therapy only. CPM was initiated in the first day after surgery, for 120 minutes, starting with 0-40 degrees range of motion, increased as tolerated (mean 10 degrees per day) and maintained during the hospital stay. Outcome measures were those included in Knee Society Score (KSS). Functional recovery was evaluated using WOMAC. All subjects were evaluated once before the surgery and on 10th day postoperatively. Mean clinical score (KSS) at the day 10 was 70 +/- 15 points in the experimental group and 74 +/- 12 in a control group. There were no statistical difference between the two groups for any outcome measures. CPM group mean range of motion was 83 degrees +/- 14 degrees and a group without CPM 77 degrees +/- 21 degrees. KSS functional score was 66 +/- 9 points in the experimental group compared to 62 +/- 7 points in a control group. Subjective estimation of pain level, joint stiffness and function showed no statistical difference between the two groups regarding total and subscale scores. Mean total score was 24 +/- 19 points in the CPM group and 22 +/- 17 in a group without CPM. These findings show that CPM had no significant advantage in terms of improving clinical measurements. However, there was beneficial effect on subjective assessment of pain level, joint stiffness and functional ability.

  6. Does knee motion contribute to feet-in-place balance recovery?

    Cheng, Kuangyou B

    2016-06-14

    Although knee motions have been observed at loss of balance, the ankle and hip strategies have remained the focus of past research. The present study aimed to investigate whether knee motions contribute to feet-in-place balance recovery. This was achieved by experimentally monitoring knee motions during recovery from forward falling, and by simulating balance recovery movements with and without knee joint as the main focus of the study. Twelve participants initially held a straight body configuration and were released from different forward leaning positions. Considerable knee motions were observed especially at greater leaning angles. Simulations were performed using 3-segment (feet, shanks+thighs, and head+arms+trunk) and 4-segment (with separate shanks and thighs segments) planar models. Movements were driven by joint torque generators depending on joint angle, angular velocity, and activation level. Optimal joint motions moved the mass center projection to be within the base of support without excessive joint motion. The 3-segment model (without knee motions) generated greater backward linear momentum and had better balance performance, which confirmed the advantage of having only ankle/hip strategies. Knee motions were accompanied with less body angular momentum and a lower body posture, which could be beneficial for posture control and reducing falling impact, respectively.

  7. Patella Eversion Reduces Early Knee Range of Motion and Muscle Torque Recovery after Total Knee Arthroplasty: Comparison between Minimally Invasive Total Knee Arthroplasty and Conventional Total Knee Arthroplasty

    Tokifumi Majima

    2011-01-01

    Full Text Available We hypothesized that patella eversion during total knee arthroplasty (TKA reduces early return of active knee extension and flexion, quadriceps muscle strength, and postoperative pain. In 100 conventional TKA knees and 100 minimally invasive TKA (MIS TKA knees, we compared knee range of motion (ROM, postoperative pain, and quadriceps muscle strength at 1 day, 4 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 12 weeks, 1 year, and 5 years after surgery. The differences of surgical approach between MIS TKA and conventional TKA of this study are length of skin incision with subcutaneal flap and patella eversion. In MIS TKA, skin incision is shorter than conventional TKA. Furthermore, patella is not everted in MIS TKA procedure. There were no significant differences in preoperative factors. Postoperative improvement of ROM, postoperative muscle strength recovery, and postoperative improvement of visual analog scale were faster in patients with MIS TKA when compared to that in patients with conventional TKA. On the other hand, no significant difference was observed in complication, 5-year clinical results of subjective knee function score, and the postoperative component angle and lower leg alignment. These results indicate that patella eversion may affect muscle strength recovery and postoperative pain.

  8. Improvements in knee biomechanics during walking are associated with increased physical activity after total knee arthroplasty.

    Arnold, John B; Mackintosh, Shylie; Olds, Timothy S; Jones, Sara; Thewlis, Dominic

    2015-12-01

    Total knee arthroplasty (TKA) in people with knee osteoarthritis increases knee-specific and general physical function, but it has not been established if there is a relationship between changes in these elements of functional ability. This study investigated changes and relationships between knee biomechanics during walking, physical activity, and use of time after TKA. Fifteen people awaiting TKA underwent 3D gait analysis before and six months after surgery. Physical activity and use of time were determined in free-living conditions from a high resolution 24-h activity recall. After surgery, participants displayed significant improvements in sagittal plane knee biomechanics and improved their physical activity profiles, standing for 105 more minutes (p=0.001) and performing 64 min more inside chores on average per day (p=0.008). Changes in sagittal plane knee range of motion (ROM) and peak knee flexion positively correlated with changes in total daily energy expenditure, time spent undertaking moderate to vigorous physical activity, inside chores and passive transport (r=0.52-0.66, p=0.005-0.047). Restoration of knee function occurs in parallel and is associated with improvements in physical activity and use of time after TKA. Increased functional knee ROM is required to support improvements in total and context specific physical activity.

  9. Recognizing knee pathologies by classifying instantaneous screws of the six degrees-of-freedom knee motion.

    Wolf, Alon; Degani, Amir

    2007-05-01

    We address the problem of knee pathology assessment by using screw theory to describe the knee motion and by using the screw representation of the motion as an input to a machine learning classifier. The flexions of knees with different pathologies are tracked using an optical tracking system. The instantaneous screw parameters which describe the transformation of the tibia with respect to the femur in each two successive observation is represented as the instantaneous screw axis of the motion given in its Plücker line coordinates along with its corresponding pitch. The set of instantaneous screw parameters associated with a particular knee with a given pathology is then identified and clustered in R(6) to form a "signature" of the motion for the given pathology. Sawbones model and two cadaver knees with different pathologies were tracked, and the resulting screws were used to train a classifier system. The system was then tested successfully with new, never-trained-before data. The classifier demonstrated a very high success rate in identifying the knee pathology.

  10. [Recovery from total knee arthroplasty through continuous passive motion].

    Sánchez Mayo, B; Rodríguez-Mansilla, J; González Sánchez, B

    2015-01-01

    The purpose of this study was to know the effects of continuous passive mobilization in patients who underwent total knee arthroplasty. A search strategy was developed to retrieve all clinical trials, written in English and/or Spanish, published in the electronic search databases PubMed, Cochrane Library Plus, Dialnet, CSIC and PEDro. The inclusion criteria were: clinical trials published from January 2000 until November 2014 in English or Spanish. Out of 537 clinical trials that were potentially relevant, a total of 12 were included in this review. The evaluation of 1,153 patients shows that there is no significant difference in improving the range of the joint, pain, balance, motion, healing and hospital stay using continuous passive mobilization against the regular physiotherapy treatment for total knee arthroplasty. The application of continuous passive mobilization in the long-term does not provide any benefit in terms of the breadth of the range of the joint, pain and improvement of standing and motion in comparison with conventional postoperative physiotherapy treatment in total knee arthroplasty. In the short term an improvement is obtained in the range of joint motion in knee flexion.

  11. EFFECTS OF KINESIOTAPING ALONG WITH QUADRICEPS STRENGTHENING EXERCISES ON PAIN, JOINT RANGE OF MOTION AND FUNCTIONAL ACTIVITIES OF KNEE IN SUBJECTS WITH PATELLOFEMORAL OSTEOARTHRITIS

    M. Harshitha

    2014-08-01

    Full Text Available Background: Patello femoral Osteoarthritis is the most common degenerative disease in older age group, causing pain, physical disability, and decreased quality of life.As many treatment options available, kinesiotaping is an efficacious treatment for management of pain & disability in patellofemoral joint osteoarthritis. Previous studies have shown that kinesiotaping as well as quadriceps strengthening significantly yields functional benefits. But there is lack of evidence revealing combined effectiveness & effects of kinesiotaping along with quadriceps strengthening in subjects with patellofemoral joint osteoarthritis. Methods: 30 subjects with symptoms of patellofemoral osteoarthritis fulfilled the inclusion criteria were randomly assigned into 2 groups of 15 in each group. Taping along with quadriceps strengthening program is compared to the quadriceps strengthening program alone. Pain were measured by Visual Analogue Scale (VAS, knee ROM were measured by Goniometer, Functional status were measured by Western Ontario McMaster Universities index (WOMAC, score. Measurements were taken pre & post intervention. Results: The results indicated that kinesiotaping along with quadriceps strengthening exercises showed there was statistically significant improvement in pain (<0.05, knee ROM (<0.05 and functional activities (<0.05 after 6 weeks compared to quadriceps strengthening alone. Conclusion: Subjects with kinesiotaping along with quadriceps strengthening showed significant improvement in reducing pain, in improving ROM & functional activities at the end of 6th week treatment when compared to subjects with patellofemoral osteoarthritis underwent quadriceps strengthening exercises alone.

  12. Data Collection and Analysis Using Wearable Sensors for Monitoring Knee Range of Motion after Total Knee Arthroplasty

    Chiang, Chih-Yen; Chen, Kun-Hui; Liu, Kai-Chun; Hsu, Steen Jun-Ping; Chan, Chia-Tai

    2017-01-01

    Total knee arthroplasty (TKA) is the most common treatment for degenerative osteoarthritis of that articulation. However, either in rehabilitation clinics or in hospital wards, the knee range of motion (ROM) can currently only be assessed using a goniometer. In order to provide continuous and objective measurements of knee ROM, we propose the use of wearable inertial sensors to record the knee ROM during the recovery progress. Digitalized and objective data can assist the surgeons to control the recovery status and flexibly adjust rehabilitation programs during the early acute inpatient stage. The more knee flexion ROM regained during the early inpatient period, the better the long-term knee recovery will be and the sooner early discharge can be achieved. The results of this work show that the proposed wearable sensor approach can provide an alternative for continuous monitoring and objective assessment of knee ROM recovery progress for TKA patients compared to the traditional goniometer measurements. PMID:28241434

  13. Active knee joint flexibility and sports activity

    Hahn, Thomas; Foldspang, Anders; Vestergaard, E

    1999-01-01

    was significantly higher in women than in men and significantly positively associated with weekly hours of swimming and weekly hours of competitive gymnastics. Active knee flexion was significantly positively associated with participation in basketball, and significantly negatively associated with age and weekly...

  14. Knee Flexion and Daily Activities in Patients following Total Knee Replacement: A Comparison with ISO Standard 14243

    Markus A. Wimmer

    2015-01-01

    Full Text Available Walking is only one of many daily activities performed by patients following total knee replacement (TKR. The purpose of this study was to examine the hypotheses (a that subject activity characteristics are correlated with knee flexion range of motion (ROM and (b that there is a significant difference between the subject’s flexion/extension excursion throughout the day and the ISO specified input for knee wear testing. In order to characterize activity, the number of walking and stair stepping cycles, the time spent with dynamic and stationary activities, the number of activity sequences, and the knee flexion/extension excursion of 32 TKR subjects were collected during daily activity. Flexion/extension profiles were compared with the ISO 14243 simulator input profile using a level crossing classification algorithm. Subjects took an average of 3102 (range: 343–5857 walking cycles including 65 (range: 0–319 stair stepping cycles. Active and passive ROMs were positively correlated with stair walking time, stair step counts, and stair walking sequences. Simulated knee motion according to ISO showed significantly fewer level crossings at the flexion angles 20–40° and beyond 50° than those measured with the monitor. This suggests that implant wear testing protocols should contain more cycles and a variety of activities requiring higher knee flexion angles with incorporated resting/transition periods to account for the many activity sequences.

  15. Dynamic Finite Element Analysis of Mobile Bearing Type Knee Prosthesis under Deep Flexional Motion

    Mohd Afzan Mohd Anuar

    2014-01-01

    Full Text Available The primary objective of this study is to distinguish between mobile bearing and fixed bearing posterior stabilized knee prostheses in the mechanics performance using the finite element simulation. Quantifying the relative mechanics attributes and survivorship between the mobile bearing and the fixed bearing prosthesis remains in investigation among researchers. In the present study, 3-dimensional computational model of a clinically used mobile bearing PS type knee prosthesis was utilized to develop a finite element and dynamic simulation model. Combination of displacement and force driven knee motion was adapted to simulate a flexion motion from 0° to 135° with neutral, 10°, and 20° internal tibial rotation to represent deep knee bending. Introduction of the secondary moving articulation in the mobile bearing knee prosthesis has been found to maintain relatively low shear stress during deep knee motion with tibial rotation.

  16. Is latero-medial patellar mobility related to the range of motion of the knee joint after total knee arthroplasty?

    Ota, Susumu; Nakashima, Takeshi; Morisaka, Ayako; Omachi, Takaaki; Ida, Kunio; Kawamura, Morio

    2010-12-01

    Diminished range of motion (ROM) of the knee joint after total knee arthroplasty (TKA) is thought to be related to reduced patellar mobility. This has not been confirmed clinically due to a lack of quantitative methods adequate for measuring patellar mobility. We investigated the relationship between patellar mobility by a reported quantitative method and knee joint ROM after TKA. Forty-nine patients [osteoarthritis--OA: 29 knees; rheumatoid arthritis--RA: 20 knees] were examined after TKA. Respective medial and lateral patellar mobility was measured 1 and 6 months postoperatively using a patellofemoral arthrometer (PFA). Knee joint ROM was also measured in each of those 2 sessions. Although the flexion and extension of the knee joints improved significantly from 1 to 6 months after TKA, the medial and lateral patellar displacements (LPDs) failed to improve during that same period. Moreover, only the changes in knee flexion and medial patellar displacement (MPD) between the two sessions were positively correlated (r = 0.31, p knee ROM after TKA.

  17. Clinically assessed mediolateral knee motion: impact on gait

    Thorlund, Jonas Bloch; Creaby, Mark W; Simic, Milena;

    2011-01-01

    Mediolateral knee movement can be assessed visually with clinical tests. A knee-medial-to-foot position is associated with an increased risk of knee injuries and pathologies. However, the implications of such findings on daily tasks are not well understood. The aim of this study was to investigate...... if a knee-medial-to-foot position assessed during a clinical test was associated with altered hip and knee joint kinematics and knee joint kinetics during gait compared with those with a knee-over-foot position....

  18. Quantifying the Consistency of Wearable Knee Acoustical Emission Measurements During Complex Motions.

    Toreyin, Hakan; Jeong, Hyeon Ki; Hersek, Sinan; Teague, Caitlin N; Inan, Omer T

    2016-09-01

    Knee-joint sounds could potentially be used to noninvasively probe the physical and/or physiological changes in the knee associated with rehabilitation following acute injury. In this paper, a system and methods for investigating the consistency of knee-joint sounds during complex motions in silent and loud background settings are presented. The wearable hardware component of the system consists of a microelectromechanical systems microphone and inertial rate sensors interfaced with a field programmable gate array-based real-time processor to capture knee-joint sound and angle information during three types of motion: flexion-extension (FE), sit-to-stand (SS), and walking (W) tasks. The data were post-processed to extract high-frequency and short-duration joint sounds (clicks) with particular waveform signatures. Such clicks were extracted in the presence of three different sources of interference: background, stepping, and rubbing noise. A histogram-vector Vn(→) was generated from the clicks in a motion-cycle n, where the bin range was 10°. The Euclidean distance between a vector and the arithmetic mean Vav(→) of all vectors in a recording normalized by the Vav(→) is used as a consistency metric dn. Measurements from eight healthy subjects performing FE, SS, and W show that the mean (of mean) consistency metric for all subjects during SS (μ [ μ (dn)] = 0.72 in silent, 0.85 in loud) is smaller compared with the FE (μ [ μ (dn)] = 1.02 in silent, 0.95 in loud) and W ( μ [ μ (dn)] = 0.94 in silent, 0.97 in loud) exercises, thereby implying more consistent click-generation during SS compared with the FE and W. Knee-joint sounds from one subject performing FE during five consecutive work-days (μ [ μ (dn) = 0.72) and five different times of a day (μ [ μ (dn) = 0.73) suggests high consistency of the clicks on different days and throughout a day. This work represents the first time, to the best of our knowledge, that joint sound consistency has been

  19. Patient Self-Assessed Passive Range of Motion of the Knee Cannot Replace Health Professional Measurements.

    Borgbjerg, Jens; Madsen, Frank; Odgaard, Anders

    2017-03-01

    The purpose of this study was to investigate whether patients can accurately self-assess their knee passive range of motion (PROM). A picture-based questionnaire for patient self-assessment of knee PROM was developed and posted to patients. The self-assessed PROM from 58 patients was compared with surgeon-assessed PROM using a short-arm goniometer. Agreement between the measurement methods was calculated with the Bland-Altman method. We calculated the sensitivity and specificity of patient-assessed PROM in dichotomously detecting knee motion impairment in both flexion (≤ 100 degrees) and extension (≥ 10-degree flexion contracture). Surgeon- and patient-assessed knee PROM showed a mean difference (95% limits of agreement) of -2.1 degrees (-42.5 to 38.3 degrees) for flexion and -8.1 degrees (-28.8 to 12.7 degrees) for extension. The sensitivity of patient self-assessed PROM in identifying knee flexion and extension impairments was 86 and 100%, respectively, whereas its specificity was 84 and 43%, respectively. Although wide limits of agreement were observed between surgeon- and patient-assessed knee PROM, the picture-based questionnaire for patient assessment of knee ROM was found to be a valid tool for dichotomously detecting knee motion impairment in flexion (≤ 100 degrees). However, the specificity of the questionnaire for detection of knee extension impairments (≥ 10-degree flexion contracture) was low, which limits is practical utility for this purpose.

  20. Auricular Acupressure for Managing Postoperative Pain and Knee Motion in Patients with Total Knee Replacement: A Randomized Sham Control Study

    Ling-hua Chang

    2012-01-01

    Full Text Available Background. Postoperative pain management remains a significant challenge for all healthcare providers. A randomized controlled trial was conducted to examine the adjuvant effects of auricular acupressure on relieving postoperative pain and improving the passive range of motion in patients with total knee replacement (TKR. Method. Sixty-two patients who had undergone a TKR were randomly assigned to the acupressure group and the sham control group. The intervention was delivered three times a day for 3 days. A visual analog scale (VAS and the Short-Form McGill Pain Questionnaire were used to assess pain intensity. Pain medication consumption was recorded, and the knee motion was measured using a goniometer. Results. The patients experienced a moderately severe level of pain postoperatively (VAS 58.66 ± 20.35 while being on the routine PCA. No differences were found in pain scores between the groups at all points. However, analgesic drug usage in the acupressure group patients was significantly lower than in the sham control group (<0.05, controlling for BMI, age, and pain score. On the 3rd day after surgery, the passive knee motion in the acupressure group patients was significantly better than in the sham control group patients (<0.05, controlling for BMI. Conclusion. The application of auricular acupressure at specific therapeutic points significantly reduces the opioid analgesia requirement and improves the knee motion in patients with TKR.

  1. Instantaneous screws of weight-bearing knee: what can the screws tell us about the knee motion.

    Wolf, Alon

    2014-07-01

    There are several ways to represent a given object's motion in a 3D space having 6DOF i.e., three translations and three rotations. Some of the methods that are used are mathematical and do not provide any geometrical insight into the nature of the motion. Screw theory is a mathematical, while at the same time, geometrical method in which the 6DOF motion of an object can be represented. We describe the 6DOF motion of a weight-bearing knee by its screw parameters, that are extracted from 3D Optical Reflective motion capture data. The screw parameters which describe the transformation of the shank with respect to the thigh in each two successive frames, is represented as the instantaneous screw axis of the motion given in its Plücker line coordinate, along with its corresponding pitch and intensity values. Moreover, the Striction curve associated with the motion provides geometrical insight into the nature of the motion and its repeatability. We describe the theoretical background and demonstrate what the screw can tell us about the motion of healthy subjects' knee.

  2. RAPID KNEE-EXTENSIONS TO INCREASE QUADRICEPS MUSCLE ACTIVITY IN PATIENTS WITH TOTAL KNEE ARTHROPLASTY

    Husted, Rasmus Skov; Wilquin, Lousia; Jakobsen, Thomas Linding

    2017-01-01

    rapid knee-extensions were associated with greater voluntary quadriceps muscle activity during an experimental strength training session, compared to that elicited using slow knee-extensions. STUDY DESIGN: A randomized cross-over study. METHODS: Twenty-four patients (age 66.5) 4-8 weeks post total knee...

  3. Reliability of knee joint range of motion and circumference measurements after total knee arthroplasty: does tester experience matter?

    Jakobsen, Thomas Linding; Christensen, Malene; Christensen, Stine Sommer;

    2010-01-01

    obtained using a universal goniometer and a tape measure, respectively. To establish reliability, intraclass correlation coefficients (ICC(2,1)) and smallest real difference (SRD) were calculated. RESULTS: The knee joint ROM and circumference measurements were generally reliable (ICC > 0.8) within......-tester in patients with total knee arthroplasty (TKA). The purpose of this study was to determine the intra-tester and inter-tester reliability of active and passive knee joint ROM and circumference in patients with TKA when administered by physiotherapists (testers) with different clinical experience. METHOD......: The design was an intra-tester, inter-tester and intra-day reliability study. Nineteen outpatients (10 females) having received a TKA were examined by an inexperienced and an experienced physiotherapist. Following a standardized protocol, active and passive knee joint ROM and circumference measurements were...

  4. Reflex responses to combined hip and knee motion in human chronic spinal cord injury

    Ming Wu, PhD

    2010-04-01

    Full Text Available The relative contributions of hip and knee proprioceptors to the origination of extensor spasms were examined in 11 subjects with chronic spinal cord injury (SCI. Ramp and hold extension and combined hip and knee oscillation movements were imposed to the right leg while the ankle was held in a static position by a custom-designed robot. Isometric joint torques of the hip, knee, and ankle and surface electromyograms (EMGs from seven leg muscles were recorded following controlled hip and knee extension. A stereotypical torque response consisting of hip flexion, knee extension, and ankle plantar flexion was observed following hip and knee perturbations. Further, the hip or knee joint posture modulated the spastic reflexes triggered by the extension movement of the other joint, with larger responses observed with the hip and knee extended. In addition, combined hip and knee oscillation movements were imposed to one leg with four different phasing conditions. The phasing between the hip and knee modulated the reflex activity triggered by hip and knee oscillations. The EMG patterns of the spastic reflexes were generally consistent with muscle timing during locomotion in human SCI. This knowledge may help identify rehabilitation strategies that produce functional movements in human SCI.

  5. Motion analysis of knee joint using dynamic volume images

    Haneishi, Hideaki; Kohno, Takahiro; Suzuki, Masahiko; Moriya, Hideshige; Mori, Sin-ichiro; Endo, Masahiro

    2006-03-01

    Acquisition and analysis of three-dimensional movement of knee joint is desired in orthopedic surgery. We have developed two methods to obtain dynamic volume images of knee joint. One is a 2D/3D registration method combining a bi-plane dynamic X-ray fluoroscopy and a static three-dimensional CT, the other is a method using so-called 4D-CT that uses a cone-beam and a wide 2D detector. In this paper, we present two analyses of knee joint movement obtained by these methods: (1) transition of the nearest points between femur and tibia (2) principal component analysis (PCA) of six parameters representing the three dimensional movement of knee. As a preprocessing for the analysis, at first the femur and tibia regions are extracted from volume data at each time frame and then the registration of the tibia between different frames by an affine transformation consisting of rotation and translation are performed. The same transformation is applied femur as well. Using those image data, the movement of femur relative to tibia can be analyzed. Six movement parameters of femur consisting of three translation parameters and three rotation parameters are obtained from those images. In the analysis (1), axis of each bone is first found and then the flexion angle of the knee joint is calculated. For each flexion angle, the minimum distance between femur and tibia and the location giving the minimum distance are found in both lateral condyle and medial condyle. As a result, it was observed that the movement of lateral condyle is larger than medial condyle. In the analysis (2), it was found that the movement of the knee can be represented by the first three principal components with precision of 99.58% and those three components seem to strongly relate to three major movements of femur in the knee bend known in orthopedic surgery.

  6. Effectiveness of prolonged use of continuous passive motion (CPM as an adjunct to physiotherapy following total knee arthroplasty: Design of a randomised controlled trial [ISRCTN85759656

    Geesink Ruud JT

    2006-02-01

    Full Text Available Abstract Background Adequate and intensive rehabilitation is an important requirement for successful Total Knee Arthroplasty. The primary focus of early rehabilitation is ambulation of patients and regaining range of motion in the knee. Although research suggests that Continuous Passive Motion should be implemented in the first rehabilitation phase following surgery, there is substantial debate about the duration of each session and the total period of CPM application and. A Cochrane review on this topic concluded that short-term use of CPM leads to greater short-term range of motion. It also suggested, however, that future research should concentrate on the treatment period during which CPM should be administered. Methods In a randomised controlled trial we intend to investigate the efficacy of prolonged use of a continuous passive motion (CPM device in the home situation as an adjunct to standardised physical therapy. The experimental treatment is compared to standardised physical therapy, in patients with osteoarthritis of the knee undergoing Total Knee Arthroplasty (TKA. Efficacy will be assessed in terms of faster improvements in range of motion and functional recovery. Seventy patients with knee osteoarthritis undergoing TKA and experiencing early postoperative flexion impairment (less than 80° of knee flexion at the time of discharge will be randomised over two treatment groups, a usual care group and an experimental group The experimental group will receive CPM + physiotherapy for 17 consecutive days after surgery, whereas the usual care group will receive the same treatment during the in-hospital phase (i.e. about four days, followed by physical therapy alone (usual care in the first two weeks after hospital discharge. From 18 days to three months after discharge, both groups will receive standardised PT. The primary focus of rehabilitation will be functional recovery (e.g. ambulation and regaining range of motion (ROM in the knee

  7. Patients' reasons for electing to undergo total knee arthroplasty impact post-operative pain severity and range of motion.

    Cremeans-Smith, Julie K; Boarts, Jessica M; Greene, Kenneth; Delahanty, Douglas L

    2009-06-01

    The present study examines the reasons cited by 103 patients for their electing to undergo total knee arthroplastic surgery and the relationship between these reasons and their post-operative pain and range of motion. Results suggest that individuals who describe different reasons for undergoing surgery vary in their post-operative recovery. Specifically, patients who cite pain as the reason they are undergoing surgery report greater levels of pain during the early post-operative period. In contrast, patients who describe goals of regaining mobility or a specific activity as their reason for undergoing surgery achieve a greater range of motion during early post-operative physical therapy. Individuals who express avoidance goals for undergoing total knee arthroplasty report more severe post-operative pain at 1 and 3 months following surgery compared to patients who express approach goals. Interventions targeted towards patients reporting pre-operative pain or avoidance goals may decrease subsequent post-operative pain and increase mobility.

  8. Motion analysis of Chinese normal knees during gait based on a novel portable system.

    Zhang, Yu; Yao, Zilong; Wang, Shaobai; Huang, Wenhan; Ma, Limin; Huang, Huayang; Xia, Hong

    2015-03-01

    Normative tibiofemoral data of Chinese or Asian subjects during gait is rarely reported. This study is aimed at investigating the six-degree-of-freedom (6DOF) knee kinematics of adult Chinese during gait, based on a novel portable system. Twenty-eight healthy Chinese subjects (56 knees) were studied during their treadmill gaits. A set of optical marker clusters were attached to the thighs and shanks of each subject, who was tracked by an optical joint kinematics measurement system. Knee landmarks were initially digitized with respect to the marker cluster sets to determine the local coordinate systems for calculation of 6DOF knee joint kinematics. The range of motion (ROM) in 6DOF and 5 kinematic parameters were calculated and compared between bilateral knees and genders. We discovered that knee rotations, as well as motion in proximodistal and mediolateral translations, showed similar patterns in flexion and extension. However, the anteroposterior translations did not show a clear pattern. The results of ROM in 6DOF obtained in this study are comparable with those reported in existing literature. No statistical difference was found between left and right knees either in the ROMs or in the 5 kinematic parameters. However, the ROM in the mediolateral direction during gait was found to be higher in men than women (P=0.014). In addition, the femurs of female subjects rotated more internally than the femurs of male during the stance phase (P=0.011). We concluded that normal Chinese knees exhibited distinct gait patterns, except for anteroposterior motion. Women and men exhibit different axial rotations and mediolateral translation patterns during their treadmill gait.

  9. Knee rotationplasty: motion of the body centre of mass during walking

    Rota, Viviana; Okita, Yusuke; Manfrini, Marco; Tesio, Luigi

    2016-01-01

    Knee rotationplasty (KRP) is a type of surgery in which the rotated ankle serves as a new knee after being removed for bone tumor. Although this limb salvage surgery is rarely indicated in properly selected patients, it may offer functional advantages over transfemoral amputation, and more durable results compared with a prosthesis. The walking mechanics of adult patients after KRP is believed to be close to that of below-knee amputees. In this study, we evaluated steady-state walking of KRP patients from the viewpoint of the overall muscle power needed to keep the body centre of mass in motion. Three adult patients after KRP, all athletes, were evaluated. Ground reactions during walking were recorded during six subsequent strides on a force treadmill. The positive mechanical work and power sustaining the motion of the centre of mass and the recovery of muscle energy due to the pendulum-like mechanism of walking were computed and compared with those obtained in previous studies from above-knee, below-knee amputees and healthy individuals. In KRP patients, walking was sustained by a muscle power output which was 1.4–3.6 times lower during the step performed on the rotated limb than on the subsequent step. The recovery of muscle energy was slightly lower (0.9) or higher (1.3–1.4 times) on the affected side. In two out of the three KRP patients, our findings were more similar to those from above-knee amputees than to those from below-knee amputees. After KRP, the rotated limb does not necessarily provide the same power provided by below-knee amputation. This may have a relevance for the paralympic classification of KRP athletes. PMID:27685013

  10. Range of joint motion and disability in patients with osteoarthritis of the knee or hip.

    Steultjens, M.P.M.; Dekker, J.; Baar, M.E. van; Oostendorp, R.A.B.; Bijlsma, J.W.J.

    2000-01-01

    OBJECTIVE: To establish the relationships between the range of joint motion (ROM) and disability in patients with osteoarthritis (OA) of the knee or hip. Two related issues were addressed: (1) the inter-relationships between ROMs of joint actions, and (2) the relationship between ROM and disability.

  11. THE ROLE OF KNEE POSITIONING AND RANGE-OF-MOTION ON THE CLOSED-STANCE FOREHAND TENNIS SWING

    Steven M. Nesbit

    2008-03-01

    Full Text Available This paper discusses the role of knee positioning and range-of- motion on the closed-stance forehand tennis swing. The analyses of tennis swing mechanics were performed using a computer model comprised of a full-body model of a human and an inertial model of a racket. The model was driven by subject forehand swings (16 female college-level subjects recorded with a high-speed digital motion analysis system. The study discovered that both initial knee positioning and range-of-motion were positively related to racket velocity and characteristic of more skilled players. The direct effects of knee positioning and range-of-motion on racket movement are minimal, however there are several indirect biomechanical effects on the forehand motion such as movement of the body mass center, work of the knee, hip and back joints, and the angular range-of-motion of the hips and torso. Some of these indirect effects were related to racket velocity and characteristic of more skilled players. Factors that influenced knee positioning and range-of-motion include years of playing, amount of coaching, and body style. Efforts to both increase and restrict the knee movements of the subjects resulted in substantially lower racket velocities (and other detrimental biomechanical effects implying that there may be optimal knee positions and range-of-motion for a given subject. The most skilled subject exhibited a high degree of consistency of knee positioning and range-of-motion. This subject adjusted for varying ball height through modified initial knee positioning while maintaining fairly constant ranges-of-motion

  12. Safety of Early Application of Continuous Passive Motion in Patients after Total Knee Arthroplasty

    顾晓园; 陈文红; 张中南; 励建安

    2002-01-01

    ObjectiveThis research aimed to study the effect of early application of continuous passive motion (CPM) on the drainage volume of knee joints post total knee arthroplasty (TKA).MethodsThe drainage volume was measured 1 h before,during and after CPM on the day and next day of the operation.ResultsThere was no significant difference in the drainage volume before,during and after CPM(P >0.05).ConclusionEarly application of CPM is safe for TKA patients.``

  13. Safety of Early Application of Continuous Passive Motion in Patients after Total Knee Arthroplasty

    顾晓园; 陈文红; 等

    2002-01-01

    Objective This research aimed to study the effect of early application of continuous passive motion(CPM) on the drainage volume of knee joints post total knee arthroplasty (TKA).Methods The drainage volume was measured 1h before,during and after CPM on the day and next day of the operation.Results There was no significant difference in the drainage volume before,during and after CPM(P>0.05).Conclusion Early application of CPM is safe for TKA patients.

  14. A parallel framework for the FE-based simulation of knee joint motion.

    Wawro, Martin; Fathi-Torbaghan, Madjid

    2004-08-01

    We present an object-oriented framework for the finite-element (FE)-based simulation of the human knee joint motion. The FE model of the knee joint is acquired from the patients in vivo by using magnetic resonance imaging. The MRI images are converted into a three-dimensional model and finally an all-hexahedral mesh for the FE analysis is generated. The simulation environment uses nonlinear finite-element analysis (FEA) and is capable of handling contact of the model to handle the complex rolling/sliding motion of the knee joint. The software strictly follows object-oriented concepts of software engineering in order to guarantee maximum extensibility and maintainability. The final goal of this work-in-progress is the creation of a computer-based biomechanical model of the knee joint which can be used in a variety of applications, ranging from prosthesis design and treatment planning (e.g., optimal reconstruction of ruptured ligaments) over surgical simulation to impact computations in crashworthiness simulations.

  15. Knee joint secondary motion accuracy improved by quaternion-based optimizer with bony landmark constraints.

    Wang, Hongsheng; Zheng, Naiqaun Nigel

    2010-12-01

    Skin marker-based motion analysis has been widely used in biomechanical studies and clinical applications. Unfortunately, the accuracy of knee joint secondary motions is largely limited by the nonrigidity nature of human body segments. Numerous studies have investigated the characteristics of soft tissue movement. Utilizing these characteristics, we may improve the accuracy of knee joint motion measurement. An optimizer was developed by incorporating the soft tissue movement patterns at special bony landmarks into constraint functions. Bony landmark constraints were assigned to the skin markers at femur epicondyles, tibial plateau edges, and tibial tuberosity in a motion analysis algorithm by limiting their allowed position space relative to the underlying bone. The rotation matrix was represented by quaternion, and the constrained optimization problem was solved by Fletcher's version of the Levenberg-Marquardt optimization technique. The algorithm was validated by using motion data from both skin-based markers and bone-mounted markers attached to fresh cadavers. By comparing the results with the ground truth bone motion generated from the bone-mounted markers, the new algorithm had a significantly higher accuracy (root-mean-square (RMS) error: 0.7 ± 0.1 deg in axial rotation and 0.4 ± 0.1 deg in varus-valgus) in estimating the knee joint secondary rotations than algorithms without bony landmark constraints (RMS error: 1.7 ± 0.4 deg in axial rotation and 0.7 ± 0.1 deg in varus-valgus). Also, it predicts a more accurate medial-lateral translation (RMS error: 0.4 ± 0.1 mm) than the conventional techniques (RMS error: 1.2 ± 0.2 mm). The new algorithm, using bony landmark constrains, estimates more accurate secondary rotations and medial-lateral translation of the underlying bone.

  16. Comparison of Range of Motion After Total Knee Prosthesis According to Different Type of Prosthesis

    Firat Seyfettinoglu

    2016-07-01

    Full Text Available Aim: The aim of this study is to determine the effectiveness and range of motion of different type of knee prosthesis. Material and Method: This study includes 180 of 225 patients (139 F, 41 M, average age: 65, range of age: 51-82 between April 2005 and September 2007 with the diagnosis of gonarthrosis. All patients underwent to primary total knee arthroplasty. Primary osteoartrhritis is the reason of gonarthrosis. The patients with secondary osteoartrhritis were excluded from the study. All the patients were operated by the same surgical team and rehabilitated after surgery. Patella didnt change any patient. PCL was protected in some of the patients and cut some of patients. Totally seven type prosthesis in 16 subgroup were applied to the patients. All measurement were done by the same surgeon. Average follow up period was 31 months (24-49 months. Results: Patients without subgrouping were tested according to the range of motion before and after surgery to the type of the prosthesis trademark. Range of motion was decreased with the usage of Rotaglide and LCS® type of prosthesis. Range of motion didnt change with the usage of Maxim and Kinemax type. The range of motion increased in the other trademark of prosthesis. Flexion angle was increased statistically significant with nexgen® and scorpio® prosthesis (p

  17. Comparing Levels of Depression in Healthy Active and Inactive Elders versus Those with Knee Osteoarthritis Disease

    Amir Shams

    2016-04-01

    Full Text Available Knee osteoarthritis can have negative effects on the physical and mental conditions, social and family relations, general health and positive feelings of elders. For example, severe limitation of motion and increased depression, which are results of this disease, can have negative impacts on elders. The purpose of this study was to compare the levels of depression in healthy active and inactive elders versus those with knee osteoarthritis disease. Two hundred and twenty (220 elders with knee osteoarthritis disease (110 active and 110 inactive patients and 220 healthy elders (110 active and 110 inactive were voluntarily selected, and they filled the questionnaire about elders’ personal characteristics, physical activity and depression levels. Four groups had differences with respect to education, age and gender. The results of chi-square test revealed that women with knee osteoarthritis disease had increased levels of depression compared to men with the same condition (p<0.05. Older patients had increased levels of depression and educated elders reported lower levels of depression. The results of the one way analysis of variance (ANOVA revealed that there exist a significant difference in depression scores of healthy active and healthy inactive elders and those with knee osteoarthritis disease. The results of Tukey’s test revealed that healthy active elder had lower depression scores compared to inactive elders with knee osteoarthritis disease. Carrying out exercises and physical activities can help improve the health state of patients with knee osteoarthritis problem and can also improve the elders’ mental condition and thus decrease their pain and depression.

  18. Designing for scale: development of the ReMotion Knee for global emerging markets.

    Hamner, Samuel R; Narayan, Vinesh G; Donaldson, Krista M

    2013-09-01

    Amputees living in developing countries have a profound need for affordable and reliable lower limb prosthetic devices. The World Health Organization estimates there are approximately 30 million amputees living in low-income countries, with up to 95% lacking access to prosthetic devices. Effective prosthetics can significantly affect the lives of these amputees by increasing opportunity for employment and providing improvements to long-term health and well-being. However, current solutions are inadequate: state-of-the-art solutions from the US and Europe are cost-prohibitive, while low-cost devices have been challenged by poor quality and/or unreliable performance, and have yet to achieve large scale impact. The introduction of new devices is hampered by the lack of a cohesive prosthetics industry in low-income areas; the current network of low-cost prosthetic clinics is informal and loosely organized with significant disparities in geography, patient volume and demographics, device procurement, clinical and logistical infrastructure, and funding. At D-Rev (Design Revolution) we are creating the ReMotion Knee, which is an affordable polycentric prosthetic knee joint that performs on par with devices in more industrialized regions, like the US and Europe. As of September 2012, over 4200 amputees have been fitted with the initial version of the ReMotion Knee through a partnership with the JaipurFoot Organization, with an 79% compliance rate after 2 years. We are currently scaling production of the ReMotion Knee using centralized manufacturing and distribution to serve the existing clinics in low-income countries and increase the availability of devices for amputees without access to appropriate care. At D-Rev, we develop products that target these customers through economically-sustainable models and provide a measurable impact in the lives of the world's amputees.

  19. Displacement of the medial meniscus within the passive motion characteristics of the human knee joint: an RSA study in human cadaver knees.

    Tienen, T G; Buma, P; Scholten, J G F; van Kampen, A; Veth, R P H; Verdonschot, N

    2005-05-01

    The objective of this study was to validate an in vitro human cadaver knee-joint model for the evaluation of the meniscal movement during knee-joint flexion. The question was whether our model showed comparable meniscal displacements to those found in earlier meniscal movement studies in vivo. Furthermore, we determined the influence of tibial torque on the meniscal displacement during knee-joint flexion. Three tantalum beads were inserted in the medial meniscus of six human-cadaver joints. The knee joints were placed and loaded in a loading apparatus, and the movements of the beads were determined by means of RSA during knee-joint flexion and extension with and without internal tibial (IT) and external tibial (ET) torque. During flexion without tibial torque, all menisci moved in posterior and lateral direction. The anterior horn showed significantly greater excursions than the posterior horn in both posterior and lateral direction. Internal tibial torque caused an anterior displacement of the pathway on the tibial plateau. External tibial torque caused a posterior displacement of the pathway. External tibial torque restricted the meniscal displacement during the first 30 degrees of knee-joint flexion. The displacements of the meniscus in this experiment were similar to the displacements described in the in vivo MRI studies. Furthermore, the application of tibial torque confirmed the relative immobility of the posterior horn of the meniscus. During external tibial torque, the posterior displacement of the pathway on the tibial plateau during the first 30 degrees of flexion might be restricted by the attached knee-joint capsule or the femoral condyle. This model revealed representative meniscal displacements during simple knee-joint flexion and also during the outer limits of passive knee-joint motion.

  20. Effectiveness of prolonged use of continuous passive motion (CPM, as an adjunct to physiotherapy, after total knee arthroplasty

    Geesink Ruud JT

    2008-04-01

    Full Text Available Abstract Background Adequate and intensive rehabilitation is an important requirement for successful total knee arthroplasty. Although research suggests that Continuous Passive Motion (CPM should be implemented in the first rehabilitation phase after surgery, there is substantial debate about the duration of each session and the total period of CPM application. A Cochrane review on this topic concluded that short-term use of CPM leads to greater short-term range of motion. It also suggested, however, that future research should concentrate on the treatment period during which CPM should be administered. Methods In a randomised controlled trial we investigated the effectiveness of prolonged CPM use in the home situation as an adjunct to standardised PT. Efficacy was assessed in terms of faster improvements in range of motion (RoM and functional recovery, measured at the end of the active treatment period, 17 days after surgery. Sixty patients with knee osteoarthritis undergoing TKA and experiencing early postoperative flexion impairment were randomised over two treatment groups. The experimental group received CPM + PT for 17 consecutive days after surgery, whereas the usual care group received the same treatment during the in-hospital phase (i.e. about four days, followed by PT alone (usual care in the first two weeks after hospital discharge. From 18 days to three months after surgery, both groups received standardised PT. The primary focus of rehabilitation was functional recovery (e.g. ambulation and regaining RoM in the knee. Results Prolonged use of CPM slightly improved short-term RoM in patients with limited RoM at the time of discharge after total knee arthroplasty when added to a semi-standard PT programme. Assessment at 6 weeks and three months after surgery found no long-term effects of this intervention Neither did we detect functional benefits of the improved RoM at any of the outcome assessments. Conclusion Although results

  1. Evaluation Of Patellar Tracking During Knee Range Of Motion In Patients With Patellar Lateralization And Normal Subjects

    Goharpei S

    2004-08-01

    Full Text Available Background: Patellofemoral joint disorders are the most common cause of anterior knee pain in patients who referred to orthopedic clinics. Patellar lateralization cause anterior knee pain due to weakness of vastus medialis oblique muscle or tightness of lateral structures like lateral retinaculum or iliotibial band muscle. Materials and Methods: For evaluation of this abnormality, plane radiography, CT scan and MRI are useful. In plane radiography only one view in a single joint position can be obtained, because of that it is not a good method to detect abnormal tracking during knee range of motion. The purpose of this study was to evaluate patellar tracking by kinematics MRI during five serial degrees of knee range of motion (40, 30, 20, 10, 0 degrees in 30 patients with patellar lateralization and 10 normal subjects, aged 18-30 years. Results and Conclusion: tistical analysis showed that in patients group, patella had the most stability in 40 degree of knee flexion and this stability reduced when knee reached to full extension. At this point, patella moved laterally and the most instability was seen during 20 to 0 degree of knee extension.

  2. Correlation between hip function and knee kinematics evaluated by three-dimensional motion analysis during lateral and medial side-hopping

    Itoh, Hiromitsu; Takiguchi, Kohei; Shibata, Yohei; Okubo, Satoshi; Yoshiya, Shinichi; Kuroda, Ryosuke

    2016-01-01

    [Purpose] Kinematic and kinetic characteristics of the limb during side-hopping and hip/knee interaction during this motion have not been clarified. The purposes of this study were to examine the biomechanical parameters of the knee during side hop and analyze its relationship with clinical measurements of hip function. [Subjects and Methods] Eleven male college rugby players were included. A three-dimensional motion analysis system was used to assess motion characteristics of the knee during side hop. In addition, hip range of motion and muscle strength were evaluated. Subsequently, the relationship between knee motion and the clinical parameters of the hip was analyzed. [Results] In the lateral touchdown phase, the knee was positioned in an abducted and externally rotated position, and increasing abduction moment was applied to the knee. An analysis of the interaction between knee motion and hip function showed that range of motion for hip internal rotation was significantly correlated with external rotation angle and external rotation/abduction moments of the knee during the lateral touchdown phase. [Conclusion] Range of motion for hip internal rotation should be taken into consideration for identifying the biomechanical characteristics in the side hop test results.

  3. Prevalence of knee instability in relation to sports activity

    Hahn, Thomas; Foldspang, Anders; Hansen, Thorsten Ingemann

    2001-01-01

    to be positively associated with female gender and different features of occupational work. In conclusion, knee instability is a commonly reported phenomenon among active athletes. It was found to be independent of the type and the amount of sports activity but highly dependent on female gender, type and amount...

  4. Validity and reliability of using photography for measuring knee range of motion: a methodological study

    Adie Sam

    2011-04-01

    Full Text Available Abstract Background The clinimetric properties of knee goniometry are essential to appreciate in light of its extensive use in the orthopaedic and rehabilitative communities. Intra-observer reliability is thought to be satisfactory, but the validity and inter-rater reliability of knee goniometry often demonstrate unacceptable levels of variation. This study tests the validity and reliability of measuring knee range of motion using goniometry and photographic records. Methods Design: Methodology study assessing the validity and reliability of one method ('Marker Method' which uses a skin marker over the greater trochanter and another method ('Line of Femur Method' which requires estimation of the line of femur. Setting: Radiology and orthopaedic departments of two teaching hospitals. Participants: 31 volunteers (13 arthritic and 18 healthy subjects. Knee range of motion was measured radiographically and photographically using a goniometer. Three assessors were assessed for reliability and validity. Main outcomes: Agreement between methods and within raters was assessed using concordance correlation coefficient (CCCs. Agreement between raters was assessed using intra-class correlation coefficients (ICCs. 95% limits of agreement for the mean difference for all paired comparisons were computed. Results Validity (referenced to radiographs: Each method for all 3 raters yielded very high CCCs for flexion (0.975 to 0.988, and moderate to substantial CCCs for extension angles (0.478 to 0.678. The mean differences and 95% limits of agreement were narrower for flexion than they were for extension. Intra-rater reliability: For flexion and extension, very high CCCs were attained for all 3 raters for both methods with slightly greater CCCs seen for flexion (CCCs varied from 0.981 to 0.998. Inter-rater reliability: For both methods, very high ICCs (min to max: 0.891 to 0.995 were obtained for flexion and extension. Slightly higher coefficients were obtained

  5. Dynamic splinting for knee flexion contracture following total knee arthroplasty: a case report.

    Finger, Eric; Willis, F Buck

    2008-01-01

    Total Knee Arthroplasty operations are increasing in frequency, and knee flexion contracture is a common pathology, both pre-existing and post-operative. A 61-year-old male presented with knee flexion contracture following a total knee arthroplasty. Physical therapy alone did not fully reduce the contracture and dynamic splinting was then prescribed for daily low-load, prolonged-duration stretch. After 28 physical therapy sessions, the active range of motion improved from -20 degrees to -12 degrees (stiff knee still lacking full extension), and after eight additional weeks with nightly wear of dynamic splint, the patient regained full knee extension, (active extension improved from -12 degrees to 0 degrees ).

  6. Accuracy of a custom physical activity and knee angle measurement sensor system for patients with neuromuscular disorders and gait abnormalities.

    Feldhege, Frank; Mau-Moeller, Anett; Lindner, Tobias; Hein, Albert; Markschies, Andreas; Zettl, Uwe Klaus; Bader, Rainer

    2015-05-06

    Long-term assessment of ambulatory behavior and joint motion are valuable tools for the evaluation of therapy effectiveness in patients with neuromuscular disorders and gait abnormalities. Even though there are several tools available to quantify ambulatory behavior in a home environment, reliable measurement of joint motion is still limited to laboratory tests. The aim of this study was to develop and evaluate a novel inertial sensor system for ambulatory behavior and joint motion measurement in the everyday environment. An algorithm for behavior classification, step detection, and knee angle calculation was developed. The validation protocol consisted of simulated daily activities in a laboratory environment. The tests were performed with ten healthy subjects and eleven patients with multiple sclerosis. Activity classification showed comparable performance to commercially available activPAL sensors. Step detection with our sensor system was more accurate. The calculated flexion-extension angle of the knee joint showed a root mean square error of less than 5° compared with results obtained using an electro-mechanical goniometer. This new system combines ambulatory behavior assessment and knee angle measurement for long-term measurement periods in a home environment. The wearable sensor system demonstrated high validity for behavior classification and knee joint angle measurement in a laboratory setting.

  7. Accuracy of a Custom Physical Activity and Knee Angle Measurement Sensor System for Patients with Neuromuscular Disorders and Gait Abnormalities

    Frank Feldhege

    2015-05-01

    Full Text Available Long-term assessment of ambulatory behavior and joint motion are valuable tools for the evaluation of therapy effectiveness in patients with neuromuscular disorders and gait abnormalities. Even though there are several tools available to quantify ambulatory behavior in a home environment, reliable measurement of joint motion is still limited to laboratory tests. The aim of this study was to develop and evaluate a novel inertial sensor system for ambulatory behavior and joint motion measurement in the everyday environment. An algorithm for behavior classification, step detection, and knee angle calculation was developed. The validation protocol consisted of simulated daily activities in a laboratory environment. The tests were performed with ten healthy subjects and eleven patients with multiple sclerosis. Activity classification showed comparable performance to commercially available activPAL sensors. Step detection with our sensor system was more accurate. The calculated flexion-extension angle of the knee joint showed a root mean square error of less than 5° compared with results obtained using an electro-mechanical goniometer. This new system combines ambulatory behavior assessment and knee angle measurement for long-term measurement periods in a home environment. The wearable sensor system demonstrated high validity for behavior classification and knee joint angle measurement in a laboratory setting.

  8. Approach to the active patient with chronic anterior knee pain.

    Atanda, Alfred; Ruiz, Devin; Dodson, Christopher C; Frederick, Robert W

    2012-02-01

    The diagnosis and management of chronic anterior knee pain in the active individual can be frustrating for both the patient and physician. Pain may be a result of a single traumatic event or, more commonly, repetitive overuse. "Anterior knee pain," "patellofemoral pain syndrome," and "chondromalacia" are terms that are often used interchangeably to describe multiple conditions that occur in the same anatomic region but that can have significantly different etiologies. Potential pain sources include connective or soft tissue irritation, intra-articular cartilage damage, mechanical irritation, nerve-mediated abnormalities, systemic conditions, or psychosocial issues. Patients with anterior knee pain often report pain during weightbearing activities that involve significant knee flexion, such as squatting, running, jumping, and walking up stairs. A detailed history and thorough physical examination can improve the differential diagnosis. Plain radiographs (anteroposterior, anteroposterior flexion, lateral, and axial views) can be ordered in severe or recalcitrant cases. Treatment is typically nonoperative and includes activity modification, nonsteroidal anti-inflammatory drugs, supervised physical therapy, orthotics, and footwear adjustment. Patients should be informed that it may take several months for symptoms to resolve. It is important for patients to be aware of and avoid aggravating activities that can cause symptom recurrence. Patients who are unresponsive to conservative treatment, or those who have an underlying systemic condition, should be referred to an orthopedic surgeon or an appropriate medical specialist.

  9. The efficacy of brotzman physiotherapy protocol on pain and knee range of motion in post surgical total knee arthroplasty subjects with obesity

    K Narasimha sridhar

    2013-04-01

    Full Text Available Background:To evaluate the efficacy of Brotzman physiotherapy protocol on pain and knee range of motion in post surgical T.K.A subjects with obesity and normal BMI . Materials and Methods:30 subjects were divided into two groups based on BMI. The group I having normal BMI (18.5 – 24.9 and group II having BMI more than 30. Both groups received Brotzman physiotherapy protocols for duration of 30 - 45 minutes, 1 se ssion per day, 6 days per week for a total of 6 weeks. Results:After 6 weeks treatment period, the subjects in thegroup I were compared with the subjects in the group II. Group I had shown a significant difference with outcome measures at 0.05 level.Conclusion:The study shows that there is a marginal significance ofBROTZMAN physiotherapy protocol in TKA subjects with obesity regarding relief of pain, improvement of knee ROM and WOMAC indx.

  10. A pneumatically powered knee-ankle-foot orthosis (KAFO with myoelectric activation and inhibition

    Ferris Daniel P

    2009-06-01

    Full Text Available Abstract Background The goal of this study was to test the mechanical performance of a prototype knee-ankle-foot orthosis (KAFO powered by artificial pneumatic muscles during human walking. We had previously built a powered ankle-foot orthosis (AFO and used it effectively in studies on human motor adaptation, locomotion energetics, and gait rehabilitation. Extending the previous AFO to a KAFO presented additional challenges related to the force-length properties of the artificial pneumatic muscles and the presence of multiple antagonistic artificial pneumatic muscle pairs. Methods Three healthy males were fitted with custom KAFOs equipped with artificial pneumatic muscles to power ankle plantar flexion/dorsiflexion and knee extension/flexion. Subjects walked over ground at 1.25 m/s under four conditions without extensive practice: 1 without wearing the orthosis, 2 wearing the orthosis with artificial muscles turned off, 3 wearing the orthosis activated under direct proportional myoelectric control, and 4 wearing the orthosis activated under proportional myoelectric control with flexor inhibition produced by leg extensor muscle activation. We collected joint kinematics, ground reaction forces, electromyography, and orthosis kinetics. Results The KAFO produced ~22%–33% of the peak knee flexor moment, ~15%–33% of the peak extensor moment, ~42%–46% of the peak plantar flexor moment, and ~83%–129% of the peak dorsiflexor moment during normal walking. With flexor inhibition produced by leg extensor muscle activation, ankle (Pearson r-value = 0.74 ± 0.04 and knee ( r = 0.95 ± 0.04 joint kinematic profiles were more similar to the without orthosis condition compared to when there was no flexor inhibition (r = 0.49 ± 0.13 for ankle, p = 0.05, and r = 0.90 ± 0.03 for knee, p = 0.17. Conclusion The proportional myoelectric control with flexor inhibition allowed for a more normal gait than direct proportional myoelectric control. The current

  11. 78 FR 38098 - Proposed Information Collection (Knee and Lower Leg Disability Benefits Questionnaire) Activity...

    2013-06-25

    ... AFFAIRS Proposed Information Collection (Knee and Lower Leg Disability Benefits Questionnaire) Activity... Disability Benefits Questionnaire)'' in any correspondence. During the comment period, comments may be viewed.... SUPPLEMENTARY INFORMATION: Title: Knee and Lower Leg Conditions Disability Benefits Questionnaire, VA Form...

  12. Can generic knee joint models improve the measurement of osteoarthritic knee kinematics during squatting activity?

    Clément, Julien; Dumas, Raphaël; Hagemeister, Nicola; de Guise, Jaques A

    2017-01-01

    Knee joint kinematics derived from multi-body optimisation (MBO) still requires evaluation. The objective of this study was to corroborate model-derived kinematics of osteoarthritic knees obtained using four generic knee joint models used in musculoskeletal modelling - spherical, hinge, degree-of-freedom coupling curves and parallel mechanism - against reference knee kinematics measured by stereo-radiography. Root mean square errors ranged from 0.7° to 23.4° for knee rotations and from 0.6 to 9.0 mm for knee displacements. Model-derived knee kinematics computed from generic knee joint models was inaccurate. Future developments and experiments should improve the reliability of osteoarthritic knee models in MBO and musculoskeletal modelling.

  13. Uncertainty of knee joint muscle activity during knee joint torque exertion: the significance of controlling adjacent joint torque.

    Nozaki, Daichi; Nakazawa, Kimitaka; Akai, Masami

    2005-09-01

    In the single-joint torque exertion task, which has been widely used to control muscle activity, only the relevant joint torque is specified. However, the neglect of the neighboring joint could make the procedure unreliable, considering our previous result that even monoarticular muscle activity level is indefinite without specifying the adjacent joint torque. Here we examined the amount of hip joint torque generated with knee joint torque and its influence on the activity of the knee joint muscles. Twelve healthy subjects were requested to exert various levels of isometric knee joint torque. The knee and hip joint torques were obtained by using a custom-made device. Because no information about hip joint torque was provided to the subjects, the hip joint torque measured here was a secondary one associated with the task. The amount of hip joint torque varied among subjects, indicating that they adopted various strategies to achieve the task. In some subjects, there was a considerable internal variability in the hip joint torque. Such variability was not negligible, because the knee joint muscle activity level with respect to the knee joint torque, as quantified by surface electromyography (EMG), changed significantly when the subjects were requested to change the strategy. This change occurred in a very systematic manner: in the case of the knee extension, as the hip flexion torque was larger, the activity of mono- and biarticular knee extensors decreased and increased, respectively. These results indicate that the conventional single knee joint torque exertion has the drawback that the intersubject and/or intertrial variability is inevitable in the relative contribution among mono- and biarticular muscles because of the uncertainty of the hip joint torque. We discuss that the viewpoint that both joint torques need to be considered will bring insights into various controversial problems such as the shape of the EMG-force relationship, neural factors that help

  14. Dynamic splinting for knee flexion contracture following total knee arthroplasty: a case report

    Finger, Eric; Willis, F Buck

    2008-01-01

    Total Knee Arthroplasty operations are increasing in frequency, and knee flexion contracture is a common pathology, both pre-existing and post-operative. A 61-year-old male presented with knee flexion contracture following a total knee arthroplasty. Physical therapy alone did not fully reduce the contracture and dynamic splinting was then prescribed for daily low-load, prolonged-duration stretch. After 28 physical therapy sessions, the active range of motion improved from -20° to -12° (stiff ...

  15. Autologous platelet gel and fibrin sealant enhance the efficacy of total knee arthroplasty : improved range of motion, decreased length of stay and a reduced incidence of arthrofibrosis

    Everts, Peter A. M.; Devilee, Roger J. J.; Oosterbos, Cornelis J. M.; Mahoney, Christine Brown; Schattenkerk, Maarten Eeftinck; Knape, Johannes T. A.; van Zundert, Andre

    2007-01-01

    In this study we describe the potential role of autologous platelet gel and fibrin sealant in unilateral total knee arthroplasty to improve the postoperative range of motion and to reduce the incidence of arthrofibrosis. Total knee arthroplasty is often associated with a considerable amount of post-

  16. Effect of repeated manipulation on range of motion in patients with stiff total knee arthroplasty.

    Choi, Ho-Rim; Siliski, John M; Malchau, Henrik; Kwon, Young-Min

    2015-03-01

    Although manipulation under anesthesia (MUA) has been considered effective first-line treatment for stiff total knee arthroplasty (TKA), there is no consensus regarding the usefulness of repeated MUA. The purpose of this study was to investigate the usefulness of repeated MUA performed for patients in whom satisfactory range of motion (ROM) was not achieved by MUA. The authors retrospectively reviewed 15 patients who underwent repeated MUA after failure of initial MUA for stiff TKA. Demographic and ROM data were collected. A final ROM of less than 90° was considered a failed manipulation (failure group) and a final ROM of 90° or more was considered a successful manipulation (success group). Average pre-repeated MUA ROM (72.3°±19.5°) immediately improved to 112.3°±9.7° (Pstiff TKA. The success rate of repeated MUA was less than that of primary MUA; however, it is a useful treatment modality for stiff TKA. Decreased pre-TKA ROM appeared to be associated with poor outcomes after repeated MUA.

  17. Biofeedback relaxation for pain associated with continuous passive motion in Taiwanese patients after total knee arthroplasty.

    Wang, Tsae-Jyy; Chang, Ching-Fen; Lou, Meei-Fang; Ao, Man-Kuan; Liu, Chiung-Chen; Liang, Shu-Yuan; Wu, Shu-Fang Vivienne; Tung, Heng-Hsing

    2015-02-01

    Effective pain management is crucial for patient recovery after total knee arthroplasty (TKA). Biofeedback therapy, which encourages relaxation and helps alleviate various conditions associated with stress, may help to decrease postoperative pain in patients undergoing TKA. A quasi- experimental design was used to investigate the efficacy of a biofeedback relaxation intervention in reducing pain associated with postoperative continuous passive motion (CPM) therapy. Sixty-six patients admitted to a general hospital in Taiwan for TKA were recruited and randomly assigned to the intervention or control group. The intervention group received biofeedback training twice daily for 5 days, concurrent with CPM therapy, whereas the control group did not receive the biofeedback intervention. Pain was measured using a numeric rating scale before and after each CPM therapy session on postoperative days 1 through 5. The CPM-elicited pain score was calculated by subtracting the pre-CPM pain score from the post-CPM pain score. Results of repeated-measures analysis of variance showed intervention group reported significantly less pain caused by CPM than did the control group (f = 29.70, p biofeedback relaxation, a non-invasive and non-pharmacological intervention, as a complementary treatment option for pain management in this population.

  18. ARTHROFIBROSIS FOLLOWING TOTAL KNEE ARTHROPLASTY

    Ravi B. Solanki

    2014-11-01

    Full Text Available Arthrofibrosis following total knee arthroplasty is an uncommon complication defined as less than 80 degrees of knee flexion 6-8 weeks post operatively. It is characterized by abnormal scarring of the joint in which the formation of dense fibrous tissue and tissue metaplasia prevent normal range of motion. Clinical features include limited knee Range of motion with extension deficit, pain with activities of daily living and unusual amount of pain and swelling post operatively in the absence of infection, bleeding or mechanical complications. We present case of 55 years old female who undergone for total knee replacement before 3 months and presented to our department with complain of knee pain and swelling with activities of daily living. She was diagnosed on the basis of clinical examination. Her detailed evaluation was carried out and Physiotherapy treatment was started.

  19. Kinematics of hip, knee, ankle of the young and elderly Chinese people during kneeling activity

    Hai ZHOU; Dong-mei WANG; Tao-ran LIU; Xiang-sen ZENG; Cheng-tao WANG

    2012-01-01

    Objective:The purpose of this study was to measure the kinematics of the lower limbs of Chinese people during normal kneeling activity,as such data could be valuable in designing joint prosthesis and arthroplasty that meet the needs of Chinese citizens' daily activities.Methods:Thirty young and twenty elderly Chinese participants with no personal history of joint diseases were recruited,and matched by age (average age:23.8 years for the young group,60.8 years for the elderly group).Each participant performed six trials during which three-dimensional (3D) kinematics data were collected and the means of the 3D angles of the ankle,knee,and hip joints of two groups were calculated.Results:There were no obvious differences between the two groups in the knee and ankle joints.The mean range of knee flexion was 139.6° for the young group and 140.9° for the elderly group.The mean range of ankle flexion was 35.7° for the young group and 37.6° for the elderly group.The maximal eccentric flexion at the hip joint was 67.5° for the young group compared to 100.5° for the elderly group.Conclusions:The elderly uses more hip flexion angles than the young when assuming the kneeling posture.The ranges of motion obtained during kneeling activity are greater than the reported mean ranges of motion achieved following joint arthroplasty.The data could be valuable in establishing criteria for lower limb prosthetics and rehabilitation protocol for the Chinese population.

  20. Influence of advanced prosthetic knee joints on perceived performance and everyday life activity level of low-functional persons with a transfemoral amputation or knee disarticulation

    Theeven, P.J.; Hemmen, B.; Geers, R.P.; Smeets, R.J.P.; Brink, P.R.; Seelen, H.A.

    2012-01-01

    OBJECTIVE: To assess the effects of two types of microprocessor-controlled prosthetic knee joints (MPKs) on perceived performance and everyday life activity level. DESIGN: Randomized cross-over trial. SUBJECTS: Thirty persons with a unilateral above-knee amputation or knee disarticulation classified

  1. Knee pain during activities of daily living and its relationship with physical activity in patients with early and severe knee osteoarthritis.

    Fukutani, Naoto; Iijima, Hirotaka; Aoyama, Tomoki; Yamamoto, Yuko; Hiraoka, Masakazu; Miyanobu, Kazuyuki; Jinnouchi, Masashi; Kaneda, Eishi; Tsuboyama, Tadao; Matsuda, Shuichi

    2016-09-01

    This study aimed to investigate whether knee pain during various activities of daily living (ADLs) is associated with physical activity in patients with early and severe knee osteoarthritis (OA). We hypothesized that the painful ADLs associated with decreased physical activity differ according to disease severity. This cross-sectional study enrolled 270 patients with medial knee OA, assigned to either the early (Kellgren Lawrence [K/L] grade 1-2) or the severe group (K/L grade 3-4). Physical activity was assessed using a pedometer. Knee pain during six ADLs (waking up in the morning, walking on a flat surface, ascending stairs, etc.) was evaluated using a questionnaire. We performed multiple regression and quantile regression analysis to investigate whether knee pain during each ADL was associated with physical activity. In the early group, the more knee pain they experienced while ascending stairs, the lower their physical activity was (75th regression coefficient = -1033.70, P = 0.018). In the severe group, the more knee pain they experienced while walking on a flat surface or bending to the floor or standing up, the lower their physical activity was (unstandardized coefficients = -1850.87, P = 0.026; unstandardized coefficients = -2640.35, P = 0.010). Knee pain while ascending stairs and while walking on a flat surface or bending to the floor or standing up was a probable limiting factor for physical activity in early and severe knee OA, respectively. These findings suggested that a reduction in task-specific knee pain according to disease severity could improve physical activity levels.

  2. Interaction between pre-landing activities and stiffness regulation of the knee joint musculoskeletal system in the drop jump: implications to performance.

    Horita, T; Komi, P V; Nicol, C; Kyröläinen, H

    2002-11-01

    The purpose of the present study was to investigate the interaction between the pre-landing activities and the stiffness regulation of the knee joint musculoskeletal system and the takeoff speed during a drop jump (DJ). Nine healthy male subjects performed a DJ test from the height of 50 cm. The surface electromyographic (EMG) activity of the vastus lateralis (VL) muscle was recorded to evaluate both the pre-landing and post-landing muscle activation levels. Simultaneous recording of the jumping motion and ground reaction force was performed by a high-speed video camera (100 frames x s(-1)), and a force platform was employed to allow joint moment analysis. Joint stiffness was calculated by a linear regression of the knee joint moment/angle relationship. Elasticity of the knee extensor muscle during DJ was estimated by means of a four-element muscle model consisting of a parallel elastic component, a series elastic component (SEC), a viscous damper, and a contractile element. DJ performance correlated positively with the positive peak power of the knee joint (P knee joint at the end of stretch (P power of the ankle joint. The knee joint moment at the end of stretch correlated with the SEC stiffness during the transmission phase from the end of the initial impact to the onset of the concentric action (P knee extensors (P analysis showed that the SEC stiffness during the transmission phase of the knee joint can be explained by a combination of the pre-activity of the VL muscle and the knee joint angular velocity at touchdown (F = 5.76, P knee extensor muscle in conjunction with the muscle contractile property play a major role in regulating the performance in DJ.

  3. Effect of Planning on Trunk Motion and Knee Moments During a Side Step Cut Task

    Houck, Jeff; Gorniak, Stacey; Nicholson, Kristen

    2004-03-01

    Recent studies suggest that alterations in knee biomechanics associated with unanticipated cutting tasks place athletes at higher risk of knee injuries. Besier et al observed alterations in knee moments during unanticipated cutting tasks that were consistent with in-vitro ACL injury mechanisms. During similar tasks, Patla et al observed lateral trunk lean and decreased foot placement, suggesting that full body center of mass control is perturbed during such tasks. The purpose of this study was to compare the trunk and knee frontal plane moments and evaluate a relationship between the two during unanticipated cutting tasks. The results of this study suggest that there is a relationship between the trunk and knee frontal plane moments during the first 200-400ms of the stance phase of gait.

  4. Provocative mechanical tests of the peripheral nervous system affect the joint torque-angle during passive knee motion.

    Andrade, R J; Freitas, S R; Vaz, J R; Bruno, P M; Pezarat-Correia, P

    2015-06-01

    This study aimed to determine the influence of the head, upper trunk, and foot position on the passive knee extension (PKE) torque-angle response. PKE tests were performed in 10 healthy subjects using an isokinetic dynamometer at 2°/s. Subjects lay in the supine position with their hips flexed to 90°. The knee angle, passive torque, surface electromyography (EMG) of the semitendinosus and quadriceps vastus medialis, and stretch discomfort were recorded in six body positions during PKE. The different maximal active positions of the cervical spine (neutral; flexion; extension), thoracic spine (neutral; flexion), and ankle (neutral; dorsiflexion) were passively combined for the tests. Visual analog scale scores and EMG were unaffected by body segment positioning. An effect of the ankle joint was verified on the peak torque and knee maximum angle when the ankle was in the dorsiflexion position (P Upper trunk positioning had an effect on the knee submaximal torque (P cervical and thoracic spines were flexed (P angle response since different positions of head, upper trunk, and foot induce dissimilar knee mechanical responses during passive extension.

  5. A new protocol from real joint motion data for wear simulation in total knee arthroplasty: stair climbing.

    Battaglia, Santina; Belvedere, Claudio; Jaber, Sami Abdel; Affatato, Saverio; D'Angeli, Valentina; Leardini, Alberto

    2014-12-01

    In its normal lifespan, a knee prosthesis must bear highly demanding loading conditions, going beyond the sole activity of level walking required by ISO standard 14243. We have developed a protocol for in vitro wear simulation of stair climbing on a displacement controlled knee simulator. The flexion/extension angle, intra/extra rotation angle, and antero/posterior translation were obtained in patients by three-dimensional video-fluoroscopy. Axial load data were collected by gait analysis. Kinematics and load data revealed a good consistence across patients, in spite of the different prosthesis size. The protocol was then implemented and tested on a displacement controlled knee wear simulator, showing an accurate reproduction of stair climbing waveforms with a relative error lower than 5%.

  6. A prosthetic knee using magnetorhelogical fluid damper for above-knee amputees

    Park, Jinhyuk; Choi, Seung-Bok

    2015-04-01

    A prosthetic knee for above-knee (AK) amputees is categorized into two types; namely a passive and an active type. The passive prosthetic knee is generally made by elastic materials such as carbon fiber reinforced composite material, titanium and etc. The passive prosthetic knee easy to walk. But, it has disadvantages such that a knee joint motion is not similar to ordinary people. On the other hand, the active prosthetic knee can control the knee joint angle effectively because of mechanical actuator and microprocessor. The actuator should generate large damping force to support the weight of human body. But, generating the large torque using small actuator is difficult. To solve this problem, a semi-active type prosthetic knee has been researched. This paper proposes a semi-active prosthetic knee using a flow mode magneto-rheological (MR) damper for AK amputees. The proposed semi-active type prosthetic knee consists of the flow mode MR damper, hinge and prosthetic knee body. In order to support weight of human body, the required energy of MR damper is smaller than actuator of active prosthetic leg. And it can control the knee joint angle by inducing the magnetic field during the stance phase.

  7. Effect of Continuous Passive Motion on Pain and Range of Motion after Knee Arthroplasty%持续被动运动在膝关节置换术后早期康复治疗中的作用

    王东; 魏更生; 宋华伟; 蒋毅; 王艺伟; 吴磊

    2011-01-01

    Objective To evaluate the effect of continuous passive motion (CPM) as an adjunct to active physiotherapy on pain and range of motion (ROM) after knee arthroplasty. Methods 20 female osteoarthritis patients (40 knees) undergoing bilateral knee arthroplasty were assigned into two groups. The experimental group received CPM and active physiotherapy twice a day while the control group received active physiotherapy only. They were assessed with visual analogue scale (VAS) and goniometer on pain and ROM of knee before and after operation. Results There were no statistical difference between these two groups for any outcome measures either 2 weeks or 3 months after operation (P>0.05), and they all improved in pain and ROM 3 months after operation compared with before (P< 0.01). Conclusion CPM as an adjunctive therapy is not found to have an additional effect on pain or ROM 3 months after operation while active physiotherapy was used.%目的 评价持续被动运动(CPM)在膝关节置换术后早期康复治疗中对疼痛和膝关节主动屈伸活动度的作用.方法 20例(40膝)女性重度骨性关节炎患者行双膝关节同时置换术.分为实验组和对照组,每组10例20膝.实验组术后每天2次行CPM和主动康复治疗,对照组每天2次主动康复治疗.术前、术后2周和3个月应用疼痛视觉模拟评分(VAS)和角度测量仪评估两组患者的疼痛和膝关节主动屈伸活动度.结果 术后2周和3个月,两组患者的疼痛评分和膝关节活动度均无显著性差异(P>0.05).与术前相比,疼痛评分和膝关节主动屈伸活动度在术后3个月均有明显改善(P<0.01).结论 进行主动康复治疗后,CPM的辅助应用对膝关节置换术后3个月内疼痛和关节活动度的改善无明显促进作用.

  8. Effects of ankle joint mobilization with movement and weight-bearing exercise on knee strength, ankle range of motion, and gait velocity in patients with stroke: a pilot study.

    An, Chang-Man; Won, Jong-Im

    2016-01-01

    [Purpose] The purpose of this study was to investigate the effects of ankle joint mobilization with movement on knee strength, ankle range of motion, and gait velocity, compared with weight-bearing exercise in stroke patients. [Subjects and Methods] Thirty subjects with chronic stroke were divided into three groups: MWM (n = 12), WBE (n = 8), and control (n = 10). All groups attended physical therapy sessions 3 times a week for 5 weeks. Subjects in the MWM group performed mobilization with movement exercises, whilst participants in the WBE group performed weight-bearing exercises. Knee peak torque, ankle range of motion, and spatiotemporal gait parameters were evaluated before and after the interventions. [Results] Knee extensor peak torque increased significantly in both MWM and WBE groups. However, only the MWM group showed significant improvement in passive and active ankle range of motion and gait velocity, among the three groups. [Conclusion] Ankle joint mobilization with movement intervention is more effective than simple weight-bearing intervention in improving gait speed in stroke patients with limited ankle motion.

  9. Effects of Low-Impact Dance on Blood Biochemistry, Bone Mineral Density, the Joint Range of Motion of Lower Extremities, Knee Extension Torque, and Fall in Females.

    Wu, Hui Ying; Tu, Jui Hung; Hsu, Chin Hsing; Tsao, Te Hung

    2016-01-01

    The effect of low-impact dance on blood metabolites, the joint range of motion (ROM) of the lower extremities, knee extension torque, bone mass density (BMD), the number of falls, and the confidence to perform daily activities (Modified Falls Efficacy Scale [MFES]) was examined in older sedentary women (age: 59 ± 4 years) before and after a 16-week intervention. Results showed that the average score for the MFES, some parameters of blood chemistry, and joint ROM were significantly improved after low-impact intervention. In addition to improvements in blood lipids and body fat percentages, the increases shown in the parameters regarding the lower extremities may contribute to confidence in performing common daily activities in older women, although the number of falls did not significantly differ between the two groups during the 16-week period.

  10. Measurement of the screw-home motion of the knee is sensitive to errors in axis alignment.

    Piazza, S J; Cavanagh, P R

    2000-08-01

    Measurements of joint angles during motion analysis are subject to error caused by kinematic crosstalk, that is, one joint rotation (e. g., flexion) being interpreted as another (e.g., abduction). Kinematic crosstalk results from the chosen joint coordinate system being misaligned with the axes about which rotations are assumed to occur. The aim of this paper is to demonstrate that measurement of the so-called "screw-home" motion of the human knee, in which axial rotation and extension are coupled, is especially prone to errors due to crosstalk. The motions of two different two-segment mechanical linkages were examined to study the effects of crosstalk. The segments of the first linkage (NSH) were connected by a revolute joint, but the second linkage (SH) incorporated gearing that caused 15 degrees of screw-home rotation to occur with 90 degrees knee flexion. It was found that rotating the flexion axis (inducing crosstalk) could make linkage NSH appear to exhibit a screw-home motion and that a different rotation of the flexion axis could make linkage SH apparently exhibit pure flexion. These findings suggest that the measurement of screw-home rotation may be strongly influenced by errors in the location of the flexion axis. The magnitudes of these displacements of the flexion axis were consistent with the inter-observer variability seen when five experienced observers defined the flexion axis by palpating the medial and lateral femoral epicondyles. Care should be taken when interpreting small internal-external rotations and abduction-adduction angles to ensure that they are not the products of kinematic crosstalk.

  11. Comparing the Effects of Therapeutic Exercise and Hydrotherapy on Pain Severity and Knee Range of Motion in Patients with Hemophilia: A Randomized Controlled Trial

    V Mazloum

    2013-10-01

    . Results: Both experimental groups exhibited significant reduction of pain along with improved knee flexion and extension compared with the control group (P<0.001. Pain reduction in subjects treated in water treatment was significantly higher than exercise group in drought (P0.05. Conclusion: The use of therapeutic exercise in water with regular exercise rehabilitation for patients with hemophilia can be helpful to reduce pain and improve range of motion in hemophilia patients. The effect of exercise therapy on pain reduction is more effective compared to traditional pain therapy. Key words: Hydrotherapy, Exercise Therapy, Hemophilia, Knee Range of Motion

  12. Anterior cruciate ligament injury after more than 20 years: I. Physical activity level and knee function.

    Tengman, E; Brax Olofsson, L; Nilsson, K G; Tegner, Y; Lundgren, L; Häger, C K

    2014-12-01

    Little is known about physical activity level and knee function including jump capacity and fear of movement/reinjury more than 20 years after injury of the anterior cruciate ligament (ACL). Seventy persons with unilateral ACL injury participated (23 ± 2 years post-injury): 33 treated with physiotherapy in combination with surgical reconstruction (ACLR ), and 37 treated with physiotherapy alone (ACLPT ). These were compared with 33 age- and gender-matched controls. Assessment included knee-specific and general physical activity level [Tegner activity scale, International Physical Activity Questionnaire (IPAQ)], knee function [Lysholm score, Knee injury and Osteoarthritis Outcome Score (KOOS)], jump capacity (one-leg hop, vertical jump, side hops), and fear of movement/reinjury [Tampa Scale for Kinesiophobia (TSK)]. Outcomes were related to degree of osteoarthritis (OA). ACL-injured had lower Lysholm, KOOS, and Tegner scores than controls (P knee-related effects of ACL injury more than 20 years later.

  13. The remains of anterior cruciate ligament graft tension after cyclic knee motion

    Arnold, MR; Lie, DTT; Verdonschot, N; de Graaf, R; Amis, AA; van Kampen, A

    2005-01-01

    Background: There is sometimes a return of excess knee laxity after anterior cruciate ligament reconstruction. One of the contributing factors might be a loss in graft tension. It is unknown whether the tension imposed on an anterior cruciate ligament graft degrades with time and, if so, the effect

  14. Neuromuscular activity and knee kinematics in adolescents with patellofemoral pain

    Rathleff, Michael Skovdal; Samani, Afshin; Olesen, Jens L.;

    2013-01-01

    This study aimed to investigate the neuromuscular control of the knee during stair descent among female adolescents with patellofemoral pain (PFP) and to report its association with self-reported clinical status assessed by the Knee Injury and Osteoarthritis Outcome Score (KOOS).......This study aimed to investigate the neuromuscular control of the knee during stair descent among female adolescents with patellofemoral pain (PFP) and to report its association with self-reported clinical status assessed by the Knee Injury and Osteoarthritis Outcome Score (KOOS)....

  15. Influence of restricted vision and knee joint range of motion on gait properties during level walking and stair ascent and descent.

    Demura, Tomohiro; Demura, Shin-ich

    2011-01-01

    Because elderly individuals experience marked declines in various physical functions (e.g., vision, joint function) simultaneously, it is difficult to clarify the individual effects of these functional declines on walking. However, by imposing vision and joint function restrictions on young men, the effects of these functional declines on walking can be clarified. The authors aimed to determine the effect of restricted vision and range of motion (ROM) of the knee joint on gait properties while walking and ascending or descending stairs. Fifteen healthy young adults performed level walking and stair ascent and descent during control, vision restriction, and knee joint ROM restriction conditions. During level walking, walking speed and step width decreased, and double support time increased significantly with vision and knee joint ROM restrictions. Stance time, step width, and walking angle increased only with knee joint ROM restriction. Stance time, swing time, and double support time were significantly longer in level walking, stair descent, and stair ascent, in that order. The effects of vision and knee joint ROM restrictions were significantly larger than the control conditions. In conclusion, vision and knee joint ROM restrictions affect gait during level walking and stair ascent and descent. This effect is marked in stair ascent with knee joint ROM restriction.

  16. Muscle strength, physical performance and physical activity as predictors of future knee replacement

    Skou, Søren T; Wise, Barton L; Lewis, Cora E;

    2016-01-01

    OBJECTIVE: To investigate associations between lower levels of muscle strength, physical performance and physical activity and the risk of knee replacement (KR) in older adults with frequent knee pain. METHOD: Participants from the Multicenter Osteoarthritis Study (MOST) with knee pain on most...... of the past 30 days at baseline were included (n=1,257; mean (SD) age of 62.2 (8.2)). We examined the association between 1) baseline peak isokinetic knee extensor strength, (60°/sec, maximum out of 4 trials), 2) best time to stand in timed chair stand (2 trials of 5 repetitions), and 3) baseline Physical......% CI) 0.99 (0.99 to 1.00)), but not when adjusting for Kellgren-Lawrence grade (p = 0.97). CONCLUSION: Lower levels of chair stand performance and self-reported physical activity are not associated with an increased risk of KR within 7 years, while the independent effect of knee extensor strength...

  17. Motion

    Graybill, George

    2007-01-01

    Take the mystery out of motion. Our resource gives you everything you need to teach young scientists about motion. Students will learn about linear, accelerating, rotating and oscillating motion, and how these relate to everyday life - and even the solar system. Measuring and graphing motion is easy, and the concepts of speed, velocity and acceleration are clearly explained. Reading passages, comprehension questions, color mini posters and lots of hands-on activities all help teach and reinforce key concepts. Vocabulary and language are simplified in our resource to make them accessible to str

  18. A magnetorheological fluid-based controllable active knee brace

    Ahmadkhanlou, Farzad; Zite, Jamaal L.; Washington, Gregory N.

    2007-04-01

    High customization costs and reduction of natural mobility put current rehabilitative knee braces at a disadvantage. A resolution to this problem is to integrate a Magnetorheological (MR) fluid-based joint into the system. A MR joint will allow patients to apply and control a resistive torque to knee flexion and extension. The resistance torque can also be continuously adjusted as a function of extension angle and patient strength (or as a function of time), which is currently impossible with state of the art rehabilitative knee braces. A novel MR fluid-based controllable knee brace is designed and prototyped in this research. The device exhibits large resistive torque in the on-state and low resistance in the offstate. The controllable variable stiffness, compactness, and portability of the system make it a proper alternative to current rehabilitative knee braces.

  19. Geometric control of active collective motion

    Theillard, Maxime; Saintillan, David

    2016-01-01

    Recent experimental studies have shown that confinement can profoundly affect self-organization in semi-dilute active suspensions, leading to striking features such as the formation of steady and spontaneous vortices in circular domains and the emergence of unidirectional pumping motions in periodic racetrack geometries. Motivated by these findings, we analyze the two-dimensional dynamics in confined suspensions of active self-propelled swimmers using a mean-field kinetic theory where conservation equations for the particle configurations are coupled to the forced Navier-Stokes equations for the self-generated fluid flow. In circular domains, a systematic exploration of the parameter space casts light on three distinct states: equilibrium with no flow, stable vortex, and chaotic motion, and the transitions between these are explained and predicted quantitatively using a linearized theory. In periodic racetracks, similar transitions from equilibrium to net pumping to traveling waves to chaos are observed in ag...

  20. Water on the Knee

    ... your knee joint. Some people call this condition "water on the knee." A swollen knee may be ... Choose low-impact exercise. Certain activities, such as water aerobics and swimming, don't place continuous weight- ...

  1. Prosthesis alignment affects axial rotation motion after total knee replacement: a prospective in vivo study combining computed tomography and fluoroscopic evaluations

    Harman Melinda K

    2012-10-01

    Full Text Available Abstract Background Clinical consequences of alignment errors in total knee replacement (TKR have led to the rigorous evaluation of surgical alignment techniques. Rotational alignment in the transverse plane has proven particularly problematic, with errors due to component malalignment relative to bone anatomic landmarks and an overall mismatch between the femoral and tibial components’ relative positions. Ranges of nominal rotational alignment are not well defined, especially for the tibial component and for relative rotational mismatch, and some studies advocate the use of mobile-bearing TKR to accommodate the resulting small rotation errors. However, the relationships between prosthesis rotational alignment and mobile-bearing polyethylene insert motion are poorly understood. This prospective, in vivo study evaluates whether component malalignment and mismatch affect axial rotation motions during passive knee flexion after TKR. Methods Eighty patients were implanted with mobile-bearing TKR. Rotational alignment of the femoral and tibial components was measured from postoperative CT scans. All TKR were categorized into nominal or outlier groups based on defined norms for surgical rotational alignment relative to bone anatomic landmarks and relative rotational mismatch between the femoral and tibial components. Axial rotation motion of the femoral, tibial and polyethylene bearing components was measured from fluoroscopic images acquired during passive knee flexion. Results Axial rotation motion was generally accomplished in two phases, dominated by polyethylene bearing rotation on the tibial component in early to mid-flexion and then femoral component rotation on the polyethylene articular surface in later flexion. Opposite rotations of the femur-bearing and bearing-baseplate articulations were evident at flexion greater than 80°. Knees with outlier alignment had lower magnitudes of axial rotation and distinct transitions from external to

  2. RAPID KNEE-EXTENSIONS TO INCREASE QUADRICEPS MUSCLE ACTIVITY IN PATIENTS WITH TOTAL KNEE ARTHROPLASTY: A RANDOMIZED CROSS-OVER STUDY

    Wilquin, Lousia; Jakobsen, Thomas Linding; Holsgaard-Larsen, Anders; Bandholm, Thomas

    2017-01-01

    Background Inhibition of the quadriceps muscle and reduced knee-extension strength is common shortly following total knee arthroplasty (weeks to months), due to reduced voluntary activation of the quadriceps muscle. In healthy subjects, strength training with heavy loads is known to increase agonist muscle activity, especially if the exercise is conducted using rapid muscle contractions. Purpose The purpose of this study was to examine if patients with total knee arthroplasty could perform rapid knee-extensions using a 10 RM load four to eight weeks after surgery, and the degree to which rapid knee-extensions were associated with greater voluntary quadriceps muscle activity during an experimental strength training session, compared to that elicited using slow knee-extensions. Study Design A randomized cross-over study. Methods Twenty-four patients (age 66.5) 4-8 weeks post total knee arthroplasty randomly performed one set of five rapid, and one set of five slow knee-extensions with the operated leg, using a load of their 10 repetition maximum, while surface electromyography recordings were obtained from the vastus medialis and lateralis of the quadriceps muscle. Results Data from 23 of the 24 included patients were analyzed. Muscle activity was significantly higher during rapid knee-extensions (120.2% [10th-90th percentile: 98.3-149.1]) compared to slow knee-extensions (106.0% [88.8-140.8]) for the vastus lateralis (pknee-extensions were performed at a median angular velocity of 19.7 degrees/sec (13.7-24.4) and 51.4 degrees/sec (28.9-63.1), respectively Conclusion Four to eight weeks after their total knee arthroplasty, the patients in the present study were able to conduct rapid knee-extensions according to the experimental protocol with an approximately doubled angular velocity compared to slow knee-extensions. This was associated with increased muscle activity in the vastus lateralis when compared to slow knee-extensions, but not in the vastus medialis. Whether

  3. A magnetorheological fluid based orthopedic active knee brace

    Zite, Jamaal L.; Ahmadkhanlou, Farzad; Neelakantan, Vijay A.; Washington, Gregory N.

    2006-03-01

    The disadvantage of current knee braces ranges from high cost for customization to a loss in physical mobility and limited rehabilitative value. One approach to solving this problem is to use a Magnetorheological (MR) device to make the knee brace have a controllable resistance. Our design solution is to replace the manufacturer's joint with an rotary MR fluid based shear damper. The device is designed based on a maximum yield stress, a corresponding magnetic field, a torque and the MR fluid viscosity. The analytical and experimental results show the advantages and the feasibility of using the proposed MR based controllable knee braces.

  4. Superior results with continuous passive motion compared to active motion after periosteal transplantation. A retrospective study of human patella cartilage defect treatment.

    Alfredson, H; Lorentzon, R

    1999-01-01

    Fifty-seven consecutive patients (33 men and 24 women), with a mean age of 32 years (range 16-53 years), who suffered from an isolated full-thickness cartilage defect of the patella and disabling knee pain of long duration, were treated by autologous periosteal transplantation to the cartilage defect. The first 38 consecutive patients (group A) were postoperatively treated with continuous passive motion (CPM), and the next 19 consecutive patients (group B) were treated with active motion for the first 5 days postoperatively. In both groups, the initial regimens were followed by active motion, slowly progressive strength training, and slowly progressive weight bearing. In group A, after a mean follow-up of 51 months (range 33-92 months), 29 patients (76%) were graded as excellent or good, 7 patients (19%) were graded as fair, and 2 patients (5%) were graded as poor. In group B, after a mean follow-up of 21 months (range 14-28 months), 10 patients (53%) were graded as excellent or good, 6 patients (32%) were graded as fair, and 3 patients (15%) were graded as poor. Altogether, nine of the fair or poor cases (50%) were diagnosed with chondromalacia of the patella. Our results, after performing autologous periosteal transplantation in patients with full-thickness cartilage defects of the patella and disabling knee pain, are good if CPM is used postoperatively. The clinical results using active motion postoperatively are not acceptable, especially not in patients with chondromalacia of the patella.

  5. BLADE technology to eliminate MRI of knee joint motion artifacts%BLADE技术在消除MRI膝关节运动伪影方面的应用

    顾勇坚; 郑建刚; 许建兴; 刘良卿; 周鸿雁

    2012-01-01

    目的 探讨刀锋伪影校正(BLADE)技术在消除MRI膝关节运动伪影的应用价值.方法 32例膝关节常规MRI检查中出现运动伪影的患者,改用BLADE技术扫描(PD矢状位、T2矢状位),以是否能够清晰显示膝关节结构、半月板及交叉韧带为标准,与常规序列对比评估BLADE技术对消除膝关节运动伪影的应用价值.结果 膝关节常规序列扫描中出现运动伪影,改用BLADE技术扫描后,图像运动伪影消除,图像质量明显改善.结论 BLADE技术对膝关节常规扫描中产生的运动伪影有明显的校正作用,可广泛用于产生运动伪影的膝关节MRI检查中.%Objective To investigate the value of the blade artifact correction (BLADE) technology in eliminating the knee joint motion artifacts in the MR examination. Methods 32 patients with motion artifacts in the knee conventional MR examination were added standard BLADE technology to scan (PD sagittal, T2 sagittal), compared with conventional sequence, assessed the value of the BLADE technology to eliminate motion artifacts of the knee with a standard of clear display of the structure of the knee, meniscus and cruciate ligament. Results Switching to BLADE technology scanning, the image motion artifacts produced in the knee conventional examination was disappeared, and the image quality was improved significantly. Conclusion BLADE technology with significant role in correction the motion artifacts produced in the conventional scanning of the knee can be widely used to produce motion artifacts knee MRI examination.

  6. Comparison of the Cervical Extension Angle and the Upper Trapezius Muscle Activity between Overhead Work and Below-knee Work.

    Yoo, Won-Gyu

    2013-10-01

    [Purpose] The purpose of this study was to compare the cervical extension angle and the upper trapezius muscle activity between overhead work and below-knee work. [Subjects] Twelve males aged 20-30 years, were recruited. [Methods] We measured the cervical extension angle and upper trapezius muscle activity during overhead work and below-knee work. [Results] The results show that the cervical extension angle and upper trapezius muscle activity were significantly increased during below-knee work compared to overhead work. [Conclusion] Below-knee work is more likely to cause neck and shoulder pain than overhead work. Therefore, future studies should investigate below-knee work in detail.

  7. Displacement of the medial meniscus within the passive motion characteristics of the human knee joint: an RSA study in human cadaver knees.

    Tienen, T.G. van; Buma, P.; Scholten, J.G.; Kampen, A. van; Veth, R.P.H.; Verdonschot, N.J.J.

    2005-01-01

    The objective of this study was to validate an in vitro human cadaver knee-joint model for the evaluation of the meniscal movement during knee-joint flexion. The question was whether our model showed comparable meniscal displacements to those found in earlier meniscal movement studies in vivo. Furth

  8. Effect of generalized joint hypermobility on knee function and muscle activation in children and adults

    Jensen, Bente Rona; Olesen, Annesofie T.; Pedersen, Mogens Theisen

    2013-01-01

    were evaluated in 39 children and 36 adults during isometric knee extension and flexion. Subjects performed isometric maximum contractions, submaximal contractions at 25% maximum voluntary contraction (MVC), and explosive contractions. Results: Agonist activation was reduced, and coactivation ratio...

  9. Position controlled Knee Rehabilitation Orthotic Device for Patients after Total Knee Replacement Arthroplasty

    Wannaphan, Patsiri; Chanthasopeephan, Teeranoot

    2016-11-01

    Knee rehabilitation after total knee replacement arthroplasty is essential for patients during their post-surgery recovery period. This study is about designing one degree of freedom knee rehabilitation equipment to assist patients for their post-surgery exercise. The equipment is designed to be used in sitting position with flexion/extension of knee in sagittal plane. The range of knee joint motion is starting from 0 to 90 degrees angle for knee rehabilitation motion. The feature includes adjustable link for different human proportions and the torque feedback control at knee joint during rehabilitation and the control of flexion/extension speed. The motion of the rehabilitation equipment was set to move at low speed (18 degrees/sec) for knee rehabilitation. The rehabilitation link without additional load took one second to move from vertical hanging up to 90° while the corresponding torque increased from 0 Nm to 2 Nm at 90°. When extra load is added, the link took 1.5 seconds to move to 90° The torque is then increased from 0 Nm to 4 Nm. After a period of time, the speed of the motion can be varied. User can adjust the motion to 40 degrees/sec during recovery activity of the knee and users can increase the level of exercise or motion up to 60 degrees/sec to strengthen the muscles during throughout their rehabilitation program depends on each patient. Torque control is included to prevent injury. Patients can use the equipment for home exercise to help reduce the number of hospital visit while the patients can receive an appropriate therapy for their knee recovery program.

  10. Does the Q − H index show a stronger relationship than the H:Q ratio in regard to knee pain during daily activities in patients with knee osteoarthritis?

    Fujita, Remi; Matsui, Yasumoto; Harada, Atsushi; Takemura, Marie; Kondo, Izumi; Nemoto, Tetsuya; Sakai, Tadahiro; Hiraiwa, Hideki; Ota, Susumu

    2016-01-01

    [Purpose] The purpose of this study was to elucidate the relationship between knee muscle strength and knee pain in activities of daily living, based on consideration of the difference between extension and flexion strength (Q − H) and the hamstring:quadriceps (H:Q) ratio in patients with knee osteoarthritis. [Subjects and Methods] The participants were 78 females with knee osteoarthritis, and a total of 133 knees that had not been treated surgically were the targets of this research. The legs were divided according to dominance. Isometric knee extension and flexion muscle strength and knee pain during activities of daily living were measured. The H:Q ratio (flexion/extension muscle strength) and the difference between extension and flexion strength, (extension muscle strength/weight) minus (flexion muscle strength/weight), that is, Q − H, were calculated. The correlation between these indices and the knee pain score during activities of daily living was investigated. [Results] Greater knee pain during activities of daily living was related to lower knee extension muscle strength and Q − H in both the dominant and nondominant legs. Knee flexion muscle strength and the H:Q ratio were not significantly correlated with knee pain during any activities of daily living. [Conclusion] Knee extension muscle strength and Q − H were found to be significantly correlated with knee pain during activities of daily living, whereas the H:Q ratio was not. PMID:28174444

  11. Testosterone Reduces Knee Passive Range of Motion and Expression of Relaxin Receptor Isoforms via 5α-Dihydrotestosterone and Androgen Receptor Binding

    Firouzeh Dehghan

    2014-03-01

    Full Text Available Ovarian steroids such as estrogen and progesterone have been reported to influence knee laxity. The effect of testosterone, however, remains unknown. This study investigated the effect of testosterone on the knee range of motion (ROM and the molecular mechanisms that might involve changes in the expression of relaxin receptor isoforms, Rxfp1 and Rxfp2 in the patella tendon and lateral collateral ligament of the female rat knee. Ovariectomized adult female Wistar rats received three days treatment with peanut oil (control, testosterone (125 and 250 μg/kg and testosterone (125 and 250 μg/kg plus flutamide, an androgen receptor blocker or finasteride, a 5α-reductase inhibitor. Duplicate groups received similar treatment however in the presence of relaxin (25 ng/kg. A day after the last drug injection, knee passive ROM was measured by using a digital miniature goniometer. Both tendon and ligament were harvested and then analysed for protein and mRNA expression for Rxfp1 and Rxfp2 respectively. Knee passive ROM, Rxfp1 and Rxfp2 expression were significantly reduced following treatment with testosterone. Flutamide or finasteride administration antagonized the testosterone effect. Concomitant administration of testosterone and relaxin did not result in a significant change in knee ROM as compared to testosterone only treatment; however this was significantly increased following flutamide or finasteride addition. Testosterone effect on knee passive ROM is likely mediated via dihydro-testosterone (DHT, and involves downregulation of Rxfp1 and Rxfp2 expression, which may provide the mechanism underlying testosterone-induced decrease in female knee laxity.

  12. Effect of a high intensity quadriceps fatigue protocol on knee joint mechanics and muscle activation during gait in young adults.

    Murdock, Gillian Hatfield; Hubley-Kozey, Cheryl L

    2012-02-01

    The purpose of this study was to determine the effect of impaired quadriceps function on knee joint biomechanics and neuromuscular function during gait. Surface electromyograms, three-dimensional motion and ground reaction forces were collected during gait before and after 20 healthy adults completed a high intensity quadriceps fatigue protocol. Pattern recognition techniques were utilized to examine changes in amplitude and temporal characteristics of all gait variables. The fatigue protocol resulted in decreased knee extensor torque generation and quadriceps median power frequencies for 18 of 20 participants (p gait data from these 18 participants was analyzed. The knee external rotation angle increased (p knee motion and loading characteristics were altered following a high intensity fatigue protocol in a manner that may place the knee joint at greater risk for joint pathology and injury.

  13. Physiological alterations of maximal voluntary quadriceps activation by changes of knee joint angle.

    Becker, R; Awiszus, F

    2001-05-01

    The purpose of this study was to investigate the influence of different angles of the knee joint on voluntary activation of the quadriceps muscle, estimating the ability of a subject to activate a muscle maximally by means of voluntary contraction. Isometric torque measurement was performed on 6 healthy subjects in 5 degrees intervals between 30 degrees and 90 degrees of knee joint flexion. Superimposed twitches at maximal voluntary contraction (MVC) and at a level of 60% and 40% of the MVC were applied and the voluntary activation estimated. At between 30 degrees and 75 degrees of knee flexion, the maximal extension torque increased at an average rate of 2.67 +/- 0.6 Nm/degree, followed by a decline with further flexion. However, throughout the joint-angle range tested, voluntary activation increased on average by 0.37%/degree with a maximum at 90 degrees of flexion. Due to the influence of joint position it is not possible to generalize results obtained at the knee joint angle of 90 degrees of flexion, which is usually used for the quadriceps twitch-interpolation technique. Consequently, it is useful to investigate voluntary activation deficits in knee joint disorders at a range of knee joint angles that includes, in particular, the more extended joint angles used frequently during daily activity.

  14. An ex vivo continuous passive motion model in a porcine knee for assessing primary stability of cell-free collagen gel plugs

    El-Zayat Bilal

    2010-12-01

    Full Text Available Abstract Background Primary stability of cartilage repair constructs is of the utmost importance in the clinical setting but few continuous passive motion (CPM models are available. Our study aimed to establish a novel ex vivo CPM animal model and to evaluate the required motion cycles for testing the mechanical properties of a new cell-free collagen type I gel plug (CaReS®-1S. Methods A novel ex vivo CPM device was developed. Full-thickness cartilage defects (11 mm diameter by 6 mm deep were created on the medial femoral condyle of porcine knee specimens. CaReS®-1S was implanted in 16 animals and each knee underwent continuous passive motion. After 0, 2000, 4000, 6000, and 8000 motions, standardized digital pictures of the grafts were taken, focusing on the worn surfaces. The percentage of worn surface on the total CaReS®-1S surface was evaluated with image processing software. Results Significant differences in the worn surface were recorded between 0 and 2000 motion cycles (p ®-1S with an empty defect site was recorded. Conclusion The ex vivo CPM animal model is appropriate in investigating CaReS®-1S durability under continuous passive motion. 2000 motion cycles appear adequate to assess the primary stability of type I collagen gels used to repair focal chondral defects.

  15. Astym® Therapy for the Management of Recalcitrant Knee Joint Stiffness after Total Knee Arthroplasty.

    Bhave, Anil; Corcoran, James; Cherian, Jeffery J; Mont, Michael A

    2016-01-01

    Knee stiffness is a common complication after total knee arthroplasty (TKA). Despite studies published on the surgical management of reduced range of motion (ROM) after TKA, there is limited evidence on the nonoperative management of joint and soft tissue imbalances possibly contributing to reduced knee ROM. This report assesses changes in ROM, pain, function, and patellar tendon length after Astym® joint mobilization use. A 38-year-old male professional skier had a right TKA 3 months before presentation with 2 subsequent manipulations under anesthesia secondary to persistent knee stiffness. He had patellar baja on radiograph, a reduced arc of ROM, reduced patellar mobility and muscular extensibility, and pain to palpation along the patellar tendon. He had 12 visits of physical therapy with the use of Astym®, patellar mobilization, and tibio-femoral mobilizations with movement. The patient also used a customized knee device at home for prolonged knee extension stretching. The patient was treated for 12 visits, along with home use of customized bracing for knee extension. Significant improvements were seen in pain, function, and ROM. He returned to work full-time, ambulated prolonged distances, and negotiated stairs pain-free. He also demonstrated resolution of patellar baja radiographically. Conservative management of recalcitrant knee joint stiffness after primary TKA can be effective in restoring knee mobility and reducing pain and activity limitation. A multimodal approach using Astym® treatment, customized knee bracing, and targeted joint mobilization can be effective in resolving knee joint stiffness.

  16. Role of flexors in knee stability.

    Chen, C Y; Jiang, C C; Jan, M H; Lai, J S

    1995-05-01

    The muscle strength of knee extensors is commonly used as an indicator of a patient's functional recovery following reconstruction of the anterior cruciate ligament (ACL). The knee flexors are dynamic stabilizers that prevent tibial anterior displacement and may reinforce the function of the ACL. The purpose of this study was to examine the relationship of knee flexor performance assessed by isokinetic dynamometer and clinical evaluations including KT-1000 stability tests, shuttle run tests, thigh and calf circumference and range of motion of the knee joint. Ten patients who received ACL reconstruction over a 3- to 5-year period were included in this study, as were 15 normal controls who were tested for comparison. There was no significant difference in the time taken for the shuttle run test between normal controls and patients who underwent ACL, but there was a positive correlation between the shuttle run test and laxity of the knee joint. The knee laxity of ACL patients was significantly greater than that of the normal controls under passive anterior force. However, no significant difference was seen in the stability test under active contraction of the knee extensors. In addition, a positive correlation was seen between the KT-1000 knee ligament arthrometry test results and both torque acceleration energy and the average power of the flexors. These results suggest that physical therapy for patients following ACL reconstruction should emphasize the explosiveness of knee flexors to help strengthen the dynamic stability of the knee joint and motor performance.

  17. [CPM--Continuous Passive Motion: treatment of injured or operated knee-joints using passive movement. A meta-analysis of current literature].

    Kirschner, P

    2004-04-01

    There is still a controversial discussion in literature about the use of motor driven splints in knee surgery--as the principle of continuous passive motion, CPM. For this reason it seemed useful for an evaluation to look through the papers which were published since 1990. It was obvious, that negative results were published often before this year, but this papers are still quoted standard works. In medical data bases subito-doc.de, medscape.com, medica.de and zbmed.de 230 papers were found by search CPM, continuous passive motion and arthromot. Coincidentally there was a search for authors who were already quoted in other papers. 36 papers concerning CPM after knee surgery were utilized. The role of CPM regarding the range of motion, swelling, duration of hospital stay, use of analgesics, costs, postoperative manipulations, wound healing and thrombo embolic complications was evaluated. Although the results of this partial retrospective, partial prospective, sometimes randomized or double blinded studies are in contradiction, there can only be found a trend to better results. New clinical studies for evidence based guidelines in the handling of continuous passive motion after knee surgery are necessary.

  18. Comparison of the Cervical Extension Angle and the Upper Trapezius Muscle Activity between Overhead Work and Below-knee Work

    Yoo, Won-gyu

    2013-01-01

    [Purpose] The purpose of this study was to compare the cervical extension angle and the upper trapezius muscle activity between overhead work and below-knee work. [Subjects] Twelve males aged 20–30 years, were recruited. [Methods] We measured the cervical extension angle and upper trapezius muscle activity during overhead work and below-knee work. [Results] The results show that the cervical extension angle and upper trapezius muscle activity were significantly increased during below-knee wor...

  19. Design and control of a prosthetic leg for above-knee amputees operated in semi-active and active modes

    Park, Jinhyuk; Yoon, Gun-Ha; Kang, Je-Won; Choi, Seung-Bok

    2016-08-01

    This paper proposes a new prosthesis operated in two different modes; the semi-active and active modes. The semi-active mode is achieved from a flow mode magneto-rheological (MR) damper, while the active mode is obtained from an electronically commutated (EC) motor. The knee joint part of the above knee prosthesis is equipped with the MR damper and EC motor. The MR damper generates reaction force by controlling the field-dependent yield stress of the MR fluid, while the EC motor actively controls the knee joint angle during gait cycle. In this work, the MR damper is designed as a two-end type flow mode mechanism without air chamber for compact size. On other hand, in order to predict desired knee joint angle to be controlled by EC motor, a polynomial prediction function using a statistical method is used. A nonlinear proportional-derivative controller integrated with the computed torque method is then designed and applied to both MR damper and EC motor to control the knee joint angle. It is demonstrated that the desired knee joint angle is well achieved in different walking velocities on the ground ground.

  20. Vitality and the course of limitations in activities in osteoarthritis of the hip or knee

    van Dijk Gabriella M

    2011-11-01

    Full Text Available Abstract Background The objective of the study was to determine whether psychological and social factors predict the course of limitations in activities in elderly patients with osteoarthritis of the hip or knee, in addition to established somatic and cognitive risk factors. Methods A longitudinal cohort study with a follow-up period of three years was conducted. Patients (N = 237 with hip or knee osteoarthritis were recruited from rehabilitation centers and hospitals. Body functions, comorbidity, cognitive functioning, limitations in activities and psychological and social factors (mental health, vitality, pain coping and perceived social support were assessed. Statistical analyses included univariate and multivariate regression analyses. Psychological and social factors were added to a previously developed model with body functions, comorbidity and cognitive functioning. Results In knee OA, low vitality has a negative impact on the course of self-reported and performance-based limitations in activities, after controlling for somatic and cognitive factors. In hip OA, psychological and social factors had no additional contribution to the model. Conclusion Low vitality predicts deterioration of limitations in activities in elderly patients with osteoarthritis of the knee, in addition to established somatic and cognitive risk factors. However, the contribution of vitality is relatively small. Results of this study are relevant for the group of patients with knee or hip OA, attending hospitals and rehabilitation centers.

  1. Video shot boundary detection using motion activity descriptor

    Amel, Abdelati Malek; Abdellatif, Mtibaa

    2010-01-01

    This paper focus on the study of the motion activity descriptor for shot boundary detection in video sequences. We interest in the validation of this descriptor in the aim of its real time implementation with reasonable high performances in shot boundary detection. The motion activity information is extracted in uncompressed domain based on adaptive rood pattern search (ARPS) algorithm. In this context, the motion activity descriptor was applied for different video sequence.

  2. Changes in the activity of trunk and hip extensor muscles during bridge exercises with variations in unilateral knee joint angle

    Kim, Juseung; Park, Minchul

    2016-01-01

    [Purpose] This study compared abdominal and hip extensor muscle activity during a bridge exercise with various knee joint angles. [Subjects and Methods] Twenty-two healthy male subjects performed a bridge exercise in which the knee joint angle was altered. While subjects performed the bridge exercise, external oblique, internal oblique, gluteus maximus, and semitendinosus muscle activity was measured using electromyography. [Results] The bilateral external and internal oblique muscle activity was significantly higher at 0° knee flexion compared to 120°, 90°, and 60°. The bilateral gluteus maximus muscle activity was significantly different at 0° of knee flexion compared to 120°, 90°, and 60°. The ipsilateral semitendinosus muscle activity was significantly increased at 90° and 60° of knee flexion compared to 120°, and significantly decreased at 0° knee flexion compared with 120°, 90°, and 60°. The contralateral semitendinosus muscle activity was significantly higher at 60° of knee flexion than at 120°, and significantly higher at 0° of knee flexion than at 120°, 90°, and 60°. [Conclusion] Bridge exercises performed with knee flexion less than 90° may be used to train the ipsilateral semitendinosus. Furthermore, bridge exercise performed with one leg may be used to train abdominal and hip extensor muscles. PMID:27799688

  3. Single- vs. double-bundle anterior cruciate ligament reconstruction: a new aspect of knee assessment during activities involving dynamic knee rotation.

    Czamara, Andrzej; Królikowska, Aleksandra; Szuba, Łukasz; Widuchowski, Wojciech; Kentel, Maciej

    2015-02-01

    Few studies have compared single-bundle (SB) and double-bundle (DB) anterior cruciate ligament reconstruction (ACLR) in the knee joint during activities involving change-of-direction maneuvers and knee rotation. This study examined whether the type of ACLR contributes to postphysiotherapy outcomes, with an emphasis on knee function assessment during activities involving dynamic knee rotation. Fifteen male patients after SB ACLR and 15 male patients after DB ACLR took part in the same physiotherapy program. Twenty-four weeks after ACLR, both groups underwent anterior laxity measurement, pivot shift tests, range of movement and joint circumference measurements, subjective assessment of pain and stability levels in the knee joint, peak torque measurement of the muscles rotating the tibia toward the femur, and a run test with maximal speed and change-of-direction maneuvers. Comparative analysis did not show any differences between the results of anterior tibial translation, pivot shift test, range of movement and joint circumference, and subjective assessment of pain and knee joint stability levels. No differences were noted between the groups in peak torque values obtained from the muscles responsible for internal and external tibial rotation or results of the run test. The data obtained from this study can be used by research teams to monitor and compare the effectiveness of various study protocols involving surgical and physiotherapy treatment. The data are especially useful when combined with the clinical assessment of patients who would like to return to sport.

  4. Self-reported activity level and knee function in amateur football players

    Frobell, R B; Svensson, E; Göthrick, M;

    2008-01-01

    The aim of this study is to investigate if self-reported activity level or knee functions are influenced by subject characteristics, level of competition and history of knee injury. Cross-Sectional study using questionnaires distributed at a personal visit. One hundred and eighty-eight (65 women......) amateur football players in 10 football clubs from each division below national level participated in the study. Self-reported Tegner Activity Scale, and the Knee injury and Osteoarthritis Outcome Score (KOOS) are the main outcome measures. Older age, female gender and lower level of competition (football...... is recommended. We suggest that self-reported Tegner Activity Scale scores should be adjusted for age, gender and level of competition. In amateur football players, KOOS scores do not need adjustment for age and gender....

  5. Physical Activity Participation Among Patients After Total Hip and Knee Arthroplasty

    Stevens, Martin; Reininga, Inge H. F.; Bulstra, Sjoerd K.; Wagenmakers, Robert; van den Akker-Scheek, Inge

    2012-01-01

    Total hip (THA) and knee arthroplasty (TKA) are successful operative interventions, yet little is known about the physical activity behavior of patients after THA/TKA. For older adults, there are beneficial effects of regular physical activity after THA/TKA. The objective of this paper is to review

  6. Prospective Randomized Trial of the Efficacy of Continuous Passive Motion Post Total Knee Arthroplasty: Experience of the Hospital for Special Surgery.

    Joshi, Rupali N; White, Peter B; Murray-Weir, Mary; Alexiades, Michael M; Sculco, Thomas P; Ranawat, Amar S

    2015-12-01

    Conflicting evidence has created substantial controversy regarding the use of continuous passive motion (CPM) in the in-patient setting post total knee arthroplasty (TKA). A total of 109 patients were randomly assigned to two groups, CPM or no CPM, applied after TKA. All patients received the same physical therapy protocol (3 sessions per day), with the only exception being the CPM. Both groups had a knee flexion of 115° at 6 weeks and 120° at 3 months, with no significant differences (P=0.69 and P=0.41, respectively). Length of stay was significantly less for the group who did not receive CPM. The use of CPM had no clinically relevant benefits with respect to AROM, clinical outcomes or discharge disposition and was associated with a cost of $235.50 per TKA.

  7. Women with knee osteoarthritis have more pain and poorer function than men, but similar physical activity prior to total knee replacement

    Tonelli Shalome M

    2011-11-01

    Full Text Available Abstract Background Osteoarthritis of the knee is a major clinical problem affecting a greater proportion of women than men. Women generally report higher pain intensity at rest and greater perceived functional deficits than men. Women also perform worse than men on function measures such as the 6-minute walk and timed up and go tests. Differences in pain sensitivity, pain during function, psychosocial variables, and physical activity levels are unclear. Further the ability of various biopsychosocial variables to explain physical activity, function and pain is unknown. Methods This study examined differences in pain, pain sensitivity, function, psychosocial variables, and physical activity between women and men with knee osteoarthritis (N = 208 immediately prior to total knee arthroplasty. We assessed: (1 pain using self-report measures and a numerical rating scale at rest and during functional tasks, (2 pain sensitivity using quantitative sensory measures, (3 function with self-report measures and specific function tasks (timed walk, maximal active flexion and extension, (4 psychosocial measures (depression, anxiety, catastrophizing, and social support, and (5 physical activity using accelerometry. The ability of these mixed variables to explain physical activity, function and pain was assessed using regression analysis. Results Our findings showed significant differences on pain intensity, pain sensitivity, and function tasks, but not on psychosocial measures or physical activity. Women had significantly worse pain and more impaired function than men. Their levels of depression, anxiety, pain catastrophizing, social support, and physical activity, however, did not differ significantly. Factors explaining differences in (1 pain during movement (during gait speed test were pain at rest, knee extension, state anxiety, and pressure pain threshold; (2 function (gait speed test were sex, age, knee extension, knee flexion opioid medications, pain

  8. Loading of the knee joint during activities of daily living measured in vivo in five subjects.

    Kutzner, I; Heinlein, B; Graichen, F; Bender, A; Rohlmann, A; Halder, A; Beier, A; Bergmann, G

    2010-08-10

    Detailed knowledge about loading of the knee joint is essential for preclinical testing of implants, validation of musculoskeletal models and biomechanical understanding of the knee joint. The contact forces and moments acting on the tibial component were therefore measured in 5 subjects in vivo by an instrumented knee implant during various activities of daily living. Average peak resultant forces, in percent of body weight, were highest during stair descending (346% BW), followed by stair ascending (316% BW), level walking (261% BW), one legged stance (259% BW), knee bending (253% BW), standing up (246% BW), sitting down (225% BW) and two legged stance (107% BW). Peak shear forces were about 10-20 times smaller than the axial force. Resultant forces acted almost vertically on the tibial plateau even during high flexion. Highest moments acted in the frontal plane with a typical peak to peak range -2.91% BWm (adduction moment) to 1.61% BWm (abduction moment) throughout all activities. Peak flexion/extension moments ranged between -0.44% BWm (extension moment) and 3.16% BWm (flexion moment). Peak external/internal torques lay between -1.1% BWm (internal torque) and 0.53% BWm (external torque). The knee joint is highly loaded during daily life. In general, resultant contact forces during dynamic activities were lower than the ones predicted by many mathematical models, but lay in a similar range as measured in vivo by others. Some of the observed load components were much higher than those currently applied when testing knee implants.

  9. Instabilities, motion and deformation of active fluid droplets

    Whitfield, Carl A.; Hawkins, Rhoda J.

    2016-12-01

    We consider two minimal models of active fluid droplets that exhibit complex dynamics including steady motion, deformation, rotation and oscillating motion. First we consider a droplet with a concentration of active contractile matter adsorbed to its boundary. We analytically predict activity driven instabilities in the concentration profile, and compare them to the dynamics we find from simulations. Secondly, we consider a droplet of active polar fluid of constant concentration. In this system we predict, motion and deformation of the droplets in certain activity ranges due to instabilities in the polarisation field. Both these systems show spontaneous transitions to motility and deformation which resemble dynamics of the cell cytoskeleton in animal cells.

  10. Effect of shoes containing nanosilica particles on knee valgus in active females during landing

    Zahra Bassiri

    2015-01-01

    Full Text Available Objective(s: The effect of silica nanoparticles (SNPs in sport shoes outsoles on the  parameters related to anterior cruciate ligament (ACL Injury has not been investigated. The aim of this study was to investigate the effect of shoes outsole containing a composite of thermoplastic elastomer based on styrene-butadiene and silica nanoparticles (TPEN shoe on Knee Valgus Angle (KVA as a risk factor of ACL injuries during landing Materials and Methods: Fourteen active healthy women without knee injuries and disorders performed bilateral drop jump (DJ and single leg drop landing (SLL tasks in barefoot, wearing shoes fabricated with polyvinyl chloride outsole (PVC shoe and TPEN shoes conditions , randomly. The knee valgus angle values of right and left legs were calculated in the landing conditions. Two factors repeated measures ANOVA were used to investigate the effect of landing and footwear conditions on KVA of right and left legs.  Results: For both left and right limbs, the KVA was at maximum and minimum values during landing with barefoot and TPEN shoes, respectively. PVC shoe significantly reduced the knee valgus by 3.84% in left and 4.18% in right knee (P

  11. 人工全膝关节置换后关节活动度影响因素的研究趋势%Research trend of factors influencing range of motion after artificial total knee replacement

    王九辉

    2012-01-01

    背景:人工全膝关节置换后关节活动度是评价患者对治疗是否满意的关键,是患者膝关节功能恢复的主要观察指标.目的:分析人工全膝关节置换后关节活动度研究领域的发展趋势,探讨人工全膝关节置换后关节活动度的影响因素.方法:由作者用计算机检索CNKI数据库2002/2011收录的有关人工全膝关节置换后关节活动度的相关文献,检索时间为2002/2011,中文检索词为"膝关节,人工关节,人工假体,关节活动度",英文检索词为"knee,artificial joint,prosthesis,range of motion".共检索到244篇文章,按纳入标准和排除标准对文献进行筛选和分析,共纳入211篇文章.从膝关节置换前膝关节活动度、人工假体类型和置换后康复训练等方面来分析其影响因素.结果与结论:近10年来,CNKI数据库学术期刊收录膝关节置换后关节活动度研究文献数量呈上升趋势,2010年发表文献量最多为38篇,占总文献量的18.0%;从检索的关键词可见膝关节置换在骨关节炎疾病的治疗中应用最多;相关研究文献的基金资助项目较少;<中国组织工程研究与临床康复>杂志因设有硬组织植入物栏目,发表的相关文献量最多为41篇,占全部文献量的19.4%.文献计量学的分析为中国从事人工全膝关节置换的临床医务工作者提供更有价值的参考信息,影响人工全膝关节置换后关节活动度因素有很多,而且存在很多争议,临床医生应该不断提高治疗技术和康复训练方法,尽可能的恢复患者的膝关节活动功能.%BACKGROUND: Range of motion after artificial total knee replacement is the key to evaluate whether the patients are satisfied with the treatment or not, as well as the main outcome measures of functional recovery of joint knee.OBJECTIVE: To analyze the trends in the field of joint activity after artificial total knee replacement and to explore the influence factors of joint activity

  12. Medium-term evaluation of total knee arthroplasty without patellar replacement

    José Wanderley Vasconcelos

    2013-06-01

    Full Text Available OBJECTIVE: To mid-term evaluate patients who were submitted to total knee arthroplasty without patellar resurfacing. METHODS: It was realized a retrospective cross-sectional study of patients who were submitted to total knee arthroplasty without patellar resurfacing. In all patients clinical examination was done based on the protocol of the Knee Society Scoring System, which assessed pain, range of motion, stability, contraction, knee alignment and function, and radiological evaluation. RESULTS: A total of 36 patients were evaluated. Of these, 07 were operated only on left knee, 12 only on right knee and 17 were operated bilaterally, totaling 53 knees. Ages ranged from 26 to 84 years. Of the 53 knees evaluated, 33 (62.26% had no pain. The maximum flexion range of motion averaged 104.7°. No knee had difficulty in active extension. As to the alignment for anatomical axis twelve knees (22.64% showed deviation between 0° and 4° varus. Thirty-nine (75.49% knees showed pace without restriction and the femorotibial angle ranged between 3° varus and 13° valgus with an average of 5° valgus. The patellar index ranged from 0.2 to 1.1. CONCLUSION: Total knee arthroplasty whitout patellar resurfacing provides good results in mid-term evaluation.

  13. Which patients with osteoarthritis of hip and/or knee benefit most from behavioral graded activity?

    Veenhof, C.; Ende, C.H.M. van den; Dekker, J.; Kiike, A.J.; Oostendorp, R.A.B.; Bijlsma, J.W.J.

    2007-01-01

    Our objective was to investigate whether behavioral graded activity (BGA) has particular benefit in specific subgroups of osteoarthritis (OA) patients. Two hundred participants with OA of hip or knee, or both (clinical American College of Rheumatology, ACR, criteria) participated in a randomized cli

  14. Which patients with osteoarthritis of hip and/or knee benefit most from behavorial graded activity?

    Veenhof, C.; Ende, C.H.M. van den; Dekker, J.; Köke, A.J.A.; Oostendorp, R.A.; Bijlsma, J.W.J.

    2007-01-01

    Our objective was to investigate whether behavioral graded activity (BGA) has particular benefit in specific subgroups of osteoarthritis (OA) patients. Two hundred participants with OA of hip or knee, or both (clinical American College of Rheumatology, ACR, criteria) participated in a randomized cli

  15. Activity, Sleep and Cognition After Fast-Track Hip or Knee Arthroplasty

    Krenk, Lene; Jennum, Poul; Kehlet, Henrik

    2013-01-01

    Optimized perioperative care after total hip and knee arthroplasty (THA/TKA) has decreased length of stay (LOS) but data on activity, sleep and cognition after discharge are limited. We included 20 patients ≥60years undergoing THA/TKA, monitoring them for 3days preoperatively and 9days postoperat...

  16. Increased muscle activity to stabilise mobile bearing knees in patients with rheumatoid arthritis

    Garling, E.H.; Eck, M; Wedding, T.; Veeger, H.E.J.; Valstar, E.R.; Nelissen, R.G.H.H.

    2005-01-01

    The aim of this study was to assess the differences in muscle activity (surface EMG) between a posterior stabilised (PS) total knee design and a mobile bearing (MB) posterior cruciate ligament retaining design in rheumatoid arthritis (RA) patients during a step-up task. Four patients with a PS total

  17. Differences between actual and expected leisure activities after total knee arthroplasty for osteoarthritis.

    Jones, Dina L; Bhanegaonkar, Abhijeet J; Billings, Anthony A; Kriska, Andrea M; Irrgang, James J; Crossett, Lawrence S; Kwoh, C Kent

    2012-08-01

    This prospective cohort study determined the type, frequency, intensity, and duration of actual vs expected leisure activity among a cohort undergoing total knee arthroplasty. Data on actual and expected participation in 36 leisure activities were collected preoperatively and at 12 months in 90 patients with knee osteoarthritis. Despite high expectations, there were statistically and clinically significant differences between actual and expected activity at 12 months suggesting that expectations may not have been fulfilled. The differences were equivalent to walking 14 less miles per week than expected, which is more than the amount of activity recommended in national physical activity guidelines. Perhaps an educational intervention could be implemented to help patients establish appropriate and realistic leisure activity expectations before surgery.

  18. Short-term follow-up of total knee arthroplasty with LPS-Flex Mobile Bearing System knee prosthesis:range of motion of knee joint and function evaluation%高屈曲旋转平台型假体全膝关节置换的近期随访:膝关节活动度及功能评价

    吴广鹏; 徐耀增; 朱永生; 朱锋; 邵洪国; 李荣群; 周军

    2015-01-01

    -Flex Mobile Bearing system artificial knee prosthesis (Zimmer, USA), and to assess the biocompatibility of artificial prosthesis and host using range of motion of knee and function after replacement. METHODS:We retrospectively analyzed 37 patients (42 knees) undergoing total knee arthroplasty using Zimmer LPS-Flex Mobile Bearing prostheses (high-flexion rotating platform type knee prosthesis) in The First Hospital Affiliated to Soochow University from February 2012 to March 2014, including 9 males (10 knees) and 28 females (32 knees), aged 47-78 years, averagely 63.7 years. Bone cement fixation was used, and the patel a was not treated with replacement. Postoperative complications were observed. Ranges of motion of knee joint preoperatively and postoperatively were compared. The recovery of knee joint function was evaluated using Hospital for Special Surgery Knee Score. RESULTS AND CONCLUSION:A total of 34 cases (38 knees) were fol owed up for 6-28 months. Range of motion of knee joint improved from 88.5° before operation to 124.2° after operation on average. Hospital for Special Surgery Knee Score improved from 52.5 before replacement to 91.1 after replacement, showing significant differences (P<0.01). Therapeutic effects were assessed according to Hospital for Special Surgery Knee Score:excel ent in 20 cases, good in 16 cases, average in 2 cases, with an excel ent and good rate of 95%. The incidence of various complications was low. These data suggested that short-period clinical outcomes of high-flexion rotating platform type knee prosthesis replacement are satisfactory. This prosthesis has advantages in its design, which is more close to the physical structure of knee joint, but its long-period outcomes deserve further investigations.

  19. Acute effects of instrument assisted soft tissue mobilization vs. foam rolling on knee and hip range of motion in soccer players.

    Markovic, Goran

    2015-10-01

    The aim of the present investigation was to evaluate the acute effects of foam rolling (FR) and a new form of instrument-assisted soft tissue mobilization (IASTM), Fascial Abrasion Technique ™ (FAT) on hip and knee range of motion in soccer players. Twenty male soccer players randomly allocated into FR and FAT group (n = 10 each). Passive knee flexion and straight leg raise tests were measured before, immediately after and 24 h after intervention (FR or FAT). The FR group applied a 2-min quadriceps and hamstrings rolling, while FAT group received a 2-min application of FAT to the quadriceps and hamstrings muscles. Both groups significantly improved knee and hip ROM (p < 0.05), with higher gains observed in FAT group (10-19% vs. 5-9%). At 24 h post-treatment, only FAT group preserved most of the gains in ROM (7-13%; p < 0.05). These results support the use of the newly developed IASMT, Fascial Abrasion Technique ™ and FR for increasing lower extremity ROM of athletes.

  20. Two Different Protocols for Knee Joint Motion Analyses in the Stance Phase of Gait: Correlation of the Rigid Marker Set and the Point Cluster Technique

    Takashi Fukaya

    2012-01-01

    Full Text Available Objective. There are no reports comparing the protocols provided by rigid marker set (RMS and point cluster technique (PCT, which are similar in terms of estimating anatomical landmarks based on markers attached to a segment. The purpose of this study was to clarify the correlation of the two different protocols, which are protocols for knee motion in gait, and identify whether measurement errors arose at particular periods during the stance phase. Methods. The study subjects were 10 healthy adults. All estimated anatomical landmarks were which their positions, calculated by each protocol of the PCT and RMS, were compared using Pearson’s product correlation coefficients. To examine the reliability of the angle changes of the knee joint measured by RMS and the PCT, the coefficient of multiple correlations (CMCs was used. Results. Although the estimates of the anatomical landmarks showed high correlations of >0.90 (<0.01 for the Y- and Z-coordinates, the correlations were low for the X-coordinates at all anatomical landmarks. The CMC was 0.94 for flexion/extension, 0.74 for abduction/adduction, and 0.71 for external/internal rotation. Conclusion. Flexion/extension and abduction/adduction of the knee by two different protocols had comparatively little error and good reliability after 30% of the stance phase.

  1. Dynamic contact mechanics on the tibial plateau of the human knee during activities of daily living.

    Gilbert, Susannah; Chen, Tony; Hutchinson, Ian D; Choi, Dan; Voigt, Clifford; Warren, Russell F; Maher, Suzanne A

    2014-06-27

    Despite significant advances in scaffold design, manufacture, and development, it remains unclear what forces these scaffolds must withstand when implanted into the heavily loaded environment of the knee joint. The objective of this study was to fully quantify the dynamic contact mechanics across the tibial plateau of the human knee joint during gait and stair climbing. Our model consisted of a modified Stanmore knee simulator (to apply multi-directional dynamic forces), a two-camera motion capture system (to record joint kinematics), an electronic sensor (to record contact stresses on the tibial plateau), and a suite of post-processing algorithms. During gait, peak contact stresses on the medial plateau occurred in areas of cartilage-cartilage contact; while during stair climb, peak contact stresses were located in the posterior aspect of the plateau, under the meniscus. On the lateral plateau, during gait and in early stair-climb, peak contact stresses occurred under the meniscus, while in late stair-climb, peak contact stresses were experienced in the zone of cartilage-cartilage contact. At 45% of the gait cycle, and 20% and 48% of the stair-climb cycle, peak stresses were simultaneously experienced on both the medial and lateral compartment, suggesting that these phases of loading warrant particular consideration in any simulation intended to evaluate scaffold performance. Our study suggests that in order to design a scaffold capable of restoring 'normal' contact mechanics to the injured knees, the mechanics of the intended site of implantation should be taken into account in any pre-clinical testing regime.

  2. Image-based compensation for involuntary motion in weight-bearing C-arm cone-beam CT scanning of knees

    Unberath, Mathias; Choi, Jang-Hwan; Berger, Martin; Maier, Andreas; Fahrig, Rebecca

    2015-03-01

    We previously introduced four fiducial marker-based strategies to compensate for involuntary knee-joint motion during weight-bearing C-arm CT scanning of the lower body. 2D methods showed significant reduction of motion- related artifacts, but 3D methods worked best. However, previous methods led to increased examination times and patient discomfort caused by the marker attachment process. Moreover, sub-optimal marker placement may lead to decreased marker detectability and therefore unstable motion estimates. In order to reduce overall patient discomfort, we developed a new image-based 2D projection shifting method. A C-arm cone-beam CT system was used to acquire projection images of five healthy volunteers at various flexion angles. Projection matrices for the horizontal scanning trajectory were calibrated using the Siemens standard PDS-2 phantom. The initial reconstruction was forward projected using maximum-intensity projections (MIP), yielding an estimate of a static scan. This estimate was then used to obtain the 2D projection shifts via registration. For the scan with the most motion, the proposed method reproduced the marker-based results with a mean error of 2.90 mm +/- 1.43 mm (compared to a mean error of 4.10 mm +/- 3.03 mm in the uncorrected case). Bone contour surrounding modeling clay layer was improved. The proposed method is a first step towards automatic image-based, marker-free motion-compensation.

  3. Voluntary activation of human knee extensors measured using transcranial magnetic stimulation.

    Goodall, S; Romer, L M; Ross, E Z

    2009-09-01

    The aim of this study was to determine the applicability and reliability of a transcranial magnetic stimulation twitch interpolation technique for measuring voluntary activation of a lower limb muscle group. Cortical voluntary activation of the knee extensors was determined in nine healthy men on two separate visits by measuring superimposed twitch torques evoked by transcranial magnetic stimulation during isometric knee extensions of varying intensity. Superimposed twitch amplitude decreased linearly with increasing voluntary torque between 50 and 100% of mean maximal torque, allowing estimation of resting twitch amplitude and subsequent calculation of voluntary activation. There were no systematic differences for maximal voluntary activation within day (mean +/- s.d. 90.9 +/- 6.2 versus 90.7 +/- 5.9%; P = 0.98) or between days (90.8 +/- 6.0 versus 91.2 +/- 5.7%; P = 0.92). Systematic bias and random error components of the 95% limits of agreement were 0.23 and 9.3% within day versus 0.38 and 7.5% between days. Voluntary activation was also determined immediately after a 2 min maximal voluntary isometric contraction; in four of these subjects, voluntary activation was determined 30 min after the sustained contraction. Immediately after the sustained isometric contraction, maximal voluntary activation was reduced from 91.2 +/- 5.7 to 74.2 +/- 12.0% (P knee extensors.

  4. MUSCLE ACTIVITY RESPONSE TO EXTERNAL MOMENT DURING SINGLE-LEG DROP LANDING IN YOUNG BASKETBALL PLAYERS: THE IMPORTANCE OF BICEPS FEMORIS IN REDUCING INTERNAL ROTATION OF KNEE DURING LANDING

    Meguru Fujii

    2012-06-01

    Full Text Available Internal tibial rotation with the knee close to full extension combined with valgus collapse during drop landing generally results in non-contact anterior cruciate ligament (ACL injury. The purpose of this study was to investigate the relationship between internal rotation of the knee and muscle activity from internal and external rotator muscles, and between the internal rotation of knee and externally applied loads on the knee during landing in collegiate basketball players. Our hypothesis was that the activity of biceps femoris muscle would be an important factor reducing internal knee rotation during landing. The subjects were 10 collegiate basketball students: 5 females and 5 males. The subjects performed a single-leg drop landing from a 25-cm height. Femoral and tibial kinematics were measured using a 3D optoelectronic tracking system during the drop landings, and then the knee angular motions were determined. Ground reaction forces and muscle activation patterns (lateral hamstring and medial hamstring were simultaneously measured and computed. Results indicated that lower peak internal tibial rotation angle at the time of landing was associated with greater lateral hamstring activity (r = -0.623, p < 0.001. When gender was considered, the statistically significant correlation remained only in females. There was no association between the peak internal tibial rotation angle and the knee internal rotation moment. Control of muscle activity in the lateral to medial hamstring would be an important factor in generating sufficient force to inhibit excessive internal rotation during landing. Strengthening the biceps femoris might mitigate the higher incidence of non-contact ACL injury in female athletes

  5. The effects of agonist and antagonist muscle activation on the knee extension moment-angle relationship in adults and children.

    O'Brien, Thomas D; Reeves, Neil D; Baltzopoulos, Vasilios; Jones, David A; Maganaris, Constantinos N

    2009-08-01

    The present study examined the effect of agonist activation and antagonist co-activation on the shape of the knee extension moment-angle relationship in adults and children. Isometric knee extension maximum voluntary contractions (MVCs) were performed at every 5 degrees of knee flexion between 55 degrees and 90 degrees (full extension = 0 degrees) by ten men, ten women, ten boys and ten girls. For each trial, the knee extensors' voluntary activation level was quantified using magnetic stimulation and the level of antagonist co-activation was quantified from their electromyographical activity. Peak MVC moment was greater for men (264 +/- 63 N m) than women (177 +/- 60 N m), and greater for adults than children (boys 78 +/- 17 N m, girls 91 +/- 28 N m) (p architecture, and the pattern of the moment arm-angle relationship may in combination occur so that as children develop and mature into adults the shape of the moment-angle relationship is not altered.

  6. Sustained Rhythmic Brain Activity Underlies Visual Motion Perception in Zebrafish

    Verónica Pérez-Schuster

    2016-10-01

    Full Text Available Following moving visual stimuli (conditioning stimuli, CS, many organisms perceive, in the absence of physical stimuli, illusory motion in the opposite direction. This phenomenon is known as the motion aftereffect (MAE. Here, we use MAE as a tool to study the neuronal basis of visual motion perception in zebrafish larvae. Using zebrafish eye movements as an indicator of visual motion perception, we find that larvae perceive MAE. Blocking eye movements using optogenetics during CS presentation did not affect MAE, but tectal ablation significantly weakened it. Using two-photon calcium imaging of behaving GCaMP3 larvae, we find post-stimulation sustained rhythmic activity among direction-selective tectal neurons associated with the perception of MAE. In addition, tectal neurons tuned to the CS direction habituated, but neurons in the retina did not. Finally, a model based on competition between direction-selective neurons reproduced MAE, suggesting a neuronal circuit capable of generating perception of visual motion.

  7. Cross-cultural validity of the animated activity questionnaire (AAQ) that assesses activity limitations in patients with hip or knee osteoarthritis

    Peter, W. F.; De Vet, R.; Boers, M.

    2015-01-01

    Background: The Animated Activity Questionnaire (AAQ) measures activity limitations in hip and knee osteoarthritis (HKOA), and demonstrated good validity and reliability [1]. The AAQ shows stylized video animations of different levels of activity performance. Patients are asked to choose which...

  8. 高空运动落地后对膝盖的冲击力学分析%Analysis of Knee Motion Force Parameters After Air Sport Landfall

    孙斌

    2015-01-01

    传统方法构建的高空运动落体后对膝盖的冲击力学分析模型只能求解局部的膝关节受力和发力参数,对膝盖及下肢的各个关节驱动作用和受力冲击运动势能等参数求解建模困难.提出一种基于七连杆驱动结构的高空运动落体后的冲击动力学分析模型.构建人体在高空落地后的下肢膝盖的运动链数学模型,分析落地冲击对膝盖的运动链位姿变换关系,采用7连杆驱动结构对人体高空落地后的下肢进行7连杆结构分解,采用Lagrange动力学方程实现对冲击力学参数的全局分析,得出优化解向量.仿真结果表明,采用该受力分析模型,对膝盖冲击力的受力分析逼近于理论值,计算精度较高,性能优越,为体育训练和运动医疗提供准确的数据基础.%The impact of knee mechanics analysis model of high altitude exercise fall, driving torque and dynamic parame-ters of human lower limb joints, provides the model and the data base for the guidance of scientific sports training and sports medicine. Impact mechanics of knee motion analysis of high altitude falling after the traditional method of the knee joint model can solve the local force and force parameters of each joint, knee and lower limb function and the driving force of impact energy parameters modeling difficulty movement. An analysis model of driving air sports fall based on the struc-ture of the seven link rear impact dynamics is proposed. Construction at high altitude after landing leg knee motion of hu-man body even mathematical model, analysis the impact of the kinematic chain knee pose transformation relations, the 7 connecting rod to drive the structure of the human body at high altitude after the fall of the lower limb was decomposed 7 connecting rod structure, the dynamic equation of Lagrange to achieve the overall impact of mechanical parameters analy-sis, obtains the optimization solution vector. Simulation results show that the stress

  9. Abdominal muscle activation changes if the purpose is to control pelvis motion or thorax motion.

    Vera-Garcia, Francisco J; Moreside, Janice M; McGill, Stuart M

    2011-12-01

    The aim of this study was to compare trunk muscular recruitment and lumbar spine kinematics when motion was constrained to either the thorax or the pelvis. Nine healthy women performed four upright standing planar movements (rotations, anterior-posterior translations, medial-lateral translations, and horizontal circles) while constraining pelvis motion and moving the thorax or moving the pelvis while minimizing thorax motion, and four isometric trunk exercises (conventional curl-up, reverse curl-up, cross curl-up, and reverse cross curl-up). Surface EMG (upper and lower rectus abdominis, lateral and medial aspects of external oblique, internal oblique, and latissimus dorsi) and 3D lumbar displacements were recorded. Pelvis movements produced higher EMG amplitudes of the oblique abdominals than thorax motions in most trials, and larger lumbar displacements in the medial-lateral translations and horizontal circles. Conversely, thorax movements produced larger rotational lumbar displacement than pelvis motions during rotations and higher EMG amplitudes for latissimus dorsi during rotations and anterior-posterior translations and for lower rectus abdominis during the crossed curl-ups. Thus, different neuromuscular compartments appear when the objective changes from pelvis to thorax motion. This would suggest that both movement patterns should be considered when planning spine stabilization programs, to optimize exercises for the movement and muscle activations desired.

  10. Assessment of Knee Cartilage Stress Distribution and Deformation Using Motion Capture System and Wearable Sensors for Force Ratio Detection

    N. Mijailovic

    2015-01-01

    Full Text Available Knowledge about the knee cartilage deformation ratio as well as the knee cartilage stress distribution is of particular importance in clinical studies due to the fact that these represent some of the basic indicators of cartilage state and that they also provide information about joint cartilage wear so medical doctors can predict when it is necessary to perform surgery on a patient. In this research, we apply various kinds of sensors such as a system of infrared cameras and reflective markers, three-axis accelerometer, and force plate. The fluorescent marker and accelerometers are placed on the patient’s hip, knee, and ankle, respectively. During a normal walk we are recording the space position of markers, acceleration, and ground reaction force by force plate. Measured data are included in the biomechanical model of the knee joint. Geometry for this model is defined from CT images. This model includes the impact of ground reaction forces, contact force between femur and tibia, patient body weight, ligaments, and muscle forces. The boundary conditions are created for the finite element method in order to noninvasively determine the cartilage stress distribution.

  11. Strength Training to Contraction Failure Increases Voluntary Activation of the Quadriceps Muscle Shortly After Total Knee Arthroplasty

    Mikkelsen, Elin Karin; Jakobsen, Thomas Linding; Holsgaard-Larsen, Anders;

    2016-01-01

    OBJECTIVE: The objective of this study was to investigate voluntary activation of the quadriceps muscle during one set of knee extensions performed until contraction failure in patients shortly after total knee arthroplasty. DESIGN: This was a cross-sectional study of 24 patients with total knee...... arthroplasty. One set of knee extensions was performed until contraction failure, using a predetermined 10 repetition maximum loading. In the operated leg, electromyographic (EMG) activity of the lateral and medial vastus, semitendinosus, and biceps femoris muscles was recorded during the set. Muscle activity...... (%EMGmax) and median power frequency of the EMG power spectrum were calculated for each repetition decile (10%-100% contraction failure). RESULTS: Muscle activity increased significantly over contractions from a mean of 90.0 and 93.6 %EMGmax (lateral vastus and medial vastus, respectively) at 10...

  12. Comorbidity, limitations in activities and pain in patients with osteoarthritis of the hip or knee

    Arwert Henk

    2008-06-01

    Full Text Available Abstract Background This study aims to contribute to the knowledge of the influence of comorbidity in OA. The objectives of the study were (i to describe the prevalence of comorbidity and (ii to describe the relationship between comorbidity (morbidity count, severity and the presence of specific diseases and limitations in activities and pain in elderly patients with knee or hip OA using a comprehensive inventory of comorbidity. Methods A cross-sectional cohort study was conducted, in which 288 elderly patients with hip or knee osteoarthritis were included. Apart from demographic and clinical data, information about comorbidity, limitations in activities (WOMAC, SF-36 and timed walking test and pain (VAS was collected by questionnaires and tests. Statistical analyses included descriptive statistics, multivariate regression techniques, t-tests and one-way ANOVA. Results Almost all patients suffered from at least one comorbid disease, with cardiac diseases, diseases of eye, ear, nose, throat and larynx, other urogenital diseases and endocrine/metabolic diseases being most prevalent. Morbidity count and severity index were associated with more limitations in activities and with more pain. The presence of most of the moderate or severe diseases and obesity was associated with limitations in activities or with pain. Conclusion The results of this study emphasize the importance of comorbidity in the rehabilitation of elderly patients with osteoarthritis of the hip or knee. Clinical practitioners should be aware of the relationship of comorbidity with functional problems in OA patients.

  13. Comorbidity, limitations in activities and pain in patients with osteoarthritis of the hip or knee

    van Dijk, Gabriella M; Veenhof, Cindy; Schellevis, Francois; Hulsmans, Harry; Bakker, Jan PJ; Arwert, Henk; Dekker, Jos HM; Lankhorst, Guus J; Dekker, Joost

    2008-01-01

    Background This study aims to contribute to the knowledge of the influence of comorbidity in OA. The objectives of the study were (i) to describe the prevalence of comorbidity and (ii) to describe the relationship between comorbidity (morbidity count, severity and the presence of specific diseases) and limitations in activities and pain in elderly patients with knee or hip OA using a comprehensive inventory of comorbidity. Methods A cross-sectional cohort study was conducted, in which 288 elderly patients with hip or knee osteoarthritis were included. Apart from demographic and clinical data, information about comorbidity, limitations in activities (WOMAC, SF-36 and timed walking test) and pain (VAS) was collected by questionnaires and tests. Statistical analyses included descriptive statistics, multivariate regression techniques, t-tests and one-way ANOVA. Results Almost all patients suffered from at least one comorbid disease, with cardiac diseases, diseases of eye, ear, nose, throat and larynx, other urogenital diseases and endocrine/metabolic diseases being most prevalent. Morbidity count and severity index were associated with more limitations in activities and with more pain. The presence of most of the moderate or severe diseases and obesity was associated with limitations in activities or with pain. Conclusion The results of this study emphasize the importance of comorbidity in the rehabilitation of elderly patients with osteoarthritis of the hip or knee. Clinical practitioners should be aware of the relationship of comorbidity with functional problems in OA patients. PMID:18582362

  14. Technology Efficacy in Active Prosthetic Knees for Transfemoral Amputees: A Quantitative Evaluation

    Amr M. El-Sayed

    2014-01-01

    Full Text Available Several studies have presented technological ensembles of active knee systems for transfemoral prosthesis. Other studies have examined the amputees’ gait performance while wearing a specific active prosthesis. This paper combined both insights, that is, a technical examination of the components used, with an evaluation of how these improved the gait of respective users. This study aims to offer a quantitative understanding of the potential enhancement derived from strategic integration of core elements in developing an effective device. The study systematically discussed the current technology in active transfemoral prosthesis with respect to its functional walking performance amongst above-knee amputee users, to evaluate the system’s efficacy in producing close-to-normal user performance. The performances of its actuator, sensory system, and control technique that are incorporated in each reported system were evaluated separately and numerical comparisons were conducted based on the percentage of amputees’ gait deviation from normal gait profile points. The results identified particular components that contributed closest to normal gait parameters. However, the conclusion is limitedly extendable due to the small number of studies. Thus, more clinical validation of the active prosthetic knee technology is needed to better understand the extent of contribution of each component to the most functional development.

  15. Knee hemarthrosis after arthroscopic surgery in an athlete with low factor XIII activity

    Tsujii Akira; Tanaka Yoshinari; Yonetani Yasukazu; Shiozaki Yoshiki; Tomiyama Yoshiaki; Horibe Shuji

    2012-01-01

    Abstract We report a thirteen-year-old tennis player with knee hemarthrosis caused by low factor XIII activity. She visited our hospital because of medial peripatellar pain for two years. Although there was no abnormal sign in X-ray or MRI, diagnostic arthroscopy was performed. It revealed some cartilage debris, medial plica and complete septum of suprapatellar plica. Removing the debris by washing out and resecting the medial plica, she could return to play tennis without perioperative sympt...

  16. Video summarization using descriptors of motion activity: a motion activity based approach to key-frame extraction from video shots

    Divakaran, Ajay; Radhakrishnan, Regunathan; Peker, Kadir A.

    2001-10-01

    We describe a video summarization technique that uses motion descriptors computed in the compressed domain. It can either speed up conventional color-based video summarization techniques, or rapidly generate a key-frame based summary by itself. The basic hypothesis of the work is that the intensity of motion activity of a video segment is a direct indication of its `summarizability,' which we experimentally verify using the MPEG-7 motion activity descriptor and the fidelity measure proposed in H. S. Chang, S. Sull, and S. U. Lee, `Efficient video indexing scheme for content-based retrieval,' IEEE Trans. Circuits Syst. Video Technol. 9(8), (1999). Note that the compressed domain extraction of motion activity intensity is much simpler than the color-based calculations. We are thus able to quickly identify easy to summarize segments of a video sequence since they have a low intensity of motion activity. We are able to easily summarize these segments by simply choosing their first frames. We can then apply conventional color-based summarization techniques to the remaining segments. We thus speed up color-based summarization by reducing the number of segments processed. Our results also motivate a simple and novel key-frame extraction technique that relies on a motion activity based nonuniform sampling of the frames. Our results indicate that it can either be used by itself or to speed up color-based techniques as explained earlier.

  17. A conceptual framework for a sports knee injury performance profile (SKIPP and return to activity criteria (RTAC

    David Logerstedt

    2015-10-01

    Full Text Available ABSTRACTInjuries to the knee, including intra-articular fractures, ligamentous ruptures, and meniscal and articular cartilage lesions, are commonplace within sports. Despite advancements in surgical techniques and enhanced rehabilitation, athletes returning to cutting, pivoting, and jumping sports after a knee injury are at greater risk of sustaining a second injury. The clinical utility of objective criteria presents a decision-making challenge to ensure athletes are fully rehabilitated and safe to return to sport. A system centered on specific indicators that can be used to develop a comprehensive profile to monitor rehabilitation progression and to establish return to activity criteria is recommended to clear athletes to begin a progressive and systematic approach to activities and sports. Integration of a sports knee injury performance profile with return to activity criteria can guide clinicians in facilitating an athlete's safe return to sport, prevention of subsequent injury, and life-long knee joint health.

  18. A conceptual framework for a sports knee injury performance profile (SKIPP) and return to activity criteria (RTAC)

    Logerstedt, David; Arundale, Amelia; Lynch, Andrew; Snyder-Mackler, Lynn

    2015-01-01

    Injuries to the knee, including intra-articular fractures, ligamentous ruptures, and meniscal and articular cartilage lesions, are commonplace within sports. Despite advancements in surgical techniques and enhanced rehabilitation, athletes returning to cutting, pivoting, and jumping sports after a knee injury are at greater risk of sustaining a second injury. The clinical utility of objective criteria presents a decision-making challenge to ensure athletes are fully rehabilitated and safe to return to sport. A system centered on specific indicators that can be used to develop a comprehensive profile to monitor rehabilitation progression and to establish return to activity criteria is recommended to clear athletes to begin a progressive and systematic approach to activities and sports. Integration of a sports knee injury performance profile with return to activity criteria can guide clinicians in facilitating an athlete's safe return to sport, prevention of subsequent injury, and life-long knee joint health. PMID:26537805

  19. Knee Replacement

    Knee replacement is surgery for people with severe knee damage. Knee replacement can relieve pain and allow you to ... Your doctor may recommend it if you have knee pain and medicine and other treatments are not ...

  20. Fiducial marker-based correction for involuntary motion in weight-bearing C-arm CT scanning of knees. II. Experiment

    Choi, Jang-Hwan [Department of Radiology, Stanford University, Stanford, California 94305 and Department of Mechanical Engineering, Stanford University, Stanford, California 94305 (United States); Maier, Andreas; Keil, Andreas; McWalter, Emily J.; Gold, Garry E.; Fahrig, Rebecca [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Pal, Saikat [Biomedical Engineering Department, California Polytechnic State University, San Luis Obispo, California 93407 (United States); Beaupré, Gary S. [Musculoskeletal Research Laboratory, VA Palo Alto Health Care System, Palo Alto, California 94304 (United States)

    2014-06-15

    Purpose: A C-arm CT system has been shown to be capable of scanning a single cadaver leg under loaded conditions by virtue of its highly flexible acquisition trajectories. In Part I of this study, using the 4D XCAT-based numerical simulation, the authors predicted that the involuntary motion in the lower body of subjects in weight-bearing positions would seriously degrade image quality and the authors suggested three motion compensation methods by which the reconstructions could be corrected to provide diagnostic image quality. Here, the authors demonstrate that a flat-panel angiography system is appropriate for scanning both legs of subjectsin vivo under weight-bearing conditions and further evaluate the three motion-correction algorithms using in vivo data. Methods: The geometry of a C-arm CT system for a horizontal scan trajectory was calibrated using the PDS-2 phantom. The authors acquired images of two healthy volunteers while lying supine on a table, standing, and squatting at several knee flexion angles. In order to identify the involuntary motion of the lower body, nine 1-mm-diameter tantalum fiducial markers were attached around the knee. The static mean marker position in 3D, a reference for motion compensation, was estimated by back-projecting detected markers in multiple projections using calibrated projection matrices and identifying the intersection points in 3D of the back-projected rays. Motion was corrected using three different methods (described in detail previously): (1) 2D projection shifting, (2) 2D deformable projection warping, and (3) 3D rigid body warping. For quantitative image quality analysis, SSIM indices for the three methods were compared using the supine data as a ground truth. Results: A 2D Euclidean distance-based metric of subjects’ motion ranged from 0.85 mm (±0.49 mm) to 3.82 mm (±2.91 mm) (corresponding to 2.76 to 12.41 pixels) resulting in severe motion artifacts in 3D reconstructions. Shifting in 2D, 2D warping, and 3D

  1. Swing Phase Control of Semi-Active Prosthetic Knee Using Neural Network Predictive Control With Particle Swarm Optimization.

    Ekkachai, Kittipong; Nilkhamhang, Itthisek

    2016-11-01

    In recent years, intelligent prosthetic knees have been developed that enable amputees to walk as normally as possible when compared to healthy subjects. Although semi-active prosthetic knees utilizing magnetorheological (MR) dampers offer several advantages, they lack the ability to generate active force that is required during some states of a normal gait cycle. This prevents semi-active knees from achieving the same level of performance as active devices. In this work, a new control algorithm for a semi-active prosthetic knee during the swing phase is proposed to reduce this gap. The controller uses neural network predictive control and particle swarm optimization to calculate suitable command signals. Simulation results using a double pendulum model show that the generated knee trajectory of the proposed controller is more similar to the normal gait than previous open-loop controllers at various ambulation speeds. Moreover, the investigation shows that the algorithm can be calculated in real time by an embedded system, allowing for easy implementation on real prosthetic knees.

  2. Knee Angle Estimation Algorithm for Myoelectric Control of Active Transfemoral Prostheses

    Delis, Alberto López; de Carvalho, João Luiz Azevedo; Da Rocha, Adson Ferreira; de Oliveira Nascimento, Francisco Assis; Borges, Geovany Araújo

    This paper presents a bioinstrumentation system for the acquisition and pre-processing of surface electromyographic (SEMG) signals, and a knee angle estimation algorithm for control of active transfemoral leg prostheses, using methods for feature extraction and classification of myoelectric signal patterns. The presented microcontrolled bioinstrumentation system is capable of recording up to four SEMG channels, and one electrogoniometer channel. The proposed neural myoelectric controller algorithm is capable of predicting the intended knee joint angle from the measured SEMG signals. The algorithm is designed in three stages: feature extraction, using auto-regressive model and amplitude histogram; feature projection, using self organizing maps; and pattern classification, using a Levenberg-Marquardt neural network. The use of SEMG signals and additional mechanical information such as that provided by the electrogoniometer may improve precision in the control of leg prostheses. Preliminary results are presented.

  3. Does the GMFCS level influence the improvement in knee range of motion after rectus femoris transfer in cerebral palsy?

    Blumetti, Francesco C; Morais Filho, Mauro C; Kawamura, Cátia M; Cardoso, Michelle O; Neves, Daniella L; Fujino, Marcelo H; Lopes, José Augusto F

    2015-09-01

    The aim of this study was to evaluate the influence of the Gross Motor Function Classification System (GMFCS) on the outcomes of rectus femoris transfer (RFT) for patients with cerebral palsy and stiff knee gait. We performed a retrospective review of patients seen at our gait laboratory from 1996 to 2013. Inclusion criteria were (i) spastic diplegic cerebral palsy, (ii) GMFCS levels I-III, (iii) reduced peak knee flexion in swing (PKFSwGMFCS levels I and II. In the non-RFT group, no improvement in KROM was observed in any GMFCS level. In this study, patients at GMFCS levels I and II were more likely to benefit from the RFT procedure.

  4. Methods for dynamic characterization of the major muscles activating the lower limb joints in cycling motion

    Navit Roth

    2014-09-01

    Full Text Available The functional activation, through electrical stimulation, of the lower limb consisting of several deficient muscles requires well-patterned and coordinated activation of these muscles. This study presents a method for characterizing the parameters of the major muscle groups controlling the ankle and knee joints in cycling motion, the latter having particular significance in the rehabilitation of locomotion. To lower mechanical indeterminacy in the joints the system is reduced by grouping the muscles acting in synergism. The joint torques were calculated by inverse dynamics methods from cycling motion data, including kinematics and foot/pedal reaction loads (forces, moments. The mechanical indeterminacy was resolved by applying optimization criteria and the individual muscle torques were parceled-out from the joint torques. System identification of the individual muscles, part of which being bi-articular, in this non-isometric condition was performed from the relationship between the evaluated force and the measured EMG of each the muscles, using both first and second order linear transfer functions. Feasibility of the presented method was demonstrated through the computation of the coefficients of the muscles involved and validating the results on the experimental data obtained from one subject.

  5. The benefits and barriers to physical activity and lifestyle interventions for osteoarthritis affecting the adult knee

    Stevenson Jonathan

    2012-03-01

    Full Text Available Abstract Osteoarthritis prevalence is increasing, placing greater demands on healthcare and future socioeconomic costing models. Exercise and non-pharmacological methods should be employed to manage this common and disabling disease. Expectations at all stages of disease are increasing with a desire to remain active and independent. Three key areas have been reviewed; the evidence for physical activity, lifestyle changes and motivational techniques concerning knee osteoarthritis and the barriers to instituting such changes. Promotion of activity in primary care is discussed and evidence for compliance has been reviewed. This article reviews a subject that is integral to all professionals involved with osteoarthritis care.

  6. Functional outcomes of uni-knee arthroplasty for medial compartment knee arthropathy in asian patients

    To Wong

    2014-12-01

    Full Text Available Background: Uni-knee arthroplasty (UKA has shown better knee kinematics and motion that may better suit the activities of daily living in Eastern countries. The purpose of this study was to evaluate the functional outcomes of UKA for medial compartment knee arthropathy in Asian patients. Methods: The study cohort consisted of 48 patients with 51 UK A knees. Only one type of prosthesis was used and all components were cemented. Postoperative management included ambulation with weight bearing, range of motion, and muscle strengthening exercises as tolerated until full recovery. The average follow-up was 52.0 ± 24.0 (range 12-92 months. The evaluation included functional assessment, the Knee Society knee and functional scores, the International Knee Document Committee (IKDC subjective and objective scores, and radiographs of the knee. Results: The overall clinical outcomes of the knee showed the functional outcome of the knee to be normal in 51%, nearly normal in 37%, abnormal in 8%, and severely abnormal in 4%. The functional activities included stair climbing in 96%, squatting in 76%, jogging in 71% and kneeling in 47%. Three-quarters of the patients were able to kneel for daily activities. Approximately 98% of the patients were satisfied with the operation. The survivorship of the prosthesis was 98% with one revision pending. Radiographic evaluations revealed the components were centered in 82% and off-centered in 18%. Osteoarthritis was 22% preoperative and 27% postoperative for the patellofemoral compartment, and 0% before and 4% after surgery for the lateral compartment. The functional outcomes showed no difference between patients with and without patellofemoral arthritis. The complications included one component malposition and one knee pain of undetermined origin. Conclusions: UKA provides excellent pain relief and restoration of knee function including kneeling, squatting, and sit-to-stand activities that perfectly fit the oriental

  7. Cooling does not affect knee proprioception.

    Ozmun, J C; Thieme, H A; Ingersoll, C D; Knight, K L

    1996-01-01

    The effect of cooling on proprioception of the knee has not been studied extensively. In this study, we investigated the movement reproduction (timing and accuracy) aspect of proprioception. Subjects were tested under two conditions: a 20-minute application of ice and control. Proprioceptive accuracy and timing were measured by passively moving the knee, then comparing the subject's active reproduction of the passive movement. Subjects were blindfolded, then tested in three sectors of the knee's range of motion: 90 degrees to 60 degrees , 60 degrees to 30 degrees , and 30 degrees to full extension. Ice application had no apparent effect on the subject's ability to perform accurate movement reproductions in the sectors tested. However, accuracy of the subject's final angle reproduction varied between the sectors as did the total time of the movement. One possible explanation for the difference between sectors is that different receptors are active at different points in the knee's range of motion. We conclude that cooling the knee joint for 20 minutes does not have an adverse effect on proprioception.

  8. Companion classroom activities for "stop faking it!" force and motion

    Robertson, William C

    2011-01-01

    Never has it been so easy for educators to learn to teach physical science with confidence. Award-winning author Bill Robertson launched his bestselling Stop Faking It! series in 2002 with Force and Motion--offering elementary and middle school teachers a jargon-free way to learn the background for teaching physical science with confidence. Combining easy-to-understand if irreverent explanations and quirky diagrams, Stop Faking It! Force and Motion helped thousands of teachers, parents, and homeschoolers conquer topics from Newton s laws to the physics of space travel. Now Companion Classroom Activities for Stop Faking It! Force and Motion proves an ideal supplement to the original book or a valuable resource of its own. The hands-on activities and highly readable explanations allow students to first investigate concepts, then discuss learned concepts, and finally apply the concepts to everyday situations. Robertson's wit and humor are sure to keep students and teachers entertained while they tackle topics ...

  9. In vivo prompt gamma neutron activation analysis for the screening of boron-10 distribution in a rabbit knee: a simulation study

    Zhu, X.; Clackdoyle, R.; Shortkroff, S.; Yanch, J.

    2008-05-01

    Boron neutron capture synovectomy (BNCS) is under development as a potential treatment modality for rheumatoid arthritis (RA). RA is characterized by the inflammation of the synovium (the membrane lining articular joints), which leads to pain and a restricted range of motion. BNCS is a two-part procedure involving the injection of a boronated compound directly into the diseased joint followed by irradiation with a low-energy neutron beam. The neutron capture reactions taking place in the synovium deliver a local, high-linear energy transfer (LET) dose aimed at destroying the inflamed synovial membrane. For successful treatment via BNCS, a boron-labeled compound exhibiting both high synovial uptake and long retention time is necessary. Currently, the in vivo uptake behavior of potentially useful boronated compounds is evaluated in the knee joints of rabbits in which arthritis has been induced. This strategy involves the sacrifice and dissection of a large number of animals. An in vivo 10B screening approach is therefore under investigation with the goal of significantly reducing the number of animals needed for compound evaluation via dissection studies. The 'in vivo prompt gamma neutron activation analysis' (IVPGNAA) approach uses a narrow neutron beam to irradiate the knee from several angular positions following the intra-articular injection of a boronated compound whose uptake characteristics are unknown. A high-purity germanium detector collects the 478 keV gamma photons produced by the 10B capture reactions. The 10B distribution in the knee is then reconstructed by solving a system of simultaneous equations using a weighted least squares algorithm. To study the practical feasibility of IVPGNAA, simulation data were generated with the Monte Carlo N-particle transport code. The boron-containing region of a rabbit knee was partitioned into 8 compartments, and the 10B prompt gamma signals were tallied from 16 angular positions. Results demonstrate that for this

  10. Total knee arthroplasty for knee varus deformity:follow-up evaluation of femorotibial angle and range of motion%全膝关节置换修复膝内翻畸形:胫股角及膝关节活动度随访评价

    李广伟; 王红军; 孙晓智; 陈林斌; 高宇亮; 白忠旭; 程新胜

    2015-01-01

      结果与结论:所有患者均获得随访,随访时间为12-96个月,随访方式为门诊复查随访。胫股角由置换前平均内翻17.69°(5°-30°)纠正至置换后的5.66°(2°-8°),膝关节活动度由置换前的74.29°(60°-95°)提高到置换后119.46°(105°-130°);HSS评分由置换前的26.60分(14-42分)提高到置换后89.03分(82-95分),优28膝,良7膝;WOMAC评分由42.83分(28-54分)提高到置换后90.17分(85-95分)。结果经统计学分析提示,所有病例置换后胫股角、膝关节活动度、HSS及WOMAC评分均较置换前显著改善(P OBJECTIVE:To observe the femorotibial angle and range of knee joint motion of adults patients with knee varus deformity during 1-year fol ow-up after total knee arthroplasty. METHODS:A total of 31 patients (35 knees) with knee varus deformity were treated with posterior stabilized prosthesis replacement from June 2006 to June 2013. Using patel ar medial approach, the correct osteotomy and selective soft tissue release were performed to restore normal knee alignment and soft tissue balance. Posterior stabilized prosthesis in total knee arthroplasty was applied to achieve knee stability. Postoperative targeted rehabilitation training was also fol owed. The femorotibial angle was measured before and after surgery. The range of knee joint motion was determined during postoperative fol ow-up. Patients were evaluated with the Hospital for Special Surgery (HSS) score and the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. RESULTS AND CONCLUSION:Al patients were fol owed up for 12-96 months through out-patient clinic. The femorotibial angle was corrected from preoperative varus 17.69° (5°-30°) to postoperative 5.66° (2°-8°);the range of knee joint motion was improved from preoperative 74.29° (60°-95°) to 119.46° (105°-130°);the HSS score increased from preoperative 26.60 points (14-42 points) to postoperative 89.03 points (82-95 points

  11. Intra-articular morphine versus bupivacaine for knee motion among patients with osteoarthritis: randomized double-blind clinical trial

    Miriam Bellini Gazi

    Full Text Available CONTEXT AND OBJECTIVE: Osteoarthritis causes pain and disability in a high percentage of elderly people. The aim of the present study was to assess the efficacy of intra-articular morphine and bupivacaine on the joint flexion and extension angles of patients with knee osteoarthritis. DESIGN AND SETTING: A randomized double-blind study was performed at a pain clinic of Universidade Federal de São Paulo. METHODS: Thirty-nine patients with pain for more than three months, of intensity greater than three on a numerical scale (zero to 10, were included. G1 patients received 1 mg (1 ml of morphine diluted in 9 ml of saline, intra-articularly, and G2 patients received 25 mg (10 ml of 0.25% bupivacaine without epinephrine. Pain was assessed on a numerical scale and knee flexion and extension angles were measured after administration of the drugs at rest and during movement. The total amount of analgesic supplementation using 500 mg doses of paracetamol was also determined. RESULTS: No significant difference in pain intensity was observed between G1 and G2. Significant decreases in pain at rest and during movement and significant increases in mean flexion and extension angles were observed in both groups, with no significant difference between the two groups. The mean total amount of paracetamol used over a seven-day period was 3578 mg in G1 and 5333 mg in G2 (P = 0.2355; Mann-Whitney test. CONCLUSION: The analgesic effects of 1 mg of morphine and 25 mg of 0.25% bupivacaine were similar among patients with osteoarthritis of the knee.

  12. A study on muscle activity and ratio of the knee extensor depending on the types of squat exercise

    Kang, Jeong-Il; Park, Joon-Su; Choi, Hyun; Jeong, Dae-Keun; Kwon, Hye-Min; Moon, Young-Jun

    2017-01-01

    [Purpose] For preventing the patellofemoral pain syndrome, this study aims to suggest a proper squat method, which presents selective muscle activity of Vastus Medialis Oblique and muscle activity ratios of Vastus Medialis Oblique/Vastus Lateralis by applying squat that is a representative weight bearing exercise method in various ways depending on the surface conditions and knee bending angles. [Subjects and Methods] An isometric squat that was accompanied by hip adduction, depending on the surface condition and the knee joint flexion angle, was performed by 24 healthy students. The muscle activity and the ratio of muscle activity were measured. [Results] In a comparison of muscle activity depending on the knee joint flexion angle on a weight-bearing surface, the vastus medialis oblique showed a significant difference at 15° and 60°. Meanwhile, in a comparison of the muscle activity ratio between the vastus medialis oblique and the vastus lateralis depending on the knee joint flexion angle on a weight-bearing surface, significant differences were observed at 15° and 60°. [Conclusion] An efficient squat exercise posture for preventing the patellofemoral pain syndrome is to increase the knee joint bending angle on a stable surface. But it would be efficient for patients with difficulties in bending the knee joint to keep a knee joint bending angle of 15 degrees or less on an unstable surface. It is considered that in future, diverse studies on selective Vastus Medialis Oblique strengthening exercise methods would be needed after applying them to patients with the patellofemoral pain syndrome. PMID:28210036

  13. Statistics of Superluminal Motion in Active Galactic Nuclei

    Yong-Wei Zhang; Jun-Hui Fan

    2008-01-01

    We have collected an up-to-date sample of 123 superluminal sources (84 quasars, 27 BL Lac objects and 12 galaxies) and calculated the apparent velocities (βapp) for 224 components in the sources with the A-CDM model. We checked the relationships between their proper motions, redshifts,βapp and 5 GHz flux densities. Our analysis shows that the radio emission is strongly boosted by the Doppler effect. The superluminal motion and the relativistic beaming boosting effect are, to some extent, the same in active galactic nuclei.

  14. H.264 MOTION ESTIMATION ALGORITHM BASED ON VIDEO SEQUENCES ACTIVITY

    2008-01-01

    Motion estimation is an important part of H.264/AVC encoding progress, with high computational complexity. Therefore, it is quite necessary to find a fast motion estimation algorithm for real-time applications. The algorithm proposed in this letter adjudges the macroblocks activity degree first; then classifies different video sequences, and applies different search strategies according to the result. Experiments show that this method obtains almost the same video quality with the Full Search (FS) algorithm but with reduced more than 95% computation cost.

  15. Influence of knee flexion angle and age on triceps surae muscle activity during heel raises.

    Hébert-Losier, Kim; Schneiders, Anthony G; García, José A; Sullivan, S John; Simoneau, Guy G

    2012-11-01

    Triceps surae and Achilles tendon injuries are frequent in sports medicine, particularly in middle-aged adults. Muscle imbalances and weakness are suggested to be involved in the etiology of these conditions, with heel-raise testing often used to assess and treat triceps surae (TS) injuries. Although heel raises are recommended with the knee straight for gastrocnemius and bent for soleus (SOL), the extent of muscle selectivity in these positions is not clear. This study aimed to determine the influence of knee angle and age on TS muscle activity during heel raises. Forty-eight healthy men and women were recruited from a younger-aged (18-25 years) and middle-aged (35-45 years) population. All the subjects performed unilateral heel raises in 0° and 45° knee flexion (KF). Soleus, gastrocnemius medialis (GM) and gastrocnemius lateralis (GL) surface electromyography signals were processed to compute root-mean-square amplitudes, and data were analyzed using mixed-effects models and stepwise regression. The mean TS activity during heel raises was 23% of maximum voluntary isometric contraction when performed in 0° KF and 21% when in 45°. Amplitudes were significantly different between TS muscles (p < 0.001) and KF angles (p < 0.001), with a significant interaction (p < 0.001). However, the age of the population did not influence the results (p = 0.193). The findings demonstrate that SOL activity was 4% greater when tested in 45° compared with 0° KF and 5% lower in the GM and GL. The results are consistent with the recommended use of heel raises in select knee positions for assessing, training, and rehabilitating the SOL and gastrocnemius muscles; however, the 4-5% documented change in activity might not be enough to significantly influence clinical outcome measures or muscle-specific benefits. Contrary to expectations, TS activity did not distinguish between middle-aged and younger-aged adults, despite the higher injury prevalence in middle age.

  16. An acute bout of self-myofascial release increases range of motion without a subsequent decrease in muscle activation or force.

    MacDonald, Graham Z; Penney, Michael D H; Mullaley, Michelle E; Cuconato, Amanda L; Drake, Corey D J; Behm, David G; Button, Duane C

    2013-03-01

    Foam rolling is thought to improve muscular function, performance, overuse, and joint range of motion (ROM); however, there is no empirical evidence demonstrating this. Thus, the objective of the study was to determine the effect of self-myofascial release (SMR) via foam roller application on knee extensor force and activation and knee joint ROM. Eleven healthy male (height 178.9 ± 3.5 cm, mass 86.3 ± 7.4 kg, age 22.3 ± 3.8 years) subjects who were physically active participated. Subjects' quadriceps maximum voluntary contraction force, evoked force and activation, and knee joint ROM were measured before, 2 minutes, and 10 minutes after 2 conditions: (a) 2, 1-minute trials of SMR of the quadriceps via a foam roller and (b) no SMR (Control). A 2-way analysis of variance (condition × time) with repeated measures was performed on all dependent variables recorded in the precondition and postcondition tests. There were no significant differences between conditions for any of the neuromuscular dependent variables. However, after foam rolling, subjects' ROM significantly (p foam rolling, which no longer existed after foam rolling. In conclusion, an acute bout of SMR of the quadriceps was an effective treatment to acutely enhance knee joint ROM without a concomitant deficit in muscle performance.

  17. 全膝关节置换治疗成人膝外翻畸形:胫股角及膝关节活动度变化%Total knee arthroplasty for knee valgus deformity in the adults: Changes of tibiofemoral angle and range of motion of knee joint

    李广伟

    2012-01-01

    BACKGROUND: Application of total knee arthroplasty (TKA) for knee valgus deformity can be difficult technically in many aspects and exist a lot of controversy.OBJECTIVE: To investigate the clinical efficiency and surgical methods of TKA for knee valgus deformity in the adults.METHODS: Totally 15 knees from 12 patients underwent patellar lateral approach for proper osteotomy and selective lysis of the soft tissue to regain normal biomechanics and soft tissue balance of knee were selected. Posterior stabilized prosthesis was used for TKA to obtain the stability of the knee. After the surgery, rehabilitation therapy pertinently was adopted. Before and after the surgery, tibiofemoral angle was measured. Range of motion (ROM) was examined and HSS score was evaluated.RESULTS AND CONCLUSION: All patients were followed up over 6 months. Tibiofemoral angle decreased from 21.47° preoperatively to 5.47° postoperatively (P < 0.01). The ROM increased from 81.33° preoperatively to 121.07° postoperatively (P < 0.01). HSS score improved from 25.47 preoperatively to 89.87 postoperatively (P < 0.01). After replacement, 1 case affected more joint effusion, 2 cases affected knee instability. There was no dislocation or subluxation of the patella. Force line of lower limb returned to normal. TKA can effectively correct the knee valgus deformity, and can significantly improve the function of the knee.%背景:膝外翻畸形施行人工全膝关节置换难度很大,涉及面多,争议亦颇多.目的:观察全膝关节置换治疗成人膝外翻畸形的手术方法和临床效果.方法:对12例15膝采用髌骨内侧入路,正确截骨,选择性的软组织松解,恢复膝关节正常的力线和软组织平衡,采用后稳定型假体进行全膝关节置换,获得膝关节的稳定,置换后采取针对性的康复训练,置换前后测量胫股角,并置换后定期随访检查膝关节活动度并进行HSS评分.结果与结论:所有患者获得随访均>6

  18. After total knee arthroplasty, many people are not active enough to maintain their health and fitness : an observational study

    Groen, Jan-Willem; Stevens, Martin; Kersten, Roel F. M. R.; Reininga, Inge H. F.; van den Akker-Scheek, Inge

    2012-01-01

    Questions: What proportion of people after total knee arthroplasty adheres to the physical activity regimen recommended for maintenance of health (moderate intensity physical activity for at least 30 min on 5 days/week)? What proportion adheres to the activity regimen recommended to improve fitness

  19. Human-robot interaction: kinematics and muscle activity inside a powered compliant knee exoskeleton.

    Knaepen, Kristel; Beyl, Pieter; Duerinck, Saartje; Hagman, Friso; Lefeber, Dirk; Meeusen, Romain

    2014-11-01

    Until today it is not entirely clear how humans interact with automated gait rehabilitation devices and how we can, based on that interaction, maximize the effectiveness of these exoskeletons. The goal of this study was to gain knowledge on the human-robot interaction, in terms of kinematics and muscle activity, between a healthy human motor system and a powered knee exoskeleton (i.e., KNEXO). Therefore, temporal and spatial gait parameters, human joint kinematics, exoskeleton kinetics and muscle activity during four different walking trials in 10 healthy male subjects were studied. Healthy subjects can walk with KNEXO in patient-in-charge mode with some slight constraints in kinematics and muscle activity primarily due to inertia of the device. Yet, during robot-in-charge walking the muscular constraints are reversed by adding positive power to the leg swing, compensating in part this inertia. Next to that, KNEXO accurately records and replays the right knee kinematics meaning that subject-specific trajectories can be implemented as a target trajectory during assisted walking. No significant differences in the human response to the interaction with KNEXO in low and high compliant assistance could be pointed out. This is in contradiction with our hypothesis that muscle activity would decrease with increasing assistance. It seems that the differences between the parameter settings of low and high compliant control might not be sufficient to observe clear effects in healthy subjects. Moreover, we should take into account that KNEXO is a unilateral, 1 degree-of-freedom device.

  20. Knee problems and its associated factors among active cyclists in Eastern Province, Saudi Arabia

    Abdullatif K Althunyan

    2017-01-01

    Conclusion: Knee injuries are common with cyclists. Factors such as the type of the bicycle, the goal of bicycling, club type, body mass index, and participation in other sports play a significant role in the rate of knee pain.

  1. Knee hemarthrosis after arthroscopic surgery in an athlete with low factor XIII activity

    Tsujii Akira

    2012-10-01

    Full Text Available Abstract We report a thirteen-year-old tennis player with knee hemarthrosis caused by low factor XIII activity. She visited our hospital because of medial peripatellar pain for two years. Although there was no abnormal sign in X-ray or MRI, diagnostic arthroscopy was performed. It revealed some cartilage debris, medial plica and complete septum of suprapatellar plica. Removing the debris by washing out and resecting the medial plica, she could return to play tennis without perioperative symptom. Two months after the first operation, her knee got swelling without any apparent cause. Since 20 ml blood was aspirated twice and MRI revealed suprapatellar mass, we performed arthroscopy again. Suprapatellar mass was old blood clot covered with complete suprapatellar plica. Resection of suprapatellar plica and washing out blood clot were performed, and severe postoperative hemarthrosis was progressively occurred. As factor XIII level was 54% preoperatively, we diagnosed that this condition was caused by low activity level of the factor and administered factor XIII concentrates. The level got improved to 129% and then hemarthrosis gradually relieved. She had no signs of recurrence. We should keep in mind of low factor XIII activity case in case of unexplained postoperative hemarthrosis after arthroscopy because consumption of the factor might promote this condition.

  2. Knee hemarthrosis after arthroscopic surgery in an athlete with low factor XIII activity.

    Tsujii, Akira; Tanaka, Yoshinari; Yonetani, Yasukazu; Shiozaki, Yoshiki; Tomiyama, Yoshiaki; Horibe, Shuji

    2012-10-02

    We report a thirteen-year-old tennis player with knee hemarthrosis caused by low factor XIII activity. She visited our hospital because of medial peripatellar pain for two years. Although there was no abnormal sign in X-ray or MRI, diagnostic arthroscopy was performed. It revealed some cartilage debris, medial plica and complete septum of suprapatellar plica. Removing the debris by washing out and resecting the medial plica, she could return to play tennis without perioperative symptom. Two months after the first operation, her knee got swelling without any apparent cause. Since 20 ml blood was aspirated twice and MRI revealed suprapatellar mass, we performed arthroscopy again. Suprapatellar mass was old blood clot covered with complete suprapatellar plica. Resection of suprapatellar plica and washing out blood clot were performed, and severe postoperative hemarthrosis was progressively occurred. As factor XIII level was 54% preoperatively, we diagnosed that this condition was caused by low activity level of the factor and administered factor XIII concentrates. The level got improved to 129% and then hemarthrosis gradually relieved. She had no signs of recurrence. We should keep in mind of low factor XIII activity case in case of unexplained postoperative hemarthrosis after arthroscopy because consumption of the factor might promote this condition.

  3. Active Control Does Not Eliminate Motion-Induced Illusory Displacement

    Ian M. Thornton

    2011-05-01

    Full Text Available When the sine-wave grating of a Gabor patch drifts to the left or right, the perceived position of the entire object is shifted in the direction of local motion. In the current work we explored whether active control of the physical position of the patch overcomes such motion induced illusory displacement. In Experiment 1 we created a simple computer game and asked participants to continuously guide a Gabor patch along a randomly curving path using a joystick. When the grating inside the Gabor patch was stationary, participants could perform this task without error. When the grating drifted to either left or right, we observed systematic errors consistent with previous reports of motion-induced illusory displacement. In Experiment 2 we created an iPad application where the built-in accelerometer tilt control was used to steer the patch through as series of “gates”. Again, we observed systematic guidance errors that depended on the direction and speed of local motion. In conclusion, we found no evidence that participants could adapt or compensate for illusory displacement given active control of the target.

  4. The Effects of Knee Joint and Hip Abduction Angles on the Activation of Cervical and Abdominal Muscles during Bridging Exercises.

    Lee, Su-Kyoung; Park, Du-Jin

    2013-07-01

    [Purpose] The purpose of this study was to examine the effects of the flexion angle of the knee joint and the abduction angle of the hip joint on the activation of the cervical region and abdominal muscles. [Subjects] A total of 42 subjects were enrolled 9 males and 33 females. [Methods] The bridging exercise in this study was one form of exercise with a knee joint flexion angle of 90°. Based on this, a bridging exercise was conducted at the postures of abduction of the lower extremities at 0, 5, 10, and 15°. [Result] The changes in the knee joint angle and the hip abduction angle exhibited statistically significant effects on the cervical erector spinae, adductor magnus, and gluteus medius muscles. The abduction angles did not result in statistically significant effects on the upper trapezium, erector spinae, external oblique, and rectus abdominis muscles. However, in relation to the knee joint angles, during the bridging exercise, statistically significant results were exhibited. [Conclusion] When patients with both cervical and back pain do a bridging exercise, widening the knee joint angle would reduce cervical and shoulder muscle activity through minimal levels of abduction, permitting trunk muscle strengthening with reduced cervical muscle activity. This method would be helpful for strengthening trunk muscles in a selective manner.

  5. Age-related changes in kinematics of the knee joint during deep squat.

    Fukagawa, Shingo; Leardini, Alberto; Callewaert, Barbara; Wong, Pius D; Labey, Luc; Desloovere, Kaat; Matsuda, Shuichi; Bellemans, Johan

    2012-06-01

    Researchers frequently use the deep knee squat as a motor task in order to evaluate the kinematic performance after total knee arthroplasty. Many authors reported about the kinematics of a normal squatting motion, however, little is known on what the influence of aging is. Twenty-two healthy volunteers in various age groups (range 21-75 years) performed a deep knee squat activity while undergoing motion analysis using an optical tracking system. The influence of aging was evaluated with respect to kinematics of the trunk, hip, knee and ankle joints. Older subjects required significantly more time to perform a deep squat, especially during the descending phase. They also had more knee abduction and delayed peak knee flexion. Older subjects were slower in descend than ascend during the squat. Although older subjects had a trend towards less maximal flexion and less internal rotation of the knee compared to younger subjects, this difference was not significant. Older subjects also showed a trend towards more forward leaning of the trunk, resulting in increased hip flexion and anterior thoracic tilt. This study confirmed that some aspects of squat kinematics vary significantly with age, and that the basic methodology employed here can successfully detect these age-related trends. Older subjects had more abduction of the knee joint, and this may indicate the load distribution of the medial and lateral condyles could be different amongst ages. Age-matched control data are therefore required whenever the performance of an implant is evaluated during a deep knee squat.

  6. Thompson′s quadricepsplasty for stiff knee

    Kundu Z

    2007-01-01

    Full Text Available Background : Stiffness of the knee after trauma and/or surgery for femoral fractures is one of the most common complications and is difficult to treat. Stiffness in extension is more common and can be reduced by vigorous physiotherapy. If it does not improve then quadricepsplasty is indicated. The present study was undertaken to evaluate the results of Thompsons quadricepsplasty. Materials and Methods : 22 male patients (age range 20-45 years with posttraumatic knee stiffness following distal femoral fractures underwent Thompson′s quadricepsplasty where knee flexion range was less than 45°. The index injury in these patients was treated with plaster cast (n=5, plates (n=3, intramedullary nailing (n=3 and external fixator for open fractures (n=9. Thompson′s quadricepsplasty was performed in all the patients using anterior approach, with incision extending from upper thigh to tibial tubercle. Release of rectus femoris from underlying vastus intermedius and release of intraarticular adhesions were performed. After surgery the patients needed parentral analgesia for three days and then oral analgesics for three weeks. Active assisted knee mobilization exercises were started on the first post-operative day. Continous passive motion machine was used from the same day. Supervised physiotherapy was continued in hospital for six weeks followed by intensive knee flexion and extension exercise including cycling at home for atleast another six months. Results : Out of 22 patients, 20 had excellent to good results and two patients had poor results using criteria devised by Judet. One poor result was due to peroperative fracture of patella which was then internally fixed and hence the flexion of knee could not be started immediately. There was peroperative avulsion of tibial tuberosity in another patient who finally gained less than 50° knee flexion and hence a poor result. Conclusion : Thompsons quadricepsplasty followed by a strict and rigourous

  7. Development and preliminary testing of a computerized Animated Activity Questionnaire (AAQ) in patients with hip and knee osteoarthritis

    Peter, Wf; Loos, M; de Vet, Hcw

    2015-01-01

    Objective To develop an Animated Activity Questionnaire (AAQ), based on video animations, for assessing activity limitations in patients with hip/knee osteoarthritis (OA), which combines the advantages of self-reported questionnaires and performance-based tests, without many of their limitations......, 4) existing measurement instruments, and 5) focus groups of patients. Test-retest reliability was assessed in 30/110 patients. In 110 patients correlations were calculated between AAQ and self-reported Hip disability and Knee injury Osteoarthritis Outcome ADL subscale (H/KOOS). In 45/110 patients...

  8. Hybrid magnetic mechanism for active locomotion based on inchworm motion

    Kim, Sung Hoon; Hashi, Shuichiro; Ishiyama, Kazushi

    2013-02-01

    Magnetic robots have been studied in the past. Insect-type micro-robots are used in various biomedical applications; researchers have developed inchworm micro-robots for endoscopic use. A biological inchworm has a looping locomotion gait. However, most inchworm micro-robots depend on a general bending, or bellows, motion. In this paper, we introduce a new robotic mechanism using magnetic force and torque control in a rotating magnetic field for a looping gait. The proposed robot is controlled by the magnetic torque, attractive force, and body mechanisms (two stoppers, flexible body, and different frictional legs). The magnetic torque generates a general bending motion. In addition, the attractive force and body mechanisms produce the robot’s looping motion within a rotating magnetic field and without the use of an algorithm for field control. We verified the device’s performance and analyzed the motion through simulations and various experiments. The robot mechanism can be applied to active locomotion for various medical robots, such as wireless endoscopes.

  9. Individuals with medial knee osteoarthritis show neuromuscular adaptation when perturbed during walking despite functional and structural impairments.

    Kumar, Deepak; Swanik, Charles Buz; Reisman, Darcy S; Rudolph, Katherine S

    2014-01-01

    Neuromuscular control relies on sensory feedback that influences responses to changing external demands, and the normal response is for movement and muscle activation patterns to adapt to repeated perturbations. People with knee osteoarthritis (OA) are known to have pain, quadriceps weakness, and neuromotor deficits that could affect adaption to external perturbations. The aim of this study was to analyze neuromotor adaptation during walking in people with knee OA (n = 38) and controls (n = 23). Disability, quadriceps strength, joint space width, malalignment, and proprioception were assessed. Kinematic and EMG data were collected during undisturbed walking and during perturbations that caused lateral translation of the foot at initial contact. Knee excursions and EMG magnitudes were analyzed. Subjects with OA walked with less knee motion and higher muscle activation and had greater pain, limitations in function, quadriceps weakness, and malalignment, but no difference was observed in proprioception. Both groups showed increased EMG and decreased knee motion in response to the first perturbation, followed by progressively decreased EMG activity and increased knee motion during midstance over the first five perturbations, but no group differences were observed. Over 30 trials, EMG levels returned to those of normal walking. The results illustrate that people with knee OA respond similarly to healthy individuals when exposed to challenging perturbations during functional weight-bearing activities despite structural, functional, and neuromotor impairments. Mechanisms underlying the adaptive response in people with knee OA need further study.

  10. Knee Problems

    ... BMI Calculator myhealthfinder Immunization Schedules Nutrient Shortfall Questionnaire Knee ProblemsPain, swelling, stiffness and "water" on the knee are common symptoms. Follow this chart for more ...

  11. Thermally activated depinning motion of contact lines in pseudopartial wetting.

    Du, Lingguo; Bodiguel, Hugues; Colin, Annie

    2014-07-01

    We investigate pressure-driven motion of liquid-liquid menisci in circular tubes, for systems in pseudopartial wetting conditions. The originality of this type of wetting lies in the coexistence of a macroscopic contact angle with a wetting liquid film covering the solid surface. Focusing on small capillary numbers, we report observations of an apparent contact angle hysteresis at first sight similar to the standard partial wetting case. However, this apparent hysteresis exhibits original features. We observe very long transient regimes before steady state, up to several hundreds of seconds. Furthermore, in steady state, the velocities are nonzero, meaning that the contact line is not strongly pinned to the surface defects, but are very small. The velocity of the contact line tends to vanish near the equilibrium contact angle. These observations are consistent with the thermally activated depinning theory that has been proposed to describe partial wetting systems on disordered substrates and suggest that a single physical mechanism controls both the hysteresis (or the pinning) and the motion of the contact line. The proposed analysis leads to the conclusion that the depinning activated energy is lower with pseudopartial wetting systems than with partial wetting ones, allowing the direct observation of the thermally activated motion of the contact line.

  12. Fuzzy Modelling of Knee Joint with Genetic Optimization

    B. S. K. K. Ibrahim

    2011-01-01

    Full Text Available Modelling of joint properties of lower limbs in people with spinal cord injury is significantly challenging for researchers due to the complexity of the system. The objective of this study is to develop a knee joint model capable of relating electrical parameters to dynamic joint torque as well as knee angle for functional electrical stimulation application. The joint model consists of a segmental dynamic, time-invariant passive properties and uncertain time-variant active properties. The knee joint model structure comprising optimised equations of motion and fuzzy models to represent the passive viscoelasticity and active muscle properties is formulated. The model thus formulated is optimised using genetic optimization, and validated against experimental data. The developed model can be used for simulation of joint movements as well as for control development. The results show that the model developed gives an accurate dynamic characterisation of the knee joint.

  13. Motion sickness and tilts of the inertial force environment: active suspension systems vs. active passengers

    Golding, J.F.; Bles, W.; Bos, J.E.; Haynes, T.; Gresty, M.A.

    2003-01-01

    Maneuvering in vehicles exposes occupants to low frequency forces (<1 Hz) which can provoke motion sickness. Hypothesis: Aligning with the tilting inertial resultant (gravity + imposed horizontal acceleration: gravito-inertial force (GIF)) may reduce motion sickness when tilting is either 'active' (

  14. Collective motion in an active suspension of Escherichia coli bacteria

    Gachelin, J.; Rousselet, A.; Lindner, A.; Clement, E.

    2014-02-01

    We investigate experimentally the emergence of collective motion in the bulk of an active suspension of Escherichia coli bacteria. When increasing the concentration from a dilute to a semi-dilute regime, we observe a continuous crossover from a dynamical cluster regime to a regime of ‘bio-turbulence’ convection patterns. We measure a length scale characterizing the collective motion as a function of the bacteria concentration. For bacteria fully supplied with oxygen, the increase of the correlation length is almost linear with concentration and at the largest concentrations tested, the correlation length could be as large as 24 bacterial body sizes (or 7-8 when including the flagella bundle). In contrast, under conditions of oxygen shortage the correlation length saturates at a value of around 7 body lengths.

  15. Motion of Euglena gracilis: Active fluctuations and velocity distribution

    Romanczuk, P.; Romensky, M.; Scholz, D.; Lobaskin, V.; Schimansky-Geier, L.

    2015-07-01

    We study the velocity distribution of unicellular swimming algae Euglena gracilis using optical microscopy and active Brownian particle theory. To characterize a peculiar feature of the experimentally observed distribution at small velocities we use the concept of active fluctuations, which was recently proposed for the description of stochastically self-propelled particles [Romanczuk, P. and Schimansky-Geier, L., Phys. Rev. Lett. 106, 230601 (2011)]. In this concept, the fluctuating forces arise due to internal random performance of the propulsive motor. The fluctuating forces are directed in parallel to the heading direction, in which the propulsion acts. In the theory, we introduce the active motion via the depot model [Schweitzer, et al., Phys. Rev. Lett. 80(23), 5044 (1998)]. We demonstrate that the theoretical predictions based on the depot model with active fluctuations are consistent with the experimentally observed velocity distributions. In addition to the model with additive active noise, we obtain theoretical results for a constant propulsion with multiplicative noise.

  16. Muscle activation and knee biomechanics during squatting and lunging after lower extremity fatigue in healthy young women.

    Longpré, Heather S; Acker, Stacey M; Maly, Monica R

    2015-02-01

    Muscle activations and knee joint loads were compared during squatting and lunging before and after lower extremity neuromuscular fatigue. Electromyographic activations of the rectus femoris, vastus lateralis and biceps femoris, and the external knee adduction and flexion moments were collected on 25 healthy women (mean age 23.5 years, BMI of 23.7 kg/m(2)) during squatting and lunging. Participants were fatigued through sets of 50 isotonic knee extensions and flexions, with resistance set at 50% of the peak torque achieved during a maximum voluntary isometric contraction. Fatigue was defined as a decrease in peak isometric knee extension or flexion torque ≥25% from baseline. Co-activation indices were calculated between rectus femoris and biceps femoris; and between vastus lateralis and biceps femoris. Fatigue decreased peak isometric extension and flexion torques (pknee adduction and flexion moments during lunging (p<0.05). Quadriceps activations were greater during lunging than squatting (p<0.05). Thus, fatigue altered the recruitment strategy of the quadriceps during squatting and lunging. Lunging challenges quadriceps activation more than squatting in healthy, young women.

  17. The Effects of Knee Joint and Hip Abduction Angles on the Activation of Cervical and Abdominal Muscles during Bridging Exercises

    Lee, Su-Kyoung; Park, Du-Jin

    2013-01-01

    [Purpose] The purpose of this study was to examine the effects of the flexion angle of the knee joint and the abduction angle of the hip joint on the activation of the cervical region and abdominal muscles. [Subjects] A total of 42 subjects were enrolled 9 males and 33 females. [Methods] The bridging exercise in this study was one form of exercise with a knee joint flexion angle of 90°. Based on this, a bridging exercise was conducted at the postures of abduction of the lower extremities at 0...

  18. Diabetes that impacts on routine activities predicts slower recovery after total knee arthroplasty: an observational study

    Nurudeen Amusat

    2014-12-01

    Full Text Available Question: In the 6 months after total knee arthroplasty (TKA, what is the pattern of pain resolution and functional recovery in people without diabetes, with diabetes that does not impact on routine activities, and with diabetes that does impact on routine activities? Is diabetes that impacts on routine activities an independent predictor of slower resolution of pain and functional recovery after TKA? Design: Community-based prospective observational study. Participants: A consecutive cohort of 405 people undergoing primary TKA, of whom 60 (15% had diabetes. Participants with diabetes were also asked preoperatively whether diabetes impacted on their routine activities. Participants were categorised into three groups: no diabetes (n = 345, diabetes with no impact on activities (n = 41, and diabetes that impacted activities (n = 19. Outcome measures: Pain and function were measured using the Western Ontario and McMaster Universities (WOMAC Osteoarthritis Index within the month before surgery and 1, 3 and 6 months after surgery. Demographic, medical and surgical factors were also measured, along with depression, social support and health-related quality of life. Results: No baseline differences in pain and function were seen among the three groups (p > 0.05. Adjusting for age, gender and contralateral joint involvement across the 6 postoperative months, participants with diabetes that impacted on routine activities had pain scores that were 8.3 points higher (indicating greater pain and function scores that were 5.4 points higher (indicating lower function than participants without diabetes. Participants with diabetes that doesn’t impact on routine activities had similar recovery to those without diabetes. Conclusion: People undergoing TKA who report preoperatively that diabetes impacts on their routine activities have less recovery over 6 months than those without diabetes or those with diabetes that does not impact on routine activities

  19. Knee Bursitis

    ... make a diagnosis of knee bursitis during a physical exam. Your doctor will inspect your knee by: Comparing the condition of both knees, particularly if only one is painful Gently pressing on different areas of your knee to detect warmth, swelling and the source of pain Carefully moving ...

  20. Factors associated with physical activity in patients with osteoarthritis of the hip or knee: a systematic review.

    Veenhof, C.; Huisman, P.A.; Barten, J.A.; Takken, T.; Pisters, M.F.

    2012-01-01

    OBJECTIVE: To give an overview of factors related to the level of physical activity in patients with hip or knee osteoarthritis (OA). METHODS: An extensive systematic literature search was conducted in PubMed, CINAHL and Embase. Inclusion criteria were: studies on patients with a diagnosis of OA of

  1. Effectiveness of behavioral graded activity in patients with osteoarthritis of the hip and/or knee: A randomized clinical trial.

    Veenhof, C.; Koke, A.J.; Dekker, J.; Oostendorp, R.A.B.; Bijlsma, J.W.J.; Tulder, M.W. van; Ende, C.H.M. van den

    2006-01-01

    OBJECTIVE: To determine the effectiveness of a behavioral graded activity program (BGA) compared with usual care (UC; exercise therapy and advice) according to the Dutch guidelines for physiotherapy in patients with osteoarthritis (OA) of the hip and/or knee. The BGA intervention is intended to incr

  2. Physical activity and exercise adherence in physical therapy exercise treatment in patients with osteoarthritis of hip or knee.

    Pisters, M.F.; Veenhof, C.; Bakker, D. de; Schellevis, F.G.; Dekker, J.

    2008-01-01

    Purpose: a lack of regular physical activity in patients with osteoarthritis (OA) of the hip and/or knee is an important risk factor for functional decline. The ultimate goal of exercise therapy is to improve the overall physical function and to help individuals meet the demands of daily living. Ear

  3. Effectiveness of behavioral graded activity in patients with osteoarthritis of hip and/or knee: a randomized clinical trial.

    Veenhof, C.; Köke, A.J.A.; Dekker, J.; Oostendorp, R.A.; Bijlsma, J.W.J.; Tulder, M.W. van; Ende, C.H.M. van den

    2006-01-01

    Objective: To determine the effectiveness of a behavioral graded activity program (BGA) compared with usual care (UC; exercise therapy and advice) according to the Dutch guidelines for physiotherapy in patients with osteoarthritis (OA) of the hip and/or knee. The BGA intervention is intended to incr

  4. Fusion of smartphone motion sensors for physical activity recognition.

    Shoaib, Muhammad; Bosch, Stephan; Incel, Ozlem Durmaz; Scholten, Hans; Havinga, Paul J M

    2014-06-10

    For physical activity recognition, smartphone sensors, such as an accelerometer and a gyroscope, are being utilized in many research studies. So far, particularly, the accelerometer has been extensively studied. In a few recent studies, a combination of a gyroscope, a magnetometer (in a supporting role) and an accelerometer (in a lead role) has been used with the aim to improve the recognition performance. How and when are various motion sensors, which are available on a smartphone, best used for better recognition performance, either individually or in combination? This is yet to be explored. In order to investigate this question, in this paper, we explore how these various motion sensors behave in different situations in the activity recognition process. For this purpose, we designed a data collection experiment where ten participants performed seven different activities carrying smart phones at different positions. Based on the analysis of this data set, we show that these sensors, except the magnetometer, are each capable of taking the lead roles individually, depending on the type of activity being recognized, the body position, the used data features and the classification method employed (personalized or generalized). We also show that their combination only improves the overall recognition performance when their individual performances are not very high, so that there is room for performance improvement. We have made our data set and our data collection application publicly available, thereby making our experiments reproducible.

  5. Fusion of Smartphone Motion Sensors for Physical Activity Recognition

    Muhammad Shoaib

    2014-06-01

    Full Text Available For physical activity recognition, smartphone sensors, such as an accelerometer and a gyroscope, are being utilized in many research studies. So far, particularly, the accelerometer has been extensively studied. In a few recent studies, a combination of a gyroscope, a magnetometer (in a supporting role and an accelerometer (in a lead role has been used with the aim to improve the recognition performance. How and when are various motion sensors, which are available on a smartphone, best used for better recognition performance, either individually or in combination? This is yet to be explored. In order to investigate this question, in this paper, we explore how these various motion sensors behave in different situations in the activity recognition process. For this purpose, we designed a data collection experiment where ten participants performed seven different activities carrying smart phones at different positions. Based on the analysis of this data set, we show that these sensors, except the magnetometer, are each capable of taking the lead roles individually, depending on the type of activity being recognized, the body position, the used data features and the classification method employed (personalized or generalized. We also show that their combination only improves the overall recognition performance when their individual performances are not very high, so that there is room for performance improvement. We have made our data set and our data collection application publicly available, thereby making our experiments reproducible.

  6. Motion of Euglena Gracilis: Active Fluctuations and Velocity Distribution

    Romanczuk, Pawel; Scholz, Dimitri; Lobaskin, Vladimir; Schimansky-Geier, Lutz

    2015-01-01

    We study the velocity distribution of unicellular swimming algae Euglena gracilis using optical microscopy and theory. To characterize a peculiar feature of the experimentally observed distribution at small velocities we use the concept of active fluctuations, which was recently proposed for the description of stochastically self-propelled particles [Romanczuk, P. and Schimansky-Geier, L., Phys. Rev. Lett. 106, 230601 (2011)]. In this concept, the fluctuating forces arise due to internal random performance of the propulsive motor. The fluctuating forces are directed in parallel to the heading direction, in which the propulsion acts. In the theory, we introduce the active motion via the depot model [Schweitzer et al., Phys. Rev. Lett. 80, 23, 5044 (1998)]. We demonstrate that the theoretical predictions based on the depot model with active fluctuations are consistent with the experimentally observed velocity distributions. In addition to the model with additive active noise, we obtain theoretical results for a...

  7. Strength asymmetry of the knee extensors and physical activity in middle-aged women

    Michal Lehnert

    2014-09-01

    Full Text Available Background: Differences between muscle strength and power of lower limbs is one of the factors associated with falls in the elderly population. Muscle strength asymmetry of lower limbs increases with age. Objective: The aim of the study is to assess differences in the volume and intensity of physical activity (PA in the subgroups of women being at higher and lower risk of falls (with and without strength asymmetry of the knee extensors of dominant and non-dominant lower limb. Methods: Data from 42 women (age 56.3 ± 4.4 years; weight 76.5 ± 16.1 kg; body height 164.3 ± 5.2 cm; body mass index 28.1 ± 5.3 kg . m-2 were used for the purpose of the presented analysis. Furthermore the sample was divided into subgroups with lower and higher strength asymmetry of quadriceps muscle (as a criterion the asymmetry greater than 15% was chosen. Absolute concentric peak torque of the knee extensors was evaluated by an isokinetic dynamometer IsoMed 2000 in a sitting position at angular velocity of 180° . s-1. PA was monitored using Yamax SW-700 pedometers throughout 7 consecutive days and using the Czech version of standardized International Physical Activity Questionnaire. Results: Statistically significant differences between groups with lower and higher strength asymmetry were found in the amount of self-reported vigorous PA (p = .04; d = 0.6 only. Differences between the observed groups were not significant in self-reported moderate PA and walking. There were also no significant differences in the daily numbers of steps measured objectively. Conclusions: The results of the study indicate that from the point of view of strength asymmetry of knee extensors as a factor associated with falls in middle-aged women, intensity of PA could be an important characteristic of PA. This suggestion should be taken into account in habitual PA and training programs in middle-aged population.

  8. In Vivo Healthy Knee Kinematics during Dynamic Full Flexion

    Satoshi Hamai

    2013-01-01

    Full Text Available Healthy knee kinematics during dynamic full flexion were evaluated using 3D-to-2D model registration techniques. Continuous knee motions were recorded during full flexion in a lunge from 85° to 150°. Medial and lateral tibiofemoral contacts and femoral internal-external and varus-valgus rotations were analyzed as a function of knee flexion angle. The medial tibiofemoral contact translated anteroposteriorly, but remained on the center of the medial compartment. On the other hand, the lateral tibiofemoral contact translated posteriorly to the edge of the tibial surface at 150° flexion. The femur exhibited external and valgus rotation relative to the tibia over the entire activity and reached 30° external and 5° valgus rotations at 150° flexion. Kinematics’ data during dynamic full flexion may provide important insight as to the designing of high-flexion total knee prostheses.

  9. Peak triceps surae muscle activity is not specific to knee flexion angles during MVIC.

    Hébert-Losier, Kim; Schneiders, Anthony G; García, José A; Sullivan, S John; Simoneau, Guy G

    2011-10-01

    There is limited research on peak activity of the separate triceps surae muscles in select knee flexion (KF) positions during a maximum voluntary isometric contraction (MVIC) used to normalize EMG signals. The aim of this study was to determine how frequent peak activity occurred during an MVIC for soleus (SOL), gastrocnemius medialis (GM), and gastrocnemius lateralis (GL) in select KF positions, and if these peaks were recorded in similar KF positions. Forty-eight healthy individuals performed unilateral plantar-flexion MVIC in standing with 0°KF and 45°KF, and in sitting with 90°KF. Surface EMG of SOL, GM, and GL were collected and processed in 250 ms epochs to determine peak root-mean-square amplitude. Peak activity was most frequently captured in standing and rarely in sitting, with no position selective to SOL, GM or GL activity. Peak GM and GL activity was more frequent in 0°KF than 45°KF, and more often in similar KF positions than not. Peak SOL activity was just as likely in 45°KF as 0°KF, and more in positions similar to GM, but not GL. The EMG amplitudes were at least 20% greater in positions that captured peak activity over those that did not. The overall findings support performing an MVIC in more than one KF position to normalize triceps surae EMG. It is emphasized that no KF position is selective to SOL, GM, or GL alone.

  10. Differential brain activity states during the perception and nonperception of illusory motion as revealed by magnetoencephalography.

    Crowe, David A; Leuthold, Arthur C; Georgopoulos, Apostolos P

    2010-12-28

    We studied visual perception using an annular random-dot motion stimulus called the racetrack. We recorded neural activity using magnetoencephalography while subjects viewed variants of this stimulus that contained no inherent motion or various degrees of embedded motion. Subjects reported seeing rotary motion during viewing of all stimuli. We found that, in the absence of any motion signals, patterns of brain activity differed between states of motion perception and nonperception. Furthermore, when subjects perceived motion, activity states within the brain did not differ across stimuli of different amounts of embedded motion. In contrast, we found that during periods of nonperception brain-activity states varied with the amount of motion signal embedded in the stimulus. Taken together, these results suggest that during perception the brain may lock into a stable state in which lower-level signals are suppressed.

  11. Evaluation of a variable resistance orthotic knee joint.

    Herbert-Copley, Andrew; Lemaire, Edward D; Baddour, Natalie

    2016-08-01

    Knee-ankle-foot orthoses (KAFOs) are full leg braces for individuals with knee extensor weakness, designed to support the person during weight bearing activities by preventing knee flexion. KAFOs typically result in an unnatural gait pattern and are primarily used for level ground walking. A novel variable resistance orthotic knee joint, the Ottawalk-Variable Speed (OWVS), was designed to address these limitations. This paper presents a pilot test to evaluate the OWVS functional performance during walking and stair descent. A carbon-fiber KAFO was adjusted for an able-bodied participant by a certified orthotist, with a standard orthotic single axis knee joint on the medial side and the OWVS on the lateral side. The participant performed level ground walking (stance-control, open, closed) and stair descent tests. The operator was able to manually switch between closed mode in terminal swing to open mode in terminal stance for stance-control walking. Knee angle kinematics were similar between open and stance control modes. For stair descent, resistance settings supported the participant as they lowered their body to the next step, but with smaller range of motion compared to the open setting. The Ottawalk-Variable Speed design successfully controls knee flexion during stance and stair descent, with one lateral control joint. Mode switching was fast and appropriate. This microprocessor controlled SCKAFO has a low profile that fits beneath clothing and the variable resistance design will allow people to negotiate different terrain types.

  12. Muscle Activation Differs between Three Different Knee Joint-Angle Positions during a Maximal Isometric Back Squat Exercise

    Paulo Henrique Marchetti

    2016-01-01

    Full Text Available The purpose of this study was to compare muscle activation of the lower limb muscles when performing a maximal isometric back squat exercise over three different positions. Fifteen young, healthy, resistance-trained men performed an isometric back squat at three knee joint angles (20°, 90°, and 140° in a randomized, counterbalanced fashion. Surface electromyography was used to measure muscle activation of the vastus lateralis (VL, vastus medialis (VM, rectus femoris (RF, biceps femoris (BF, semitendinosus (ST, and gluteus maximus (GM. In general, muscle activity was the highest at 90° for the three quadriceps muscles, yet differences in muscle activation between knee angles were muscle specific. Activity of the GM was significantly greater at 20° and 90° compared to 140°. The BF and ST displayed similar activation at all joint angles. In conclusion, knee position alters muscles activation of the quadriceps and gluteus maximus muscles. An isometric back squat at 90° generates the highest overall muscle activation, yet an isometric back squat at 140° generates the lowest overall muscle activation of the VL and GM only.

  13. Physical performance and self-report outcomes associated with use of passive, adaptive, and active prosthetic knees in persons with unilateral, transfemoral amputation: Randomized crossover trial

    Brian J. Hafner, PhD

    2015-09-01

    Full Text Available Prosthetic knees are a vital component in an artificial limb. Contemporary knees include passive (mechanical, adaptive (computerized, or active (motorized control systems and have the potential to mitigate amputation-related functional impairments and activity limitations. A 14 mo randomized crossover trial was conducted. Participants (n = 12, mean age = 58 yr were tested under three conditions: passive control (existing knee, adaptive control (Ossur Rheo Knee II, and active control (Ossur Power Knee II. Training and acclimation time were provided to participants in the adaptive and active knees. Outcome measures included indoor tests (Timed Up and Go test [TUG], stairs, and ramp, outdoor tests (walking course and perceived exertion, step activity monitor, self-report surveys (mobility, balance confidence, physical function, fatigue, and general health, and fall incidence. Mixed-effects linear regression modeling was used to evaluate data. Compared with passive control, adaptive control significantly improved comfortable TUG time (difference = 0.91 s, p = 0.001 and reported physical function (difference = 1.26 [T-score], p = 0.03. Active control significantly increased comfortable TUG, fast TUG, and ramp times (difference = 3.02, 2.66, and 0.96 s, respectively, all p < 0.03 and increased balance confidence (difference = 3.77, p = 0.003 compared with passive control. Findings suggest that adaptive knee control may enhance function compared with passive control but that active control can restrict mobility in middle-age or older users with transfemoral amputation.

  14. Effect of exercise therapy on neuromuscular activity and knee strength in female adolescents with patellofemoral pain

    Rathleff, Michael S.; Samani, Afshin; Olesen, Jens L.;

    2016-01-01

    . A random subsample of 57 female adolescents was included and tested at baseline and after 3months. Neuromuscular control of the knee was quantified as the complexity of surface electromyography of the vastus lateralis and vastus medialis during stair descent. Secondary outcomes were complexity of knee...

  15. Knee complaints seen in general practice : active sport participants versus non-sport participants

    van Middelkoop, Marienke; van Linschoten, Robbart; Berger, Marjolein Y.; Koes, Bart W.; Bierma-Zeinstra, Sita M. A.

    2008-01-01

    Background: Since knee complaints are common among athletes and are frequently presented in general practice, it is of interest to investigate the type of knee complaints represented in general practice of athletes in comparison with those of non-athletes. Therefore, the aim of this study is to inve

  16. Generation of physiological parameter sets for hip joint motions and loads during daily life activities for application in wear simulators of the artificial hip joint.

    Fabry, Christian; Herrmann, Sven; Kaehler, Michael; Klinkenberg, Ernst-Dieter; Woernle, Christoph; Bader, Rainer

    2013-01-01

    At present, wear investigations of total hip replacements are performed in accordance with the ISO standard 14242, which is based on simplified kinematic and force data of the gait cycle. The aim of this analytical study was to generate parameter sets of daily life activities in order to replicate more realistic joint load situations in wear testing. Hence, published in vivo motion and force data of daily life activities were evaluated and adjusted using analytical techniques. The created kinematically and dynamically consistent parameter sets comprised time trajectories of three Cardan angles to describe the motion of the femur with respect to the pelvis and time trajectories of three force components, representing the hip joint contact force. The parameter sets include the activities of walking, knee bending, stair climbing and a combined load case of sitting down and standing up. Additionally, a motion sequence following the frequency of daily life activities was presented. Differences of the evaluated angular motions and joint contact forces in comparison to the ISO standard 14242-1 were pointed out. The results of this study offer the possibility to extend the kinematics and dynamics of the ISO standard test protocol and to support the loading conditions of hip wear simulators with a comprehensive set of motions and loads close to reality.

  17. Knee problems and its associated factors among active cyclists in Eastern Province, Saudi Arabia

    Althunyan, Abdullatif K.; Darwish, Magdy A.; Abdel Wahab, Moataza M.

    2017-01-01

    INTRODUCTION: Bicycling is one of the most enjoyable aerobic exercises recommended for the promotion of an individual's health. The Eastern Province of Saudi Arabia has seen a huge increase in the number of people who cycle. People have different goals for bicycling, but the injuries they sustain are common. Most of them relate to overuse, particularly of lower body joints. This study was conducted to determine the prevalence of knee problems and factors associated with knee pain in cyclists. MATERIALS AND METHODS: A cross-sectional study was conducted in October 2015, using an online self-administered questionnaire. The questionnaire was based on pertinent literature, was piloted, and validated. A web link was sent to 513 cyclists (professional and amateur) using E-mail, WhatsApp application, or SMS. Three hundred and eleven responses were received, 283 of which were included in the analysis. RESULTS: The overall prevalence of knee pain was 25.8%; 27.6% for amateur cyclists and 15.9% for professional cyclists. Only 17.2% knee pain was attributed to cycling, whereas in 32.8% it happened spontaneously and in 25% of cases it occurred while running. Majority of the cyclists reported pain as mild (61.6%) or moderate (28.7%); anterior knee pain accounted for 58.1% knee pain. Different goals of cycling and different bicycle types had statistically significant difference on the rate of knee pain. Of underweight cyclists, 62.2% reported knee pain. Cyclists who run more or participated in football had a higher rate of pain. CONCLUSION: Knee injuries are common with cyclists. Factors such as the type of the bicycle, the goal of bicycling, club type, body mass index, and participation in other sports play a significant role in the rate of knee pain. PMID:28163572

  18. Assessing the Relative Contributions of Active Ankle and Knee Assistance to the Walking Mechanics of Transfemoral Amputees Using a Powered Prosthesis.

    Ingraham, Kimberly A; Fey, Nicholas P; Simon, Ann M; Hargrove, Levi J

    2016-01-01

    Powered knee-ankle prostheses are capable of providing net-positive mechanical energy to amputees. Yet, there are limitless ways to deliver this energy throughout the gait cycle. It remains largely unknown how different combinations of active knee and ankle assistance affect the walking mechanics of transfemoral amputees. This study assessed the relative contributions of stance phase knee swing initiation, increasing ankle stiffness and powered plantarflexion as three unilateral transfemoral amputees walked overground at their self-selected walking speed. Five combinations of knee and ankle conditions were evaluated regarding the kinematics and kinetics of the amputated and intact legs using repeated measures analyses of variance. We found eliminating active knee swing initiation or powered plantarflexion was linked to increased compensations of the ipsilateral hip joint during the subsequent swing phase. The elimination of knee swing initiation or powered plantarflexion also led to reduced braking ground reaction forces of the amputated and intact legs, and influenced both sagittal and frontal plane loading of the intact knee joint. Gradually increasing prosthetic ankle stiffness influenced the shape of the prosthetic ankle plantarflexion moment, more closely mirroring the intact ankle moment. Increasing ankle stiffness also corresponded to increased prosthetic ankle power generation (despite a similar maximum stiffness value across conditions) and increased braking ground reaction forces of the amputated leg. These findings further our understanding of how to deliver assistance with powered knee-ankle prostheses and the compensations that occur when specific aspects of assistance are added/removed.

  19. Assessing the Relative Contributions of Active Ankle and Knee Assistance to the Walking Mechanics of Transfemoral Amputees Using a Powered Prosthesis.

    Kimberly A Ingraham

    Full Text Available Powered knee-ankle prostheses are capable of providing net-positive mechanical energy to amputees. Yet, there are limitless ways to deliver this energy throughout the gait cycle. It remains largely unknown how different combinations of active knee and ankle assistance affect the walking mechanics of transfemoral amputees. This study assessed the relative contributions of stance phase knee swing initiation, increasing ankle stiffness and powered plantarflexion as three unilateral transfemoral amputees walked overground at their self-selected walking speed. Five combinations of knee and ankle conditions were evaluated regarding the kinematics and kinetics of the amputated and intact legs using repeated measures analyses of variance. We found eliminating active knee swing initiation or powered plantarflexion was linked to increased compensations of the ipsilateral hip joint during the subsequent swing phase. The elimination of knee swing initiation or powered plantarflexion also led to reduced braking ground reaction forces of the amputated and intact legs, and influenced both sagittal and frontal plane loading of the intact knee joint. Gradually increasing prosthetic ankle stiffness influenced the shape of the prosthetic ankle plantarflexion moment, more closely mirroring the intact ankle moment. Increasing ankle stiffness also corresponded to increased prosthetic ankle power generation (despite a similar maximum stiffness value across conditions and increased braking ground reaction forces of the amputated leg. These findings further our understanding of how to deliver assistance with powered knee-ankle prostheses and the compensations that occur when specific aspects of assistance are added/removed.

  20. Assessing the Relative Contributions of Active Ankle and Knee Assistance to the Walking Mechanics of Transfemoral Amputees Using a Powered Prosthesis

    Simon, Ann M.; Hargrove, Levi J.

    2016-01-01

    Powered knee-ankle prostheses are capable of providing net-positive mechanical energy to amputees. Yet, there are limitless ways to deliver this energy throughout the gait cycle. It remains largely unknown how different combinations of active knee and ankle assistance affect the walking mechanics of transfemoral amputees. This study assessed the relative contributions of stance phase knee swing initiation, increasing ankle stiffness and powered plantarflexion as three unilateral transfemoral amputees walked overground at their self-selected walking speed. Five combinations of knee and ankle conditions were evaluated regarding the kinematics and kinetics of the amputated and intact legs using repeated measures analyses of variance. We found eliminating active knee swing initiation or powered plantarflexion was linked to increased compensations of the ipsilateral hip joint during the subsequent swing phase. The elimination of knee swing initiation or powered plantarflexion also led to reduced braking ground reaction forces of the amputated and intact legs, and influenced both sagittal and frontal plane loading of the intact knee joint. Gradually increasing prosthetic ankle stiffness influenced the shape of the prosthetic ankle plantarflexion moment, more closely mirroring the intact ankle moment. Increasing ankle stiffness also corresponded to increased prosthetic ankle power generation (despite a similar maximum stiffness value across conditions) and increased braking ground reaction forces of the amputated leg. These findings further our understanding of how to deliver assistance with powered knee-ankle prostheses and the compensations that occur when specific aspects of assistance are added/removed. PMID:26807889

  1. Coupling of Active Motion and Advection Shapes Intracellular Cargo Transport

    Trong, P Khuc; Goldstein, R E; 10.1103/PhysRevLett.109.028104

    2012-01-01

    Intracellular cargo transport can arise from passive diffusion, active motor-driven transport along cytoskeletal filament networks, and passive advection by fluid flows entrained by such motor/cargo motion. Active and advective transport are thus intrinsically coupled as related, yet different representations of the same underlying network structure. A reaction-advection-diffusion system is used here to show that this coupling affects the transport and localization of a passive tracer in a confined geometry. For sufficiently low diffusion, cargo localization to a target zone is optimized either by low reaction kinetics and decoupling of bound and unbound states, or by a mostly disordered cytoskeletal network with only weak directional bias. These generic results may help to rationalize subtle features of cytoskeletal networks, for example as observed for microtubules in fly oocytes.

  2. Knee complaints seen in general practice: active sport participants versus non-sport participants

    Koes Bart W

    2008-03-01

    Full Text Available Abstract Background Since knee complaints are common among athletes and are frequently presented in general practice, it is of interest to investigate the type of knee complaints represented in general practice of athletes in comparison with those of non-athletes. Therefore, the aim of this study is to investigate the differences in type of knee complaints between sport participants, in this study defined as athletes, and non-sport participants, defined as non-athletes, presenting in general practice. Further, differences in the initial policy of the GP, medical consumption, and outcome at one-year follow-up were also investigated. Methods Patients consulting their GP for a new episode of knee complaints were invited to participate in this prospective cohort study. From the total HONEUR knee cohort population (n = 1068 we extracted patients who were athletes (n = 421 or non-athletes (n = 388. Results The results showed that acute distortions of the knee were significantly more diagnosed in athletes than in non-athletes (p = 0.04. Further, more athletes were advised by their GP to 'go easy on the knee' than the non-athletes (p Conclusion There are no major differences in the diagnosis and prognosis of knee complaints between athletes and non-athletes presented to the GP. This implies that there are no indications for different treatment strategies applied in both groups. However, athletes are more often advised to 'go easy on the knee' and to rest than non-athletes. Further, there is a trend towards increased medical consumption among athletes while functional disability and pain are lower than among the non-athletes.

  3. Knee Injuries

    ... bursitis . Symptoms of bursitis in the knee include warmth, tenderness, swelling, and pain on the front of ... injury without the aid of a television screen. Physical Therapy Depending on the type of knee injury ...

  4. The effect of total knee arthroplasty on knee joint kinematics and kinetics during gait.

    Hatfield, Gillian L; Hubley-Kozey, Cheryl L; Astephen Wilson, Janie L; Dunbar, Michael J

    2011-02-01

    This study determined how total knee arthroplasty (TKA) altered knee motion and loading during gait. Three-dimensional kinematic and kinetic gait patterns of 42 patients with severe knee osteoarthritis were collected 1 week prior and 1-year post-TKA. Principal component analysis extracted major patterns of variability in the gait waveforms. Overall and midstance knee adduction moment magnitude decreased. Overall knee flexion angle magnitude increased due to an increase during swing. Increases in the early stance knee flexion moment and late stance knee extension moment were found, indicating improved impact attenuation and function. A decrease in the early stance knee external rotation moment indicated alteration in the typical rotation mechanism. Most changes moved toward an asymptomatic pattern and would be considered improvements in motion, function, and loading.

  5. Unwinding motion of a twisted active region filament

    Yan, X. L.; Xue, Z. K.; Kong, D. F. [Yunnan Observatories, Chinese Academy of Sciences, Kunming 650011 (China); Liu, J. H. [Department of Physics, Shijiazhuang University, Shijiazhuang 050035 (China); Xu, C. L. [Yunnan Normal University, Kunming 650092 (China)

    2014-12-10

    To better understand the structures of active region filaments and the eruption process, we study an active region filament eruption in active region NOAA 11082 in detail on 2010 June 22. Before the filament eruption, the opposite unidirectional material flows appeared in succession along the spine of the filament. The rising of the filament triggered two B-class flares at the upper part of the filament. As the bright material was injected into the filament from the sites of the flares, the filament exhibited a rapid uplift accompanying the counterclockwise rotation of the filament body. From the expansion of the filament, we can see that the filament consisted of twisted magnetic field lines. The total twist of the filament is at least 5π obtained by using a time slice method. According to the morphology change during the filament eruption, it is found that the active region filament was a twisted flux rope and its unwinding motion was like a solar tornado. We also find that there was a continuous magnetic helicity injection before and during the filament eruption. It is confirmed that magnetic helicity can be transferred from the photosphere to the filament. Using the extrapolated potential fields, the average decay index of the background magnetic fields over the filament is 0.91. Consequently, these findings imply that the mechanism of solar filament eruption could be due to the kink instability and magnetic helicity accumulation.

  6. Unwinding motion of a twisted active-region filament

    Yan, X L; Liu, J H; Kong, D F; Xu, C L

    2014-01-01

    To better understand the structures of active-region filaments and the eruption process, we study an active-region filament eruption in active region NOAA 11082 in detail on June 22, 2010. Before the filament eruption, the opposite unidirectional material flows appeared in succession along the spine of the filament. The rising of the filament triggered two B-class flares at the upper part of the filament. As the bright material was injected into the filament from the sites of the flares, the filament exhibited a rapid uplift accompanying the counterclockwise rotation of the filament body. From the expansion of the filament, we can see that the filament is consisted of twisted magnetic field lines. The total twist of the filament is at least 5$\\pi$ obtained by using time slice method. According to the morphology change during the filament eruption, it is found that the active-region filament was a twisted flux rope and its unwinding motion was like a solar tornado. We also find that there was a continuous magn...

  7. Unwinding Motion of a Twisted Active Region Filament

    Yan, X. L.; Xue, Z. K.; Liu, J. H.; Kong, D. F.; Xu, C. L.

    2014-12-01

    To better understand the structures of active region filaments and the eruption process, we study an active region filament eruption in active region NOAA 11082 in detail on 2010 June 22. Before the filament eruption, the opposite unidirectional material flows appeared in succession along the spine of the filament. The rising of the filament triggered two B-class flares at the upper part of the filament. As the bright material was injected into the filament from the sites of the flares, the filament exhibited a rapid uplift accompanying the counterclockwise rotation of the filament body. From the expansion of the filament, we can see that the filament consisted of twisted magnetic field lines. The total twist of the filament is at least 5π obtained by using a time slice method. According to the morphology change during the filament eruption, it is found that the active region filament was a twisted flux rope and its unwinding motion was like a solar tornado. We also find that there was a continuous magnetic helicity injection before and during the filament eruption. It is confirmed that magnetic helicity can be transferred from the photosphere to the filament. Using the extrapolated potential fields, the average decay index of the background magnetic fields over the filament is 0.91. Consequently, these findings imply that the mechanism of solar filament eruption could be due to the kink instability and magnetic helicity accumulation.

  8. Modulation of muscle activity and force fluctuations in the plantarflexors after bedrest depends on knee position.

    Yoshitake, Yasuhide; Kouzaki, Motoki; Fukuoka, Hideoki; Fukunaga, Tetsuo; Shinohara, Minoru

    2007-06-01

    Force fluctuations in leg muscles increase after bedrest, perhaps due to modulation of the neural strategy that is specific to a muscle or common to agonist muscles. The purpose of this study was to examine the modulation of muscle activity and force fluctuations during steady contractions with variable involvement of plantarflexor muscles after bedrest at knee-flexed (FLX) and extended (EXT) positions. Before and after 20-day bedrest, plantarflexion force and surface electromyogram (EMG) in the medial gastrocnemius (MG), lateral gastrocnemius, and soleus muscles were measured during steady isometric contractions in five young men. In EXT, power EMG of MG increased significantly after bedrest. This low-frequency modulation of muscle activity in MG accompanied a 29% increase in the standard deviation of force. There was no change in EMG in other muscles. In FLX, there was no adjustment in EMG or force fluctuations. These results suggest that low-frequency modulation of MG plays a role in increasing force fluctuations during steady plantarflexion in EXT after bedrest. The findings indicate task/muscle specificity in the modulation of neural strategy during steady contractions after bedrest and underscore the importance of designing a specific training regimen targeted to particular tasks/muscles with regard to force fluctuations in multiple-agonist systems.

  9. UTILIZATION OF PULSED ELECTROMAGNETIC FIELD AND TRADITIONAL PHYSIOTHERAPY IN KNEE OSTEOARTHRITIS MANAGEMENT

    Kadrya H. Battecha

    2015-04-01

    Full Text Available Background and Objectives: Pulsed electromagnetic field (PEMF has been suggested as a treatment method for musculoskeletal system disorders. The present study was conducted to determine whether the addition of PEMF to traditional physiotherapy produces better clinical outcomes than traditional physiotherapy alone in the management of moderate knee osteoarthritis (OA. Design: A single-blinded, randomized controlled study Methods: Twenty subjects (5 men and 15 women with unilateral moderate knee OA (Kellgren-Lawrence criteria grade 2. They were randomly allocated in 2 groups to receive: group (A PEMF plus ultrasound plus exercises; or (B ultrasound plus exercises. Both groups received the respective treatments 3 times per week for 4 weeks and underwent the same pretreatment and post treatment evaluation that included active knee range of motion (ROM by universal goniometer, knee pain score by visual analogue scale (VAS and knee functional performance by Western Ontario and McMaster Universities osteoarthritis index (WOMAC. Result: There was an improvement in both groups in active knee flexion ROM, reduced VAS score and improved WOMAC index , however, all outcomes were significantly better in group (A (p <0.05. Moreover, the percentages of outcomes improvement were in favor of group (A. Conclusion: The addition of PEMF to traditional physiotherapy in managing Knee OA produced a greater improvement in pain relief, range of motion and resulted in better functional performance than did traditional physiotherapy alone. The improvement in current study should be limited to short term outcomes of PEMF.

  10. The effect of active recovery, cold water immersion and passive recovery on subsequent knee extension and flexion strength

    Barbora Strejcová

    2012-09-01

    Full Text Available BACKGROUND: Recovery is an important aspect of every physical activity. Many athletes train hard without giving their body time to recover which can lead to overreaching, burnout or poor performance. Currently cold-water immersion recovery and active recovery have emerged as some of the most popular interventions enabling faster recovery. OBJECTIVE: To assess the effect of three kinds of recovery (active recovery, cold water immersion, passive recovery on medium-term knee strength in the extension and flexion. METHODS: Fourteen athletes at the age of 26.6 ± 4.4 years performed, in a random cross-over design, 3 sessions with 3 repeated medium-term isokinetic tests. The effect of active recovery, passive rest and cold water immersion were assessed by 3 × 3 (time × recovery repeated-measure ANOVA, respectively. The dependent variables were – peak torque, total work and average power. RESULTS: We found significantly lower absolute differences between the first and third trial in knee extension for peak torque after the active recovery (↑ 0.9 N × m than after the cold water immersion (↓ 14.6 N × m or the passive recovery (↓ 13.9 N × m. The decrease of the average power was significantly lower differences after the active recovery (↓ 5 W than after the cold water immersion (↓ 23.7 W or passive recovery (↓ 25.9 W. The changes in total work were not significant. We did not found any changes in the isokinetic strength for the knee flexors after different kinds of recovery. Maximal heart rate (HRmax was significantly higher during the active recovery than during the cold water immersion and the passive recovery (173 ± 14, 166 ± 14 and 167 ± 14 rpm. We have found significant differences in the average heart rates (HRavg during active recovery, cold water immersion and passive recovery (124 ± 8, 97 ± 9 and 107 ± 12 rpm. CONCLUSION: We found the positive effect of the active recovery on the subsequent medium-term performance for

  11. Prosthetic knee design by simulation

    Hollerbach, K; Hollister, A

    1999-07-30

    Although 150,000 total knee replacement surgeries are performed annually in North America, current designs of knee prostheses have mechanical problems that include a limited range of motion, abnormal gait patterns, patellofemoral joint dysfunction, implant loosening or subsidence, and excessive wear. These problems fall into three categories: failure to reproduce normal joint kinematics, which results in altered limb function; bone-implant interface failure; and material failure. Modern computer technology can be used to design, prototype, and test new total knee implants. The design team uses the full range of CAD-CAM to design and produce implant prototypes for mechanical and clinical testing. Closer approximation of natural knee kinematics and kinetics is essential for improved patient function and diminished implant loads. Current knee replacement designs are based on 19th Century theories that the knee moves about a variable axis of rotation. Recent research has shown, however, that knee motion occurs about two fixed, offset axes of rotation. These aces are not perpendicular to the long axes of the bones or to each other, and the axes do not intersect. Bearing surfaces of mechanisms that move about axes of rotation are surfaces of revolution of those axes which advanced CAD technology can produce. Solids with surfaces of revolution for the two axes of rotation for the knee have been made using an HP9000 workstation and Structural Ideas Master Series CAD software at ArthroMotion. The implant's CAD model should closely replicate movements of the normal knee. The knee model will have a range of flexion-extension (FE) from -5 to 120 degrees. Movements include varus, valgus, internal and external rotation, as well as flexion and extension. The patellofemoral joint is aligned perpendicular to the FE axis and replicates the natural joint more closely than those of existing prostheses. The bearing surfaces will be more congruent than current designs and should

  12. Effects of therapeutic exercise and hydrotherapy on pain severity and knee range of motion in patients with hemophilia: A randomized controlled trial

    Vahid Mazloum

    2014-01-01

    Conclusions: Using hydrotherapy in addition to usual rehabilitation training can result in beneficial effect in terms of pain and knee joint ROM. However, it appears that hydrotherapy is more effective in reducing pain.

  13. Primary visual cortex activity along the apparent-motion trace reflects illusory perception.

    Lars Muckli

    2005-08-01

    Full Text Available The illusion of apparent motion can be induced when visual stimuli are successively presented at different locations. It has been shown in previous studies that motion-sensitive regions in extrastriate cortex are relevant for the processing of apparent motion, but it is unclear whether primary visual cortex (V1 is also involved in the representation of the illusory motion path. We investigated, in human subjects, apparent-motion-related activity in patches of V1 representing locations along the path of illusory stimulus motion using functional magnetic resonance imaging. Here we show that apparent motion caused a blood-oxygenation-level-dependent response along the V1 representations of the apparent-motion path, including regions that were not directly activated by the apparent-motion-inducing stimuli. This response was unaltered when participants had to perform an attention-demanding task that diverted their attention away from the stimulus. With a bistable motion quartet, we confirmed that the activity was related to the conscious perception of movement. Our data suggest that V1 is part of the network that represents the illusory path of apparent motion. The activation in V1 can be explained either by lateral interactions within V1 or by feedback mechanisms from higher visual areas, especially the motion-sensitive human MT/V5 complex.

  14. The use of the greater trochanter marker in the thigh segment model:Implications for hip and knee frontal and transverse plane motion

    Valentina Graci; Gretchen B. Salsich

    2016-01-01

    Background: The greater trochanter marker is commonly used in 3-dimensional (3D) models; however, its influence on hip and knee kinematics during gait is unclear. Understanding the influence of the greater trochanter marker is important when quantifying frontal and transverse plane hip and knee kinematics, parameters which are particularly relevant to investigate in individuals with conditions such as patellofemoral pain, knee osteoarthritis, anterior cruciate ligament (ACL) injury, and hip pain. The aim of this study was to evaluate the effect of including the greater trochanter in the construction of the thigh segment on hip and knee kinematics during gait. Methods: 3D kinematics were collected in 19 healthy subjects during walking using a surface marker system. Hip and knee angles were compared across two thigh segment definitions (with and without greater trochanter) at two time points during stance:peak knee flexion (PKF) and minimum knee flexion (MinKF). Results: Hip and knee angles differed in magnitude and direction in the transverse plane at both time points. In the thigh model with the greater trochanter the hip was more externally rotated than in the thigh model without the greater trochanter (PKF:−9.34° ± 5.21° vs. 1.40° ± 5.22°, MinKF:−5.68° ± 4.24° vs. 5.01° ± 4.86°;p<0.001). In the thigh model with the greater trochanter, the knee angle was more internally rotated compared to the knee angle calculated using the thigh definition without the greater trochanter (PKF:14.67° ± 6.78° vs. 4.33° ± 4.18°, MinKF:10.54° ± 6.71° vs.−0.01° ± 2.69°;p<0.001). Small but significant differences were detected in the sagittal and frontal plane angles at both time points (p<0.001). Conclusion: Hip and knee kinematics differed across different segment definitions including or excluding the greater trochanter marker, especially in the transverse plane. Therefore when considering whether to include the greater trochanter in the thigh segment

  15. Construction of an in vivo motion evaluation system for the knee joint of athletes%运动员膝关节在体运动检测系统的建立

    宋军; 李凭跃; 游辅宇; 孔祥雪; 肖菊姣; 李鉴轶

    2013-01-01

    目的 探讨利用2D/3D图像配准技术建立运动员膝关节在体运动检测系统的可行性.方法 采集1名健康成年志愿者(男性,37岁)左侧膝关节的CT影像,进行三维重建获得骨结构的三维模型.取志愿者保持约30°屈曲的2张X线片,在3Ds Max7软件系统中构建虚拟X线系统,采用2D/3D图像配准技术重现膝关节的位置,将CT数据中胫骨作为配准基点并利用逆向工程技术计算摄X线片时膝关节的相对运动. 结果 经2D/3D图像配准可还原膝关节的三维空间位置.逆向工程技术计算结果显示:与采集CT数据时的位置相比,摄X线片时左侧股骨下段相对位移X轴为0.01mm,Y轴为5.20 mm,Z轴为2.05 mm;相对角度X轴为26.67°,Y轴为-0.97°,Z轴为-15.14°. 结论 利用2D/3D图像配准技术可实现膝关节的在体运动评价,但其配准效率尚需进一步研究.%Objective To construct an in vivo motion evaluation system for the knee joint of athletes using 2D/3D registration.Methods CT data of the left knee from a male 37-year-old healthy adult volunteer were collected for 3D reconstruction of computer model of the knee joint.Two orthogonal images of the knee at a 30° flexion angle were captured using 2 C-arm fluoroscopic machines that were perpendicular to each other.A virtual fluoroscopy was then created in software 3Ds Max for reconstruction of the relative positions of the 2 orthogonal images.The 3D computer models of the left femur and tibia were then introduced into the virtual fluoroscopy respectively before they were projected onto the orthogonal images by 2 virtual cameras.The 3D positions of the knee joint were determined by matching the projections of the knee model to the orthogonal images of the knee.After the tibia in the CT data was taken as the base position for registration,the relatively displacements and angles of the femur were calculated with the reverse engineering technique.Results After 2D/3D registration,the 3D positions

  16. Total Knee Replacement

    ... walking, swimming, golf, driving, light hiking, biking, ballroom dancing, and other low-impact sports. With appropriate activity ... help prevent leg swelling and blood clots. Physical Therapy Most patients begin exercising their knee the day ...

  17. Rough terrain motion planning for actively reconfigurable mobile robots

    Brunner, Michael

    2015-02-05

    In the aftermath of the Tohoku earthquake and the nuclear meltdown at the power plant of Fukushima Daiichi in 2011, reconfigurable robots like the iRobot Packbot were deployed. Instead of humans, the robots were used to investigate contaminated areas. Other incidents are the two major earthquakes in Northern Italy in May 2012. Besides many casualties, a large number of historical buildings was severely damaged. Due to the imminent danger of collapse, it was too dangerous for rescue personnel to enter many of the buildings. Therefore, the sites were inspected by reconfigurable robots, which are able to traverse the rubble and debris of the partially destroyed buildings. This thesis develops a navigation system enabling wheeled and tracked robots to safely traverse rough terrain and challenging structures. It consists of a planning mechanism and a controller. The focus of this thesis, however, is on the contribution to motion planning. The planning scheme employs a hierarchical approach to motion planning for actively reconfigurable robots in rough environments. Using a map of the environment the algorithm estimates the traversability under the consideration of uncertainties. Based on this analysis, an initial path search determines an approximate solution with respect to the robot's operating limits.Subsequently, a detailed planning step refines the initial path where it is required. The refinement step considers the robot's actuators and stability in addition to the quantities of the first search. Determining the robot-terrain interaction is very important in rough terrain. This thesis presents two path refinement approaches: a deterministic and a randomized approach. The experimental evaluation investigates the separate components of the planning scheme, the robot-terrain interaction for instance.In simulation as well as in real world experiments the evaluation demonstrates the necessity of such a planning algorithm in rough terrain and it provides

  18. Quantifying thigh muscle co-activation during isometric knee extension contractions: within- and between-session reliability.

    Katsavelis, Dimitrios; Threlkeld, A Joseph

    2014-08-01

    Muscle co-activation around the knee is important during ambulation and balance. The wide range of methodological approaches for the quantification of co-activation index (CI) makes comparisons across studies and populations difficult. The present study determined within- and between-session reliability of different methodological approaches for the quantification of the CI of the knee extensor and flexor muscles during maximum voluntary isometric contractions (MVICs). Eight healthy volunteers participated in two repeated testing sessions. A series of knee extension MVICs of the dominant leg with concomitant torque and electromyographic (EMG) recordings were captured. CI was calculated utilizing different analytical approaches. Intraclass correlation coefficient (ICC) showed that within-session measures displayed higher reliability (ICC>0.861) and lower variability (Coefficient of variation; CV24.2%). A selection of a 500ms or larger window of RMS EMG activity around the PT delivered more reliable and less variable results than other approaches. Our findings suggest that the CI can provide a reliable measure for comparisons among conditions and is best utilized for within-session experimental designs.

  19. Viewing the motion of human body parts activates different regions of premotor, temporal, and parietal cortex.

    Wheaton, Kylie J; Thompson, James C; Syngeniotis, Ari; Abbott, David F; Puce, Aina

    2004-05-01

    Activation of premotor and temporoparietal cortex occurs when we observe others movements, particularly relating to objects. Viewing the motion of different body parts without the context of an object has not been systematically evaluated. During a 3T fMRI study, 12 healthy subjects viewed human face, hand, and leg motion, which was not directed at or did not involve an object. Activation was identified relative to static images of the same human face, hand, and leg in both individual subject and group average data. Four clear activation foci emerged: (1) right MT/V5 activated to all forms of viewed motion; (2) right STS activated to face and leg motion; (3) ventral premotor cortex activated to face, hand, and leg motion in the right hemisphere and to leg motion in the left hemisphere; and (4) anterior intraparietal cortex (aIP) was active bilaterally to viewing hand motion and in the right hemisphere leg motion. In addition, in the group data, a somatotopic activation pattern for viewing face, hand, and leg motion occurred in right ventral premotor cortex. Activation patterns in STS and aIP were more complex--typically activation foci to viewing two types of human motion showed some overlap. Activation in individual subjects was similar; however, activation to hand motion also occurred in the STS with a variable location across subjects--explaining the lack of a clear activation focus in the group data. The data indicate that there are selective responses to viewing motion of different body parts in the human brain that are independent of object or tool use.

  20. Within- and between-session reliability of the maximal voluntary knee extension torque and activation.

    Park, Jihong; Hopkins, J Ty

    2013-01-01

    A ratio between the torque generated by maximal voluntary isometric contraction (MVIC) and exogenous electrical stimulus, central activation ratio (CAR), has been widely used to assess quadriceps function. To date, no data exist regarding between-session reliability of this measurement. Thirteen neurologically sound volunteers underwent three testing sessions (three trials per session) with 48 hours between-session. Subjects performed MVICs of the quadriceps with the knee locked at 90° flexion and the hip at 85°. Once the MVIC reached a plateau, an electrical stimulation from superimposed burst technique (SIB: 125 V with peak output current 450 mA) was manually delivered and transmitted directly to the quadriceps via stimulating electrodes. CAR was calculated by using the following equation: CAR = MVIC torque/MVIC + SIB torque. Intraclass correlation coefficients (ICC) were calculated within- (ICC((2,1))) and between-session (ICC((2,k))) for MVIC torques and CAR values. Our data show that quadriceps MVIC and CAR are very reliable both within- (ICC((2,1)) = 0.99 for MVIC; 0.94 for CAR) and between-measurement sessions (ICC((2,k)) = 0.92 for MVIC; 0.86 for CAR) in healthy young adults. For clinical research, more data of the patients with pathological conditions are required to ensure reproducibility of calculation of CAR.

  1. Effects of image noise, respiratory motion, and motion compensation on 3D activity quantification in count-limited PET images

    Siman, W.; Mawlawi, O. R.; Mikell, J. K.; Mourtada, F.; Kappadath, S. C.

    2017-01-01

    The aims of this study were to evaluate the effects of noise, motion blur, and motion compensation using quiescent-period gating (QPG) on the activity concentration (AC) distribution—quantified using the cumulative AC volume histogram (ACVH)—in count-limited studies such as 90Y-PET/CT. An International Electrotechnical Commission phantom filled with low 18F activity was used to simulate clinical 90Y-PET images. PET data were acquired using a GE-D690 when the phantom was static and subject to 1-4 cm periodic 1D motion. The static data were down-sampled into shorter durations to determine the effect of noise on ACVH. Motion-degraded PET data were sorted into multiple gates to assess the effect of motion and QPG on ACVH. Errors in ACVH at AC90 (minimum AC that covers 90% of the volume of interest (VOI)), AC80, and ACmean (average AC in the VOI) were characterized as a function of noise and amplitude before and after QPG. Scan-time reduction increased the apparent non-uniformity of sphere doses and the dispersion of ACVH. These effects were more pronounced in smaller spheres. Noise-related errors in ACVH at AC20 to AC70 were smaller (15%). The accuracy of ACmean was largely independent of the total count. Motion decreased the observed AC and skewed the ACVH toward lower values; the severity of this effect depended on motion amplitude and tumor diameter. The errors in AC20 to AC80 for the 17 mm sphere were  -25% and  -55% for motion amplitudes of 2 cm and 4 cm, respectively. With QPG, the errors in AC20 to AC80 of the 17 mm sphere were reduced to  -15% for motion amplitudes  0.5, QPG was effective at reducing errors in ACVH despite increases in image non-uniformity due to increased noise. ACVH is believed to be more relevant than mean or maximum AC to calculate tumor control and normal tissue complication probability. However, caution needs to be exercised when using ACVH in post-therapy 90Y imaging because of its susceptibility to image

  2. Influence factors of range of motion after total knee arthroplasty%影响全膝关节置换术后关节活动度的相关因素分析

    曾勉东; 杨波; 谢景开; 吕玉明; 尹彪

    2012-01-01

    目的 分析全膝关节置换术后关节活动度的相关影响因素,旨在探讨如何提高术后膝关节活动范围.方法 回顾性研究2008年10月~2010年10月37例全膝关节置换术.术后1年25例膝关节屈曲度>90°的患者作为对照组,12例膝关节屈曲度<90°的患者作为实验组.两组根据年龄、性别、体重指数(BMI)、手术时间、术中出血和随访时间等进行配对病例对照研究分析影响因素.结果 两组患者年龄、性别、手术时间、术中出血、随访时间及术前合并症比较,差异无统计学意义.手术前后两组膝关节屈曲度比较,差异有显著统计学意义(P<0.01).手术前后两组的胫骨倾斜度与关节力线对位不良的比较,差异有统计学意义(P<0.05).结论 全膝关节置换术后膝关节活动度受肥胖、下肢力线对位情况和术后主动功能锻炼等因素影响,术中术后减少以上因素影响可以提高膝关节术后活动度.%Objective To analyze the related factors of the range of motion(ROM) after total knee arthroplasty and discuss how to improve the ROM of knee. Methods A retrospective review was given to the data from 37 patients undergoing total knee arthroplasty between October 2008 and October 2010. There're 25 TKA patients with greater than 90° flexion at 1 year postoperative served as control group, 12 patients with a 1 -year postoperative flexion range of less than 90° was taken as treatment group. The age, sex, body mass index, time for surgery, intraoperative bleeding, follow-up time of the control group were matched to those of the treatment group. Results No significant differences were found with regard to the age,sex,body mass index, time for surgery, intraoperative bleeding, follow-up time. Significant differences were found between preoperative flexion and postopeartive flexion (P <0.01). Preoperative and postoperative the gradient of tibial and force line of lower extremities were significantly

  3. Effect of two different kinesio taping techniques on knee kinematics and kinetics in young females

    Guner, Senem; Alsancak, Serap; Koz, Mitat

    2015-01-01

    [Purpose] The application of kinesio taping may improve strength and performance, inhibit and facilitate motor activity, and increase range of motion. The aim of this study was to compare the effects of kinesio taping facilitation and inhibition applications on spatiotemporal knee kinematics and kinetics during walking activity in healthy subjects. [Subjects and Methods] A three-dimensional quantitative gait evaluation was performed without tape and with, facilitation and inhibition kinesio taping application on the knee. Sixteen healthy female college students (age, 19.7 ± 0.4 years; height, 1.64 ± 3.4 cm; body mass, 51.5 ± 4.8 kg) participated in the study. [Results] Spatiotemporal parameters (cadence, walking speed, stride length) were significantly different among the trials. Knee joint sagittal plane range of motion was not different with either kinesio taping application. Knee external flexion moment during the early stance phase decreased significantly with facilitation kinesio taping and increased with the inhibition kinesio taping. Knee external extension moment during the mid-stance phase increased with facilitation kinesio taping. Knee power parameters, eccentric activity in the rectus femoris during the pre-swing phase was significantly increased with inhibition kinesio taping application, while eccentric activity of the hamstrings during the terminal swing of gait was decreased. [Conclusion] These findings showed that facilitation kinesio taping application affected the terminal stance phase and that inhibition kinesio taping influenced the terminal swing phase compared with the no tape condition. PMID:26644651

  4. Effect of two different kinesio taping techniques on knee kinematics and kinetics in young females.

    Guner, Senem; Alsancak, Serap; Koz, Mitat

    2015-10-01

    [Purpose] The application of kinesio taping may improve strength and performance, inhibit and facilitate motor activity, and increase range of motion. The aim of this study was to compare the effects of kinesio taping facilitation and inhibition applications on spatiotemporal knee kinematics and kinetics during walking activity in healthy subjects. [Subjects and Methods] A three-dimensional quantitative gait evaluation was performed without tape and with, facilitation and inhibition kinesio taping application on the knee. Sixteen healthy female college students (age, 19.7 ± 0.4 years; height, 1.64 ± 3.4 cm; body mass, 51.5 ± 4.8 kg) participated in the study. [Results] Spatiotemporal parameters (cadence, walking speed, stride length) were significantly different among the trials. Knee joint sagittal plane range of motion was not different with either kinesio taping application. Knee external flexion moment during the early stance phase decreased significantly with facilitation kinesio taping and increased with the inhibition kinesio taping. Knee external extension moment during the mid-stance phase increased with facilitation kinesio taping. Knee power parameters, eccentric activity in the rectus femoris during the pre-swing phase was significantly increased with inhibition kinesio taping application, while eccentric activity of the hamstrings during the terminal swing of gait was decreased. [Conclusion] These findings showed that facilitation kinesio taping application affected the terminal stance phase and that inhibition kinesio taping influenced the terminal swing phase compared with the no tape condition.

  5. Knee kinematics and kinetics in former soccer players with a 16-year-old ACL injury – the effects of twelve weeks of knee-specific training

    Holmström Eva

    2007-04-01

    Full Text Available Abstract Background Training of neuromuscular control has become increasingly important and plays a major role in rehabilitation of subjects with an injury to the anterior cruciate ligament (ACL. Little is known, however, of the influence of this training on knee stiffness during loading. Increased knee stiffness occurs as a loading strategy of ACL-injured subjects and is associated with increased joint contact forces. Increased or altered joint loads contribute to the development of osteoarthritis. The aim of the study was to determine if knee stiffness, defined by changes in knee kinetics and kinematics of gait, step activity and cross-over hop could be reduced through a knee-specific 12-week training programme. Methods A 3-dimensional motion analysis system (VICON and a force plate (AMTI were used to calculate knee kinetics and kinematics before and after 12 weeks of knee-specific training in 12 males recruited from a cohort with ACL injury 16 years earlier. Twelve uninjured males matched for age, sex, BMI and activity level served as a reference group. Self-reported patient-relevant data were obtained by the KOOS questionnaire. Results There were no significant changes in knee stiffness during gait and step activity after training. For the cross-over hop, increased peak knee flexion during landing (from 44 to 48 degrees, p = 0.031 and increased internal knee extensor moment (1.28 to 1.55 Nm/kg, p = 0.017 were seen after training, indicating reduced knee stiffness. The KOOS sport and recreation score improved from 70 to 77 (p = 0.005 and was significantly correlated with the changes in knee flexion during landing for the cross-over hop (r = 0.6, p = 0.039. Conclusion Knee-specific training improved lower extremity kinetics and kinematics, indicating reduced knee stiffness during demanding hop activity. Self-reported sport and recreational function correlated positively with the biomechanical changes supporting a clinical importance of the

  6. The effect of ankle bracing on knee kinetics and kinematics during volleyball-specific tasks.

    West, T; Ng, L; Campbell, A

    2014-12-01

    The purpose of this study was to examine the effects of ankle bracing on knee kinetics and kinematics during volleyball tasks. Fifteen healthy, elite, female volleyball players performed a series of straight-line and lateral volleyball tasks with no brace and when wearing an ankle brace. A 14-camera Vicon motion analysis system and AMTI force plate were used to capture the kinetic and kinematic data. Knee range of motion, peak knee anterior-posterior and medial-lateral shear forces, and peak ground reaction forces that occurred between initial contact with the force plate and toe off were compared using paired sample t-tests between the braced and non-braced conditions (P volleyball tasks. However, ankle bracing was demonstrated to reduce knee lateral shear forces during all of the lateral movement volleyball tasks. Wearing the Active Ankle T2 brace will not impact knee joint range of motion and may in fact reduce shear loading to the knee joint in volleyball players.

  7. Activity Increase Despite Arthritis (AÏDA: design of a Phase II randomised controlled trial evaluating an active management booklet for hip and knee osteoarthritis [ISRCTN24554946

    Edwards Rhiannon T

    2009-09-01

    Full Text Available Abstract Background Hip and knee osteoarthritis is a common cause of pain and disability, which can be improved by exercise interventions. However, regular exercise is uncommon in this group because the low physical activity level in the general population is probably reduced even further by pain related fear of movement. The best method of encouraging increased activity in this patient group is not known. A booklet has been developed for patients with hip or knee osteoarthritis. It focuses on changing disadvantageous beliefs and encouraging increased physical activity. Methods/Design This paper describes the design of a Phase II randomised controlled trial (RCT to test the effectiveness of this new booklet for patients with hip and knee osteoarthritis in influencing illness and treatment beliefs, and to assess the feasibility of conducting a larger definitive RCT in terms of health status and exercise behaviour. A computerised search of four general medical practice patients' record databases will identify patients older than 50 years of age who have consulted with hip or knee pain in the previous twelve months. A random sample of 120 will be invited to participate in the RCT comparing the new booklet with a control booklet, and we expect 100 to return final questionnaires. This trial will assess the feasibility of recruitment and randomisation, the suitability of the control intervention and outcome measurement tools, and will provide an estimate of effect size. Outcomes will include beliefs about hip and knee pain, beliefs about exercise, fear avoidance, level of physical activity, health status and health service costs. They will be measured at baseline, one month and three months. Discussion We discuss the merits of testing effectiveness in a phase II trial, in terms of intermediate outcome measures, whilst testing the processes for a larger definitive trial. We also discuss the advantages and disadvantages of testing the psychometric

  8. Implied motion because of instability in Hokusai Manga activates the human motion-sensitive extrastriate visual cortex: an fMRI study of the impact of visual art.

    Osaka, Naoyuki; Matsuyoshi, Daisuke; Ikeda, Takashi; Osaka, Mariko

    2010-03-10

    The recent development of cognitive neuroscience has invited inference about the neurosensory events underlying the experience of visual arts involving implied motion. We report functional magnetic resonance imaging study demonstrating activation of the human extrastriate motion-sensitive cortex by static images showing implied motion because of instability. We used static line-drawing cartoons of humans by Hokusai Katsushika (called 'Hokusai Manga'), an outstanding Japanese cartoonist as well as famous Ukiyoe artist. We found 'Hokusai Manga' with implied motion by depicting human bodies that are engaged in challenging tonic posture significantly activated the motion-sensitive visual cortex including MT+ in the human extrastriate cortex, while an illustration that does not imply motion, for either humans or objects, did not activate these areas under the same tasks. We conclude that motion-sensitive extrastriate cortex would be a critical region for perception of implied motion in instability.

  9. Total knee replacement for posttraumatic degenerative arthritis of the knee

    WU Li-dong; XIONG Yan; YAN Shi-gui; YANG Quan-sen

    2005-01-01

    Objective: To evaluate the results of total knee arthroplasty (TKA) in patients with posttraumatic degenerative arthritis due to a previous fracture around the knee. Methods: We analyzed the results of 15 TKAs, performed from 1997 to 2003, in 15 patients with post-traumatic degenerative arthritis due to a previous fracture around knee. There were 3 women and 12 men with an average age of 58 years (range, 31-76 years). The time from fracture to arthroplasty averaged 8.2 years (range, 2-27 years). Internal fixation had previously been performed in 8 patients resulting in retained hardware. At the time of arthroplasty a femoral fracture malunion was present in two knees. Lateral retinacular release (4 knees), extensor mechanism realignment (1 knee) or medial collateral ligament reconstruction (1 knee) were needed at the time of arthroplasty. Results: Follow-up averaged 35 months (range, 12-73 months). No patient was lost for follow-up. According to the Knee Society Score scale, the mean preoperative knee score was 37 (range, 10-70) and functional score was 41 (range, 0-60). They were improved significantly to a mean of 84 (range, 10-100) and 76 (range, 20-100) points, respectively at the latest follow-up. The mean knee arc of motion were improved from 84° preoperation to 94° at the latest follow-up. Postoperative manipulation under anesthesia for poor motion was carried out in 4 knees. No knee had aseptic loosening that required subsequent revision. Two knees developed superficial infection and were treated with debridement. It subsequently recovered with the retention of components. Conclusions: Significant improvement in function and relief of pain has been achieved in patients with previous fractures undergoing subsequent TKA. However, this procedure is technically demanding and patients are at increased risk for restricted motion and need more care following TKA. This study suggests that the outcome of TKA may be improved further by making special efforts to

  10. Investigation the efficacy of intra-articular prolotherapy with erythropoietin and dextrose and intra-articular pulsed radiofrequency on pain level reduction and range of motion improvement in primary osteoarthritis of knee

    Poupak Rahimzadeh

    2014-01-01

    Full Text Available Background: Osteoarthritis is one of the most common diseases and the knee is the most commonly affected joint. Intra-articular prolotherapy is being utilized in acute and chronic pain management setting. This study was designed to compare the efficacy of three methods of intra-articular knee joint therapies with erythropoietin, dextrose, and pulsed radiofrequency. Materials and Methods: After approval by the Ethics Committee and explaining the therapeutic method to volunteers, 70 patients who were suffering from primary knee osteoarthrosis went through one of the treatment methods (erythropoietin, dextrose, and pulsed radiofrequency. The study was double-blind randomized clinical trial performed from December 2012 to July 2013. Patients′ pain level was assessed through the visual analog pain scale (VAS, and range of motion (ROM was measured by goniometric method. Furthermore, patients′ satisfaction was assessed before and after different treatment methods in weeks 2, 4, and 12. For analysis, Chi-square, one-way ANOVA, and repeated measured ANOVA were utilized. Results: The demographic results among the three groups did not indicate any statistical difference. The mean VAS in erythropoietin group in the 2 nd , 4 th , and 12 th weeks was 3.15 ± 1.08, 3.15 ± 1.08, and 3.5 ± 1.23, respectively (P ≤ 0.005. Knee joint ROM in the erythropoietin group in the 2 nd , 4 th , and 12 th weeks was 124 ± 1.50, 124 ± 1.4, and 123 ± 1.53 respectively (P ≤ 0.005. Satisfaction score in the 12 th week in erythropoietin group was extremely satisfied 15%, satisfied 55%, and moderately satisfied 30%, (P = 0.005. No specific side-effects were observed. Conclusion: Intra-articular prolotherapy with erythropoietin was more effective in terms of pain level reduction and ROM improvement compared with dextrose and pulsed radiofrequency.

  11. Immediate effect of Masai Barefoot Technology shoes on knee joint moments in women with knee osteoarthritis.

    Tateuchi, Hiroshige; Taniguchi, Masashi; Takagi, Yui; Goto, Yusuke; Otsuka, Naoki; Koyama, Yumiko; Kobayashi, Masashi; Ichihashi, Noriaki

    2014-01-01

    Footwear modification can beneficially alter knee loading in patients with knee osteoarthritis. This study evaluated the effect of Masai Barefoot Technology shoes on reductions in external knee moments in patients with knee osteoarthritis. Three-dimensional motion analysis was used to examine the effect of Masai Barefoot Technology versus control shoes on the knee adduction and flexion moments in 17 women (mean age, 63.6 years) with radiographically confirmed knee osteoarthritis. The lateral and anterior trunk lean values, knee flexion and adduction angles, and ground reaction force were also evaluated. The influence of the original walking pattern on the changes in knee moments with Masai Barefoot Technology shoes was evaluated. The knee flexion moment in early stance was significantly reduced while walking with the Masai Barefoot Technology shoes (0.25±0.14Nm/kgm) as compared with walking with control shoes (0.30±0.19 Nm/kgm); whereas the knee adduction moment showed no changes. Masai Barefoot Technology shoes did not increase compensatory lateral and anterior trunk lean. The degree of knee flexion moment in the original walking pattern with control shoes was correlated directly with its reduction when wearing Masai Barefoot Technology shoes by multiple linear regression analysis (adjusted R2=0.44, PBarefoot Technology shoes reduced the knee flexion moment during walking without increasing the compensatory trunk lean and may therefore reduce external knee loading in women with knee osteoarthritis.

  12. Comparison of knee gait kinematics of workers exposed to knee straining posture to those of non-knee straining workers.

    Gaudreault, Nathaly; Hagemeister, Nicola; Poitras, Stéphane; de Guise, Jacques A

    2013-06-01

    Workers exposed to knee straining postures, such as kneeling and squatting, may present modifications in knee gait kinematics that can make them vulnerable to osteoarthritis. In this study, knee kinematics of workers exposed to occupational knee straining postures (KS workers) were compared to those of non-knee straining (non-KS) workers. Eighteen KS workers and 20 non-KS workers participated in the study. Three-dimensional gait kinematic data were recorded at the knee using an electromagnetic motion tracking system. The following parameters were extracted from flexion/extension, adduction/abduction and internal/external rotation angle data and used for group comparisons: knee angle at initial foot contact, peak angles, minimal angles and angle range during the entire gait cycle. Group comparisons were performed with Student t-tests. In the sagittal plane, KS workers had a greater knee flexion angle at initial foot contact, a lower peak knee flexion angle during the swing phase and a lower angle range than non-KS workers (p<0.05). In the frontal plane, all parameters indicated that KS workers had their knees more adducted than non-KS workers. External/internal rotation range was greater for KS workers. This study provides new knowledge on work related to KS postures and knee kinematics. The results support the concept that KS workers might exhibit knee kinematics that are different from those of non-KS workers.

  13. A triboelectric motion sensor in wearable body sensor network for human activity recognition.

    Hui Huang; Xian Li; Ye Sun

    2016-08-01

    The goal of this study is to design a novel triboelectric motion sensor in wearable body sensor network for human activity recognition. Physical activity recognition is widely used in well-being management, medical diagnosis and rehabilitation. Other than traditional accelerometers, we design a novel wearable sensor system based on triboelectrification. The triboelectric motion sensor can be easily attached to human body and collect motion signals caused by physical activities. The experiments are conducted to collect five common activity data: sitting and standing, walking, climbing upstairs, downstairs, and running. The k-Nearest Neighbor (kNN) clustering algorithm is adopted to recognize these activities and validate the feasibility of this new approach. The results show that our system can perform physical activity recognition with a successful rate over 80% for walking, sitting and standing. The triboelectric structure can also be used as an energy harvester for motion harvesting due to its high output voltage in random low-frequency motion.

  14. Knee-Extension Training with a Single-Joint Hybrid Assistive Limb during the Early Postoperative Period after Total Knee Arthroplasty in a Patient with Osteoarthritis

    Sugaya, Hisashi; Kubota, Shigeki; Onishi, Mio; Kanamori, Akihiro; Sankai, Yoshiyuki; Yamazaki, Masashi

    2016-01-01

    The knee range of motion is an important outcome of total knee arthroplasty (TKA). According to previous studies, the knee range of motion temporarily decreases for approximately 1 month after TKA due to postoperative pain and quadriceps dysfunction following surgical invasion into the knee extensor mechanism. We describe our experience with a knee-extension training program based on a single-joint hybrid assistive limb (HAL-SJ, Cyberdyne Inc., Tsukuba, Japan) during the acute recovery phase after TKA. HAL-SJ is a wearable robot suit that facilitates the voluntary control of knee joint motion. A 76-year-old man underwent HAL-SJ-based knee-extension training, which enabled him to perform knee function training during the acute phase after TKA without causing increased pain. Thus, he regained the ability to fully extend his knee postoperatively. HAL-SJ-based knee-extension training can be used as a novel post-TKA rehabilitation modality.

  15. Abdominal compliance, parasternal activation, and chest wall motion.

    Cala, S J; Edyvean, J; Engel, L A

    1993-03-01

    We measured abdominal compliance (Cab) and rib cage displacement (delta Vrc) relative to abdominal displacement (delta Vab) during relaxation and tidal breathing in upright (U) and supine (S) postures in five normal subjects. In S, an abdominal binder was used to decrease Cab in two to five increments. We also measured the electrical activity of the parasternal muscle (EMGps) with the use of fine-wire intramuscular electrodes during CO2 rebreathing in U and in supine unbound (SU) and supine bound (SB) postures. During maximum binding (SB2), Cab decreased to 39 +/- 7% of the SU value (P = 0.01), matching Cab in U (P = 0.16). In the SB condition, the ratio of tidal delta Vrc/delta Vab to relaxation delta Vrc/delta Vab increased as Cab decreased, matching the data in U. For the group, this ratio decreased during SU to 47 +/- 10% (P = 0.02) but increased during SB2 to 86 +/- 7% (P = 0.18) of the value in U. During CO2 rebreathing, EMGps increased linearly with tidal volume (r > 0.727, P < 0.01). However, at any given tidal volume, the SU and SB2 EMGps were not significantly different (P = 0.12), and both were less than that in U (P < 0.02). The results suggest that the differences in chest wall motion between U and S may be due to the difference in Cab and not to different patterns of respiratory muscle recruitment. The mechanism may relate to changes in mechanical coupling between the diaphragm and the rib cage.

  16. Active Brownian motion of an asymmetric rigid particle

    Mammadov, Gulmammad

    2012-01-01

    Individual movements of a rod-like self-propelled particle on a flat substrate are quantified. Biological systems that fit into this description may be the Gram-negative delta-proteobacterium Myxococcus xanthus, Gram-negative bacterium Escherichia coli, and Mitochondria. There are also non-living analogues such as vibrated polar granulates and self-driven anisotropic colloidal particles. For that we study the Brownian motion of an asymmetric rod-like rigid particle self-propelled at a fixed speed along its long axis in two dimensions. The motion of such a particle in a uniform external potential field is also considered. The theoretical model presented here is anticipated to better describe individual cell motion as well as intracellular transport in 2D than previous models.

  17. Relação entre altura da patela e amplitude de movimentos após a artroplastia total do joelho Relationship between patellar height and range of motion after total knee arthroplasty

    Lúcio Honório de Carvalho Júnior

    2011-01-01

    Full Text Available OBJETIVO: Avaliar se após a artroplastia total do joelho existe correlação entre a altura da patela e a amplitude de movimento (ADM alcançada pelo paciente após seis meses de pós-operatório. MÉTODOS: Foram avaliados 45 pacientes submetidos a artroplastia total do joelho, todos com, no mínimo, 12 meses de pós-operatório, totalizando 54 joelhos. Sob fluoroscopia, todos os joelhos tiveram suas amplitudes de movimentos (ADM máximas e mínimas registradas, bem como a altura da patela pelo índice de Blackburne e Peel. Foram avaliadas as duas correlações possíveis: relação entre altura da patela e ADM e altura da patela e a variação de ADM entre o pré e o pós-operatório. RESULTADOS: Foi observada correlação entre altura da patela e ADM no pós-operatório (p = 0,04. Não foi observada correlação entre altura da patela e variação de ADM (p = 0,182. CONCLUSÃO: No pós-operatório da artroplastia total do joelho, quanto mais baixa a patela, pior a ADM.OBJECTIVE: To evaluate whether, after total knee arthroplasty, there is any correlation between patellar height and range of motion (ROM achieved by patients six months after the operation. METHODS: Forty-five patients who underwent total knee arthroplasty were assessed at least 12 months after the operation (total of 54 knees. The maximum and minimum ROM of all the knees was recorded under fluoroscopy, along with patellar height according to the Blackburne and Peel ratio. Two possible correlations were evaluated: patellar height and ROM; and patellar height and ROM variation from before to after the operation. RESULTS: A correlation was found between patellar height and postoperative ROM (p = 0.04. There was no correlation between patellar height and ROM variation (p = 0.182. CONCLUSION: After total knee arthroplasty, the lower the patella is, the worse the ROM is.

  18. Habitual Physical Activity After Total Knee Replacement : analysis in 830 patients and comparison with a sex-and age-matched normative population (vol 92, pg 1109, 2012)

    Kersten, Roel F. M. R.; Stevens, Martin; van Raay, Jos J. A. M.; Bulstra, Sjoerd K.; van den Akker-Scheek, Inge

    2012-01-01

    Background. Previous studies on physical activity after total knee arthroplasty (TKA) concentrated mainly on a return to sports activities. Objective. The objectives of this study were to determine the habitual physical activity behavior of people who had undergone TKA (TKA group) 1 to 5 years after

  19. Focusing on Increasing Velocity during Heavy Resistance Knee Flexion Exercise Boosts Hamstring Muscle Activity in Chronic Stroke Patients

    Jakobsen, Markus D.

    2016-01-01

    Background. Muscle strength is markedly reduced in stroke patients, which has negative implications for functional capacity and work ability. Different types of feedback during strength training exercises may alter neuromuscular activity and functional gains. Objective. To compare levels of muscle activity during conditions of blindfolding and intended high contraction speed with a normal condition of high-intensity knee flexions. Methods. Eighteen patients performed unilateral machine knee flexions with a 10-repetition maximum load. Surface electromyography (EMG) was recorded from the quadrics and hamstring muscles and normalized to maximal EMG (nEMG) of the nonparetic limb. Results. For the paretic leg, the speed condition showed higher values of muscle activity compared with the normal and blindfolded conditions for both biceps femoris and semitendinosus. Likewise, the speed condition showed higher co-contraction values compared with the normal and blindfolded conditions for the vastus lateralis. No differences were observed between exercise conditions for the nonparetic leg. Conclusion. Chronic stroke patients are capable of performing heavy resistance training with intended high speed of contraction. Focusing on speed during the concentric phase elicited higher levels of muscle activity of the hamstrings compared to normal and blindfolded conditions, which may have implications for regaining fast muscle strength in stroke survivors. PMID:27525118

  20. The effects of a single game of rugby on active cervical range of motion.

    Lark, Sally D; McCarthy, Peter W

    2009-03-01

    The cumulative effect of playing rugby over many years decreases active cervical range of motion, especially in the forwards. This in itself should influence long-term neck care; however, it leaves the important question of how noticeable the acute effects of active cervical range of motion are following a single game. The active cervical range of motion was measured in 21 elite rugby players (mean age 24.4 +/- 4.3 years; average professional career of 7 +/- 3.4 years) before and after a single game of rugby at the start of the season. The active cervical range of motion was recorded in flexion, extension, left and right side flexion, plus left and right rotation using a cervical range of motion device. The results show generally decreased active cervical range of motion from before to after a game independent of position played. Rugby backs had significantly (P cervical range of motion in flexion, while forwards were affected in extension and left lateral flexion (P cervical range of motion), and the affected neck movement appears to be related to the role of positional play. The authors suggest that neck training and muscle damage repair should be an important part of a rugby player's post-game recovery to limit the reduction in functional capacity.

  1. Will 'Unloading' Shoes Help Your Arthritic Knees?

    ... anti-inflammatory medications may also help, as might physical therapy designed to improve flexibility and motion range. In severe cases, patients undergo invasive knee surgery ranging from joint-lining removal to partial or ...

  2. The effects of Juchumseogi and Juchumseo Jireugi motions of taekwondo on muscle activation of paraspinal muscles.

    Baek, Jongmyeng; Lee, Jaeseok; Kim, Jonghyun; Kim, Jeonghun; Han, Dongwook; Byun, Sunghak

    2015-09-01

    [Purpose] The purpose of this study is to examine the effects of Juchumseogi and Juchumseo Jireugi motions on muscle activation of the paraspinal muscles. [Subjects] The subjects of this study were 20 healthy male students who listened to an explanation of the study methods and the purpose of the experiment, and agreed to participate in the study. [Methods] Muscle activation measurements of the paraspinal muscles at C3, T7, and L3 were taken while standing still and while performing Juchumseogi and Juchumseo Jireugi movements. The Juchumseogi and Juchumseo Jireugi motions were performed 3 times, and its mean value was used for analysis. [Results] The right and left muscle activation of paraspinal muscles induced by Juchumseogi and Juchumseo Jireugi motions in C3 and T7 were significantly higher than those induced by just standing. Muscle activation of paraspinal muscles induced by Juchumseo Jireugi motions in C3, T7, and L3 were significantly higher than those induced by Juchumseogi alone. The right and left muscle activation of paraspinal muscles induced by Juchumseo Jireugi motion in C3, T7, and L3 were significantly higher than those induced by standing and Juchumseogi alone. [Conclusion] This study demonstrated that Juchumseogi and Juchumseo Jireugi motions of Taekwondo could increase muscle activation of paraspinal muscles, and Juchumseo Jireugi motions were more effective for enhancing muscle activation of paraspinal muscles.

  3. Quantitative MR characterization of disease activity in the knee in children with juvenile idiopathic arthritis: a longitudinal pilot study

    Workie, Dagnachew W. [University of Cincinnati, Department of Physics, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Graham, T.B. [Cincinnati Children' s Hospital Medical Center, Division of Rheumatology, Cincinnati, OH (United States); Laor, Tal; Racadio, Judy M. [Cincinnati Children' s Hospital Medical Center, Department of Pediatrics, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States); Rajagopal, Akila; O' Brien, Kendall J.; Bommer, Wendy A. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Shire, Norah J. [University of Cincinnati, Division of Epidemiology and Biostatistics, Cincinnati, OH (United States); University of Cincinnati, Division of Digestive Diseases, Cincinnati, OH (United States); Dardzinski, Bernard J. [Cincinnati Children' s Hospital Medical Center, Imaging Research Center, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Pediatrics, Cincinnati, OH (United States); Cincinnati Children' s Hospital Medical Center, Department of Radiology, Cincinnati, OH (United States)

    2007-06-15

    The development of a quantifiable and noninvasive method of monitoring disease activity and response to therapy is vital for arthritis management. The purpose of this study was to investigate the utility of quantitative dynamic contrast-enhanced MRI (DCE-MRI) based on pharmacokinetic (PK) modeling to evaluate disease activity in the knee and correlate the results with the clinical assessment in children with juvenile idiopathic arthritis (JIA). A group of 17 children with JIA underwent longitudinal clinical and laboratory assessment and DCE-MRI of the knee at enrollment, 3 months, and 12 months. A PK model was employed using MRI signal enhancement data to give three parameters, K{sup trans} ' (min{sup -1}), k{sub ep} (min{sup -1}), and V{sub p} ' and to calculate synovial volume. The PK parameters, synovial volumes, and clinical and laboratory assessments in most children were significantly decreased (P < 0.05) at 12 months when compared to the enrollment values. There was excellent correlation between the PK and synovial volume and the clinical and laboratory assessments. Differences in MR and clinical parameter values in individual subjects illustrate persistent synovitis when in clinical remission. A decrease in PK parameter values obtained from DCE-MRI in children with JIA likely reflects diminution of disease activity. This technique may be used as an objective follow-up measure of therapeutic efficacy in patients with JIA. MR imaging can detect persistent synovitis in patients considered to be in clinical remission. (orig.)

  4. A group-mediated physical activity intervention in older knee osteoarthritis patients: effects on social cognitive outcomes.

    Focht, Brian C; Garver, Matthew J; Lucas, Alexander R; Devor, Steven T; Emery, Charles F; Hackshaw, Kevin V; Fairman, Ciaran M; Bowman, Jessica; Rejeski, W Jack

    2017-01-20

    The objective of the present study was to compare a group-mediated cognitive behavioral (GMCB) physical activity intervention with traditional exercise therapy (TRAD) upon select social cognitive outcomes in sedentary knee osteoarthritis (knee OA) patients. A total of 80 patients (mean age = 63.5 years; 84% women) were recruited using clinic and community-based strategies to a 12-month, single-blind, two-arm, randomized controlled trial. Mobility-related self-efficacy, self-regulatory self-efficacy (SRSE), and satisfaction with physical function (SPF) were assessed at baseline, 3, and 12 months. Results of intent-to-treat 2 (Treatment: GMCB and TRAD) × 2 (Time: 3 and 12 month) analyses of covariance yielded significantly greater increases in SRSE and SPF (P physical activity and mobility at 3 and 12-months. The GMCB intervention yielded more favorable effects on important social cognitive outcomes than TRAD; these effects were related to improvements in physical activity and mobility.

  5. Measurement of perioperative flexion-extension mechanics of the knee joint.

    Giori, N J; Giori, K L; Woolson, S T; Goodman, S B; Lannin, J V; Schurman, D J

    2001-10-01

    Perioperative knee mechanics currently are evaluated Perioperative knee mechanics currently are evaluated by measuring range of motion. This is an incomplete measurement, however, because the torque applied to achieve the motion is not measured. We hypothesized that a custom goniometer and force transducer could measure the torque required to passively flex a knee through its full range of motion. This measurement was done in the operating room immediately before and after surgery in 20 knees having total knee arthroplasty and 9 having surgery on another limb. Surgery changed the mechanics of 8 knees, whereas unoperated knees remained unchanged. This measurement technique is safe, easy, and repeatable. It improves on the current standard of perioperative knee measurement and can be applied to investigate the effects of surgery and rehabilitation on ultimate knee motion.

  6. Application of computational lower extremity model to investigate different muscle activities and joint force patterns in knee osteoarthritis patients during walking.

    Nha, Kyung Wook; Dorj, Ariunzaya; Feng, Jun; Shin, Jun Ho; Kim, Jong In; Kwon, Jae Ho; Kim, Kyungsoo; Kim, Yoon Hyuk

    2013-01-01

    Many experimental and computational studies have reported that osteoarthritis in the knee joint affects knee biomechanics, including joint kinematics, joint contact forces, and muscle activities, due to functional restriction and disability. In this study, differences in muscle activities and joint force patterns between knee osteoarthritis (OA) patients and normal subjects during walking were investigated using the inverse dynamic analysis with a lower extremity musculoskeletal model. Extensor/flexor muscle activations and torque ratios and the joint contact forces were compared between the OA and normal groups. The OA patients had higher extensor muscle forces and lateral component of the knee joint force than normal subjects as well as force and torque ratios of extensor and flexor muscles, while the other parameters had little differences. The results explained that OA patients increased the level of antagonistic cocontraction and the adduction moment on the knee joint. The presented findings and technologies provide insight into biomechanical changes in OA patients and can also be used to evaluate the postoperative functional outcomes of the OA treatments.

  7. Application of Computational Lower Extremity Model to Investigate Different Muscle Activities and Joint Force Patterns in Knee Osteoarthritis Patients during Walking

    Kyung Wook Nha

    2013-01-01

    Full Text Available Many experimental and computational studies have reported that osteoarthritis in the knee joint affects knee biomechanics, including joint kinematics, joint contact forces, and muscle activities, due to functional restriction and disability. In this study, differences in muscle activities and joint force patterns between knee osteoarthritis (OA patients and normal subjects during walking were investigated using the inverse dynamic analysis with a lower extremity musculoskeletal model. Extensor/flexor muscle activations and torque ratios and the joint contact forces were compared between the OA and normal groups. The OA patients had higher extensor muscle forces and lateral component of the knee joint force than normal subjects as well as force and torque ratios of extensor and flexor muscles, while the other parameters had little differences. The results explained that OA patients increased the level of antagonistic cocontraction and the adduction moment on the knee joint. The presented findings and technologies provide insight into biomechanical changes in OA patients and can also be used to evaluate the postoperative functional outcomes of the OA treatments.

  8. Effect of anterior cruciate ligament reconstruction on biomechanical features of knee in level walking: a meta-analysis

    SHI Dong-liang; WANG Yu-bin; AI Zi-sheng

    2010-01-01

    Background The anterior cruciate ligament (ACL) is one of the most commonly injured knee ligaments. Even following ACL reconstruction, significant articular cartilage degeneration can be observed and most patients suffer from premature osteoarthritis. Articular cartilage degeneration and osteoarthritis development after ACL injury are regarded as progressive process that are affected by cyclic loading during frequently performed low-intensity daily activities. The purpose of this study was to perform a meta analysis on studies assessing the effects of ACL reconstruction on kinematics, kinetics and proprioception of knee during level walking.Methods This meta analysis was conducted according to the methodological guidelines outlined by the Cochrane Collaboration. An electronic search of the literature was performed and all trials published between January 1966 and July 2010 comparing gait and proprioception of a reconstructed-ACL group with an intact-ACL group were pooled for this review. Thirteen studies were included in the final meta analysis.Results There was no significant difference in step length, walking speed, maximum knee flexion angle during loading response, joint position sense and threshold to detect passive motion between the reconstructed-ACL group and the intact-ACL group (P >0.05). However, there was a significant difference in peak knee flexion angle, maximum angular knee flexion excursion during stance, peak knee flexion moment during walking and maximum external tibial rotation angle throughout the gait cycle between the reconstructed-ACL group and the intact-ACL group (P <0.05).Conclusions Step length, walking speed, maximum knee flexion angle during loading response, joint position sense and threshold to detect passive motion usually observed with ACL deficiency were restored after the ACL reconstruction and rehabilitation, but no significant improvements were observed for peak knee flexion angle, maximum angular knee flexion excursion

  9. Total Knee Arthroplasty Designed to Accommodate the Presence or Absence of the Posterior Cruciate Ligament

    Melinda K. Harman

    2014-01-01

    Full Text Available Evidence for selecting the same total knee arthroplasty prosthesis whether the posterior cruciate ligament (PCL is retained or resected is rarely documented. This study reports prospective midterm clinical, radiographic, and functional outcomes of a fixed-bearing design implanted using two different surgical techniques. The PCL was completely retained in 116 knees and completely resected in 43 knees. For the entire cohort, clinical knee (96±7 and function (92±13 scores and radiographic outcomes were good to excellent for 84% of patients after 5–10 years in vivo. Range of motion averaged 124˚±9˚, with 126 knees exhibiting ≥120° flexion. Small differences in average knee flexion and function scores were noted, with the PCL-resected group exhibiting an average of 5° more flexion but an average function score that was 7 points lower compared to the PCL-retained group. Fluoroscopic analysis of 33 knees revealed stable tibiofemoral translations. This study demonstrates that a TKA articular design with progressive congruency in the lateral compartment can provide for femoral condyle rollback in maximal flexion activities and achieve good clinical and functional performance in patients with PCL-retained and PCL-resected TKA. This TKA design proved suitable for use with either surgical technique, providing surgeons with the choice of maintaining or sacrificing the PCL.

  10. Sagittal knee joint kinematics and energetics in response to different landing heights and techniques.

    Yeow, C H; Lee, P V S; Goh, J C H

    2010-03-01

    Single-leg and double-leg landing techniques are common athletic maneuvers typically performed from various landing heights during intensive sports activities. However, it is still unclear how the knee joint responds in terms of kinematics and energetics to the combined effects of different landing heights and techniques. We hypothesized that the knee displays greater flexion angles and angular velocities, joint power and work in response to the larger peak ground reaction force from 0.6-m height, compared to 0.3-m height. We further hypothesized that the knee exhibits elevated flexion angles and angular velocities, joint power and work during double-leg landing, relative to single-leg landing. Ground reaction force, knee joint kinematics and energetics data were obtained from 10 subjects performing single-leg and double-leg landing from 0.3-m to 0.6-m heights, using motion-capture system and force-plates. Higher peak ground reaction force (pheight. We found greater knee flexion angles and angular velocities (pheight. Elevated knee joint power and work were noted (pheight. The knee joint is able to respond more effectively in terms of kinematics and energetics to a larger landing impact from an elevated height during double-leg landing, compared to single-leg landing. This allows better shock absorption and thus minimizes the risk of sustaining lower extremity injuries.

  11. Influence of Active Manipulation of an Object on Visual Motion Perception

    Kazumichi Matsumiya

    2011-10-01

    Full Text Available When we manipulate an object by hand, the movements of the object are produced with the visual and haptic movements of our hands. Studies of multimodal perception show the interaction between touch and vision in visual motion perception(1,2. The influence of touch on visual motion perception is shown by the fact that adaptation to tactile motion across the observer's hand induces a visual motion aftereffect, which is a visual illusion in which exposure to a moving visual pattern makes a subsequently viewed stationary visual pattern appear to move in the opposite direction(2. This visuo-tactile interaction plays an important role in skillful manipulation(3. However, it is not clear how haptic information influences visual motion perception. We measured the strength of a visual motion aftereffect after visuo-haptic adaptation to a windmill rotated by observers. We found that the visual motion aftereffect was enhanced when observers actively rotated the windmill. The motion aftereffect was not enhanced when the observer's hand was passively moved. Our results suggest the presence of a visual motion system that is linked to the intended haptic movements.

  12. Runner's Knee

    ... Over the summer he bought a pair of running shoes and took up jogging. He started with ... bending the knee — when walking, kneeling, squatting, or running, for example. Walking or running downhill or even ...

  13. Physical Activity Recognition Based on Motion in Images Acquired by a Wearable Camera.

    Zhang, Hong; Li, Lu; Jia, Wenyan; Fernstrom, John D; Sclabassi, Robert J; Mao, Zhi-Hong; Sun, Mingui

    2011-06-01

    A new technique to extract and evaluate physical activity patterns from image sequences captured by a wearable camera is presented in this paper. Unlike standard activity recognition schemes, the video data captured by our device do not include the wearer him/herself. The physical activity of the wearer, such as walking or exercising, is analyzed indirectly through the camera motion extracted from the acquired video frames. Two key tasks, pixel correspondence identification and motion feature extraction, are studied to recognize activity patterns. We utilize a multiscale approach to identify pixel correspondences. When compared with the existing methods such as the Good Features detector and the Speed-up Robust Feature (SURF) detector, our technique is more accurate and computationally efficient. Once the pixel correspondences are determined which define representative motion vectors, we build a set of activity pattern features based on motion statistics in each frame. Finally, the physical activity of the person wearing a camera is determined according to the global motion distribution in the video. Our algorithms are tested using different machine learning techniques such as the K-Nearest Neighbor (KNN), Naive Bayesian and Support Vector Machine (SVM). The results show that many types of physical activities can be recognized from field acquired real-world video. Our results also indicate that, with a design of specific motion features in the input vectors, different classifiers can be used successfully with similar performances.

  14. Knee Injuries and Disorders

    Your knee joint is made up of bone, cartilage, ligaments and fluid. Muscles and tendons help the knee joint move. When any of these structures is hurt or diseased, you have knee problems. Knee problems can cause pain and difficulty ...

  15. High knee valgus in female subjects does not yield higher knee translations during drop landings: a biplane fluoroscopic study.

    Torry, Michael R; Shelburne, Kevin B; Myers, Casey; Giphart, J Erik; Pennington, W Wesley; Krong, Jacob P; Peterson, Daniel S; Steadman, J Richard; Woo, Savio L-Y

    2013-02-01

    The goal of this study was to determine the effects of peak knee valgus angle and peak knee abductor moment on the anterior, medial, and lateral tibial translations (ATT, MTT, LTT) in the "at risk" female knee during drop landing. Fifteen female subjects performed drop landings from 40 cm. Three-dimension knee motion was simultaneously recorded using a high speed, biplane fluoroscopy system, and a video-based motion analysis system. Valgus knee angles and knee abduction moments were stratified into low, intermediate, and high groups and peak ATT, MTT, and LTT were compared between these groups with ANOVA (α = 0.05). Significant differences were observed between stratified groups in peak knee valgus angle (p < 0.0001) and peak knee abduction moment (p < 0.0001). However, no corresponding differences in peak ATT, LTT, and MTT between groups exhibiting low to high-peak knee valgus angles (ATT: p = 0.80; LTT: p = 0.25; MTT: p = 0.72); or, in peak ATT (p = 0.61), LTT (p = 0.26) and MTT (p = 0.96) translations when stratified according to low to high knee abduction moments, were found. We conclude that the healthy female knee is tightly regulated with regard to translations even when motion analysis derived knee valgus angles and abduction moments are high.

  16. The Clinical Effect of Platelet Rich Plasma Prepared Through Different Activation Methods on Patients with Knee Osteoarthritis

    Nevres Aydogan

    2016-11-01

    Full Text Available Aim: Intra-articular application of platelet rich plasma (PRP can be an alternative treatment method for knee osteoarthritis. The objective of this study was to compare the activation methods of platelet rich plasma before intra-articular application. Material and Method: A total 51 patients (76 knees was randomly selected into two groups. In group 1, activation of PRP was managed by adding calcium chloride (CaCl. In group 2, activation of PRP was managed by keeping the solution at -70° degrees for 24 hours after preparation and immersed in water at 37oC for a period of 5 minutes for complete dissolution. Then PRP was applied. The patients were assessed with VAS and WOMAC pain scores both baseline and after 2nd, 6th and 12th months of the treatment. Results: VAS and WOMAC pain scores were significantly higher at baseline compared to the results obtained at the 2nd, 6th and 12th months (p=0.06. Following 2nd, 6th and 12th months a gradual downward tendency was seen in both scores, even though no significant difference was found between the groups after 2nd, 6th and 12th months. Discussion: Patients received some clinical benefits from both activation methods. There is no significant difference between activating PRP by CaCl or -70°C which compared in terms of clinical benefits. Therefore, blood storage at -70ºC may be preferred primary due to no need for additional material such as CaCl.

  17. Multiple Ligament Knee Injury: Complications

    Manske, Robert C; Hosseinzadeh, Pooya; Giangarra, Charles E.

    2008-01-01

    Non-operative and operative complications are common following multiple ligament knee injuries. This article will describe common complications seen by the surgeon and physical therapist following this complex injury. Complications include fractures, infections, vascular and neurologic complications following injury and surgery, compartment syndrome, complex regional pain syndrome, deep venous thrombosis, loss of motion and persistent laxity issues. A brief description of these complications ...

  18. Objective clinical performance outcome of total knee prostheses. A study of mobile bearing knees using fluoroscopy, electromyography and roentgenstereophotogrammetry

    Garling, Eric Harald

    2008-01-01

    The aim of the thesis was to to assess with accurate and objective methods the function and fixation of total knee prostheses with special emphasis on mobile bearing total knee designs. The mobile bearing of a rotating platform design showed limited motion or no motion during a step-up task thereby

  19. Primary osteosynthesis augmented with autologous bone graft with total knee arthroplasty in patients with stress fractures of medial femoral condyle with knee osteoarthritis: a cost effective approach

    Vikram Indrajit Shah

    2016-06-01

    Results: Mean follow-up was 7.0 years. All patients showed statistically significant improvement in their WOMAC total scores (p <0.05. Stress fractures united with good knee alignment. All patients had recovered full range of motion with no pain at the time of final follow-up. No adverse events were noted in any of the patient treated. Conclusions: The present approach is a successful procedure for the elderly population with an arthritic knee with stress fracture of medial femoral condyle. Return to pre-morbid level of functional activity occurs very swiftly. [Int J Res Med Sci 2016; 4(6.000: 2408-2412

  20. The visual perception of natural motion: abnormal task-related neural activity in DYT1 dystonia.

    Sako, Wataru; Fujita, Koji; Vo, An; Rucker, Janet C; Rizzo, John-Ross; Niethammer, Martin; Carbon, Maren; Bressman, Susan B; Uluğ, Aziz M; Eidelberg, David

    2015-12-01

    Although primary dystonia is defined by its characteristic motor manifestations, non-motor signs and symptoms have increasingly been recognized in this disorder. Recent neuroimaging studies have related the motor features of primary dystonia to connectivity changes in cerebello-thalamo-cortical pathways. It is not known, however, whether the non-motor manifestations of the disorder are associated with similar circuit abnormalities. To explore this possibility, we used functional magnetic resonance imaging to study primary dystonia and healthy volunteer subjects while they performed a motion perception task in which elliptical target trajectories were visually tracked on a computer screen. Prior functional magnetic resonance imaging studies of healthy subjects performing this task have revealed selective activation of motor regions during the perception of 'natural' versus 'unnatural' motion (defined respectively as trajectories with kinematic properties that either comply with or violate the two-thirds power law of motion). Several regions with significant connectivity changes in primary dystonia were situated in proximity to normal motion perception pathways, suggesting that abnormalities of these circuits may also be present in this disorder. To determine whether activation responses to natural versus unnatural motion in primary dystonia differ from normal, we used functional magnetic resonance imaging to study 10 DYT1 dystonia and 10 healthy control subjects at rest and during the perception of 'natural' and 'unnatural' motion. Both groups exhibited significant activation changes across perceptual conditions in the cerebellum, pons, and subthalamic nucleus. The two groups differed, however, in their responses to 'natural' versus 'unnatural' motion in these regions. In healthy subjects, regional activation was greater during the perception of natural (versus unnatural) motion (P perception of unnatural (versus natural) motion (P perception is disrupted in DYT1

  1. Knee joint laxity and neuromuscular characteristics of male and female soccer and basketball players.

    Rozzi, S L; Lephart, S M; Gear, W S; Fu, F H

    1999-01-01

    Anterior cruciate ligament injuries are occurring at a higher rate in female athletes compared with their male counterparts. Research in the area of anterior cruciate ligament injury has increasingly focused on the role of joint proprioception and muscle activity in promoting knee joint stability. We measured knee joint laxity, joint kinesthesia, lower extremity balance, the amount of time required to generate peak torque of the knee flexor and extensor musculature, and electromyographically assessed muscle activity in 34 healthy, collegiate-level athletes (average age, 19.6 +/- 1.5 years) who played soccer or basketball or both. Independent t-tests were used to determine significant sex differences. Results revealed that women inherently possess significantly greater knee joint laxity values, demonstrate a significantly longer time to detect the knee joint motion moving into extension, possess significantly superior single-legged balance ability, and produce significantly greater electromyographic peak amplitude and area of the lateral hamstring muscle subsequent to landing a jump. The excessive joint laxity of women appears to contribute to diminished joint proprioception, rendering the knee less sensitive to potentially damaging forces and possibly at risk for injury. Unable to rely on ligamentous structures, healthy female athletes appear to have adopted compensatory mechanisms of increased hamstring activity to achieve functional joint stabilization.

  2. Arthroscopy of the knee without pathological findings.

    Schlepckow, P; Weber, M; Hempel, K

    1994-01-01

    From 1983 to 1990, 82 knee arthroscopies (8.2%) carried out in our patients found nothing pathological. Sixty-four percent of these patients were active in sports, but trauma was noted in 32% of the cases only. Football and other ball games, skiing, and track and field athletics were the main causes. Twenty-six percent of the patients had undergone previous surgery in the affected knee. At a mean of 4.6 years postoperatively, clinical and radiological re-assessment was conducted so as to compare our pre- and intraoperative findings with the further course of events. We found that 48.2% of the patients were symptom-free after the diagnostic arthroscopy, 37.5% had persistent discomfort and 14.3% had a recurrence of discomfort after 6 months to 2 years. The objective measurement score (Zarins Rowe score), at 47.5 out of 50 points, was better than the subjective score, at 40 out of 50 points. Our diagnoses had to be changed retrospectively: meniscal lesions were diagnosed too frequently, while chondropathia patellae and instability were often missed. Additionally, complaints could be related to abnormal axis, limited range of motion of the hip or knee, leg length inequality and hypermobility. Being unable to verify a presumed intra-articular lesion arthroscopically is frustrating for both doctor and patient. Our data suggest that meniscal signs should be looked at more critically and emphasise the need for a complete evaluation of the whole locomotor system.

  3. Does knee awareness differ between different knee arthroplasty prostheses?

    Thomsen, Morten G; Latifi, Roshan; Kallemose, Thomas

    2016-01-01

    BACKGROUND: Low knee awareness after Total Knee Arthroplasty (TKA) has become the ultimate goal in trying to achieve a natural feeling knee that meet patient expectations. To accommodate this manufacturers of TKAs have developed new prosthetic designs that potentially could give patients a more...... natural feeling knee during activities. The purpose af this study was to compare the Forgotten Joint Score (FJS) and Oxford Knee Score (OKS) of patients treated with a previous generation standard Cruciate Retaining (CR) TKA to the scores obtained by patients treated with a newer generation CR TKA...... or a mobile bearing CR TKA. METHODS: We identified all patients receiving a new generation CR TKA or mobile bearing TKA at our institution between 2010 and 2012. These were matched to a population of patients receiving a standard CR TKA regarding age, gender, year of surgery, Kellgren-Lawrence (KL) grade...

  4. Differences in evoked potentials during the active processing of sound location and motion.

    Richter, Nicole; Schröger, Erich; Rübsamen, Rudolf

    2013-06-01

    Difference in the processing of motion and static sounds in the human cortex was studied by electroencephalography with subjects performing an active discrimination task. Sound bursts were presented in the acoustic free-field between 47° to the left and 47° to the right under three different stimulus conditions: (i) static, (ii) leftward motion, and (iii) rightward motion. In an active oddball design, subject was asked to detect target stimuli which were randomly embedded within a stream of frequently occurring non-target events (i.e. 'standards') and rare non-target stimuli (i.e. 'deviants'). The respective acoustic stimuli were presented in blocks with each stimulus type presented in either of three stimulus conditions: as target, as non-target, or as standard. The analysis focussed on the event related potentials evoked by the different stimulus types under the respective standard condition. Same as in previous studies, all three different acoustic stimuli elicited the obligatory P1/N1/P2 complex in the range of 50-200 ms. However, comparisons of ERPs elicited by static stimuli and both kinds of motion stimuli yielded differences as early as ~100 ms after stimulus-onset, i.e. at the level of the exogenous N1 and P2 components. Differences in signal amplitudes were also found in a time window 300-400 ms ('d300-400 ms' component in 'motion-minus-static' difference wave). For motion stimuli, the N1 amplitudes were larger over the hemisphere contralateral to the origin of motion, while for static stimuli N1 amplitudes over both hemispheres were in the same range. Contrary to the N1 component, the ERP in the 'd300-400 ms' time period showed stronger responses over the hemisphere contralateral to motion termination, with the static stimuli again yielding equal bilateral amplitudes. For the P2 component a motion-specific effect with larger signal amplitudes over the left hemisphere was found compared to static stimuli. The presently documented N1 components comply

  5. Move with Science: Energy, Force, & Motion. An Activities-Based Teacher's Guide.

    Beven, Roy Q.

    The secondary school level activities contained in this book use the subject of transportation to teach the basic concepts of physics and several areas of human biology. The material is organized into sections including curriculum design, activities, background readings, and resources. Activities focus on such topics as notions of motion stability…

  6. High-intensity preoperative training improves physical and functional recovery in the early post-operative periods after total knee arthroplasty

    Calatayud, Joaquin; Casaña, Jose; Ezzatvar, Yasmin;

    2017-01-01

    -four subjects (7 men, 37 women) scheduled for unilateral TKA for osteoarthritis (OA) during 2014 participated in this randomized controlled trial. Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Physical Functioning Scale of the Short Form-36 questionnaire (SF-36), a 10-cm visual...... analogue scale (VAS), isometric knee flexion, isometric knee extension, isometric hip abduction, active knee range of motion and functional tasks (Timed Up and Go test and Stair ascent-descent test) were assessed at 8 weeks before surgery (T1), after 8 weeks of training (T2), 1 month after TKA (T3...

  7. Adaptations in muscular activation of the knee extensor muscles with strength training in young and older adults.

    Knight, C A; Kamen, G

    2001-12-01

    The purpose of this study was to compare the extent of muscular activation during maximal voluntary knee extension contractions in old and young individuals and to examine the effects of resistance training on muscular activation in each group. The interpolated twitch technique was used to estimate muscular activation during two pre-training baseline tests, and after two and six weeks of resistance training. Throughout the study, the older group was 30% less strong than the young group (p=0.02). The training protocol was effective in both groups with overall isometric strength gains of 30 and 36% in the older (p=0.01) and young (pmuscular activation between groups (p=0.3) did not explain the large disparity in strength. Muscular activation increased by 2% in both groups throughout training (pmuscular strength in the older group, muscular activation was greater than 95% of maximum and appears to be equal in both young and older individuals. Both groups demonstrated similar but small increases in muscular activation throughout training.

  8. The association between symptoms, pain coping strategies, and physical activity among people with symptomatic knee and hip osteoarthritis

    Susan L Murphy

    2012-09-01

    Full Text Available Effective use of coping strategies by people with chronic pain conditions is associated with better functioning and adjustment to chronic disease. Although the effects of coping on pain have been well studied, less is known about how specific coping strategies relate to actual physical activity patterns in daily life. The purpose of this study was to evaluate how different coping strategies relate to symptoms and physical activity patterns in a sample of adults with knee and hip osteoarthritis (N = 44. Physical activity was assessed by wrist-worn accelerometry; coping strategy use was assessed by the Chronic Pain Coping Inventory. We hypothesized that the use of coping strategies that reflect approach behaviors (e.g., Task Persistence, would be associated with higher average levels of physical activity, whereas avoidance coping behaviors (e.g., Resting, Asking for Assistance, Guarding and Pacing would be associated with lower average levels of physical activity. We also evaluated whether coping strategies moderated the association between momentary symptoms (pain and fatigue and activity. We hypothesized that higher levels of approach coping would be associated with a weaker association between symptoms and activity compared to lower levels of this type of coping. Multilevel modeling was used to analyze the momentary association between coping and physical activity. We found that higher body mass index, fatigue, and the use of Guarding were significantly related to lower activity levels, whereas Asking for Assistance was significantly related to higher activity levels. Only Resting moderated the association between pain and activity. Guarding, Resting, Task Persistence, and Pacing moderated the association between fatigue and activity. This study provides an initial understanding of how people with osteoarthritis cope with symptoms as they engage in daily life activities using ecological momentary assessment and objective physical activity

  9. The biomechanics and energetics of human running using an elastic knee exoskeleton.

    Elliott, Grant; Sawicki, Gregory S; Marecki, Andrew; Herr, Hugh

    2013-06-01

    While the effects of series compliance on running biomechanics are well documented, the effects of parallel compliance are known only for the simpler case of hopping. As many practical exoskeletal and orthotic designs act in parallel with the leg, it is desirable to understand the effects of such an intervention. Spring-like forces offer a natural choice of perturbation for running, as they are both biologically motivated and energetically inexpensive to implement. To this end, we investigate the hypothesis that the addition of an external elastic element at the knee during the stance phase of running results in a reduction in knee extensor activation so that total joint quasi-stiffness is maintained. An exoskeletal knee brace consisting of an elastic element engaged by a clutch is used to provide this stance phase extensor torque. Motion capture of five subjects is used to investigate the consequences of running with this device. No significant change in leg stiffness or total knee stiffness is observed due to the activation of the clutched parallel knee spring. However, this pilot data suggests differing responses between casual runners and competitive long-distance runners, whose total knee torque is increased by the device. Such a relationship between past training and effective utilization of an external force is suggestive of limitations on the applicability of assistive devices.

  10. Contrast-enhanced MRI of the knee in children unaffected by clinical arthritis compared to clinically active juvenile idiopathic arthritis patients

    Nusman, Charlotte M.; Hemke, Robert [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Benninga, Marc A.; Kindermann, Angelika [University of Amsterdam, Department of Pediatric Gastroenterology, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Schonenberg-Meinema, Dieneke; Berg, J.M. van den; Kuijpers, Taco W. [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Rossum, Marion A.J. van [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Reade, Department of Pediatric Rheumatology, Amsterdam (Netherlands); Maas, Mario [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands)

    2016-04-15

    To evaluate enhancing synovial thickness upon contrast-enhanced magnetic resonance imaging (MRI) of the knee in children unaffected by clinical arthritis compared with clinically active juvenile idiopathic arthritis (JIA) patients. A secondary objective was optimization of the scoring method based on maximizing differences on MRI between these groups. Twenty-five children without history of joint complaints nor any clinical signs of joint inflammation were age/sex-matched with 25 clinically active JIA patients with arthritis of at least one knee. Two trained radiologists, blinded for clinical status, independently evaluated location and extent of enhancing synovial thickness with the validated Juvenile Arthritis MRI Scoring system (JAMRIS) on contrast-enhanced axial fat-saturated T1-weighted MRI of the knee. Enhancing synovium (≥2 mm) was present in 13 (52 %) unaffected children. Using the total JAMRIS score for synovial thickening, no significant difference was found between unaffected children and active JIA patients (p = 0.091). Additional weighting of synovial thickening at the JIA-specific locations enabled more sensitive discrimination (p = 0.011). Mild synovial thickening is commonly present in the knee of children unaffected by clinical arthritis. The infrapatellar and cruciate ligament synovial involvement were specific for JIA, which - in a revised JAMRIS - increases the ability to discriminate between JIA and unaffected children. (orig.)

  11. Translational Optic Flow Induces Shifts in Direction of Active Forward and Backward Self-Motion

    Kenzo Sakurai

    2011-05-01

    Full Text Available Previously, we reported that when observers passively experience real linear oscillatory somatic motion while viewing orthogonal visual optic flow patterns, their perceived motion direction is intermediate to those specified by visual and vestibular information individually (Sakurai et al., 2002, ACV; 2003, ECVP; 2010, VSS; Kubodera et al., 2010, APCV. Here, we extend those studies to active somatic motion, measuring the angular shift in body direction after active body motion while viewing synchronized orthogonal optic flow. Experimental visual stimuli consisted of 1 second of translating leftward (rightward random-dots and 1 second of random noise. Control stimuli consisted of two 1-second intervals of random noise separated by a static interval. Observers viewed the stimulus for 30 seconds through a face-mounted display while actively stepping forward and backward such that their forward body movement was synchronized with the random-dot translational motion. Observers' body direction was measured before and after each trial. Translational optic flow induced shifts in body direction that were opposite to shifts in perceived direction with passive viewing in our previous reports. Observers may have compensated their body motion in response to perceived direction shifts similar to those we reported for passive viewing.

  12. The INDUS knee prosthesis - Prospective multicentric trial of a posteriorly stabilized high-flex design: 2 years follow-up

    Sancheti Kantilal

    2009-01-01

    Full Text Available Background: The anatomical and morphological differences and high-flexion daily activities in the Asian population have since ever prompted for development of customized knee replacement systems. INDUS knee system has advantages both of high-flex designs and is developed by keeping the anatomical variations of the native population in mind. The purpose of this study is to analyze the 2-year follow-up results using the INDUS prosthesis. Materials and Methods: Two hundred and ninety-seven knees in 276 patients were prospectively analyzed. There were 65 men (72 knees and 211 (225 knees women with a mean age of 64.56 years. Two hundred and forty-five knees had primary osteoarthritis, 48 knees had rheumatoid arthritis, and four knees had post-traumatic arthritis. Clinical parameters, including the Knee Society scores (knee score and function score, range of motion, post-operative anterior knee pain, and complications were recorded. Pre- and post-operative serial radiographs were analyzed for limb alignment, component positioning, and evidence of loosening. Results: The patients were followed-up for an average of 2.59 years (range, 2-3.3 years. The mean knee score and the mean function score were significantly improved from a pre-operative value of 39.4 points and 46.7 points to a post-operative value of 87 points and 86 points, respectively (P value < 0.05. Two hundred and thirty four knees had no anterior knee pain while 63 knees had mild to moderate pain, but none of the patients requested any intervention for the same. Of the 276 patients (297 knees, 79 knees had flexion above 140°, 167 had a flexion range of 130-140°, 27 had a flexion range of 100-130°, and 24 knees had a flexion < 100°, with the mean range of movement being 132.9°. Improvements in the range of movement were retained over time and a total of 205 patients (224 knees, 75.7% could squat or sit cross-legged at the final follow-up. The mean tibiofemoral angle was 8.5°± 6.9º of

  13. The Effects of Continued Rehabilitation After Primary Knee Replacement

    Radulovic, Tatjana Nozica; Lazovic, Milica; Jandric, Slavica; Bucma, Tatjana; Cvjetkovic, Dragana Dragicevic; Manojlovic, Slavko

    2016-01-01

    Introduction: Tasks of rehabilitation after arthroplasty are to provide painless joint movements, to improve the range of motion, to establish a scheme of walking, to achieve independence in activities of daily living. The aim: of the study is to determine the effects of continued rehabilitation on the range of the knee motion and reducing the swelling after total knee replacement. Methods: The study was conducted from 2011 to 2013 and included 140 patients of both sexes, aged 45 to 85 with implanted endoprosthesis based on primary osteoarthritis. They were divided into two groups, experimental, which after early rehabilitation continued ongoing rehabilitation for a period of three weeks, while the control group after completion of early rehabilitation began rehabilitation two months from the surgery for a period of three weeks. The range of motion in the knee joint and the extent of the knee joint in the medium of patella were measured in both groups during the admission and discharge from rehabilitation. In the experimental group, control measurements were carried out three months after surgery. Results: In both groups, there was a significant reduction of the swelling at the discharge in relation to the admission while in the experimental group there was no change on the control of the joint swelling after three months in relation to the release from rehabilitation. In the experimental group, the range of motion of flexion and extension was improved at the discharge in relation to the admission as well as the flexion during the control while the range of motion of extension wasn’t significantly changing during the control examination. In the control group, the extension and flexion were significantly improved at the discharge compared to the admission. Comparing both groups, the results showed that there was a significant improvement in flexion movements in the experimental group during rehabilitation in comparison to the control group, while the range of

  14. Design of a continuous passive and active motion device for hand rehabilitation.

    Birch, B; Haslam, E; Heerah, I; Dechev, N; Park, E J

    2008-01-01

    This paper presents the design of a novel, portable device for hand rehabilitation. The device provides for CPM (continuous passive motion) and CAM (continuous active motion) hand rehabilitation for patients recovering from damage such as flexor tendon repair and strokes. The device is capable of flexing/extending the MCP (metacarpophalangeal) and PIP (proximal interphalangeal) joints through a range of motion of 0 degrees to 90 degrees for both the joints independently. In this way, typical hand rehabilitation motions such as intrinsic plus, intrinsic minus, and a fist can be achieved without the need of any splints or attachments. The CPM mode is broken into two subgroups. The first mode is the use of preset waypoints for the device to cycle through. The second mode involves motion from a starting position to a final position, but senses the torque from the user during the cycle. Therefore the user can control the ROM by resisting when they are at the end of the desired motion. During the CPM modes the device utilizes a minimum jerk trajectory model under PD control, moving smoothly and accurately between preselected positions. CAM is the final mode where the device will actively resist the movement of the user. The user moves from a start to end position while the device produces a torque to resist the motion. This active resistance motion is a unique ability designed to mimic the benefits of a human therapist. Another unique feature of the device is its ability to independently act on both the MCP and PIP joints. The feedback sensing built into the device makes it capable of offering a wide and flexible range of rehabilitation programs for the hand.

  15. Complex Human Activity Recognition Using Smartphone and Wrist-Worn Motion Sensors

    Shoaib, Muhammad; Bosch, Stephan; Durmaz Incel, Ozlem; Scholten, Hans; Havinga, Paul J.M.

    2016-01-01

    The position of on-body motion sensors plays an important role in human activity recognition. Most often, mobile phone sensors at the trouser pocket or an equivalent position are used for this purpose. However, this position is not suitable for recognizing activities that involve hand gestures, such

  16. Embodied Semiotic Activities and Their Role in the Construction of Mathematical Meaning of Motion Graphs

    Botzer, Galit; Yerushalmy, Michal

    2008-01-01

    This paper examines the relation between bodily actions, artifact-mediated activities, and semiotic processes that students experience while producing and interpreting graphs of two-dimensional motion in the plane. We designed a technology-based setting that enabled students to engage in embodied semiotic activities and experience two modes of…

  17. Design of a Knee Exoskeleton Using Foot Pressure and Knee Torque Sensors

    Jung-Hoon Kim

    2015-08-01

    Full Text Available This study presents the development of a modular knee exoskeleton system that supports the knee joints of hemiplegic patients. The device is designed to realize the polycentric motion of real human knees using a fourbar linkage and to minimize its total weight. In order to determine the user’s intention, force-sensitive resistors (FSRs in the user’s insole, a torque sensor on the robot knee joint, and an encoder in the motor are used. The control algorithm is based on a finite state machine (FSM, where the force control, position control and virtual damping control are applied in each state. The proposed hardware design and algorithm are verified by performing experiments on the standing, walking and sitting motion controls while wearing the knee exoskeleton.

  18. Spontaneous Motion in Hierarchically Assembled Active Cellular Materials

    Chen, Daniel

    2013-03-01

    With exquisite precision and reproducibility, cells orchestrate the cooperative action of thousands of nanometer-sized molecular motors to carry out mechanical tasks at much larger length scales, such as cell motility, division and replication. Besides their biological importance, such inherently far-from-equilibrium processes are an inspiration for the development of soft materials with highly sought after biomimetic properties such as autonomous motility and self-healing. I will describe our exploration of such a class of biologically inspired soft active materials. Starting from extensile bundles comprised of microtubules and kinesin, we hierarchically assemble active analogs of polymeric gels, liquid crystals and emulsions. At high enough concentration, microtubule bundles form an active gel network capable of generating internally driven chaotic flows that enhance transport and fluid mixing. When confined to emulsion droplets, these 3D networks buckle onto the water-oil interface forming a dense thin film of bundles exhibiting cascades of collective buckling, fracture, and self-healing driven by internally generated stresses from the kinesin clusters. When compressed against surfaces, this active nematic cortex exerts traction stresses that propel the locomotion of the droplet. Taken together, these observations exemplify how assemblies of animate microscopic objects exhibit collective biomimetic properties that are fundamentally distinct from those found in materials assembled from inanimate building blocks. These assemblies, in turn, enable the generation of a new class of materials that exhibit macroscale flow phenomena emerging from nanoscale components.

  19. Fusion of Smartphone Motion Sensors for Physical Activity Recognition

    Shoaib, Muhammad; Bosch, Stephan; Durmaz Incel, Ozlem; Scholten, Hans; Havinga, Paul J.M.

    2014-01-01

    For physical activity recognition, smartphone sensors, such as an accelerometer and a gyroscope, are being utilized in many research studies. So far, particularly, the accelerometer has been extensively studied. In a few recent studies, a combination of a gyroscope, a magnetometer (in a supporting r

  20. The Evaluation of Protein C Activity and Some Inflammatory Markers in Synovia of Patients Undergoing Total Knee Arthroplasty

    Ahmet Ata Alturfan

    2011-06-01

    Full Text Available Objective: Total knee arthroplasty (TKA is a major risk factor for thrombosis in patients over 40 years of age and this risk persists for several weeks after the surgery. Since inflammatory mechanisms affect coagulation and the natural anticoagulant system, we aimed to investigate protein C activities and inflammatory markers in patients undergoing TKA surgery.Material and Methods: We included 20 osteoarthritis patients and 20 healthy controls. Protein C activity and tumor necrosis factor-α (TNF-α levels in plasma and synovia were evaluated by ELISA technique. Results: In the patient group, protein C activities decreased and TNF-α levels increased significantly both in synovia and plasma when compared with the controls. Erythrocyte sedimentation rate of the patient group was found to be significantly elevated in comparison to the controls. On the other hand, serum C reactive protein values increased insignificantly when compared to controls.Conclusion: The decreased activity of protein C and increased levels of inflammatory markers in preoperative plasma and synovia of the patient group may enhance the risk for developing thrombosis.

  1. Total knee arthroplasty for severe valgus knee deformity

    Zhou Xinhua; Wang Min; Liu Chao; Zhang Liang; Zhou Yixin

    2014-01-01

    Background Primary total knee arthroplasty (TKA) in severe valgus knees may prove challenging,and choice of implant depends on the severity of the valgus deformity and the extent of soft-tissue release.The purpose of this study was to review 8 to 11 years (mean,10 years) follow-up results of primary TKA for varient-Ⅲ valgus knee deformity with use of different type implants.Methods Between January 2002 and January 2005,20 women and 12 men,aged 47 to 63 (mean,57.19±6.08) years old,with varient-Ⅲ valgus knees underwent primary TKA.Of the 32 patients,37 knees had varient-Ⅲ deformities.Pie crusting was carefully performed with small,multiple inside-out incisions,bone resection balanced the knee in lieu of soft tissue releases that were not used in the series.Cruciate-retaining knees (Gemini MKⅡ,Link Company,Germany) were used in 13 knees,Genesis Ⅱ (Simth & Nephew Company,USA) in 14 knees,and hinged knee (Endo-Model Company,Germany) in 10 knees.In five patients with bilateral variant-Ⅲll TKAs,three patients underwent 1-stage bilateral procedures,and two underwent 2-stage procedures.All implants were cemented and the patella was not resurfaced.The Hospital for Special Surgery (HSS) knee score was assessed.Patients were followed up from 8 to 11 years.Results The mean HSS knee score were improved from 50.33±11.60 to 90.06±3.07 (P <0.001).The mean tibiofemoral alignment were improved from valgus 32.72°±9.68° pre-operation to 4.89°±0.90° post-operation (P <0.001).The mean range of motion were improved from 93.72°±23.69° pre-operation to 116.61±16.29° post-operation (P <0.001).No patients underwent revision.One patient underwent open reduction and internal fixation using femoral condylar plates for supracondylar femoral fractures secondary to a fall at three years.Three patients developed transient peroneal nerve palsies,which resolved within nine months.Two patients developed symptomatic deep vein thrombosis that was managed with rivaroxaban

  2. What Are the Prognostic Factors for Radiographic Progression of Knee Osteoarthritis? A Meta-analysis

    A.N. Bastick (Alex); J.N. Belo (Janneke); J. Runhaar (Jos); S.M. Bierma-Zeinstra (Sita)

    2015-01-01

    textabstractBackground: A previous systematic review on prognostic factors for knee osteoarthritis (OA) progression showed associations for generalized OA and hyaluronic acid levels. Knee pain, radiographic severity, sex, quadriceps strength, knee injury, and regular sport activities were not associ

  3. The Effect of Continuous Passive Motion after Total Knee Replacement%人工全膝关节置换术后持续被动运动的早期临床效果研究

    范继峰; 张卫国; 李杰; 宫福良

    2011-01-01

    探讨持续被动运动用于人工全膝关节置换术后的早期疗效.自2008年至2010年我科共完成人工全膝关节置换术36例(43膝),将全部病例随机分为2组,A组术后单纯应用物理治疗及自身锻炼,B组采用持续被动锻炼加主动锻炼.观察术后12小时、24小时引流量,术后1周、2周膝关节主动活动范围,切口拆线时间,患者平均住院时间.术后2周彩超检查下肢深静脉血栓的发生情况.2组间在术后12小时、24小时引流量,切口拆线时间,患者平均住院时间及术后2周下肢深静脉血栓的发生率方面均无显著差异(P>0.05).术后第1周及第2周关节主动活动范围方面B组明显优于A组(P<0.05).使用持续被动运动可明显增加人工全膝关节置换术后早期膝关节主动运动范围,并不增加切口并发症的发生率.%To evaluate the early clinical effects of continuous passive motion (CPM ) after total knee replacement (TKR). From 2008 to 2010,36 patients (43 knees) who underwent TKR were divided into 2 groups. Group B were treated with CPM after operation,compared to group A with single physiotherapy and initiative exercise. There was statistically significant difference between the two groups in range of motion (ROM ) in 1 and 2 week after operation. CPM is benefit to the ROM of the joint in early stage post operation.

  4. DEFINITION AND ANALYSIS OF MOTION ACTIVITY AFTER-STROKE PATIENT FROM THE VIDEO STREAM

    M. Yu. Katayev

    2014-01-01

    Full Text Available This article describes an approach to the assessment of motion activity of man in after-stroke period, allowing the doctor to get new information to give a more informed recommendations on rehabilitation treatment than in traditional approaches. Consider description of the hardware-software complex for determination and analysis of motion activity after-stroke patient for the video stream. The article provides a description of the complex, its algorithmic filling and the results of the work on the example of processing of the actual data. The algorithms and technology to significantly accelerate the gait analysis and improve the quality of diagnostics post-stroke patients.

  5. Effect of two different kinesio taping techniques on knee kinematics and kinetics in young females

    Guner, Senem; Alsancak, Serap; KOZ, Mitat

    2015-01-01

    [Purpose] The application of kinesio taping may improve strength and performance, inhibit and facilitate motor activity, and increase range of motion. The aim of this study was to compare the effects of kinesio taping facilitation and inhibition applications on spatiotemporal knee kinematics and kinetics during walking activity in healthy subjects. [Subjects and Methods] A three-dimensional quantitative gait evaluation was performed without tape and with, facilitation and inhibition kinesio t...

  6. Comparison of the Danish Physical Activity Questionnaire with a validated position and motion instrument

    Matthiessen, Jeppe; Biltoft-Jensen, Anja Pia; Rasmussen, Lone Banke;

    2008-01-01

    Objective To compare the Danish Physical Activity Questionnaire (DPAQ) estimating physical activity energy expenditure (PAEE) and physical activity level (PAL) and the pattern of physical activity (including health-related physical activity) with measurements from a validated position and motion...... measured by the ActiReg((R)) (rho = 0.53, P physical activity (MVPA) in healthy adults at group level......), but not for men. The correlation between methods was good for PAEE (r = 0.71, P physical activity (MVPA) (P = 0.40). Time reported in MVPA with the DPAQ was positively correlated with time spent in MVPA...

  7. Arthroscopic knee debridement can delay total knee replacement in painful moderate haemophilic arthropathy of the knee in adult patients.

    Rodriguez-Merchan, E Carlos; Gomez-Cardero, Primitivo

    2016-09-01

    The role of arthroscopic debridement of the knee in haemophilia is controversial in the literature. The purpose of this study is to describe the results of arthroscopic knee debridement (AKD), with the aim of determining whether it is possible to delay total knee replacement (TKR) for painful moderate haemophilic arthropathy of the knee in adult patients. In a 14-year period (1998-2011), AKD was performed for moderate haemophilic arthropathy of the knee in 27 patients with haemophilia A. Their average age at operation was 28.6 years (range 26-39 years). Indications for surgery were as follows: more than 90° of knee flexion, flexion deformity less than 30°, good axial alignment of the knee, good patellar alignment, and pain above >60 points in a visual analogue scale [0 (no pain) to 100 points]. Secondary haematological prophylaxis and rehabilitation (physiotherapy) was given for at least 3 months after surgery. Follow-up was for an average of 7.5 years (range 2-14 years). We assessed the clinical outcome before surgery and at the time of latest follow-up using the Knee Society pain and function scores, the range of motion, and the radiological score of the World Federation of Haemophilia. Knee Society pain scores improved from 39 preoperatively to 66 postoperatively, and function scores improved from 36 to 52. Range of motion improved on an average from -15° of extension and 90° of flexion before surgery, to -5° of extension and 110° of flexion at the last follow-up. A radiological deterioration of 2.8 points on average was found. There were two (7.4%) postoperative complications (haemarthroses resolved by joint aspiration). One patient (3.7%) required a TKR 12.5 years later. AKD should be considered in painful moderate haemophilic arthropathy of the knee in adult patients to delay TKR.

  8. Evaluation of predicted knee-joint muscle forces during gait using an instrumented knee implant.

    Kim, Hyung J; Fernandez, Justin W; Akbarshahi, Massoud; Walter, Jonathan P; Fregly, Benjamin J; Pandy, Marcus G

    2009-10-01

    Musculoskeletal modeling and optimization theory are often used to determine muscle forces in vivo. However, convincing quantitative evaluation of these predictions has been limited to date. The present study evaluated model predictions of knee muscle forces during walking using in vivo measurements of joint contact loading acquired from an instrumented implant. Joint motion, ground reaction force, and tibial contact force data were recorded simultaneously from a single subject walking at slow, normal, and fast speeds. The body was modeled as an 8-segment, 21-degree-of-freedom articulated linkage, actuated by 58 muscles. Joint moments obtained from inverse dynamics were decomposed into leg-muscle forces by solving an optimization problem that minimized the sum of the squares of the muscle activations. The predicted knee muscle forces were input into a 3D knee implant contact model to calculate tibial contact forces. Calculated and measured tibial contact forces were in good agreement for all three walking speeds. The average RMS errors for the medial, lateral, and total contact forces over the entire gait cycle and across all trials were 140 +/- 40 N, 115 +/- 32 N, and 183 +/- 45 N, respectively. Muscle coordination predicted by the model was also consistent with EMG measurements reported for normal walking. The combined experimental and modeling approach used in this study provides a quantitative framework for evaluating model predictions of muscle forces in human movement.

  9. Analysing the Hydraulic Actuator-based Knee Unit Kinematics and Correlating the Numerical Results and Walking Human Knee Joint Behavior

    K. A. Trukhanov

    2014-01-01

    the mechanical device kinematics to replace an amputee’s knee joint.3. An analytical dependence is found for the reduced load on the actuator, which is part of the knee unit, on the time in the bending knee when walking.4. A value of required capacity and a type of analytical dependence in the case of active knee unit is determined.The analysis allows us to conclude the following:1. It is found from the obtained results that the motion and human walk parameters can be described by functional dependencies.2. Calculation has shown that the obtained relationships defining knee joint kinematics can be used to describe a walk of the amputee with artificial limb on the flat surface with accuracy of up to 6 %.3. Established relationships may be useful in other fields of engineering to assess the kinematics of mechanisms with similar structure, such as excavation equipment and robotic systems. 4. The resulting dependence for the reduced load on the stock of A is necessary to perform a shock absorber synthesis.

  10. MAGNETIC HELICITY TRANSPORTED BY FLUX EMERGENCE AND SHUFFLING MOTIONS IN SOLAR ACTIVE REGION NOAA 10930

    Zhang, Y. [Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Sciences, Chaoyang District, Beijing 100012 (China); Kitai, R.; Takizawa, K., E-mail: zhangyin@kwasan.kyoto-u.ac.jp, E-mail: zhangyin@bao.ac.cn [Kwasan and Hida Observatories, Kyoto University, Yamashina-ku, Kyoto 607-8471 (Japan)

    2012-06-01

    We present a new methodology which can determine magnetic helicity transport by the passage of helical magnetic field lines from the sub-photosphere and the shuffling motions of footpoints of preexisting coronal field lines separately. It is well known that only the velocity component, which is perpendicular to the magnetic field ({upsilon}{sub B}), has contributed to the helicity accumulation. Here, we demonstrate that {upsilon}{sub B} can be deduced from a horizontal motion and vector magnetograms under a simple relation of {upsilon}{sub t} = {mu}{sub t} + ({upsilon}{sub n}/B{sub n} ) B{sub t}, as suggested by Demoulin and Berger. Then after dividing {upsilon}{sub B} into two components, as one is tangential and the other is normal to the solar surface, we can determine both terms of helicity transport. Active region (AR) NOAA 10930 is analyzed as an example during its solar disk center passage by using data obtained by the Spectropolarimeter and the Narrowband Filter Imager of Solar Optical Telescope on board Hinode. We find that in our calculation the helicity injection by flux emergence and shuffling motions have the same sign. During the period we studied, the main contribution of helicity accumulation comes from the flux emergence effect, while the dynamic transient evolution comes from the shuffling motions effect. Our observational results further indicate that for this AR the apparent rotational motion in the following sunspot is the real shuffling motions on the solar surface.

  11. Addition of telephone coaching to a physiotherapist-delivered physical activity program in people with knee osteoarthritis: A randomised controlled trial protocol

    Bennell Kim L

    2012-12-01

    Full Text Available Abstract Background Knee osteoarthritis (OA is one of the most common and costly chronic musculoskeletal conditions world-wide and is associated with substantial pain and disability. Many people with knee OA also experience co-morbidities that further add to the OA burden. Uptake of and adherence to physical activity recommendations is suboptimal in this patient population, leading to poorer OA outcomes and greater impact of associated co-morbidities. This pragmatic randomised controlled trial will investigate the clinical- and cost-effectiveness of adding telephone coaching to a physiotherapist-delivered physical activity intervention for people with knee OA. Methods/Design 168 people with clinically diagnosed knee OA will be recruited from the community in metropolitan and regional areas and randomly allocated to physiotherapy only, or physiotherapy plus nurse-delivered telephone coaching. Physiotherapy involves five treatment sessions over 6 months, incorporating a home exercise program of 4–6 exercises (targeting knee extensor and hip abductor strength and advice to increase daily physical activity. Telephone coaching comprises 6–12 telephone calls over 6 months by health practitioners trained in applying the Health Change Australia (HCA Model of Health Change to provide behaviour change support. The telephone coaching intervention aims to maximise adherence to the physiotherapy program, as well as facilitate increased levels of participation in general physical activity. The primary outcomes are pain measured by an 11-point numeric rating scale and self-reported physical function measured by the Western Ontario and McMaster Universities Osteoarthritis Index subscale after 6 months. Secondary outcomes include physical activity levels, quality-of-life, and potential moderators and mediators of outcomes including self-efficacy, pain coping and depression. Relative cost-effectiveness will be determined from health service usage and outcome

  12. Treatment of knee flexion contracture in patients with chronic juvenile arthritis: A case report

    Matijević Radmila

    2006-01-01

    Full Text Available Introduction. Knee flexion contractures are common after-effects of juvenile arthritis. Treatment is usually conservative and may include physical therapy and kinesitherapy. Surgical treatment, particularly of the soft parts, indicated for contractures resistant to conservative treatment, helps to correct the deformity, maintain movements, and relieves pain. Intensive postoperative physiotherapy is of special importance. Case report. A 23-year-old female patient with chronic juvenile arthritis since the age of one was admitted for treatment of flexion con­tractures in both knees, muscle hypotrophy, loss of strength and gait disability. The patient underwent arthroscopic synovectomy. The operation was first performed on the right and after 3 mouths on the left knee. The pre operative range of motion in the rigth knee was 30°-70° and in the left 40°-80°. The patient underwent intensive physical therapy to reduce postoperative swelling of knees and firstly passive and then active kinesitherapy. Nine months after the first surgery and six months after the second, the range of motion in the right knee was 0°-100° and in the left 0°-105°. The strength of tested muscles was increased and gait was improved. Conclusion. Management and rehabilitation of patients with chronic juvenile arthritis include maintenance or improvement in position and function of joints that is achieved with synovectomy. The results depend on combined interdisciplinary rehabilitation, well-experienced staff, and pre- and post-operative physiotherapy as well as kinesitherapy. Arthroscopic synovectomy has many advantages and we believe that it was a better solution than open capsulosynovectomy in this patient with chronic juvenile arthritis of the knee. .

  13. Treatment of knee arthrofibrosis and quadriceps insufficiency after patellar tendon repair: a case report including use of the graston technique.

    Black, Douglass W

    2010-06-23

    Arthrofibrosis of the knee is a surgical complication that can limit range of motion, inhibit muscle activity, and decrease patient function. Optimal conservative treatment has not been well established in the literature, leaving a clinician with limited evidence for treatment planning. Described here is part of the rehabilitative course of care for a patient with arthrofibrotic limitations after a mid-substance patellar tendon repair with augmentation. Marked limitations in knee flexion range of motion and quadriceps activity were addressed using the Graston Technique to deal with soft-tissue adhesions; traditional physical therapy care was also provided. Clear improvement in range of motion and quadriceps activity and function was noted over the course of 5 treatments during 1 month. Treatment process and clinical reasoning are offered to promote understanding and to facilitate future inquiry.

  14. Active experiments and single ion motion in the magnetotail

    Rothwell, P. L.; Yates, G. K.

    1983-07-01

    Analytic solutions to the Lorentz equation which indicate that the magnetic field in the plasma sheet focuses selected ions from the plasma sheet boundaries on the neutral sheet are obtained. The kinetic energy of these ions usually exceeds the threshold energy required for the ion tearing mode instability. Two active experiments based on this effect are proposed. Heavy ions injected towards dusk on the plasma sheet boundary would become focused on the neutral sheet and perhaps trigger the ion tearing mode. A boundary perturbation, such as a thermal chemical release, that locally enhances the boundary turbulence level could be introduced, causing sufficient ksq = 1 ions to be focused on the neutral sheet to trigger the ion tearing mode.

  15. Can origin of the 2400-year cycle of solar activity be caused by solar inertial motion?

    I. Charvátová

    Full Text Available A solar activity cycle of about 2400 years has until now been of uncertain origin. Recent results indicate it is caused by solar inertial motion. First we describe the 178.7-year basic cycle of solar motion. The longer cycle, over an 8000 year interval, is found to average 2402.2 years. This corresponds to the Jupiter/Heliocentre/Barycentre alignments (9.8855 × 243. Within each cycle an exceptional segment of 370 years has been found characterized by a looping pattern by a trefoil or quasitrefoil geometry. Solar activity, evidenced by 14C tree-ring proxies, shows the same pattern. Solar motion is computable in advance, so this provides a basis for future predictive assessments. The next 370-year segment will occur between AD 2240 and 2610.

    Key words: Solar physics (celestial mechanics

  16. POST TRAUMATIC KNEE FRACTURE ( X-RAY

    Dr. Jalaja Prakash.

    2013-06-01

    Full Text Available A 51 year old male patient met with a road traffic accident on August 2010. On examination thepatient was unable to stand and walk. His right knee was swollen and complained of pain withinstability. The X-Ray of patient showed transverse fracture of patella along with comminutedfracture of lower end of femur. He was treated with “K” wire and internal fixation. The patient wasadvised early physiotherapy which include range of motion exercises, knee strengthening and gaittraining.

  17. Electroencephalogram evidence for mirror neuron activity during the observation of drawn hand motion

    Huaping Zhu; Yaoru Sun; Wenya Duan

    2011-01-01

    The present study used electroencephalography to examine mu rhythm suppression (a putative index of human mirror neuron system activation) at frontal sites (F3, Fz and F4), central sites (C3, Cz and C4), parietal sites (P3, Pz and P4) and occipital sites (O1 and O2), while subjects observed real hand motion (real hand motion condition) and illustrative depictions of hand motion (drawn hand motion condition). Experimental data revealed that mu rhythm suppression was exhibited in the mirror neuron system when subjects observed both real and drawn hand motion. Moreover, the mu rhythm recorded at the F3, Fz, F4, and Pz poles was significantly suppressed while observing both stimulus types, but no obvious mu suppression occurred at the O1, O2 and O3 poles. These results suggest that the observation of drawings of human hand actions can activate the human mirror neuron system. This evidence supports the hypothesis that the mirror neuron system may be involved in intransitively abstract action understanding.

  18. Knee microfracture surgery

    Cartilage regeneration - knee ... Three types of anesthesia may be used for knee arthroscopy surgery: Medicine to relax you, and shots of painkillers to numb the knee Spinal (regional) anesthesia General anesthesia (you will be ...

  19. Preventing Knee Injuries

    ... Our Newsletter Donate Blog Skip breadcrumb navigation Preventing Knee Injuries Knee injuries in children and adolescent athletes ... this PDF Share this page: WHAT ARE COMMON KNEE INJURIES? Pain Syndromes One of the most common ...

  20. Complex Human Activity Recognition Using Smartphone and Wrist-Worn Motion Sensors.

    Shoaib, Muhammad; Bosch, Stephan; Incel, Ozlem Durmaz; Scholten, Hans; Havinga, Paul J M

    2016-03-24

    The position of on-body motion sensors plays an important role in human activity recognition. Most often, mobile phone sensors at the trouser pocket or an equivalent position are used for this purpose. However, this position is not suitable for recognizing activities that involve hand gestures, such as smoking, eating, drinking coffee and giving a talk. To recognize such activities, wrist-worn motion sensors are used. However, these two positions are mainly used in isolation. To use richer context information, we evaluate three motion sensors (accelerometer, gyroscope and linear acceleration sensor) at both wrist and pocket positions. Using three classifiers, we show that the combination of these two positions outperforms the wrist position alone, mainly at smaller segmentation windows. Another problem is that less-repetitive activities, such as smoking, eating, giving a talk and drinking coffee, cannot be recognized easily at smaller segmentation windows unlike repetitive activities, like walking, jogging and biking. For this purpose, we evaluate the effect of seven window sizes (2-30 s) on thirteen activities and show how increasing window size affects these various activities in different ways. We also propose various optimizations to further improve the recognition of these activities. For reproducibility, we make our dataset publicly available.

  1. sEMG during Whole-Body Vibration Contains Motion Artifacts and Reflex Activity

    Karin Lienhard

    2015-01-01

    Full Text Available The purpose of this study was to determine whether the excessive spikes observed in the surface electromyography (sEMG spectrum recorded during whole-body vibration (WBV exercises contain motion artifacts and/or reflex activity. The occurrence of motion artifacts was tested by electrical recordings of the patella. The involvement of reflex activity was investigated by analyzing the magnitude of the isolated spikes during changes in voluntary background muscle activity. Eighteen physically active volunteers performed static squats while the sEMG was measured of five lower limb muscles during vertical WBV using no load and an additional load of 33 kg. In order to record motion artifacts during WBV, a pair of electrodes was positioned on the patella with several layers of tape between skin and electrodes. Spectral analysis of the patella signal revealed recordings of motion artifacts as high peaks at the vibration frequency (fundamental and marginal peaks at the multiple harmonics were observed. For the sEMG recordings, the root mean square of the spikes increased with increasing additional loads (p < 0.05, and was significantly correlated to the sEMG signal without the spikes of the respective muscle (r range: 0.54 - 0.92, p < 0.05. This finding indicates that reflex activity might be contained in the isolated spikes, as identical behavior has been found for stretch reflex responses evoked during direct vibration. In conclusion, the spikes visible in the sEMG spectrum during WBV exercises contain motion artifacts and possibly reflex activity.

  2. Population activity in the human dorsal pathway predicts the accuracy of visual motion detection

    Donner, T.H.; Siegel, M.; Oostenveld, R.; Fries, P.; Bauer, M.; Engel, A.K.

    2007-01-01

    A person's ability to detect a weak visual target stimulus varies from one viewing to the next. We tested whether the trial-to-trial fluctuations of neural population activity in the human brain are related to the fluctuations of behavioral performance in a "yes-no" visual motion-detection task. We

  3. Experimental muscle pain during a forward lunge--the effects on knee joint dynamics and electromyographic activity

    Henriksen, Marius; Alkjaer, T; Simonsen, Erik Bruun

    2009-01-01

    . Isotonic saline (0.9%) was used as control. MAIN OUTCOME MEASUREMENTS: Three-dimensional movement analyses were performed and inverse dynamics were used to calculate joint kinematics and kinetics for ankle, knee and hip joints. Electromyographic (EMG) signals of the hamstrings and quadriceps muscles were...... recorded. RESULTS: During and after pain, significant decreases in knee joint dynamics and EMG recordings were observed. CONCLUSION: The study shows that local pain in the quadriceps is capable of modulating movements with high knee joint dynamics. The results may have implications in the management......OBJECTIVE: The purpose of this study was to investigate whether the knee joint dynamics during a forward lunge could be modulated by experimentally induced vastus medialis pain in healthy subjects. DESIGN: Randomised cross-over study. SETTING: Biomechanical movement laboratory. PARTICIPANTS: 20...

  4. Clinical Evaluation of a Mobile Sensor-Based Gait Analysis Method for Outcome Measurement after Knee Arthroplasty

    Tilman Calliess

    2014-08-01

    Full Text Available Clinical scores and motion-capturing gait analysis are today’s gold standard for outcome measurement after knee arthroplasty, although they are criticized for bias and their ability to reflect patients’ actual quality of life has been questioned. In this context, mobile gait analysis systems have been introduced to overcome some of these limitations. This study used a previously developed mobile gait analysis system comprising three inertial sensor units to evaluate daily activities and sports. The sensors were taped to the lumbosacral junction and the thigh and shank of the affected limb. The annotated raw data was evaluated using our validated proprietary software. Six patients undergoing knee arthroplasty were examined the day before and 12 months after surgery. All patients reported a satisfactory outcome, although four patients still had limitations in their desired activities. In this context, feasible running speed demonstrated a good correlation with reported impairments in sports-related activities. Notably, knee flexion angle while descending stairs and the ability to stop abruptly when running exhibited good correlation with the clinical stability and proprioception of the knee. Moreover, fatigue effects were displayed in some patients. The introduced system appears to be suitable for outcome measurement after knee arthroplasty and has the potential to overcome some of the limitations of stationary gait labs while gathering additional meaningful parameters regarding the force limits of the knee.

  5. Clinical evaluation of a mobile sensor-based gait analysis method for outcome measurement after knee arthroplasty.

    Calliess, Tilman; Bocklage, Raphael; Karkosch, Roman; Marschollek, Michael; Windhagen, Henning; Schulze, Mareike

    2014-08-28

    Clinical scores and motion-capturing gait analysis are today's gold standard for outcome measurement after knee arthroplasty, although they are criticized for bias and their ability to reflect patients' actual quality of life has been questioned. In this context, mobile gait analysis systems have been introduced to overcome some of these limitations. This study used a previously developed mobile gait analysis system comprising three inertial sensor units to evaluate daily activities and sports. The sensors were taped to the lumbosacral junction and the thigh and shank of the affected limb. The annotated raw data was evaluated using our validated proprietary software. Six patients undergoing knee arthroplasty were examined the day before and 12 months after surgery. All patients reported a satisfactory outcome, although four patients still had limitations in their desired activities. In this context, feasible running speed demonstrated a good correlation with reported impairments in sports-related activities. Notably, knee flexion angle while descending stairs and the ability to stop abruptly when running exhibited good correlation with the clinical stability and proprioception of the knee. Moreover, fatigue effects were displayed in some patients. The introduced system appears to be suitable for outcome measurement after knee arthroplasty and has the potential to overcome some of the limitations of stationary gait labs while gathering additional meaningful parameters regarding the force limits of the knee.

  6. Motional Stark Effect and Its Active Cancellation in Diamagnetic Spectrum of Barium

    QUAN Wei; LIU Hong-Ping; SHEN Li; ZHAN Ming-Sheng

    2007-01-01

    With time-of-flight and electric field ionization detection technique, we investigate the motional Stark effect for highly excited Rydberg barium in high magnetic field and its active cancellation experimentally. In the experiment, the atom beam is aligned at a small angle of 15° with respect to the magnetic field. The motional Stark effect cancellation is demonstrated on two sets of circularly polarized spectra in static magnetic field B = 1.00000 Tesla and B = 1.70000 Tesla, respectively, although the effect is very small (~ 3.5 Vcm-1) in our apparatus configuration.

  7. Cross-cultural adaptation and validation of the Portuguese version of the Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS)

    Gonçalves, Rui Soles; Cabri, Jan; Pinheiro, João Páscoa

    2008-01-01

    Abstract The objective of this study was to cross-culturally adapt and validate the Portuguese version of the Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS). This version was obtained with forward/backward translations, consensus panels and pre-testing. The Portuguese KOS-ADLS and Medical Outcomes Study, 36-item Short Form (SF-36) questionnaires, visual analogue scales (VAS) of pain, disability and discomfort, and a form for patient’s characteristics were administered to 168...

  8. Modelling and Analysis on Biomechanical Dynamic Characteristics of Knee Flexion Movement under Squatting

    Jianping Wang

    2014-01-01

    Full Text Available The model of three-dimensional (3D geometric knee was built, which included femoral-tibial, patellofemoral articulations and the bone and soft tissues. Dynamic finite element (FE model of knee was developed to simulate both the kinematics and the internal stresses during knee flexion. The biomechanical experimental system of knee was built to simulate knee squatting using cadaver knees. The flexion motion and dynamic contact characteristics of knee were analyzed, and verified by comparing with the data from in vitro experiment. The results showed that the established dynamic FE models of knee are capable of predicting kinematics and the contact stresses during flexion, and could be an efficient tool for the analysis of total knee replacement (TKR and knee prosthesis design.

  9. Severe Heterotopic Ossification following Total Knee Replacement

    Alexander L. Dodds

    2014-01-01

    Full Text Available Although the incidence of minor heterotopic ossification is probably higher than what is usually expected, severe heterotopic ossification (HO is an extremely rare event following total knee replacement surgery. We present the case of a 66-year-old woman who initially had achieved an excellent range of motion following bilateral uncemented rotating platform total knee replacement, before presenting with pain and loss of range of motion at 2 months after surgery. Severe HO was diagnosed on X-rays. Treatment consisted of nonoperative measures only, including physiotherapy with hydrotherapy and anti-inflammatories. She eventually regained her range of motion when seen at 8 months after operation. This case illustrates that nonoperative treatment without the use of radiotherapy or surgery can be used to safely resolve stiffness caused by HO after total knee replacement.

  10. Preclinical computational models: predictors of tibial insert damage patterns in total knee arthroplasty: AAOS exhibit selection.

    Morra, Edward A; Heim, Christine S; Greenwald, A Seth

    2012-09-19

    Computational models that predict clinical surface damage of the tibial insert during activities of daily living are emerging as powerful tools to assess the safety and efficacy of contemporary total knee arthroplasty designs. These models have the advantage of quickly determining the performance of new designs at low cost, and they allow direct comparison with the performance of classic, clinically successful designs. This study validated finite element and kinematic modeling predictions through comparison with preclinical physical testing results, damage patterns on retrieved tibial inserts, and clinically measured knee motion. There is a mounting body of evidence to support the role of computational modeling as a preclinical tool that enables the optimization of total knee arthroplasty designs and the auditing of component quality control before large-scale manufacturing is undertaken.

  11. Impact of lumbar spine posture on thoracic spine motion and muscle activation patterns.

    Nairn, Brian C; Drake, Janessa D M

    2014-10-01

    Complex motion during standing is typical in daily living and requires movement of both the thoracic and lumbar spine; however, the effects of lumbar spine posture on thoracic spine motion patterns remain unclear. Thirteen males moved to six positions involving different lumbar (neutral and flexed) and thoracic (flexed and twisted) posture combinations. The thoracic spine was partitioned into three segments and the range of motion from each posture was calculated. Electromyographical data were collected from eight muscles bilaterally. Results showed that with a flexed lumbar spine, the lower-thoracic region had 14.83 ° and 15.6 1 ° more flexion than the upper- and mid-thoracic regions, respectively. A flexed lumbar spine significantly reduced the mid-thoracic axial twist angle by 5.21 ° compared to maximum twist in the mid-thoracic region. Functional differences emerged across muscles, as low back musculature was greatest in maintaining flexed lumbar postures, while thoracic erector spinae and abdominals showed bilateral differences with greater activations to the ipsilateral side. Combined postures have been previously identified as potential injury modulators and bilateral muscle patterns can have an effect on loading pathways. Overall, changes in thoracic motion were modified by lumbar spine posture, highlighting the importance of considering a multi-segmented approach when analyzing trunk motion.

  12. Suspected feigned knee extensor weakness: usefulness of 3D gait analysis. Case report.

    Chaler, Joaquim; Müller, Bertram; Maiques, Anna; Pujol, Eduard

    2010-07-01

    The purpose of the present case report is to show the potential for use of 3D gait analysis as an assessment method of feigned muscle weakness. We describe a patient complaining of right leg pain and weakness. Physical examination showed severe quadriceps muscle weakness in a highly abnormal gait pattern context. Conventional diagnostic workup did not show any relevant findings. Three-dimensional (3D) gait analysis was performed with a 3D motion capture system. Joint angles, internal moments and powers were computed from the motion data. Lower leg muscle surface-electromyography was also performed. During the late stance phase, flexor moment and negative power peaks (indicating eccentric knee extensor activity) were generated in the knee, together with relevant Rectus femoris activity. All findings were highly inconsistent with true quadriceps weakness and gave objective ground to suspect insincerity of patient complaints. 3D gait analysis might be a valuable clinical assessment tool in suspected feigned lower limb muscle weakness.

  13. Analysis of in vitro and in vivo function of total knee replacements using dynamic contact models

    Zhao, Dong

    Despite the high incidence of osteoarthritis in human knee joint, its causes remain unknown. Total knee replacement (TKR) has been shown clinically to be effective in restoring the knee function. However, wear of ultra-high molecular weight polyethylene has limited the longevity of TKRs. To address these important issues, it is necessary to investigate the in vitro and in vivo function of total knee replacements using dynamic contact models. A multibody dynamic model of an AMTI knee simulator was developed. Incorporating a wear prediction model into the contact model based on elastic foundation theory enables the contact surface to take into account creep and wear during the dynamic simulation. Comparisons of the predicted damage depth, area, and volume lost with worn retrievals from a physical machine were made to validate the model. In vivo tibial force distributions during dynamic and high flexion activities were investigated using the dynamic contact model. In vivo medial and lateral contact forces experienced by a well-aligned instrumented knee implant, as well as upper and lower bounds on contact pressures for a variety of activities were studied. For all activities, the predicted medial and lateral contact forces were insensitive to the selected material model. For this patient, the load split during the mid-stance phase of gait and during stair is more equal than anticipated. The external knee adduction torque has been proposed as a surrogate measure for medial compartment load during gait. However, a direct link between these two quantities has not been demonstrated using in vivo measurement of medial compartment load. In vivo data collected from a subject with an instrumented knee implant were analyzed to evaluate this link. The subject performed five different overground gait motions (normal, fast, slow, wide, and toe out) while instrumented implant, video motion, and ground reaction data were simultaneously collected. The high correlation coefficient

  14. A bio-inspired test system for bionic above-knee prosthetic knees

    Wang, Dai-Hua; Xu, Lei; Fu, Qiang; Yuan, Gang

    2013-04-01

    Recently, prosthetic knees in the developing stage are usually tested by installing them on amputees' stumps directly or on above-knee prostheses (AKPs) test platforms. Although amputees can fully provide the actual motion state of the thigh, immature prosthetic knees may hurt amputees. For AKPs test platforms, it just can partly simulate the actual motion state of the thigh with limitation of the motion curve of the thigh, the merits or demerits of newly developed bionic above-knee prosthetic knees cannot be accessed thoroughly. Aiming at the defects of two testing methods, this paper presents a bio-inspired AKPs test system for bionic above-knee prosthetic knees. The proposed bio-inspired AKPs test system is composed of a AKPs test platform, a control system, and a bio-inspired system. The AKPs test platform generates the motion of the thigh simulation mechanism (TSM) via two screw pairs with servo motors. The bio-inspired system includes the tester and the bio-inspired sensor wore by the tester. The control system, which is inspired by the bio-inspired system, generates the control command signal to move the TSM of the AKPs test platform. The bio-inspired AKPs test system is developed and experimentally tested with a commercially available prosthetic knee. The research results show that the bio-inspired AKPs test system can not only ensure the safety of the testers, but also track all kinds of the actual motion state of the thigh of the testers in real time.

  15. EFFECTS OF THE GENIUM MICROPROCESSOR KNEE SYSTEM ON KNEE MOMENT SYMMETRY DURING HILL WALKING.

    Highsmith, M Jason; Klenow, Tyler D; Kahle, Jason T; Wernke, Matthew M; Carey, Stephanie L; Miro, Rebecca M; Lura, Derek J

    2016-09-01

    Use of the Genium microprocessor knee (MPK) system reportedly improves knee kinematics during walking and other functional tasks compared to other MPK systems. This improved kinematic pattern was observed when walking on different hill conditions and at different speeds. Given the improved kinematics associated with hill walking while using the Genium, a similar improvement in the symmetry of knee kinetics is also feasible. The purpose of this study was to determine if Genium MPK use would reduce the degree of asymmetry (DoA) of peak stance knee flexion moment compared to the C-Leg MPK in transfemoral amputation (TFA) patients. This study used a randomized experimental crossover of TFA patients using Genium and C-Leg MPKs (n = 20). Biomechanical gait analysis by 3D motion tracking with floor mounted force plates of TFA patients ambulating at different speeds on 5° ramps was completed. Knee moment DoA was significantly different between MPK conditions in the slow and fast uphill as well as the slow and self-selected downhill conditions. In a sample of high-functioning TFA patients, Genium knee system accommodation and use improved knee moment symmetry in slow speed walking up and down a five degree ramp compared with C-Leg. Additionally, the Genium improved knee moment symmetry when walking downhill at comfortable speed. These results likely have application in other patients who could benefit from more consistent knee function, such as older patients and others who have slower walking speeds.

  16. MR-based motion correction for PET imaging using wired active MR microcoils in simultaneous PET-MR: Phantom study

    Huang, Chuan; Brady, Thomas J.; El Fakhri, Georges; Ouyang, Jinsong, E-mail: ouyang.jinsong@mgh.harvard.edu [Center for Advanced Medical Imaging Sciences, Division of Nuclear Medicine and Molecular Imaging, Department of Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114 and Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115 (United States); Ackerman, Jerome L. [Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129 and Department of Radiology, Harvard Medical School, Boston, Massachusetts 02115 (United States); Petibon, Yoann [Center for Advanced Medical Imaging Sciences, Division of Nuclear Medicine and Molecular Imaging, Department of Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States)

    2014-04-15

    Purpose: Artifacts caused by head motion present a major challenge in brain positron emission tomography (PET) imaging. The authors investigated the feasibility of using wired active MR microcoils to track head motion and incorporate the measured rigid motion fields into iterative PET reconstruction. Methods: Several wired active MR microcoils and a dedicated MR coil-tracking sequence were developed. The microcoils were attached to the outer surface of an anthropomorphic{sup 18}F-filled Hoffman phantom to mimic a brain PET scan. Complex rotation/translation motion of the phantom was induced by a balloon, which was connected to a ventilator. PET list-mode and MR tracking data were acquired simultaneously on a PET-MR scanner. The acquired dynamic PET data were reconstructed iteratively with and without motion correction. Additionally, static phantom data were acquired and used as the gold standard. Results: Motion artifacts in PET images were effectively removed by wired active MR microcoil based motion correction. Motion correction yielded an activity concentration bias ranging from −0.6% to 3.4% as compared to a bias ranging from −25.0% to 16.6% if no motion correction was applied. The contrast recovery values were improved by 37%–156% with motion correction as compared to no motion correction. The image correlation (mean ± standard deviation) between the motion corrected (uncorrected) images of 20 independent noise realizations and static reference was R{sup 2} = 0.978 ± 0.007 (0.588 ± 0.010, respectively). Conclusions: Wired active MR microcoil based motion correction significantly improves brain PET quantitative accuracy and image contrast.

  17. A Review of Accelerometry-Based Wearable Motion Detectors for Physical Activity Monitoring

    Che-Chang Yang

    2010-08-01

    Full Text Available Characteristics of physical activity are indicative of one’s mobility level, latent chronic diseases and aging process. Accelerometers have been widely accepted as useful and practical sensors for wearable devices to measure and assess physical activity. This paper reviews the development of wearable accelerometry-based motion detectors. The principle of accelerometry measurement, sensor properties and sensor placements are first introduced. Various research using accelerometry-based wearable motion detectors for physical activity monitoring and assessment, including posture and movement classification, estimation of energy expenditure, fall detection and balance control evaluation, are also reviewed. Finally this paper reviews and compares existing commercial products to provide a comprehensive outlook of current development status and possible emerging technologies.

  18. Retrospective comparison of functional and radiological outcome, between two contemporary high flexion knee designs

    Kapoor Vikash

    2016-01-01

    Full Text Available Introduction: Patient satisfaction after total knee replacement (TKR depends on the amount of pain relief and the functional activities achieved. An important criterion of good functional outcome is the amount of flexion achieved and whether the patient can manage high flexion activities. In order to increase the amount of safe flexion, various implant designs have been developed. This study aims to compare the outcome after TKR using two contemporary high flexion knee designs: Sigma CR150 High Flex Knee prosthesis (Depuy, Warsaw, Indiana and NexGen High Flex Knee prosthesis (Zimmer, Warsaw, Indiana. Material: A retrospective study was conducted with 100 cases of each design and their functional and radiological outcome was assessed after two years of follow-up. Results: The two groups had comparable results in terms of subjective satisfaction, range of motion achieved and radiological outcome. Depuy group fared better than Zimmer in terms of functional outcome (modified Oxford knee score. Conclusion: Depuy group was found to have fared better than Zimmer in terms of functional outcome. However, it is very difficult to rate one design above the other based on our small sample size and short duration of follow-up.

  19. Retrospective comparison of functional and radiological outcome, between two contemporary high flexion knee designs

    Kapoor, Vikash; Chatterjee, Daipayan; Hazra, Sutanu; Chatterjee, Anirban; Garg, Parag; Debnath, Kaustav; Mandal, Soham; Sarkar, Sudipto

    2016-01-01

    Introduction: Patient satisfaction after total knee replacement (TKR) depends on the amount of pain relief and the functional activities achieved. An important criterion of good functional outcome is the amount of flexion achieved and whether the patient can manage high flexion activities. In order to increase the amount of safe flexion, various implant designs have been developed. This study aims to compare the outcome after TKR using two contemporary high flexion knee designs: Sigma CR150 High Flex Knee prosthesis (Depuy, Warsaw, Indiana) and NexGen High Flex Knee prosthesis (Zimmer, Warsaw, Indiana). Material: A retrospective study was conducted with 100 cases of each design and their functional and radiological outcome was assessed after two years of follow-up. Results: The two groups had comparable results in terms of subjective satisfaction, range of motion achieved and radiological outcome. Depuy group fared better than Zimmer in terms of functional outcome (modified Oxford knee score). Conclusion: Depuy group was found to have fared better than Zimmer in terms of functional outcome. However, it is very difficult to rate one design above the other based on our small sample size and short duration of follow-up. PMID:27748254

  20. Design, fabrication, and preliminary results of a novel below knee prosthesis for snowboarding: A case report

    Minnoye, A.L.M.; Plettenburg, D.H.

    2010-01-01

    Snowboarding with a below-knee prosthesis is compromised by the limited rotation capabilities of the existing below-knee prostheses, which are designed for use in normal walking. Based on snowboarding range of motion analyses, a novel below-knee prosthesis was designed with the aim to achieve simila

  1. Prospective Study of the Relation between Landing Biomechanics and Jumper's Knee

    van der Worp, H.; van der Does, H. T. D.; Brink, M. S.; Zwerver, J.; Hijmans, J. M.

    2016-01-01

    The literature on the relation between jump biomechanics and jumper's knee indicates that a jump with horizontal displacement poses a threat for developing jumper's knee. Subjects with jumper's knee have been shown to display a stiff landing pattern characterized by a small range of motion. However,

  2. Biomechanical Analysis of the Effects of Bilateral Hinged Knee Bracing

    Lee, Hangil; Ha, Dokyeong; Kang, Yeoun-Seung; Park, Hyung-Soon

    2016-01-01

    This research analyzed the effect of bilateral hinged knee braces on a healthy knee from a biomechanical frame in vivo. This was accomplished by fitting a knee brace with two customized wireless force/torque (F/T) sensors that could readily record force and torque during live motion, while the kinetics at the knee were computed using the inverse dynamics of the motion capture and force plate data. Four tasks to test the brace’s effects were drop vertical jumping, pivoting, stop vertical jumping, and cutting. The results showed that the hinges in the knee brace can absorb up to 18% of the force and 2.7% of the torque at the knee during various athletic motions. Thus, the hinges demonstrated minimal effect in reducing the mechanical load on the knee. There were limitations concerning the consistency of the motions performed by the subjects during the trials and the influence of the other portions of the brace to evaluate the overall effectiveness of the brace as a whole. Future works may incorporate a fatigue protocol and injured subjects to better determine the effects of the brace. There is still a need for more research on the biomechanical influence of knee braces to develop safer and more effective products. PMID:27379233

  3. Biomechanical Analysis of the Effects of Bilateral Hinged Knee Bracing.

    Lee, Hangil; Ha, Dokyeong; Kang, Yeoun-Seung; Park, Hyung-Soon

    2016-01-01

    This research analyzed the effect of bilateral hinged knee braces on a healthy knee from a biomechanical frame in vivo. This was accomplished by fitting a knee brace with two customized wireless force/torque (F/T) sensors that could readily record force and torque during live motion, while the kinetics at the knee were computed using the inverse dynamics of the motion capture and force plate data. Four tasks to test the brace's effects were drop vertical jumping, pivoting, stop vertical jumping, and cutting. The results showed that the hinges in the knee brace can absorb up to 18% of the force and 2.7% of the torque at the knee during various athletic motions. Thus, the hinges demonstrated minimal effect in reducing the mechanical load on the knee. There were limitations concerning the consistency of the motions performed by the subjects during the trials and the influence of the other portions of the brace to evaluate the overall effectiveness of the brace as a whole. Future works may incorporate a fatigue protocol and injured subjects to better determine the effects of the brace. There is still a need for more research on the biomechanical influence of knee braces to develop safer and more effective products.

  4. Strong Ground Motion Evaluation for an Active Fault System by the Empirical Green Function Method

    Choi, In Kil; Choun, Young Sun [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Shiba, Yoshiaki; Ohtori, Yasuki [Central Research Institute of Electric Power Industry, Chiba (Japan)

    2005-07-01

    In an area with a high seismic activity, a design earthquake ground motion is generally determined empirically by investigating the historical records concerning damaging events. But it is difficult in Korea to obtain such seismic records that reflect the local characteristics because of the low seismic activity. A geological survey on the active faults near the sites of nuclear power plants has been carried out recently, and the segmentation, slip rate and the latest activity of the fault system are partly revealed. It will be significant for the advanced seismic design of nuclear facilities to utilize the information derived from these geological investigations and evaluate the strong ground motions. In this study, the empirical Green's function method (EFGM) was used to simulate strong ground motions from an active fault system in Korea. The source models are assumed by using the information obtained from the geological survey and the trench investigation on the fault system. Finally, the applicability of this approach to Korea was estimated.

  5. Examining the Magnetic Field Strength and the Horizontal and Vertical Motions in an Emerging Active Region

    Lin, Chia-Hsien

    2016-01-01

    Earlier observational studies have used the time evolution of emerging magnetic flux regions at the photosphere to infer their subsurface structures, assuming that the flux structure does not change significantly over the near-surface layer.In this study, we test the validity of this assumption by comparing the horizontal and vertical motions of an emerging active region. The two motions would be correlated if the emerging structure is rigid. The selected active region (AR) NOAA 11645 is not embedded in detectable preexisting magnetic field. The observed horizontal motion is quantified by the separation of the two AR polarities and the extension of the region. The vertical motion is derived from the magnetic buoyancy theory. Our results show that the separation of the polarities is fastest at the beginning with a velocity of $\\approx$~4~Mm hr$^{-1}$ and decreases to $\\le$~1~Mm hr$^{-1}$ after the main growing phase of flux emergence. The derived thick flux-tube buoyant velocity is between 1 and 3~Mm hr$^{-1}$...

  6. How crouch gait can dynamically induce stiff-knee gait.

    van der Krogt, Marjolein M; Bregman, Daan J J; Wisse, Martijn; Doorenbosch, Caroline A M; Harlaar, Jaap; Collins, Steven H

    2010-04-01

    Children with cerebral palsy frequently experience foot dragging and tripping during walking due to a lack of adequate knee flexion in swing (stiff-knee gait). Stiff-knee gait is often accompanied by an overly flexed knee during stance (crouch gait). Studies on stiff-knee gait have mostly focused on excessive knee muscle activity during (pre)swing, but the passive dynamics of the limbs may also have an important effect. To examine the effects of a crouched posture on swing knee flexion, we developed a forward-dynamic model of human walking with a passive swing knee, capable of stable cyclic walking for a range of stance knee crouch angles. As crouch angle during stance was increased, the knee naturally flexed much less during swing, resulting in a 'stiff-knee' gait pattern and reduced foot clearance. Reduced swing knee flexion was primarily due to altered gravitational moments around the joints during initial swing. We also considered the effects of increased push-off strength and swing hip flexion torque, which both increased swing knee flexion, but the effect of crouch angle was dominant. These findings demonstrate that decreased knee flexion during swing can occur purely as the dynamical result of crouch, rather than from altered muscle function or pathoneurological control alone.

  7. Septic arthritis of the knee following anterior cruciate ligament reconstruction

    Matjaz Sajovic

    2009-04-01

    Full Text Available Septic arthritis of the knee is a rare complication after arthroscopic anterior cruciate ligament reconstruction, and the most appropriate treatment is unclear. All case series reported so far have been retrospective, and case numbers of septic arthritis have ranged from 4 to 11. From a consecutive case series of 1,283 patients who underwent arthroscopic anterior cruciate ligament reconstruction between January 1997 and May 2008, we report on 3 patients (0.23% with post-operative septic arthritis. All patients had acute infection (≤ 2 weeks, bacterial cultures showed Staphylococcus species in 2 patients, while the bacterial culture was negative in the third. All of them underwent immediate arthroscopic debridement and lavage with continuous irrigation, as well as antibiotic treatment. The results were evaluated with physical and radiographic examination, functional testing, KT-2000, Lysholm and Tegner scales. The infection was successfully eradicated without further surgical treatment and the ligament graft was retained in all patients. Follow-up, at an average of 33 months, revealed that the patients had full symmetric knee range of motion and no effusion. The average Lysholm score was 91 points. In the patient with a lower subjective score, radiographs demonstrated patellofemoral joint-space narrowing, which is most probably in correlation with his anterior knee pain problems and lower activity level. The 134 N KT-2000 arthrometer side-to-side differences averaged 13 mm. Their performance in the single-legged hop test gave excellent results. The goals of treatment for septic arthritis after anterior cruciate ligament reconstruction are, primarily, to protect the articular cartilage and, secondly, to protect the graft. Through early diagnosis and prompt treatment, the infection can be successfully eradicated, with stability of the knee and full range of motion achieved.

  8. EFFECTIVENESS OF PNF STRETCHING VERSUS STATIC STRETCHING ON PAIN AND HAMSTRING FLEXIBILITY FOLLOWING MOIST HEAT IN INDIVIDUALS WITH KNEE OSTEOARTHRITIS

    Meena .V

    2016-10-01

    Full Text Available Background: Osteoarthritis (OA is a degenerative joint disease and one of the major public health problem that causesfunctional impairment and reduced quality of life. To compare the effectiveness of PNF Hold relax stretching versus Static stretching on pain and flexibility of hamstring following moist heat in individuals with knee osteoarthritis. Hamstring tightness is the major problem in knee osteoarthritis individuals. Therefore the need of study is comparing the effectiveness of PNF Hold relax stretching versus static stretching on pain and flexibility of hamstrings following moist heat in knee osteoarthritis participants. Determining the effects of PNF Hold relax stretching versus Static stretching along with moist heat on pain and hamstring flexibility by VAS and Active knee extension range of motion in knee osteoarthritis individuals. Methods: 30 subjects with symptoms of knee osteoarthritis were randomly distributed into 2 groups 15 in each group. PNF Hold relax stretching along with moist heat is compared to Static stretching along with moist heat. Pain was measured by Visual Analogue Scale (VAS and hamstring flexibility by Active knee Extension Range of Motion (AKEROM by universal goniometer. Measurements are taken pre and post intervention. Results: The results indicated PNF Hold relax stretching along with moist heat showed a statistically significant improvement in pain (p<0.05 and improvement in hamstring flexibility (p<0.05 when compared to Static stretching along with moist heat. Conclusion: Subjects with PNF Hold relax stretching along with moist heat showed significant improvement in pain reduction and improving hamstring flexibility than Static stretching along with moist heat.

  9. Kinematics of hip, knee, ankle of the young and elderly Chinese people during kneeling activity*

    Zhou, Hai; Wang, Dong-Mei; Liu, Tao-ran; Zeng, Xiang-sen; Wang, Cheng-tao

    2012-01-01

    Objective: The purpose of this study was to measure the kinematics of the lower limbs of Chinese people during normal kneeling activity, as such data could be valuable in designing joint prosthesis and arthroplasty that meet the needs of Chinese citizens’ daily activities. Methods: Thirty young and twenty elderly Chinese participants with no personal history of joint diseases were recruited, and matched by age (average age: 23.8 years for the young group, 60.8 years for the elderly group). Ea...

  10. Prediction of in vivo joint mechanics of an artificial knee implant using rigid multi-body dynamics with elastic contacts.

    Chen, Zhenxian; Zhang, Xuan; Ardestani, Marzieh M; Wang, Ling; Liu, Yaxiong; Lian, Qin; He, Jiankang; Li, Dichen; Jin, Zhongmin

    2014-06-01

    Lower extremity musculoskeletal computational models play an important role in predicting joint forces and muscle activation simultaneously and are valuable for investigating functional outcomes of the implants. However, current computational musculoskeletal models of total knee replacement rarely consider the bearing surface geometry of the implant. Therefore, these models lack detailed information about the contact loading and joint motion which are important factors for evaluating clinical performances. This study extended a rigid multi-body dynamics simulation of a lower extremity musculoskeletal model to incorporate an artificial knee joint, based upon a novel force-dependent kinematics method, and to characterize the in vivo joint contact mechanics during gait. The developed musculoskeletal total knee replacement model integrated the rigid skeleton multi-body dynamics and the flexible contact mechanics of the tibiofemoral and patellofemoral joints. The predicted contact forces and muscle activations are compared against those in vivo measurements obtained from a single patient with good agreements for the medial contact force (root-mean-square error = 215 N, ρ = 0.96) and lateral contact force (root-mean-square error = 179 N, ρ = 0.75). Moreover, the developed model also predicted the motion of the tibiofemoral joint in all degrees of freedom. This new model provides an important step toward the development of a realistic dynamic musculoskeletal total knee replacement model to predict in vivo knee joint motion and loading simultaneously. This could offer a better opportunity to establish a robust virtual modeling platform for future pre-clinical assessment of knee prosthesis designs, surgical procedures and post-operation rehabilitation.

  11. Isokinetic and isometric muscle function of the knee extensors and flexors during simulated soccer activity: effect of exercise and dehydration.

    Ali, Ajmol; Williams, Clyde

    2013-01-01

    This study investigated the influence of dehydration during soccer-type intermittent exercise on isokinetic and isometric muscle function. Eight soccer players performed two 90-min high-intensity intermittent shuttle-running trials without (NF) or with (FL) fluid ingestion (5 ml · kg(-1) before and 2 ml · kg(-1) every 15 min). Isokinetic and isometric strength and muscular power of knee flexors and knee extensors were measured pre-exercise, at half-time and post-exercise using isokinetic dynamometry. Sprint performance was monitored throughout the simulated-soccer exercise. Isokinetic knee strength was reduced at faster (3.13 rad · s(-1); P = 0.009) but not slower (1.05 rad · s(-1); P = 0.063) contraction speeds with exercise; however, there was no difference between FL and NF. Peak isometric strength of the knee extensors (P = 0.002) but not the knee flexors (P = 0.065) was significantly reduced with exercise with no difference between FL and NF. Average muscular power was reduced over time at both 1.05 rad · s(-1) (P = 0.01) and 3.14 rad · s(-1) (P = 0.033) but was not different between FL and NF. Mean 15-m sprint time increased with duration of exercise (P = 0.005) but was not different between FL and NF. In summary, fluid ingestion during 90 min of soccer-type exercise was unable to offset the reduction in isokinetic and isometric strength and muscular power of the knee extensors and flexors.

  12. Motion interactive games for children with motor disorders : motivation, physical activity, and motor control

    Sandlund, Marlene

    2011-01-01

    As motion interactive games have become more widespread the interest in using these games in rehabilitation of children with motor disorders has increased among both clinical professionals and the families of these children. The general aim of this thesis was to evaluate the feasibility of using interactive games in rehabilitation of children to promote motivation for practice, physical activity, and motor control. A systematic review of published intervention studies was conducted to obtain ...

  13. Influence of patellofemoral bracing on pain, knee extensor torque, and gait function in females with patellofemoral pain.

    Powers, Christopher M; Doubleday, Kathryn L; Escudero, Carina

    2008-01-01

    Our purpose was to evaluate the effects of a patellofemoral brace on pain response, knee extensor torque production, and gait function in females with patellofemoral pain (PFP). Sixteen females between the ages of 14 and 46 with diagnosis of PFP participated. Knee extensor torque was measured by using a LIDO isokinetic dynamometer. Pain levels were documented by using the Visual Analog Pain Scale. Stride characteristics during the conditions of free walk, fast walk, ascend stairs, descend stairs, ascend ramp, and descend ramp were obtained with a stride analyzer unit. EMG activity of the vasti musculature was recorded by using indwelling, bipolar, wire electrodes. Knee joint motion was assessed by using a VICON motion analysis system. All testing was performed with and without the Bauerfeind Genutrain P3 patellofemoral brace. There were no significant differences in torque production, pain levels, and stride characteristics between braced and non-braced trials. In addition, there were no significant differences in mean vasti EMG between braced and non-braced trials. When averaged across all conditions, a small but statistically significant increase in knee flexion was found during the braced trials. Although the current study did not find significant improvements in the clinical measures evaluated, 8 of the 16 subjects did experience a decrease in knee pain. This finding suggests that certain patients with PFP may respond favorably to bracing, and criteria must be established to determine which patients would best benefit from such an intervention.

  14. Biomechanics of hyperflexion and kneeling before and after total knee arthroplasty.

    Lee, Thay Q

    2014-06-01

    The capacity to perform certain activities is frequently compromised after total knee arthroplasty (TKA) due to a functional decline resulting from decreased range of motion and a diminished ability to kneel. In this manuscript, the current biomechanical understanding of hyperflexion and kneeling before and after TKA will be discussed. Patellofemoral and tibiofemoral joint contact area, contact pressure, and kinematics were evaluated in cadaveric studies using a Tekscan pressure measuring system and Microscribe. Testing was performed on intact knees and following cruciate retaining and posterior stabilized TKA at knee flexion angles of 90°, 105°, 120°, and 135°. Three loading conditions were used to simulate squatting, double stance kneeling, and single stance kneeling. Following TKA with double stance kneeling, patellofemoral contact areas did not increase significantly at high knee flexion angle (135°). Kneeling resulted in tibial posterior translation and external rotation at all flexion angles. Moving from double to single stance kneeling tended to increase pressures in the cruciate retaining group, but decreased pressures in the posterior stabilized group. The cruciate retaining group had significantly larger contact areas than the posterior stabilized group, although no significant differences in pressures were observed comparing the two TKA designs (p < 0.05). If greater than 120° of postoperative knee range of motion can be achieved following TKA, then kneeling may be performed with less risk in the patellofemoral joint than was previously believed to be the case. However, kneeling may increase the likelihood of damage to cartilage and menisci in intact knees and after TKA increases in tibiofemoral contact area and pressures may lead to polyethyelene wear if performed on a chronic, repetitive basis.

  15. 具有双屈伸运动人工半膝关节假体运动参数分析及实验性临床研究%Motion parameters analysis and pilot clinical trials of the dual mobility hemi-knee artificial prosthesis

    革军; 王臻; 刘鹏; 栗向东; 陈国景

    2012-01-01

    目的 针对儿童股骨下段恶性骨肿瘤的诸多治疗方法中存在的问题,本课题组首次提出具有双屈伸运动人工半膝关节(双动半膝关节)的概念,进行其运动轨迹规律及实验性临床研究.方法 以Mimics/Geomagic/Pro-E软件的设计路线为技术路线.基于成人膝关节标本的CT数据,利用数控铣床机加工制作双动半膝关节假体,进行体外实验研究其运动参数特点,最后进行实验性临床研究.结果 离体实验结果:股骨内侧髁屈曲面球心位移在正常膝关节组为(2.59±0.43)mm,双动半膝关节组为(2.22±0.52) mm,全膝关节组为(1.18±0.43) mm;股骨外侧髁屈曲面球心位移在正常膝关节组为(11.95±6.62) mm,双动半膝关节组为(11.25±6.19)mm,全膝关节组为(1.26±0.42) mm;相对胫骨最大旋转角度在正常膝关节组为13.17°±7.58°,双动半膝关节组为11.69°±6.49°,全膝关节组为5.40°±1.29°.完成探索性临床试验,术后患者恢复良好,效果满意.结论 运动参数分析证明双动半膝关节接近正常膝关节运动模式,双动半膝关节为治疗儿童股骨下段恶性肿瘤提供了全新的理念和思路,新型附丽概念和新型韧带附丽装置为膝关节韧带功能重建提出新的解决方案.%Objective Aim at the problems in the treatments of the children malignant bone tumor of distal femur,we put forward the concept of the dual mobility hemi-knee prosthesis and try to perform the motion parameters analysis and the pilot clinical trials.Methods Base on the CT data from samples of knee joint in adult,we adopted the Mimics/Geomagic/Pro-E software and computer numerical control milling machine technology to design and produce the dual mobility hemi-knee artificial prosthesis,and then motion parameters was analyzed in vitro test,and at last pilot clinical trial was performed.Results In vitro experiment showed that the displacement of the internal femoral condyle flexion facet center was (2

  16. Knee osteoarthritis therapy through traditional Chinese herb smoking%中药薰洗治疗膝关节骨性关节炎

    徐振奇; 姜贵云; 刘旭东; 柴叶红; 李青

    2003-01-01

    @@ INTRODUCTION Knee osteoarthritis is a regenerated change of knee hyaline cartilage, complicated with bone hyperplasia,synovitis and articular capsule and muscle changes due to old age and knee joint injury, deformity and diseases etc factors.Osteoarthritis induced many clinical manifestations including knee ache,swelling and limited motion and seriously affected the quality of the patients'.

  17. The Effect of Hip Bracing on Gait in Patients with Medial Knee Osteoarthritis

    David Wallace; Christa Barr

    2012-01-01

    Objective. Impaired hip motion has been associated with heightened medial knee joint loading in patients with knee osteoarthritis (OA). A hip external rotation strap designed to pull the femur into external rotation and abduction may serve as one protective mechanism. The primary aim of our study is to determine if the strap decreases medial knee joint loading during level walking in people with knee OA. Design. This study is a single-day repeated measures design. Methods. 15 volunteers with ...

  18. Muscle activity during knee-extension strengthening exercise performed with elastic tubing and isotonic resistance

    Jakobsen, Markus Due; Sundstrup, Emil; Andersen, Christoffer H;

    2012-01-01

    While elastic resistance training, targeting the upper body is effective for strength training, the effect of elastic resistance training on lower body muscle activity remains questionable. The purpose of this study was to evaluate the EMG-angle relationship of the quadriceps muscle during 10-RM ...

  19. Muscle activity during knee-extension strengthening exercise performed with elastic tubing and isotonic resistance

    Jakobsen, Markus Due; Sundstrup, Emil; Andersen, Christoffer H;

    2012-01-01

    BACKGROUND/PURPOSE: While elastic resistance training, targeting the upper body is effective for strength training, the effect of elastic resistance training on lower body muscle activity remains questionable. The purpose of this study was to evaluate the EMG-angle relationship of the quadriceps ...

  20. Functional calibration procedure for 3D knee joint angle description using inertial sensors.

    Favre, J; Aissaoui, R; Jolles, B M; de Guise, J A; Aminian, K

    2009-10-16

    Measurement of three-dimensional (3D) knee joint angle outside a laboratory is of benefit in clinical examination and therapeutic treatment comparison. Although several motion capture devices exist, there is a need for an ambulatory system that could be used in routine practice. Up-to-date, inertial measurement units (IMUs) have proven to be suitable for unconstrained measurement of knee joint differential orientation. Nevertheless, this differential orientation should be converted into three reliable and clinically interpretable angles. Thus, the aim of this study was to propose a new calibration procedure adapted for the joint coordinate system (JCS), which required only IMUs data. The repeatability of the calibration procedure, as well as the errors in the measurement of 3D knee angle during gait in comparison to a reference system were assessed on eight healthy subjects. The new procedure relying on active and passive movements reported a high repeatability of the mean values (offset0.9). In comparison to the reference system, this functional procedure showed high precision (SD0.75) and moderate accuracy (between 4.0 degrees and 8.1 degrees) for the three knee angle. The combination of the inertial-based system with the functional calibration procedure proposed here resulted in a promising tool for the measurement of 3D knee joint angle. Moreover, this method could be adapted to measure other complex joint, such as ankle or elbow.

  1. Design and testing a web-based physical activity intervention for patients with osteoarthritis in hip and/or knee.

    Bossen, D.

    2012-01-01

    Purpose: Due to elevated fear of pain, catastrophizing thoughts and joint stiffness, a large group of patients with hip and/or knee osteoarthritis (OA) remain sedentary. Although inactivity may enhance in short-term pain reduction, prolonged inactivity may augment functional decline. Therefore, we d

  2. Knees Lifted High

    2008-08-04

    The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Knees Lifted High gives children fun ideas for active outdoor play.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

  3. Stiffness after total knee arthroplasty.

    Manrique, Jorge; Gomez, Miguel M; Parvizi, Javad

    2015-04-01

    Stiffness after total knee arthroplasty (TKA) adversely affects outcome and impacts patient function. Various risk factors for stiffness after TKA have been identified, including reduced preoperative knee range of motion, history of prior knee surgery, etiology of arthritis, incorrect positioning or oversizing of components, and incorrect gap balancing. Mechanical and associated causes, such as infection, arthrofibrosis, complex regional pain syndrome, and heterotopic ossification, secondary gain issues have also been identified. Management of stiffness following TKA can be challenging. The condition needs to be assessed and treated in a staged manner. A nonsurgical approach is the first step. Manipulation under anesthesia may be considered within the first 3 months after the index TKA, if physical therapy fails to improve the range of motion. Beyond this point, consideration should be given to surgical intervention such as lysis of adhesions, either arthroscopically or by open arthrotomy. If the cause of stiffness is deemed to be surgical error, such as component malpositioning, revision arthroplasty is indicated. The purpose of this article is to evaluate the various aspects of management of stiffness after TKA.

  4. Early recovery after fast-track Oxford unicompartmental knee arthroplasty

    Munk, Stig; Dalsgaard, Jesper; Bjerggaard, Karin

    2012-01-01

    trauma. We investigated changes in leg-extension power (LEP) in the first month after MIS Oxford UKA and its relation to pain, knee motion, functional performance, and knee function. Patients and methods In 35 consecutive Oxford UKA patients, LEP was measured 1 week before and 1 month after surgery...... supervision in the first month after discharge. Interpretation Fast-track MIS Oxford UKA with discharge on the day after surgery is safe and leads to early recovery of knee motion and strength even when no physiotherapy is used....

  5. Prediction of near-field strong ground motions for scenario earthquakes on active fault

    Wang Haiyun; Xie Lili; Tao Xiaxin; Li Jie

    2006-01-01

    A method to predict near-field strong ground motions for scenario earthquakes on active faults is proposed. First,macro-source parameters characterizing the entire source area, i.e., global source parameters, including fault length, fault width,rupture area, average slip on the fault plane, etc., are estimated by seismogeology survey, seismicity and seismic scaling laws.Second, slip distributions characterizing heterogeneity or roughness on the fault plane, i.e., local source parameters, are reproduced/evaluated by the hybrid slip model. Finally, the finite fault source model, developed from both the global and local source parameters, is combined with the stochastically synthetic technique of ground motion using the dynamic corner frequency based on seismology. The proposed method is applied to simulate the acceleration time histories on three base-rock stations during the 1994 Northridge earthquake. Comparisons between the predicted and recorded acceleration time histories show that the method is feasible and practicable.

  6. A kinematic comparison of alterations to knee and ankle angles from resting measures to active pedaling during a graded exercise protocol.

    Peveler, Willard W; Shew, Brandy; Johnson, Samantha; Palmer, Thomas G

    2012-11-01

    Saddle height is one of the most researched areas of bike fit. The current accepted method for adjusting saddle height involves the use of a goniometer to adjust saddle height so that a knee angle between 25° and 35° is obtained. This measurement is taken while the cyclist maintains a static position with the pedal at the 6-o'-clock position. However, the act of pedaling is dynamic, and angles may alter during movement. The purpose of this study was to examine the alterations to knee and ankle angle occurring from static measures to active pedaling across intensities experienced by cyclists during a graded exercise protocol. Thirty-four recreational to highly trained cyclists were evaluated using 2D analysis of stationary position and 3 active levels (level 1, respiratory exchange ratio of 1.00, and max). Dependent measures were compared using repeated measures analysis of variance (p = 0.05). When examining the results, it is evident that significant alterations to pedal stroke occur from stationary measures to active pedaling and as intensity increases toward maximal. Plantar flexion increased when moving from stationary measures to active pedaling, which resulted in an increase in knee angle. Although still greater than stationary measures, less plantar flexion occurred at higher intensities when compared with lower intensity cycling. Less plantar flexion at higher intensities is most likely a result of application of a larger downward torque occurring because of greater power requirements at higher intensities. There appeared to be greater variability in angle when examining novice cyclists in relation to more experienced cyclists. Although stationary measures are where a bike fit session will begin, observation during the pedal cycle may be needed to fine-tune the riders' fit.

  7. Multiple-ligament injured knee

    SUN Lei; NING Zhi-jie; ZHANG Hui; TIAN Min; NING Tin-min

    2006-01-01

    Objective: To explore the clinical characteristic of the multiple-ligament injured knee and evaluate the protocol,technique and outcome of treatment for the multipleligament injured knee.Methods: From October 2001 to March 2005, 9 knees with combined anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) tears in 9 patients were identified with clinical and arthroscopic examinations. Of them, 5 knees were combined with ruptures of posteromedial corner (PMC) and medial collateral ligament (MCL), 4 with disruptions of posterolateral corner ( PLC), 2 with popliteal vascular injuries and 1 with peroneal nerve injuries. Six patients were hospitalized in acute phase of trauma, 2 received repairs of popliteal artery and 4 had repairs of PMC and MCL. Reconstructions of ACL and PCL with autografts under arthroscope were performed in all patients at 4 to 10 weeks after trauma,including reconstruction of PLC with the posterior half of biceps femoris tendon tenodesis in 4 patients and reconstructions of PMC and MCL with femoral fascia in 1 patient.Results: No severe complications occurred at early stage after operation in the 9 patients. All of them were followed up for 10-39 months with an average of 23. 00 months ± 9.46 months. Lysholm score was 70-95 with an average of 85.00 ± 8.29. International Knee Documentation Committee (IKDC) score was from severely abnormal (Grade D) in 9 knees at initial examination to normal (Grade A) in 2 knees, nearly normal (Grade B ) in 6 knees and abnormal in 1 knee at the last follow-up. Of the 9 patients, 7 returned to the same activity level before injury and 2 were under the level.Conclusions: The multiple-ligament injured knee with severe instability is usually combined with other important structure damages. Therefore, careful assessment and treatment of the combined injuries are essential. Reconstructions of ACL and PCL under arthroscope, combined with repairs or reconstructions of the extraarticular ligaments

  8. Arm position influences the activation patterns of trunk muscles during trunk range-of-motion movements.

    Siu, Aaron; Schinkel-Ivy, Alison; Drake, Janessa Dm

    2016-10-01

    To understand the activation patterns of the trunk musculature, it is also important to consider the implications of adjacent structures such as the upper limbs, and the muscles that act to move the arms. This study investigated the effects of arm positions on the activation patterns and co-activation of the trunk musculature and muscles that move the arm during trunk range-of-motion movements (maximum trunk axial twist, flexion, and lateral bend). Fifteen males and fifteen females, asymptomatic for low back pain, performed maximum trunk range-of-motion movements, with three arm positions for axial twist (loose, crossed, abducted) and two positions for flexion and lateral bend (loose, crossed). Electromyographical data were collected for eight muscles bilaterally, and activation signals were cross-correlated between trunk muscles and the muscles that move the arms (upper trapezius, latissimus dorsi). Results revealed consistently greater muscle co-activation (higher cross-correlation coefficients) between the trunk muscles and upper trapezius for the abducted arm position during maximum trunk axial twist, while results for the latissimus dorsi-trunk pairings were more dependent on the specific trunk muscles (either abdominal or back) and latissimus dorsi muscle (either right or left side), as well as the range-of-motion movement. The findings of this study contribute to the understanding of interactions between the upper limbs and trunk, and highlight the influence of arm positions on the trunk musculature. In addition, the comparison of the present results to those of individuals with back or shoulder conditions may ultimately aid in elucidating underlying mechanisms or contributing factors to those conditions.

  9. Time-driven Activity-based Cost of Fast-Track Total Hip and Knee Arthroplasty

    Andreasen, Signe E.; Holm, Henriette B; Jørgensen, Mira

    2016-01-01

    this between 2 departments with different logistical set-ups. METHODS: Prospective data collection was analyzed using the time-driven activity-based costing method (TDABC) on time consumed by different staff members involved in patient treatment in the perioperative period of fast-track THA and TKA in 2 Danish......-track methodology, the result could be a more cost-effective pathway altogether. As THA and TKA are potentially costly procedures and the numbers are increasing in an economical limited environment, the aim of this study is to present baseline detailed economical calculations of fast-track THA and TKA and compare...... orthopedic departments with standardized fast-track settings, but different logistical set-ups. RESULTS: Length of stay was median 2 days in both departments. TDABC revealed minor differences in the perioperative settings between departments, but the total cost excluding the prosthesis was similar at USD...

  10. The Use of the Matrix Method for the Study of Human Motion:Theory and Applications

    Zong-Ming Li; Jesse A. Fisk; Savio L-Y. Woo

    2003-01-01

    Kinematics has been successfully used to describe body motion without reference to the kinetics (or forces causing the motion). In this article, both the theory and applications of the matrix method are provided to describe complex human motion. After the definition of a Cartesian coordinate frame is introduced, the description of transformations between multiple coordinate frames is given; the decomposition of a transformation matrix into anatomical joint motion parameters (e.g. Euler angles) is then explained. The advantages of the matrix method are illustrated by three examples related to biomechanical studies. The first describes a reaching and grasping task in which matrix transformations are applied to position the hand with respect to an object during grasping. The second example demonstrates the utility of the matrix method in revealing the coupling motion of the wrist between flexion-extension and radial-ulnar deviation. The last example highlights the indispensable use of the matrix method for the study of knee biomechanics, including the description of knee joint kinematics during functional activities and determination of in-situ ligament forces using robotic technology, which has advanced our understanding of the functions of the cruciate ligaments to knee joint kinematics. It is hoped that the theoretical development and biomechanical application examples will help the readers apply the matrix method to research problems related to human motion.

  11. Impact of Physical Activity in Cardiovascular and Musculoskeletal Health: Can Motion Be Medicine?

    Curtis, Gannon L.; Chughtai, Morad; Khlopas, Anton; Newman, Jared M.; Khan, Rafay; Shaffiy, Shervin; Nadhim, Ali; Bhave, Anil; Mont, Michael A.

    2017-01-01

    Physical activity is a well-known therapeutic tool for various types of medical conditions, including vasculopathic diseases such as coronary artery disease, stroke, type 2 diabetes, and obesity. Additionally, increased physical activity has been proposed as a therapy to improve musculoskeletal health; however, there are conflicting reports about physical activity potentially leading to degenerative musculoskeletal disease, especially osteoarthritis (OA). Additionally, although physical activity is known to have its benefits, it is unclear as to what amount of physical activity is the most advantageous. Too much, as well as not enough exercise can have negative consequences. This could impact how physicians advise their patients about exercise intensity. Multiple studies have evaluated the effect of physical activity on various aspects of health. However, there is a paucity of systematic studies which review cardiovascular and musculoskeletal health as outcomes. Therefore, the purpose of this review was to assess how physical activity impacts these aspects of health. Specifically, we evaluated the effect of various levels of physical activity on: 1) cardiovascular and 2) musculoskeletal health. The review revealed that physical activity may decrease cardiovascular disease and improve OA symptoms, and therefore, motion can be considered a “medicine”. However, because heavy activity can potentially lead to increased OA risk, physicians should advise their patients that excessive activity can also potentially impact their health negatively, and should be done in moderation, until further study.

  12. Modeling meiotic chromosome pairing: nuclear envelope attachment, telomere-led active random motion, and anomalous diffusion

    Marshall, Wallace F.; Fung, Jennifer C.

    2016-04-01

    The recognition and pairing of homologous chromosomes during meiosis is a complex physical and molecular process involving a combination of polymer dynamics and molecular recognition events. Two highly conserved features of meiotic chromosome behavior are the attachment of telomeres to the nuclear envelope and the active random motion of telomeres driven by their interaction with cytoskeletal motor proteins. Both of these features have been proposed to facilitate the process of homolog pairing, but exactly what role these features play in meiosis remains poorly understood. Here we investigate the roles of active motion and nuclear envelope tethering using a Brownian dynamics simulation in which meiotic chromosomes are represented by a Rouse polymer model subjected to tethering and active forces at the telomeres. We find that tethering telomeres to the nuclear envelope slows down pairing relative to the rates achieved by unattached chromosomes, but that randomly directed active forces applied to the telomeres speed up pairing dramatically in a manner that depends on the statistical properties of the telomere force fluctuations. The increased rate of initial pairing cannot be explained by stretching out of the chromosome conformation but instead seems to correlate with anomalous diffusion of sub-telomeric regions.

  13. Activity preferences, lifestyle modifications and re-injury fears influence longer-term quality of life in people with knee symptoms following anterior cruciate ligament reconstruction: a qualitative study

    Stephanie R Filbay

    2016-04-01

    Full Text Available Questions: How do people with knee symptoms describe their quality of life and experiences 5 to 20 years after anterior cruciate ligament reconstruction (ACLR? What factors impact upon the quality of life of these people? Design: Qualitative study. Participants: Seventeen people with knee symptoms 5 to 20 years after ACLR and high (n = 8 or low (n = 9 quality of life scores were recruited from a cross-sectional study. Methods: Semi-structured telephone interviews were conducted and transcribed. The data obtained from the interventions underwent inductive coding and thematic analysis. Results: Four consistent themes emerged from the interviews as common determinants of quality of life following ACLR: physical activity preferences; lifestyle modifications; adaptation and acceptance; and fear of re-injury. All participants described the importance of maintaining a physically active lifestyle and the relationship between physical activity and quality of life. Participants who avoided sport or activity reported experiencing reduced quality of life. Participants who suppressed or overcame re-injury fears to continue sport participation described experiencing a satisfactory quality of life while taking part in sport despite knee symptoms. For some participants, resuming competitive sport resulted in subsequent knee trauma, anterior cruciate ligament re-rupture or progressive deterioration of knee function, with negative impacts on quality of life following sport cessation. Participants who enjoyed recreational exercise often adapted their lifestyle early after ACLR, while others described adapting their lifestyle at a later stage to accommodate knee impairments; this was associated with feelings of acceptance and satisfaction, irrespective of knee symptoms. Conclusion: Activity preferences, lifestyle modifications and fear of re-injury influenced quality of life in people with knee symptoms up to 20 years following ACLR. People with a preference

  14. Development of Kinematic Graphs of Median Nerve during Active Finger Motion: Implications of Smartphone Use.

    Hoi-Chi Woo

    Full Text Available Certain hand activities cause deformation and displacement of the median nerve at the carpal tunnel due to the gliding motion of tendons surrounding it. As smartphone usage escalates, this raises the public's concern whether hand activities while using smartphones can lead to median nerve problems.The aims of this study were to 1 develop kinematic graphs and 2 investigate the associated deformation and rotational information of median nerve in the carpal tunnel during hand activities.Dominant wrists of 30 young adults were examined with ultrasonography by placing a transducer transversely on their wrist crease. Ultrasound video clips were recorded when the subject performing 1 thumb opposition with the wrist in neutral position, 2 thumb opposition with the wrist in ulnar deviation and 3 pinch grip with the wrist in neutral position. Six still images that were separated by 0.2-second intervals were then captured from the ultrasound video for the determination of 1 cross-sectional area (CSA, 2 flattening ratio (FR, 3 rotational displacement (RD and 4 translational displacement (TD of median nerve in the carpal tunnel, and these collected information of deformation, rotational and displacement of median nerve were compared between 1 two successive time points during a single hand activity and 2 different hand motions at the same time point. Finally, kinematic graphs were constructed to demonstrate the mobility of median nerve during different hand activities.Performing different hand activities during this study led to a gradual reduction in CSA of the median nerve, with thumb opposition together with the wrist in ulnar deviation causing the greatest extent of deformation of the median nerve. Thumb opposition with the wrist in ulnar deviation also led to the largest extent of TD when compared to the other two hand activities of this study. Kinematic graphs showed that the motion pathways of median nerve during different hand activities were complex

  15. Conceptualization of an exoskeleton Continuous Passive Motion(CPM) device using a link structure.

    Kim, Kyu-Jung; Kang, Min-Sung; Choi, Youn-Sung; Han, Jungsoo; Han, Changsoo

    2011-01-01

    This study is about developing an exoskeleton Continuous Passive Motion (CPM) with the same Range of Motion (ROM) and instant center of rotation as the human knee. The key feature in constructing a CPM is an accurate alignment with the human knee joint enabling it to deliver the same movements as the actual body on the CPM. In this research, we proposed an exoskeleton knee joint through kinematic interpretation, measured the knee joint torque generated while using a CPM and applied it to the device. Thus, this new exoskeleton type CPM will allow precise alignment with the human knee joint, and follow the same ROM as the human knee in any position.

  16. Active range of motion outcomes after reconstruction of burned wrist and hand deformities.

    Afifi, Ahmed M; Mahboub, Tarek A; Ibrahim Fouad, Amr; Azari, Kodi; Khalil, Haitham H; McCarthy, James E

    2016-06-01

    This works aim is to evaluate the efficacy of skin grafts and flaps in reconstruction of post-burn hand and wrist deformities. A prospective study of 57 burn contractures of the wrist and dorsum of the hand was performed. Flaps were used only if there was a non-vascularized structure after contracture release, otherwise a skin graft was used. Active range of motion (ROM) was used to assess hand function. The extension deformity cohort uniformly underwent skin graft following contracture release with a mean improvement of 71 degrees (p6 months. Early release of burn contracture is advisable to avoid deep structure contracture.

  17. Loss of knee-extension strength is related to knee swelling after total knee arthroplasty

    Holm, Bente; Kristensen, Morten T; Bencke, Jesper;

    2010-01-01

    To examine whether changes in knee-extension strength and functional performance are related to knee swelling after total knee arthroplasty (TKA).......To examine whether changes in knee-extension strength and functional performance are related to knee swelling after total knee arthroplasty (TKA)....

  18. Microprocessor prosthetic knees.

    Berry, Dale

    2006-02-01

    This article traces the development of microprocessor prosthetic knees from early research in the 1970s to the present. Read about how microprocessor knees work, functional options, patient selection, and the future of this prosthetic.

  19. Prosthetic Knee Systems

    ... us Digg Facebook Google Bookmarks Technorati Yahoo MyWeb Prosthetic Knee Systems Translated into plain language by Helen ... Health Literacy Consulting Original article by Bill Dupes Prosthetic knee systems are among the most complex of ...

  20. Partial knee replacement - slideshow

    ... page: //medlineplus.gov/ency/presentations/100225.htm Partial knee replacement - series—Normal anatomy To use the sharing ... A.M. Editorial team. Related MedlinePlus Health Topics Knee Replacement A.D.A.M., Inc. is accredited ...

  1. Knee braces - unloading

    ... most people talk about the arthritis in their knees, they are referring to a type of arthritis ... is caused by wear and tear inside your knee joints. Cartilage, the firm, rubbery tissue that cushions ...

  2. Knee arthroscopy - slideshow

    ... this page: //medlineplus.gov/ency/presentations/100117.htm Knee arthroscopy - series—Normal anatomy To use the sharing ... to slide 5 out of 5 Overview The knee is a complex joint made up of the ...

  3. Knee joint replacement - slideshow

    ... this page: //medlineplus.gov/ency/presentations/100088.htm Knee joint replacement - series—Normal anatomy To use the ... to slide 4 out of 4 Overview The knee is a complex joint. It contains the distal ...

  4. Relationship between active cervical range of motion and flexion-relaxation ratio in asymptomatic computer workers.

    Yoo, Won-Gyu; Park, Se-Yeon; Lee, Mi-Ra

    2011-01-01

    A high prevalence and incidence of neck and shoulder pain is present in the working population, especially sedentary workers. Recent findings have indicated that the flexion-relaxation (FR) ratio in the cervical erector spinae (CES) muscles might be a significant criteria of neuromuscular impairment and function. Additionally, the active cervical range of motion (ROM) is frequently used for discriminating between individuals with pain and those who are asymptomatic. The purpose of the present study was to examine the relationship between the active cervical ROM and the FR ratio in a sample of regular visual display terminal (VDT) workers. In total, 20 asymptomatic male VDT workers were recruited. Active cervical ROM was measured by a cervical ROM (CROM) instrument. Surface electromyography (EMG) was used to collect myoelectrical signals from the CES muscles, and the FR ratio was calculated for statistical analysis. Pearson correlation coefficients were used to quantify the linear relationship between the active cervical ROM and the FR ratio. The values obtained for the FR ratio in the right CES muscles correlated significantly with the active cervical ROM measured in flexion (r=0.73, pcervical FR ratio had a positive correlation with cervical movements, and that changes of the activation patterns in CES demonstrated as cervical FR ratio are associated with reduction of the cervical range of motion including flexion and lateral flexion. In addition, muscular dysfunction of the CES could occur in regular computer workers prior to occurrence of pain; this means that the FR ratio could be used to evaluate the potential risk of neck discomfort in computer workers.

  5. Total Knee Arthroplasty in the Combined Contracture

    O.J. Voskresensky

    2009-09-01

    Full Text Available We have offered modified access to a knee to work out a method for restoration of extensive apparatus of the knee. 91 patients with degenerative damages of the knee were under out su-pervision. All patients were differentiated in groups according to the form of access and pa-thology of the knee. At all stages of studying the following method of investigation were made: goniometry — for estimation of the knee functional condition; electroneiromyography — for reveling deficiency of muscular activity and determination of its kind. Patient's satisfac-tion by operation was defined by means of WOMAC scale subjective indexes. The received digital material was subjected to statistical processing. Thus, it has been proved that applica-tion of the modified access to a knee offered by us in total knee arthroplasty in patients with combined contracture in comparison with traditionally applied technologies of extensive ap-paratus releasing allows in short terms to restore the volume and force of movements in a knee that reduces time of rehabilitation and improves quality of patient's life

  6. Perceived Direction of Self-Motion from Orthogonally Directed Visual and Vestibular Stimulation in Passive and Active Observation

    Kenzo Sakurai

    2011-10-01

    Full Text Available Perceiving the direction of self-motion is typically a multisensory process. The most effective cue to detect the observer's heading direction is the visual optic-flow pattern. In the initial period of body movement, however, the vestibular sense is another effective cue to detect the direction in which one's body started to move. Here I report our recent research on the perception of self-motion, 1 when observers are passively experiencing their real somatic motion in different body posture, and 2 when observers are actively moving their bodies forward and backward. Previously, we reported that when upright observers passively experience real linear oscillatory somatic motion (leftward/rightward or forward/backward while viewing orthogonal visual optic flow patterns (translating or expanding/contracting, their perceived body motion direction is intermediate to those specified by visual and vestibular information individually (Sakurai et al., 2002, ACV; 2003, ECVP; Sakurai et al., 2010, VSS; Kubodera et al., 2010, APCV. We then generalized those findings exploring other visual/vestibular combinations, investigating when the vertical axis of body coordinates is orthogonal to the gravity axis. Observers lay supinely and reported their perceived direction of self-motion, experiencing real upward/downward or leftward/rightward motion in body coordinates, while viewing orthogonal optic-flow patterns that were phase-locked to the swing motion. The results are very similar to our previous reports, but for combinations of body motion with visual expanding/contracting optic-flow, some observers' judgments were vision-only or vestibular-only, suggesting that multimodal integration in this context is an either-or process for these observers. Compared to our previous reports, one possible reason for this weighted combination failure is the discrepancy between body coordinates and gravity coordinates (Sakurai et al., 2011, ECVP. We recently extended those

  7. Increased sensitivity to physical activity among individuals with knee osteoarthritis: relation to pain outcomes, psychological factors, and responses to quantitative sensory testing.

    Wideman, Timothy H; Finan, Patrick H; Edwards, Robert R; Quartana, Phillip J; Buenaver, Luis F; Haythornthwaite, Jennifer A; Smith, Michael T

    2014-04-01

    Recent findings suggest that certain individuals with musculoskeletal pain conditions have increased sensitivity to physical activity (SPA) and respond to activities of stable intensity with increasingly severe pain. This study aimed to determine the degree to which individuals with knee osteoarthritis (OA) show heightened SPA in response to a standardized walking task and whether SPA cross-sectionally predicts psychological factors, responses to quantitative sensory testing (QST), and different OA-related outcomes. One hundred seven adults with chronic knee OA completed self-report measures of pain, function, and psychological factors, underwent QST, and performed a 6-min walk test. Participants rated their discomfort levels throughout the walking task; an index of SPA was created by subtracting first ratings from peak ratings. Repeated-measure analysis of variance revealed that levels of discomfort significantly increased throughout the walking task. A series of hierarchical regression analyses determined that after controlling for significant covariates, psychological factors, and measures of mechanical pain sensitivity, individual variance in SPA predicted self-report pain and function and performance on the walking task. Analyses also revealed that both pain catastrophizing and the temporal summation of mechanical pain were significant predictors of SPA and that SPA mediated the relationship between catastrophizing and self-reported pain and physical function. The discussion addresses the potential processes contributing to SPA and the role it may play in predicting responses to different interventions for musculoskeletal pain conditions.

  8. Biomechanical analysis of stair descent in patients with knee osteoarthritis.

    Igawa, Tatsuya; Katsuhira, Junji

    2014-05-01

    [Purpose] The purposes of this study were to investigate the lower extremity joint kinematics and kinetics of patients with the knee osteoarthritis (knee OA) during stair descent and clarify the biomechanical factors related to their difficulty in stair descent. [Subjects and Methods] Eight healthy elderly persons and four knee OA patients participated in this study. A 3-D motion analysis system and force plates were employed to measure lower extremity joint angles, ranges of motion, joint moments, joint powers, and ratios of contribution for the joint powers while descending stairs. [Results] Knee joint flexion angle, extension moment, and negative power during the early stance phase in the knee OA group were smaller than those in the healthy subjects group. However, no significant changes in these parameters in the ankle joint were observed between the two subject groups. [Conclusion] Knee OA patients could not use the knee joint to absorb impact during the early stance phase of stair descent. Hence, they might compensate for the roles played by the intact knee joint by mainly using ipsilateral ankle kinematics and kinetics.

  9. Semi-active control of the rocking motion of monolithic art objects

    Ceravolo, Rosario; Pecorelli, Marica Leonarda; Zanotti Fragonara, Luca

    2016-07-01

    The seismic behaviour of many art objects and obelisks can be analysed in the context of the seismic response of rigid blocks. Starting from the pioneering works by Housner, a large number of analytical studies of the rigid block dynamics were proposed. In fact, despite its apparent simplicity, the motion of a rigid block involves a number of complex dynamic phenomena such as impacts, sliding, uplift and geometric nonlinearities. While most of the current strategies to avoid toppling consist in preventing rocking motion, in this paper a novel semi-active on-off control strategy for protecting monolithic art objects was investigated. The control procedure under study follows a feedback-feedforward scheme that is realised by switching the stiffness of the anchorages located at the two lower corner of the block between two values. Overturning spectra have been calculated in order to clarify the benefits of applying a semi-active control instead of a passive control strategy. In accordance with similar studies, the numerical investigation took into account the dynamic response of blocks with different slenderness and size subject to one-sine pulse excitation.

  10. Traumatic knee extension deficit (the locked knee)

    Helmark, I C; Neergaard, K; Krogsgaard, M R

    2007-01-01

    In the present study we investigated the validity of magnetic resonance imaging (MRI) and arthroscopy in knees with acute, traumatic extension deficit (the "locked knee"), and evaluated whether arthroscopy of knees with no mechanical pathology could be avoided by MRI evaluation. The study consisted...... of 50 patients who had an acute, traumatic extension deficit of the knee. All patients were submitted to MRI prior to arthroscopy. Following MRI and surgery, standardized forms were filled out, attempting to objectify the findings. The orthopaedic surgeon was not aware of the MRI result prior to surgery......, the following results were calculated for the overall appearance of a lesion able to cause locking: Positive predictive value = 0.85, negative predictive value = 0.77, sensitivity = 0.95, specificity = 0.53. Two knees were erroneously evaluated with no mechanical locking at MRI (one bucket-handle lesion and one...

  11. Knee Arthrodesis after failure of Knee Arthroplasty

    Gottfriedsen, Tinne B; Morville Schrøder, Henrik; Odgaard, Anders

    2016-01-01

    BACKGROUND: Arthrodesis is considered a salvage procedure after failure of a knee arthroplasty. Data on the use of this procedure are limited. The purpose of this study was to identify the incidence, causes, surgical techniques, and outcomes of arthrodesis after failed knee arthroplasty...... in a nationwide population. METHODS: Data were extracted from the Danish Civil Registration System, the Danish National Patient Register, and the Danish Knee Arthroplasty Register. A total of 92,785 primary knee arthroplasties performed in Denmark from 1997 to 2013 were identified by linking the data using....... Differences in cumulative incidence were compared with the Gray test. RESULTS: A total of 164 of the 165 arthrodeses were performed for causes related to failed knee arthroplasty. The 15-year cumulative incidence of arthrodesis was 0.26% (95% confidence interval, 0.21% to 0.31%). The 5-year cumulative...

  12. Multibody dynamic simulation of knee contact mechanics.

    Bei, Yanhong; Fregly, Benjamin J

    2004-11-01

    Multibody dynamic musculoskeletal models capable of predicting muscle forces and joint contact pressures simultaneously would be valuable for studying clinical issues related to knee joint degeneration and restoration. Current three-dimensional multibody knee models are either quasi-static with deformable contact or dynamic with rigid contact. This study proposes a computationally efficient methodology for combining multibody dynamic simulation methods with a deformable contact knee model. The methodology requires preparation of the articular surface geometry, development of efficient methods to calculate distances between contact surfaces, implementation of an efficient contact solver that accounts for the unique characteristics of human joints, and specification of an application programming interface for integration with any multibody dynamic simulation environment. The current implementation accommodates natural or artificial tibiofemoral joint models, small or large strain contact models, and linear or nonlinear material models. Applications are presented for static analysis (via dynamic simulation) of a natural knee model created from MRI and CT data and dynamic simulation of an artificial knee model produced from manufacturer's CAD data. Small and large strain natural knee static analyses required 1 min of CPU time and predicted similar contact conditions except for peak pressure, which was higher for the large strain model. Linear and nonlinear artificial knee dynamic simulations required 10 min of CPU time and predicted similar contact force and torque but different contact pressures, which were lower for the nonlinear model due to increased contact area. This methodology provides an important step toward the realization of dynamic musculoskeletal models that can predict in vivo knee joint motion and loading simultaneously.

  13. Submaximal fatigue of the hamstrings impairs specific reflex components and knee stability.

    Melnyk, Mark; Gollhofer, Albert

    2007-05-01

    Rupture of the anterior cruciate ligament (ACL) is one of the most serious sports-related injuries and requires long recovery time. The quadriceps and hamstring muscles are functionally important to control stability of the knee joint complex. Fatigue, however, is an important factor that may influence stabilizing control and thus cause ACL injuries. The objective of this study was therefore to assess how submaximal fatigue exercises of the hamstring muscles affect anterior tibial translation as a direct measure of knee joint stability. While 15 test participants were standing upright with the knees in 30 degrees of flexion, anterior tibial translation was induced by a force of 315 N. Two linear potentiometers placed on the tibial tuberosity and the patella recorded tibial motion relative to the femur. Reflex latencies and neuromuscular hamstring activity were determined using surface electromyography (EMG). Muscle fatigue produced a significant longer latency for the monosynaptic reflex latencies, whereas no differences in the latencies of the medium latency component were found. Fatigue significantly reduced EMG amplitudes of the short and medium latency components. These alterations were in line with significantly increased anterior tibial translation. Our results suggest that hamstring fatigue is effectively associated with mechanical loss of knee stability. This decrease in joint stability may at least in part explain higher risk of ACL injury, especially in fatigued muscles. Furthermore, we discuss why the present findings indicate that reduced motor activity rather than the extended latency of the first hamstring response is the reason for possible failure.

  14. Evaluating knee replacement mechanics during ADL with PID-controlled dynamic finite element analysis.

    Fitzpatrick, Clare K; Baldwin, Mark A; Clary, Chadd W; Maletsky, Lorin P; Rullkoetter, Paul J

    2014-01-01

    Validated computational knee simulations are valuable tools for design phase development of knee replacement devices. Recently, a dynamic finite element (FE) model of the Kansas knee simulator was kinematically validated during gait and deep flexion cycles. In order to operate the computational simulator in the same manner as the experiment, a proportional-integral-derivative (PID) controller was interfaced with the FE model to control the quadriceps actuator excursion and produce a target flexion profile regardless of implant geometry or alignment conditions. The controller was also expanded to operate multiple actuators simultaneously in order to produce in vivo loading conditions at the joint during dynamic activities. Subsequently, the fidelity of the computational model was improved through additional muscle representation and inclusion of relative hip-ankle anterior-posterior (A-P) motion. The PID-controlled model was able to successfully recreate in vivo loading conditions (flexion angle, compressive joint load, medial-lateral load distribution or varus-valgus torque, internal-external torque, A-P force) for deep knee bend, chair rise, stance-phase gait and step-down activities.

  15. Effect of motion smoothness on brain activity while observing a dance: An fMRI study using a humanoid robot.

    Miura, Naoki; Sugiura, Motoaki; Takahashi, Makoto; Sassa, Yuko; Miyamoto, Atsushi; Sato, Shigeru; Horie, Kaoru; Nakamura, Katsuki; Kawashima, Ryuta

    2010-01-01

    Motion smoothness is critical in transmitting implicit information of body action, such as aesthetic qualities in dance performances. We expected that the perception of motion smoothness would be characterized by great intersubject variability deriving from differences in personal backgrounds and attitudes toward expressive body actions. We used functional magnetic resonance imaging and a humanoid robot to investigate the effects of the motion smoothness of expressive body actions and the intersubject variability due to personal attitudes on perceptions during dance observation. The effect of motion smoothness was analyzed by both conventional subtraction analysis and functional connectivity analyses that detect cortical networks reflecting intersubject variability. The results showed that the cortical networks of motion- and body-sensitive visual areas showed increases in activity in areas corresponding with motion smoothness, but the intersubject variability of personal attitudes toward art did not influence these active areas. In contrast, activation of cortical networks, including the parieto-frontal network, has large intersubject variability, and this variability is associated with personal attitudes about the consciousness of art. Thus, our results suggest that activity in the cortical network involved in understanding action is influenced by personal attitudes about the consciousness of art during observations of expressive body actions.

  16. Anterior knee pain

    LLopis, Eva [Hospital de la Ribera, Alzira, Valencia (Spain) and Carretera de Corbera km 1, 46600 Alzira Valencia (Spain)]. E-mail: ellopis@hospital-ribera.com; Padron, Mario [Clinica Cemtro, Ventisquero de la Condesa no. 42, 28035 Madrid (Spain)]. E-mail: mario.padron@clinicacemtro.com

    2007-04-15

    Anterior knee pain is a common complain in all ages athletes. It may be caused by a large variety of injuries. There is a continuum of diagnoses and most of the disorders are closely related. Repeated minor trauma and overuse play an important role for the development of lesions in Hoffa's pad, extensor mechanism, lateral and medial restrain structures or cartilage surface, however usually an increase or change of activity is referred. Although the direct relation of cartilage lesions, especially chondral, and pain is a subject of debate these lesions may be responsible of early osteoarthrosis and can determine athlete's prognosis. The anatomy and biomechanics of patellofemoral joint is complex and symptoms are often unspecific. Transient patellar dislocation has MR distinct features that provide evidence of prior dislocation and rules our complication. However, anterior knee pain more often is related to overuse and repeated minor trauma. Patella and quadriceps tendon have been also implicated in anterior knee pain, as well as lateral or medial restraint structures and Hoffa's pad. US and MR are excellent tools for the diagnosis of superficial tendons, the advantage of MR is that permits to rule out other sources of intraarticular derangements. Due to the complex anatomy and biomechanic of patellofemoral joint maltracking is not fully understood; plain films and CT allow the study of malalignment, new CT and MR kinematic studies have promising results but further studies are needed. Our purpose here is to describe how imaging techniques can be helpful in precisely defining the origin of the patient's complaint and thus improve understanding and management of these injuries.

  17. Association of Cross Linked C-Telopeptide II Collagen and Hyaluronic Acid with Knee Osteoarthritis Severity

    John Butar Butar

    2013-12-01

    Full Text Available BACKGROUND: This study was carried out to investigate the association of Cross Linked C-Telopeptide Type I & II Collagen (CTX-I and II and hyaluronic acid (HA with knee osteoarthritis (OA severity. METHODS: Sixty menopause women with primary knee OA were enrolled in this study during their visits to the Outpatient Department. Patients with knee pain during weight bearing, active or passive range of motion, or tenderness with Kellgren-Lawrence (KL grade of more than I were included. Patients with injury, inflammatory and metabolic diseases were excluded. Patients were put in a 10-hour fasting prior to withdrawal of morning blood samples for examinations of HA, CTX-I, interleukin 1 beta (IL-1β, and high sensitivity C reactive protein (hs-CRP level. Second void morning urine specimens were taken for CTXII assessment. HA, CTX-I and II levels were measured by enzyme-linked immunosorbent assay. RESULTS: Sixty menopausal female patients were included in this study, 35 with KL grade II, 17 grade III, and 8 grade IV. Means of CTX-II were significantly different between subjects KL grade IV and III (p=0.021. Correlation of KL grade was significant with CTX-II (p=0.001, r=0.412 and HA (p=0.0411, r=0.269. KL grades were not significantly associated with CTX-I (p=0.8364, r=-0.0272; IL-1β (p=0.5773, r=0.0853 and hs-CRP (p=0.2625, r=0.1470. CONCLUSIONS: CTX-II and HA were associated with severity of knee OA, suggesting that CTX-II and HA can be used as marker for knee OA severity. KEYWORDS: CTX-II, hyaluronic acid, otestoarthritis, knee.

  18. Ambulatory activity monitoring: Progress in measurement of activity, posture, and specific motion patterns in daily life

    J.B.J. Bussmann (Hans); U.W. Ebner-Priemer (Ulrich); J. Fahrenberg (Jochen)

    2009-01-01

    textabstractBehavior is central to psychology in almost any definition. Although observable activity is a core aspect of behavior, assessment strategies have tended to focus on emotional, cognitive, or physiological responses. When physical activity is assessed, it is done so mostly with questionnai

  19. Effects of comprehensive rehabilitation training in combination with multi-mode analgesia on body function recovery after tumor-type knee replacement

    Zhang, Junjuan; Wang, Yahan; Yang, Guangyu; Liu, Jing; Wang, Junjie

    2016-01-01

    Objective: To discuss the significance of comprehensive rehabilitation training combined with multimodal analgesia (MMA) for the early knee function recovery of patients with knee bone tumor who underwent prosthesis replacement operation. Methods: Sixty patients with knee bone tumor who underwent prosthesis replacement operation were selected and randomly divided into two groups according to rehabilitation training and postoperative analgesic methods, namely, observation group and control group, 30 cases in each group. The control group was treated with symptomatic treatment (drugs were given based on pain before and after surgery) and continuous passive motion (CPM) functional training, while the observation group was treated with comprehensive rehabilitation training combined with MMA. The compliance of patients in the two groups was compared and the first-time off-bed activity time was recorded. Recovery conditions of wounds were observed, and recovery conditions of limb functions after operations were evaluated. Results: The compliance of patients in the observation group was significantly higher than that in the control group, and the difference was statistically significant (Pknee (HSS) score and evaluation result of range of motion (ROM) of knees of the observation group were both better than those of the control group in different periods after operation, and the differences were statistically significant (Prehabilitation training combined with MMA can improve the compliance of patients and help patients off bed earlier, and remarkably promote the early recovery of knee functions; hence it deserves to be promoted clinically. PMID:27882029

  20. Asymmetric varus and valgus stability of the anatomic cadaver knee and the load sharing between collateral ligaments and bearing surfaces.

    Wang, Xiaonan; Malik, Aamer; Bartel, Donald L; Wickiewicz, Thomas L; Wright, Timothy

    2014-08-01

    Knee joint stability is important in maintaining normal joint motion during activities of daily living. Joint instability not only disrupts normal motion but also plays a crucial role in the initiation and progression of osteoarthritis. Our goal was to examine knee joint coronal plane stability under varus or valgus loading and to understand the relative contributions of the mechanisms that act to stabilize the knee in response to varus-valgus moments, namely, load distribution between the medial and lateral condyles and the ligaments. A robot testing system was used to determine joint stability in human cadaveric knees as described by the moment versus angular rotation behavior under varus and valgus loads at extension and at 30 deg and 90 deg of flexion. The anatomic knee joint was more stable in response to valgus than varus moments, and stability decreased with flexion angle. The primary mechanism for providing varus-valgus stability was the redistribution of the contact force on the articular surfaces from both condyles to a single condyle. Stretching of the collateral ligaments provided a secondary stabilizing mechanism after the lift-off of a condyle occurred. Compressive loads applied across the knee joint, such as would occur with the application of muscle forces, enhanced the ability of the articular surface to provide varus-valgus moment, and thus, helped stabilize the joint in the coronal plane. Coupled internal/external rotations and anteroposterior and medial-lateral translations were variable and in the case of the rotations were often as large as the varus-valgus rotations created by the applied moment.

  1. Vagal control of cardiac electrical activity and wall motion during ventricular fibrillation in large animals.

    Naggar, Isaac; Nakase, Ko; Lazar, Jason; Salciccioli, Louis; Selesnick, Ivan; Stewart, Mark

    2014-07-01

    Vagal inputs control pacemaking and conduction systems in the heart. Anatomical evidence suggests a direct ventricular action, but functional evidence that separates direct and indirect (via the conduction system) vagal actions is less well established. We studied vagus nerve stimulation (VNS) during sinus rhythm and ventricular fibrillation (VF) in pigs and sheep to determine: 1) the range of unilateral and bilateral actions (inotropic and chronotropic) and 2) whether VNS alters left ventricular motion and/or electrical activity during VF, a model of abnormal electrical conduction of the left ventricle that excludes sinus and atrioventricular nodal function. Adult pigs (N=8) and sheep (N=10) were anesthetized with urethane and mechanically ventilated. VNS was performed in animals at 1, 2, 5, 10, 20, 50, and 100Hz for 20s. VF was induced with direct current to the ventricles or occlusion of the left anterior descending coronary artery. In 4 pigs and 3 sheep, left ventricular wall motion was assessed from endocardial excursion in epicardial echocardiography. In sheep and pigs, the best frequency among those tested for VNS during sinus rhythm to produce sustained electrical and mechanical ventricular standstill was 50Hz for unilateral or bilateral stimulation. When applied during VF, bilateral VNS increased the variability of the dominant VF frequency, indicating a direct impact on the excitability of ventricular myocytes, and decreased endocardial excursion by more than 50% during VF. We conclude that the vagus nerve directly modulates left ventricular function independently from its effects on the conduction system.

  2. Motion verb sentences activate left posterior middle temporal cortex despite static context

    Wallentin, M; Ellegaard Lund, Torben; Østergaard, Svend;

    2005-01-01

    The left posterior middle temporal region, anterior to V5/MT, has been shown to be responsive both to images with implied motion, to simulated motion, and to motion verbs. In this study, we investigated whether sentence context alters the response of the left posterior middle temporal region. 'Fi...

  3. Control of a Virtual Vehicle Influences Postural Activity and Motion Sickness

    Dong, Xiao; Yoshida, Ken; Stoffregen, Thomas A.

    2011-01-01

    Everyday experience suggests that drivers are less susceptible to motion sickness than passengers. In the context of inertial motion (i.e., physical displacement), this effect has been confirmed in laboratory research using whole body motion devices. We asked whether a similar effect would occur in the context of simulated vehicles in a visual…

  4. Evaluation of total knee mechanics using a crouching simulator with a synthetic knee substitute.

    Lowry, Michael; Rosenbaum, Heather; Walker, Peter S

    2016-05-01

    Mechanical evaluation of total knees is frequently required for aspects such as wear, strength, kinematics, contact areas, and force transmission. In order to carry out such tests, we developed a crouching simulator, based on the Oxford-type machine, with novel features including a synthetic knee including ligaments. The instrumentation and data processing methods enabled the determination of contact area locations and interface forces and moments, for a full flexion-extension cycle. To demonstrate the use of the simulator, we carried out a comparison of two different total knee designs, cruciate retaining and substituting. The first part of the study describes the simulator design and the methodology for testing the knees without requiring cadaveric knee specimens. The degrees of freedom of the anatomic hip and ankle joints were reproduced. Flexion-extension was obtained by changing quadriceps length, while variable hamstring forces were applied using springs. The knee joint was represented by three-dimensional printed blocks on to which the total knee components were fixed. Pretensioned elastomeric bands of realistic stiffnesses passed through holes in the block at anatomical locations to represent ligaments. Motion capture of the knees during flexion, together with laser scanning and computer modeling, was used to reconstruct contact areas on the bearing surfaces. A method was also developed for measuring tibial component interface forces and moments as a comparative assessment of fixation. The method involved interposing Tekscan pads at locations on the interface. Overall, the crouching machine and the methodology could be used for many different mechanical measurements of total knee designs, adapted especially for comparative or parametric studies.

  5. Trunk biomechanics and its association with hip and knee kinematics in patients with and without patellofemoral pain.

    Nakagawa, Theresa Helissa; Maciel, Carlos Dias; Serrão, Fábio Viadanna

    2015-02-01

    Patellofemoral pain (PFP) is a common lower extremity condition observed in sports clinics. Recently, it has been suggested that trunk motion could affect hip and knee biomechanics in the frontal plane. Thus, the purpose of the study was compare trunk kinematics, strength and muscle activation between people with PFP and healthy participants. In addition, the associations among trunk biomechanics, hip and knee kinematics were analysed. Thirty people with PFP and thirty pain-free individuals participated. The peak ipsilateral trunk lean, hip adduction, and knee abduction were evaluated with an electromagnetic tracking system, and the surface electromyographic signals of the iliocostalis and external oblique muscle were recorded during single-leg squats. Trunk extension and trunk flexion with rotation isometric strength and side bridge tests were quantified using a handheld dynamometer. Compared with the control group, the PFP group demonstrated increased ipsilateral trunk lean, hip adduction and knee abduction (p = 0.02-0.04) during single-leg squat accompanied with decreased trunk isometric strength (p = biomechanics were found in people with PFP. No relationship among trunk, hip and knee biomechanics was found in the PFP group, suggesting that people with PFP show different movement patterns compared to the control group.

  6. Efficacy of multimodal cocktail periarticular injection with or without steroid in total knee arthroplasty

    YUE De-bo; WANG Bai-liang; LIU Kun-peng; GUO Wan-shou

    2013-01-01

    Background Multimodal cocktail periarticular injection (MCPI) with a large volume of low concentration local anesthetics,adrenaline,and anti-inflammatory agents such as non-steroidal anti-inflammatory drug or steroids have shown good pain control and improvement in range of motion after surgery.This study compares the efficacy of pain control after total knee arthroplasty,using multimodal cocktail periarticular injection with steroid or without steroid.Methods This is a prospective,double-blinded,randomized and control study.Seventy-two patients with osteoarthritis that met clinical criteria for total knee arthroplasty were recruited into the study,and were randomized to receive either multimodal cocktail periarticular injection with steroid or without steroid.Pain was assessed by visual analogue scale (VAS) at preoperative and postoperative at rest,and during activity.The range of motion was recorded preoperatively and postoperatively.The amount of daily and cumulative morphine consumption were measured by patient-controlled analgesia in the first 72 hours postoperatively.The duration of celecoxib usage was also recorded at the last follow-up.Results There were no differences between the non-steroid and steroid groups with regard to VAS at rest and during activity,or range of motion,at any postoperative observation time.The postoperative Knee Society Knee Score in the steroid group improved significantly as compared with that in non-steroid group at the one-month (84.1±13.1 and 65.9±12.1; P <0.0045),three-month follow-up (90.2±16.3 and 72.5±16.6; P <0.0027),but after postoperative six-month the Knee Society Knee Score showed no significant difference between the groups.There was no significant difference in consumption of the morphine about daily or total consumption within 72 hours between the two groups.The duration of celecoxib usage in patients in the steroid group was significantly shorter than that in the non-steroid group ((7.2±0.7) compared with

  7. A prospective study on knee proprioception after meniscal allograft transplantation.

    Thijs, Y; Witvrouw, E; Evens, B; Coorevits, P; Almqvist, F; Verdonk, R

    2007-06-01

    The meniscus plays an important role in the proprioceptive ability of the knee joint. The aim of this prospective study was to assess the short-term influence of a meniscus replacement on the proprioception of the knee. Fourteen patients who had undergone a fresh meniscal allograft transplantation between May 2001 and June 2003 were tested pre-operatively and 6 months post-operatively. Disability regarding pain, stiffness and functionality of the affected knee during daily activities was measured by the Western Ontario and McMaster Universities Arthritis (WOMAC) scale. The knee joint position sense was assessed using the Biodex System 3 isokinetic dynamometer. The results of the WOMAC scale showed no significant differences concerning pain, stiffness or knee function between the pre- and post-operative condition of the knee. Assessment of the knee joint position sense at a reference point of 70 degrees of knee flexion revealed a significant improvement of the proprioception of the operated knee at 6 months after surgery compared with the pre-operative condition. The results of this study suggest that although no significant improvement of pain and functionality of the operated knee occurred at this short-term follow-up period, a meniscal allograft transplantation seems to have a significant positive effect on the joint position sense of the previously meniscectomised knee.

  8. Dopamine Activation Preserves Visual Motion Perception Despite Noise Interference of Human V5/MT

    Yousif, Nada; Fu, Richard Z.; Abou-El-Ela Bourquin, Bilal; Bhrugubanda, Vamsee; Schultz, Simon R.

    2016-01-01

    When processing sensory signals, the brain must account for noise, both noise in the stimulus and that arising from within its own neuronal circuitry. Dopamine receptor activation is known to enhance both visual cortical signal-to-noise-ratio (SNR) and visual perceptual performance; however, it is unknown whether these two dopamine-mediated phenomena are linked. To assess this, we used single-pulse transcranial magnetic stimulation (TMS) applied to visual cortical area V5/MT to reduce the SNR focally and thus disrupt visual motion discrimination performance to visual targets located in the same retinotopic space. The hypothesis that dopamine receptor activation enhances perceptual performance by improving cortical SNR predicts that dopamine activation should antagonize TMS disruption of visual perception. We assessed this hypothesis via a double-blinded, placebo-controlled study with the dopamine receptor agonists cabergoline (a D2 agonist) and pergolide (a D1/D2 agonist) administered in separate sessions (separated by 2 weeks) in 12 healthy volunteers in a William's balance-order design. TMS degraded visual motion perception when the evoked phosphene and the visual stimulus overlapped in time and space in the placebo and cabergoline conditions, but not in the pergolide condition. This suggests that dopamine D1 or combined D1 and D2 receptor activation enhances cortical SNR to boost perceptual performance. That local visual cortical excitability was unchanged across drug conditions suggests the involvement of long-range intracortical interactions in this D1 effect. Because increased internal noise (and thus lower SNR) can impair visual perceptual learning, improving visual cortical SNR via D1/D2 agonist therapy may be useful in boosting rehabilitation programs involving visual perceptual training. SIGNIFICANCE STATEMENT In this study, we address the issue of whether dopamine activation improves visual perception despite increasing sensory noise in the visual cortex

  9. Anteroposterior glide versus rotating platform low contact stress (LCS knee arthroplasty: a randomised controlled trial

    Wynn-Jones Charles

    2007-08-01

    Full Text Available Abstract Background Fifty thousand knee replacements are performed annually in the UK at an estimated cost of £150 million. Post-operative improvement depends on a number of factors including implant design and patient associated factors. To our knowledge there are no published study's comparing the results of AP glide and rotating platform designs of LCS knee arthroplasty. Therefore we feel that a study is required to investigate and compare the effects of two types of LCS total knee arthroplasty on joint proprioception and range of motion. Methods/Design Patients will be randomised to receive either a LCS AP glide or Rotating platform prosthesis. Clinical scores (Oxford knee score, American knee society score, EuroQol, range of motion and proprioception will be assessed prior to and at 3,6, 12 and 24 months after the operation. Proprioception will be assessed in terms of absolute error angle (mean difference between the target angle and the response angle. Knee angles will be measured in degrees using an electromagnetic tracking device, Polhemus 3Space Fastrak that detects positions of sensors placed on the test limb. Student's t-test will be used to compare the mean of two groups. Discussion Evidence is lacking concerning the best prosthesis to use for patients undergoing total knee replacement. This pragmatic randomised trial will test the null hypothesis that anteroposterior glide LCS knee arthroplasty does not result in better post operative knee motion and proprioception as compared to rotating platform LCS knee. Trial Registration ISRCTN52943804

  10. Driving technology for improving motion quality of active-matrix organic light-emitting diode display

    Kim, Jongbin; Kim, Minkoo; Kim, Jong-Man; Kim, Seung-Ryeol; Lee, Seung-Woo

    2014-09-01

    This paper reports transient response characteristics of active-matrix organic light emitting diode (AMOLED) displays for mobile applications. This work reports that the rising responses look like saw-tooth waveform and are not always faster than those of liquid crystal displays. Thus, a driving technology is proposed to improve the rising transient responses of AMOLED based on the overdrive (OD) technology. We modified the OD technology by combining it with a dithering method because the conventional OD method cannot successfully enhance all the rising responses. Our method can improve all the transitions of AMOLED without modifying the conventional gamma architecture of drivers. A new artifact is found when OD is applied to certain transitions. We propose an optimum OD selection method to mitigate the artifact. The implementation results show the proposed technology can successfully improve motion quality of scrolling texts as well as moving pictures in AMOLED displays.

  11. Aftershock activity of the 2015 Gorkha, Nepal, earthquake determined using the Kathmandu strong motion seismographic array

    Ichiyanagi, Masayoshi; Takai, Nobuo; Shigefuji, Michiko; Bijukchhen, Subeg; Sasatani, Tsutomu; Rajaure, Sudhir; Dhital, Megh Raj; Takahashi, Hiroaki

    2016-02-01

    The characteristics of aftershock activity of the 2015 Gorkha, Nepal, earthquake (Mw 7.8) were evaluated. The mainshock and aftershocks were recorded continuously by the international Kathmandu strong motion seismographic array operated by Hokkaido University and Tribhuvan University. Full waveform data without saturation for all events enabled us to clarify aftershock locations and decay characteristics. The aftershock distribution was determined using the estimated local velocity structure. The hypocenter distribution in the Kathmandu metropolitan region was well determined and indicated earthquakes located shallower than 12 km depth, suggesting that aftershocks occurred at depths shallower than the Himalayan main thrust fault. Although numerical investigation suggested less resolution for the depth component, the regional aftershock epicentral distribution of the entire focal region clearly indicated earthquakes concentrated in the eastern margin of the major slip region of the mainshock. The calculated modified Omori law's p value of 1.35 suggests rapid aftershock decay and a possible high temperature structure in the aftershock region.

  12. Recommended survey designs for occupancy modelling using motion-activated cameras: insights from empirical wildlife data.

    Shannon, Graeme; Lewis, Jesse S; Gerber, Brian D

    2014-01-01

    Motion-activated cameras are a versatile tool that wildlife biologists can use for sampling wild animal populations to estimate species occurrence. Occupancy modelling provides a flexible framework for the analysis of these data; explicitly recognizing that given a species occupies an area the probability of detecting it is often less than one. Despite the number of studies using camera data in an occupancy framework, there is only limited guidance from the scientific literature about survey design trade-offs when using motion-activated cameras. A fuller understanding of these trade-offs will allow researchers to maximise available resources and determine whether the objectives of a monitoring program or research study are achievable. We use an empirical dataset collected from 40 cameras deployed across 160 km(2) of the Western Slope of Colorado, USA to explore how survey effort (number of cameras deployed and the length of sampling period) affects the accuracy and precision (i.e., error) of the occupancy estimate for ten mammal and three virtual species. We do this using a simulation approach where species occupancy and detection parameters were informed by empirical data from motion-activated cameras. A total of 54 survey designs were considered by varying combinations of sites (10-120 cameras) and occasions (20-120 survey days). Our findings demonstrate that increasing total sampling effort generally decreases error associated with the occupancy estimate, but changing the number of sites or sampling duration can have very different results, depending on whether a species is spatially common or rare (occupancy = ψ) and easy or hard to detect when available (detection probability = p). For rare species with a low probability of detection (i.e., raccoon and spotted skunk) the required survey effort includes maximizing the number of sites and the number of survey days, often to a level that may be logistically unrealistic for many studies. For common species with

  13. A Circular Motion Activity with Hot Wheels® Rev-Ups

    Wagner, Glenn

    2009-02-01

    Hot Wheels® Rev-Ups provide a pedagogically engaging and inexpensive culminating activity for the application of circular motion with constant speed in introductory mechanics. The introductory Rev-Up, shown in Fig. 1, consists of a very durable car with two strong magnets built into the front and back of the car. The track is a piece of flexible plastic with a built-in metallic strip through its center that can then be formed into a circle. Pushing the car forward several times on a flat surface allows the car to move in a vertical circle when placed inside the track. What makes this toy attractive is that the gearing system allows the car to move at a relatively constant speed for about three to five seconds before slowing down appreciably.

  14. Active Head Motion Compensation of TMS Robotic System Using Neuro-Fuzzy Estimation

    Wan Zakaria W.N.

    2016-01-01

    Full Text Available Transcranial Magnetic Stimulation (TMS allows neuroscientist to study human brain behaviour and also become an important technique for changing the activity of brain neurons and the functions they sub serve. However, conventional manual procedure and robotized TMS are currently unable to precisely position the TMS coil because of unconstrained subject’s head movement and excessive contact force between the coil and subject’s head. This paper addressed this challenge by proposing an adaptive neuro-fuzzy force control to enable low contact force with a moving target surface. A learning and adaption mechanism is included in the control scheme to improve position disturbance estimation. The results show the ability of the proposed force control scheme to compensate subject’s head motions while maintaining desired contact force, thus allowing for more accurate and repeatable TMS procedures.

  15. Motion or activity: their role in intra- and inter-subject variation in fMRI

    Lund, Torben E; Nørgaard, Minna D; Rostrup, Egill;

    2005-01-01

    MRI to pre-surgical planning because of a higher requirement for intra-subject precision. The purpose of this study was to investigate the impact of residual movement artefacts on intra-subject and inter-subject variability in the observed fMRI activation. Ten subjects were examined using three different...... word-generation tasks. Two of the subjects were examined 10 times on 10 different days using the same paradigms. We systematically investigated one approach of correcting for residual movement effects: the inclusion of regressors describing movement-related effects in the design matrix of a General...... Linear Model (GLM). The data were analysed with and without modeling the residual movement artefacts and the impact on inter-session variance was assessed using F-contrasts. Inclusion of motion parameters in the analysis significantly reduced both the intra-subject as well as the inter-subject-variance...

  16. Measurements of Generated Energy/Electrical Quantities from Locomotion Activities Using Piezoelectric Wearable Sensors for Body Motion Energy Harvesting.

    Proto, Antonino; Penhaker, Marek; Bibbo, Daniele; Vala, David; Conforto, Silvia; Schmid, Maurizio

    2016-04-12

    In this paper, two different piezoelectric transducers-a ceramic piezoelectric, lead zirconate titanate (PZT), and a polymeric piezoelectric, polyvinylidene fluoride (PVDF)-were compared in terms of energy that could be harvested during locomotion activities. The transducers were placed into a tight suit in proximity of the main body joints. Initial testing was performed by placing the transducers on the neck, shoulder, elbow, wrist, hip, knee and ankle; then, five locomotion activities-walking, walking up and down stairs, jogging and running-were chosen for the tests. The values of the power output measured during the five activities were in the range 6 µW-74 µW using both transducers for each joint.

  17. Interpolation function for approximating knee joint behavior in human gait

    Toth-Taşcǎu, Mirela; Pater, Flavius; Stoia, Dan Ioan

    2013-10-01

    Starting from the importance of analyzing the kinematic data of the lower limb in gait movement, especially the angular variation of the knee joint, the paper propose an approximation function that can be used for processing the correlation among a multitude of knee cycles. The approximation of the raw knee data was done by Lagrange polynomial interpolation on a signal acquired using Zebris Gait Analysis System. The signal used in approximation belongs to a typical subject extracted from a lot of ten investigated subjects, but the function domain of definition belongs to the entire group. The study of the knee joint kinematics plays an important role in understanding the kinematics of the gait, this articulation having the largest range of motion in whole joints, in gait. The study does not propose to find an approximation function for the adduction-abduction movement of the knee, this being considered a residual movement comparing to the flexion-extension.

  18. Dynamic analysis of astronaut motions in microgravity: Applications for Extravehicular Activity (EVA)

    Newman, Dava J.

    1995-01-01

    Simulations of astronaut motions during extravehicular activity (EVA) tasks were performed using computational multibody dynamics methods. The application of computational dynamic simulation to EVA was prompted by the realization that physical microgravity simulators have inherent limitations: viscosity in neutral buoyancy tanks; friction in air bearing floors; short duration for parabolic aircraft; and inertia and friction in suspension mechanisms. These limitations can mask critical dynamic effects that later cause problems during actual EVA's performed in space. Methods of formulating dynamic equations of motion for multibody systems are discussed with emphasis on Kane's method, which forms the basis of the simulations presented herein. Formulation of the equations of motion for a two degree of freedom arm is presented as an explicit example. The four basic steps in creating the computational simulations were: system description, in which the geometry, mass properties, and interconnection of system bodies are input to the computer; equation formulation based on the system description; inverse kinematics, in which the angles, velocities, and accelerations of joints are calculated for prescribed motion of the endpoint (hand) of the arm; and inverse dynamics, in which joint torques are calculated for a prescribed motion. A graphical animation and data plotting program, EVADS (EVA Dynamics Simulation), was developed and used to analyze the results of the simulations that were performed on a Silicon Graphics Indigo2 computer. EVA tasks involving manipulation of the Spartan 204 free flying astronomy payload, as performed during Space Shuttle mission STS-63 (February 1995), served as the subject for two dynamic simulations. An EVA crewmember was modeled as a seven segment system with an eighth segment representing the massive payload attached to the hand. For both simulations, the initial configuration of the lower body (trunk, upper leg, and lower leg) was a neutral

  19. Comparison of electromyographic activity and range of neck motion in violin students with and without neck pain during playing.

    Park, Kyue-nam; Kwon, Oh-yun; Ha, Sung-min; Kim, Su-jung; Choi, Hyun-jung; Weon, Jong-hyuck

    2012-12-01

    Neck pain is common in violin students during a musical performance. The purpose of this study was to compare electromyographic (EMG) activity in superficial neck muscles with neck motion when playing the violin as well as neck range of motion (ROM) at rest, between violin students with and without neck pain. Nine violin students with neck pain and nine age- and gender-matched subjects without neck pain were recruited. Muscle activity of the bilateral upper trapezius, sternocleidomastoid, and superficial cervical extensor muscles was measured using surface EMG. Kinematic data on neck motion while playing and active neck ROM were also measured using a three-dimensional motion analysis system. Independent t-tests were used to compare EMG activity with kinematic data between groups. These analyses revealed that while playing, both the angle of left lateral bending and leftward rotation of the cervical spine were significantly greater in the neck pain group than among those without neck pain. Similarly, EMG activity of the left upper trapezius, both cervical extensors, and both sternocleidomastoid muscles were significantly greater in the neck pain group. The active ROM of left axial rotation was significantly lower in the neck pain group. These results suggest that an asymmetric playing posture and the associated increased muscle activity as well as decreased neck axial rotation may contribute to neck pain in violin students.

  20. Effectiveness enhancement of a cycloidal wind turbine by individual active control of blade motion

    Hwang, In Seong; Lee, Yun Han; Kim, Seung Jo

    2007-04-01

    In this paper, a research for the effectiveness enhancement of a Cycloidal Wind Turbine by individual active control of blade motion is described. To improve the performance of the power generation system, which consists of several straight blades rotating about axis in parallel direction, the cycloidal blade system and the individual active blade control method are adopted. It has advantages comparing with horizontal axis wind turbine or conventional vertical axis wind turbine because it maintains optimal blade pitch angles according to wind speed, wind direction and rotor rotating speed to produce high electric power at any conditions. It can do self-starting and shows good efficiency at low wind speed and complex wind condition. Optimal blade pitch angle paths are obtained through CFD analysis according to rotor rotating speed and wind speed. The individual rotor blade control system consists of sensors, actuators and microcontroller. To realize the actuating device, servo motors are installed to each rotor blade. Actuating speed and actuating force are calculated to compare with the capacities of servo motor, and some delays of blade pitch angles are corrected experimentally. Performance experiment is carried out by the wind blowing equipment and Labview system, and the rotor rotates from 50 to 100 rpm according to the electric load. From this research, it is concluded that developing new vertical axis wind turbine, Cycloidal Wind Turbine which is adopting individual active blade pitch control method can be a good model for small wind turbine in urban environment.

  1. Regeneration of Cartilage in Human Knee Osteoarthritis with Autologous Adipose Tissue-Derived Stem Cells and Autologous Extracellular Matrix

    Jaewoo Pak

    2016-08-01

    Full Text Available This clinical case series demonstrates that percutaneous injections of autologous adipose tissue-derived stem cells (ADSCs and homogenized extracellular matrix (ECM in the form of adipose stromal vascular fraction (SVF, along with hyaluronic acid (HA and platelet-rich plasma (PRP activated by calcium chloride, could regenerate cartilage-like tissue in human knee osteoarthritis (OA patients. Autologous lipoaspirates were obtained from adipose tissue of the abdominal origin. Afterward, the lipoaspirates were minced to homogenize the ECM. These homogenized lipoaspirates were then mixed with collagenase and incubated. The resulting mixture of ADSCs and ECM in the form of SVF was injected, along with HA and PRP activated by calcium chloride, into knees of three Korean patients with OA. The same affected knees were reinjected weekly with additional PRP activated by calcium chloride for 3 weeks. Pretreatment and post-treatment magnetic resonance imaging (MRI data, functional rating index, range of motion (ROM, and pain score data were then analyzed. All patients' MRI data showed cartilage-like tissue regeneration. Along with MRI evidence, the measured physical therapy outcomes in terms of ROM, subjective pain, and functional status were all improved. This study demonstrates that percutaneous injection of ADSCs with ECM contained in autologous adipose SVF, in conjunction with HA and PRP activated by calcium chloride, is a safe and potentially effective minimally invasive therapy for OA of human knees.

  2. Ligament balancing in total knee arthroplasty—Medial stabilizing technique

    Shuichi Matsuda

    2015-10-01

    Full Text Available Ligament balancing is one of the most important surgical techniques for successful total knee arthroplasty. It has traditionally been recommended that medial and lateral as well as flexion and extension gaps are equal. This article reviews the relevant literature and discusses the clinical importance of the aforementioned gaps. Current evidence indicates that achieving medial stability throughout the range of motion should be a high priority in ligament balancing in total knee arthroplasty. Finally, the medial stabilising surgical technique, which aims to achieve good medial stability in posterior cruciate-retaining total knee arthroplasty, is introduced.

  3. Cooling Does Not Affect Knee Proprioception

    Ozmun, John C.; Thieme, Heather A.; Ingersoll, Christopher D; Knight, Kenneth L

    1996-01-01

    The effect of cooling on proprioception of the knee has not been studied extensively. In this study, we investigated the movement reproduction (timing and accuracy) aspect of proprioception. Subjects were tested under two conditions: a 20-minute application of ice and control. Proprioceptive accuracy and timing were measured by passively moving the knee, then comparing the subject's active reproduction of the passive movement. Subjects were blindfolded, then tested in three sectors of the kne...

  4. Predicting dynamic knee joint load with clinical measures in people with medial knee osteoarthritis.

    Hunt, Michael A; Bennell, Kim L

    2011-08-01

    Knee joint loading, as measured by the knee adduction moment (KAM), has been implicated in the pathogenesis of knee osteoarthritis (OA). Given that the KAM can only currently be accurately measured in the laboratory setting with sophisticated and expensive equipment, its utility in the clinical setting is limited. This study aimed to determine the ability of a combination of four clinical measures to predict KAM values. Three-dimensional motion analysis was used to calculate the peak KAM at a self-selected walking speed in 47 consecutive individuals with medial compartment knee OA and varus malalignment. Clinical predictors included: body mass; tibial angle measured using an inclinometer; walking speed; and visually observed trunk lean toward the affected limb during the stance phase of walking. Multiple linear regression was performed to predict KAM magnitudes using the four clinical measures. A regression model including body mass (41% explained variance), tibial angle (17% explained variance), and walking speed (9% explained variance) explained a total of 67% of variance in the peak KAM. Our study demonstrates that a set of measures easily obtained in the clinical setting (body mass, tibial alignment, and walking speed) can help predict the KAM in people with medial knee OA. Identifying those patients who are more likely to experience high medial knee loads could assist clinicians in deciding whether load-modifying interventions may be appropriate for patients, whilst repeated assessment of joint load could provide a mechanism to monitor disease progression or success of treatment.

  5. Measurements of Generated Energy/Electrical Quantities from Locomotion Activities Using Piezoelectric Wearable Sensors for Body Motion Energy Harvesting

    Antonino Proto

    2016-04-01

    Full Text Available In this paper, two different piezoelectric transducers—a ceramic piezoelectric, lead zirconate titanate (PZT, and a polymeric piezoelectric, polyvinylidene fluoride (PVDF—were compared in terms of energy that could be harvested during locomotion activities. The transducers were placed into a tight suit in proximity of the main body joints. Initial testing was performed by placing the transducers on the neck, shoulder, elbow, wrist, hip, knee and ankle; then, five locomotion activities—walking, walking up and down stairs, jogging and running—were chosen for the tests. The values of the power output measured during the five activities were in the range 6 µW–74 µW using both transducers for each joint.

  6. Imaging of knee arthroplasty

    Miller, Theodore T. [Department of Radiology, North Shore University Hospital, 825 Northern Blvd., Great Neck, NY 11021 (United States)]. E-mail: TMiller@NSHS.edu

    2005-05-01

    Knee replacement surgery, either with unicompartmental or total systems, is common. The purpose of this manuscript is to review the appearance of normal knee arthroplasty and the appearances of complications such as infection, polyethylene wear, aseptic loosening and particle-induced osteolysis, patellofemoral abnormalities, axial instability, and periprosthetic and component fracture. Knowledge of the potential complications and their imaging appearances will help the radiologist in the diagnostic evaluation of the patient with a painful knee arthroplasty.

  7. A parallelogram-based compliant remote-center-of-motion stage for active parallel alignment

    Qu, Jianliang; Chen, Weihai; Zhang, Jianbin

    2014-09-01

    Parallel alignment stage with remote-center-of-motion (RCM) is of key importance in precision out-of-plane aligning since it can eliminate the harmful lateral displacement generated at the output platform. This paper presents the development of a parallelogram-based compliant RCM stage for active parallel alignment. Different from conventional parallelogram-based RCM mechanism, the proposed stage is designed with compliant mechanisms, which endows the stage with many attractive merits when used in precision micro-/nanomanipulations. A symmetric double-parallelogram mechanism (SDPM) based on flexure hinges is developed as the rotary guiding component to realize desired RCM function. Due to the geometrical constraint of the SDPM, the operating space of the stage can be easily adjusted by bending the input links without loss of rotational precision. The stage is driven by a piezoelectric actuator and its output motion is measured by non-contact displacement sensors. Based on pseudo-rigid-body simplification method, the analytical models predicting kinematics, statics, and dynamics of the RCM stage have been established. Besides, the dimensional optimization is conducted in order to maximize the first resonance frequency of the stage. After that, finite element analysis is conducted to validate the established models and the prototype of the stage is fabricated for performance tests. The experimental results show that the developed RCM stage has a rotational range of 1.45 mrad while the maximum center shift of the RCM point is as low as 1 μm, which validate the effectiveness of the proposed scheme.

  8. Knee loading patterns in a simulated netball landing task.

    Stuelcken, Max; Greene, Andrew; Smith, Richard; Vanwanseele, Benedicte

    2013-01-01

    The knee is a common site of injury in netball players. In this study, 10 high-performance netball players underwent a biomechanical assessment of their single leg landing technique whilst receiving a pass. Three-dimensional video and ground reaction force data were recorded using a motion analysis system. Net internal knee joint moments were calculated using a rigid body analysis and inverse dynamics. The kinematics of the support leg and front-on video footage was used to investigate whether players adhered to guidelines on safe and effective landing strategies. Results indicated that for most players the internal valgus moment was the largest frontal plane knee moment during the landing phase. This may reflect a relatively greater need to resist varus knee excursion or may be related to the kinematics of the hip. For 6 of the 10 players the rapid change to an internal knee valgus moment coincided with hip adduction. Since an increase in the magnitude of the internal valgus moment may increase the compressive forces in the medial compartment of the knee, further work should be undertaken to determine if a neuromuscular training intervention to improve the strength of the hip musculature may be beneficial for these players. A large relative excursion of the knee compared to the hip may indicate that these players had a greater reliance on the more distal segments of the lower extremity for the attenuation of the ground reaction forces. This information may be used to better understand potential knee injury mechanisms in netball players.

  9. Breathing pattern, thoracoabdominal motion and muscular activity during three breathing exercises

    G.M. Tomich

    2007-10-01

    Full Text Available The objective of the present study was to evaluate breathing pattern, thoracoabdominal motion and muscular activity during three breathing exercises: diaphragmatic breathing (DB, flow-oriented (Triflo II incentive spirometry and volume-oriented (Voldyne incentive spirometry. Seventeen healthy subjects (12 females, 5 males aged 23 ± 5 years (mean ± SD were studied. Calibrated respiratory inductive plethysmography was used to measure the following variables during rest (baseline and breathing exercises: tidal volume (Vt, respiratory frequency (f, rib cage contribution to Vt (RC/Vt, inspiratory duty cycle (Ti/Ttot, and phase angle (PhAng. Sternocleidomastoid muscle activity was assessed by surface electromyography. Statistical analysis was performed by ANOVA and Tukey or Friedman and Wilcoxon tests, with the level of significance set at P < 0.05. Comparisons between baseline and breathing exercise periods showed a significant increase of Vt and PhAng during all exercises, a significant decrease of f during DB and Voldyne, a significant increase of Ti/Ttot during Voldyne, and no significant difference in RC/Vt. Comparisons among exercises revealed higher f and sternocleidomastoid activity during Triflo II (P < 0.05 with respect to DB and Voldyne, without a significant difference in Vt, Ti/Ttot, PhAng, or RC/Vt. Exercises changed the breathing pattern and increased PhAng, a variable of thoracoabdominal asynchrony, compared to baseline. The only difference between DB and Voldyne was a significant increase of Ti/Ttot compared to baseline. Triflo II was associated with higher f values and electromyographic activity of the sternocleidomastoid. In conclusion, DB and Voldyne showed similar results while Triflo II showed disadvantages compared to the other breathing exercises.

  10. Detection of active sacroiliitis with ankylosing spondylitis through intravoxel incoherent motion diffusion-weighted MR imaging

    Zhao, Ying-hua [Third Affiliated Hospital of Southern Medical University, Academy of Orthopedics, Department of Radiology, Guangzhou (China); Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, Guangzhou (China); Li, Shao-lin; Zhao, Xiang-cheng; Hu, Shao-yong; Liu, Zhen-hua [Third Affiliated Hospital of Southern Medical University, Academy of Orthopedics, Department of Radiology, Guangzhou (China); Liu, Zai-yi; Chen, Xin; Liang, Chang-hong [Guangdong Academy of Medical Sciences, Department of Radiology, Guangdong General Hospital, Guangzhou (China); Mei Ms, Ying-jie [Philips Healthcare, Guangzhou (China); Chan, Queenie [Philips Electronics Hong Kong Ltd, Hong Kong (China)

    2015-09-15

    To confirm feasibility and assess intravoxel incoherent motion (IVIM) to differentiate active sacroiliitis and ankylosing spondylitis. Forty-one patients were divided into two groups, an active group (n = 20) and a chronic group (n = 21), according to the Bath Ankylosing Spondylitis (AS) Disease Activity Index (BASDAI) and laboratory parameters. In addition, 21 healthy volunteers were chosen as the control group. Tissue diffusivity (D{sub slow}), perfusion fraction (f), and pseudo-diffusion coefficient (D{sub fast}) values were obtained for all three groups. One-way analysis of variance and receiver operating characteristic analysis were performed for all parameters. There was good interobserver agreement on the measurements between the two observers. The optimal cut-off values (with respective AUC, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio) between active and chronic groups were D{sub slow} = 0.53 x 10{sup -3} mm{sup 2}/s (0.976, 90 %, 95.2 %, 18.9, 0.10) and f = 0.09 (0.545, 20 %, 95.5 %, 4.2, 0.84), and between chronic and control groups were D{sub slow} = 0.22 x 10{sup -3} mm{sup 2}/s (0.517, 9.52 %, 100 %, no number, 0.9) and f = 0.09 (0.935, 95.24 %, 80.95 %, 5, 0.059). D{sub slow} and f of IVIM diffusion-weighted (DW)-MRI in AS show a significant difference in the values of diffusion of water molecules and fractional perfusion-related volume among the three groups. (orig.)

  11. Effects of Aquatic Therapy and Land-Based Therapy versus Land-Based Therapy Alone on Range of Motion, Edema, and Function after Hip or Knee Replacement: A Systematic Review and Meta-analysis

    Gibson, Alison J.; Shields, Nora

    2015-01-01

    Purpose: To determine whether aquatic therapy in combination with land-based therapy improves patient outcomes after hip or knee arthroplasty compared with land-based therapy alone. Methods: For this systematic review, six online databases (MEDLINE, CINAHL, AMED, EMBASE, Cochrane, and PEDro) were searched from the earliest date available until September 2013. Controlled trials published in English in a peer-reviewed journal that compared aquatic therapy in combination with land-based therapy ...

  12. Platelet Rich Plasma and Knee Surgery

    Mikel Sánchez

    2014-01-01

    Full Text Available In orthopaedic surgery and sports medicine, the knee joint has traditionally been considered the workhorse. The reconstruction of every damaged element in this joint is crucial in achieving the surgeon’s goal to restore the knee function and prevent degeneration towards osteoarthritis. In the last fifteen years, the field of regenerative medicine is witnessing a boost of autologous blood-derived platelet rich plasma products (PRPs application to effectively mimic and accelerate the tissue healing process. The scientific rationale behind PRPs is the delivery of growth factors, cytokines, and adhesive proteins present in platelets and plasma, as well as other biologically active proteins conveyed by the plasma such as fibrinogen, prothrombin, and fibronectin; with this biological engineering approach, new perspectives in knee surgery were opened. This work describes the use of PRP to construct and repair every single anatomical structure involved in knee surgery, detailing the process conducted in ligament, meniscal, and chondral surgery.

  13. A new method to measure post-traumatic joint contractures in the rabbit knee.

    Hildebrand, Kevin A; Holmberg, Michael; Shrive, Nigel

    2003-12-01

    A new device and method to measure rabbit knee joint angles are described. The method was used to measure rabbit knee joint angles in normal specimens and in knee joints with obvious contractures. The custom-designed and manufactured gripping device has two clamps. The femoral clamp sits on a pinion gear that is driven by a rack attached to a materials testing system. A 100 N load cell in series with the rack gives force feedback. The tibial clamp is attached to a rotatory potentiometer. The system allows the knee joint multiple degrees-of-freedom (DOF). There are two independent DOF (compression-distraction and internal-external rotation) and two coupled motions (medial-lateral translation coupled with varus-valgus rotation; anterior-posterior translation coupled with flexion-extension rotation). Knee joint extension-flexion motion is measured, which is a combination of the materials testing system displacement (converted to degrees of motion) and the potentiometer values (calibrated to degrees). Internal frictional forces were determined to be at maximum 2% of measured loading. Two separate experiments were performed to evaluate rabbit knees. First, normal right and left pairs of knees from four New Zealand White (NZW) rabbits were subjected to cyclic loading. An extension torque of 0.2 Nm was applied to each knee. The average change in knee joint extension from the first to the fifth cycle was 1.9 deg +/- 1.5 deg (mean +/- sd) with a total of 49 tests of these eight knees. The maximum extension of the four left knees (tested 23 times) was 14.6 deg +/- 7.1 deg, and of the four right knees (tested 26 times) was 12.0 deg +/- 10.9 deg. There was no significant difference in the maximum extension between normal left and right knees. In the second experiment, nine skeletally mature NZW rabbits had stable fractures of the femoral condyles of the right knee that were immobilized for five, six or 10 weeks. The left knee served as an unoperated control. Loss of knee joint

  14. Dynamic cortical activity during the perception of three-dimensional object shape from two-dimensional random-dot motion.

    Iwaki, Sunao; Bonmassar, Giorgio; Belliveau, John W

    2013-09-01

    Recent neuroimaging studies implicate that both the dorsal and ventral visual pathways, as well as the middle temporal (MT) areas which are critical for the perception of visual motion, are involved in the perception of three-dimensional (3D) structure from two-dimensional (2D) motion (3D-SFM). However, the neural dynamics underlying the reconstruction of a 3D object from 2D optic flow is not known. Here we combined magnetoencephalography (MEG) and functional MRI (fMRI) measurements to investigate the spatiotemporal brain dynamics during 3D-SFM. We manipulated parametrically the coherence of randomly moving groups of dots to create different levels of 3D perception and to study the associated changes in brain activity. At different latencies, the posterior infero-temporal (pIT), the parieto-occipital (PO), and the intraparietal (IP) regions showed increased neural activity during highly coherent motion conditions in which subjects perceived a robust 3D object. Causality analysis between these regions indicated significant causal influence from IP to pIT and from pIT to PO only in conditions where subjects perceived a robust 3D object. Current results suggest that the perception of a 3D object from 2D motion includes integration of global motion and 3D mental image processing, as well as object recognition that are accomplished by interactions between the dorsal and ventral visual pathways.

  15. Dynamic weight-bearing assessment of pain in knee osteoarthritis

    Klokker, Louise; Christensen, Robin; Wæhrens, Eva Elisabet Ejlersen

    2016-01-01

    BACKGROUND: The Osteoarthritis Research Society International (OARSI) has suggested to asses pain after specific activities consistently in clinical trials on knee OA. The Dynamic weight-bearing Assessment of Pain (DAP) assesses pain during activity (30 s of performing repeated deep knee-bends from...

  16. Rehabilitative Guidelines after Total Knee Arthroplasty: A Review.

    Mistry, Jaydev B; Elmallah, Randa D K; Bhave, Anil; Chughtai, Morad; Cherian, Jeffrey Jai; McGinn, Tanner; Harwin, Steven F; Mont, Michael A

    2016-04-01

    Rehabilitation following total knee arthroplasty (TKA) continues to pose a challenge for both patients and providers. In addition, guidelines vary considerably between institutions, which often leave therapy regimens to the discretion of the provider. The lack of clear guidelines for rehabilitation may contribute to inadequate recovery of strength and range-of-motion, resulting in less optimal functional outcomes. Therefore, the aim of this review was to highlight and discuss a variety of post-TKA rehabilitative modalities currently available and to provide evidence regarding efficacy and practicality. Specifically, we assessed the role of and evidence for exercise therapy, aquatic therapy, balance training, continuous passive motion, cold therapy and compression, neuromuscular electrical stimulation, transcutaneous electrical nerve stimulation, and instrument-assisted soft-tissue therapy. Additionally, we proposed general recommendations for rehabilitation after TKA, and as we specifically described active and obese patients, we have included guidelines for these subsets as well. Our review examines the various rehabilitative modalities to offer suggestions for recovery of strength and range-of-motion after TKA, with a focus on the early incorporation of exercise therapy, balance training, aquatic therapy, cryopneumatic therapy, neuromuscular electrical stimulation, and transcutaneous electrical nerve stimulation. Dedication and commitment to rehabilitation may help patients attain and exceed their preoperative activity levels.

  17. Total knee arthroplasty using computer assisted navigation in patients with severe valgus deformity of the knee

    SHAO Jun-jie; ZHANG Xian-long; WANG Qi; CHEN Yun-su; SHEN Hao; JIANG Yao

    2010-01-01

    Background Severe valgus deformity often has bone defect and laxity of the medial ligamentous, and total knee arthroplasty in severe valgus knee is, in most cases, more challenging for surgeons. The usefulness of a computer assisted navigation system in reestablishing the mechanical axis has been well established. Hence, the interest for surgeons is how the navigation system makes the procedure of total knee arthroplasty with severe valgus knee easier.Methods From June 2006 to March 2008 in Department of Joint Surgery, Shanghai Sixth People's Hospital, 6 patients (7 knees) with severe valgus knee underwent total knee arthroplasty using the Stryker Navigation system, which is an active wireless and imageless system. All the patients were followed up for 12 to 18 months after surgery. The X-ray radiographs for whole limbs were obtained on all patients to determine preoperative and postoperative alignments.Results A primary, posterior stabilized prosthesis was utilized in all cases. The average preoperative overall mechanical axis of the seven knees was 19.6°±4.6° of valgus (range 16° to 29°), and the average postoperative mechanical axis was 0.4°±0.7° (range 0.8° varus to 1.4° valgus ).Conclusions The navigation system is a very effective and useful tool for accurate intraoperative restoration of alignment in the face of significant deformity with valgus knee. To prevent component malposition, we did not reduce the knee before solidification of bone cement but controlled alignment using the navigation system up to implantation of the final component.

  18. Pathogenetic treatment for knee osteoarthrosis

    Marina Stanislavovna Svetlova

    2012-01-01

    Full Text Available The paper presents the results of studying the impact of long-term treatment with theraflex (a 3-year follow-up or alflutop (a 5-year follow-up in patients with knee osteoarthosis. Both drugs have been shown to exert a positive effect on the symptoms of the disease. It has been concluded that theraflex affects more actively the pathogenic mechanisms in the progression of gonarthrosis.

  19. Pathogenetic treatment for knee osteoarthrosis

    Marina Stanislavovna Svetlova

    2012-09-01

    Full Text Available The paper presents the results of studying the impact of long-term treatment with theraflex (a 3-year follow-up or alflutop (a 5-year follow-up in patients with knee osteoarthosis. Both drugs have been shown to exert a positive effect on the symptoms of the disease. It has been concluded that theraflex affects more actively the pathogenic mechanisms in the progression of gonarthrosis.

  20. Knee Bracing: What Works?

    ... knee. Some people use them to prevent knee injuries during sports. Braces are made from combinations of metal, foam, ... checker Get Started Related ArticlesCommon Sports InjuriesRead Article >>Injury RehabilitationCommon Sports InjuriesCommon sports injuries sideline many people each year, ...

  1. Pixel-by-pixel analysis of DCE-MRI curve shape patterns in knees of active and inactive juvenile idiopathic arthritis patients

    Hemke, Robert; Lavini, Cristina; Maas, Mario [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Nusman, Charlotte M. [University of Amsterdam, Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Berg, J.M. van den; Schonenberg-Meinema, Dieneke; Kuijpers, Taco W. [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Dolman, Koert M. [Department of Pediatric Rheumatology, Reade, Amsterdam (Netherlands); St. Lucas Andreas Hospital, Department of Pediatrics, Amsterdam (Netherlands); Rossum, Marion A.J. van [University of Amsterdam, Department of Pediatric Hematology, Immunology, Rheumatology and Infectious Disease, Emma Children' s Hospital AMC, Amsterdam (Netherlands); Department of Pediatric Rheumatology, Reade, Amsterdam (Netherlands)

    2014-07-15

    To compare DCE-MRI parameters and the relative number of time-intensity curve (TIC) shapes as derived from pixel-by-pixel DCE-MRI TIC shape analysis between knees of clinically active and inactive juvenile idiopathic arthritis (JIA) patients. DCE-MRI data sets were prospectively obtained. Patients were classified into two clinical groups: active disease (n = 43) and inactive disease (n = 34). Parametric maps, showing seven different TIC shape types, were created per slice. Statistical measures of different TIC shapes, maximal enhancement (ME), maximal initial slope (MIS), initial area under the curve (iAUC), time-to-peak (TTP), enhancing volume (EV), volume transfer constant (K {sup trans}), extravascular space fractional volume (V{sub e}) and reverse volume transfer constant (k{sub ep}) of each voxel were calculated in a three-dimensional volume-of-interest of the synovial membrane. Imaging findings from 77 JIA patients were analysed. Significantly higher numbers of TIC shape 4 (P = 0.008), median ME (P = 0.015), MIS (P = 0.001) and iAUC (P = 0.002) were observed in clinically active compared with inactive patients. TIC shape 5 showed higher presence in the clinically inactive patients (P = 0.036). The pixel-by-pixel DCE-MRI TIC shape analysis method proved capable of differentiating clinically active from inactive JIA patients by the difference in the number of TIC shapes, as well as the descriptive parameters ME, MIS and iAUC. (orig.)

  2. Clinical Outcomes in Men and Women following Total Knee Arthroplasty with a High-Flex Knee: No Clinical Effect of Gender

    Jeffrey M. Nassif

    2015-01-01

    Full Text Available While it is generally recognized that anatomical differences exist between the male and female knee, the literature generally refutes the clinical need for gender-specific total knee prostheses. It has been found that standard, unisex knees perform as well, or better, in women than men. Recently, high-flex knees have become available that mechanically accommodate increased flexion yet no studies have directly compared the outcomes of these devices in men and women to see if gender-based differences exist. We retrospectively compared the performance of the high-flex Vanguard knee (Biomet, Warsaw, IN in 716 male and 1,069 female knees. Kaplan-Meier survivorship was 98.5% at 5.6–5.7 years for both genders. After 2 years, mean improvements in Knee Society Knee and Function scores for men and women (50.9 versus 46.3; 26.5 versus 23.1 and corresponding SF-12 Mental and Physical scores (0.2 versus 2.2; 13.7 versus 12.2 were similar with differences not clinically relevant. Postoperative motion gains as a function of preoperative motion level were virtually identical in men and women. This further confirms the suitability of unisex total knee prostheses for both men and women.

  3. A framework for activity detection in wide-area motion imagery

    Porter, Reid B [Los Alamos National Laboratory; Ruggiero, Christy E [Los Alamos National Laboratory; Morrison, Jack D [Los Alamos National Laboratory

    2009-01-01

    Wide-area persistent imaging systems are becoming increasingly cost effective and now large areas of the earth can be imaged at relatively high frame rates (1-2 fps). The efficient exploitation of the large geo-spatial-temporal datasets produced by these systems poses significant technical challenges for image and video analysis and data mining. In recent years there has been significant progress made on stabilization, moving object detection and tracking and automated systems now generate hundreds to thousands of vehicle tracks from raw data, with little human intervention. However, the tracking performance at this scale, is unreliable and average track length is much smaller than the average vehicle route. This is a limiting factor for applications which depend heavily on track identity, i.e. tracking vehicles from their points of origin to their final destination. In this paper we propose and investigate a framework for wide-area motion imagery (W AMI) exploitation that minimizes the dependence on track identity. In its current form this framework takes noisy, incomplete moving object detection tracks as input, and produces a small set of activities (e.g. multi-vehicle meetings) as output. The framework can be used to focus and direct human users and additional computation, and suggests a path towards high-level content extraction by learning from the human-in-the-loop.

  4. Three-dimensional kinematic analysis of active cervical spine motion by using a multifaceted marker device.

    Tsunezuka, Hiroaki; Kato, Daishiro; Okada, Satru; Ishihara, Shunta; Shimada, Junichi

    2013-01-01

    Assessing cervical range of motion (CROM) is an important part of the clinical evaluation of patients with conditions such as whiplash syndrome. This study aimed to develop a convenient and accurate system involving multifaceted marker device (MMD)-based assessment of 3-dimensional (3D) dynamic coupled CROM and joint angular velocity. We used an infrared optical tracking system and our newly developed MMD that solved problems such as marker shielding and reflection angle associated with the optical tracking devices and enabled sequential and accurate analysis of the 3D dynamic movement of the polyaxial joint and other structurally complicated joints. The study included 30 asymptomatic young male volunteers (age, 22-27 years). The MMD consisted of 5 surfaces and 5 markers and was attached to the participant's forehead. We measured active CROM (axial rotation, flexion/extension, and lateral bending) and joint angular velocity by the MMD. The MMD was easy to use, safe for patients and operators, could be constructed economically, and generated accurate data such as dynamic coupled CROM and angular velocity.

  5. Active-flux based motion sensorless vector control of biaxial excitation generator/motor for automobiles (BEGA)

    Coroban-Schramel, Vasile; Boldea, Ion; Andreescu, Gheorghe-Daniel

    2009-01-01

    This paper proposes a novel, active-flux based, motion-sensorless vector control structure for biaxial excitation generator for automobiles (BEGA) for wide speed range operation. BEGA is a hybrid excited synchronous machine having permanent magnets on q-axis and a dc excitation on daxis. Using...... the active-flux concept the estimated rotor position is given by the sum of the active flux angle and torque angle. The active flux is calculated by subtracting the term Lq i s from the estimated stator flux vector. The experimental results validate the active flux-principle and show good performance...

  6. Musculoskeletal MR: knee

    Staebler, A.; Glaser, C.; Reiser, M. [Dept. of Diagnostic Radiology, Klinikum Grosshadern, Ludwig-Maximilian Universitaet Muenchen (Germany)

    2000-02-01

    Magnetic resonance imaging is the most sensitive, specific, and accurate noninvasive method for diagnosing internal derangement of the knee. During the past 15 years knowledge of pathologic conditions of the knee had evolved significantly. Beyond the basic principles of imaging knee injuries great impact was made on the understanding of indirect or collateral findings, even in rare diseases. In this article the spectrum of disorders of the knee are reviewed and an overview of the current literature is given. This includes considerations about how to achieve a high-standard MR imaging study of the knee, and principles of imaging anterior cruciate ligament and meniscal tears. A focus is put on distinct diseases including intra-articular and intraosseous ganglion cysts, iliotibial band friction syndrome, transient osteoporosis, osteonecrosis, osteochondritis dissecans, and imaging of the articular cartilage. (orig.)

  7. Pneumatic osteoarthritis knee brace.

    Stamenović, Dimitrije; Kojić, Milos; Stojanović, Boban; Hunter, David

    2009-04-01

    Knee osteoarthritis is a chronic disease that necessitates long term therapeutic intervention. Biomechanical studies have demonstrated an improvement in the external adduction moment with application of a valgus knee brace. Despite being both efficacious and safe, due to their rigid frame and bulkiness, current designs of knee braces create discomfort and difficulties to patients during prolonged periods of application. Here we propose a novel design of a light osteoarthritis knee brace, which is made of soft conforming materials. Our design relies on a pneumatic leverage system, which, when pressurized, reduces the excessive loads predominantly affecting the medial compartment of the knee and eventually reverses the malalignment. Using a finite-element analysis, we show that with a moderate level of applied pressure, this pneumatic brace can, in theory, counterbalance a greater fraction of external adduction moment than the currently existing braces.

  8. Improved knee flexion following high-flexion total knee arthroplasty

    Lionberger David R

    2012-06-01

    Full Text Available Abstract Background The application of new techniques and materials in total knee arthroplasty (TKA continue to be a primary focus in orthopedic surgery. The primary aim of the present study is to evaluate post TKA total range of motion (ROM among a group of patients who received a gender specific high-flexion design modification implant compared to a control group of patients who received non-gender specific implants. Methods and results The control group was comprised of 39 TKAs that were recruited pre-operatively and received the non-gender specific implant while the study group consisted of 39 TKAs who received gender specific implants. The study group yielded an improvement in mean post-operative ROM of 21° at 12 months, whereas the mean improvement in ROM among the control group was 11°. Thus, the study group had a 10° increased ROM improvement (91% over the control group (p = 0.00060. In addition, 100% of the subjects with gender specific high-flexion implants achieved greater or equal ROM post-operatively compared to 82% for the control cohort. Lastly, women who exhibited greater pre-operative ROM and lower body mass index (BMI were found to benefit the most with the gender specific prosthesis. Conclusion Our study demonstrates that among subjects with a normal BMI, the gender specific high-flexion knee implant is associated with increased ROM as compared to the non-gender specific non-high-flexion implant designs.

  9. Muscle co-contraction during gait in individuals with articular cartilage defects in the knee.

    Thoma, Louise M; McNally, Michael P; Chaudhari, Ajit M; Flanigan, David C; Best, Thomas M; Siston, Robert A; Schmitt, Laura C

    2016-07-01

    Increased muscle co-contraction during gait is common in individuals with knee pathology, and worrisome as it is known to amplify tibiofemoral compressive forces. While knees with articular cartilage defects (ACD) are more vulnerable to compressive forces, muscle co-contraction has never been reported in this population. The purpose of this study was to evaluate the extent to which individuals with ACDs in the knee demonstrate elevated quadriceps to hamstrings muscle co-contraction on the involved limb during gait compared to the uninvolved limb and to healthy controls. We also explored the impact of participant characteristics and knee impairments on co-contraction. Twenty-nine individuals with full-thickness knee ACDs (ACD group) and 19 healthy adults (control group) participated in this study. Participants performed five gait trials at self-selected speed, during which activity of the quadriceps and hamstrings muscles were collected with surface electromyography. Three-dimensional motion capture was used to define phases of gait. Quadriceps strength and self-reported outcomes were also assessed in the same session. There were no differences in quadriceps: hamstrings co-contraction between the ACD and control groups, or between the involved and uninvolved limb for the ACD group. For both ACD and control groups, co-contraction was highest in early stance and lowest in late stance. Quadriceps strength was consistently the strongest predictor of muscle co-contraction in both the ACD and the control groups, with individuals with lower strength demonstrating greater co-contraction. Further study is needed to understand the effect of increased muscle co-contraction on joint compressive forces in the presence of varied quadriceps strength.

  10. TIBIOFEMORAL KINEMATICS AND CONDYLAR MOTION DURING THE STANCE PHASE OF GAIT

    Kozanek, Michal; Hosseini, Ali; Liu, Fang; Van de Velde, Samuel K.; Gill, Thomas J.; Rubash, Harry E.; Li, Guoan

    2009-01-01

    Accurate knowledge of the dynamic knee motion in vivo is instrumental for understanding normal and pathological function of the knee joint. However, interpreting motion of the knee joint during gait in other than the sagittal plane remains controversial. In this study, we utilized the dual fluoroscopic imaging technique to investigate the six-degree of freedom kinematics and condylar motion of the knee during the stance phase of treadmill gait in eight healthy volunteers at a speed of 0.67m/s...

  11. Soft tissue twisting injuries of the knee

    Magee, T.; Shapiro, M. [Neuroimaging Inst., Melbourne, FL (United States)

    2001-08-01

    Twisting injuries occur as a result of differential motion of different tissue types in injuries with some rotational force. These injuries are well described in brain injuries but, to our knowledge, have not been described in the musculoskeletal literature. We correlated the clinical examination and MR findings of 20 patients with twisting injuries of the soft tissues around the knee. Design and patients: We prospectively followed the clinical courses of 20 patients with knee injuries who had clinical histories and MR findings to suggest twisting injuries of the subcutaneous tissues. Patients with associated internal derangement of the knee (i.e., meniscal tears, ligamentous or bone injuries) were excluded from this study. MR findings to suggest twisting injuries included linear areas of abnormal dark signal on T1-weighted sequences and abnormal bright signal on T2-weighted or short tau inversion recovery (STIR) sequences and/or signal to suggest hemorrhage within the subcutaneous tissues. These MR criteria were adapted from those established for indirect musculotendinous junction injuries. Results: All 20 patients presented with considerable pain that suggested internal derangement on physical examination by the referring orthopedic surgeons. All presented with injuries associated with rotational force. The patients were placed on a course of protected weight-bearing of the affected extremity for 4 weeks. All patients had pain relief by clinical examination after this period of protected weight-bearing. Twisting injuries of the soft tissues can result in considerable pain that can be confused with internal derangement of the knee on physical examination. Soft tissue twisting injuries need to be recognized on MR examinations as they may be the cause of the patient's pain despite no MR evidence of internal derangement of the knee. The demonstration of soft tissue twisting injuries in a patient with severe knee pain but no documented internal derangement on MR

  12. Ground motion parameters of Shillong plateau: One of the most seismically active zones of northeastern India

    Saurabh Baruah; Santanu Baruah; Naba Kumar Gogoi; Olga Erteleva; Felix Aptikaev; J.R.Kayal

    2009-01-01

    Strong ground motion parameters for Shillong plateau of northeastern India are examined. Empirical relations are obtained for main parameters of ground motions as a function of earthquake magnitude, fault type, source depth, velocity characterization of medium and distance. Correlation between ground motion parameters and characteristics of seismogenic zones are established. A new attenuation relation for peak ground acceleration is developed, which predicts higher expected PGA in the region. Parameters of strong motions, particularly the predominant periods and duration of vibrations, depend on the morphology of the studied area. The study measures low estimates of logarithmic width in Shillong plateau. The attenuation relation estimated for pulse width critically indicates increased pulse width dependence on the logarithmic distance which accounts for geometrical spreading and anelastic attenuation.

  13. Surgery For The Arthritic Knee

    Gross, Allan E.

    1985-01-01

    The optimal surgical procedure for the arthritic knee depends upon the type of arthritis and the patient. If the patient is ‘high demand’ (i.e., relatively active and young), and has incongruous arthritis (in either the medial or lateral compartments but not both), then realignment by osteotomy transfers the weight to the healthy compartment. If the osteotomy is successful, the patient may continue a physically demanding lifestyle. Knee replacement is indicated if the patient is ‘low demand’ (i.e., elderly or suffering from multiple joint disease) and has congruous arthritis, with destruction of both weight-bearing compartments. Knee replacement does not allow the same activity level as realignment but, fortunately, the low demand patient tends to have congruous disease (e.g., rheumatoid arthritis) and the high demand patient incongruous disease (e.g., osteoarthritis). ImagesFig. 1Fig. 2Fig. 3Fig. 4Fig. 5Figs. 6A-BFigs. 6C-DFig. 7Fig. 8Fig. 9 PMID:21274227

  14. Inverse Dynamics and the Immeasurable Motions

    Rasmussen, John; Andersen, Michael Skipper; Damsgaard, Michael

    the precise 3-D marker locations, certain movements are inherently difficult to register, for instance the movement of the scapula relative to the thorax or glenohumeral superior migration. This paper, however, focuses on the knee. Knee flexion/extension is a large articulation in most practical cases......, typically gait, and a well-conducted experiment with a good-quality motion capture system will register this degree-of-freedom with sufficient accuracy for most applications. However, it is known from bone pin studies (Benoit et al. 2006) that the knee has significant movements additional to flexion...

  15. Wearable Sensor-Based Rehabilitation Exercise Assessment for Knee Osteoarthritis

    Kun-Hui Chen

    2015-02-01

    Full Text Available Since the knee joint bears the full weight load of the human body and the highest pressure loads while providing flexible movement, it is the body part most vulnerable and susceptible to osteoarthritis. In exercise therapy, the early rehabilitation stages last for approximately six weeks, during which the patient works with the physical therapist several times each week. The patient is afterwards given instructions for continuing rehabilitation exercise by him/herself at home. This study develops a rehabilitation exercise assessment mechanism using three wearable sensors mounted on the chest, thigh and shank of the working leg in order to enable the patients with knee osteoarthritis to manage their own rehabilitation progress. In this work, time-domain, frequency-domain features and angle information of the motion sensor signals are used to classify the exercise type and identify whether their postures are proper or not. Three types of rehabilitation exercise commonly prescribed to knee osteoarthritis patients are: Short-Arc Exercise, Straight Leg Raise, and Quadriceps Strengthening Mini-squats. After ten subjects performed the three kinds of rehabilitation activities, three validation techniques including 10-fold cross-validation, within subject cross validation, and leave-one-subject cross validation are utilized to confirm the proposed mechanism. The overall recognition accuracy for exercise type classification is 97.29% and for exercise posture identification it is 88.26%. The experimental results demonstrate the feasibility of the proposed mechanism which can help patients perform rehabilitation movements and progress effectively. Moreover, the proposed mechanism is able to detect multiple errors at once, fulfilling the requirements for rehabilitation assessment.

  16. Wearable Sensor-Based Rehabilitation Exercise Assessment for Knee Osteoarthritis

    Chen, Kun-Hui; Chen, Po-Chao; Liu, Kai-Chun; Chan, Chia-Tai

    2015-01-01

    Since the knee joint bears the full weight load of the human body and the highest pressure loads while providing flexible movement, it is the body part most vulnerable and susceptible to osteoarthritis. In exercise therapy, the early rehabilitation stages last for approximately six weeks, during which the patient works with the physical therapist several times each week. The patient is afterwards given instructions for continuing rehabilitation exercise by him/herself at home. This study develops a rehabilitation exercise assessment mechanism using three wearable sensors mounted on the chest, thigh and shank of the working leg in order to enable the patients with knee osteoarthritis to manage their own rehabilitation progress. In this work, time-domain, frequency-domain features and angle information of the motion sensor signals are used to classify the exercise type and identify whether their postures are proper or not. Three types of rehabilitation exercise commonly prescribed to knee osteoarthritis patients are: Short-Arc Exercise, Straight Leg Raise, and Quadriceps Strengthening Mini-squats. After ten subjects performed the three kinds of rehabilitation activities, three validation techniques including 10-fold cross-validation, within subject cross validation, and leave-one-subject cross validation are utilized to confirm the proposed mechanism. The overall recognition accuracy for exercise type classification is 97.29% and for exercise posture identification it is 88.26%. The experimental results demonstrate the feasibility of the proposed mechanism which can help patients perform rehabilitation movements and progress effectively. Moreover, the proposed mechanism is able to detect multiple errors at once, fulfilling the requirements for rehabilitation assessment. PMID:25686308

  17. Intra-Articular Knee Contact Force Estimation During Walking Using Force-Reaction Elements and Subject-Specific Joint Model.

    Jung, Yihwan; Phan, Cong-Bo; Koo, Seungbum

    2016-02-01

    Joint contact forces measured with instrumented knee implants have not only revealed general patterns of joint loading but also showed individual variations that could be due to differences in anatomy and joint kinematics. Musculoskeletal human models for dynamic simulation have been utilized to understand body kinetics including joint moments, muscle tension, and knee contact forces. The objectives of this study were to develop a knee contact model which can predict knee contact forces using an inverse dynamics-based optimization solver and to investigate the effect of joint constraints on knee contact force prediction. A knee contact model was developed to include 32 reaction force elements on the surface of a tibial insert of a total knee replacement (TKR), which was embedded in a full-body musculoskeletal model. Various external measurements including motion data and external force data during walking trials of a subject with an instrumented knee implant were provided from the Sixth Grand Challenge Competition to Predict in vivo Knee Loads. Knee contact forces in the medial and lateral portions of the instrumented knee implant were also provided for the same walking trials. A knee contact model with a hinge joint and normal alignment could predict knee contact forces with root mean square errors (RMSEs) of 165 N and 288 N for the medial and lateral portions of the knee, respectively, and coefficients of determination (R2) of 0.70 and -0.63. When the degrees-of-freedom (DOF) of the knee and locations of leg markers were adjusted to account for the valgus lower-limb alignment of the subject, RMSE values improved to 144 N and 179 N, and R2 values improved to 0.77 and 0.37, respectively. The proposed knee contact model with subject-specific joint model could predict in vivo knee contact forces with reasonable accuracy. This model may contribute to the development and improvement of knee arthroplasty.

  18. A randomized clinical trial of a peri-operative behavioral intervention to improve physical activity adherence and functional outcomes following total knee replacement

    Zheng Hua

    2011-10-01

    Full Text Available Abstract Background Total knee replacement (TKR is a common and effective surgical procedure to relieve advanced knee arthritis that persists despite comprehensive medical treatment. Although TKR has excellent technical outcomes, significant variation in patient-reported functional improvement post-TKR exists. Evidence suggests that consistent post-TKR exercise and physical activity is associated with functional gain, and that this relationship is influenced by emotional health. The increasing use of TKR in the aging US population makes it critical to find strategies that maximize functional outcomes. Methods/Design This randomized clinical trial (RCT will test the efficacy of a theory-based telephone-delivered Patient Self-Management Support intervention that seeks to enhance adherence to independent exercise and activity among post- TKR patients. The intervention consists of 12 sessions, which begin prior to surgery and continue for approximately 9 weeks post-TKR. The intervention condition will be compared to a usual care control condition using a randomized design and a probabilistic sample of men and women. Assessments are conducted at baseline, eight weeks, and six- and twelve- months. The project is being conducted at a large healthcare system in Massachusetts. The study was designed to provide greater than 80% power for detecting a difference of 4 points in physical function (SF36/Physical Component Score between conditions (standard deviation of 10 at six months with secondary outcomes collected at one year, assuming a loss to follow up rate of no more than 15%. Discussion As TKR use expands, it is important to develop methods to identify patients at risk for sub-optimal functional outcome and to effectively intervene with the goal of optimizing functional outcomes. If shown efficacious, this peri-TKR intervention has the potential to change the paradigm for successful post-TKR care. We hypothesize that Patient Self-Management Support

  19. A Passive Dynamic Walking Model Based on Knee-Bend Behaviour: Stability and Adaptability for Walking Down Steep Slopes

    Kang An

    2013-10-01

    Full Text Available This paper presents a passive dynamic walking model based on knee-bend behaviour, which is inspired by the way human beings walk. The length and mass parameters of human beings are used in the walking model. The knee-bend mechanism of the stance leg is designed in the phase between knee-strike and heel- strike. q* which is the angular difference of the stance leg between the two events, knee-strike and knee-bend, is adjusted in order to find a stable walking motion. The results show that the stable periodic walking motion on a slope of r <0.4 can be found by adjusting q*. Furthermore, with a particular q* in the range of 0.12motion is more stable and adaptable than the conventional walking motion, especially for steep slopes.

  20. Outcomes of Varus Valgus Constrained Versus Rotating-Hinge Implants in Total Knee Arthroplasty.

    Malcolm, Tennison L; Bederman, S Samuel; Schwarzkopf, Ran

    2016-01-01

    The stability of a total knee arthroplasty is determined by the ability of the prosthesis components in concert with supportive bone and soft tissue structures to sufficiently resist deforming forces transmitted across the knee joint. Constrained prostheses are used in unstable knees due to their ability to resist varus and valgus transformative forces across the knee. Constraint requires inherent rigidity, which can facilitate early implant failure. The purpose of this study was to describe the comparative indications for surgery and postoperative outcomes of varus valgus constrained knee (VVK) and rotating-hinge knee (RHK) total knee arthroplasty prostheses. Seven retrospective observational studies describing 544 VVK and 254 RHK patients with an average follow-up of 66 months (range, 7-197 months) were evaluated. Patients in both groups experienced similar failure rates (P=.74), ranges of motion (P=.81), and Knee Society function scores (P=.29). Average Knee Society knee scores were 4.2 points higher in VVK patients compared with RHK patients, indicating minimal mid-term clinical differences may exist (P<.0001). Absent collateral ligament support is an almost universal indication for RHK implantation vs VVK. Constrained device implantation is routinely guided by inherent stability of the knee, and, when performed, similar postoperative outcomes can be achieved with VVK and RHK prostheses.

  1. High-intensity mechanical therapy for loss of knee extension for worker's compensation and non-compensation patients

    Dempsey Amanda L

    2010-10-01

    Full Text Available Abstract Background Knee flexion contractures have been associated with increased pain and a reduced ability to perform activities of daily living. Contractures can be treated either surgically or conservatively, but these treatment options may not be as successful with worker's compensation patients. The purposes of retrospective review were to 1 determine the efficacy of using adjunctive high-intensity stretch (HIS mechanical therapy to treat flexion contractures, and 2 compare the results between groups of worker's compensation and non-compensation patients. Methods Fifty-six patients (19 women, 37 men, age = 51.5 ± 17.0 years with flexion contractures were treated with HIS mechanical therapy as an adjunct to outpatient physical therapy. Mechanical therapy was only prescribed for those patients whose motion had reached a plateau when treated with physical therapy alone. Patients were asked to perform six, 10-minute bouts of end-range stretching per day with the ERMI Knee Extensionater(r (ERMI, Inc., Atlanta, GA. Passive knee extension was recorded during the postoperative visit that mechanical therapy was prescribed, 3 months after beginning mechanical therapy, and at the most recent follow-up. We used a mixed-model 2 × 3 ANOVA (group × time to evaluate the change in passive knee extension between groups over time. Results Regardless of group, the use of adjunctive HIS mechanical therapy resulted in passive knee extension deficits that significantly improved from 10.5° ± 5.2° at the initial visit to 2.6° ± 3.5° at the 3 month visit (p Conclusions We conclude that the adjunctive use of HIS mechanical therapy is an effective treatment option for patients with knee flexion contractures, regardless of whether the patient is being treated as part of a worker's compensation claim or not.

  2. Human Control Law and Brain Activity of Voluntary Motion by Utilizing a Balancing Task with an Inverted Pendulum

    Satoshi Suzuki

    2010-01-01

    Full Text Available Human characteristics concerning voluntary motion control are investigated, because this motion is fundamental for the machine operation and human-computer system. Using a force feedback haptic device and a balancing task of a virtual inverted pendulum, participants were trained in the task, and hand motion/force was measured, and brain activity was monitored. First, through brain analysis by near-infrared spectroscopy (NIRS and motion analysis of the pendulum, we identified a participant who was the most expert. Next, control characteristics of the most expert were investigated by considering the operational force and delay factor of a human. As a result, it was found that predictive control based on velocity information was used predominantly although a perception feedback control against the pendulum posture worked. And it was shown that an on-off intermittency control, which was a strategy for the skilled balancing, can be described well by a liner model involving two types of time shifts for the position and velocity. In addition, it was confirmed that the cortex activity for observation in an ocular motor control area and visual processing area was strong to enhance above-mentioned control strategies.

  3. Knee kinetic pattern during gait and anterior knee pain before and after rehabilitation in patients with patellofemoral pain syndrome.

    Claudon, B; Poussel, M; Billon-Grumillier, C; Beyaert, C; Paysant, J

    2012-05-01

    Patellofemoral pain is likely due to compressive force acting on the patella related in turn to knee extension moment. The latter variable was assumed to be (i) reduced during short-distance free walking in case of patellofemoral pain syndrome and (ii) increased after therapeutic pain reduction. Peak knee extension moment at beginning of stance phase was recorded by three-dimensional gait analysis in 22 controls and in 23 patients with patellofemoral pain syndrome before and after rehabilitation of knee extensors and flexors to reduce the pain. Pain would occur mainly in stressful activities such as stair negotiation or squatting and was quantified by the anterior knee pain scale. Peak knee extension moment was significantly reduced in all the patients before treatment (n=23) compared to controls, although no one had pain during free walking. In the 17 patients who experienced significant post-rehabilitation pain reduction in their stressful activities, the peak knee extension moment was significantly reduced before treatment compared to controls and significantly increased after treatment, reaching values similar to control values. The peak knee extension moment during free walking appears to be a good kinetic variable related to a compensatory mechanism limiting or avoiding anterior knee pain and may be of interest in assessing knee dynamics alteration in patients with PFPS.

  4. Highly conforming polyethylene inlays reduce the in vivo variability of knee joint kinematics after total knee arthroplasty.

    Daniilidis, Kiriakos; Skwara, Adrian; Vieth, Volker; Fuchs-Winkelmann, Susanne; Heindel, Walter; Stückmann, Volker; Tibesku, Carsten O

    2012-08-01

    The use of highly conforming polyethylene inlays in total knee arthroplasty (TKA) provides improved anteroposterior stability. The aim of this fluoroscopic study was to investigate the in vivo kinematics during unloaded and loaded active extension with a highly conforming inlay and a flat inlay after cruciate retaining (CR) total knee arthroplasty (TKA). Thirty one patients (50 knees) received a fixed-bearing cruciate retaining total knee arthroplasty (Genesis II, Smith & Nephew, Schenefeld, Germany) for primary knee osteoarthritis. Twenty two of them received a flat polyethylene inlay (PE), nine a deep dished PE and 19 were in the control group (physiological knees). The mean age at the time of surgery was 62 years. Dynamic examination with fluoroscopy was performed to assess the "patella tendon angle" in relation to the knee flexion angle (measure of anteroposterior translation) and the "kinematic index" (measure of reproducibility). Fluoroscopy was performed under active extension and flexion, during unloaded movement, and under full weight bearing, simulated by step climbing. No significant difference was observed between both types of polyethylene inlay designs and the physiological knee during unloaded movement. Anteroposterior (AP) instability was found during weight-bearing movement. The deep-dish inlay resulted in lower AP translation and a non-physiological rollback. Neither inlay types could restore physiological kinematics of the knee. Despite the fact that deep dished inlays reduce the AP translation, centralisation of contact pressure results in non-physiological rollback. The influence of kinematic pattern variability on clinical results warrants further investigation.

  5. Method and effect of total knee arthroplasty osteotomy and soft tissue release for serious knee joint space narrowing

    Yulou Si

    2015-01-01

    Full Text Available To discuss the method and effect of total knee arthroplasty osteotomy and soft tissue release for serious knee joint space narrowing. Clinical data of 80 patients from October 2013 to December 2014 was selected with a retrospective method. All patients have undergone total knee arthroplasty. Then the X-rays plain film in weight loading was measured before and after operation and osteotomy was performed accurately according to the knee joint scores and the conditions of lower limb alignments. The average angle of tibial plateau osteotomy of postoperative patients was 4.3°, and the corrective angle of soft tissue balancing was 10.7°; the postoperative patients’ indicies including range of joint motion, knee joint HSS score, angle between articular surfaces, tibial angle, femoral-tibial angle and flexion contracture were distinctly better than the preoperative indicies (p<0.05 and the differences were statistically significant; the postoperative patients’ flexion contracture and range of joint motion were distinctly better than the preoperative indicies (p<0.05 and the differences were statistically significant. The effective release of the soft tissue of the posterior joint capsule under direct vision can avoid excess osteotomy and get satisfactory knee replacement space without influencing the patients’ joint recovery.

  6. INFLUENCE OF GONARTHROSIS ON KINEMATICS INDICATORS OF THE KNEE JOINT

    S. I. Loginov

    2016-01-01

    Full Text Available Aim. To establish peculiarity of the influence of gonarthrosis on kinematics indices of the knee joint at people at the age of 45–60 with the help of markless motion method.Materials and methods. In the research 81 people took part. In the group of the control entered 42 people without symptomatic evidences of gonarthrosis, in the experimental group – 39 people with gonarthrosis of the 1 and 2 degrees at the age of 40 to 65. With the help of the markless motion method and software Brekel Pro Body» was made biomechanical analysis of the kinematics of knee joints.Results. It is established that people at the age of 40 to 65, suffering with gonarthrosis have authentically more angular moments of lateral mode of motions and rotations in knee joints.Conclusion. Under analysis of the kinematics of knee joints, between the control and the experimental groups were fixed significant differences (t-test, p < 0,01. Besides there were fixed differences between dominant and non-dominant limbs, which mean that the force of muscles of lower limbs can also be a modificative factor, which influences on the strain in joints that potentially can lead to the development and/or advance of degenerative damage in the knee joint. 

  7. Bioinspired Knee Joint for a Power-Assist Suit

    Takehito Kikuchi

    2016-01-01

    Full Text Available Movement of the knee joint of a human includes rolling and sliding. There also exist rotations in the frontal and horizontal planes. To assist the standing movement of a human, we developed a bioinspired knee joint and torque adjustment mechanism. We evaluated the motion, torque characteristics, and stress of the developed mechanism. This joint allows deep flexion of the knee with small resistance for both the user and the device. In addition, in spite of 33% error in deep flexion, the measured torque over less than 120 degrees fits the designed torque curve. We conducted evaluation tests for a human subject. The electromyogram (EMG of musculus rectus femoris was measured during standing with or without the assistance. The result shows 30% and 63% reduction with the assistance from 100-degree and 80-degree knee angles, respectively. In addition, the proposed device reduced up to 80% of stress in the frontal plane during standing.

  8. A Case Report on Bilateral Knee Coverage Following Septic Arthritis: Lateral Distal Thigh Island Flap and Medial Head Gastrocnemius Flap Methods

    Abdolrazaghi

    2016-03-01

    Full Text Available Introduction Septic arthritis is the rheumatological and orthopedic emergency that causes the most difficulties with joints–especially knee and hip joints. The clinical symptoms include pain, swelling, inflammation, stiffness, and a limited range of motion in both active and passive joints. Debridement of the necrotic tissue is one beneficial method for septic arthritis treatment, although soft tissue defects around joints are a challenging issue for surgeons. Our purpose was to investigate the consequences of two flap surgery methods undertaken to repair soft tissue damaged during knee joint debridement caused by septic arthritis. Case Presentation This is a case report concerning a patient who had septic arthritis in the knee area and so underwent soft tissue surgery. The reconstruction methods were not the same for both knees as the lateral distal thigh island flap reparation method was used on the left knee and the medial head gastrocnemius flap method was utilized on the right. We then investigated the results and outcomes of the surgery three months later. Conclusions Lower extremity movement extent was carefully evaluated and, in respect to muscle strength, the patient was able to walk independently three months after the surgery. The patient’s balance was studied and the results showed moderate levels of stability.

  9. Low-intensity eccentric contractions attenuate muscle damage induced by subsequent maximal eccentric exercise of the knee extensors in the elderly.

    Chen, Trevor C; Tseng, Wei-Chin; Huang, Guan-Ling; Chen, Hsin-Lian; Tseng, Kou-Wei; Nosaka, Kazunori

    2013-04-01

    This study investigated whether low-intensity eccentric contractions of the knee extensors would attenuate the magnitude of muscle damage induced by maximal eccentric exercise of the same muscle performed 7 days later using elderly individuals. Healthy older men (66.4 ± 4.6 years) were assigned to control or experimental (Exp) group (n = 13 per group). The control group performed six sets of ten maximal eccentric contractions (MaxECC) of the knee extensors of non-dominant leg. The Exp group performed six sets of ten low-intensity eccentric contractions of the knee extensors on a leg extension machine by lowering a weight of 10 % maximal voluntary isometric knee extension strength (10 %ECC) 7 days prior to MaxECC. Changes in maximal voluntary isokinetic concentric torque (MVC-CON), angle at peak torque, range of motion (ROM), upper thigh circumference, muscle soreness, plasma creatine kinase activity and myoglobin (Mb) concentration and B-mode ultrasound echo-intensity before and for 5 days after MaxECC were compared between groups by a mixed factor ANOVA. No significant changes in any variables were observed following 10 %ECC. Following MaxECC, all variables changed significantly, and changes in all variables except for angle at peak torque were significantly different between groups. MVC-CON and ROM decreased smaller and recovered faster (P eccentric contractions was effective for attenuating muscle damage induced by subsequent MaxECC of the knee extensors for elderly individuals.

  10. Contributory factors to the results of gravity-assisted pivot-shift test for anterior cruciate ligament injury: the significance of muscle torque around the knee.

    Hiraoka, Hisatada; Yashiki, Motohisa; Sakai, Hiroya

    2008-03-01

    Gravity-assisted pivot-shift (GAPS) test is a newly advocated test for anterior cruciate ligament (ACL) injury. It induces anterolateral rotatory instability with valgus stress to the knee applied by gravitational force during patient's active knee motion. We investigated prospectively the relationships between the results of the GAPS test and the possible contributory factors and sought to clarify the determinant factors of the GAPS test. A total of 54 knee joints of 54 patients with unilateral ACL injury (29 males, 25 females, average 23.4 +/- 9.0 years old) were enrolled in this study and were divided into two groups, i.e., positive GAPS test group and negative GAPS test group. Muscle torque around the knee joints measured before surgery, configuration of the femoral condyle and tibial posterior slope angle measured on lateral radiograph, and other clinical factors were compared between the two groups using Mann-Whitney U test or chi-square test. According to the results of these analyses, factors having a statistically significant difference were additionally evaluated using multiple logistic regression analysis to reveal items with strong relevance to a positive GAPS test. The results of the multiple logistic regression analysis showed that the flexor/extensor peak torque ratio of contralateral uninjured knees and sex had a significant correlation with the results of the GAPS test. The relatively less flexor muscle torque compared with extensor muscle torque, and being a female patient were considered to be the determinant factors of a positive GAPS test.

  11. Outcome of knee injuries in general practice : 1-year follow-up

    Wagemakers, Harry P. A.; Luijsterburg, Pim A. J.; Heintjes, Edith M.; Berger, Marjolein Y.; Verhaar, Jan; Koes, Bart W.; Bierma-Zeinstra, Sita M. A.

    2010-01-01

    Background Knee injuries may lead to pain and to functional limitations in the activities of daily living. Patients with knee injuries are frequently seen in general practice; however, the outcome and management in these patients is not known. Aim To assess the outcome and management of knee injurie

  12. Energy harvesting from walking motion of a humanoid robot using a piezoelectric composite

    Cha, Youngsu; Hong, Seokmin

    2016-10-01

    In this paper, we investigate the energy harvesting of a piezoelectric composite in a knee pad during walking motion. We use a humanoid robot as a test bed for the experiments using the knee pad. The humanoid wears the knee pad hosting the piezoelectric composite, and its operating knee motion mimics the walking based on the data captured from a human. The use of the humanoid enables the motion to be completely repeatable. We quantitatively study the energy harvesting by using the repeated motion. An electromechanical model for the piezoelectric energy harvester is used to estimate power transferred to varied load resistances under the repeated knee motion. With a good agreement between the experiments and the model predictions, we demonstrate power harvesting on the order of ten microWatts.

  13. Effect of Mulligan's and Kinesio knee taping on adolescent ballet dancers knee and hip biomechanics during landing.

    Hendry, D; Campbell, A; Ng, L; Grisbrook, T L; Hopper, D M

    2015-12-01

    Taping is often used to manage the high rate of knee injuries in ballet dancers; however, little is known about the effect of taping on lower-limb biomechanics during ballet landings in the turnout position. This study investigated the effects of Kinesiotape (KT), Mulligan's tape (MT) and no tape (NT) on knee and hip kinetics during landing in three turnout positions. The effect of taping on the esthetic execution of ballet jumps was also assessed. Eighteen pain-free 12-15-year-old female ballet dancers performed ballet jumps in three turnout positions, under the three knee taping conditions. A Vicon Motion Analysis system (Vicon Oxford, Oxford, UK) and Advanced Mechanical Technology, Inc. (Watertown, Massa chusetts, USA) force plate collected lower-limb mechanics. The results demonstrated that MT significantly reduced peak posterior knee shear forces (P = 0.025) and peak posterior (P = 0.005), medial (P = 0.022) and lateral (P = 0.014) hip shear forces compared with NT when landing in first position. KT had no effect on knee or hip forces. No significant differences existed between taping conditions in all landing positions for the esthetic measures. MT was able to reduce knee and the hip forces without affecting the esthetic performance of ballet jumps, which may have implications for preventing and managing knee injuries in ballet dancers.

  14. Mechanically Activated Motion of a Single Self-Propelled Polymeric Microcapsule

    Kolmakov, German; Schaefer, Alexander; Aranson, Igor; Balazs, Anna

    2011-03-01

    Using a hybrid computational approach, we demonstrate that a single nanoparticle-filled microcapsule on a rigid substrate can undergo self-sustained motion in response to initial mechanical deformation. Nanoparticles released from the capsule modify the underlying substrate and the adhesion gradients of the nanoparticle concentration formed at the surface sustain the motion of the capsule. The permeability of the microcapsule's shell increases with its deformation and therefore, more deformed microcapsules release nanoparticles at higher rates. An initial, non-uniform mechanical deformation of the capsule by an applied force causes an asymmetry in the nanoparticle distribution on the substrate that initiates the microcapsule motion. We also develop a two-dimensional model of the phenomenon within the phase-field approximation and compare the results of the two approaches.

  15. Combined anterior cruciate ligament and posterolateral reconstruction of the knee using allograft tissue in chronic knee injuries.

    Fanelli, Gregory C; Fanelli, David G; Edson, Craig J; Fanelli, Matthew G

    2014-10-01

    Combined anterior cruciate ligament (ACL) and posterolateral injury of the knee can result in significant functional instability for the affected individual. Both components of the instability must be treated to maximize the probability of success for the surgical procedure. Higher failure rates of the ACL reconstruction have been reported when the posterolateral instability has been left untreated. The purpose of this article is to describe our surgical technique, and present the results of 34 chronic combined ACL posterolateral reconstructions in 34 knees using allograft tissue, and evaluating these patient outcomes with KT 1000 knee ligament arthrometer, Lysholm, Tegner, and Hospital for Special Surgery knee ligament rating scales. In addition, observations regarding patient demographics with combined ACL posterolateral instability, postoperative range of motion loss, postinjury degenerative joint disease, infection rate, return to function, and the use of radiated and nonirradiated allograft tissues will be presented.

  16. A Comparison of Two Motion Sensors for the Assessment of Free-Living Physical Activity of Adolescents

    Roman Cuberek

    2010-04-01

    Full Text Available This study assessed and compared the daily step counts recorded by two different motion sensors in order to estimate the free-living physical activity of 135 adolescent girls. Each girl concurrently wore a Yamax pedometer and an ActiGraph accelerometer (criterion measure every day for seven consecutive days. The convergent validity of the pedometer can be considered intermediate when used to measure the step counts in free-living physical activity; but should be considered with caution when used to classify participants’ step counts into corresponding physical activity categories because of a likelihood of ‘erroneous’ classification in comparison with the accelerometer.

  17. Stance control knee mechanism for lower-limb support in hybrid neuroprosthesis

    Curtis S. To, PhD

    2011-08-01

    Full Text Available A hydraulic stance control knee mechanism (SCKM was developed to fully support the knee against flexion during stance and allow uninhibited motion during swing for individuals with paraplegia using functional neuromuscular stimulation (FNS for gait assistance. The SCKM was optimized for maximum locking torque for body-weight support and minimum resistance when allowing for free knee motion. Ipsilateral and contralateral position and force feedback were used to control the SCKM. Through bench and nondisabled testing, the SCKM was shown to be capable of supporting up to 70 N-m, require no more than 13% of the torque achievable with FNS to facilitate free motion, and responsively and repeatedly unlock under an applied flexion knee torque of up to 49 N-m. Preliminary tests of the SCKM with an individual with paraplegia demonstrated that it could support the body and maintain knee extension during stance without the stimulation of the knee extensor muscles. This was achieved without adversely affecting gait, and knee stability was comparable to gait assisted by knee extensor stimulation during stance.

  18. The Effect of Hip Bracing on Gait in Patients with Medial Knee Osteoarthritis

    David Wallace

    2012-01-01

    Full Text Available Objective. Impaired hip motion has been associated with heightened medial knee joint loading in patients with knee osteoarthritis (OA. A hip external rotation strap designed to pull the femur into external rotation and abduction may serve as one protective mechanism. The primary aim of our study is to determine if the strap decreases medial knee joint loading during level walking in people with knee OA. Design. This study is a single-day repeated measures design. Methods. 15 volunteers with medial knee OA underwent motion analysis data collection during two randomly assigned walking conditions: (1 wearing the strap and (2 control (no strap. Primary outcome measures were peak pelvis, hip and knee joint motions, and torques. These outcomes were averaged across five trials for each condition. Results. Hip abduction (<0.01, trunk lean towards the stance limb (=0.04 and pelvic tilt (=0.02 significantly increased with the strap versus control trials. Knee adduction loading did not significantly change with the strap (=0.33. Conclusion. The use of the hip external rotation strap resulted in angular changes at the hip and pelvis which may be beneficial for patients with medial knee osteoarthritis.

  19. Movement detection impaired in patients with knee osteoarthritis compared to healthy controls: A cross-sectional case-control study

    Lund, H.; Juul-Kristensen, B.; Hansen, K.;

    2008-01-01

    compared to healthy participants' right elbows (AE: 2.15(o) [0.20(o)] versus 1.45(o) [0.15(o)], p=0.011). No significant difference between healthy women and OA patients regarding the left elbow for TDPM, or JPS was observed. The present age-controlled, cross-sectional study suggests......The purpose of this study was to clarify whether osteoarthritis (OA) patients have a localized or a generalized reduction in proprioception. Twenty one women with knee OA (mean age [SD]: 57.1 [12.0] years) and 29 healthy women (mean age [SD]: 55.3 [10.1] years) had their joint position sense (JPS......) and threshold to detection of a passive movement (TDPM) measured in both knees and elbows. JPS was measured as the participant's ability to actively reproduce the position of the elbow and knee joints. TDPM was measured as the participant's ability to recognize a passive motion of the elbow and knee joints...

  20. Active Motion of Tectonic Blocks in East Asia: Evidence from GPS Measurement

    2003-01-01

    The relative Euler vectors of the Pacific, Philippine, Amurian, Okhotsk, N. Honshu and South China plates or blocks are deduced from earthquake slip vectors, transform fault azimuths and spreading rates, which are consistent with new results derived from the International Terrestrial Reference Frame ITRF2000 velocity field, the velocity field of GPS stations in China and the GPS measurement data of the GEONET network in Japan. Based on the two groups of Euler vectors, analysis and comparative study of the relative motions and deformations of the tectonic blocks in East Asia reveal the present-day motion characteristics of the blocks.

  1. Knee MRI scan

    MRI - knee ... radiologist see certain areas more clearly. During the MRI, the person who operates the machine will watch ... less anxious. Your provider may suggest an "open" MRI, in which the machine is not as close ...

  2. Partial knee replacement

    ... al. American Academy of Orthopaedic Surgeons. Treatment of osteoarthritis of the knee (nonarthroplasty). J Am Acad ... Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, ...

  3. Runners knee (image)

    ... forces on the knee, such as a misaligned patella. Chondromalacia is treated with rest or immobilization and nonsteroidal anti-inflammatory drugs for pain. Physical therapy, especially ... alignment of the patella that cannot be corrected with therapy.

  4. Effects of 24-week Tai Chi exercise on the knee and ankle proprioception of older women.

    Chang, Shuwan; Zhou, Jihe; Hong, Youlian; Sun, Wei; Cong, Yan; Qin, Meiqin; Lian, Jianhua; Yao, Jian; Li, Weiping

    2016-01-01

    This study examined the effects of regular Tai Chi (TC) exercise on the kinaesthesia of the knee and ankle joints of older women. A total of 43 women aged 55-68 years participated in this study. In a 24-week study period, the TC group (n = 22) underwent an organized TC exercise, whereas the control group (n = 21) maintained a sedentary lifestyle. Customized instruments were used to measure the threshold for the detection of the passive motion of the knee and ankle joints. After 24 weeks, the TC group showed a significantly smaller threshold for the detection of passive motion of knee extension (31.4%, p = 0.009), knee flexion (27.0%, p = 0.044), and ankle dorsal flexion (28.9%, p = 0.014) than the control group. Other comparisons showed no significant differences. The 24-week TC exercise benefited the lower-limb kinaesthesia of the knee joint flexion and extension and ankle dorsal flexion.

  5. Knee Pain during Strength Training Shortly following Fast-Track Total Knee Arthroplasty

    Bandholm, Thomas; Thorborg, Kristian; Lunn, Troels Haxholdt

    2014-01-01

    BACKGROUND: Loading and contraction failure (muscular exhaustion) are strength training variables known to influence neural activation of the exercising muscle in healthy subjects, which may help reduce neural inhibition of the quadriceps muscle following total knee arthroplasty (TKA......). It is unknown how these exercise variables influence knee pain after TKA. OBJECTIVE: To investigate the effect of loading and contraction failure on knee pain during strength training, shortly following TKA. DESIGN: Cross-sectional study. SETTING: Consecutive sample of patients from the Copenhagen area, Denmark......), and ended with 1 single set to contraction failure (14 RM load). The individual loadings (kilograms) were determined during a familiarization session >72 hours prior. The patients rated their knee pain during each repetition, using a numerical rating scale (0-10). RESULTS: Two patients were lost to follow...

  6. Elastic Knee Sleeves Limit Anterior Tibial Translation in Healthy Females

    Robert Csapo, Simona Hosp, Ramona Folie, Robert Eberle, Michael Hasler, Werner Nachbauer

    2016-03-01

    Full Text Available Knee sleeves or braces represent auxiliary tools that have repeatedly been used by athletes, in an attempt to increase knee stability and, thus, reduce the risk of (recurrent ligamentous injuries. Since ACL injuries typically occur in situations involving either torsion or hyperextension of the knee, it has been speculated that braces might protect the ACL by countering excessive anterior translation of the tibia with respect to the femur (Beynnon et al., 1997. However, the preponderance of in vivo studies to test this hypothesis was performed in cohorts of patients suffering from existent ligamentous (Branch et al., 1988; Colville et al., 1986 or other knee injury (Beynnon et al., 1997; Fleming et al., 2000. This complicates the extrapolation of results to healthy subjects. Further, the braces used in these studies were mostly rigid constructs that consisted of either uni- or bilateral hinged bars (Rishiraj et al., 2009. Such braces might hinder performance (Veldhuizen et al., 1991 and would be rejected by the vast majority of healthy athletes. For these reasons, we would like to use this letter to the editor to report the results of our experiments investigating whether a relatively light elastic knee sleeve would limit the degree of anterior tibial translation in computerized arthrometry tests as performed in a sample of non-injured subjects. We recruited ten female college students (age: 23.4 ± 3.2 yrs, height: 1.68 ± 0.05 m, mass: 59.9 ± 5.5 kg who were free of acute or previous injury or any form of orthopaedic disease of the knee joints. The anterior displacement of the tibia was measured using the GNRB® computerized arthrometer (GeNouRob, Laval, France. With subjects lying in the supine position, the lower leg was firmly fixed with plastic caps mounted over the ankle joint and patella. An electrical pressure pad then exerted increasing pressure of up to 250 N on the calf, while a motion sensor, which was positioned on the ventral

  7. Tribology studies of the natural knee using an animal model in a new whole joint natural knee simulator.

    Liu, Aiqin; Jennings, Louise M; Ingham, Eileen; Fisher, John

    2015-09-18

    The successful development of early-stage cartilage and meniscus repair interventions in the knee requires biomechanical and biotribological understanding of the design of the therapeutic interventions and their tribological function in the natural joint. The aim of this study was to develop and validate a porcine knee model using a whole joint knee simulator for investigation of the tribological function and biomechanical properties of the natural knee, which could then be used to pre-clinically assess the tribological performance of cartilage and meniscal repair interventions prior to in vivo studies. The tribological performance of standard artificial bearings in terms of anterior-posterior (A/P) shear force was determined in a newly developed six degrees of freedom tribological joint simulator. The porcine knee model was then developed and the tribological properties in terms of shear force measurements were determined for the first time for three levels of biomechanical constraints including A/P constrained, spring force semi-constrained and A/P unconstrained conditions. The shear force measurements showed higher values under the A/P constrained condition (predominantly sliding motion) compared to the A/P unconstrained condition (predominantly rolling motion). This indicated that the shear force simulation model was able to differentiate between tribological behaviours when the femoral and tibial bearing was constrained to slide or/and roll. Therefore, this porcine knee model showed the potential capability to investigate the effect of knee structural, biomechanical and kinematic changes, as well as different cartilage substitution therapies on the tribological function of natural knee joints.

  8. Taking care of your new knee joint

    Knee arthroplasty - precautions; Knee replacement - precautions ... After you have knee replacement surgery , you will need to be careful about how you move your knee, especially for the first few ...

  9. Effect of knee joint angle on side-to-side strength ratios.

    Krishnan, Chandramouli; Williams, Glenn N

    2014-10-01

    Isometric knee extensor and flexor strength are typically tested at different joint angles due to the differences in length-tension relationships of the quadriceps and hamstring muscles. The efficiency of strength testing can be improved if the same angle can be used to test both the knee extensor and flexor muscle groups. The aim of this study was to determine an optimal angle for isometric knee strength testing by examining the effect of knee angle on side-to-side peak torque ratios. Eighteen active young people (9 males and 9 females) participated in this study. Knee extensor and knee flexor strength were tested on both sides at 30°, 60°, and 90° of knee flexion. The effect of knee flexion angle on side-to-side peak torque ratios, raw torque values, and side-to-side flexor-to-extensor torque ratios were assessed. Side-to-side knee extensor peak torque ratios and knee flexor-to-extensor torque ratios differed significantly by knee flexion angle (p = 0.024 and p = 0.011, respectively), but side-to-side knee flexor peak torque ratios did not differ significantly (p = 0.311). When considering both side-to-side peak torque ratios and flexor-to-extensor torque ratios, the values were more symmetrical (i.e., closer to 100%) only at 60° of knee flexion. Our results indicate that both the knee flexors and the knee extensors can be tested clinically at 60° of knee flexion. Our results also indicate that the hamstrings can be tested at any of the 3 angles if the examiner is interested in side-to-side ratios rather than raw torque values. These results may facilitate more efficient and flexible clinical knee strength testing.

  10. Application of a novel spinal posture and motion measurement system in active and static sitting.

    Pries, Esther; Dreischarf, Marcel; Bashkuev, Maxim; Schmidt, Hendrik

    2015-01-01

    The quantification of work-related musculoskeletal risk factors is of great importance; however, only a few tools allow objective, unrestricted measurements of spinal posture and motion in workplaces. This study was performed to evaluate the applicability of the Epionics system in a sedentary workplace. The system is mobile and wireless and assesses lumbar lordosis, pelvic orientation and spinal motion, without restricting subjects in their movements. In total, 10 males were monitored while sitting for 2 h on static and dynamic office chairs and on an exercise ball, to evaluate the effect of dynamic sitting. The volunteers were able to perform their work unhampered. No differences among the tested furniture could be detected with respect to either the lordosis or the number of spinal movements after habituation to the furniture; however, differences in pelvic orientation were statistically significant. The results of the present study indicate that Epionics may be useful for the quantitative assessment of work-related risk factors. Practitioner Summary: Only a few tools allow objective, unrestricted measurements of spinal posture and motion in the workplace. Epionics SPINE measures lumbar lordosis, pelvic orientation and spinal motion under nearly unrestricted conditions and can be used to quantify work-related musculoskeletal risk factors. We demonstrated the use of this tool in the workplace-analysis.

  11. Standard versus high-flexion posterior stabilized total knee prostheses.

    Li, Ning; Li, Junwei; Li, Peng; Wang, Dan; Liu, Ming; Xia, Lei

    2015-03-01

    This meta-analysis compared clinical outcomes between standard and high-flexion posterior-stabilized total knee prostheses to evaluate which type of total knee prosthesis was superior. Randomized, controlled trials published until October 2013 comparing standard and high-flexion posterior-stabilized total knee prostheses were reviewed. Methodologic quality was assessed with the Physiotherapy Evidence Database scale. After data extraction, the authors compared results with fixed effects or random effects models, depending on the heterogeneity of the included studies. Eight randomized, controlled trials involving 660 patients met the predetermined inclusion criteria. No statistically significant differences between patients undergoing standard and high-flexion posterior-stabilized total knee prostheses were noted in postoperative range of motion (ROM) (weighted mean difference, -1.43; 95% confidence interval [CI], -4.52 to 1.67; P=.37); flexion angle (weighted mean difference, 0.54; 95% CI, -3.75 to 4.84; P=.80); Knee Society Score (weighted mean difference, 0.92; 95% CI, -0.64 to 2.48; P=.25); Hospital for Special Surgery knee score (weighted mean difference, 0.57; 95% CI, -0.42 to 1.55; P=.26); or Knee Society function score (weighted mean difference, 1.00; 95% CI, -1.49 to 3.49; P=.43). No statistical difference was found between the 2 prosthesis types in complications, involving 21 cases in the standard group and 14 cases in the high-flexion group. The current findings confirm that high-flexion posterior-stabilized total knee prostheses are not superior to standard prostheses in terms of ROM, flexion angle, knee scores, or complications with 5 years or less of follow-up.

  12. Does post-operative knee awareness differ between knees in bilateral simultaneous total knee arthroplasty?

    Nielsen, Katrine Abildgaard; Thomsen, Morten Grove; Latifi Yaghin, Roshan;

    2016-01-01

    PURPOSE: To evaluate the difference in post-operative knee awareness between knees in patients undergoing bilateral simultaneous total knee arthroplasty (TKA) and to assess factors predicting high or low knee awareness. METHODS: This study was conducted on 99 bilateral simultaneous TKAs performed...... at our institution from 2008 to 2012. All patients received one set of questionnaires [Forgotten Joint Score (FJS) and Oxford Knee Score (OKS)] for each knee. Based on the FJS, the patients' knees were divided into two groups: "best" and "worst" knees. The median of the absolute difference in FJS and OKS...... within each patient was calculated. Multivariate linear regression was performed to identify factors affecting FJS. RESULTS: The difference between knees was 1 point (CI 0-5) for the FJS and 1 point (CI 0-2) for the OKS. The FJS for females increased (decreasing awareness) with increasing age. Males had...

  13. Three-dimensional knee kinematics by conventional gait analysis for eleven motor tasks of daily living: typical patterns and repeatability.

    Scheys, Lennart; Leardini, Alberto; Wong, Pius D; Van Camp, Laurent; Callewaert, Barbara; Bellemans, Johan; Desloovere, Kaat

    2013-04-01

    The availability of detailed knee kinematic data during various activities can facilitate clinical studies of this joint. To describe in detail normal knee joint rotations in all three anatomical planes, 25 healthy subjects (aged 22-49 years) performed eleven motor tasks, including walking, step ascent and descent, each with and without sidestep or crossover turns, chair rise, mild and deep squats, and forward lunge. Kinematic data were obtained with a conventional lower-body gait analysis protocol over three trials per task. To assess the repeatability with standard indices, a representative subset of 10 subjects underwent three repetitions of the entire motion capture session. Extracted parameters with good repeatability included maximum and minimum axial rotation during turning, local extremes of the flexion curves during gait tasks, and stride times. These specific repeatable parameters can be used for task selection or power analysis when planning future clinical studies.

  14. EFFICACY OF KINESIO-TAPING VERSUS PHONOPHORESIS ON KNEE OSTEOARTHRITIS: AN EXPERIMENTAL STUDY

    Magda Gaid Sedhom

    2016-08-01

    Full Text Available Background: Osteoarthritis (OA is the most common type of joint disease. Pain is the most common symptom of knee osteoarthritis. Also it characterized by sign, symptoms of inflammation, pain, stiffness and loss of mobility. This study was conducted to explore the efficacy of kinesio taping (KT versus Aescin, Diethylamine Salicylate gel phonophoresis (PH on pain level, range of motion (ROM, and proprioceptive accuracy on mild to moderate knee OA patients. Methods: Forty females with knee OA from Outpatient Clinic of Physical Therapy Faculty participated in the study with mean age (49±5.82 years. They were randomly assigned into 2 equal groups. Group I: received Aescin, Diethylamine Salicylate gel PH with pulsed ultrasound therapy and group II received KT. All patients received hot packs and selected exercise program for four weeks; three sessions per week. Visual analogue scale was used in assessment of pain level. Electronic digital goniometer was used in assessment of knee flexion ROM. Iso-kinetic daynamometer was used in assessment of knee proprioceptive accuracy. Results: There was a significant relieving of pain perception, increasing of knee flexion ROM and improving proprioceptive accuracy in knee joint post-study in both groups. But application of Aescin, Diethylamine Salicylate gel PH had significant relieve of knee pain than KT. Conclusion: Using of Aescin, Diethylamine Salicylate gel PH is more effective than KT application in reliving knee pain in knee osteoarthritic patients.

  15. Are both the knees of the same size? Analysis of component asymmetry in 289 bilateral knee arthroplasties

    Venkata Gurava Reddy

    2011-01-01

    Full Text Available Background: Variations in the anatomy of knee are well described, however the true incidence of component asymmetry in bilateral total knee arthroplsties is rarely reported. Incidence of component asymmetry in bilateral total knee arthroplasties (TKA was retrospectively analysed in 289 cruciate retaining total knee arthroplasties. Materials and Methods: Medical records of these 289 patients were evaluated for the incidence of asymmetry of either femoral or tibial components. Clinical outcomes were compared between the cases of asymetrical components to that of symmetrical components. Results: Incidence of femoral component asymmetry was found to be 9.2% and tibial component asymmetry to be 8.7%. Of 289 cases, TKA 178 were done in a single day (group A, while 111 were done at 2- to 3-day intervals (group B. Asymmetric and symmetric knees were equally distributed among both groups, male and female patients in both groups, and the incidence of component asymmetry was similar between all four different implants - Optetrak-CR (Exactech, Gainesville, FL, USA, Nexgen-CR (Zimmer, Warsaw, IN, USA, PFC-Sigma CR (DePuy, Warsaw, IN, USA, Genesis II CR (Smith and Nephew, Memphis, TN, USA we used. The pre- and postoperative range of motion and pre- and postoperative knee society scores were compared between the symmetric and asymmetric cases in both the groups and the difference was found to be insignificant. Conclusion: We conclude that incidence of component asymmetry in bilateral total knee arthroplasty is around 9 % and independent sizing of both knees during bilateral arthoplasty is recommended rather than simply relying on the contralateral knee measurements.

  16. Design and Evaluation of a New Type of Knee Orthosis to Align the Mediolateral Angle of the Knee Joint with Osteoarthritis

    Amir Esrafilian

    2012-01-01

    Full Text Available Background. Osteoarthritis (OA is a disease which influences the performance of the knee joint. Moreover, the force and moments applied on the joint increase in contrast to normal subjects. Various types of knee orthoses have been designed to solve the mentioned problems. However, there are other problems in terms of distal migration during walking and the alignment of the orthosis which cannot be changed following the use of brace. Therefore, the main aim of the research was to design an orthosis to solve the aforementioned problems. Method. A new type of knee orthosis was designed with a modular structure. Two patients with knee OA participated in this research project. The force applied on the foot, moment transmitted through the knee joint, and spatiotemporal gait parameters were measured by use of a motion analysis system. Results. The results of the research showed that the adduction moment applied on the knee joint decreased while subjects walked with the new knee orthosis (P-value < 0.05. Conclusion. The new design of the knee brace can be used as an effective treatment to decrease the loads applied on the knee joint and to improve the alignment whilst walking.

  17. Design and evaluation of a new type of knee orthosis to align the mediolateral angle of the knee joint with osteoarthritis.

    Esrafilian, Amir; Karimi, Mohammad Taghi; Eshraghi, Arezoo

    2012-01-01

    Background. Osteoarthritis (OA) is a disease which influences the performance of the knee joint. Moreover, the force and moments applied on the joint increase in contrast to normal subjects. Various types of knee orthoses have been designed to solve the mentioned problems. However, there are other problems in terms of distal migration during walking and the alignment of the orthosis which cannot be changed following the use of brace. Therefore, the main aim of the research was to design an orthosis to solve the aforementioned problems. Method. A new type of knee orthosis was designed with a modular structure. Two patients with knee OA participated in this research project. The force applied on the foot, moment transmitted through the knee joint, and spatiotemporal gait parameters were measured by use of a motion analysis system. Results. The results of the research showed that the adduction moment applied on the knee joint decreased while subjects walked with the new knee orthosis (P-value knee brace can be used as an effective treatment to decrease the loads applied on the knee joint and to improve the alignment whilst walking.

  18. Implant fixation of tibial avulsion fracture of the posterior cruciate ligament:knee joint range of motion and functional evaluation%植入物固定后交叉韧带胫骨止点撕脱骨折:膝关节活动度及功能评价

    王良勇; 李建刚; 张春; 张俊; 杜红军; 崔操; 田大为

    2015-01-01

    BACKGROUND:From the biological structure, the posterior cruciate ligament is surrounded by the synovial folds of posterior capsule, arising from the inner side of the medial femoral condyle to the posterior part of tibial intercondyloid spine. The main traditional treatment method for posterior cruciate ligament tibial avulsion fracture is open operation, but it is difficult in anatomic reduction, cannot ful y restore knee joint stability and has a great negative impact on the normal function of posterior cruciate ligament. OBJECTIVE:To investigate the effects of arthroscopic implant internal fixation in the treatment of tibial avulsion fracture of the posterior cruciate ligament. METHODS:120 patients with tibial avulsion fracture of the posterior cruciate ligament were randomly assigned into treatment group and control group, with 60 cases in each group. The control group was given the traditional open surgery, and the treatment group was given the arthroscopic surgery. After 3 months, International Knee Documentation Committee (IKDC) scores and Lysholm scores were detected in the two groups;the knee joint range of motion was determined before and 3 months after treatment. RESULTS AND CONCLUSION:Wounds were healed at stage I in al patients with no serious complications. There was no difference in the knee joint range of motion between the two groups before treatment, but the range of motion was increased significantly in both two groups at 3 months after treatment (P<0.05), meanwhile which was higher in the treatment group than the control group (P<0.05). At 3 months after treatment, the excel ent knee function rate was significantly higher in the treatment group (97%) than the control group (88%) according to the Lysholm scores;the IKDC scores were significantly higher in the treatment than the control group in terms of claudication, support, pain, swel ing, and squat (P<0.05). These results indicate that the arthroscopic implant fixation of tibial avulsion

  19. [Jumper's knee--a review].

    Tibesku, C O; Pässler, H H

    2005-06-01

    Jumper's knee has been defined as painful chronic overuse injury of the extensor mechanism of the knee joint. The disease has a high incidence in jumping sports and depends on training frequency and level of performance. Its natural course is protracted, repetitive, and often bilaterally occurring. Its etiology is a chronic overload of the knee extensor mechanism which is triggered by jumping sports (volleyball, basketball etc.) as well as different intrinsic (ligamentous laxity, Q-angle, patella height, tenderness, pattern of force development) and extrinsic dispositions (frequency of training, level of performance, hardness of underground). The place of pathology most often is the osteo-tendinous transition zone of the proximal patellar tendon. Histologic evaluation of the tendon showed that the disease is rather degenerative than inflammatory. The diagnosis is primarily based on the typical sports history, physical examination, and ultrasound. MRI is helpful in operation planning. Plain radiography, CT, and bone scans are used to rule out differential diagnoses. Therapy should be chosen according to the stage of the disease and usually starts with a non-surgical approach. This includes rest from sports activities, immobilisation, non-steroid antiphlogistics, para-tendinous cortisone injections, massage, electric therapy, ultrasound and extracorporal shock waves. Afterwards an increase of activities is begun (moderate training, adequate warm-up, ice cooling after activity, muscle stretching, eccentric strengthening of the quadriceps). Patella straps and soft insoles are used as prevention. Up to 42 % of patients need surgical therapy after failure of long-lasting non-surgical measures, carried out either open or arthroscopically. Surgical principles include excision of the para-tendon, excision of the degenerative tissue, resection of the lower patella pole, and longitudinal incisions into the tendon. Most patients are pain-free after surgery but return to sports

  20. The relationship between the active cervical range of motion and changes in head and neck posture after continuous VDT work.

    Yoo, Won-Gyu; An, Duk-Hyun

    2009-04-01

    This study investigated the relationship between the active cervical range of motion (ROM) and changes in the head and neck posture after continuous visual display terminal (VDT) work. Twenty VDT workers were recruited from laboratories. The active cervical ROM of the participants was measured and videotaped to capture the craniocervical and cervicothoracic angles using a single video camera before and after VDT work. Pearson correlation coefficients were used to quantify the linear relationship between active cervical ROM measurements and the changes in the craniocervical and cervicothoracic angles after continuous VDT work. Active neck extension (r=-0.84, p<0.01) was negatively correlated with the mean craniocervical angle, and active neck flexion (r=-0.82, p<0.01) and left lateral flexion (r=-0.67, p<0.01) were negatively correlated with the mean cervicothoracic angle.

  1. Avoidance of activity and disability in patients with osteoarthritis of the knee: the mediating role of muscle strength.

    Steultjens, M.P.M.; Dekker, J.; Bijlsma, J.W.J.

    2002-01-01

    OBJECTIVE: Avoidance of activity is hypothesized to lead to muscle weakness and consequently, to physical disability. This study was undertaken to validate the avoidance model by providing evidence for the mediating role of muscle weakness in the relationship between avoidance of activity and physic

  2. Avoidance of activity and disability in patients with osteoarthritis of the knee - The mediating role of muscle strength

    Steultjens, MPM; Dekker, J; Bijlsma, JWJ

    2002-01-01

    Objective. Avoidance of activity is hypothesized to lead to muscle weakness and consequently, to physical disability. This study was undertaken to validate the avoidance model by providing evidence for the mediating role of muscle weakness in the relationship between avoidance of activity and physic

  3. Quantitative analysis of the reversibility of knee flexion contractures with time: an experimental study using the rat model

    Trudel, Guy; Uhthoff, Hans K.; Goudreau, Louis; Laneuville, Odette

    2014-01-01

    Background Knee flexion contractures prevent the full extension of the knee joint and cause disability. The etiology is not well defined. Extended periods of immobilization of joints lead to contractures difficult to completely reverse by rehabilitation treatments. Recovery of the complete range of motion without intervention has not been studied but is of importance to optimize clinical management. This study was designed to quantify the spontaneous reversibility of knee flexion contractures...

  4. Effect of antagonist muscle fatigue on knee extension torque.

    Beltman, J G M; Sargeant, A J; Ball, D; Maganaris, C N; de Haan, A

    2003-09-01

    The effect of hamstring fatigue on knee extension torque was examined at different knee angles for seven male subjects. Before and after a dynamic flexion fatigue protocol (180 degrees s(-1), until dynamic torque had declined by 50%), maximal voluntary contraction extension torque was measured at four knee flexion angles (90 degrees, 70 degrees, 50 degrees and 30 degrees ). Maximal torque generating capacity and voluntary activation of the quadriceps muscle were determined using electrical stimulation. Average rectified EMG of the biceps femoris was determined. Mean dynamic flexion torque declined by 48+/-11%. Extensor maximal voluntary contraction torque, maximal torque generating capacity, voluntary activation and average rectified EMG at the four knee angles were unaffected by the hamstring fatigue protocol. Only at 50 degrees knee angle was voluntary activation significantly lower (15.7%) after fatigue ( P<0.05). In addition, average rectified EMG before fatigue was not significantly influenced by knee angle. It was concluded that a fatigued hamstring muscle did not increase the maximal voluntary contraction extension torque and knee angle did not change coactivation. Three possible mechanisms may explain the results: a potential difference in recruited fibre populations in antagonist activity compared with the fibres which were fatigued in the protocol, a smaller loss in isometric torque generating capacity of the hamstring muscle than was expected from the dynamic measurements and/or a reduction in voluntary activation.

  5. Three statistical experimental designs for enhancing yield of active compounds from herbal medicines and anti motion sickness bioactivity

    Yan Chen

    2015-01-01

    Full Text Available Background: Since antiquity, Zingiber officinale (ginger, pogostemonis herba, and radix aucklandiae have been used as traditional Chinese medicines to remit gastrointestinal discomfort. Recent evidences also show the efficacy of the three herbal medicines against nausea and vomiting. Objective: To optimize the CO2 supercritical fluid extraction (SFE CO2 conditions for ginger and the ethanol reflux extraction conditions for radix aucklandiae, control the quality of pogostemonis herba essential oil, and evaluate anti motion sickness activity of the compound recipes composed of the three herbal medicine extracts. Materials and Methods: Two orthogonal array designs L9 (34 were employed to optimize the SFE CO2 conditions for enhancing yield of 6 gingerol from ginger and the ethanol reflux extraction conditions for enhancing yield of costunolide and dehydrocostus lactone from radix aucklandiae; a uniform design U5(53 was applied for evaluation of anti motion sickness activity of the compound recipes. Results: Extraction pressure (P < 0.01, extraction temperature and extraction time (P < 0.05 have significant effects on the yield of 6 gingerol from ginger by SFE CO2; ethanol concentration (P < 0.01 and times of repeating extraction (P < 0.05 have significant effects on the total yield of costunolide and dehydrocostus lactone from radix aucklandiae by ethanol reflux extraction; the anti motion sickness effects of the optimized compound recipe composed of the three herbal medicine extracts were markedly better than those of dimenhydrinate. Conclusion: The compound recipe composed of ginger, pogostemonis herba, and radix aucklandiae could be developed as a promising anti motion sickness medicine.

  6. The spectral analysis of motion: An "open field" activity test example

    Obradović Z.

    2013-01-01

    Full Text Available In this work we have described the new mathematical approach, with spectral analysis of the data to evaluate position and motion in the „„open field““ experiments. The aim of this work is to introduce several new parameters mathematically derived from experimental data by means of spectral analysis, and to quantitatively estimate the quality of the motion. Two original software packages (TRACKER and POSTPROC were used for transforming a video data to a log file, suitable for further computational analysis, and to perform analysis from the log file. As an example, results obtained from the experiments with Wistar rats in the „open field“ test are included. The test group of animals was treated with diazepam. Our results demonstrate that all the calculated parameters, such as movement variability, acceleration and deceleration, were significantly lower in the test group compared to the control group. We believe that the application of parameters obtained by spectral analysis could be of great significance in assessing the locomotion impairment in any kind of motion. [Projekat Ministarstva nauke Republike Srbije, br. III41007 i br. ON174028

  7. Biomechanical risk factors and mechanisms of knee injury in golfers.

    Marshall, Robert N; McNair, Peter J

    2013-09-01

    Knee injuries in golf comprise approximately 8% of all injuries, and are considered to result from overuse, technical faults or a combination of those factors. This review examines factors involved in injury, including the structure of the knee joint, kinematics and kinetics of the golf swing, forces sustained by knee joint structures and the potential for joint injury as well as injury prevention strategies. The golf swing generates forces and torques which tend to cause internal or external rotation of the tibia on the femur, and these are resisted by the knee ligaments and menisci. Research has shown that both maximum muscle forces and the forces sustained during a golf swing are less than that required to cause damage to the ligaments. However, the complex motion of the golf swing, involving both substantial forces and ranges of rotational movement, demands good technique if the player is to avoid injuring their knee joint. Most knee injury in golf is likely related to joint laxity, previous injuries or arthritis, and such damage may be exacerbated by problems in technique or overuse. In addition to appropriate coaching, strategies to remedy discomfort include specific exercise programmes, external bracing, orthotics and equipment choices.

  8. Prevalent knee pain and sport

    Hahn, Thomas; Foldspang, Anders

    1998-01-01

    and with weekly hours of participation in competitive gymnastics but negatively with weekly hours of tennis. Constant or recurrent knee pain was positively associated with years of swimming. Absence from sport due to knee pain was positively associated with weekly hours of soccer participation. CONCLUSIONS: Knee...

  9. Exoskeleton Motion Control for Children Walking Rehabilitation

    Cristina Ploscaru

    2016-06-01

    Full Text Available This paper introduces a quick method for motion control of an exoskeleton used on children walking rehabilitation with ages between four to seven years old. The exoskeleton used on this purpose has six servomotors which work independently and actuates each human lower limb joints (hips, knees and ankles. For obtaining the desired motion laws, a high-speed motion analysis equipment was used. The experimental rough data were mathematically modeled in order to obtain the proper motion equations for controlling the exoskeleton servomotors.

  10. Using motion-sensor camera technology to infer seasonal activity and thermal niche of the desert tortoise (Gopherus agassizii).

    Agha, Mickey; Augustine, Benjamin; Lovich, Jeffrey E; Delaney, David; Sinervo, Barry; Murphy, Mason O; Ennen, Joshua R; Briggs, Jessica R; Cooper, Robert; Price, Steven J

    2015-01-01

    Understanding the relationships between environmental variables and wildlife activity is an important part of effective management. The desert tortoise (Gopherus agassizii), an imperiled species of arid environments in the southwest US, may have increasingly restricted windows for activity due to current warming trends. In summer 2013, we deployed 48 motion sensor cameras at the entrances of tortoise burrows to investigate the effects of temperature, sex, and day of the year on the activity of desert tortoises. Using generalized estimating equations, we found that the relative probability of activity was associated with temperature (linear and quadratic), sex, and day of the year. Sex effects showed that male tortoises are generally more active than female tortoises. Temperature had a quadratic effect, indicating that tortoise activity was heightened at a range of temperatures. In addition, we found significant support for interactions between sex and day of the year, and sex and temperature as predictors of the probability of activity. Using our models, we were able to estimate air temperatures and times (days and hours) that were associated with maximum activity during the study. Because tortoise activity is constrained by environmental conditions such as temperature, it is increasingly vital to conduct studies on how tortoises vary their activity throughout the Sonoran Desert to better understand the effects of a changing climate.

  11. Using motion-sensor camera technology to infer seasonal activity and thermal niche of the desert tortoise (Gopherus agassizii)

    Agha, Mickey; Augustine, Benjamin; Lovich, Jeffrey E.; Delaney, David F.; Sinervo, Barry; Murphy, Mason O.; Ennen, Joshua R.; Briggs, Jessica R.; Cooper, Robert J.; Price, Steven J.

    2015-01-01

    Understanding the relationships between environmental variables and wildlife activity is an important part of effective management. The desert tortoise (Gopherus agassizii), an imperiled species of arid environments in the southwest US, may have increasingly restricted windows for activity due to current warming trends. In summer 2013, we deployed 48 motion sensor cameras at the entrances of tortoise burrows to investigate the effects of temperature, sex, and day of the year on the activity of desert tortoises. Using generalized estimating equations, we found that the relative probability of activity was associated with temperature (linear and quadratic), sex, and day of the year. Sex effects showed that male tortoises are generally more active than female tortoises. Temperature had a quadratic effect, indicating that tortoise activity was heightened at a range of temperatures. In addition, we found significant support for interactions between sex and day of the year, and sex and temperature as predictors of the probability of activity. Using our models, we were able to estimate air temperatures and times (days and hours) that were associated with maximum activity during the study. Because tortoise activity is constrained by environmental conditions such as temperature, it is increasingly vital to conduct studies on how tortoises vary their activity throughout the Sonoran Desert to better understand the effects of a changing climate.

  12. Active motion of a Janus particle by self-thermophoresis in a defocused laser beam.

    Jiang, Hong-Ren; Yoshinaga, Natsuhiko; Sano, Masaki

    2010-12-31

    We study self-propulsion of a half-metal coated colloidal particle under laser irradiation. The motion is caused by self-thermophoresis: i.e., absorption of a laser at the metal-coated side of the particle creates local temperature gradient which in turn drives the particle by thermophoresis. To clarify the mechanism, temperature distribution and a thermal slip flow field around a microscale Janus particle are measured for the first time. With measured temperature drop across the particle, the speed of self-propulsion is corroborated with the prediction based on accessible parameters. As an application for driving a micromachine, a microrotor is demonstrated.

  13. A purpose-built dynamometer to objectively measure static and dynamic knee torque.

    Ugbolue, U C; Kaliarntas, K T; Wearing, S C; Rowe, P J

    2011-05-01

    This paper reports the development of a purpose-built knee dynamometer (PBKD) to evaluate passive range of motion (ROM) and isometric muscle strength measurements of the knee. The PBKD uses a TorqSense rotary torque transducer and objectively measures isometric knee muscle strength in a valid and reliable manner and passive resistance to motion through range. The device and all associated instrumentation underwent dynamic and static calibration to ensure consistent and accurate measurements were obtained in terms of knee joint angular position, passive torque measures, and isometric torque measures. Eleven healthy male participants performed a knee flexion and extension task designed to evaluate knee function. The validation of the PBKD entailed measuring the consistency of measurement and accuracy of measurement. Accuracy of the PBKD was determined by comparing peak isometric muscle strength measurements against a KIN-COM machine. No significant differences were observed both passively and isometrically between cycles and between trials. This device can have widespread applications within the rehabilitation and clinical environment and could be used as a functional outcome measuring tool to distinguish pathological from non-pathological knees. The presented preliminary results indicate that reliable and accurate measurements of knee ROM and muscle strength can be obtained.

  14. The influence of knee marker placement error on evaluation of gait kinematic parameters.

    Szczerbik, Ewa; Kalinowska, Małgorzata

    2011-01-01

    Vicon motion system is an accurate equipment for objective gait analysis. According to clinical experience the most important source of errors in kinematics is marker misplacement. It seems that knee marker placement is especially important because of its direct influence on two body segments: thigh and shank. There is little data in the literature on how the misplacement of knee marker determines the changes of kinematic parameters. Therefore the aim of this study was to collect the kinematic data of subjects with different knee pathologies (one with knee flexion contracture, the second with knee hyperextension) while knee marker position was changed in a systematical way. They were walking with their natural, preferred speed. The data were collected using VICON460 motion system, the Helen Hayes marker set and Plug-In-Gait model. Then they were processed based on Polygon software. The results of both subjects showed the changes of kinematics, depending on the knee marker misplacement. The assessed joint ranges of angle change were: in knee, 18° in sagittal plane and 20° in frontal plane; in hip, 10° in sagittal plane and 24° in transversal plane; in ankle, 10° in sagittal plane and 25° in transversal plane. This paper presents the detailed data which could help the users of such systems to interpret the kinematic data.

  15. Effect of Preactivation on Torque Enhancement by the Stretch-Shortening Cycle in Knee Extensors.

    Fukutani, Atsuki; Misaki, Jun; Isaka, Tadao

    2016-01-01

    The stretch-shortening cycle is one of the most interesting topics in the field of sport sciences, because the performance of human movement is enhanced by the stretch-shortening cycle (eccentric contraction). The purpose of the present study was to examine whether the influence of preactivation on the torque enhancement by stretch-shortening cycle in knee extensors. Twelve men participated in this study. The following three conditions were conducted for knee extensors: (1) concentric contraction without preactivation (CON), (2) concentric contraction with eccentric preactivation (ECC), and (3) concentric contraction with isometric preactivation (ISO). Muscle contractions were evoked by electrical stimulation to discard the influence of neural activity. The range of motion of the knee joint was set from 80 to 140 degrees (full extension = 180 degrees). Angular velocities of the concentric and eccentric contractions were set at 180 and 90 degrees/s, respectively. In the concentric contraction phase, joint torques were recorded at 85, 95, and 105 degrees, and they were compared among the three conditions. In the early phase (85 degrees) of concentric contraction, the joint torque was larger in the ECC and ISO conditions than in the CON condition. However, these clear differences disappeared in the later phase (105 degrees) of concentric contraction. The results showed that joint torque was clearly different among the three conditions in the early phase whereas this difference disappeared in the later phase. Thus, preactivation, which is prominent in the early phase of contractions, plays an important role in torque enhancement by the stretch-shortening cycle in knee extensors.

  16. Effect of Preactivation on Torque Enhancement by the Stretch-Shortening Cycle in Knee Extensors.

    Atsuki Fukutani

    Full Text Available The stretch-shortening cycle is one of the most interesting topics in the field of sport sciences, because the performance of human movement is enhanced by the stretch-shortening cycle (eccentric contraction. The purpose of the present study was to examine whether the influence of preactivation on the torque enhancement by stretch-shortening cycle in knee extensors. Twelve men participated in this study. The following three conditions were conducted for knee extensors: (1 concentric contraction without preactivation (CON, (2 concentric contraction with eccentric preactivation (ECC, and (3 concentric contraction with isometric preactivation (ISO. Muscle contractions were evoked by electrical stimulation to discard the influence of neural activity. The range of motion of the knee joint was set from 80 to 140 degrees (full extension = 180 degrees. Angular velocities of the concentric and eccentric contractions were set at 180 and 90 degrees/s, respectively. In the concentric contraction phase, joint torques were recorded at 85, 95, and 105 degrees, and they were compared among the three conditions. In the early phase (85 degrees of concentric contraction, the joint torque was larger in the ECC and ISO conditions than in the CON condition. However, these clear differences disappeared in the later phase (105 degrees of concentric contraction. The results showed that joint torque was clearly different among the three conditions in the early phase whereas this difference disappeared in the later phase. Thus, preactivation, which is prominent in the early phase of contractions, plays an important role in torque enhancement by the stretch-shortening cycle in knee extensors.

  17. Chondropathia patellae and knee muscle control. An electromyographic study.