Temporomandibular joint motion

International Nuclear Information System (INIS)

Maeda, M.; Kawamura, Y.; Matsuda, T.; Itou, S.; Odori, T.; Ishii, Y.; Torizuka, K.

1990-01-01

This paper evaluates MR imaging with the therapeutic effect after splint therapy in internal derangement of the temporomandibular joint (TMJ). Fifteen patients (19 TMJs) with internal derangement of the TMJ and five normal volunteers (10 TMJs) were examined with sagittal T1-weighted spin-echo and gradient recalled acquisition in a steady state (GRASS) MR imaging. MR studies of the patients undergoing splint therapy were performed with an without splints. Pseudodynamic images of TMJ motion provide information that was not available from spin-echo T1-weighted images

Passive Muscle-Tendon Unit Gearing is Joint Dependent in Human Medial Gastrocnemius

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Emma F Hodson-Tole

2016-03-01

Full Text Available Skeletal muscles change length and develop force both passively and actively. Gearing allows muscle fibre length changes to be uncoupled from those of the whole muscle-tendon unit. During active contractions this process allows muscles to operate at mechanically favorable conditions for power or economical force production. Here we ask whether gearing is constant in passive muscle; determining the relationship between fascicle and muscle-tendon unit length change in the bi-articular medial gastrocnemius and investigating the influence of whether motion occurs at the knee or ankle joint. Specifically, the same muscle-tendon unit length changes were elicited by rotating either the ankle or knee joint whilst simultaneously measuring fascicle lengths in proximal and distal muscle regions using B-mode ultrasound. In both the proximal and distal muscle region, passive gearing values differed depending on whether ankle or knee motion occurred. Fascicle length changes were greater with ankle motion, likely reflecting anatomical differences in proximal and distal passive tendinous tissues, as well as shape changes of the adjacent mono-articular soleus. This suggests that there is joint-dependent dissociation between the mechanical behaviour of muscle fibres and the muscle-tendon unit during passive joint motions that may be important to consider when developing accurate models of bi-articular muscles.

Joint motion clusters in servomanipulator operation

International Nuclear Information System (INIS)

Draper, J.V.; Sundstrom, E.; Herndon, J.N.

1986-01-01

The Consolidated Fuel Reprocessing Program (CFRP) at the Oak Ridge National Laboratory is developing advanced teleoperator systems for maintenance of future nuclear fuel reprocessing facilities. Remote maintenance systems developed by the CFRP emphasize man-in-the-loop teleoperation. This paper reports the results of a recent experiment which investigated how users interact with a multi-degree-of-freedom servomanipulator. Principal components analysis performed on data collected during completion of typical remote maintenance tests indicates that joint motions may be summarized by two orthogonal clusters, one which represents fine-adjusting motions and one which represents slewing motions. Implications of these findings for servomanipulator design are discussed. 5 refs., 1 fig., 2 tabs

Sacroiliac Joint Fusion Minimally Affects Adjacent Lumbar Segment Motion: A Finite Element Study.

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Lindsey, Derek P; Kiapour, Ali; Yerby, Scott A; Goel, Vijay K

2015-01-01

Adjacent segment disease is a recognized consequence of fusion in the spinal column. Fusion of the sacroiliac joint is an effective method of pain reduction. Although effective, the consequences of sacroiliac joint fusion and the potential for adjacent segment disease for the adjacent lumbar spinal levels is unknown. The objective of this study was to quantify the change in range of motion of the sacroiliac joint and the adjacent lumbar spinal motion segments due to sacroiliac joint fusion and compare these changes to previous literature to assess the potential for adjacent segment disease in the lumbar spine. An experimentally validated finite element model of the lumbar spine and pelvis was used to simulate a fusion of the sacroiliac joint using three laterally placed triangular implants (iFuse Implant System, SI-BONE, Inc., San Jose, CA). The range of motion of the sacroiliac joint and the adjacent lumbar spinal motion segments were calculated using a hybrid loading protocol and compared with the intact range of motion in flexion, extension, lateral bending, and axial rotation. The range of motions of the treated sacroiliac joints were reduced in flexion, extension, lateral bending, and axial rotation, by 56.6%, 59.5%, 27.8%, and 53.3%, respectively when compared with the intact condition. The stiffening of the sacroiliac joint resulted in increases at the adjacent lumbar motion segment (L5-S1) for flexion, extension, lateral bending, and axial rotation, of 3.0%, 3.7%, 1.1%, and 4.6%, respectively. Fusion of the sacroiliac joint resulted in substantial (> 50%) reductions in flexion, extension, and axial rotation of the sacroiliac joint with minimal (sacroiliac joint fusion, the long-term clinical results remain to be investigated.

4D rotational x-ray imaging of wrist joint dynamic motion

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Carelsen, Bart; Bakker, Niels H.; Strackee, Simon D.; Boon, Sjirk N.; Maas, Mario; Sabczynski, Joerg; Grimbergen, Cornelis A.; Streekstra, Geert J.

2005-01-01

Current methods for imaging joint motion are limited to either two-dimensional (2D) video fluoroscopy, or to animated motions from a series of static three-dimensional (3D) images. 3D movement patterns can be detected from biplane fluoroscopy images matched with computed tomography images. This involves several x-ray modalities and sophisticated 2D to 3D matching for the complex wrist joint. We present a method for the acquisition of dynamic 3D images of a moving joint. In our method a 3D-rotational x-ray (3D-RX) system is used to image a cyclically moving joint. The cyclic motion is synchronized to the x-ray acquisition to yield multiple sets of projection images, which are reconstructed to a series of time resolved 3D images, i.e., four-dimensional rotational x ray (4D-RX). To investigate the obtained image quality parameters the full width at half maximum (FWHM) of the point spread function (PSF) via the edge spread function and the contrast to noise ratio between air and phantom were determined on reconstructions of a bullet and rod phantom, using 4D-RX as well as stationary 3D-RX images. The CNR in volume reconstructions based on 251 projection images in the static situation and on 41 and 34 projection images of a moving phantom were 6.9, 3.0, and 2.9, respectively. The average FWHM of the PSF of these same images was, respectively, 1.1, 1.7, and 2.2 mm orthogonal to the motion and parallel to direction of motion 0.6, 0.7, and 1.0 mm. The main deterioration of 4D-RX images compared to 3D-RX images is due to the low number of projection images used and not to the motion of the object. Using 41 projection images seems the best setting for the current system. Experiments on a postmortem wrist show the feasibility of the method for imaging 3D dynamic joint motion. We expect that 4D-RX will pave the way to improved assessment of joint disorders by detection of 3D dynamic motion patterns in joints

Patellofemoral joint motion

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Stanford, W.; Phelan, J.; Albright, J.; Kathol, M.; Rooholamini, S.A.; El-Khoury, G.Y.; Palutsis, G.R.

1988-01-01

This paper describes the use of ultrafast computed tomography (CT) to obtain dynamic images of the patellofemoral joint during active motion. Thirty-eight patients underwent measurements of tangent offset, bisect offset, congruence angle, patellar tilt angle, lateral patellofemoral angle, sulcus angle, and sulcus depth made during leg movement. Selected parameters were compared with Merchant views. Significant correlations were obtained between Merchant views and comparable ultrafast CT views for all parameters except sulcus angle. Correlations between the other parameters were poor. Cine strips showed two patterns of movement; the patella remained centered either throughout excursion or until the last 20 0 of full extension, when it would sublux laterally

Proximal tibiofibular joint: Rendezvous with a forgotten articulation

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Amitav Sarma

2015-01-01

Full Text Available The proximal tibiofibular joint (PTFJ is a plane type synovial joint. The primary function of the PTFJ is dissipation of torsional stresses applied at the ankle and the lateral tibial bending moments besides a very significant tensile, rather than compressive weight bearing. Though rare, early diagnosis and treatment of the PTFJ dislocation are essential to prevent chronic joint instability and extensive surgical intervention to restore normal PTFJ biomechanics, ankle and knee function, especially in athletes prone to such injuries. PTFJ dislocations often remain undiagnosed in polytrauma scenario with ipsilateral tibial fracture due to the absence of specific signs and symptoms of PTFJ injury. Standard orthopedic textbooks generally describe no specific tests or radiological signs for assessment of the integrity of this joint. The aim of this paper was to review the relevant clinical anatomy, biomechanics and traumatic pathology of PTFJ with its effect on the knee emphasizing the importance of early diagnosis through a high index of suspicion. Dislocation of the joint may have serious implications for the knee joint stability since fibular collateral ligament and posterolateral ligament complex is attached to the upper end of the fibula. Any high energy knee injury with peroneal nerve palsy should immediately raise the suspicion of PTFJ dislocation especially if the mechanism of injury involved knee twisting in flexion beyond 80° and in such cases a comparative radiograph of the contralateral side should be performed. Wider clinical awareness can avoid both embarrassingly extensive surgeries due to diagnostic delays or unnecessary overtreatment due to misinformation on the part of the treating surgeon.

Motion correction improves image quality of dGEMRIC in finger joints

International Nuclear Information System (INIS)

Miese, Falk; Kröpil, Patric; Ostendorf, Benedikt; Scherer, Axel; Buchbender, Christian; Quentin, Michael; Lanzman, Rotem S.; Blondin, Dirk; Schneider, Matthias; Bittersohl, Bernd; Zilkens, Christoph; Jellus, Vladimir; Mamisch, Tallal Ch.; Wittsack, Hans-Jörg

2011-01-01

Purpose: To assess motion artifacts in dGEMRIC of finger joints and to evaluate the effectiveness of motion correction. Materials and methods: In 40 subjects (26 patients with finger arthritis and 14 healthy volunteers) dGEMRIC of metacarpophalangeal joint II was performed. Imaging used a dual flip angle approach (TE 3.72 ms, TR 15 ms, flip angles 5° and 26°). Two sets of T1 maps were calculated for dGEMRIC analysis from the imaging data for each subject: one with and one without motion correction. To compare image quality, visual grading analysis and precision of dGEMRIC measurement of both dGEMRIC maps for each case were evaluated. Results: Motion artifacts were present in 82% (33/40) of uncorrected dGEMRIC maps. Motion artifacts were graded as severe or as rendering evaluation impossible in 43% (17/40) of uncorrected dGEMRIC maps. Motion corrected maps showed significantly less motion artifacts (P < 0.001) and were graded as evaluable in 97% (39/40) of cases. Precision was significantly higher in motion corrected images (coefficient of variation (CV = .176 ± .077), compared to uncorrected images (CV .445 ± .347) (P < .001). Motion corrected dGERMIC was different in volunteers and patients (P = .044), whereas uncorrected dGEMRIC was not (P = .234). Conclusion: Motion correction improves image quality, dGEMRIC measurement precision and diagnostic performance in dGEMRIC of finger joints.

Computer-aided joint space analysis of the metacarpal-phalangeal and proximal-interphalangeal finger joint: normative age-related and gender-specific data

International Nuclear Information System (INIS)

Pfeil, Alexander; Boettcher, Joachim; Seidl, Bettina E.; Heyne, Jens-Peter; Petrovitch, Alexander; Mentzel, Hans-Joachim; Kaiser, Werner A.; Eidner, Torsten; Wolf, Gunter; Hein, Gert

2007-01-01

The purpose of the study was to provide reference data for computer-aided joint space analysis based on a semi-automated and computer-aided diagnostic system for the measurement of metacarpal-phalangeal and proximal-interphalangeal finger joint widths; additionally, the determination of sex differences and the investigation of changes in joint width with age were evaluated. Eighty hundred and sixty-nine patients (351 female and 518 male) received radiographs of the hand for trauma and were screened for a host of conditions known to affect the joint spaces. All participants underwent measurements of joint space distances at the metacarpal-phalangeal articulation (JSD-MCP) from the thumb to the small finger and at the proximal-interphalangeal articulation (JSD-PIP) from the index finger to the small finger using computer-aided diagnosis technology with semi-automated edge detection. The study revealed an annual narrowing of the JSD of 0.6% for the JSD-MCP and for the JSD-PIP. Furthermore, the data demonstrated a notable age-related decrease in JSD, including an accentuated age-related joint space narrowing in women for both articulations. Additionally, males showed a significantly wider JSD-MCP (+11.1%) and JSD-PIP (+15.4%) compared with the female cohort in all age groups. Our data presented gender-specific and age-related normative reference values for computer-aided joint space analysis of the JSD-MCP and JSD-PIP that could be used to identify disease-related joint space narrowing, particularly in patients with osteoarthritis and rheumatoid arthritis commonly involving the peripheral small hand joints. (orig.)

Finger island flaps for treatment of dermato-desmogenic flexion contractures of proximal interphalangeal joints

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T. S. Antonova

2016-12-01

Full Text Available Soft tissue defect will form after operative treatment of the dermato-desmogenic flexion contractures of fingers interphalangeal joints of the 2–3 grades after excision of the scar. Using the island flaps (Littler at the central vascular pedicle is one of the classical methods of plastic closure of such defects. Goal. To study the effectiveness of the surgical treatment of dermato-desmogenic flexion contractures of proximal interphalangeal joints of the fingers by using finger island flaps at the central vascular or neuro-vascular pedicle. Materials and methods. 14 operations were carried out on 13 patients for removing dermato-desmogenic flexion contractures of proximal interphalangeal (PIP joints of triphalangeal fingers over a 2-year period (2013–2015. The group included patients with a flexion contracture of the 2–3 grades PIP joints of triphalangeal fingers. Operations were performed on average 5 months after the injury (from 1.5 up to 16 months. Finger island flap in all cases was taken from adjacent finger by using the blood supply of their common finger artery. In all cases the island flap on the central pedicel was used, in 9 cases digital nerve was included in the pedicle (Littler. Closure of donor wound was made with free-skin grafts. Permanent splinting of the hand with extension of the interphalangeal joints and moderate flexion of the metacarpophalangeal joints were performed during 7–8 days after surgery, then exercise therapy was prescribed. Results. The results were estimated 6 and 12 months after surgery. All the results were regarded as excellent. In 5 cases of using the flap on a vascular pedicle flap hypoesthesia was detected, that has not led to dysfunction of the hand. Contracture recurrence during follow-up was not observed. Conclusions. Using the surgery for treatment of dermato-desmogenic flexion contractures of proximal interphalangeal joints of the fingers with the island flaps at the central vascular or neuro

Frequency-Domain Joint Motion and Disparity Estimation Using Steerable Filters

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Dimitrios Alexiadis

2018-02-01

Full Text Available In this paper, the problem of joint disparity and motion estimation from stereo image sequences is formulated in the spatiotemporal frequency domain, and a novel steerable filter-based approach is proposed. Our rationale behind coupling the two problems is that according to experimental evidence in the literature, the biological visual mechanisms for depth and motion are not independent of each other. Furthermore, our motivation to study the problem in the frequency domain and search for a filter-based solution is based on the fact that, according to early experimental studies, the biological visual mechanisms can be modelled based on frequency-domain or filter-based considerations, for both the perception of depth and the perception of motion. The proposed framework constitutes the first attempt to solve the joint estimation problem through a filter-based solution, based on frequency-domain considerations. Thus, the presented ideas provide a new direction of work and could be the basis for further developments. From an algorithmic point of view, we additionally extend state-of-the-art ideas from the disparity estimation literature to handle the joint disparity-motion estimation problem and formulate an algorithm that is evaluated through a number of experimental results. Comparisons with state-of-the-art-methods demonstrate the accuracy of the proposed approach.

Differences in kinematic control of ankle joint motions in people with chronic ankle instability.

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Kipp, Kristof; Palmieri-Smith, Riann M

2013-06-01

People with chronic ankle instability display different ankle joint motions compared to healthy people. The purpose of this study was to investigate the strategies used to control ankle joint motions between a group of people with chronic ankle instability and a group of healthy, matched controls. Kinematic data were collected from 11 people with chronic ankle instability and 11 matched control subjects as they performed a single-leg land-and-cut maneuver. Three-dimensional ankle joint angles were calculated from 100 ms before, to 200 ms after landing. Kinematic control of the three rotational ankle joint degrees of freedom was investigated by simultaneously examining the three-dimensional co-variation of plantarflexion/dorsiflexion, toe-in/toe-out rotation, and inversion/eversion motions with principal component analysis. Group differences in the variance proportions of the first two principal components indicated that the angular co-variation between ankle joint motions was more linear in the control group, but more planar in the chronic ankle instability group. Frontal and transverse plane motions, in particular, contributed to the group differences in the linearity and planarity of angular co-variation. People with chronic ankle instability use a different kinematic control strategy to coordinate ankle joint motions during a single-leg landing task. Compared to the healthy group, the chronic ankle instability group's control strategy appeared to be more complex and involved joint-specific contributions that would tend to predispose this group to recurring episodes of instability. Copyright © 2013 Elsevier Ltd. All rights reserved.

Proximal fibular osteotomy: a new surgery for pain relief and improvement of joint function in patients with knee osteoarthritis.

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Wang, Xiaohu; Wei, Lei; Lv, Zhi; Zhao, Bin; Duan, Zhiqing; Wu, Wenjin; Zhang, Bin; Wei, Xiaochun

2017-02-01

Objective To explore the effects of proximal fibular osteotomy as a new surgery for pain relief and improvement of medial joint space and function in patients with knee osteoarthritis. Methods From January 2015 to May 2015, 47 patients who underwent proximal fibular osteotomy for medial compartment osteoarthritis were retrospectively followed up. Preoperative and postoperative weight-bearing and whole lower extremity radiographs were obtained to analyse the alignment of the lower extremity and ratio of the knee joint space (medial/lateral compartment). Knee pain was assessed using a visual analogue scale, and knee ambulation activities were evaluated using the American Knee Society score preoperatively and postoperatively. Results Medial pain relief was observed in almost all patients after proximal fibular osteotomy. Most patients exhibited improved walking postoperatively. Weight-bearing lower extremity radiographs showed an average increase in the postoperative medial knee joint space. Additionally, obvious correction of alignment was observed in the whole lower extremity radiographs in 8 of 47 patients. Conclusions The present study demonstrates that proximal fibular osteotomy effectively relieves pain and improves joint function in patients with medial compartment osteoarthritis at a mean of 13.38 months postoperatively.

Changes in ankle joint motion after Supramalleolar osteotomy: a cadaveric model.

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Kim, Hak Jun; Yeo, Eui Dong; Rhyu, Im Joo; Lee, Soon-Hyuck; Lee, Yeon Soo; Lee, Young Koo

2017-09-09

Malalignment of the ankle joint has been found after trauma, by neurological disorders, genetic predisposition and other unidentified factors, and results in asymmetrical joint loading. For a medial open wedge supramalleolar osteotomy(SMO), there are some debates as to whether concurrent fibular osteotomy should be performed. We assessed the changes in motion of ankle joint and plantar pressure after supramalleolar osteotomy without fibular osteotomy. Ten lower leg specimens below the knee were prepared from fresh-frozen human cadavers. They were harvested from five males (10 ankles)whose average age was 70 years. We assessed the motion of ankle joint as well as plantar pressure for SS(supra-syndesmotic) SMO and IS(intra-syndesmotic) SMO. After the osteotomy, each specimen was subjected to axial compression from 20 N preload to 350 N representing half-body weight. For the measurement of the motion of ankle joint, the changes in gap and point, angles in ankle joint were measured. The plantar pressure were also recorded using TekScan sensors. The changes in the various gap, point, and angles movements on SS-SMO and IS-SMO showed no statistically significant differences between the two groups. Regarding the shift of plantar center of force (COF) were noted in the anterolateral direction, but not statistically significant. SS-SMO and IS-SMO with intact fibula showed similar biomechanical effect on the ankle joint. We propose that IS-SMO should be considered carefully for the treatment of osteoarthrosis when fibular osteotomy is not performed because lateral cortex fracture was less likely using the intrasyndesmosis plane because of soft tissue support.

One-degree-of-freedom spherical model for the passive motion of the human ankle joint.

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Sancisi, Nicola; Baldisserri, Benedetta; Parenti-Castelli, Vincenzo; Belvedere, Claudio; Leardini, Alberto

2014-04-01

Mathematical modelling of mobility at the human ankle joint is essential for prosthetics and orthotic design. The scope of this study is to show that the ankle joint passive motion can be represented by a one-degree-of-freedom spherical motion. Moreover, this motion is modelled by a one-degree-of-freedom spherical parallel mechanism model, and the optimal pivot-point position is determined. Passive motion and anatomical data were taken from in vitro experiments in nine lower limb specimens. For each of these, a spherical mechanism, including the tibiofibular and talocalcaneal segments connected by a spherical pair and by the calcaneofibular and tibiocalcaneal ligament links, was defined from the corresponding experimental kinematics and geometry. An iterative procedure was used to optimize the geometry of the model, able to predict original experimental motion. The results of the simulations showed a good replication of the original natural motion, despite the numerous model assumptions and simplifications, with mean differences between experiments and predictions smaller than 1.3 mm (average 0.33 mm) for the three joint position components and smaller than 0.7° (average 0.32°) for the two out-of-sagittal plane rotations, once plotted versus the full flexion arc. The relevant pivot-point position after model optimization was found within the tibial mortise, but not exactly in a central location. The present combined experimental and modelling analysis of passive motion at the human ankle joint shows that a one degree-of-freedom spherical mechanism predicts well what is observed in real joints, although its computational complexity is comparable to the standard hinge joint model.

The Determinants of National Funding in Trans-national Joint Research: Exploring the Proximity Dimensions

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Reale, E.; Spinello, A.; Zinilli, A.

2016-07-01

This paper investigates -using an explorative approach, why policy makers at national level engage in transnational joint research activities and mobilize dedicated financial resources. The research question is: why policy makers (either Governments or Research Funding Organisations-RFOs) in EU28 countries invest in transnational joint research activities beyond the European Framework Programmes, and what are the determinants of different levels of funding engagement? The question is relevant to understand the reasons that generate the existing imbalances within European countries as to the participation in transnational research, which are likely to create peripheries within the ERA, thus undermining the process of European integration. We assume that proximity linked to cognitive, institutional and organizational dimensions can affect the policy decisions about the level of funding (real engagement) joint European research programmes, because the closeness or distance in these dimensions generate similarities that are likely to influence the possibility of decision makers to collaborate in the implementation of research programmes. The paper also explores the existence of any effect of geographical proximity, although it is not supposed to play a role in policy decisions about investment in transnational research programmes. (Author)

Action Recognition by Joint Spatial-Temporal Motion Feature

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Weihua Zhang

2013-01-01

Full Text Available This paper introduces a method for human action recognition based on optical flow motion features extraction. Automatic spatial and temporal alignments are combined together in order to encourage the temporal consistence on each action by an enhanced dynamic time warping (DTW algorithm. At the same time, a fast method based on coarse-to-fine DTW constraint to improve computational performance without reducing accuracy is induced. The main contributions of this study include (1 a joint spatial-temporal multiresolution optical flow computation method which can keep encoding more informative motion information than recent proposed methods, (2 an enhanced DTW method to improve temporal consistence of motion in action recognition, and (3 coarse-to-fine DTW constraint on motion features pyramids to speed up recognition performance. Using this method, high recognition accuracy is achieved on different action databases like Weizmann database and KTH database.

Comparative study of joint range of motion in children between 7 and 12 years of age from different gender

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S.I.L. Melo

2011-01-01

Full Text Available The aim of the study was to evaluate and compare active and passive joint range of motion in children in relation to gender and age. This study involved 103 children (43 boys and 60 girls categorized into two groups: G1 (7 to 9 years old and G2 (10 to 12 years old. The flexitest protocol, active and passive, and the SAPO® were used to evaluate joint range of motion. A paired t test was applied to compare active and passive joint range of motion and an independent t test (p < .05 was used to compare active and passive range of motion between gender and age. Results showed that the passive joint ranges of motion of the lower limbs are higher than active motion (p < .001. Girls presented greater passive ankle flexion than boys did (p = .002. Children between 7 and 12 years of age presented similar standards of joint range of motion of low limb. Significant differences were found between passive and active angular range of motion in the hip, knee and ankle. There were no differences between boys and girls in the joint range of motion as well as among age groups.

[Case control study on therapeutic effects of dynamic external fixtor combined with limited internal fixation and cross K-wires fixation for the treatment of Pilon fractures of the proximal interphalangeal joint].

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Miao, Dao-yi; Yang, Guo-jing; Zhang, Ling-zhou; Wu, Jian-wei

2015-10-01

To compare the clinical effects and safety of dynamic external fixtor combined with limited internal fixation and cross K-wires fixation for the treatment of close Pilon fractures of the proximal interphalangeal joint. From June 2012 to June 2014, totally 41 patients (45 fingers) with close interphalangeal joint Pilon fracture were treated by dynamic external fixtor combined with limited internal fixation or cross K-wires fixation, and all the patients were followed up. In the dynamic external fixtor combined with limited internal fixation group (group A), there were 21 patients with 22 fingers, including 12 males and 9 females, with an average of (30.6±5.6) years old. In the cross K-wires fixation group (group B), there were 20 patients with 23 fingers, including 11 males and 9 females, with an average of (30.1±5.3) years old. Regular re-examination of X-ray was performed to evaluate the active range of joint motion, fracture healing time, infection rate and postoperative joint motion pain. According to the evaluation criteria of upper extremity function issued by the Hand Surgery Society of Chinese Medical Association, the excellent and good cases of group A was up to 19 and 13 for group B. The evaluation results has significant differences (Z=2.558, P=0.011). The excellent and good rate of group A was obviously higher than that of group B. The average bone union time of group A was (7.9±2.1) weeks, and (8.1±2.3) weeks for group B. There was no significant difference on the mean healing time (t=-0.304, P=0.762). The infection fingers of group A was 5, and 1 for group B. The difference between the results was statistically significant (χ2=3.287, Pexternal fixtor combined with limited internal fixation is a reliable and effective method to treat Pilon fractures of the proximal interphalangeal joint. It allows early postoperative functional rehabilitation and restores the joint function.

Do the radial head prosthesis components fit with the anatomical structures of the proximal radioulnar joint?

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Wegmann, Kilian; Hain, Moritz K; Ries, Christian; Neiss, Wolfram F; Müller, Lars P; Burkhart, Klaus J

2015-09-01

The fitting accuracy of radial head components has been investigated in the capitulo-radial joint, and reduced contact after prosthetic replacement of the radial head has been observed. The kinematics of the proximal radioulnar joint (PRUJ) are affected by radial head arthroplasty as well, but have not yet been investigated in this regard. The elbow joints of 60 upper extremities of formalin-fixed body donors were disarticulated to obtain a good view of the PRUJ. Each specimen was mounted on the examining table and radial head position in the native PRUJ was assessed in neutral position, full pronation, and full supination. Measurements were repeated after implantation of mono- and bi-polar prostheses. Analysis of the distribution of the joint contacts in the compartments showed significant differences after radial head replacement. In comparison to the native joint, after bipolar and monopolar radial head replacement, the physiological shift of the proximal radius was altered. The physiological shift of the joint contact of the radial head from anterior to posterior during forearm rotation that was found in the native joint in our cadaver model was not observed after prosthetic replacement. With higher conformity and physiological kinematic of radial head prostheses, possibly lower shear forces and lower contact pressures would be generated. The tested radial head prostheses do not replicate the physiological kinematics of the radial head. Further development in the prosthesis design has to be made. The meticulous reconstruction of the annular ligament seems to be of importance to increase joint contact.

Direct Parametric Reconstruction With Joint Motion Estimation/Correction for Dynamic Brain PET Data.

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Jiao, Jieqing; Bousse, Alexandre; Thielemans, Kris; Burgos, Ninon; Weston, Philip S J; Schott, Jonathan M; Atkinson, David; Arridge, Simon R; Hutton, Brian F; Markiewicz, Pawel; Ourselin, Sebastien

2017-01-01

Direct reconstruction of parametric images from raw photon counts has been shown to improve the quantitative analysis of dynamic positron emission tomography (PET) data. However it suffers from subject motion which is inevitable during the typical acquisition time of 1-2 hours. In this work we propose a framework to jointly estimate subject head motion and reconstruct the motion-corrected parametric images directly from raw PET data, so that the effects of distorted tissue-to-voxel mapping due to subject motion can be reduced in reconstructing the parametric images with motion-compensated attenuation correction and spatially aligned temporal PET data. The proposed approach is formulated within the maximum likelihood framework, and efficient solutions are derived for estimating subject motion and kinetic parameters from raw PET photon count data. Results from evaluations on simulated [ 11 C]raclopride data using the Zubal brain phantom and real clinical [ 18 F]florbetapir data of a patient with Alzheimer's disease show that the proposed joint direct parametric reconstruction motion correction approach can improve the accuracy of quantifying dynamic PET data with large subject motion.

Joint Motion Quality in Chondromalacia Progression Assessed by Vibroacoustic Signal Analysis.

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Bączkowicz, Dawid; Majorczyk, Edyta

2016-11-01

Because of the specific biomechanical environment of the patellofemoral joint, chondral disorders, including chondromalacia, often are observed in this articulation. Chondromalacia via pathologic changes in cartilage may lead to qualitative impairment of knee joint motion. To determine the patellofemoral joint motion quality in particular chondromalacia stages and to compare with controls. Retrospective, comparative study. Voivodship hospitals, university biomechanical laboratory. A total of 89 knees with chondromalacia (25 with stage I; 30 with stage II and 34 with stage III) from 50 patients and 64 control healthy knees (from 32 individuals). Vibroacoustic signal pattern analysis of joint motion quality. For all knees vibroacoustic signals were recorded. Each obtained signal was described by variation of mean square, mean range (R4), and power spectral density for frequency of 50-250 Hz (P1) and 250-450 Hz (P2) parameters. Differences between healthy controls and all chondromalacic knees as well as chondromalacia patellae groups were observed as an increase of analyzed parameters (P chondromalacia patellae was found. All chondromalacia groups were differentiated by the use of all analyzed parameters (P chondromalacia. Chondromalacia generates abnormal vibroacoustic signals, and there seems to be a relationship between the level of signal amplitude as well as frequency and cartilage destruction from the superficial layer to the subchondral bone. IV. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

Models of Postural Control: Shared Variance in Joint and COM Motions.

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Melissa C Kilby

Full Text Available This paper investigated the organization of the postural control system in human upright stance. To this aim the shared variance between joint and 3D total body center of mass (COM motions was analyzed using multivariate canonical correlation analysis (CCA. The CCA was performed as a function of established models of postural control that varied in their joint degrees of freedom (DOF, namely, an inverted pendulum ankle model (2DOF, ankle-hip model (4DOF, ankle-knee-hip model (5DOF, and ankle-knee-hip-neck model (7DOF. Healthy young adults performed various postural tasks (two-leg and one-leg quiet stances, voluntary AP and ML sway on a foam and rigid surface of support. Based on CCA model selection procedures, the amount of shared variance between joint and 3D COM motions and the cross-loading patterns we provide direct evidence of the contribution of multi-DOF postural control mechanisms to human balance. The direct model fitting of CCA showed that incrementing the DOFs in the model through to 7DOF was associated with progressively enhanced shared variance with COM motion. In the 7DOF model, the first canonical function revealed more active involvement of all joints during more challenging one leg stances and dynamic posture tasks. Furthermore, the shared variance was enhanced during the dynamic posture conditions, consistent with a reduction of dimension. This set of outcomes shows directly the degeneracy of multivariate joint regulation in postural control that is influenced by stance and surface of support conditions.

Estimating anatomical wrist joint motion with a robotic exoskeleton.

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Rose, Chad G; Kann, Claudia K; Deshpande, Ashish D; O'Malley, Marcia K

2017-07-01

Robotic exoskeletons can provide the high intensity, long duration targeted therapeutic interventions required for regaining motor function lost as a result of neurological injury. Quantitative measurements by exoskeletons have been proposed as measures of rehabilitative outcomes. Exoskeletons, in contrast to end effector designs, have the potential to provide a direct mapping between human and robot joints. This mapping rests on the assumption that anatomical axes and robot axes are aligned well, and that movement within the exoskeleton is negligible. These assumptions hold well for simple one degree-of-freedom joints, but may not be valid for multi-articular joints with unique musculoskeletal properties such as the wrist. This paper presents an experiment comparing robot joint kinematic measurements from an exoskeleton to anatomical joint angles measured with a motion capture system. Joint-space position measurements and task-space smoothness metrics were compared between the two measurement modalities. The experimental results quantify the error between joint-level position measurements, and show that exoskeleton kinematic measurements preserve smoothness characteristics found in anatomical measures of wrist movements.

Exit from Synchrony in Joint Improvised Motion.

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Assi Dahan

Full Text Available Motion synchrony correlates with effective and well-rated human interaction. However, people do not remain locked in synchrony; Instead, they repeatedly enter and exit synchrony. In many important interactions, such as therapy, marriage and parent-infant communication, it is the ability to exit and then re-enter synchrony that is thought to build strong relationship. The phenomenon of entry into zero-phase synchrony is well-studied experimentally and in terms of mathematical modeling. In contrast, exit-from-synchrony is under-studied. Here, we focus on human motion coordination, and examine the exit-from-synchrony phenomenon using experimental data from the mirror game paradigm, in which people perform joint improvised motion, and from human tracking of computer-generated stimuli. We present a mathematical mechanism that captures aspects of exit-from-synchrony in human motion. The mechanism adds a random motion component when the accumulated velocity error between the players is small. We introduce this mechanism to several models for human coordinated motion, including the widely studied HKB model, and the predictor-corrector model of Noy, Dekel and Alon. In all models, the new mechanism produces realistic simulated behavior when compared to experimental data from the mirror game and from tracking of computer generated stimuli, including repeated entry and exit from zero-phase synchrony that generates a complexity of motion similar to that of human players. We hope that these results can inform future research on exit-from-synchrony, to better understand the dynamics of coordinated action of people and to enhance human-computer and human-robot interaction.

Lower limb joint motion during a cross cutting movement differs in individuals with and without chronic ankle instability.

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Koshino, Yuta; Yamanaka, Masanori; Ezawa, Yuya; Ishida, Tomoya; Kobayashi, Takumi; Samukawa, Mina; Saito, Hiroshi; Takeda, Naoki

2014-11-01

To compare the kinematics of lower limb joints between individuals with and without chronic ankle instability (CAI) during cross-turn and -cutting movements. Cross-sectional study. Motion analysis laboratory. Twelve subjects with CAI and twelve healthy controls. Hip flexion, adduction, and internal rotation, knee flexion, and ankle dorsiflexion and inversion angles were calculated in the 200 ms before initial ground contact and from initial ground contact to toe-off (stance phase) in a cross-turn movement during gait and a cross-cutting movement from a forward jump, and compared across the two groups. In the cross-cutting movement, the CAI group exhibited greater hip and knee flexion than the control group during the stance phase, and more hip abduction during the period before initial contact and the stance phase. In the cross-turn movement the joint kinematics were similar in the two groups. CAI subjects exhibited an altered pattern of the proximal joint kinematics during a cross-cutting movement. It is important for clinicians to assess the function of the hip and knee as well as the ankle, and to incorporate coordination training for the entire lower limb into rehabilitation after lateral ankle sprains. Copyright © 2013 Elsevier Ltd. All rights reserved.

Proximal Humerus

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Diercks, Ron L.; Bain, Gregory; Itoi, Eiji; Di Giacomo, Giovanni; Sugaya, Hiroyuki

2015-01-01

This chapter describes the bony structures of the proximal humerus. The proximal humerus is often regarded as consisting of four parts, which assists in understanding function and, more specially, describes the essential parts in reconstruction after fracture or in joint replacement. These are the

Electromagnetic tracking of motion in the proximity of computer generated graphical stimuli: a tutorial.

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Schnabel, Ulf H; Hegenloh, Michael; Müller, Hermann J; Zehetleitner, Michael

2013-09-01

Electromagnetic motion-tracking systems have the advantage of capturing the tempo-spatial kinematics of movements independently of the visibility of the sensors. However, they are limited in that they cannot be used in the proximity of electromagnetic field sources, such as computer monitors. This prevents exploiting the tracking potential of the sensor system together with that of computer-generated visual stimulation. Here we present a solution for presenting computer-generated visual stimulation that does not distort the electromagnetic field required for precise motion tracking, by means of a back projection medium. In one experiment, we verify that cathode ray tube monitors, as well as thin-film-transistor monitors, distort electro-magnetic sensor signals even at a distance of 18 cm. Our back projection medium, by contrast, leads to no distortion of the motion-tracking signals even when the sensor is touching the medium. This novel solution permits combining the advantages of electromagnetic motion tracking with computer-generated visual stimulation.

Multiple intramedullary nailing of proximal phalangeal fractures of hand

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Patankar Hemant

2008-01-01

Full Text Available Background: Proximal phalangeal fractures are commonly encountered fractures in the hand. Majority of them are stable and can be treated by non-operative means. However, unstable fractures i.e. those with shortening, displacement, angulation, rotational deformity or segmental fractures need surgical intervention. This prospective study was undertaken to evaluate the functional outcome after surgical stabilization of these fractures with joint-sparing multiple intramedullary nailing technique. Materials and Methods: Thirty-five patients with 35 isolated unstable proximal phalangeal shaft fractures of hand were managed by surgical stabilization with multiple intramedullary nailing technique. Fractures of the thumb were excluded. All the patients were followed up for a minimum of six months. They were assessed radiologically and clinically. The clinical evaluation was based on two criteria. 1. total active range of motion for digital functional assessment as suggested by the American Society for Surgery of Hand and 2. grip strength. Results: All the patients showed radiological union at six weeks. The overall results were excellent in all the patients. Adventitious bursitis was observed at the point of insertion of nails in one patient. Conclusion: Joint-sparing multiple intramedullary nailing of unstable proximal phalangeal fractures of hand provides satisfactory results with good functional outcome and fewer complications.

Reliability and concurrent validity of a Smartphone, bubble inclinometer and motion analysis system for measurement of hip joint range of motion.

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Charlton, Paula C; Mentiplay, Benjamin F; Pua, Yong-Hao; Clark, Ross A

2015-05-01

Traditional methods of assessing joint range of motion (ROM) involve specialized tools that may not be widely available to clinicians. This study assesses the reliability and validity of a custom Smartphone application for assessing hip joint range of motion. Intra-tester reliability with concurrent validity. Passive hip joint range of motion was recorded for seven different movements in 20 males on two separate occasions. Data from a Smartphone, bubble inclinometer and a three dimensional motion analysis (3DMA) system were collected simultaneously. Intraclass correlation coefficients (ICCs), coefficients of variation (CV) and standard error of measurement (SEM) were used to assess reliability. To assess validity of the Smartphone application and the bubble inclinometer against the three dimensional motion analysis system, intraclass correlation coefficients and fixed and proportional biases were used. The Smartphone demonstrated good to excellent reliability (ICCs>0.75) for four out of the seven movements, and moderate to good reliability for the remaining three movements (ICC=0.63-0.68). Additionally, the Smartphone application displayed comparable reliability to the bubble inclinometer. The Smartphone application displayed excellent validity when compared to the three dimensional motion analysis system for all movements (ICCs>0.88) except one, which displayed moderate to good validity (ICC=0.71). Smartphones are portable and widely available tools that are mostly reliable and valid for assessing passive hip range of motion, with potential for large-scale use when a bubble inclinometer is not available. However, caution must be taken in its implementation as some movement axes demonstrated only moderate reliability. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Electrical Properties of PPy-Coated Conductive Fabrics for Human Joint Motion Monitoring

Directory of Open Access Journals (Sweden)

Jiyong Hu

2016-03-01

Full Text Available Body motion signals indicate several pathological features of the human body, and a wearable human motion monitoring system can respond to human joint motion signal in real time, thereby enabling the prevention and treatment of some diseases. Because conductive fabrics can be well integrated with the garment, they are ideal as a sensing element of wearable human motion monitoring systems. This study prepared polypyrrole conductive fabric by in situ polymerization, and the anisotropic property of the conductive fabric resistance, resistance–strain relationship, and the relationship between resistance and the human knee and elbow movements are discussed preliminarily.

First metatarsophalangeal joint motion in Homo sapiens: theoretical association of two-axis kinematics and specific morphometrics.

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Durrant, Michael N; McElroy, Tucker; Durrant, Lara

2012-01-01

The metatarsal head and proximal phalanx exhibit considerable asymmetry in their shape and geometry, but there is little documentation in the literature regarding the prevalence of structural characteristics that occur in a given population. Although there is a considerable volume of in vivo and in vitro experiments demonstrating first metatarsal inversion around its longitudinal axis with dorsiflexion, little is known regarding the applicability of specific morphometrics to these motions. Nine distinctive osseous characteristics in the metatarsal head and phalanx were selected based on their location, geometry, and perceived functional relationship to previous studies describing metatarsal motion as inversion with dorsiflexion. The prevalences of the chosen characteristics were determined in a cohort of 21 randomly selected skeletal specimens, 19 of which were provided by the anatomical preparation office at the University of California, San Diego, and two of which were in the possession of one of us (M.D.). The frequency of occurrence of each selected morphological characteristic in this sample and the relevant summary statistics confirm a strong association between the selected features and a conceptual two-axis kinematic model of the metatarsophalangeal joint. The selected morphometrics are consistent with inversion of the metatarsal around its longitudinal axis as it dorsiflexes.

MRI with microscopy coil of the proximal interphalangeal joints: preliminary study

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Liu Min; Sun Haixing; Liu Dimin; Hu Meiyu; Pan Shunping; Wang Ping; Huang Xiaoling; Men Quanfei; Chen Yingming

2009-01-01

Objective: To investigate the use of a microscopy coil in MR examination of proximal interphalangeal joints (PIJ) to collect evidence on micro-anatomical pathological changes for further MR diagnosis. Methods: Four PIJ in cadaver and 12 PIJ from 7 normal volunteers were scanned with a microscopy surface coil (23 mm in diameter) at 1.5 T MRI. Sagittal T 1 -weighted images were also obtained with a conventional surface coil using the same parameters for the volunteers. Based on the observation of sagittal, traverse, coronal PIJ imaging features of cadaver, the optimized sequences were chosen for the volunteer's application. Image quality of the PIJ structures from volunteers was analyzed by two radiologists on a 5-point scale (0, nonvisualization; 1, poor; 2, average; 3, good; 4, excellent) and compared with Wilcoxon signed tank test between the microscopy and C3 surface coil in sagittal direction. Results: With microscopy coil all sequences can visualize the main structures of PI J, and all the PIJ images were classified as good or excellent except for one as average, while all the 12 PIJ with C3 coil were classified as poor or invisible. PIJ structures (proximal phalanx head, middle phalanx base, cartilage, volar plate) from volunteers show higher scores of quality with microscopy coils than those with C3 coil, and the difference was significant (Z =-3.274, -3.274, -3.213, and -3.742 respectively, all P<0.01). Conclusion: High-resolution MRI of the normal PIJ with microscopy coil was superior to those with a conventional surface coil, and it can be a promising method to diagnose interphalangeal joints lesions. (authors)

Whole-body patterns of the range of joint motion in young adults: masculine type and feminine type.

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Moromizato, Keiichi; Kimura, Ryosuke; Fukase, Hitoshi; Yamaguchi, Kyoko; Ishida, Hajime

2016-10-01

Understanding the whole-body patterns of joint flexibility and their related biological and physical factors contributes not only to clinical assessments but also to the fields of human factors and ergonomics. In this study, ranges of motion (ROMs) at limb and trunk joints of young adults were analysed to understand covariation patterns of different joint motions and to identify factors associated with the variation in ROM. Seventy-eight healthy volunteers (42 males and 36 females) living on Okinawa Island, Japan, were recruited. Passive ROM was measured at multiple joints through the whole body (31 measurements) including the left and right side limbs and trunk. Comparisons between males and females, dominant and non-dominant sides, and antagonistic motions indicated that body structures influence ROMs. In principal component analysis (PCA) on the ROM data, the first principal component (PC1) represented the sex difference and a similar covariation pattern appeared in the analysis within each sex. Multiple regression analysis showed that this component was associated with sex, age, body fat %, iliospinale height, and leg extension strength. The present study identified that there is a spectrum of "masculine" and "feminine" types in the whole-body patterns of joint flexibility. This study also suggested that body proportion and composition, muscle mass and strength, and possibly skeletal structures partly explain such patterns. These results would be important to understand individual variation in susceptibility to joint injuries and diseases and in one's suitable and effective postures and motions.

Lower limb joint kinetics and ankle joint stiffness in the sprint start push-off.

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Charalambous, Laura; Irwin, Gareth; Bezodis, Ian N; Kerwin, David

2012-01-01

Sprint push-off technique is fundamental to sprint performance and joint stiffness has been identified as a performance-related variable during dynamic movements. However, joint stiffness for the push-off and its relationship with performance (times and velocities) has not been reported. The aim of this study was to quantify and explain lower limb net joint moments and mechanical powers, and ankle stiffness during the first stance phase of the push-off. One elite sprinter performed 10 maximal sprint starts. An automatic motion analysis system (CODA, 200 Hz) with synchronized force plates (Kistler, 1000 Hz) collected kinematic profiles at the hip, knee, and ankle and ground reaction forces, providing input for inverse dynamics analyses. The lower-limb joints predominately extended and revealed a proximal-to-distal sequential pattern of maximal extensor angular velocity and positive power production. Pearson correlations revealed relationships (P push-off in different ways, depending on the phase of stance considered.

Elbow helical axes of motion are not the same in physiologic and kinetic joint simulators.

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Muriuki, Muturi G; Mohagheh-Motlagh, Amin; Smolinski, Patrick J; Miller, Mark Carl

2012-08-31

Physiologic and kinetic joint simulators have been widely used for investigations of joint mechanics. The two types of simulator differ in the way joint motion is achieved; through prescribed motions and/or forces in kinetic joint simulators and by tendon loads in physiologic joint simulators. These two testing modalities have produced important insights, as in elucidating the importance of soft tissue structures to joint stability. However, the equivalence of the modalities has not been tested. This study sequentially tested five cadaveric elbows using both a physiologic simulator and a robot/6DOF system. Using position data from markers on the humerus and ulna, we calculated and compared the helical axes of motion of the specimens as the elbows were flexed from full extension. Six step size increments were used in the helical axis calculation. Marker position data at each test's full extension and full flexion point were also used to calculate a datum (overall) helical axis. The angles between the datum axis and step-wise movements were computed and stored. Increasing step size monotonically decreased the variability and the average conical angle encompassing the helical axes; a repeated measures ANOVA using test type (robot or physiologic simulator) and step size found that both type and step caused statistically significant differences (p<0.001). The large changes in helical axis angle observed for small changes in elbow flexion angle, especially in the robot tests, are a caveat for investigators using similar control algorithms. Controllers may need to include increased joint compliance and/or C(1) continuity to reduce variability. Copyright © 2012 Elsevier Ltd. All rights reserved.

Analyzing the effects of human-aware motion planning on close-proximity human-robot collaboration.

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Lasota, Przemyslaw A; Shah, Julie A

2015-02-01

The objective of this work was to examine human response to motion-level robot adaptation to determine its effect on team fluency, human satisfaction, and perceived safety and comfort. The evaluation of human response to adaptive robotic assistants has been limited, particularly in the realm of motion-level adaptation. The lack of true human-in-the-loop evaluation has made it impossible to determine whether such adaptation would lead to efficient and satisfying human-robot interaction. We conducted an experiment in which participants worked with a robot to perform a collaborative task. Participants worked with an adaptive robot incorporating human-aware motion planning and with a baseline robot using shortest-path motions. Team fluency was evaluated through a set of quantitative metrics, and human satisfaction and perceived safety and comfort were evaluated through questionnaires. When working with the adaptive robot, participants completed the task 5.57% faster, with 19.9% more concurrent motion, 2.96% less human idle time, 17.3% less robot idle time, and a 15.1% greater separation distance. Questionnaire responses indicated that participants felt safer and more comfortable when working with an adaptive robot and were more satisfied with it as a teammate than with the standard robot. People respond well to motion-level robot adaptation, and significant benefits can be achieved from its use in terms of both human-robot team fluency and human worker satisfaction. Our conclusion supports the development of technologies that could be used to implement human-aware motion planning in collaborative robots and the use of this technique for close-proximity human-robot collaboration.

Patellofemoral joint motion: Evaluation by ultrafast computed tomography

International Nuclear Information System (INIS)

Stanford, W.; Phelan, J.; Kathol, M.H.; Rooholamini, S.A.; El-Khoury, G.Y.; Palutsis, G.R.; Albright, J.P.

1988-01-01

Patellofemoral maltracking is a recognized cause of peripatellar pain. Clinicians currently rely on observation, palpation, and static radiographic images to evaluate the symptomatic patient. Ultrafast computed tomography (ultrafast CT) offers objective observations of the dynamic influences of muscle contraction on the patellofemoral joint as the knee is actively moved through a range of motion from 90 0 C flexion of full extension. This study reports our initial observations and establishes a range of normal values so that patients with a clinical suspicion of patellar maltracking may be evaluated. (orig./GDG)

Patellofemoral joint motion: Evaluation by ultrafast computed tomography

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Stanford, W.; Phelan, J.; Kathol, M.H.; Rooholamini, S.A.; El-Khoury, G.Y.; Palutsis, G.R.; Albright, J.P.

1988-10-01

Patellofemoral maltracking is a recognized cause of peripatellar pain. Clinicians currently rely on observation, palpation, and static radiographic images to evaluate the symptomatic patient. Ultrafast computed tomography (ultrafast CT) offers objective observations of the dynamic influences of muscle contraction on the patellofemoral joint as the knee is actively moved through a range of motion from 90/sup 0/C flexion of full extension. This study reports our initial observations and establishes a range of normal values so that patients with a clinical suspicion of patellar maltracking may be evaluated. (orig./GDG).

Consequences of Avulsion Fracture of the Proximal Phalanx Caused by a Technical Failure of Hallux Valgus Surgery.

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Park, Young Uk; Lee, Kyung Tai; Jegal, Hyuk; Kim, Ki Chun; Choo, Ho Sik; Kweon, Heon Ju

2016-01-01

Several cases of avulsion fracture of the proximal phalanx of the big toe during the lateral capsular release procedure were observed. However, these fractures have not been reported as a complication of hallux valgus surgery. The purpose of the present study was to report the proximal phalanx base fracture as an unrecognized complication and to evaluate the clinical and radiographic consequences of this complication. We retrospectively reviewed 225 feet that had undergone hallux valgus surgery involving proximal chevron osteotomy and distal soft tissue release from May 2009 to December 2012. Of these 225 feet (198 patients), 12 (5.3%) developed proximal phalanx base fracture postoperatively. These patients were assigned to the fracture group. The remaining patients were assigned to the nonfracture group. Patients were followed to observe whether the fractures united and whether degenerative changes developed at the first metatarsophalangeal joint because of this fracture. The mean follow-up period was 36 (range 12 to 72) months. All the subjects in the fracture and nonfracture groups underwent weightbearing anteroposterior and lateral radiographs of the foot at the initial presentation and final follow-up point. The 2 groups were compared with respect to the hallux valgus angle, intermetatarsal angle, range of motion, American Orthopaedic Foot and Ankle Society score, satisfaction, and degenerative changes. No significant differences were found in age, follow-up period, hallux valgus angle, intermetatarsal angle, range of motion of the first metatarsophalangeal joint, American Orthopaedic Foot and Ankle Society score, satisfaction, and degenerative changes between the 2 groups. Ten (83.3%) of the 12 fractures healed, 2 (16.7% of the fractures, 0.89% of the operated feet) progressed to asymptomatic nonunion, and 3 (1.33%) developed first metatarsophalangeal joint degeneration. Avulsion fracture of the proximal phalanx of the big toe is an uncommon complication of

Knee joint contact mechanics during downhill gait and its relationship with varus/valgus motion and muscle strength in patients with knee osteoarthritis.

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Farrokhi, Shawn; Voycheck, Carrie A; Gustafson, Jonathan A; Fitzgerald, G Kelley; Tashman, Scott

2016-01-01

The objective of this exploratory study was to evaluate tibiofemoral joint contact point excursions and velocities during downhill gait and assess the relationship between tibiofemoral joint contact mechanics with frontal-plane knee joint motion and lower extremity muscle weakness in patients with knee osteoarthritis (OA). Dynamic stereo X-ray was used to quantify tibiofemoral joint contact mechanics and frontal-plane motion during the loading response phase of downhill gait in 11 patients with knee OA and 11 control volunteers. Quantitative testing of the quadriceps and the hip abductor muscles was also performed. Patients with knee OA demonstrated larger medial/lateral joint contact point excursions (p knee OA compared to their control counterparts (p = 0.02). Additionally, patients with knee OA demonstrated significantly increased frontal-plane varus motion excursions (p knee OA were linearly associated with greater frontal-plane varus motion excursions (p knee OA may be related to compromised frontal-plane joint stability but not with deficits in muscle strength.

Analyzing the Effects of Human-Aware Motion Planning on Close-Proximity Human–Robot Collaboration

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Shah, Julie A.

2015-01-01

Objective: The objective of this work was to examine human response to motion-level robot adaptation to determine its effect on team fluency, human satisfaction, and perceived safety and comfort. Background: The evaluation of human response to adaptive robotic assistants has been limited, particularly in the realm of motion-level adaptation. The lack of true human-in-the-loop evaluation has made it impossible to determine whether such adaptation would lead to efficient and satisfying human–robot interaction. Method: We conducted an experiment in which participants worked with a robot to perform a collaborative task. Participants worked with an adaptive robot incorporating human-aware motion planning and with a baseline robot using shortest-path motions. Team fluency was evaluated through a set of quantitative metrics, and human satisfaction and perceived safety and comfort were evaluated through questionnaires. Results: When working with the adaptive robot, participants completed the task 5.57% faster, with 19.9% more concurrent motion, 2.96% less human idle time, 17.3% less robot idle time, and a 15.1% greater separation distance. Questionnaire responses indicated that participants felt safer and more comfortable when working with an adaptive robot and were more satisfied with it as a teammate than with the standard robot. Conclusion: People respond well to motion-level robot adaptation, and significant benefits can be achieved from its use in terms of both human–robot team fluency and human worker satisfaction. Application: Our conclusion supports the development of technologies that could be used to implement human-aware motion planning in collaborative robots and the use of this technique for close-proximity human–robot collaboration. PMID:25790568

Computed tomographic method for measurement of inclination angles and motion of the sacroiliac joints in German Shepherd Dogs and Greyhounds.

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Saunders, Fritha C; Cave, Nick J; Hartman, Karl M; Gee, Erica K; Worth, Andrew J; Bridges, Janis P; Hartman, Angela C

2013-09-01

To develop an in vivo CT method to measure inclination angles and motion of the sacroiliac joints in dogs of performance breeds. 10 German Shepherd Dogs and 12 Greyhounds without signs of lumbosacral region pain or neurologic problems. CT of the ilium and sacrum was performed in flexed, neutral, and extended hind limb positions. Lines were drawn on volume-rendered images acquired in the flexed and extended positions to measure motion of the ilia relative to the sacra. Inclination angles of the synovial and ligamentous components of the sacroiliac joints were measured on transverse-plane CT images acquired at cranial and caudal locations. Coefficients of variance of measurements were calculated to determine intraobserver variability. Coefficients of variance of measurements ranged from 0.17% to 2.45%. A significantly higher amount of sacroiliac joint rotational motion was detected for German Shepherd Dogs versus Greyhounds. The cranial synovial joint component had a significantly more sagittal orientation in German Shepherd Dogs versus Greyhounds. No significant differences were detected between breeds for x- or y-axis translational motion or caudal synovial or ligamentous joint component inclination angles. The small amounts of sacroiliac joint motion detected in this study may buffer high-frequency vibrations during movement of dogs. Differences detected between breeds may be associated with the predisposition of German Shepherd Dogs to develop lumbosacral region signs of pain, although the biological importance of this finding was not determined. Future studies are warranted to compare sacroiliac joint variables between German Shepherd Dogs with and without lumbosacral region signs of pain.

POD evaluation for joint angles from inertial and optical motion capturing system

International Nuclear Information System (INIS)

Shimizu, Kai; Kobayashi, Futoshi; Nakamoto, Hiroyuki; Kojima, Fumio

2016-01-01

It has been recognized that advances in preventive maintenance can improve the sustainment of systems, facilities, and infrastructure. Robot technologies have also received attention for maintenance applications. In order to operate delicate tasks, multi-fingered robot hands have been proposed in cases where human capability is deficient. This paper deals with motion capturing systems for controlling the hand/arm robot remotely. Several types of motion capturing systems have been developed so far. However, it is difficult for individual motion capturing systems to measure precise joint angles of a human arm. Therefore, in this paper, we integrate the inertial motion capturing system with the optical motion capturing system to capture a human arm posture. By evaluating the reliability of each motion capturing system, the integration is carried out. The probability of detection (POD) is applied to evaluate and compare the reliability of datasets measured by each motion capturing system. POD is one of the widely used statistical techniques to determine reliability. We apply the â analysis to determine the POD(a) function from the data set. Based on the POD evaluation, two motion capturing systems are integrated. (author)

The effect of glenosphere diameter in reverse shoulder arthroplasty on muscle force, joint load, and range of motion.

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Langohr, G Daniel G; Giles, Joshua W; Athwal, George S; Johnson, James A

2015-06-01

Little is known about the effects of glenosphere diameter on shoulder joint loads. The purpose of this biomechanical study was to investigate the effects of glenosphere diameter on joint load, load angle, and total deltoid force required for active abduction and range of motion in internal/external rotation and abduction. A custom, instrumented reverse shoulder arthroplasty implant system capable of measuring joint load and varying glenosphere diameter (38 and 42 mm) and glenoid offset (neutral and lateral) was implanted in 6 cadaveric shoulders to provide at least 80% power for all variables. A shoulder motion simulator was used to produce active glenohumeral and scapulothoracic motion. All implant configurations were tested with active and passive motion with joint kinematics, loads, and moments recorded. At neutral and lateralized glenosphere positions, increasing diameter significantly increased joint load (+12 ± 21 N and +6 ± 9 N; P  .8). Passive internal rotation was reduced with increased diameter at both neutral and lateralized glenosphere positions (-6° ± 6° and -12° ± 6°; P  .05). At neutral glenosphere position, increasing diameter increased the maximum angles of both adduction (+1° ± 1°; P = .03) and abduction (+8° ± 9°; P < .05). Lateralization also increased abduction range of motion compared with neutral (P < .01). Although increasing glenosphere diameter significantly increased joint load and deltoid force, the clinical impact of these changes is presently unclear. Internal rotation, however, was reduced, which contradicts previous bone modeling studies, which we postulate is due to increased posterior capsular tension as it is forced to wrap around a larger 42 mm implant assembly. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Assessment of congruence and impingement of the hip joint in professional ballet dancers: a motion capture study.

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Charbonnier, Caecilia; Kolo, Frank C; Duthon, Victoria B; Magnenat-Thalmann, Nadia; Becker, Christoph D; Hoffmeyer, Pierre; Menetrey, Jacques

2011-03-01

Early hip osteoarthritis in dancers could be explained by femoroacetabular impingements. However, there is a lack of validated noninvasive methods and dynamic studies to ascertain impingement during motion. Moreover, it is unknown whether the femoral head and acetabulum are congruent in typical dancing positions. The practice of some dancing movements could cause a loss of hip joint congruence and recurrent impingements, which could lead to early osteoarthritis. Descriptive laboratory study. Eleven pairs of female dancer's hips were motion captured with an optical tracking system while performing 6 different dancing movements. The resulting computed motions were applied to patient-specific hip joint 3-dimensional models based on magnetic resonance images. While visualizing the dancer's hip in motion, the authors detected impingements using computer-assisted techniques. The range of motion and congruence of the hip joint were also quantified in those 6 recorded dancing movements. The frequency of impingement and subluxation varied with the type of movement. Four dancing movements (développé à la seconde, grand écart facial, grand écart latéral, and grand plié) seem to induce significant stress in the hip joint, according to the observed high frequency of impingement and amount of subluxation. The femoroacetabular translations were high (range, 0.93 to 6.35 mm). For almost all movements, the computed zones of impingement were mainly located in the superior or posterosuperior quadrant of the acetabulum, which was relevant with respect to radiologically diagnosed damaged zones in the labrum. All dancers' hips were morphologically normal. Impingements and subluxations are frequently observed in typical ballet movements, causing cartilage hypercompression. These movements should be limited in frequency. The present study indicates that some dancing movements could damage the hip joint, which could lead to early osteoarthritis.

Application Of Three-Dimensional Videography To Human Motion Studies: Constraints, Assumptions, And Mathematics

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Rab, George T.

1988-02-01

Three-dimensional human motion analysis has been used for complex kinematic description of abnormal gait in children with neuromuscular disease. Multiple skin markers estimate skeletal segment position, and a sorting and smoothing routine provides marker trajectories. The position and orientation of the moving skeleton in space are derived mathematically from the marker positions, and joint motions are calculated from the Eulerian transformation matrix between linked proximal and distal skeletal segments. Reproduceability has been excellent, and the technique has proven to be a useful adjunct to surgical planning.

Enhancing the smoothness of joint motion induced by functional electrical stimulation using co-activation strategies

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Ruppel Mirjana

2017-09-01

Full Text Available The motor precision of today’s neuroprosthetic devices that use artificial generation of limb motion using Functional Electrical Stimulation (FES is generally low. We investigate the adoption of natural co-activation strategies as present in antagonistic muscle pairs aiming to improve motor precision produced by FES. In a test in which artificial knee-joint movements were generated, we could improve the smoothness of FES-induced motion by 513% when applying co-activation during the phases in which torque production is switched between muscles – compared to no co-activation. We further demonstrated how the co-activation level influences the joint stiffness in a pendulum test.

Wearable Stretch Sensors for Motion Measurement of the Wrist Joint Based on Dielectric Elastomers.

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Huang, Bo; Li, Mingyu; Mei, Tao; McCoul, David; Qin, Shihao; Zhao, Zhanfeng; Zhao, Jianwen

2017-11-23

Motion capture of the human body potentially holds great significance for exoskeleton robots, human-computer interaction, sports analysis, rehabilitation research, and many other areas. Dielectric elastomer sensors (DESs) are excellent candidates for wearable human motion capture systems because of their intrinsic characteristics of softness, light weight, and compliance. In this paper, DESs were applied to measure all component motions of the wrist joints. Five sensors were mounted to different positions on the wrist, and each one is for one component motion. To find the best position to mount the sensors, the distribution of the muscles is analyzed. Even so, the component motions and the deformation of the sensors are coupled; therefore, a decoupling method was developed. By the decoupling algorithm, all component motions can be measured with a precision of 5°, which meets the requirements of general motion capture systems.

Glenoid labrum ossification and mechanical restriction of joint motion: extraosseous manifestations of melorheostosis.

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Subhas, N; Sundaram, M; Bauer, T W; Seitz, W H; Recht, M P

2008-02-01

We report a case of a 47-year-old man who presented with progressive loss of motion and pain in the right shoulder. Radiographs of the shoulder demonstrated dense ossification in the glenoid and humeral head with extension into the periarticular soft tissues. CT and MRI scans confirmed the radiographic findings and also revealed ossification of the glenoid labrum. A radiographic diagnosis of melorheostosis, an uncommon benign sclerosing bone dysplasia, was made. Because of the patient's severe symptomatology, he underwent total shoulder arthroplasty. Histological analysis of the resected masses was consistent with melorheostosis with a few areas covered by a cartilage cap. This case illustrates several uncommon but important features of melorheostosis, including mechanical obstruction of joint motion requiring joint replacement, ossification of the glenoid labrum, and cartilage-covering portions of the intra-articular masses, not to be confused with cartilage-producing tumors.

Philosophies Applied in the Selection of Space Suit Joint Range of Motion Requirements

Science.gov (United States)

Aitchison, Lindsway; Ross, Amy; Matty, Jennifer

2009-01-01

Space suits are the most important tool for astronauts working in harsh space and planetary environments; suits keep crewmembers alive and allow them to perform exploration, construction, and scientific tasks on a routine basis over a period of several months. The efficiency with which the tasks are performed is largely dictated by the mobility features of the space suit. For previous space suit development programs, the mobility requirements were written as pure functional mobility requirements that did not separate joint ranges of motion from the joint torques. The Constellation Space Suit Element has the goal to make more quantitative mobility requirements that focused on the individual components of mobility to enable future suit designers to build and test systems more effectively. This paper details the test planning and selection process for the Constellation space suit pressure garment range of motion requirements.

Glenoid labrum ossification and mechanical restriction of joint motion: extraosseous manifestations of melorheostosis

International Nuclear Information System (INIS)

Subhas, N.; Sundaram, M.; Recht, M.P.; Bauer, T.W.; Seitz, W.H.

2008-01-01

We report a case of a 47-year-old man who presented with progressive loss of motion and pain in the right shoulder. Radiographs of the shoulder demonstrated dense ossification in the glenoid and humeral head with extension into the periarticular soft tissues. CT and MRI scans confirmed the radiographic findings and also revealed ossification of the glenoid labrum. A radiographic diagnosis of melorheostosis, an uncommon benign sclerosing bone dysplasia, was made. Because of the patient's severe symptomatology, he underwent total shoulder arthroplasty. Histological analysis of the resected masses was consistent with melorheostosis with a few areas covered by a cartilage cap. This case illustrates several uncommon but important features of melorheostosis, including mechanical obstruction of joint motion requiring joint replacement, ossification of the glenoid labrum, and cartilage-covering portions of the intra-articular masses, not to be confused with cartilage-producing tumors. (orig.)

Glenoid labrum ossification and mechanical restriction of joint motion: extraosseous manifestations of melorheostosis

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Subhas, N.; Sundaram, M.; Recht, M.P. [Cleveland Clinic, Department of Diagnostic Radiology, Cleveland, OH (United States); Bauer, T.W. [Cleveland Clinic, Department of Anatomic Pathology, Cleveland, OH (United States); Seitz, W.H. [Cleveland Clinic, Department of Orthopaedic Surgery, Cleveland, OH (United States)

2008-02-15

We report a case of a 47-year-old man who presented with progressive loss of motion and pain in the right shoulder. Radiographs of the shoulder demonstrated dense ossification in the glenoid and humeral head with extension into the periarticular soft tissues. CT and MRI scans confirmed the radiographic findings and also revealed ossification of the glenoid labrum. A radiographic diagnosis of melorheostosis, an uncommon benign sclerosing bone dysplasia, was made. Because of the patient's severe symptomatology, he underwent total shoulder arthroplasty. Histological analysis of the resected masses was consistent with melorheostosis with a few areas covered by a cartilage cap. This case illustrates several uncommon but important features of melorheostosis, including mechanical obstruction of joint motion requiring joint replacement, ossification of the glenoid labrum, and cartilage-covering portions of the intra-articular masses, not to be confused with cartilage-producing tumors. (orig.)

[The randomized controlled trial of influences of T shape approach on the function of knee joint in the treatment of proximal tibial fractures].

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Peng, Wei-xiong; Zhang, Zhi; Liang, Jie-hong

2008-04-01

To investigate the clinical value of T shape approach in the treatment of proximal tibial fractures. One handrend and thirteen patients of proximal tibial fractures were randomly divided into two groups. Group A: 62 cases underwent the traditional exposure approach. According to Schatzker classification,the cases of II to VI type was 25, 10, 16, 6, 5 respectively. Group B:51 cases underwent T shape approach ahead of knee joint, the cases of II to VI type was 21, 8, 13, 5, 4 respectively. All data were analyzed by SPSS 10.0 to compare operation time, blood loss, duration of hospitalization, healing time, the time of osseous union and complications after operation. Sixty patients in group A and 50 patients in group B were followed-up from 12 to 24 months. (1) Operation time:group B was longer than A (P time:group B was shorter. (4) Mean time of osseous union: 48 group B was shorter. Function of knee: group B was better than group A. (Complication: group B was less than group A. As compared with traditional exposure approach, T shape approach of knee joint had advantages of small scar, fewer complications, faster union of fracture and earlier recovery of joint function. The approach is valuable for the treatment of proximal tibial fractures.

Ultrasonography of the metacarpophalangeal and proximal interphalangeal joints in rheumatoid arthritis: a comparison with magnetic resonance imaging, conventional radiography and clinical examination

DEFF Research Database (Denmark)

Szkudlarek, Marcin; Klarlund, Mette; Narvestad, E.

2006-01-01

ultrasonography can provide information on signs of inflammation and destruction in RA finger joints that are not available with conventional radiography and clinical examination, and comparable to the information provided by magnetic resonance imaging (MRI). The second to fifth metacarpophalangeal and proximal...... interphalangeal joints of 40 RA patients and 20 control persons were assessed with ultrasonography, clinical examination, radiography and MRI. With MRI as the reference method, the sensitivity, specificity and accuracy of ultrasonography in detecting bone erosions in the finger joints were 0.59, 0.98 and 0...

Movement coordination patterns between the foot joints during walking

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John B. Arnold

2017-10-01

Full Text Available Abstract Background In 3D gait analysis, kinematics of the foot joints are usually reported via isolated time histories of joint rotations and no information is provided on the relationship between rotations at different joints. The aim of this study was to identify movement coordination patterns in the foot during walking by expanding an existing vector coding technique according to an established multi-segment foot and ankle model. A graphical representation is also described to summarise the coordination patterns of joint rotations across multiple patients. Methods Three-dimensional multi-segment foot kinematics were recorded in 13 adults during walking. A modified vector coding technique was used to identify coordination patterns between foot joints involving calcaneus, midfoot, metatarsus and hallux segments. According to the type and direction of joints rotations, these were classified as in-phase (same direction, anti-phase (opposite directions, proximal or distal joint dominant. Results In early stance, 51 to 75% of walking trials showed proximal-phase coordination between foot joints comprising the calcaneus, midfoot and metatarsus. In-phase coordination was more prominent in late stance, reflecting synergy in the simultaneous inversion occurring at multiple foot joints. Conversely, a distal-phase coordination pattern was identified for sagittal plane motion of the ankle relative to the midtarsal joint, highlighting the critical role of arch shortening to locomotor function in push-off. Conclusions This study has identified coordination patterns between movement of the calcaneus, midfoot, metatarsus and hallux by expanding an existing vector cording technique for assessing and classifying coordination patterns of foot joints rotations during walking. This approach provides a different perspective in the analysis of multi-segment foot kinematics, and may be used for the objective quantification of the alterations in foot joint

Effectiveness of adaptive silverware on range of motion of the hand

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Susan S. McDonald

2016-02-01

Full Text Available Background. Hand function is essential to a person’s self-efficacy and greatly affects quality of life. Adapted utensils with handles of increased diameters have historically been used to assist individuals with arthritis or other hand disabilities for feeding, and other related activities of daily living. To date, minimal research has examined the biomechanical effects of modified handles, or quantified the differences in ranges of motion (ROM when using a standard versus a modified handle. The aim of this study was to quantify the ranges of motion (ROM required for a healthy hand to use different adaptive spoons with electrogoniometry for the purpose of understanding the physiologic advantages that adapted spoons may provide patients with limited ROM. Methods. Hand measurements included the distal interphalangeal joint (DIP, proximal interphalangeal joint (PIP, and metacarpophalangeal joint (MCP for each finger and the interphalangeal (IP and MCP joint for the thumb. Participants were 34 females age 18–30 (mean age 20.38 ± 1.67 with no previous hand injuries or abnormalities. Participants grasped spoons with standard handles, and spoons with handle diameters of 3.18 cm (1.25 inch, and 4.45 cm (1.75 inch. ROM measurements were obtained with an electrogoniometer to record the angle at each joint for each of the spoon handle sizes. Results. A 3 × 3 × 4 repeated measures ANOVA (Spoon handle size by Joint by Finger found main effects on ROM of Joint (F(2, 33 = 318.68, Partial η2 = .95, p < .001, Spoon handle size (F(2, 33 = 598.73, Partial η2 = .97, p < .001, and Finger (F(3, 32 = 163.83, Partial η2 = .94, p < .001. As the spoon handle diameter size increased, the range of motion utilized to grasp the spoon handle decreased in all joints and all fingers (p < 0.01. Discussion. This study confirms the hypothesis that less range of motion is required to grip utensils with larger diameter handles, which in turn may reduce challenges for

Functional MRI of the patellofemoral joint: comparison of ultrafast MRI, motion-triggered cine MRI and static MRI

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Muhle, C. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Brossmann, J. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Melchert, U.H. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Schroeder, C. [Radiologische Abt., Universitaets-Kinderklinik, Christian-Albrechts-Universitaet, Kiel (Germany); Boer, R. de [Philips Medical Systems, Best (Netherlands); Spielmann, R.P. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik, Univ. Kiel (Germany)

1995-12-31

To evaluate the feasibility and usefulness of ultrafast MRI (u), patellar tracking from 30 of flexion to knee extension (0 ) was analysed and compared with motion-triggered cine MRI (m) and a static MRI technique (s). The different imaging methods were compared in respect of the patellofemoral relationship, the examination time and image quality. Eight healthy subjects and four patients (in total 18 joints) with patellar subluxation or luxation were examined. Significant differences between the static MRI series without quadriceps contraction and the functional MRI studies (motion-triggered cine MRI and ultrafast MRI) were found for the patellar tilt angle. In the dynamic joint studies there was no statistical difference of the regression coefficients between the motion-triggered cine MRI studies and the ultrafast MRI studies. The findings of the functional MRI studies compared with the static MRI images were significantly different for the lateralisation of the patella, expressed by the lateral patellar displacement and bisect offset. No significant differences in patellar lateralisation were found between motion-triggered cine MRI and ultrafast MRI. Ultrafast MRI was superior to motion-triggered cine MRI in terms of the reduction in imaging time and improvement of the image quality. (orig.)

Functional MRI of the patellofemoral joint: comparison of ultrafast MRI, motion-triggered cine MRI and static MRI

International Nuclear Information System (INIS)

Muhle, C.; Brossmann, J.; Melchert, U.H.; Schroeder, C.; Boer, R. de; Spielmann, R.P.; Heller, M.

1995-01-01

To evaluate the feasibility and usefulness of ultrafast MRI (u), patellar tracking from 30 of flexion to knee extension (0 ) was analysed and compared with motion-triggered cine MRI (m) and a static MRI technique (s). The different imaging methods were compared in respect of the patellofemoral relationship, the examination time and image quality. Eight healthy subjects and four patients (in total 18 joints) with patellar subluxation or luxation were examined. Significant differences between the static MRI series without quadriceps contraction and the functional MRI studies (motion-triggered cine MRI and ultrafast MRI) were found for the patellar tilt angle. In the dynamic joint studies there was no statistical difference of the regression coefficients between the motion-triggered cine MRI studies and the ultrafast MRI studies. The findings of the functional MRI studies compared with the static MRI images were significantly different for the lateralisation of the patella, expressed by the lateral patellar displacement and bisect offset. No significant differences in patellar lateralisation were found between motion-triggered cine MRI and ultrafast MRI. Ultrafast MRI was superior to motion-triggered cine MRI in terms of the reduction in imaging time and improvement of the image quality. (orig.)

Reliability of lower leg proximal end and forefoot kinematics during different paces of barefoot racewalking on a treadmill using a motion recorder (MVP-RF8-BC).

Science.gov (United States)

Wang, Hongzhao; Huo, Ming; An, Xiangde; Li, Yong; Onoda, Ko; Li, Desheng; Huang, Qiuchen; Maruyama, Hitoshi

2016-04-01

[Purpose] This study was performed to investigate the changes in lower leg proximal end and forefoot kinematics, and reliability of measurement during different paces of barefoot racewalking on treadmill. [Subjects] Eleven junior racewalking men participated in this study. [Methods] To identify changes in lower leg proximal end and forefoot kinematics, during different paces of barefoot racewalking on a treadmill, a wireless motion recorder (MVP-RF8-BC) was used. Interclass correlation coefficients (ICC 1, 2) were used to estimate reliability. [Results] There were significant differences in the lower leg proximal end and forefoot maximum medial/lateral rotations at a pace of 9 km/h compared with those at a pace of 5 km/h pace. The intra-examiner reliability estimates ranged from 0.82 and 0.89 to 0.87 and 0.93 for lower leg proximal end inversion/eversion rotation and medial/lateral rotation, and from 0.92 and 0.84 to 0.93 and 0.91 for forefoot inversion/eversion rotation and medial/lateral rotation. [Conclusion] We conclude that the lower leg proximal end and forefoot kinematics of barefoot racewalking on a treadmill are influenced by different paces and that assessment of lower leg proximal end and forefoot kinematics by means of the wireless motion recorder (MVP-RF8-BC) is adequately reliable. This information may be useful for determining exercise prescriptions.

4-corner arthrodesis and proximal row carpectomy: a biomechanical comparison of wrist motion and tendon forces.

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Debottis, Daniel P; Werner, Frederick W; Sutton, Levi G; Harley, Brian J

2013-05-01

Controversy exists as to whether a proximal row carpectomy (PRC) is a better procedure than scaphoid excision with 4-corner arthrodesis for preserving motion in the painful posttraumatic arthritic wrist. The purpose of this study was to determine how the kinematics and tendon forces of the wrist are altered after PRC and 4-corner arthrodesis. We tested 6 fresh cadaver forearms for the extremes of wrist motion and then used a wrist simulator to move them through 4 cyclic dynamic wrist motions, during which time we continuously recorded the tendon forces. We repeated the extremes of wrist motion measurements and the dynamic motions after scaphoid excision with 4-corner arthrodesis, and then again after PRC. We analyzed extremes of wrist motion and the peak tendon forces required for each dynamic motion using a repeated measures analysis of variance. Wrist extremes of motion significantly decreased after both the PRC and 4-corner arthrodesis compared with the intact wrist. Wrist flexion decreased on average 13° after 4-corner arthrodesis and 12° after PRC. Extension decreased 20° after 4-corner arthrodesis and 12° after PRC. Four-corner arthrodesis significantly decreased wrist ulnar deviation from the intact wrist. Four-corner arthrodesis allowed more radial deviation but less ulnar deviation than the PRC. The average peak tendon force was significantly greater after 4-corner arthrodesis than after PRC for the extensor carpi ulnaris during wrist flexion-extension, circumduction, and dart throw motions. The peak forces were significantly greater after 4-corner arthrodesis than in the intact wrist for the extensor carpi ulnaris during the dart throw motion and for the flexor carpi ulnaris during the circumduction motion. The peak extensor carpi radialis brevis force after PRC was significantly less than in the intact wrist. The measured wrist extremes of motion decreased after both 4-corner arthrodesis and PRC. Larger peak tendon forces were required to achieve

Cinematic study of temporomandibular joint motion using ultra-fast magnetic resonance imaging.

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Manière-Ezvan, A; Havet, T; Franconi, J M; Quémar, J C; de Certaines, J D

1999-10-01

Magnetic Resonance Images (MRI) of the temporomandibular joint (TMJ) are usually performed to study the opening/closing movements of the mandible and have up to now been pseudodynamic step-by-step images simulating condylar motion by post-processing reconstruction. The aim of this study was: 1. to optimize a TMJ cine-imaging method to give a better clinical result than the step-by-step methods; 2. to develop an ultra-fast MRI Gradient Echo (GE) sequence for this purpose; and 3. to analyze condylar movements in the sagittal, coronal and para-axial planes during border mandibular displacements and chewing. Both TM joints were studied in six asymptomatic volunteers. The method involved a compromise between in-plane resolution, slice thickness, signal-to-noise ratio and time resolution. Routine clinical use was found to be a GE pulse sequence providing three images per second with an isometric voxel resolution of approximately two millimeters in ridge. This did not allow visualization of the disk. Using this sequence enabled real and simultaneous condylar displacement observation in the three planes of space and therefore contributed to a better functional diagnosis of pathologic TMJ motions.

Change in the collateral and accessory collateral ligament lengths of the proximal interphalangeal joint using cadaveric model three-dimensional laser scanning.

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Sandhu, S S; Dreckmann, S; Binhammer, P A

2016-05-01

The purpose of this study was to assess the lengths of the index and middle finger proximal interphalangeal joint ligaments and determine the relative changes in the collateral and accessory collateral ligament lengths at 0°, 45° and 90° flexion. We generated three-dimensional scans of 16 finger (eight index and eight middle) proximal interphalangeal joints to assess relative changes in ligament length. Significant changes were found between 45°-90° and 0°-90° for the ulnar collateral ligament of the index finger and both collateral ligaments of the middle finger between 45°-90° and 0°-90°. No significant changes in length were found for the radial collateral ligament of the index finger or the accessory collateral ligaments of the index and middle fingers. Overall, it was found that the collateral ligament length changed significantly, but there was no significant change in the accessory collateral ligaments. Therapeutic IV. © The Author(s) 2015.

Validity of an ankle joint motion and position sense measurement system and its application in healthy subjects and patients with ankle sprain.

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Lin, Chueh-Ho; Chiang, Shang-Lin; Lu, Liang-Hsuan; Wei, Shun-Hwa; Sung, Wen-Hsu

2016-07-01

Ankle motion and proprioception in multiple axis movements are crucial for daily activities. However, few studies have developed and used a multiple axis system for measuring ankle motion and proprioception. This study was designed to validate a novel ankle haptic interface system that measures the ankle range of motion (ROM) and joint position sense in multiple plane movements, investigating the proprioception deficits during joint position sense tasks for patients with ankle instability. Eleven healthy adults (mean ± standard deviation; age, 24.7 ± 1.9 years) and thirteen patients with ankle instability were recruited in this study. All subjects were asked to perform tests to evaluate the validity of the ankle ROM measurements and underwent tests for validating the joint position sense measurements conducted during multiple axis movements of the ankle joint. Pearson correlation was used for validating the angular position measurements obtained using the developed system; the independent t test was used to investigate the differences in joint position sense task performance for people with or without ankle instability. The ROM measurements of the device were linearly correlated with the criterion standards (r = 0.99). The ankle instability and healthy groups were significantly different in direction, absolute, and variable errors of plantar flexion, dorsiflexion, inversion, and eversion (p ankle joint motion and position sense measurement system is valid and can be used for measuring the ankle ROM and joint position sense in multiple planes and indicate proprioception deficits for people with ankle instability. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Angular stable plates in proximal meta-epiphyseal tibial fractures: study of joint restoration and clinical and functional evaluation.

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Giannotti, S; Giovannelli, D; Dell'Osso, G; Bottai, V; Bugelli, G; Celli, F; Citarelli, C; Guido, G

2016-04-01

The tibial plateau fractures involve one of the main weight bearing joints of the human body. The goals of surgical treatment are anatomical reduction, articular surface reconstruction and high primary stability. The aim of this study was to evaluate the clinical and functional outcomes after internal plate fixation of this kind of fractures. From January 2009 to December 2012, we treated 75 cases of tibial plateau fracture with angular stable plates. We used Rasmussen Score and the Knee Society Score for the clinical and functional evaluation. Twenty-five cases that underwent hardware removal had arthroscopic and CT evaluation of the joint. No complications occurred. The clinical and functional evaluation, performed by the KSS and Rasmussen Score, highlighted the high percentage of good-to-excellent results (over 90 %). In every case, the range of motion was good with flexion >90°. Arthroscopy showed the presence of chondral damage in 100 % of patients. In all the cases, we found that X-ray images seem better than the CT images. Angular stable plates allow to obtain a good primary stability, permitting an early joint recovery with an excellent range of motion. Avoiding to perform a knee arthrotomy at the time of fracture reduction could prove to be an advantage in terms of functional recovery. The meniscus on the injured bone should be preserved in order to maintain good function of the joint. X-ray images remain the gold standard in checking the progression of post-traumatic osteoarthritis.

Use of a Multivector Mandibular Distractor for Treatment of Pediatric Proximal Interphalangeal Joint Pilon Fractures: A Case-Based Review.

Science.gov (United States)

Pedreira, Rachel; Cho, Brian H; Geer, Angela; DeJesus, Ramon A

2018-04-01

The difficulties in surgical treatment of pilon fractures of the finger include fragment reconstitution and posthealing stiffness. In adults, external fixation with traction and early active range of motion (AROM)/passive range of motion (PROM) during healing is considered necessary for avoiding joint stiffness and attaining realignment. The authors present a unique approach to pediatric pilon fractures that uses open reduction and multivector external fixation with delayed AROM/PROM. Initial immobilization and significant traction allowed for joint realignment and prevented noncompliance with staged distraction. The authors believe this immobilization leads to a superior outcome because, unlike adults, children tend to avoid stiffness and a larger distraction force allowed for sufficient joint realignment to regain range of motion (ROM). A right-handed 13-year-old boy sustained a right ring finger fracture and presented 12 days later. Radiographs revealed a comminuted Salter-Harris 4 fracture of the middle phalanx. The patient underwent open reduction and placement of multivector external fixation using a pediatric mandibular distractor/fixator. Significant traction was applied to distract the finger to length. Hardware was removed 6 weeks postoperatively and AROM was initiated after splinting. The patient started PROM 8 weeks postoperatively. Strengthening was initiated 2 weeks later. ROM improved and rehabilitation was continued. The patient exhibited nearly equal grip strength 12 weeks postoperatively. At 14 months follow-up, radiographs showed complete healing and joint realignment. There was no deformity or pain and finger length was restored. Management of pediatric pilon fractures is rarely described and presents unique considerations. Early-stage traction and immobilization using a multivector mandibular fixator/distractor is suitable in a child because noncompliance is avoided and there is a decreased risk for stiffness. Combining early immobilization

Association of knee confidence with pain, knee instability, muscle strength, and dynamic varus-valgus joint motion in knee osteoarthritis.

Science.gov (United States)

Skou, Søren T; Wrigley, Tim V; Metcalf, Ben R; Hinman, Rana S; Bennell, Kim L

2014-05-01

To investigate associations between self-reported knee confidence and pain, self-reported knee instability, muscle strength, and dynamic varus-valgus joint motion during walking. We performed a cross-sectional analysis of baseline data from 100 participants with symptomatic and radiographic medial tibiofemoral compartment osteoarthritis (OA) and varus malalignment recruited for a randomized controlled trial. The extent of knee confidence, assessed using a 5-point Likert scale item from the Knee Injury and Osteoarthritis Outcome Score, was set as the dependent variable in univariable and multivariable ordinal regression, with pain during walking, self-reported knee instability, quadriceps strength, and dynamic varus-valgus joint motion during walking as independent variables. One percent of the participants were not troubled with lack of knee confidence, 17% were mildly troubled, 50% were moderately troubled, 26% were severely troubled, and 6% were extremely troubled. Significant associations were found between worse knee confidence and higher pain intensity, worse self-reported knee instability, lower quadriceps strength, and greater dynamic varus-valgus joint motion. The multivariable model consisting of the same variables significantly accounted for 24% of the variance in knee confidence (P knee confidence is associated with higher pain, worse self-reported knee instability, lower quadriceps muscle strength, and greater dynamic varus-valgus joint motion during walking. Since previous research has shown that worse knee confidence is predictive of functional decline in knee OA, addressing lack of knee confidence by treating these modifiable impairments could represent a new therapeutic target. Copyright © 2014 by the American College of Rheumatology.

Assessment of Relationships Between Joint Motion Quality and Postural Control in Patients With Chronic Ankle Joint Instability.

Science.gov (United States)

Bączkowicz, Dawid; Falkowski, Krzysztof; Majorczyk, Edyta

2017-08-01

Study Design Controlled laboratory study, cross-sectional. Background Lateral ankle sprains are among the most common injuries encountered during athletic participation. Following the initial injury, there is an alarmingly high risk of reinjury and development of chronic ankle instability (CAI), which is dependent on a combination of factors, including sensorimotor deficits and changes in the biomechanical environment of the ankle joint. Objective To evaluate CAI-related disturbances in arthrokinematic motion quality and postural control and the relationships between them. Methods Sixty-three male subjects (31 with CAI and 32 healthy controls) were enrolled in the study. For arthrokinematic motion quality analysis, the vibroarthrographic signals were collected during ankle flexion/extension motion using an acceleration sensor and described by variability (variance of mean squares [VMS]), amplitude (mean of 4 maximal and 4 minimal values [R4]), and frequency (vibroarthrographic signal bands of 50 to 250 Hz [P1] and 250 to 450 Hz [P2]) parameters. Using the Biodex Balance System, single-leg dynamic balance was measured by overall, anteroposterior, and mediolateral stability indices. Results Values of vibroarthrographic parameters (VMS, R4, P1 and P2) were significantly higher in the CAI group than those in the control group (Pankle arthrokinematic motion and postural control were present. Therefore, physical therapy interventions focused on improving ankle neuromuscular control and arthrokinematic function are necessary in CAI patient care. J Orthop Sports Phys Ther 2017;47(8):570-577. Epub 4 Nov 2016. doi:10.2519/jospt.2017.6836.

Anatomic relationships of the distal and proximal radioulnar joints articulating surface areas, and of the radius and ulna bone volumes – implications for biomechanical studies of the distal and proximal radioulnar joints and forearm bones

Directory of Open Access Journals (Sweden)

Paul S C Malone

2016-07-01

Full Text Available BackgroundPrevious work from this laboratory has evidenced the biomechanical role of forearm osseoligamentous structures in load transfer of applied forces. It has shown that transmitted forces across the distal radioulnar joint (DRUJ and proximal radioulnar joint (PRUJ are similar though not identical under axial loading conditions. The purpose of the study was to assess the articulating surface areas of the radioulnar joints and the volumes of the forearm bones addressing the hypothesis that there may be anatomic adaptations that reflect the biomechanical function of the integrated forearm unit.MethodsThe articulating surface areas of PRUJ and DRUJ were assessed using a laser scanner in 24 cadaver forearms. The articulating joint surfaces were additionally delineated from standardized photographs assessed by three observers. The surface areas of matched pairs of joints were compared on the null hypothesis that these were the same within a given forearm specimen. An additional 44 pairs of matched forearm bone volumes were measured using water displacement technique and again compared through statistical analysis (paired sample t-test, and Bland Altman analysis.ResultsThe findings of this study are that the articulating surface areas of the DRUJ and PRUJ as well as the bone volumes are significantly different and yet strongly correlated. The paired sample t-test showed a significant difference between the surface areas of the DRUJ and PRUJ (p<0.05. The PRUJ articulating surface area was marginally larger than the DRUJ with a PRUJ : DRUJ ratio of 1.02. Paired sample t-test showed a significant difference between the two bone volumes (p<0.01 with a radius to ulna bone volume ratio of 0.81. When the olecranon was disregarded, radius volume was on average 4% greater than ulna volume.ConclusionsThis study demonstrated defines the anatomical relationships between the two forearm bones and their articulating joints when matched for specimen. The data

Muscle imbalance and reduced ankle joint motion in people with hammer toe deformity.

Science.gov (United States)

Kwon, O Y; Tuttle, L J; Johnson, J E; Mueller, M J

2009-10-01

Multiple factors may contribute to hammer toe deformity at the metatarsophalangeal joint. The purposes of this study were to (1) compare the ratio of toe extensor/flexor muscle strength in toes 2-4 among groups with and without hammer toe deformity, (2) to determine correlations between the ratio of toe extensor/flexor muscle strength in toes 2-4, and metatarsophalangeal joint deformity (3) to determine if other clinical measures differ between groups and if these measures are correlated with metatarsophalangeal joint angle. Twenty-seven feet with visible hammer toe deformity and 31 age matched feet without hammer toe deformity were tested. Toe muscle strength was measured using a dynamometer and the ratio of toe extensor muscle strength to flexor muscle strength was calculated. Metatarsophalangeal joint angle was measured from a computerized tomography image. Ankle and subtalar joint range of motion, and tibial torsion were measured using goniometry. Extensor/flexor toe muscle strength ratio was 2.3-3.0 times higher in the hammer toe group compared to the non-hammer toe group, in toes 2-4. The ratios of extensor/flexor toe muscle strength for toes 2-4 and metatarsophalangeal joint angle were highly correlated (r=0.69-0.80). Ankle dorsiflexion and metatarsophalangeal joint angle were negatively correlated for toes 2-4 (r=-0.38 to -0.56) as were eversion and metatarsophalangeal joint angle. These results provide insight into potential risk factors for the development of hammer toe deformity. Additional research is needed to determine the causal relationship between hammer toe deformity and the ratio of toe extensor/flexor muscle strength in toes 2-4.

Comparison of Lower Limb Segments Kinematics in a Taekwondo Kick. An Approach to the Proximal to Distal Motion

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Estevan Isaac

2015-09-01

Full Text Available In taekwondo, there is a lack of consensus about how the kick sequence occurs. The aim of this study was to analyse the peak velocity (resultant and value in each plane of lower limb segments (thigh, shank and foot, and the time to reach this peak velocity in the kicking lower limb during the execution of the roundhouse kick technique. Ten experienced taekwondo athletes (five males and five females; mean age of 25.3 ±5.1 years; mean experience of 12.9 ±5.3 years participated voluntarily in this study performing consecutive kicking trials to a target located at their sternum height. Measurements for the kinematic analysis were performed using two 3D force plates and an eight camera motion capture system. The results showed that the proximal segment reached a lower peak velocity (resultant and in each plane than distal segments (except the peak velocity in the frontal plane where the thigh and shank presented similar values, with the distal segment taking the longest to reach this peak velocity (p < 0.01. Also, at the instant every segment reached the peak velocity, the velocity of the distal segment was higher than the proximal one (p < 0.01. It provides evidence about the sequential movement of the kicking lower limb segments. In conclusion, during the roundhouse kick in taekwondo inter-segment motion seems to be based on a proximo-distal pattern.

[Partial replantation following proximal limb injury].

Science.gov (United States)

Dubert, T; Malikov, S A; Dinh, A; Kupatadze, D D; Oberlin, C; Alnot, J Y; Nabokov, B B

2000-11-01

Proximal replantation is a technically feasible but life-threatening procedure. Indications must be restricted to patients in good condition with a good functional prognosis. The goal of replantation must be focused not only on reimplanting the amputated limb but also on achieving a good functional outcome. For the lower limb, simple terminalization remains the best choice in many cases. When a proximal amputation is not suitable for replantation, the main aim of the surgical procedure must be to reconstruct a stump long enough to permit fitting a prosthesis preserving the function of the adjacent joint. If the proximal stump beyond the last joint is very short, it may be possible to restore some length by partial replantation of spared tissues from the amputated part. We present here the results we obtained following this policy. This series included 16 cases of partial replantations, 14 involving the lower limb and 2 the upper limb. All were osteocutaneous microsurgical transfers. For the lower limb, all transfers recovered protective sensitivity following tibial nerve repair. The functional calcaeoplantar unit was used in 13 cases. The transfer of this specialized weight bearing tissue provided a stable distal surface making higher support unnecessary. In one case, we raised a 13-cm vascularized tibial segment covered with foot skin for additional length. For the upper limb, the osteocutaneous transfer, based on the radial artery, was not reinnervated, but this lack of sensitivity did not impair prosthesis fitting. One vascular failure was finally amputated. This was the only unsuccessful result. For all other patients, the surgical procedure facilitated prosthesis fitting and preserved the proximal joint function despite an initially very proximal amputation. The advantages of partial replantation are obvious compared with simple terminalization or secondary reconstruction. There is no secondary donor site and, because there is no major muscle mass in the

Association between composites of selected motion palpation and pain provocation tests for sacroiliac joint disorders.

Science.gov (United States)

Soleimanifar, Manijeh; Karimi, Noureddin; Arab, Amir Massoud

2017-04-01

The sacroiliac joint (SIJ) has been implicated as a potential source of low back and buttock pain. Several types of motion palpation and pain provocation tests are used to evaluate SIJ dysfunction. The purpose of this study was to investigate the relationship between motion palpation and pain provocation tests in assessment of SIJ problems. This study is Descriptive Correlation. 50 patients between the ages of 20 and 65 participated. Four motion palpation tests (Sitting flexion, Standing flexion, Prone knee flexion, Gillet test) and three pain provocation tests (FABER, Posterior shear, Resisted abduction test) were examined. Chi-square analysis was used to assess the relationship between results of the individuals and composites of these two groups of tests. No significant relationship was found between these two groups of tests. It seems that motion palpation tests assess SIJ dysfunction and provocative tests assessed SIJ pain which do not appear to be related. Copyright © 2016 Elsevier Ltd. All rights reserved.

Chronic proliferative synovitis of the equine metacarpophalangeal joint

International Nuclear Information System (INIS)

Kannegieter, N.J.

1990-01-01

Chronic proliferative synovitis of 27 metacarpophalangeal joints in 16 horses is described. The diagnosis was based on a history of lameness and, or, poor performance, pain on flexion of the metacarpophalangeal joint, the response to intra-articular anaesthesia, and plain and contrast radiography. Radiographic findings included concavity of the distal dorsal metacarpus proximal to the sagittal ridge, and an increase in size of the synovial tissue adjacent to the proximal, dorsal attachment of the joint capsule. Mineralisation of the synovial tissue was present in some joints, and chip fractures from the dorsal aspect of the proximal phalanx were also occasionally seen. Treatment by arthroscopic resection of the tissue gave excellent results

Locking internal fixator with minimally invasive plate osteosynthesis for the proximal and distal tibial fractures

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TONG Da-ke

2012-02-01

Full Text Available 【Abstract】Objective: To investigate the efficacy of the locking internal fixator (LIF, which includes the locking compression plate (LCP and the less invasive stable system (LISS, in the proximal and distal tibial fractures. Methods: We did a retrospective study on a total of 98 patients with either proximal or distal tibial fractures from January 2003 to January 2007, who had received the opera- tion with LIF by the minimally invasive plate osteosynthesis (MIPO technique. The data consisted of 43 proximal tibial fractures (type AO41C3 and 55 distal tibial fractures (type AO43C3. Results: No complications were observed in all patients after operation. The mean healing time was 8.4 months (range 5-14 months. Only two cases of delayed union occurred at postoperative 10 months. No infections were reported after the definitive surgery even in the cases of open fractures. All patients reached a full range of motion at postoperative 6 to 9 months and regained the normal functions of knee and ankle joints. Conclusion: Using LIF in MIPO technique is a reliable approach towards the proximal and distal tibial fractures that are not suitable for intramedullary nailing. Key words: Internal fixator; Tibial fractures; Fracture fixation, intramedullary; Bone plates

Motion coordination affects movement parameters in a joint pick-and-place task

DEFF Research Database (Denmark)

Vesper, Cordula; Soutschek, Alexander; Schubö, Anna

2009-01-01

This study examined influences of social context on movement parameters in a pick-and-place task. Participants’ motion trajectories were recorded while they performed sequences of natural movements either working side-by-side with a partner or alone. It was expected that movement parameters would...... person performed the task while being observed by the partner. Results indicate that participants adapted their movements temporally and spatially to the joint action situation: Overall movement duration was shorter, and mean and maximum velocity was higher when actually working together than when...... action tasks....

Role and reliability of passive joint motion assessment: Towards multivariable diagnostics and decision-making in manual therapy

NARCIS (Netherlands)

van Trijffel, E.

2015-01-01

Manual therapists strongly rely on passive intervertebral motion (PIVM) assessment for making decisions about spinal joint mobilisation and thrust manipulation in patients with neck or low-back pain. However, uncertainty exists about the use and the value of this physical examination procedure

Human motion simulation predictive dynamics

CERN Document Server

Abdel-Malek, Karim

2013-01-01

Simulate realistic human motion in a virtual world with an optimization-based approach to motion prediction. With this approach, motion is governed by human performance measures, such as speed and energy, which act as objective functions to be optimized. Constraints on joint torques and angles are imposed quite easily. Predicting motion in this way allows one to use avatars to study how and why humans move the way they do, given specific scenarios. It also enables avatars to react to infinitely many scenarios with substantial autonomy. With this approach it is possible to predict dynamic motion without having to integrate equations of motion -- rather than solving equations of motion, this approach solves for a continuous time-dependent curve characterizing joint variables (also called joint profiles) for every degree of freedom. Introduces rigorous mathematical methods for digital human modelling and simulation Focuses on understanding and representing spatial relationships (3D) of biomechanics Develops an i...

Coracoclavicular joint

Energy Technology Data Exchange (ETDEWEB)

Kim, Kun Sang; Park, Chan Il; Ahn, Jae Doo; Lim, Chong Won [Seoul National University College of Medicine, Seoul (Korea, Republic of)

1970-10-15

The coracoclvicular joint, a rear abnormality which may be the cause of pain in the shoulder and limitation of motion of the shoulder joint, is discussed. A case of coracoclvicular joint with shoulder pain was observed in 65 yrs old Korean male.

Radiographic anatomy of soft tissue attachments in the equine metacarpophalangeal and proximal phalangeal region

International Nuclear Information System (INIS)

Weaver, J.C.B.; Stover, S.M.; O'Brien, T.R.

1992-01-01

The sites of bony attachment of the tendons, ligaments, and fibrous portion of the joint capsules of the equine metacarpophalangeal (fetlock) joint region were determined by gross dissection. These sites were transposed to standard radiographic views of the fetlock joint to yield illustrations that can be used as an aid in the diagnosis of soft tissue pathology from radiographs. Evidence of direct attachment of the common digital extensor tendon to the proximal phalanx was not found. Branches of the superficial digital flexor tendon were found to insert only on the middle phalanx. The recently described sites of insertion of the branches of the superficial digital flexor tendon to the proximal phalanx were found to be sites for attachment of the deep axial palmar ligaments of the proximal interphalangeal joint

[Range of Hip Joint Motion and Weight of Lower Limb Function under 3D Dynamic Marker].

Science.gov (United States)

Xia, Q; Zhang, M; Gao, D; Xia, W T

2017-12-01

To explore the range of reasonable weight coefficient of hip joint in lower limb function. When the hip joints of healthy volunteers under normal conditions or fixed at three different positions including functional, flexed and extension positions, the movements of lower limbs were recorded by LUKOtronic motion capture and analysis system. The degree of lower limb function loss was calculated using Fugl-Meyer lower limb function assessment form when the hip joints were fixed at the aforementioned positions. One-way analysis of variance and Tamhane's T2 method were used to proceed statistics analysis and calculate the range of reasonable weight coefficient of hip joint. There were significant differences between the degree of lower limb function loss when the hip joints fixed at flexed and extension positions and at functional position. While the differences between the degree of lower limb function loss when the hip joints fixed at flexed position and extension position had no statistical significance. In 95% confidence interval, the reasonable weight coefficient of hip joint in lower limb function was between 61.05% and 73.34%. Expect confirming the reasonable weight coefficient, the effects of functional and non-functional positions on the degree of lower limb function loss should also be considered for the assessment of hip joint function loss. Copyright© by the Editorial Department of Journal of Forensic Medicine

Proximal interphalangeal joint ankylosis in an early medieval horse from Wrocław Cathedral Island, Poland.

Science.gov (United States)

Janeczek, Maciej; Chrószcz, Aleksander; Onar, Vedat; Henklewski, Radomir; Skalec, Aleksandra

2017-06-01

Animal remains that are unearthed during archaeological excavations often provide useful information about socio-cultural context, including human habits, beliefs, and ancestral relationships. In this report, we present pathologically altered equine first and second phalanges from an 11th century specimen that was excavated at Wrocław Cathedral Island, Poland. The results of gross examination, radiography, and computed tomography, indicate osteoarthritis of the proximal interphalangeal joint, with partial ankylosis. Based on comparison with living modern horses undergoing lameness examination, as well as with recent literature, we conclude that the horse likely was lame for at least several months prior to death. The ability of this horse to work probably was reduced, but the degree of compromise during life cannot be stated precisely. Present day medical knowledge indicates that there was little likelihood of successful treatment for this condition during the middle ages. However, modern horses with similar pathology can function reasonably well with appropriate treatment and management, particularly following joint ankylosis. Thus, we approach the cultural question of why such an individual would have been maintained with limitations, for a probably-significant period of time. Copyright © 2017 Elsevier Inc. All rights reserved.

Employee customer orientation in manufacturing organizations: joint influences of customer proximity and the senior leadership team.

Science.gov (United States)

Liao, Hui; Subramony, Mahesh

2008-03-01

Pursuing a customer-focused strategy in manufacturing organizations requires employees across functions to embrace the importance of understanding customer needs and to align their everyday efforts with the goal of satisfying and retaining customers. Little prior research has examined what factors influence employee customer orientation in manufacturing settings. Drawing on the attraction-selection-attrition model, upper-echelons theory, and contingency theories of leadership, this study investigated the joint influences of functional roles' proximity to external customers and the senior leadership team's customer orientation on employee customer orientation. Hierarchical linear modeling results based on data obtained from 4,299 employees and 403 senior leaders from 42 facilities of a global manufacturer operating in 16 countries revealed that employees occupying customer-contact roles had the highest level of customer orientation, followed by employees occupying production roles, and then by those in support roles. In addition, there was a positive relationship between the senior leadership team's customer orientation and employee customer orientation for all 3 functional roles. The positive relationship between the senior leadership team and employee customer orientation was the strongest for employees in support roles, suggesting that lower levels of proximity to external customers may create a greater need for leadership in developing employees' customer-oriented attitudes. Copyright 2008 APA

Initial outcome and efficacy of S3 proximal humerus locking plate in the treatment of proximal humerus fractures

International Nuclear Information System (INIS)

Zhang Zhiming; Zhu Xuesong; Bao Zhaohua; Yang Huilin

2012-01-01

Objective: to explore the initial outcome and efficacy of S 3 proximal humerus locking plate in the treatment of proximal humerus fractures. Methods: Twenty-two patients with proximal humerus fracture were treated with the S 3 proximal humerus locking plate. Most of the fractures were complex, two-part (n=4), three-part (n=11) and four-part (n=7) fractures according to the Neer classification of the proximal humerus fractures. Results: All patients were followed up for 3∼15 months. There were no complications related to the implant including loosening or breakage of the plate. Good and excellent results were documented in 17 patients fair results in 4 patients according the Neer scores of shoulder. Conclusion: New design concepts of S 3 proximal humerus plate provide the subchondral support and the internal fixation support. With the addition of the proper exercise of the shoulder joint, the outcomes would be satisfied. (authors)

[Restricted motion after total knee arthroplasty].

Science.gov (United States)

Kucera, T; Urban, K; Karpas, K; Sponer, P

2007-10-01

The aim of the study was to ascertain what proportion of patients undergoing total knee arthroplasty (TKA) complain of restricted knee joint motion, and to investigate options for improvement of this situation. Our evaluation included a group of 796 patients treated with TKA at our department in the period from January 1, 1990, to December 31, 2004. In all cases, a condylar implant with preservation of the posterior cruciate ligaments was used. In addition to medical history, the range of motion, knee joint malalignment and radiological findings were assessed before surgery. After THA, the type of implant and complications, if any, were recorded, and improvement in joint motion was followed up. Based on the results of Kim et al., flexion contracture equal to or higher than 15 degrees and/or flexion less than 75 degrees were made the criteria of stiffness after THA. Patients with restricted THA motion who had aseptic or septic implant loosening were not included. Of the 796 evaluated patients, 32 (4.14 %) showed restricted motion after total knee arthroplasty, as assessed by the established criteria. In 16 patients, stiffness defined by these criteria had existed before surgery, and three patients showed an excessive production of adhesions and heterotopic ossifications. In three patients, the implantation procedure resulted in an elevated level of the original joint line and subsequent development of patella infera and increased tension of the posterior cruciate ligament. Four patients declined physical therapy and, in six, the main cause of stiffness could not be found. Seventeen patients did not require surgical therapy for restricted motion; TKA provided significant pain relief and they considered the range of motion achieved to be sufficient. One patient underwent redress 3 months after surgery, but with no success. Repeated releases of adhesions, replacement of a polyethylene liner and revision surgery of the extensor knee structures were performed in 15

Motion Analysis of Thumb in Cellular Phone Use

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Naotaka Sakai

2010-01-01

Full Text Available The thumb motion of 10 normal subjects during cellular phone use was measured using a reflective marker detection system to compare the maximum, minimum and range of flexion angles of the interphalangeal (IP, metacarpophalangeal (MP and carpometacarpal (CM joints. Two micro-reflective markers 3 mm in diameter were each placed on the dorsal surface of the distal phalanx, basal phalanx and metacarpal bone of the thumb. Three markers were placed on the dorsal hand in order to define the dorsal hand plane. Each subject pushed the 12 keys of a folding cellular phone with an 85-mm-long and 40-mm-wide keypad, sequentially from ‘1’ to ‘#’, and the pushing motion was recorded by six infrared video cameras for 12 seconds, using the VICON 612 system. The mean maximum flexion angle of the MP joint was significantly (p < .05 larger than the CM joint, and the mean minimum flexion angle of the CM joint was significantly (p < .01 smaller than the IP and MP joints. The mean range of motion of the IP joint was significantly (p < .05 larger than the MP and the CM joints. In a comparison of different key-pushing motions, only the CM joint was significantly (p < .05 larger in its range of motion. In conclusion, thumb motion on pushing the keys of the cellular phone was produced mainly by the MP and the CM joints. In addition, the ability to reach keys in different areas of the cellular phone keypad is regulated by changing the flexion angle of the CM joint.

Gender-related differences in lower limb alignment, range of joint motion, and the incidence of sports injuries in Japanese university athletes.

Science.gov (United States)

Mitani, Yasuhiro

2017-01-01

[Purpose] To investigate the gender-related differences in lower limb alignment, range of joint motion, and history of lower limb sports injuries in Japanese university athletes. [Subjects and Methods] The subjects were 224 Japanese university athletes (154 males and 70 females). The quadriceps angle (Q-angle), arch height index, and ranges of internal and external rotation of the hip joints were measured. History of lower limb sports injury was surveyed using a questionnaire. [Results] Females had a significantly higher Q-angle and hip joint internal rotation angle and a significantly lower arch height index than males. The survey revealed that a significantly higher proportion of females had a history of lower limb sports injuries, and that the proportion of those with a history of foot/ankle injuries was particularly high. [Conclusion] These results suggested that females experience more lower limb sports injuries than males, and that a large proportion of these injuries involve the foot/ankle. Reduced lower limb alignment and increased range of joint motion in females may be risk factors for injury because they lead to increased physical stress being exerted on the lower legs during sporting activities.

Customized Knee Prosthesis in Treatment of Giant Cell Tumors of the Proximal Tibia: Application of 3-Dimensional Printing Technology in Surgical Design.

Science.gov (United States)

Luo, Wenbin; Huang, Lanfeng; Liu, He; Qu, Wenrui; Zhao, Xin; Wang, Chenyu; Li, Chen; Yu, Tao; Han, Qing; Wang, Jincheng; Qin, Yanguo

2017-04-07

BACKGROUND We explored the application of 3-dimensional (3D) printing technology in treating giant cell tumors (GCT) of the proximal tibia. A tibia block was designed and produced through 3D printing technology. We expected that this 3D-printed block would fill the bone defect after en-bloc resection. Importantly, the block, combined with a standard knee joint prosthesis, provided attachments for collateral ligaments of the knee, which can maintain knee stability. MATERIAL AND METHODS A computed tomography (CT) scan was taken of both knee joints in 4 patients with GCT of the proximal tibia. We developed a novel technique - the real-size 3D-printed proximal tibia model - to design preoperative treatment plans. Hence, with the application of 3D printing technology, a customized proximal tibia block could be designed for each patient individually, which fixed the bone defect, combined with standard knee prosthesis. RESULTS In all 4 cases, the 3D-printed block fitted the bone defect precisely. The motion range of the affected knee was 90 degrees on average, and the soft tissue balance and stability of the knee were good. After an average 7-month follow-up, the MSTS score was 19 on average. No sign of prosthesis fracture, loosening, or other relevant complications were detected. CONCLUSIONS This technique can be used to treat GCT of the proximal tibia when it is hard to achieve soft tissue balance after tumor resection. 3D printing technology simplified the design and manufacturing progress of custom-made orthopedic medical instruments. This new surgical technique could be much more widely applied because of 3D printing technology.

Metacarpophalangeal joint synovial pad fibrotic proliferation in 63 horses

International Nuclear Information System (INIS)

Dabareiner, R.M.; White, N.A.; Sullins, K.E.

1996-01-01

Medical records, radiographs, and sonograms of 63 horses with metacarpophalangeal joint synovial pad proliferation were examined retrospectively. AR horses had lameness, joint effusion, or both signs associated with one or both metacarpophalangeal joints. Bony remodeling and concavity of the distodorsal aspect of the third metacarpal bone (Mc3) just proximal to the metacarpal condyles was identified by radiography in 71 joints (93%); 24 joints (32%) had radiographic evidence of a chip fracture located at the proximal dorsal aspect of the proximal phalanx. Fifty-four joints (71%) were examined by ultrasound. The mean +- SD sagittal thickness of the synovial pad was 11.3 +- 2.8 mm. Seventy-nine percent of the horses had single joint involvement with equal distribution between the right and left forelimbs. Sixty-eight joints in 55 horses were treated by arthroscopic surgery. Sixty joints (88%) had debridement of chondral or osteochondral fragmentation from the dorsal surface of Mc3 beneath the synovial pad and 30 joints (44%) had a bone chip fracture removed from the medial or lateral proximal dorsal eminence of the proximal phalanx. Complete or partial excision of both medial and lateral synovial pads was completed in 42 joints. Only the medial synovial pad was excised or trimmed in 21 joints, and 5 joints had only the lateral pad removed. Eight joints in eight horses were treated by stall rest, administration of intra-articular medication and systemic nonsteroidal anti-inflammatory drugs. Follow-up information was obtained for 50 horses treated surgically and for eight horses treated medically. Forty-three (86%) that had surgery returned to racing; 34 (68%) raced at an equivalent or better level than before surgery. Three (38%) of the medically treated horses returned to racing; only one horse raced better than the preinjury level. Horses that returned to racing at a similar or equal level of performance were significantly younger in age than horses returning at a

Individuality and togetherness in joint improvised motion.

Directory of Open Access Journals (Sweden)

Yuval Hart

Full Text Available Actors, dancers and musicians that improvise together report special moments of togetherness: high performance and synchrony, seemingly without a leader and a follower. Togetherness seems to conflict with individuality- the idiosyncratic character of each person's performance. To understand the relation of individuality and togetherness, we employed the mirror game paradigm in which two players are asked to mirror each other and create interesting synchronized motion, with and without a designated leader. The mirror game enables quantitative characterization of moments of togetherness in which complex motion is generated with high synchrony. We find that each person as a leader does basic strokes of motion with a characteristic signature, in terms of the shape of their velocity profile between two stopping events. In moments of togetherness both players change their signature to a universal stroke shape. This universal velocity profile resembles a half-period of a sine wave, and is therefore symmetric and maximally smooth. Thus, instead of converging to an intermediate motion signature, or having one player dominate, players seem to shift their basic motion signatures to a shape that is altogether different from their individually preferred shapes; the resulting motion may be easier to predict and to agree on. The players then build complex motion by using such smooth elementary strokes.

Individuality and togetherness in joint improvised motion.

Science.gov (United States)

Hart, Yuval; Noy, Lior; Feniger-Schaal, Rinat; Mayo, Avraham E; Alon, Uri

2014-01-01

Actors, dancers and musicians that improvise together report special moments of togetherness: high performance and synchrony, seemingly without a leader and a follower. Togetherness seems to conflict with individuality- the idiosyncratic character of each person's performance. To understand the relation of individuality and togetherness, we employed the mirror game paradigm in which two players are asked to mirror each other and create interesting synchronized motion, with and without a designated leader. The mirror game enables quantitative characterization of moments of togetherness in which complex motion is generated with high synchrony. We find that each person as a leader does basic strokes of motion with a characteristic signature, in terms of the shape of their velocity profile between two stopping events. In moments of togetherness both players change their signature to a universal stroke shape. This universal velocity profile resembles a half-period of a sine wave, and is therefore symmetric and maximally smooth. Thus, instead of converging to an intermediate motion signature, or having one player dominate, players seem to shift their basic motion signatures to a shape that is altogether different from their individually preferred shapes; the resulting motion may be easier to predict and to agree on. The players then build complex motion by using such smooth elementary strokes.

Proximal tibiofibular dislocation: a case report and review of literature

NARCIS (Netherlands)

Nieuwe Weme, R. A.; Somford, M. P.; Schepers, T.

2014-01-01

An isolated dislocation of the proximal tibiofibular joint is uncommon. The mechanism of this injury is usually sports related. We present a case where initial X-rays did not show the tibiofibular joint dislocation conclusively. It was diagnosed after comparative bilateral AP X-rays of the knees

Modified technique of the treatment for proximal tibiofibular joint dislocation

Directory of Open Access Journals (Sweden)

Gvozdenović Nemanja

2017-01-01

Full Text Available Introduction. Dislocation of the proximal tibiofibular joint (PTFJ is a rare injury. The diagnosis requires an accurate history of the mechanism and symptoms of the injury, and adequate clinical and radiographic evaluation of both knees. In the literature there is no larger series, only several cases of PTFJ dislocation treated by different methods have been published so far. The aim of the study was to present a modified technique for the treatment of the unstable PTFJ that results in faster recovery of the patient. Case report. A 24-year-old football player was injured at the beginning of training; when tackling the ball he felt a sharp pain in his right knee. He was immediately brought to the Emergency Center of Vojvodina and diagnosed with anterolateral dislocation of the PTFJ. Close reduction in general anesthesia was tried but we failed and then open reduction and internal fixation (ORIF were performed with a single three cortical screw. We preferred not to immobilise the knee after the procedure and immediately employed passive and active exercises in the knee, without bearing weight to the injured leg. After 6 weeks we removed the screw and gave full weight support to the leg and continued physical treatment. Conclusion. In case of acute PTFJ dislocation, the first method of choice is closed reduction in sedation or general anesthesia. If closed reduction fails, ORIF must be performed. ORIF without immobilization and early start of physical therapy lead to the rapid return to sports activities

Anatomical Evaluation of the Proximity of Neurovascular Structures During Arthroscopically Assisted Acromioclavicular Joint Reconstruction: A Cadaveric Pilot Study.

Science.gov (United States)

Banaszek, Daniel; Pickell, Michael; Wilson, Evan; Ducsharm, Melissa; Hesse, Daniel; Easteal, Ron; Bardana, Davide D

2017-01-01

The purpose of this study was to examine the safety of an arthroscopic technique for acromioclavicular joint (ACJ) reconstruction by investigating its proximity to important neurovascular structures. Six shoulders from 4 cadaveric specimens were used for ACJ reconstruction in this study. The procedure consists of performing an arthroscopic acromioclavicular (AC) reduction with a double button construct, followed by coracoclavicular ligament reconstruction without drilling clavicular tunnels. Shoulders were subsequently dissected in order to identify and measure distances to adjacent neurovascular structures. The suprascapular artery and nerve were the closest neurovascular structures to implanted materials. The mean distances were 8.2 (standard deviation [SD] = 3.6) mm to the suprascapular nerve and 5.6 (SD = 4.2) mm to the suprascapular artery. The mean distance of the suprascapular nerve from implants was found to be greater than 5 mm (P = .040), while the distance to the suprascapular artery was not (P > .5). Neither difference was statistically significant (P = .80 for artery; P = .08 for nerve). Mini-open, arthroscopically assisted ACJ reconstruction safely avoids the surrounding nerves, with no observed damage to any neurovascular structures including the suprascapular nerve and artery, and may be a viable alternative to open techniques. However, surgeons must remain cognizant of possible close proximity to the suprascapular artery. This study represents an evaluation of the safety and feasibility of a minimally invasive ACJ reconstruction as it relates to the proximity of neurovascular structures. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Modelling of the Human Knee Joint Supported by Active Orthosis

Science.gov (United States)

Musalimov, V.; Monahov, Y.; Tamre, M.; Rõbak, D.; Sivitski, A.; Aryassov, G.; Penkov, I.

2018-02-01

The article discusses motion of a healthy knee joint in the sagittal plane and motion of an injured knee joint supported by an active orthosis. A kinematic scheme of a mechanism for the simulation of a knee joint motion is developed and motion of healthy and injured knee joints are modelled in Matlab. Angles between links, which simulate the femur and tibia are controlled by Simulink block of Model predictive control (MPC). The results of simulation have been compared with several samples of real motion of the human knee joint obtained from motion capture systems. On the basis of these analyses and also of the analysis of the forces in human lower limbs created at motion, an active smart orthosis is developed. The orthosis design was optimized to achieve an energy saving system with sufficient anatomy, necessary reliability, easy exploitation and low cost. With the orthosis it is possible to unload the knee joint, and also partially or fully compensate muscle forces required for the bending of the lower limb.

Modelling of the Human Knee Joint Supported by Active Orthosis

Directory of Open Access Journals (Sweden)

Musalimov V.

2018-02-01

Full Text Available The article discusses motion of a healthy knee joint in the sagittal plane and motion of an injured knee joint supported by an active orthosis. A kinematic scheme of a mechanism for the simulation of a knee joint motion is developed and motion of healthy and injured knee joints are modelled in Matlab. Angles between links, which simulate the femur and tibia are controlled by Simulink block of Model predictive control (MPC. The results of simulation have been compared with several samples of real motion of the human knee joint obtained from motion capture systems. On the basis of these analyses and also of the analysis of the forces in human lower limbs created at motion, an active smart orthosis is developed. The orthosis design was optimized to achieve an energy saving system with sufficient anatomy, necessary reliability, easy exploitation and low cost. With the orthosis it is possible to unload the knee joint, and also partially or fully compensate muscle forces required for the bending of the lower limb.

Joint Inversion of 1-Hz GPS Data and Strong Motion Records for the Rupture Process of the 2008 Iwate-Miyagi Nairiku Earthquake: Objectively Determining Relative Weighting

Science.gov (United States)

Wang, Z.; Kato, T.; Wang, Y.

2015-12-01

The spatiotemporal fault slip history of the 2008 Iwate-Miyagi Nairiku earthquake, Japan, is obtained by the joint inversion of 1-Hz GPS waveforms and near-field strong motion records. 1-Hz GPS data from GEONET is processed by GAMIT/GLOBK and then a low-pass filter of 0.05 Hz is applied. The ground surface strong motion records from stations of K-NET and Kik-Net are band-pass filtered for the range of 0.05 ~ 0.3 Hz and integrated once to obtain velocity. The joint inversion exploits a broader frequency band for near-field ground motions, which provides excellent constraints for both the detailed slip history and slip distribution. A fully Bayesian inversion method is performed to simultaneously and objectively determine the rupture model, the unknown relative weighting of multiple data sets and the unknown smoothing hyperparameters. The preferred rupture model is stable for different choices of velocity structure model and station distribution, with maximum slip of ~ 8.0 m and seismic moment of 2.9 × 1019 Nm (Mw 6.9). By comparison with the single inversion of strong motion records, the cumulative slip distribution of joint inversion shows sparser slip distribution with two slip asperities. One common slip asperity extends from the hypocenter southeastward to the ground surface of breakage; another slip asperity, which is unique for joint inversion contributed by 1-Hz GPS waveforms, appears in the deep part of fault where very few aftershocks are occurring. The differential moment rate function of joint and single inversions obviously indicates that rich high frequency waves are radiated in the first three seconds but few low frequency waves.

Difference in Success Treating Proximal Interphalangeal and Metacarpophalangeal Joints with Collagenase

DEFF Research Database (Denmark)

Liv Hansen, Karina; Werlinrud, Jens Christian; Larsen, Søren

2017-01-01

with DD presenting with an extension deficit greater than 20° affecting the MP or PIP joint. RESULTS: We found a mean reduction in extension deficit of 47° (91%) for MP joints and 47° (76%) for PIP joints. Full correction (max 5° deficit) was achieved in 76% of MP and 28% of PIP joints. Skin rupture...... was seen in 34% of treatments. The 1-year relapse rate was 15% for MP and 67% for PIP joints. The reduction in quickDASH score was only statistically significant for MP joints at 1 year. Eighty-one percent of all patients reported being satisfied or very satisfied. No major adverse events were recorded...

A three-dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses.

Science.gov (United States)

Fatone, Stefania; Johnson, William Brett; Tucker, Kerice

2016-04-01

Misalignment of an articulated ankle-foot orthosis joint axis with the anatomic joint axis may lead to discomfort, alterations in gait, and tissue damage. Theoretical, two-dimensional models describe the consequences of misalignments, but cannot capture the three-dimensional behavior of ankle-foot orthosis use. The purpose of this project was to develop a model to describe the effects of ankle-foot orthosis ankle joint misalignment in three dimensions. Computational simulation. Three-dimensional scans of a leg and ankle-foot orthosis were incorporated into a link segment model where the ankle-foot orthosis joint axis could be misaligned with the anatomic ankle joint axis. The leg/ankle-foot orthosis interface was modeled as a network of nodes connected by springs to estimate interface pressure. Motion between the leg and ankle-foot orthosis was calculated as the ankle joint moved through a gait cycle. While the three-dimensional model corroborated predictions of the previously published two-dimensional model that misalignments in the anterior -posterior direction would result in greater relative motion compared to misalignments in the proximal -distal direction, it provided greater insight showing that misalignments have asymmetrical effects. The three-dimensional model has been incorporated into a freely available computer program to assist others in understanding the consequences of joint misalignments. Models and simulations can be used to gain insight into functioning of systems of interest. We have developed a three-dimensional model to assess the effect of ankle joint axis misalignments in ankle-foot orthoses. The model has been incorporated into a freely available computer program to assist understanding of trainees and others interested in orthotics. © The International Society for Prosthetics and Orthotics 2014.

Qualitative and quantitative descriptions of glenohumeral motion.

Science.gov (United States)

Hill, A M; Bull, A M J; Wallace, A L; Johnson, G R

2008-02-01

Joint modelling plays an important role in qualitative and quantitative descriptions of both normal and abnormal joints, as well as predicting outcomes of alterations to joints in orthopaedic practice and research. Contemporary efforts in modelling have focussed upon the major articulations of the lower limb. Well-constrained arthrokinematics can form the basis of manageable kinetic and dynamic mathematical predictions. In order to contain computation of shoulder complex modelling, glenohumeral joint representations in both limited and complete shoulder girdle models have undergone a generic simplification. As such, glenohumeral joint models are often based upon kinematic descriptions of inadequate degrees of freedom (DOF) for clinical purposes and applications. Qualitative descriptions of glenohumeral motion range from the parody of a hinge joint to the complex realism of a spatial joint. In developing a model, a clear idea of intention is required in order to achieve a required application. Clinical applicability of a model requires both descriptive and predictive output potentials, and as such, a high level of validation is required. Without sufficient appreciation of the clinical intention of the arthrokinematic foundation to a model, error is all too easily introduced. Mathematical description of joint motion serves to quantify all relevant clinical parameters. Commonly, both the Euler angle and helical (screw) axis methods have been applied to the glenohumeral joint, although concordance between these methods and classical anatomical appreciation of joint motion is limited, resulting in miscommunication between clinician and engineer. Compounding these inconsistencies in motion quantification is gimbal lock and sequence dependency.

Self-aligning exoskeleton hip joint: Kinematic design with five revolute, three prismatic and one ball joint.

Science.gov (United States)

Beil, Jonas; Marquardt, Charlotte; Asfour, Tamim

2017-07-01

Kinematic compatibility is of paramount importance in wearable robotic and exoskeleton design. Misalignments between exoskeletons and anatomical joints of the human body result in interaction forces which make wearing the exoskeleton uncomfortable and even dangerous for the human. In this paper we present a kinematically compatible design of an exoskeleton hip to reduce kinematic incompatibilities, so called macro- and micro-misalignments, between the human's and exoskeleton's joint axes, which are caused by inter-subject variability and articulation. The resulting design consists of five revolute, three prismatic and one ball joint. Design parameters such as range of motion and joint velocities are calculated based on the analysis of human motion data acquired by motion capture systems. We show that the resulting design is capable of self-aligning to the human hip joint in all three anatomical planes during operation and can be adapted along the dorsoventral and mediolateral axis prior to operation. Calculation of the forward kinematics and FEM-simulation considering kinematic and musculoskeletal constraints proved sufficient mobility and stiffness of the system regarding the range of motion, angular velocity and torque admissibility needed to provide 50 % assistance for an 80 kg person.

Pseudoarthrosis following proximal humeral fractures: A possible mechanism

Energy Technology Data Exchange (ETDEWEB)

Rooney, P.J.; Cockshott, W.P.

1986-01-01

A small series of four patients with pseudarthrosis of the proximal humeral shaft is reported. These patients all had restricted movement of the shoulder joint prior to the trauma, three as a result of rheumatoid arthritis and one due a surgical fusion of the glenohumeral joint. It is suggested that pseudarthrosis is more likely under these circumstances and that pursuit of union of the fracture in such patients may not always be necessary.

Phalangeal joints kinematics during ostrich (Struthio camelus locomotion

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Rui Zhang

2017-01-01

Full Text Available The ostrich is a highly cursorial bipedal land animal with a permanently elevated metatarsophalangeal joint supported by only two toes. Although locomotor kinematics in walking and running ostriches have been examined, these studies have been largely limited to above the metatarsophalangeal joint. In this study, kinematic data of all major toe joints were collected from gaits with double support (slow walking to running during stance period in a semi-natural setup with two selected cooperative ostriches. Statistical analyses were conducted to investigate the effect of locomotor gait on toe joint kinematics. The MTP3 and MTP4 joints exhibit the largest range of motion whereas the first phalangeal joint of the 4th toe shows the largest motion variability. The interphalangeal joints of the 3rd and 4th toes present very similar motion patterns over stance phases of slow walking and running. However, the motion patterns of the MTP3 and MTP4 joints and the vertical displacement of the metatarsophalangeal joint are significantly different during running and slow walking. Because of the biomechanical requirements, osctriches are likely to select the inverted pendulum gait at low speeds and the bouncing gait at high speeds to improve movement performance and energy economy. Interestingly, the motions of the MTP3 and MTP4 joints are highly synchronized from slow to fast locomotion. This strongly suggests that the 3rd and 4th toes really work as an “integrated system” with the 3rd toe as the main load bearing element whilst the 4th toe as the complementary load sharing element with a primary role to ensure the lateral stability of the permanently elevated metatarsophalangeal joint.

Protocol optimization of sacroiliac joint MR Imaging at 3 Tesla: Impact of coil design and motion resistant sequences on image quality.

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Gondim Teixeira, P A; Bravetti, M; Hossu, G; Lecocq, S; Petit, D; Loeuille, D; Blum, A

2017-12-01

To evaluate the impact of coil design and motion-resistant sequences on the quality of sacroiliac magnetic resonance imaging (MRI) examination in patients with spondyloarthropathy. One hundred and twenty-one patients with suspected sacroiliitis and referred for MRI of the sacroiliac joints were retrospectively evaluated with MRI at 3-Tesla. There were 78 women and 43 men with a mean age of 36.7±11.5 (SD) years (range: 15.8-78.4 years). Conventional and motion-resistant fat-saturated fast-spin echo T2-weighted sequences were performed with two different coils. Image quality was subjectively evaluated by two independent readers (R1 and R2) using a four-point scale. Confidence in the identification of bone marrow edema pattern (BMEP) was also evaluated subjectively using a three-point scale. Phased array body coil yielded improved image quality compared to surface coil (14.1 to 30.4% for R1 and 14.6 to 25.7% for R2; Pcoil with motion-resistant T2-weighted sequence (kappa 0.990). The smallest number of indeterminate BMEP zones was seen on MRI set acquired with the phased-array body coil and motion-resistant T2-weighted sequence. Phased array body coil and motion-resistant T2-weighted sequences perform better than surface coil and conventional T2-weighted sequences for the evaluation of sacroiliac joints, increasing confidence in the identification of BMEP. Copyright © 2017 Editions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Smartphone and Universal Goniometer for Measurement of Elbow Joint Motions: A Comparative Study

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Behnoush, Behnam; Tavakoli, Nasim; Bazmi, Elham; Nateghi Fard, Fariborz; Pourgharib Shahi, Mohammad Hossein; Okazi, Arash; Mokhtari, Tahmineh

2016-01-01

Background Universal goniometer (UG) is commonly used as a standard method to evaluate range of motion (ROM) as part of joint motions. It has some restrictions, such as involvement of both hands of the physician, leads to instability of hands and error. Nowadays smartphones usage has been increasing due to its easy application. Objectives The study was designed to compare the smartphone inclinometer-based app and UG in evaluation of ROM of elbow. Materials and Methods The maximum ROM of elbow in position of flexion and pronation and supination of forearm were examined in 60 healthy volunteers with UG and smartphone. Data were analyzed using SPSS (ver. 16) software and appropriate statistical tests were applied, such as paired t-test, ICC and Bland Altman curves. Results The results of this study showed high reliability and validity of smartphone in regarding UG with ICC > 0.95. The highest reliability for both methods was in elbow supination and the lowest was in the elbow flexion (0.84). Conclusions Smartphones due to ease of access and usage for the physician and the patient, may be good alternatives for UG. PMID:27625754

The plantar plate of the first metatarsophalangeal joint: an anatomical study.

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Lucas, Douglas E; Philbin, Terrence; Hatic, Safet

2014-04-01

The plantar plate of the first metatarsophalangeal (MP) joint is a critical structure of the forefoot that has been identified as a major stabilizer within the capsuloligamentous complex. Many studies have clarified and documented the anatomy of the lesser toe MP plantar plates, but few have looked closely at the anatomy of the first MP joint. Ten cadaveric specimens were examined to identify and document the objective anatomic relationship of the plantar plate, tibial sesamoid, and surrounding osseus structures. The average distance of the plantar plate distal insertion from the joint line into the proximal phalanx was 0.33 mm. The plantar plate was inserted into the metatarsal head on average 17.29 mm proximal from the joint line. The proximal aspect of the sesamoid was 18.55 mm proximal to the distal attachment of the plantar plate to the phalanx. The distal aspect of the sesamoid averaged 4.69 mm away from the distal attachment into the proximal phalanx. The footprint of the distal plate insertion was on average 6.33 mm in length in the sagittal plane. The authors hope that these objective data measures can aid in the understanding and subsequent surgical repair of this important forefoot structure.

Decreased Temporomandibular Joint Range of Motion in a Model of Early Osteoarthritis in the Rabbit

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Henderson, Sarah E.; Tudares, Mauro A.; Tashman, Scott; Almarza, Alejandro J.

2015-01-01

Purpose Analysis of mandibular biomechanics could help with understanding the mechanisms of temporomandibular joint (TMJ) disorders (TMJDs), such as osteoarthritis (TMJ-OA), by investigating the effects of injury or disease on TMJ movement. The objective of the present study was to determine the functional kinematic implications of mild TMJ-OA degeneration caused by altered occlusion from unilateral splints in the rabbit. Materials and Methods Altered occlusion of the TMJ was mechanically induced in rabbits by way of a unilateral molar dental splint (n = 3). TMJ motion was assessed using 3-dimensional (3D) skeletal kinematics twice, once before and once after 6 weeks of splint placement with the splints removed, after allowing 3 days of recovery. The relative motion of the condyle to the fossa and the distance between the incisors were tracked. Results An overall decrease in the range of joint movement was observed at the incisors and in the joint space between the condyle and fossa. The incisor movement decreased from 7.0 ± 0.5 mm to 6.2 ± 0.5 mm right to left, from 5.5 ± 2.2 mm to 4.6 ± 0.8 mm anterior to posterior, and from 13.3 ± 1.8 mm to 11.6 ± 1.4 mm superior to inferior (P < .05). The total magnitude of the maximum distance between the points on the condyle and fossa decreased from 3.6 ± 0.8 mm to 3.1 ± 0.6 mm for the working condyle and 2.8 ± 0.4 mm to 2.5 ± 0.4 mm for the balancing condyle (P < .05). The largest decreases were seen in the anteroposterior direction for both condyles. Conclusion Determining the changes in condylar movement might lead to a better understanding of the early predictors in the development of TMJ-OA and determining when the symptoms become a chronic, irreversible problem. PMID:25889371

Joint Intentionality

Directory of Open Access Journals (Sweden)

Koreň Ladislav

2016-03-01

Full Text Available According to the shared intentionality hypothesis proposed by Michael Tomasello, two cognitive upgrades – joint and collective intentionality, respectively – make human thinking unique. Joint intentionality, in particular, is a mindset supposed to account for our early, species-specific capacity to participate in collaborative activities involving two (or a few agents. In order to elucidate such activities and their proximate cognitive-motivational mechanism, Tomasello draws on philosophical accounts of shared intentionality. I argue that his deference to such cognitively demanding accounts of shared intentional activities is problematic if his theoretical ambition is in part to show that and how early (prelinguistic and precultural capacities for joint action contribute to the development of higher cognitive capacities.

Novel Treatment of a Scapholunate Ligament Injury with Proximal Pole Scaphoid Nonunion

Science.gov (United States)

Gaspar, Michael P.; Kane, Patrick M.; Jacoby, Sidney M.; Culp, Randall W.

2016-01-01

Background  Nonunion of scaphoid proximal pole fractures presents a challenging management dilemma to hand surgeons. This problem is further complicated in the uncommon concurrence of scapholunate (SL) ligament disruption. Case Description  A 39-year-old male patient presented with new-onset wrist pain following a remote history of a proximal pole scaphoid fracture sustained as a teenager, which was treated nonoperatively. Six months before presentation, the patient sustained a fall while snowboarding. The patient was found to have a chronic nonunion of his scaphoid proximal pole with an associated SL ligament disruption. As the proximal fragment was too small to be amenable to fixation, the patient was treated with an arthroscopic partial scaphoid excision and SL ligament reconstruction using a scapholunateintercarpal screw placed percutaneously. At 26 months, the patient exhibited no pain, near-normal strength, and wrist motion, and expressed a high-level of satisfaction from his surgery. Literature Review  Although cases of SL ligament disruption with concomitant proximal scaphoid fractures have been reported, to our knowledge, this is the first report of SL ligament rupture occurring in the setting of a preexisting proximal pole scaphoid nonunion. Clinical Relevance  We report the use of SL ligament reconstruction augmented with intercarpal screw fixation, and excision of the proximal pole scaphoid nonunion. This minimallyinvasive approach may be a particularly useful option in young, active patients such as our own, where a motion-sacrificing salvage procedure would be less than ideal. PMID:27616829

Compensating for intersegmental dynamics across the shoulder, elbow, and wrist joints during feedforward and feedback control.

Science.gov (United States)

Maeda, Rodrigo S; Cluff, Tyler; Gribble, Paul L; Pruszynski, J Andrew

2017-10-01

Moving the arm is complicated by mechanical interactions that arise between limb segments. Such intersegmental dynamics cause torques applied at one joint to produce movement at multiple joints, and in turn, the only way to create single joint movement is by applying torques at multiple joints. We investigated whether the nervous system accounts for intersegmental limb dynamics across the shoulder, elbow, and wrist joints during self-initiated planar reaching and when countering external mechanical perturbations. Our first experiment tested whether the timing and amplitude of shoulder muscle activity account for interaction torques produced during single-joint elbow movements from different elbow initial orientations and over a range of movement speeds. We found that shoulder muscle activity reliably preceded movement onset and elbow agonist activity, and was scaled to compensate for the magnitude of interaction torques arising because of forearm rotation. Our second experiment tested whether elbow muscles compensate for interaction torques introduced by single-joint wrist movements. We found that elbow muscle activity preceded movement onset and wrist agonist muscle activity, and thus the nervous system predicted interaction torques arising because of hand rotation. Our third and fourth experiments tested whether shoulder muscles compensate for interaction torques introduced by different hand orientations during self-initiated elbow movements and to counter mechanical perturbations that caused pure elbow motion. We found that the nervous system predicted the amplitude and direction of interaction torques, appropriately scaling the amplitude of shoulder muscle activity during self-initiated elbow movements and rapid feedback control. Taken together, our results demonstrate that the nervous system robustly accounts for intersegmental dynamics and that the process is similar across the proximal to distal musculature of the arm as well as between feedforward (i

Comparison of 3D Joint Angles Measured With the Kinect 2.0 Skeletal Tracker Versus a Marker-Based Motion Capture System.

Science.gov (United States)

Guess, Trent M; Razu, Swithin; Jahandar, Amirhossein; Skubic, Marjorie; Huo, Zhiyu

2017-04-01

The Microsoft Kinect is becoming a widely used tool for inexpensive, portable measurement of human motion, with the potential to support clinical assessments of performance and function. In this study, the relative osteokinematic Cardan joint angles of the hip and knee were calculated using the Kinect 2.0 skeletal tracker. The pelvis segments of the default skeletal model were reoriented and 3-dimensional joint angles were compared with a marker-based system during a drop vertical jump and a hip abduction motion. Good agreement between the Kinect and marker-based system were found for knee (correlation coefficient = 0.96, cycle RMS error = 11°, peak flexion difference = 3°) and hip (correlation coefficient = 0.97, cycle RMS = 12°, peak flexion difference = 12°) flexion during the landing phase of the drop vertical jump and for hip abduction/adduction (correlation coefficient = 0.99, cycle RMS error = 7°, peak flexion difference = 8°) during isolated hip motion. Nonsagittal hip and knee angles did not correlate well for the drop vertical jump. When limited to activities in the optimal capture volume and with simple modifications to the skeletal model, the Kinect 2.0 skeletal tracker can provide limited 3-dimensional kinematic information of the lower limbs that may be useful for functional movement assessment.

Helical axes of skeletal knee joint motion during running.

Science.gov (United States)

van den Bogert, A J; Reinschmidt, C; Lundberg, A

2008-01-01

The purpose of this study was to determine the changes in the axis of rotation of the knee that occur during the stance phase of running. Using intracortical pins, the three-dimensional skeletal kinematics of three subjects were measured during the stance phase of five running trials. The stance phase was divided into equal motion increments for which the position and orientation of the finite helical axes (FHA) were calculated relative to a tibial reference frame. Results were consistent within and between subjects. At the beginning of stance, the FHA was located at the midepicondylar point and during the flexion phase moved 20mm posteriorly and 10mm distally. At the time of peak flexion, the FHA shifted rapidly by about 10-20mm in proximal and posterior direction. The angle between the FHA and the tibial transverse plane increased gradually during flexion, to about 15 degrees of medial inclination, and then returned to zero at the start of the extension phase. These changes in position and orientation of FHA in the knee should be considered in analyses of muscle function during human movement, which require moment arms to be defined relative to a functional rotation axis. The finding that substantial changes in axis of rotation occurred independent of flexion angle suggests that musculoskeletal models must have more than one kinematic degree-of-freedom at the knee. The same applies to the design of knee prostheses, if the goal is to restore normal muscle function.

Open dislocation of the proximal interphalangeal joint of the little finger subsequent to chronic radial collateral ligament injury: a case report of primary ligament reconstruction with a half-slip of the flexor digitorum superficialis: Case Report.

Science.gov (United States)

Wada, Kazuma; Hibino, Naohito; Kondo, Kenji; Yoshioka, Shinji; Terai, Tomoya; Henmi, Tatsuhiko; Sairyo, Koichi

2015-01-01

Open dislocation of the proximal interphalangeal (PIP) joint is relatively rare. We report a case of a 32-year-old man who had open dislocation of the PIP joint of the little finger while playing American football. He had a history of chronic radial collateral ligament injury. We reconstructed the radial collateral ligament with a half-slip of the flexor digitorum superficialis tendon.

Fractures of the proximal humerus involving the intertubercular groove

International Nuclear Information System (INIS)

Ahovuo, J.; Paavolainen, P.; Bjoerkenheim, J.M.; Helsinki Univ. Central Hospital

1989-01-01

The purpose of this study was to analyse the involvement of the gliding surface of the biceps tendon in fractures of the proximal humerus. Fifteen patients had a fracture of the proximal humerus verified with antero-posterior and axillary radiographs. Tangential radiographs of the intertubercular groove, obtained from the shoulder joint, showed involvement of the intertubercular groove in 13 patients (87%), which could not be shown with other projections. Groove radiographs revealed in 3 patients a dislocation of the fragments of the greater tuberosity large enough to require surgical treatment, but which had not been found using conventional techniques. Therefore, a groove radiograph should be used to precise fractures of the proximal humerus. (orig.)

Programmable motion of DNA origami mechanisms.

Science.gov (United States)

Marras, Alexander E; Zhou, Lifeng; Su, Hai-Jun; Castro, Carlos E

2015-01-20

DNA origami enables the precise fabrication of nanoscale geometries. We demonstrate an approach to engineer complex and reversible motion of nanoscale DNA origami machine elements. We first design, fabricate, and characterize the mechanical behavior of flexible DNA origami rotational and linear joints that integrate stiff double-stranded DNA components and flexible single-stranded DNA components to constrain motion along a single degree of freedom and demonstrate the ability to tune the flexibility and range of motion. Multiple joints with simple 1D motion were then integrated into higher order mechanisms. One mechanism is a crank-slider that couples rotational and linear motion, and the other is a Bennett linkage that moves between a compacted bundle and an expanded frame configuration with a constrained 3D motion path. Finally, we demonstrate distributed actuation of the linkage using DNA input strands to achieve reversible conformational changes of the entire structure on ∼ minute timescales. Our results demonstrate programmable motion of 2D and 3D DNA origami mechanisms constructed following a macroscopic machine design approach.

Programmable motion of DNA origami mechanisms

Science.gov (United States)

Marras, Alexander E.; Zhou, Lifeng; Su, Hai-Jun; Castro, Carlos E.

2015-01-01

DNA origami enables the precise fabrication of nanoscale geometries. We demonstrate an approach to engineer complex and reversible motion of nanoscale DNA origami machine elements. We first design, fabricate, and characterize the mechanical behavior of flexible DNA origami rotational and linear joints that integrate stiff double-stranded DNA components and flexible single-stranded DNA components to constrain motion along a single degree of freedom and demonstrate the ability to tune the flexibility and range of motion. Multiple joints with simple 1D motion were then integrated into higher order mechanisms. One mechanism is a crank–slider that couples rotational and linear motion, and the other is a Bennett linkage that moves between a compacted bundle and an expanded frame configuration with a constrained 3D motion path. Finally, we demonstrate distributed actuation of the linkage using DNA input strands to achieve reversible conformational changes of the entire structure on ∼minute timescales. Our results demonstrate programmable motion of 2D and 3D DNA origami mechanisms constructed following a macroscopic machine design approach. PMID:25561550

Improper trunk rotation sequence is associated with increased maximal shoulder external rotation angle and shoulder joint force in high school baseball pitchers.

Science.gov (United States)

Oyama, Sakiko; Yu, Bing; Blackburn, J Troy; Padua, Darin A; Li, Li; Myers, Joseph B

2014-09-01

In a properly coordinated throwing motion, peak pelvic rotation velocity is reached before peak upper torso rotation velocity, so that angular momentum can be transferred effectively from the proximal (pelvis) to distal (upper torso) segment. However, the effects of trunk rotation sequence on pitching biomechanics and performance have not been investigated. The aim of this study was to investigate the effects of trunk rotation sequence on ball speed and on upper extremity biomechanics that are linked to injuries in high school baseball pitchers. The hypothesis was that pitchers with improper trunk rotation sequence would demonstrate lower ball velocity and greater stress to the joint. Descriptive laboratory study. Three-dimensional pitching kinematics data were captured from 72 high school pitchers. Subjects were considered to have proper or improper trunk rotation sequences when the peak pelvic rotation velocity was reached either before or after the peak upper torso rotation velocity beyond the margin of error (±3.7% of the time from stride-foot contact to ball release). Maximal shoulder external rotation angle, elbow extension angle at ball release, peak shoulder proximal force, shoulder internal rotation moment, and elbow varus moment were compared between groups using independent t tests (α ways that may influence injury risk. As such, exercises that reinforce the use of a proper trunk rotation sequence during the pitching motion may reduce the stress placed on the structures around the shoulder joint and lead to the prevention of injuries. © 2014 The Author(s).

Hip joint mobility in dancers: preliminary report.

Science.gov (United States)

Drężewska, Marlena; Gałuszka, Renata; Sliwiński, Zbigniew

2012-01-01

The aim of this study was to evaluate the impact of dancing on hip joint mobility and to assess the relationship between active movements of the hips and injuries among dancers, which may be important in planning rehabilitation in this group. The sample comprised 49 dancers (37 women and 12 men) aged 15 to 32 years. The participants were the professional dancers of the Kielce Dance Theatre and members of two youth jazz dance teams from the Kielce Dance Theatre. The active range of motion of the hips was measured in three planes using a goniometer in order to assess the influence of dance training on hip joint mobility. A questionnaire-based survey was also conducted. The range of flexion, extension and external rotation was significantly greater in the group of long-time dancers (p <0.05). There was a significantly greater range of flexion, abduction and external rotation in previously injured hip joints (p<0.05). 1. Injuries to hip joints in dancers may result in increased ranges of motion, which may lead to disturbances of joint stability. 2. Being a long-time dancer and the female gender were associated with an increased range of hip joint motion.

SINA: A test system for proximity fuses

Science.gov (United States)

Ruizenaar, M. G. A.

1989-04-01

SINA, a signal generator that can be used for testing proximity fuses, is described. The circuitry of proximity fuses is presented; the output signal of the RF circuit results from a mixing of the emitted signal and received signal that is Doppler shifted in frequency by the relative motion of the fuse with respect to the reflecting target of surface. With SINA, digitized and stored target and clutter signals (previously measured) can be transformed to Doppler signals, for example during a real flight. SINA can be used for testing fuse circuitry, for example in the verification of results of computer simulations of the low frequency Doppler signal processing. The software of SINA and its use are explained.

Functional MR imaging of the patellofemoral joint

International Nuclear Information System (INIS)

Muhle, C.; Brossmann, J.; Heller, M.

1995-01-01

Conventional X-ray examinations of the patellofemoral joint in 30 , 60 and 90 of knee flexion demonstrate the position of the patella. On the other hand, they have been shown to be insufficient for the diagnosis of patellofemoral maltracking in the critical range between 30 of flexion and full extension. Motion-triggered and ultrafast MRI offer new possibilities for functional diagnosis of the patellofemoral joint under active knee motion. Functional MRI of the patellofemoral joint is suggested as an alternative to arthroscopy, particularly in patients with anterior knee pain or suspected patellar maltracking. (orig.) [de

Arthroscopy of the fetlock joint of the dromedary camel.

Science.gov (United States)

Ali, M M; Abd-Elnaeim, M

2012-01-01

To describe a technique for arthroscopy of the fetlock joint of the dromedary camel, and the problems that could occur during and after arthroscopy. Seven animals (4 cadaveric limbs and 3 living camels) were used in this study. Two dorsal arthroscopic portals (lateral and medial) and one palmaro-lateral portal were used. Distension of the joint capsule was effected by injecting Ringer´s lactate solution into the joint cavity. Landmarks for the dorsal arthroscopic portals were located at the centre of the groove bounded by the lateral branch of the suspensory ligament and the large metacarpus at a point 1 cm proximal to the joint. The palmaro-lateral portal was located in a triangular area between the branch of the suspensory ligament, the large metacarpus, and the sesamoid bone, with insertion of the arthroscope in a 45° joint flexion angle. Arthroscopy of the fetlock joint via the dorso-lateral portal allowed examination of the distal end of the large metacarpus and the proximal end of the first phalanx of the fourth digit. Arthroscopy via a dorso-medial approach allowed examination of the distal end of the large metacarpus and the proximal end of the first phalanx and the distal end of the third digit. The palmaro-lateral portal allowed examination of the sesamoid bones, the synovial membrane, and the synovial villi. The main complications recorded during arthroscopy were iatrogenic articular surface injury as well as obstruction of vision with the synovial villi. This is the first work to describe the normal arthroscopy of the fetlock joint in the dromedary camel, the arthroscopic portals, and the complications that could occur during and after arthroscopy. Further studies are required for diagnosis of pathological changes in the fetlock joint of the dromedary camel and for arthroscopy of other joints in the dromedary camel.

Measurement and Quantification of Gross Human Shoulder Motion

Directory of Open Access Journals (Sweden)

Jeremy T. Newkirk

2013-01-01

Full Text Available The shoulder girdle plays an important role in the large pointing workspace that humans enjoy. The goal of this work was to characterize the human shoulder girdle motion in relation to the arm. The overall motion of the human shoulder girdle was characterized based on motion studies completed on test subjects during voluntary (natural/unforced motion. The collected data from the experiments were used to develop surface fit equations that represent the position and orientation of the glenohumeral joint for a given humeral pointing direction. These equations completely quantify gross human shoulder girdle motion relative to the humerus. The equations are presented along with goodness-of-fit results that indicate the equations well approximate the motion of the human glenohumeral joint. This is the first time the motion has been quantified for the entire workspace, and the equations provide a reference against which to compare future work.

Indirect wrist MR arthrography: the effects of passive motion versus active exercise

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Schweitzer, M.E.; Natale, P.; Winalski, C.S.; Culp, R. [Thomas Jefferson University Hospital, Department of Radiology, Philadelphia, PA (United States)

2000-01-01

Purpose. In the wrist, to determine whether passive motion or active exercise yields a better indirect MR arthrographic effect following intravenous gadolinium administration.Design and patients. Twenty-six consecutive patients were studied by indirect wrist MR arthrography. In half active exercise and in half passive motion was performed. Four regions of interest were studied including the distal radioulnar joint, the radiocarpal joint, the midcarpal joint, and the triangular fibrocartilage. Ranges and means of signal intensity were calculated. Surgical follow-up was performed in 22 patients.Results. The joint fluid intensity was greatest in the distal radioulnar joint. Fluid signal intensity was greater and more consistent in the passive motion group although the results did not achieve statistical significance. Imaging accuracy appeared similar in the two groups and was excellent for the triangular fibrocartilage (100%) and scapholunate ligaments (96%).Conclusion. Active exercise and passive motion yield similar degrees of wrist arthrographic effect, but the effect of passive motion is somewhat more consistent. Preliminary data show good accuracy for internal derangements. (orig.)

The relation between geometry and function of the ankle joint complex: a biomechanical review.

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Kleipool, Roeland P; Blankevoort, Leendert

2010-05-01

This review deals with the relation between the anatomy and function of the ankle joint complex. The questions addressed are how high do the forces in the ankle joint get, where can the joints go (range of motion) and where do they go during walking and running. Finally the role of the ligaments and the articular surfaces is discussed, i.e. how does it happen. The magnitude of the loads on the ankle joint complex are primarily determined by muscle activity and can be as high as four times the body weight during walking. For the maximal range of motion, plantar and dorsiflexion occurs in the talocrural joint and marginally at the subtalar joint. In-eversion takes place at both levels. The functional range of motion is well within the limits of the maximal range of motion. The ligaments do not contribute to the forces for the functional range of motion but determine the maximal range of motion together with the articular surfaces. The geometry of the articular surfaces primarily determines the kinematics. Clinical studies must include these anatomical aspects to better understand the mechanism of injury, recovery, and interventions. Models can elucidate the mechanism by which the anatomy relates to the function. The relation between the anatomy and mechanical properties of the joint structures and joint function should be considered for diagnosis and treatment of ankle joint pathology.

Predicting articulated human motion from spatial processes

DEFF Research Database (Denmark)

Hauberg, Søren; Pedersen, Kim Steenstrup

2011-01-01

recent work where prior models are derived in terms of joint angles. This approach has several advantages. First of all, it allows us to construct motion models in low dimensional spaces, which makes motion estimation more robust. Secondly, as many types of motion are easily expressed in spatial...

Relationship Between the Range of Motion and Isometric Strength of Elbow and Shoulder Joints and Ball Velocity in Women Team Handball Players.

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Schwesig, René; Hermassi, Souhail; Wagner, Herbert; Fischer, David; Fieseler, Georg; Molitor, Thomas; Delank, Karl-Stefan

2016-12-01

Schwesig, R, Hermassi, S, Wagner, H, Fischer, D, Fieseler, G, Molitor, T, and Delank, K-S. Relationship between the range of motion and isometric strength of elbow and shoulder joints and ball velocity in women team handball players. J Strength Cond Res 30(12): 3428-3435, 2016-The aims of this study were to investigate relationships between isometric strength and range of motion (ROM) of shoulder and elbow joints and compare 2 different team handball throwing techniques in women team handball. Twenty highly experienced women team handball players (age: 20.7 ± 2.9 years; body mass: 68.4 ± 6.0 kg; and height: 1.74 ± 0.06 m) participated in this study. The isometric strength (hand-held dynamometer) and ROM (goniometer) of shoulder and elbow joints were measured at the beginning of the preseasonal training. After clinical examination, the subjects performed 3 standing throws with run-up (10 m) and 3 jump throws over a hurdle (0.20 m). The mean ball velocity was calculated from 3 attempts and measured using a radar gun. The results showed that the ball velocity of the standing throw with run-up (vST) was significantly higher than that of the jump throw (vJT) (25.5 ± 1.56 vs. 23.2 ± 1.31 m·s; p handball players.

The effect of postoperative passive motion on rotator cuff healing in a rat model.

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Peltz, Cathryn D; Dourte, Leann M; Kuntz, Andrew F; Sarver, Joseph J; Kim, Soung-Yon; Williams, Gerald R; Soslowsky, Louis J

2009-10-01

Surgical repairs of torn rotator cuff tendons frequently fail. Immobilization has been shown to improve tissue mechanical properties in an animal model of rotator cuff repair, and passive motion has been shown to improve joint mechanics in animal models of flexor tendon repair. Our objective was to determine if daily passive motion would improve joint mechanics in comparison with continuous immobilization in a rat rotator cuff repair model. We hypothesized that daily passive motion would result in improved passive shoulder joint mechanics in comparison with continuous immobilization initially and that there would be no differences in passive joint mechanics or insertion site mechanical properties after four weeks of remobilization. A supraspinatus injury was created and was surgically repaired in sixty-five Sprague-Dawley rats. Rats were separated into three postoperative groups (continuous immobilization, passive motion protocol 1, and passive motion protocol 2) for two weeks before all underwent a remobilization protocol for four weeks. Serial measurements of passive shoulder mechanics (internal and external range of motion and joint stiffness) were made before surgery and at two and six weeks after surgery. After the animals were killed, collagen organization and mechanical properties of the tendon-to-bone insertion site were determined. Total range of motion for both passive motion groups (49% and 45% of the pre-injury values) was less than that for the continuous immobilization group (59% of the pre-injury value) at two weeks and remained significantly less following four weeks of remobilization exercise. Joint stiffness at two weeks was increased for both passive motion groups in comparison with the continuous immobilization group. At both two and six weeks after repair, internal range of motion was significantly decreased whereas external range of motion was not. There were no differences between the groups in terms of collagen organization or mechanical

Relevance of adjacent joint imaging in the evaluation of ankle fractures.

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Antoci, Valentin; Patel, Shaun P; Weaver, Michael J; Kwon, John Y

2016-10-01

Routinely obtaining adjacent joint radiographs when evaluating patients with ankle fractures may be of limited clinical utility and an unnecessary burden, particularly in the absence of clinical suspicion for concomitant injuries. One thousand, three hundred and seventy patients who sustained ankle fractures over a 5-year period presenting to two level 1 trauma centers were identified. Medical records were retrospectively reviewed for demographics, physical examination findings, and radiographic information. Analyses included descriptive statistics along with sensitivity and predictive value calculations for the presence of adjacent joint fracture. Adjacent joint imaging (n=1045 radiographs) of either the knee or foot was obtained in 873 patients (63.7%). Of those, 75/761 patients (9.9%) demonstrated additional fractures proximal to the ankle joint, most commonly of the proximal fibula. Twenty-two of 284 (7.7%) demonstrated additional fractures distal to the ankle joint, most commonly of the metatarsals. Tenderness to palpation demonstrated sensitivities of 0.92 and 0.77 and positive predictive values of 0.94 and 0.89 for the presence of proximal and distal fractures, respectively. Additionally, 19/22 (86.4%) of patients sustaining foot fractures had their injury detectable on initial ankle X-rays. Overall, only 5.5% (75/1370) of patients sustained fractures proximal to the ankle and only 0.2% (3/1370) of patients had additional foot fractures not evident on initial ankle X-rays. The addition of adjacent joint imaging for the evaluation of patients sustaining ankle fractures is low yield. As such, patient history, physical examination, and clinical suspicion should direct the need for additional X-rays. Level IV. Copyright © 2016 Elsevier Ltd. All rights reserved.

Knee Motion Generation Method for Transfemoral Prosthesis Based on Kinematic Synergy and Inertial Motion.

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Sano, Hiroshi; Wada, Takahiro

2017-12-01

Previous research has shown that the effective use of inertial motion (i.e., less or no torque input at the knee joint) plays an important role in achieving a smooth gait of transfemoral prostheses in the swing phase. In our previous research, a method for generating a timed knee trajectory close to able-bodied individuals, which leads to sufficient clearance between the foot and the floor and the knee extension, was proposed using the inertial motion. Limb motions are known to correlate with each other during walking. This phenomenon is called kinematic synergy. In this paper, we measure gaits in level walking of able-bodied individuals with a wide range of walking velocities. We show that this kinematic synergy also exists between the motions of the intact limbs and those of the knee as determined by the inertial motion technique. We then propose a new method for generating the motion of the knee joint using its inertial motion close to the able-bodied individuals in mid-swing based on its kinematic synergy, such that the method can adapt to the changes in the motion velocity. The numerical simulation results show that the proposed method achieves prosthetic walking similar to that of able-bodied individuals with a wide range of constant walking velocities and termination of walking from steady-state walking. Further investigations have found that a kinematic synergy also exists at the start of walking. Overall, our method successfully achieves knee motion generation from the initiation of walking through steady-state walking with different velocities until termination of walking.

Wireless wearable range-of-motion sensor system for upper and lower extremity joints: a validation study.

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Kumar, Yogaprakash; Yen, Shih-Cheng; Tay, Arthur; Lee, Wangwei; Gao, Fan; Zhao, Ziyi; Li, Jingze; Hon, Benjamin; Tian-Ma Xu, Tim; Cheong, Angela; Koh, Karen; Ng, Yee-Sien; Chew, Effie; Koh, Gerald

2015-02-01

Range-of-motion (ROM) assessment is a critical assessment tool during the rehabilitation process. The conventional approach uses the goniometer which remains the most reliable instrument but it is usually time-consuming and subject to both intra- and inter-therapist measurement errors. An automated wireless wearable sensor system for the measurement of ROM has previously been developed by the current authors. Presented is the correlation and accuracy of the automated wireless wearable sensor system against a goniometer in measuring ROM in the major joints of upper (UEs) and lower extremities (LEs) in 19 healthy subjects and 20 newly disabled inpatients through intra (same) subject comparison of ROM assessments between the sensor system against goniometer measurements by physical therapists. In healthy subjects, ROM measurements using the new sensor system were highly correlated with goniometry, with 95% of differences sensor system were also highly correlated with goniometry, with 95% of the differences being < 20° and 25° for most movements in the major joints of UE and LE, respectively.

Compression of Human Motion Animation Using the Reduction of Interjoint Correlation

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Shiyu Li

2008-01-01

Full Text Available We propose two compression methods for the human motion in 3D space, based on the forward and inverse kinematics. In a motion chain, a movement of each joint is represented by a series of vector signals in 3D space. In general, specific types of joints such as end effectors often require higher precision than other general types of joints in, for example, CG animation and robot manipulation. The first method, which combines wavelet transform and forward kinematics, enables users to reconstruct the end effectors more precisely. Moreover, progressive decoding can be realized. The distortion of parent joint coming from quantization affects its child joint in turn and is accumulated to the end effector. To address this problem and to control the movement of the whole body, we propose a prediction method further based on the inverse kinematics. This method achieves efficient compression with a higher compression ratio and higher quality of the motion data. By comparing with some conventional methods, we demonstrate the advantage of ours with typical motions.

Compression of Human Motion Animation Using the Reduction of Interjoint Correlation

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Li Shiyu

2008-01-01

Full Text Available Abstract We propose two compression methods for the human motion in 3D space, based on the forward and inverse kinematics. In a motion chain, a movement of each joint is represented by a series of vector signals in 3D space. In general, specific types of joints such as end effectors often require higher precision than other general types of joints in, for example, CG animation and robot manipulation. The first method, which combines wavelet transform and forward kinematics, enables users to reconstruct the end effectors more precisely. Moreover, progressive decoding can be realized. The distortion of parent joint coming from quantization affects its child joint in turn and is accumulated to the end effector. To address this problem and to control the movement of the whole body, we propose a prediction method further based on the inverse kinematics. This method achieves efficient compression with a higher compression ratio and higher quality of the motion data. By comparing with some conventional methods, we demonstrate the advantage of ours with typical motions.

Orbit-attitude coupled motion around small bodies: Sun-synchronous orbits with Sun-tracking attitude motion

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Kikuchi, Shota; Howell, Kathleen C.; Tsuda, Yuichi; Kawaguchi, Jun'ichiro

2017-11-01

The motion of a spacecraft in proximity to a small body is significantly perturbed due to its irregular gravity field and solar radiation pressure. In such a strongly perturbed environment, the coupling effect of the orbital and attitude motions exerts a large influence that cannot be neglected. However, natural orbit-attitude coupled dynamics around small bodies that are stationary in both orbital and attitude motions have yet to be observed. The present study therefore investigates natural coupled motion that involves both a Sun-synchronous orbit and Sun-tracking attitude motion. This orbit-attitude coupled motion enables a spacecraft to maintain its orbital geometry and attitude state with respect to the Sun without requiring active control. Therefore, the proposed method can reduce the use of an orbit and attitude control system. This paper first presents analytical conditions to achieve Sun-synchronous orbits and Sun-tracking attitude motion. These analytical solutions are then numerically propagated based on non-linear coupled orbit-attitude equations of motion. Consequently, the possibility of implementing Sun-synchronous orbits with Sun-tracking attitude motion is demonstrated.

Isolated Proximal Tibiofibular Dislocation during Soccer

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Casey Chiu

2015-01-01

Full Text Available Proximal tibiofibular dislocations are rarely encountered in the Emergency Department (ED. We present a case involving a man presenting to the ED with left knee pain after making a sharp left turn on the soccer field. His physical exam was only remarkable for tenderness over the lateral fibular head. His X-rays showed subtle abnormalities of the tibiofibular joint. The dislocation was reduced and the patient was discharged from the ED with orthopedic follow-up.

Evaluating the Effects of local Injections of Bupivacaine and Triamcinolone Acetate on Shoulder Joint Pain and Restricted Range of Motion Following Cerebrovascular Accidents

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Asadollah Saadat Niaki M.D.

2011-06-01

Full Text Available Background: Shoulder pain is a common complication of cerebrovascular accidents. This study was conducted to assess the effects of local injections of bupivacaine and triamcinolone acetate on shoulder joint pain and on restricted range of motion following brain events. Methods: This single-blind clinical trial study included 35 patients with chronic shoulder pain (the controls and 35 patients with chronic shoulder pain due to brain events (the case group. The study was done at Imam Hossein Hospital & Gandhi Day Clinic during the year 2008-2010. The patients in the two groups received bupivacaine and triamcinolone acetate for subacromial bursa injection and suprascapular nerve block by following the protocol described by Dangoisse et al. The patients were followed up for 12 weeks and they were evaluated for pain and range of motion 1, 6, and 12 weeks after the injections.Results: The mean age of the patients was 60.9±9.07 years. Statistically significant improvements in pain score (P=0.001 and shoulder joint range of motion (P=0.001 were observed in patients with chronic shoulder pain versus patients with brain events 12 weeks after suprascapulare nerve block and subacromial bours injections by bupivacaine and triamcinolone acetate.Conclusion: Suprascapular nerve block and subacromial bursa injections of bupivacaine and triamcinolone acetate is a safe and efficacious treatment for the treatment of chronic shoulder pain and restricted range of motion but it is not efficacious or of significant value for the treatment of shoulder pain in patients with brain events.

Joint Center Estimation Using Single-Frame Optimization: Part 1: Numerical Simulation.

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Frick, Eric; Rahmatalla, Salam

2018-04-04

The biomechanical models used to refine and stabilize motion capture processes are almost invariably driven by joint center estimates, and any errors in joint center calculation carry over and can be compounded when calculating joint kinematics. Unfortunately, accurate determination of joint centers is a complex task, primarily due to measurements being contaminated by soft-tissue artifact (STA). This paper proposes a novel approach to joint center estimation implemented via sequential application of single-frame optimization (SFO). First, the method minimizes the variance of individual time frames’ joint center estimations via the developed variance minimization method to obtain accurate overall initial conditions. These initial conditions are used to stabilize an optimization-based linearization of human motion that determines a time-varying joint center estimation. In this manner, the complex and nonlinear behavior of human motion contaminated by STA can be captured as a continuous series of unique rigid-body realizations without requiring a complex analytical model to describe the behavior of STA. This article intends to offer proof of concept, and the presented method must be further developed before it can be reasonably applied to human motion. Numerical simulations were introduced to verify and substantiate the efficacy of the proposed methodology. When directly compared with a state-of-the-art inertial method, SFO reduced the error due to soft-tissue artifact in all cases by more than 45%. Instead of producing a single vector value to describe the joint center location during a motion capture trial as existing methods often do, the proposed method produced time-varying solutions that were highly correlated ( r > 0.82) with the true, time-varying joint center solution.

Joint Center Estimation Using Single-Frame Optimization: Part 1: Numerical Simulation

Directory of Open Access Journals (Sweden)

Eric Frick

2018-04-01

Full Text Available The biomechanical models used to refine and stabilize motion capture processes are almost invariably driven by joint center estimates, and any errors in joint center calculation carry over and can be compounded when calculating joint kinematics. Unfortunately, accurate determination of joint centers is a complex task, primarily due to measurements being contaminated by soft-tissue artifact (STA. This paper proposes a novel approach to joint center estimation implemented via sequential application of single-frame optimization (SFO. First, the method minimizes the variance of individual time frames’ joint center estimations via the developed variance minimization method to obtain accurate overall initial conditions. These initial conditions are used to stabilize an optimization-based linearization of human motion that determines a time-varying joint center estimation. In this manner, the complex and nonlinear behavior of human motion contaminated by STA can be captured as a continuous series of unique rigid-body realizations without requiring a complex analytical model to describe the behavior of STA. This article intends to offer proof of concept, and the presented method must be further developed before it can be reasonably applied to human motion. Numerical simulations were introduced to verify and substantiate the efficacy of the proposed methodology. When directly compared with a state-of-the-art inertial method, SFO reduced the error due to soft-tissue artifact in all cases by more than 45%. Instead of producing a single vector value to describe the joint center location during a motion capture trial as existing methods often do, the proposed method produced time-varying solutions that were highly correlated (r > 0.82 with the true, time-varying joint center solution.

Correlations among visual analogue scale, neck disability index, shoulder joint range of motion, and muscle strength in young women with forward head posture.

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Shin, Young Jun; Kim, Won Hyo; Kim, Seong Gil

2017-08-01

This study investigated the correlation between the neck disability index (NDI) and visual analogue scale (VAS), which are indicators of neck pain, shoulder joint range of motion (ROM), and muscle strength in women with a slight forward head posture. This study was carried out on 42 female college students attending Uiduk University in Gyeongju, Korea. The neck pain and disability index for each subject was measured using VAS and NDI, respectively. Two physiotherapists measured the shoulder joint ROM and muscle strengths of the subjects using a goniometer and a dynamometer, respectively. External rotation, internal rotation, and abduction of the shoulder joint were measured for each subject. A significant negative correlation between neck pain and shoulder joint ROM in external rotation and the muscle strength of the shoulder joint in abduction was found in the subjects. In addition, a significant positive correlation was observed between ROM in external rotation and muscle strength in abduction. This study showed a significant negative correlation between neck pain and ROM in external rotation as well as between neck pain and the muscle strength in abduction.

The Joint Adaptive Kalman Filter (JAKF) for Vehicle Motion State Estimation.

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Gao, Siwei; Liu, Yanheng; Wang, Jian; Deng, Weiwen; Oh, Heekuck

2016-07-16

This paper proposes a multi-sensory Joint Adaptive Kalman Filter (JAKF) through extending innovation-based adaptive estimation (IAE) to estimate the motion state of the moving vehicles ahead. JAKF views Lidar and Radar data as the source of the local filters, which aims to adaptively adjust the measurement noise variance-covariance (V-C) matrix 'R' and the system noise V-C matrix 'Q'. Then, the global filter uses R to calculate the information allocation factor 'β' for data fusion. Finally, the global filter completes optimal data fusion and feeds back to the local filters to improve the measurement accuracy of the local filters. Extensive simulation and experimental results show that the JAKF has better adaptive ability and fault tolerance. JAKF enables one to bridge the gap of the accuracy difference of various sensors to improve the integral filtering effectivity. If any sensor breaks down, the filtered results of JAKF still can maintain a stable convergence rate. Moreover, the JAKF outperforms the conventional Kalman filter (CKF) and the innovation-based adaptive Kalman filter (IAKF) with respect to the accuracy of displacement, velocity, and acceleration, respectively.

Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair.

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Lightsey, Harry M; Kantrowitz, David E; Swindell, Hasani W; Trofa, David P; Ahmad, Christopher S; Lynch, T Sean

2018-02-01

The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities. To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs. Cross-sectional study. Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced. Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises. Fifteen protocols (43%) required completion of

Effect of the walking speed to the lower limb joint angular displacements, joint moments and ground reaction forces during walking in water.

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Miyoshi, Tasuku; Shirota, Takashi; Yamamoto, Shin-ichiro; Nakazawa, Kimitaka; Akai, Masami

2004-06-17

The purpose of this study was to compare the changes in ground reaction forces (GRF), joint angular displacements (JAD), joint moments (JM) and electromyographic (EMG) activities that occur during walking at various speeds in water and on land. Fifteen healthy adults participated in this study. In the water experiments, the water depth was adjusted so that body weight was reduced by 80%. A video-motion analysis system and waterproof force platform was used to obtain kinematics and kinetics data and to calculate the JMs. Results revealed that (1) the anterior-posterior GRF patterns differed between walking in water and walking on land, whereas the medio-lateral GRF patterns were similar, (2) the JAD patterns of the hip and ankle were similar between water- and land-walking, whereas the range of motion at the knee joint was lower in water than on land, (3) the JMs in all three joints were lower in water than on land throughout the stance phase, and (4) the hip joint extension moment and hip extensor muscle EMG activity were increased as walking speed increase during walking in water. Rehabilitative water-walking exercise could be designed to incorporate large-muscle activities, especially of the lower-limb extensor muscles, through full joint range of motion and minimization of joint moments.

A joint-constraint model for human joints using signed distance-fields

DEFF Research Database (Denmark)

Engell-Nørregård, Morten Pol; Abel, Sarah Maria Niebe; Erleben, Kenny

2012-01-01

We present a local joint-constraint model for a single joint which is based on distance fields. Our model is fast, general, and well suited for modeling human joints. In this work, we take a geometric approach and model the geometry of the boundary of the feasible region, i.e., the boundary of all...... allowed poses. A region of feasible poses can be built by embedding motion captured data points in a signed distance field. The only assumption is that the feasible poses form a single connected set of angular values. We show how signed distance fields can be used to generate fast and general joint......-joint dependencies, or joints with more than three degrees of freedom. The resolution of the joint-constraints can be tweaked individually for each degree of freedom, which can be used to optimize memory usage. We perform a comparative study of the key-properties of various joint-constraint models, as well...

Identification of Nonlinear Micron-Level Mechanics for a Precision Deployable Joint

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Bullock, S. J.; Peterson, L. D.

1994-01-01

The experimental identification of micron-level nonlinear joint mechanics and dynamics for a pin-clevis joint used in a precision, adaptive, deployable space structure are investigated. The force-state mapping method is used to identify the behavior of the joint under a preload. The results of applying a single tension-compression cycle to the joint under a tensile preload are presented. The observed micron-level behavior is highly nonlinear and involves all six rigid body motion degrees-of-freedom of the joint. it is also suggests that at micron levels of motion modelling of the joint mechanics and dynamics must include the interactions between all internal components, such as the pin, bushings, and the joint node.

Some observations on lameness associated with pain in the proximal metacarpal region

International Nuclear Information System (INIS)

Dyson, S.

1988-01-01

The carpus and metacarpus of 40 horses which were free from lameness and 40 horses with lameness associated with the metacarpophalangeal joint or more distal limb were examined radiographically (Group A). The opacity of the proximal third of the third metacarpal bone was regular, with a uniform trabecular pattern. Osseous cyst-like lesions (OCLLs) were identified in the radial carpal bone (1), the ulnar carpal bone (2), the second carpal bone (15) and the fourth carpal bone (1). Thirty-one of 638 horses (4.8 percent) with forelimb lameness had pain localised to the proximal metacarpal region using local anaesthesia (Group B). All these horses were examined radiographically and an ultrasonographic examination was performed in seven. No definitive diagnosis was reached in 16 horses, seven of which had an OCLL in one of the carpal bones or the second metacarpal bone. One horse had, in addition to a poorly defined lucent area in the second carpal bone, radiographic evidence of degenerative joint disease of the carpometacarpal joint and an hypoechoic lesion in the accessory ligament of the deep digital flexor tendon. One horse had an hypoechoic lesion in the proximal part of the suspensory ligament. Abnormalities of the trabecular structure of the third metacarpal bone were identified in 13 horses. In 11 of these there was a vertically orientated lucent line, usually surrounded by sclerotic bone. These lucent lines may represent fatigue fractures seen end on. In one horse an horizontal lucent line was seen. One of these 13 horses also had a lesion in the proximal part of the suspensory ligament. Ten of the 13 (77 per cent) horses with presumed fractures of the third metacarpal bone recovered completely, whereas only eight of the 16 (50 per cent) horses in which no definitive diagnosis was reached returned to their former function

Digital ranges of motion: normal values in young adults.

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Mallon, W J; Brown, H R; Nunley, J A

1991-09-01

Analysis of the range of motion of fingers was done in young (eighteen to thirty-five year old) adult volunteers with no history of previous injury to their hands. The data show that there are slight differences between the individual digits. Notably, metacarpophalangeal flexion and total active motion increase linearly in proceeding from the index to the small finger. There were also minor differences in comparing sexes. Women have greater extension at the metacarpophalangeal joint in both active and passive motion and have a greater total active motion at all digits as a result. A significant tenodesis effect was found at the distal interphalangeal joint in normal subjects. No differences were found that could be attributable to handedness.

Minimally invasive surgical treatment for unstable fractures of the proximal phalanx: intramedullary screw

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Marcio Aurélio Aita

2016-02-01

Full Text Available ABSTRACT OBJECTIVE: To analyze the clinical-functional parameters and quality of life of patients undergoing minimally invasive surgical treatment for extra-articular fractures of the proximal phalanx, using an intramedullary screw (Acutrak(r. METHODS: Between January 2011 and September 2014, a prospective study was conducted on 41 patients (48 fingers with unstable extra-articular fractures of the proximal phalanx, who underwent minimally invasive surgical treatment using an intramedullary screw (Acutrak(r. These patients were evaluated 12 months after the surgery by means of the DASH quality-of-life questionnaire, VAS pain scale, measurement of range of motion (ROM, in degrees and radiographic assessment. RESULTS: All the patients achieved adequate reduction and consolidation of their fractures. There were statistically significant improvements in quality of life on the DASH scale, pain on the VAS scale and range of motion. CONCLUSION: The minimally invasive technique for treating unstable extra-articular fractures of the proximal phalanx using an intramedullary screw (Acutrak(r is effective and safe, and it presents satisfactory clinical-functional results.

Cervical spine motion: radiographic study

International Nuclear Information System (INIS)

Morgan, J.P.; Miyabayashi, T.; Choy, S.

1986-01-01

Knowledge of the acceptable range of motion of the cervical spine of the dog is used in the radiographic diagnosis of both developmental and degenerative diseases. A series of radiographs of mature Beagle dogs was used to identify motion within sagittal and transverse planes. Positioning of the dog's head and neck was standardized, using a restraining board, and mimicked those thought to be of value in diagnostic radiology. The range of motion was greatest between C2 and C5. Reports of severe disk degeneration in the cervical spine of the Beagle describe the most severely involved disks to be C4 through C7. Thus, a high range of motion between vertebral segments does not seem to be the cause for the severe degenerative disk disease. Dorsoventral slippage between vertebral segments was seen, but was not accurately measured. Wedging of disks was clearly identified. At the atlantoaxio-occipital region, there was a high degree of motion within the sagittal plane at the atlantoaxial and atlanto-occipital joints; the measurement can be a guideline in the radiographic diagnosis of instability due to developmental anomalies in this region. Lateral motion within the transverse plane was detected at the 2 joints; however, motion was minimal, and the measurements seemed to be less accurate because of rotation of the cervical spine. Height of the vertebral canal was consistently noted to be greater at the caudal orifice, giving some warning to the possibility of overdiagnosis in suspected instances of cervical spondylopathy

Roller-massager application to the quadriceps and knee-joint range of motion and neuromuscular efficiency during a lunge.

Science.gov (United States)

Bradbury-Squires, David J; Noftall, Jennifer C; Sullivan, Kathleen M; Behm, David G; Power, Kevin E; Button, Duane C

2015-02-01

Roller massagers are used as a recovery and rehabilitative tool to initiate muscle relaxation and improve range of motion (ROM) and muscular performance. However, research demonstrating such effects is lacking. To determine the effects of applying a roller massager for 20 and 60 seconds on knee-joint ROM and dynamic muscular performance. Randomized controlled clinical trial. University laboratory. Ten recreationally active men (age = 26.6 ± 5.2 years, height = 175.3 ± 4.3 cm, mass = 84.4 ± 8.8 kg). Participants performed 3 randomized experimental conditions separated by 24 to 48 hours. In condition 1 (5 repetitions of 20 seconds) and condition 2 (5 repetitions of 60 seconds), they applied a roller massager to the quadriceps muscles. Condition 3 served as a control condition in which participants sat quietly. Visual analog pain scale, electromyography (EMG) of the vastus lateralis (VL) and biceps femoris during roller massage and lunge, and knee-joint ROM. We found no differences in pain between the 20-second and 60-second roller-massager conditions. During 60 seconds of roller massage, pain was 13.5% (5.7 ± 0.70) and 20.6% (6.2 ± 0.70) greater at 40 seconds and 60 seconds, respectively, than at 20 seconds (P joint ROM was 10% and 16% greater in the 20-second and 60-second roller-massager conditions, respectively, than the control condition (P joint ROM and neuromuscular efficiency during a lunge.

An anatomical study of the proximal aspect of the medial femoral condyle to define the proximal-distal condylar length

Directory of Open Access Journals (Sweden)

Chia-Ming Chang

2017-01-01

Full Text Available Objective: Despite its possible role in knee arthroplasty, the proximal-distal condylar length (PDCL of the femur has never been reported in the literature. We conducted an anatomic study of the proximal aspect of the medial femoral condyle to propose a method for measuring the PDCL. Materials and Methods: Inspection of dried bone specimens was carried out to assure the most proximal condylar margin (MPCM as the eligible starting point to measure the PDCL. Simulation surgery was performed on seven pairs of cadaveric knees to verify the clinical application of measuring the PDCL after locating the MPCM. Interobserver reliability of this procedure was also analyzed. Results: Observation of the bone specimens showed that the MPCM is a concavity formed by the junction of the distal end of the supracondylar ridge and the proximal margin of the medial condyle. This anatomically distinctive structure made the MPCM an unambiguous landmark. The cadaveric simulation surgical dissection demonstrated that the MPCM is easily accessed in a surgical setting, making the measurement of the PDCL plausible. The intraclass correlation coefficient was 0.78, indicating good interobserver reliability for this technique. Conclusion: This study has suggested that the PDCL can be measured based on the MPCM in a surgical setting. PDCL measurement might be useful in joint line position management, selection of femoral component sizes, and other applications related to the proximal-distal dimension of the knee. Further investigation is required.

Intravoxel incoherent motion magnetic resonance imaging of the knee joint in children with juvenile idiopathic arthritis

Energy Technology Data Exchange (ETDEWEB)

Hilbert, Fabian; Sauer, Alexander; Koestler, Herbert [University Hospital Wuerzburg, Department of Diagnostic and Interventional Radiology, Wuerzburg (Germany); Holl-Wieden, Annette [University Hospital Wuerzburg, Department of Paediatrics, Wuerzburg (Germany); Neubauer, Henning [University Hospital Wuerzburg, Department of Diagnostic and Interventional Radiology, Wuerzburg (Germany); University Hospital Ulm, Department of Diagnostic and Interventional Radiology, Ulm (Germany)

2017-05-15

MRI of synovitis relies on use of a gadolinium-based contrast agent. Diffusion-weighted MRI (DWI) visualises thickened synovium but is of limited use in the presence of joint effusion. To investigate the feasibility and diagnostic accuracy of diffusion-weighted MRI with intravoxel incoherent motion (IVIM) for diagnosing synovitis in the knee joint of children with juvenile idiopathic arthritis. Twelve consecutive children with confirmed or suspected juvenile idiopathic arthritis (10 girls, median age 11 years) underwent MRI with contrast-enhanced T1-weighted imaging and DWI at 1.5 T. Read-out segmented multi-shot DWI was acquired at b values of 0 s/mm{sup 2}, 200 s/mm{sup 2}, 400 s/mm{sup 2} and 800 s/mm{sup 2}. We calculated the IVIM parameters perfusion fraction (f) and tissue diffusion coefficient (D). Diffusion-weighted images at b=800 s/mm{sup 2}, f parameter maps and post-contrast T1-weighted images were retrospectively assessed by two independent readers for synovitis using the Juvenile Arthritis MRI Scoring system. Seven (58%) children showed synovial hypertrophy on contrast-enhanced imaging. Diagnostic ratings for synovitis on DWI and on f maps were fully consistent with contrast-enhanced imaging, the diagnostic reference. Two children had equivocal low-confidence assessments on DWI. Median f was 6.7±2.0% for synovitis, 2.1±1.2% for effusion, 5.0±1.0% for muscle and 10.6±5.7% for popliteal lymph nodes. Diagnostic confidence was higher based on f maps in three (25%) children and lower in one child (8%), as compared to DWI. DWI with IVIM reliably visualises synovitis of the knee joint. Perfusion fraction maps differentiate thickened synovium from joint effusion and hence increase diagnostic confidence. (orig.)

Proximity sensing of electrostatic induction electret nanoparticles device using separation electrode

Directory of Open Access Journals (Sweden)

Jianxiong Zhu

2017-04-01

Full Text Available We reported a two dimensional self-powered proximity sensor based on nanoparticles polytetrafluoroethylene (PTFE electrostatic induction electret using separation electrode. The structural pattern was carefully designed for identifying the specific position on the horizontal plane. When the separation electrode is motioned above the sensor, the induced charges on electrodes will change based on the coupling effect of the electret film. Experiment results showed that the proximity sensor works well with the velocity 0.05 m/s. We also found that the prototype have a good stability even with a huge uncontrolled perturbation on the Y direction. Our work could be a significant step forward in self-powered proximity sensing technology, with a wide range of potential applications in touchpad, robotics, and safety-monitoring device.

Biomechanics of the natural, arthritic, and replaced human ankle joint

Science.gov (United States)

2014-01-01

The human ankle joint complex plays a fundamental role in gait and other activities of daily living. At the same time, it is a very complicated anatomical system but the large literature of experimental and modelling studies has not fully described the coupled joint motion, position and orientation of the joint axis of rotation, stress and strain in the ligaments and their role in guiding and stabilizing joint motion, conformity and congruence of the articular surfaces, patterns of contact at the articular surfaces, patterns of rolling and sliding at the joint surfaces, and muscle lever arm lengths. The present review article addresses these issues as described in the literature, reporting the most recent relevant findings. PMID:24499639

On the analysis of condylar path versus real motion of the temporomandibular joint: application for Sicat Function.

Science.gov (United States)

Kordaß, Bernd; Ruge, Sebastian

2015-01-01

Analysis of temporomandibular joint (TMJ) function using condylar path tracings is a challenge in functionally oriented dentistry. In most cases, reference points on the skin surface over the TMJ region are defined as "arbitrary", "individual" or "kinematic" condylar hinge axis points, which are displayed as "condylar paths" in motion. To what extent these reference points represent the actual condylar paths in each individual patient is ultimately unclear because the geometric relationship of the actual condyle to the selected reference point is usually unknown. Depending on the location of the point on the condyle and the centers of rotation of mandibular movement, these trajectories can vary greatly during combined rotational and sliding movements (eg, opening and closing movements of the mandible); this represents a grid of points located in the vicinity of the TMJ. To record the actual condylar path as the movement trajectory of a given point (eg, the condylar center), technological solutions are needed with which to link the tracing technology with the appropriate imaging technology capable of scanning the condyle, including the points of interest, and displaying them in real dynamic motion. Sicat Function (Sicat, D-Bonn) is such a solution. Sicat Function links cone beam computed tomography (CBCT) scans (made using the Galileos CBCT scanner; Sirona, Bensheim, Germany) with ultrasound-based, three-dimensional (3D) functional jaw movement recordings of the mandible (made using the JMT+ Jaw Motion Tracker; Sicat, Bonn, Germany). Digital images of the dental arches acquired with the intraoral scanner Cerec system (Sirona) can also be superimposed. This results in the generation of a 3D model of the bony mandible, including the TMJ, which reproduces the 3D real dynamic movement of the condyles simultaneously with that of the condylar paths at defined points (with the condylar centers being a particular point of interest). Sicat Function is an integrated, digital

Nutrition of the anterior cruciate ligament. Effects of continuous passive motion

International Nuclear Information System (INIS)

Skyhar, M.J.; Danzig, L.A.; Hargens, A.R.; Akeson, W.H.

1985-01-01

Twelve freshly killed mature male rabbits were used to study the effects of continuous passive motion (CPM) on regional and overall nonvascular nutritional pathways of the anterior cruciate ligament (ACL). One hundred fifty microcuries of 35 S-sulfate was injected intraarticularly into each knee joint. The right knee underwent CPM for 1 hour, while the left knee remained immobilized. Both knee joints were then isolated and immediately frozen. The ACLs were removed while still mostly frozen, and sectioned into anterior, middle, and posterior thirds for the six rabbits in Group 1, and proximal, middle, and distal thirds for the six rabbits in Group 2. In addition, quadriceps tendon samples were harvested from each limb of three rabbits. After appropriate processing, all samples were counted in a scintillation counter, and counts per minute per milligram of tissue were calculated. There was significantly higher uptake in rest extremity ACLs compared to CPM extremity ACLs (P = 0.0001). No significant difference was demonstrated in regional uptake comparing respective thirds of the ACL in either Group 1 or Group 2. Quadriceps tendon uptake trended higher in the limbs exposed to CPM compared to those maintained at rest (P = 0.14). The ACL uses diffusion as a primary nutrient pathway. CPM does not increase nutrient uptake by the ACL in this avascular model, but CPM may facilitate transport of metabolites out of the joint. No regional differences in uptake within the ACL occurred in either group

The Importance of Spatiotemporal Information in Biological Motion Perception: White Noise Presented with a Step-like Motion Activates the Biological Motion Area.

Science.gov (United States)

Callan, Akiko; Callan, Daniel; Ando, Hiroshi

2017-02-01

Humans can easily recognize the motion of living creatures using only a handful of point-lights that describe the motion of the main joints (biological motion perception). This special ability to perceive the motion of animate objects signifies the importance of the spatiotemporal information in perceiving biological motion. The posterior STS (pSTS) and posterior middle temporal gyrus (pMTG) region have been established by many functional neuroimaging studies as a locus for biological motion perception. Because listening to a walking human also activates the pSTS/pMTG region, the region has been proposed to be supramodal in nature. In this study, we investigated whether the spatiotemporal information from simple auditory stimuli is sufficient to activate this biological motion area. We compared spatially moving white noise, having a running-like tempo that was consistent with biological motion, with stationary white noise. The moving-minus-stationary contrast showed significant differences in activation of the pSTS/pMTG region. Our results suggest that the spatiotemporal information of the auditory stimuli is sufficient to activate the biological motion area.

Sacroiliac joint stability: Finite element analysis of implant number, orientation, and superior implant length.

Science.gov (United States)

Lindsey, Derek P; Kiapour, Ali; Yerby, Scott A; Goel, Vijay K

2018-03-18

To analyze how various implants placement variables affect sacroiliac (SI) joint range of motion. An experimentally validated finite element model of the lumbar spine and pelvis was used to simulate a fusion of the SI joint using various placement configurations of triangular implants (iFuse Implant System ® ). Placement configurations were varied by changing implant orientation, superior implant length, and number of implants. The range of motion of the SI joint was calculated using a constant moment of 10 N-m with a follower load of 400 N. The changes in motion were compared between the treatment groups to assess how the different variables affected the overall motion of the SI joint. Transarticular placement of 3 implants with superior implants that end in the middle of the sacrum resulted in the greatest reduction in range of motion (flexion/extension = 73%, lateral bending = 42%, axial rotation = 72%). The range of motions of the SI joints were reduced with use of transarticular orientation (9%-18%) when compared with an inline orientation. The use of a superior implant that ended mid-sacrum resulted in median reductions of (8%-14%) when compared with a superior implant that ended in the middle of the ala. Reducing the number of implants, resulted in increased SI joint range of motions for the 1 and 2 implant models of 29%-133% and 2%-39%, respectively, when compared with the 3 implant model. Using a validated finite element model we demonstrated that placement of 3 implants across the SI joint using a transarticular orientation with superior implant reaching the sacral midline resulted in the most stable construct. Additional clinical studies may be required to confirm these results.

Pathological Knee Joint Motion Analysis By High Speed Cinephotography

Science.gov (United States)

Baumann, Jurg U.

1985-02-01

The use of cinephotography for evaluation of disturbed knee joint function was compared in three groups of patients. While a sampling rate of 50 images per second was adequate for patients with neuromuscular disorders, a higher frequency of around 300 i.p.s. is necessary in osteoarthritis and ligamentous knee joint injuries, but the task of digitizing is prohibitive unless automated.

Kinematic evaluation of movement smoothness in golf: relationship between the normalized jerk cost of body joints and the clubhead.

Science.gov (United States)

Choi, Ahnryul; Joo, Su-Bin; Oh, Euichaul; Mun, Joung Hwan

2014-02-26

When the human body is introduced to a new motion or movement, it learns the placement of different body parts, sequential muscle control, and coordination between muscles to achieve necessary positions, and it hones this new skill over time and repetition. Previous studies have demonstrated definite differences in the smoothness of body movements with different levels of training, i.e., amateurs compared with professionals. Therefore, we tested the hypothesis that skilled golfers swing a driver with a smoother motion than do unskilled golfers. In addition, the relationship between the smoothness of body joints and that of the clubhead was evaluated to provide further insight into the mechanism of smooth golf swing. Two subject groups (skilled and unskilled) participated in the experiment. The skilled group comprised 20 male professional golfers registered with the Korea Professional Golf Association, and the unskilled group comprised 19 amateur golfers who enjoy golf as a hobby. Six infrared cameras (VICON460 system) were used to record the 3D trajectories of markers attached to the clubhead and body segments, and the resulting data was evaluated with kinematic analysis. A physical quantity called jerk was calculated to investigate differences in smoothness during downswing between the two study groups. The hypothesis that skilled golfers swing a driver with a smoother motion than do unskilled golfers was supported. The normalized jerk of the clubhead of skilled golfers was lower than that of unskilled golfers in the anterior/posterior, medial/lateral, and proximal/distal directions. Most human joints, especially in the lower body, had statistically significant lower normalized jerk values in the skilled group. In addition, the normalized jerk of the skilled group's lower body joints had a distinct positive correlation with the normalized jerk of the clubhead with r = 0.657 (p golf swings and, eventually, to improve golf performance.

Continuous Wavelet Transform Analysis of Surface Electromyography for Muscle Fatigue Assessment on the Elbow Joint Motion

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Triwiyanto Triwiyanto

2017-01-01

Full Text Available Studying muscle fatigue plays an important role in preventing the risks associated with musculoskeletal disorders. The effect of elbow-joint angle on time-frequency parameters during a repetitive motion provides valuable information in finding the most accurate position of the angle causing muscle fatigue. Therefore, the purpose of this study is to analyze the effect of muscle fatigue on the spectral and time-frequency domain parameters derived from electromyography (EMG signals using the Continuous Wavelet Transform (CWT. Four male participants were recruited to perform a repetitive motion (flexion and extension movements from a non-fatigue to fatigue condition. EMG signals were recorded from the biceps muscle. The recorded EMG signals were then analyzed offline using the complex Morlet wavelet. The time-frequency domain data were analyzed using the time-averaged wavelet spectrum (TAWS and the Scale-Average Wavelet Power (SAWP parameters. The spectral domain data were analyzed using the Instantaneous Mean Frequency (IMNF and the Instantaneous Mean Power Spectrum (IMNP parameters. The index of muscle fatigue was observed by calculating the increase of the IMNP and the decrease of the IMNF parameters. After performing a repetitive motion from non-fatigue to fatigue condition, the average of the IMNF value decreased by 15.69% and the average of the IMNP values increased by 84%, respectively. This study suggests that the reliable frequency band to detect muscle fatigue is 31.10-36.19Hz with linear regression parameters of 0.979mV^2Hz^(-1 and 0.0095mV^2Hz^(-1 for R^2 and slope, respectively.

Inertial Sensor-Based Motion Analysis of Lower Limbs for Rehabilitation Treatments

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Tongyang Sun

2017-01-01

Full Text Available The hemiplegic rehabilitation state diagnosing performed by therapists can be biased due to their subjective experience, which may deteriorate the rehabilitation effect. In order to improve this situation, a quantitative evaluation is proposed. Though many motion analysis systems are available, they are too complicated for practical application by therapists. In this paper, a method for detecting the motion of human lower limbs including all degrees of freedom (DOFs via the inertial sensors is proposed, which permits analyzing the patient’s motion ability. This method is applicable to arbitrary walking directions and tracks of persons under study, and its results are unbiased, as compared to therapist qualitative estimations. Using the simplified mathematical model of a human body, the rotation angles for each lower limb joint are calculated from the input signals acquired by the inertial sensors. Finally, the rotation angle versus joint displacement curves are constructed, and the estimated values of joint motion angle and motion ability are obtained. The experimental verification of the proposed motion detection and analysis method was performed, which proved that it can efficiently detect the differences between motion behaviors of disabled and healthy persons and provide a reliable quantitative evaluation of the rehabilitation state.

Variability of United States Online Rehabilitation Protocols for Proximal Hamstring Tendon Repair

Science.gov (United States)

Lightsey, Harry M.; Kantrowitz, David E.; Swindell, Hasani W.; Trofa, David P.; Ahmad, Christopher S.; Lynch, T. Sean

2018-01-01

Background: The optimal postoperative rehabilitation protocol following repair of complete proximal hamstring tendon ruptures is the subject of ongoing investigation, with a need for more standardized regimens and evidence-based modalities. Purpose: To assess the variability across proximal hamstring tendon repair rehabilitation protocols published online by United States (US) orthopaedic teaching programs. Study Design: Cross-sectional study. Methods: Online proximal hamstring physical therapy protocols from US academic orthopaedic programs were reviewed. A web-based search using the search term complete proximal hamstring repair rehabilitation protocol provided an additional 14 protocols. A comprehensive scoring rubric was developed after review of all protocols and was used to assess each protocol for both the presence of various rehabilitation components and the point at which those components were introduced. Results: Of 50 rehabilitation protocols identified, 35 satisfied inclusion criteria and were analyzed. Twenty-five protocols (71%) recommended immediate postoperative bracing: 12 (34%) prescribed knee bracing, 8 (23%) prescribed hip bracing, and 5 (14%) did not specify the type of brace recommended. Fourteen protocols (40%) advised immediate nonweightbearing with crutches, while 16 protocols (46%) permitted immediate toe-touch weightbearing. Advancement to full weightbearing was allowed at a mean of 7.1 weeks (range, 4-12 weeks). Most protocols (80%) recommended gentle knee and hip passive range of motion and active range of motion, starting at a mean 1.4 weeks (range, 0-3 weeks) and 4.0 weeks (range, 0-6 weeks), respectively. However, only 6 protocols (17%) provided specific time points to initiate full hip and knee range of motion: a mean 8.0 weeks (range, 4-12 weeks) and 7.8 weeks (range, 0-12 weeks), respectively. Considerable variability was noted in the inclusion and timing of strengthening, stretching, proprioception, and cardiovascular exercises

[Compensatory joints at the pelvis (author's transl)].

Science.gov (United States)

Schumacher, G; Weber, M

1980-10-01

An osteochondrosis ischio-pubica represents a "testing site" for the integrity of the pelvis not only during child age but in adults as well. If all naturally available compensatory mechanisms have been exhausted especially following a change of range of motion in the pelvis ring structure, fatigue fractures or zones in transformation in the area typical of osteochondrosis ischio-pubica may appear. These fractures or transformation zones respectively to our mind have joint character, because they are capable of temporarily replacing lost mobility of physiological joints. Healing is achieved through rest, muscular balance and a specific physiotherapy. The purpose of this muscular training is to cushion all unphysiological motions in the pelvis and to support and boost the function of those joints still well preserved.

Interventions for treating proximal humeral fractures in adults

DEFF Research Database (Denmark)

Handoll, Helen H G; Brorson, Stig

2015-01-01

supervised exercise in a swimming pool plus home exercise.Eight trials, involving 567 older participants, evaluated surgical intervention for displaced fractures. There was high quality evidence of no clinically important difference in patient-reported shoulder and upper-limb function at one- or two......BACKGROUND: Fracture of the proximal humerus, often termed shoulder fracture, is a common injury in older people. The management of these fractures varies widely. This is an update of a Cochrane Review first published in 2001 and last updated in 2012. OBJECTIVES: To assess the effects (benefits...... and harms) of treatment and rehabilitation interventions for proximal humeral fractures in adults. SEARCH METHODS: We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and other databases, conference...

Quantitative analysis by MRI on condylar motion of the temporomandibular joint in patients applied with occlusal splints

International Nuclear Information System (INIS)

Saito, Hiroki

1999-01-01

The purpose of this study was to assess the feasibility of a newly developed quantitative motion analysis method for the mandibular condyle before and after application of occlusal splints. The subjects were 50 consecutive patients with internal derangement. Stabilization type splints were applied in 23 cases (46%), anterior repositioning type in 18 cases (36%) and pivot type in 9 cases (18%). All patients underwent MR imaging with a 1.5-T MR unit with a 3-inch dual surface coil. Pseudodynamic MR study of the opening cycle was obtained using multiplanar GRASS sequence (MPGR). Incremental and decremental sagittal MR images before and after splint application were transferred to the workstation. Software originally developed by Nakasato and Katsuragawa was used to analyze the condylar motion and path. After splint application, normalized position of displaced discs was seen in 11 cases (22%), and occurred most frequently with anterior repositioning type splints. In patients with anterior repositioning type splints, improvement in the condylar motion was most significant, In patients with normalized disc position after application of occlusal splints, abnormal figure-eight-shaped'' condylar paths were corrected in 9 of 10 cases. In the case with normalized disc position after application of anterior repositioning splint, the maximum rotational angle before application of the splint is larger than that of the case without normalized disc position. Rotational function of the condyle in the inferior joint space may be associated with disc recapturing. (K.H.)

T1ρ and T2 mapping of the proximal tibiofibular joint in relation to aging and cartilage degeneration

International Nuclear Information System (INIS)

Hirose, Jun; Nishioka, Hiroaki; Nakamura, Eiichi; Oniki, Yasunari; Yamashita, Yasuyuki; Mizuta, Hiroshi

2012-01-01

Objective: To study the effects of aging and cartilage degeneration of the proximal tibiofibular- and femorotibial joint (PTFJ, FTJ) on the cartilage of the PTFJ using T 1 ρ and T 2 mapping. Materials and methods: We performed sagittal T 1 ρ and T 2 mapping of the PTFJ and FTJ on 55 subjects with knee disorders. We placed 3 regions of interest (ROIs) on images of the cartilage in the PTFJ, medial femoral condyle (MFC), and medial tibia plateau (MTP). Correlation analysis was performed for the T 1 ρ and T 2 values of each ROI and the patient age and the osteoarthritic grade of the PTFJ and FTJ. Results: The T 1 ρ and T 2 values of the PTFJ were affected neither by aging nor the osteoarthritic grade of the FTJ. Values of the FTJ normalized to PTFJ values were correlated with the osteoarthritic grade of the FTJ in the MFC (r = 0.851 and 0.779, respectively) and the MTP (r = 0.635 and 0.762, respectively). There was a significant difference in the T 1 ρ but not the T 2 value of the PTFJ and MFC between normal and mildly osteoarthritic cartilage of each joint. Conclusion: We document that the T 1 ρ and T 2 values of PTFJ cartilage were not affected by aging or cartilage degeneration in the FTJ. The T 1 ρ value of the PTFJ may represent a useful internal standard reference for evaluating early degeneration of the FTJ

Exoskeleton Motion Control for Children Walking Rehabilitation

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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.

Sex Differences in Proximal Control of the Knee Joint

OpenAIRE

Mendiguchia, Jurdan; Ford, Kevin R.; Quatman, Carmen E.; Alentorn-Geli, Eduard; Hewett, Timothy E.

2011-01-01

Following the onset of maturation, female athletes have a significantly higher risk for anterior cruciate ligament (ACL) injury compared with male athletes. While multiple sex differences in lower-extremity neuromuscular control and biomechanics have been identified as potential risk factors for ACL injury in females, the majority of these studies have focused specifically on the knee joint. However, increasing evidence in the literature indicates that lumbopelvic (core) control may have a la...

'Magnetic Resonance Motion Imaging' for functional diagnosis of the musculo-skeletal system

International Nuclear Information System (INIS)

Friedrich, K.M.

2002-06-01

Purpose: radiological studies of joint and spine function are an important part of the diagnosis and therapy management for musculo-skeletal diseases affecting range-of-motion. The objective of this study was to investigate the integration and developement of the clinical application of currently available MR-tomographic techniques, which can be summarized as 'Magnetic Resonance Motion Imaging (MRMI)'. Material and methods: five healthy volunteers (three women and two men; mean age 21.8?4.4) and ten patients (eight women and two men; mean age 31.4?12.6) took part in the study. A total of 21 examinations with real-time motion-MRI were performed on selected peripheric joints (seven patellofemoral joints, six femorotibial joints, one cervical spine, two wrists, three ankles and two temporomandibular joints) with a 1.0T unit (Philips Intera T10) using T1-weighted gradient-echo and opposed-phase imaging sequences. For the examination of the patellofemoral joint, the femorotibial joint, the wrist and the tmj a dedicated positioning-device was used. Results were correlated with static MR-Images. Results: the quickly parcticable sequence of the examinations was not straining for the patients. The quality of imaging was only insignificantly lower as compared with static gradient-echo sequences. No artifacts were seen which could influence the evaluation. The visualisation of motions was very good. The quantification of the maximum extent of dysfunctions could be judged better with a higher sensitivity in real-time-mode than in static images. Conclusion: from the results of this study a three-step-plan for the radiodiagnostic procedure in cases of functional disorders of selected joints and the spine can be deduced, which uses static MR-imaging as first step. In case of unsolved questions MRMI is done (step 2). To obtain measurements, static MR-Images at different points of the motion range(kinematic MR-Imaging) should be done (step 3). This plan of 'motion-MRI' is well

Local Dynamic Stability Assessment of Motion Impaired Elderly Using Electronic Textile Pants.

Science.gov (United States)

Liu, Jian; Lockhart, Thurmon E; Jones, Mark; Martin, Tom

2008-10-01

A clear association has been demonstrated between gait stability and falls in the elderly. Integration of wearable computing and human dynamic stability measures into home automation systems may help differentiate fall-prone individuals in a residential environment. The objective of the current study was to evaluate the capability of a pair of electronic textile (e-textile) pants system to assess local dynamic stability and to differentiate motion-impaired elderly from their healthy counterparts. A pair of e-textile pants comprised of numerous e-TAGs at locations corresponding to lower extremity joints was developed to collect acceleration, angular velocity and piezoelectric data. Four motion-impaired elderly together with nine healthy individuals (both young and old) participated in treadmill walking with a motion capture system simultaneously collecting kinematic data. Local dynamic stability, characterized by maximum Lyapunov exponent, was computed based on vertical acceleration and angular velocity at lower extremity joints for the measurements from both e-textile and motion capture systems. Results indicated that the motion-impaired elderly had significantly higher maximum Lyapunov exponents (computed from vertical acceleration data) than healthy individuals at the right ankle and hip joints. In addition, maximum Lyapunov exponents assessed by the motion capture system were found to be significantly higher than those assessed by the e-textile system. Despite the difference between these measurement techniques, attaching accelerometers at the ankle and hip joints was shown to be an effective sensor configuration. It was concluded that the e-textile pants system, via dynamic stability assessment, has the potential to identify motion-impaired elderly.

Running in ostriches (Struthio camelus): three-dimensional joint axes alignment and joint kinematics.

Science.gov (United States)

Rubenson, Jonas; Lloyd, David G; Besier, Thor F; Heliams, Denham B; Fournier, Paul A

2007-07-01

Although locomotor kinematics in walking and running birds have been examined in studies exploring many biological aspects of bipedalism, these studies have been largely limited to two-dimensional analyses. Incorporating a five-segment, 17 degree-of-freedom (d.f.) kinematic model of the ostrich hind limb developed from anatomical specimens, we quantified the three-dimensional (3-D) joint axis alignment and joint kinematics during running (at approximately 3.3 m s(-1)) in the largest avian biped, the ostrich. Our analysis revealed that the majority of the segment motion during running in the ostrich occurs in flexion/extension. Importantly, however, the alignment of the average flexion/extension helical axes of the knee and ankle are rotated externally to the direction of travel (37 degrees and 21 degrees , respectively) so that pure flexion and extension at the knee will act to adduct and adbuct the tibiotarsus relative to the plane of movement, and pure flexion and extension at the ankle will act to abduct and adduct the tarsometatarsus relative to the plane of movement. This feature of the limb anatomy appears to provide the major lateral (non-sagittal) displacement of the lower limb necessary for steering the swinging limb clear of the stance limb and replaces what would otherwise require greater adduction/abduction and/or internal/external rotation, allowing for less complex joints, musculoskeletal geometry and neuromuscular control. Significant rotation about the joints' non-flexion/extension axes nevertheless occurs over the running stride. In particular, hip abduction and knee internal/external and varus/valgus motion may further facilitate limb clearance during the swing phase, and substantial non-flexion/extension movement at the knee is also observed during stance. Measurement of 3-D segment and joint motion in birds will be aided by the use of functionally determined axes of rotation rather than assumed axes, proving important when interpreting the

Correlation between generalized joint hypermobility and hallux valgus

Directory of Open Access Journals (Sweden)

A. A. Kardanov

2015-01-01

Full Text Available Purpose: to evaluate correlation between generalized joint hypermobility, forefoot deformities and elasticity of the first ray of the foot. Material and methods. We examined 138 patients with complaints related with deformities at the forefoot level. During this study the medical history was obtained, the elasticity type of the feet was defined and the degree of motion of the medial metatarsal-cuneiform joint was evaluated. Forefoot elasticity was identified by bringing together the heads I and V metatarsal bones with fingers. If convergence occurred with little resistance, those feet were called hyperelastic. The convergence of the heads I and V metatarsal bones of the foot with an average type of elasticity occurred with resistance. It was impossible to converge the heads of I and V metatarsal bones. Due to the results of weight-bearing and non-weight bearing X-ray, analysis of the main radiographic angles of the foot was performed: between I and V metatarsal bones, between the first and second metatarsal bones and between the first metatarsal bone and proximal phalanx of the great toe. Calculation formula of the forefoot flatness index, showing the average ratios of basic radiographic angles of the foot on the x-ray images (weight-bearing and non-weight bearing was created. An assessment of total joint hypermobility using Beighton scale and evaluation of first ray deformity using DuPont scale were performed. Statistical analysis of obtained data was performed, as a result of which significantly strong correlation between total joint hypermobility, forefoot elasticity and valgus deviation of the great toe were revealed. Results. 11% of the feet were hyperelastic. Calculation of the index of forefoot flatness showed that forefoot flatness wasn’t significant for a rigid foot - 5.6 %, for the feet with an average degree of mobility it was 6.0% and it was expressed for hypemobile feet - 12.3 %. Strong correlation relation between the forefeet

Effect of linear polarized near-infrared light irradiation on flexibility of shoulder and ankle joints.

Science.gov (United States)

Demura, S; Yamaji, S; Ikemoto, Y

2002-12-01

There is a possibility that heat stimulus by linear polarized near-infrared light irradiation (PL: Super Lizer HA-30, Tokyo Medical Laboratory) improves the range of joint motion, because the flexibility of soft-part tissues, such as a muscle or a tendon, is improved by increasing the muscle temperature. The purpose of this study was to examine the influence of PL-irradiation on the ranges of shoulder and ankle motions. 30 healthy young adults (15 males: mean+/-SD, age 19.1+/-0.8 yrs, height 173.3+/-4.6 cm, body mass 68.5+/-8.0 kg and 15 females: mean+/-SD, age 19.2+/-0.7 yrs, height 162.3+/-4.5 cm, body mass 58.1+/-6.6 kg) participated in the experiment under PL-irradiation and no-irradiation (placebo) conditions. the angles of shoulder and ankle joint motions were measured twice, before and after the PL- and placebo-irradiations. The angle of a motion was defined as the angle connecting 3 points at linearity as follows: for the shoulder, the greater trochanter, acromion, and caput ulnare, and for the ankle, the knee joint, fassa of lateral malleolus and metacarpal bone. Each angle was measured when a subject extended or flexed maximally without support. The trial-to-trial reliability of each range of joint motion was very high. All parameters in PL-irradiation were significantly larger in postirradiation than pre-irradiation, and the value of postirradiation in PL-irradiation was significantly greater than that for placebo. The ranges of shoulder and ankle motions in placebo-irradiation were also significantly greater in postirradiation than pre-irradiation. Moreover, the change rate for each range of joint motion between pre- and postirradiations was significantly greater in PL-irradiation in both joints. In PL-irradiation, most subject's motions were greater in postirradiation than pre-irradiation, but not in the placebo-irradiation. The effect of PL-irradiation tended to be greater on subjects with a small range of a joint motion. It is considered from the

Benign joint hypermobility syndrome

Directory of Open Access Journals (Sweden)

Iwona Słowińska

2014-11-01

Full Text Available Benign joint hypermobility syndrome (BJHS, commonly known as loose ligament syndrome, is a non-inflammatory rheumatic condition. It is characterised by a greater than normal range of motion of the joints of the limbs and spine. The prevalence of the syndrome in preschool-age children is estimated to be between 2% and 30%, depending on ethnic background (with higher prevalence in Asian and African populations, occurring most often in families with a history of the condition and more frequently in girls. This paper presents a case report of a 12-year-old girl. A broad differential diagnostic approach to recurrent joint inflammation with joint effusion and pain made it possible to establish a diagnosis of benign joint hypermobility syndrome. The child met the Brighton criteria; her Beighton score was 7 out of 9. Patient education aimed at eliminating abnormal joint movement and an appropriate rehabilitation programme play key roles in the treatment of BJHS.

Retrospective analysis of factors associated with outcome of proximal interphalangeal joint arthrodesis in 82 horses including Warmblood and Thoroughbred sport horses and Quarter Horses (1992-2014).

Science.gov (United States)

Herthel, T D; Rick, M C; Judy, C E; Cohen, N D; Herthel, D J

2016-09-01

Outcomes associated with arthrodesis of the proximal interphalangeal (PIP) joint in Quarter Horses used for Western performance activities are well documented but little is known regarding outcomes for other types of horses. To identify factors associated with outcomes, including breed and activity, after arthrodesis of the PIP joint in Warmbloods, Thoroughbreds and Quarter Horses. Retrospective case series. Surgical case records of 82 Quarter Horses principally engaged in Western performance and Thoroughbred or Warmblood breeds principally engaged in showing, showjumping and dressage, with arthrodesis of the PIP joint were reviewed. Arthrodesis was performed with either 3 transarticular cortex bone screws placed in lag fashion, a dynamic compression plate (DCP) with 2 transarticular cortex bone screws placed in lag fashion, or a locking compression plate (LCP) with 2 transarticular cortex bone screws placed in lag fashion. Demographic data, clinical presentation, radiographic findings, surgical technique, post operative treatment and complications were recorded. Long-term follow-up was obtained for all 82 horses. Osteoarthritis of the PIP joint was the most common presenting condition requiring arthrodesis, which was performed with either the 3 screw technique (n = 41), DCP fixation (n = 22), or LCP fixation (n = 19). Post operatively, 23/31 (74%) Warmbloods/Thoroughbreds and 44/51 (87%) Quarter Horses achieved successful outcomes. Thirteen of 23 (57%) Warmbloods/Thoroughbreds and 24 of 38 (63%) Quarter Horses, used for athletic performance, returned to successful competition. Within this subgroup of horses engaged in high-level activity, regardless of breed type, horses undergoing hindlimb arthrodesis were significantly more likely to return to successful competition (73%; 33/45) than those with forelimb arthrodesis (25%; 4/16, P = 0.002). Arthrodesis of the PIP joint in Warmbloods/Thoroughbreds and Quarter Horses results in a favourable outcome for return to

The shape of the hominoid proximal femur: a geometric morphometric analysis

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Harmon, Elizabeth H

2007-01-01

As part of the hip joint, the proximal femur is an integral locomotor component. Although a link between locomotion and the morphology of some aspects of the proximal femur has been identified, inclusive shapes of this element have not been compared among behaviourally heterogeneous hominoids. Previous analyses have partitioned complex proximal femoral morphology into discrete features (e.g. head, neck, greater trochanter) to facilitate conventional linear measurements. In this study, three-dimensional geometric morphometrics are used to examine the shape of the proximal femur in hominoids to determine whether femoral shape co-varies with locomotor category. Fourteen landmarks are recorded on adult femora of Homo, Pan, Gorilla, Pongo and Hylobates. Generalized Procrustes analysis (GPA) is used to adjust for position, orientation and scale among landmark configurations. Principal components analysis is used to collapse and compare variation in residuals from GPA, and thin-plate spline analysis is used to visualize shape change among taxa. The results indicate that knucklewalking African apes are similar to one another in femoral shape, whereas the more suspensory Asian apes diverge from the African ape pattern. The shape of the human and orangutan proximal femur converge, a result that is best explained in terms of the distinct requirements for locomotion in each group. These findings suggest that the shape of the proximal femur is brought about primarily by locomotor behaviour. PMID:17310545

Coupled motions in human and porcine thoracic and lumbar spines

NARCIS (Netherlands)

Kingma, Idsart; Busscher, Iris; van der Veen, Albert J.; Verkerke, Gijsbertus J.; Veldhuizen, Albert G.; Homminga, Jasper; van Dieën, Jaap H.

2018-01-01

Coupled motions, i.e., motions along axes other than the loaded axis, have been reported to occur in the human spine, and are likely to be influenced by inclined local axes due to the sagittal plane spine curvature. Furthermore, the role of facet joints in such motions is as yet unclear. Therefore,

Coupled motions in human and porcine thoracic and lumbar spines

NARCIS (Netherlands)

Kingma, Idsart; Busscher, Iris; van der Veen, Albert J.; Verkerke, Gijsbertus J.; Veldhuizen, Albert G.; Homminga, Jasper; van Dieën, Jaap H.

2017-01-01

Coupled motions, i.e., motions along axes other than the loaded axis, have been reported to occur in the human spine, and are likely to be influenced by inclined local axes due to the sagittal plane spine curvature. Furthermore, the role of facet joints in such motions is as yet unclear. Therefore,

Are the Kinematics of the Knee Joint Altered during the Loading Response Phase of Gait in Individuals with Concurrent Knee Osteoarthritis and Complaints of Joint Instability? A Dynamic Stereo X-ray Study

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Farrokhi, Shawn; Tashman, Scott; Gil, Alexandra B.; Klatt, Brian A.; Fitzgerald, G. Kelley

2011-01-01

Background Joint instability has been suggested as a risk factor for knee osteoarthritis and a cause of significant functional declines in those with symptomatic disease. However, the relationship between altered knee joint mechanics and self-reports of instability in individuals with knee osteoarthritis remains unclear. Methods Fourteen subjects with knee osteoarthritis and complaints of joint instability and 12 control volunteers with no history of knee disease were recruited for this study. Dynamic stereo X-ray technology was used to assess the three-dimensional kinematics of the knee joint during the loading response phase of gait. Findings Individuals with concurrent knee osteoarthritis and joint instability demonstrated significantly reduced flexion and internal/external rotation knee motion excursions during the loading response phase of gait (P knee joint at initial contact was significantly different (P knee osteoarthritis and joint instability. However, the anteroposterior and mediolateral tibiofemoral joint positions at initial contact and the corresponding total joint translations were similar between groups during the loading phase of gait. Interpretations The rotational patterns of tibiofemoral joint motion and joint alignments reported for individuals with concurrent knee osteoarthritis and joint instability are consistent with those previously established for individuals with knee osteoarthritis. Furthermore, the findings of similar translatory tibiofemoral motion between groups suggest that self-reports of episodic joint instability in individuals with knee osteoarthritis may not necessarily be associated with adaptive alterations in joint arthrokinematics. PMID:22071429

Are the kinematics of the knee joint altered during the loading response phase of gait in individuals with concurrent knee osteoarthritis and complaints of joint instability? A dynamic stereo X-ray study.

Science.gov (United States)

Farrokhi, Shawn; Tashman, Scott; Gil, Alexandra B; Klatt, Brian A; Fitzgerald, G Kelley

2012-05-01

Joint instability has been suggested as a risk factor for knee osteoarthritis and a cause of significant functional decline in those with symptomatic disease. However, the relationship between altered knee joint mechanics and self-reports of instability in individuals with knee osteoarthritis remains unclear. Fourteen subjects with knee osteoarthritis and complaints of joint instability and 12 control volunteers with no history of knee disease were recruited for this study. Dynamic stereo X-ray technology was used to assess the three-dimensional kinematics of the knee joint during the loading response phase of gait. Individuals with concurrent knee osteoarthritis and joint instability demonstrated significantly reduced flexion and internal/external rotation knee motion excursions during the loading response phase of gait (Pknee joint at initial contact was significantly different (Pknee osteoarthritis and joint instability. However, the anteroposterior and mediolateral tibiofemoral joint positions at initial contact and the corresponding total joint translations were similar between groups during the loading phase of gait. The rotational patterns of tibiofemoral joint motion and joint alignments reported for individuals with concurrent knee osteoarthritis and joint instability are consistent with those previously established for individuals with knee osteoarthritis. Furthermore, the findings of similar translatory tibiofemoral motion between groups suggest that self-reports of episodic joint instability in individuals with knee osteoarthritis may not necessarily be associated with adaptive alterations in joint arthrokinematics. Copyright © 2011 Elsevier Ltd. All rights reserved.

Radiographic changes and factors associated with subsequent progression of damage in weight-bearing joints of patients with rheumatoid arthritis under TNF-blocking therapies-three-year observational study.

Science.gov (United States)

Matsushita, Isao; Motomura, Hiraku; Seki, Eiko; Kimura, Tomoatsu

2017-07-01

The long-term effects of tumor necrosis factor (TNF)-blocking therapies on weight-bearing joints in patients with rheumatoid arthritis (RA) have not been fully characterized. The purpose of this study was to assess the radiographic changes of weight-bearing joints in patients with RA during 3-year of TNF-blocking therapies and to identify factors related to the progression of joint damage. Changes in clinical variables and radiological findings in 243 weight-bearing joints (63 hips, 54 knees, 71 ankles, and 55 subtalar joints) in 38 consecutive patients were investigated during three years of treatment with TNF-blocking agents. Multivariate logistic regression analysis was used to identify risk factors for the progression of weight-bearing joint damage. Seventeen (14.5%) of proximal weight-bearing joints (hips and knees) showed apparent radiographic progression during three years of treatment, whereas none of the proximal weight-bearing joints showed radiographic evidence of improvement or repair. In contrast, distal weight-bearing joints (ankle and subtalar joints) displayed radiographic progression and improvement in 20 (15.9%) and 8 (6.3%) joints, respectively. Multivariate logistic analysis for proximal weight-bearing joints identified the baseline Larsen grade (p bearing joints identified disease activity at one year after treatment (p bearing joints. Disease activity after treatment was an independent factor for progression of damage in proximal and distal weight-bearing joints. Early treatment with TNF-blocking agents and tight control of disease activity are necessary to prevent the progression of damage of the weight-bearing joints.

Collision avoidance during teleoperation using whole arm proximity sensors coupled to a virtual environment

International Nuclear Information System (INIS)

Novak, J.L.; Feddema, J.T.; Miner, N.E.; Stansfield, S.A.

1993-01-01

Much of the current robotics effort at the US DOE is directed toward remote handling of hazardous waste. Telerobotic systems are being developed to remotely inspect, characterize, and process waste. This paper describes a collision avoidance system using Whole Arm Proximity (WHAP) sensors on an articulated robot arm. The capacitance-based sensors generate electric fields which completely encompass the robot arm and detect obstacles as they approach from any direction. The robot is moved through the workspace using a velocity command generated either by an operator through a force-sensing input device or a preprogrammed sequence of motions. The directional obstacle information gathered by the WHAP sensors is then used in a matrix column maximization algorithm that automatically selects the sensor closest to an obstacle during each robot controller cycle. The distance from this sensor to the obstacle is used to reduce the component of the command input velocity along the normal axis of the sensor, allowing graceful perturbation of the velocity command to prevent a collision. By scaling only the component of the velocity vector in the direction of the nearest obstacle, the control system restricts motion in the direction of an obstacle while permitting unconstrained motion in other directions. The actual robot joint positions and the WHAP sensor readings are communicated to an operator interface consisting of a graphical model of the Puma robot and its environment. Circles are placed on the graphical robot surface at positions corresponding to the locations of the WHAP sensor. As the individual sensors detect obstacles, the associated circles change color, providing the operator with visual feedback as to the location and relative size of the obstacle. At the same time, the graphical robot position is updated to reflect the actual state of the robot. This information permits the operator to plan alternative paths around unmodeled, but sensed, obstacles

Real-Time Motion Management of Prostate Cancer Radiotherapy

DEFF Research Database (Denmark)

Pommer, Tobias

, and for prostate cancer treatments, the proximity of the bladder and rectum makes radiotherapy treatment of this site a challenging task. Furthermore, the prostate may move during the radiation delivery and treatment margins are necessary to ensure that it is still receiving the intended dose. The main aim...... of the MLC on the performance of DMLC tracking were investigated. We found that for prostate motion, the main tracking error arose from the finite leaf width affecting the MLCs ability to construct the desired shape. Furthermore, we also attempted to model prostate motion using a random walk model. We found...... that for the slow and drifting motion, the model could satisfactory replicate the motion of the prostate, while the rapid and transient prostate motion observed in some cases was challenging for the model. We therefore added simulated transient motion to the random walk model, which slightly improved the results...

Ultrasonographic assessment of the proximal digital annular ligament in the equine forelimb

International Nuclear Information System (INIS)

Dik, K.J.; Boroffka, S.; Stolk, P.

1994-01-01

Ultrasonography was used with 6 normal cadaver forelimbs of Dutch Warmblood horses to delineate the ultrasonographic anatomy of the palmar pastern region, with emphasis on the proximal digital annular ligament. Using a 5.5 MHz sector scanner, the thin proximal digital annular ligament was not visible on offset sonograms. Only if the digital sheath in the normal limb was distended was the distal border of this ligament outlined. In all normal limbs the palmarodistal thickness of the combined skin-proximal digital annular ligament layer in the mid-pastern region was 2 mm. The flexor tendons and distal sesamoidean ligaments were easily identified as hyperechoic structures. Distension of the digital sheath in the normal limbs clearly outlined the anechoic digital sheath pouches. In 4 lame horses ultrasonography aided the diagnosis of functional proximal digital annular ligament constriction. In all 4 diseased forelimbs ultrasonography demonstrated thickening of the skin-proximal digital annular ligament layer and distension of the digital sheath. In one of these limbs the distended digital sheath was also thickened. The flexor tendons and distal sesamoidean ligaments were normal. There was no radiographic evidence of additional bone or joint lesions

Ultrasonographic assessment of the proximal digital annular ligament in the equine forelimb.

Science.gov (United States)

Dik, K J; Boroffka, S; Stolk, P

1994-01-01

Ultrasonography was used with 6 normal cadaver forelimbs of Dutch Warmblood horses to delineate the ultrasonographic anatomy of the palmar pastern region, with emphasis on the proximal digital annular ligament. Using a 5.5 MHz sector scanner, the thin proximal digital annular ligament was not visible on offset sonograms. Only if the digital sheath in the normal limb was distended was the distal border of this ligament outlined. In all normal limbs the palmarodistal thickness of the combined skin-proximal digital annular ligament layer in the mid-pastern region was 2 mm. The flexor tendons and distal sesamoidean ligaments were easily identified as hyperechoic structures. Distension of the digital sheath in the normal limbs clearly outlined the anechoic digital sheath pouches. In 4 lame horses ultrasonography aided the diagnosis of functional proximal digital annular ligament constriction. In all 4 diseased forelimbs ultrasonography demonstrated thickening of the skin-proximal digital annular ligament layer and distension of the digital sheath. In one of these limbs the distended digital sheath was also thickened. The flexor tendons and distal sesamoidean ligaments were normal. There was no radiographic evidence of additional bone or joint lesions.

Proximal Opening Wedge Osteotomy Provides Satisfactory Midterm Results With a Low Complication Rate.

Science.gov (United States)

Oravakangas, Rami; Leppilahti, Juhana; Laine, Vesa; Niinimäki, Tuukka

2016-01-01

Hallux valgus is one of the most common foot deformities. Proximal opening wedge osteotomy is used for the treatment of moderate and severe hallux valgus with metatarsus primus varus. However, hypermobility of the first tarsometatarsal joint can compromise the results of the operation, and a paucity of midterm results are available regarding proximal open wedge osteotomy surgery. The aim of the present study was to assess the midterm results of proximal open wedge osteotomy in a consecutive series of patients with severe hallux valgus. Thirty-one consecutive adult patients (35 feet) with severe hallux valgus underwent proximal open wedge osteotomy. Twenty patients (35.5%) and 23 feet (34.3%) were available for the final follow-up examination. The mean follow-up duration was 5.8 (range 4.6 to 7.0) years. The radiologic measurements and American Orthopaedic Foot and Ankle Society hallux-metatarsophalangeal-interphalangeal scores were recorded pre- and postoperatively, and subjective questionnaires were completed and foot scan analyses performed at the end of the follow-up period. The mean hallux valgus angle decreased from 38° to 23°, and the mean intermetatarsal angle correction decreased from 17° to 10°. The mean improvement in the American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal-interphalangeal score increased from 52 to 84. Two feet (5.7%) required repeat surgery because of recurrent hallux valgus. No nonunions were identified. Proximal open wedge osteotomy provided satisfactory midterm results in the treatment of severe hallux valgus, with a low complication rate. The potential instability of the first tarsometatarsal joint does not seem to jeopardize the midterm results of the operation. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

A reduced-dimensionality approach to uncovering dyadic modes of body motion in conversations.

Science.gov (United States)

Gaziv, Guy; Noy, Lior; Liron, Yuvalal; Alon, Uri

2017-01-01

Face-to-face conversations are central to human communication and a fascinating example of joint action. Beyond verbal content, one of the primary ways in which information is conveyed in conversations is body language. Body motion in natural conversations has been difficult to study precisely due to the large number of coordinates at play. There is need for fresh approaches to analyze and understand the data, in order to ask whether dyads show basic building blocks of coupled motion. Here we present a method for analyzing body motion during joint action using depth-sensing cameras, and use it to analyze a sample of scientific conversations. Our method consists of three steps: defining modes of body motion of individual participants, defining dyadic modes made of combinations of these individual modes, and lastly defining motion motifs as dyadic modes that occur significantly more often than expected given the single-person motion statistics. As a proof-of-concept, we analyze the motion of 12 dyads of scientists measured using two Microsoft Kinect cameras. In our sample, we find that out of many possible modes, only two were motion motifs: synchronized parallel torso motion in which the participants swayed from side to side in sync, and still segments where neither person moved. We find evidence of dyad individuality in the use of motion modes. For a randomly selected subset of 5 dyads, this individuality was maintained for at least 6 months. The present approach to simplify complex motion data and to define motion motifs may be used to understand other joint tasks and interactions. The analysis tools developed here and the motion dataset are publicly available.

Articular surface approximation in equivalent spatial parallel mechanism models of the human knee joint: an experiment-based assessment.

Science.gov (United States)

Ottoboni, A; Parenti-Castelli, V; Sancisi, N; Belvedere, C; Leardini, A

2010-01-01

In-depth comprehension of human joint function requires complex mathematical models, which are particularly necessary in applications of prosthesis design and surgical planning. Kinematic models of the knee joint, based on one-degree-of-freedom equivalent mechanisms, have been proposed to replicate the passive relative motion between the femur and tibia, i.e., the joint motion in virtually unloaded conditions. In the mechanisms analysed in the present work, some fibres within the anterior and posterior cruciate and medial collateral ligaments were taken as isometric during passive motion, and articulating surfaces as rigid. The shapes of these surfaces were described with increasing anatomical accuracy, i.e. from planar to spherical and general geometry, which consequently led to models with increasing complexity. Quantitative comparison of the results obtained from three models, featuring an increasingly accurate approximation of the articulating surfaces, was performed by using experimental measurements of joint motion and anatomical structure geometries of four lower-limb specimens. Corresponding computer simulations of joint motion were obtained from the different models. The results revealed a good replication of the original experimental motion by all models, although the simulations also showed that a limit exists beyond which description of the knee passive motion does not benefit considerably from further approximation of the articular surfaces.

Motion Simulation of a New Ankle Rehabilitation Device

Directory of Open Access Journals (Sweden)

Cristina Racu (Cazacu

2016-06-01

Full Text Available The ankle structure holds one of the most important role in the human biomechanics. Due to complexity of everyday activities this joint is the most prone to be injured part of the lower limb. For a complete recovery of the locomotion function, recovery exercises are mandatory. The introduction of robotic physical recovery systems represents a modern alternative to traditional recovery. Based on the 3D virtual model and a previous dimensional synthesis of a new ankle rehabilitation device, its motion simulation is presented in this paper, to prove that it may fully recover the range of motion required for this joint.

Using the American alligator and a repeated-measures design to place constraints on in vivo shoulder joint range of motion in dinosaurs and other fossil archosaurs.

Science.gov (United States)

Hutson, Joel D; Hutson, Kelda N

2013-01-15

Using the extant phylogenetic bracket of dinosaurs (crocodylians and birds), recent work has reported that elbow joint range of motion (ROM) studies of fossil dinosaur forearms may be providing conservative underestimates of fully fleshed in vivo ROM. As humeral ROM occupies a more central role in forelimb movements, the placement of quantitative constraints on shoulder joint ROM could improve fossil reconstructions. Here, we investigated whether soft tissues affect the more mobile shoulder joint in the same manner in which they affect elbow joint ROM in an extant archosaur. This test involved separately and repeatedly measuring humeral ROM in Alligator mississippiensis as soft tissues were dissected away in stages to bare bone. Our data show that the ROMs of humeral flexion and extension, as well as abduction and adduction, both show a statistically significant increase as flesh is removed, but then decrease when the bones must be physically articulated and moved until they separate from one another and/or visible joint surfaces. A similar ROM pattern is inferred for humeral pronation and supination. All final skeletonized ROMs were less than initial fully fleshed ROMs. These results are consistent with previously reported elbow joint ROM patterns from the extant phylogenetic bracket of dinosaurs. Thus, studies that avoid separation of complementary articular surfaces may be providing fossil shoulder joint ROMs that underestimate in vivo ROM in dinosaurs, as well as other fossil archosaurs.

Rhythmic Extended Kalman Filter for Gait Rehabilitation Motion Estimation and Segmentation.

Science.gov (United States)

Joukov, Vladimir; Bonnet, Vincent; Karg, Michelle; Venture, Gentiane; Kulic, Dana

2018-02-01

This paper proposes a method to enable the use of non-intrusive, small, wearable, and wireless sensors to estimate the pose of the lower body during gait and other periodic motions and to extract objective performance measures useful for physiotherapy. The Rhythmic Extended Kalman Filter (Rhythmic-EKF) algorithm is developed to estimate the pose, learn an individualized model of periodic movement over time, and use the learned model to improve pose estimation. The proposed approach learns a canonical dynamical system model of the movement during online observation, which is used to accurately model the acceleration during pose estimation. The canonical dynamical system models the motion as a periodic signal. The estimated phase and frequency of the motion also allow the proposed approach to segment the motion into repetitions and extract useful features, such as gait symmetry, step length, and mean joint movement and variance. The algorithm is shown to outperform the extended Kalman filter in simulation, on healthy participant data, and stroke patient data. For the healthy participant marching dataset, the Rhythmic-EKF improves joint acceleration and velocity estimates over regular EKF by 40% and 37%, respectively, estimates joint angles with 2.4° root mean squared error, and segments the motion into repetitions with 96% accuracy.

Evaluation of effects of different treatments for the wrist joints of subdominant hands using joint proprioception and writing time.

Science.gov (United States)

Hu, Chunying; Huang, Qiuchen; Yu, Lili; Hu, Yue; Rongming, Xia; Li, Zhou; Xiaojiao, Fu; Gu, Rui; Cui, Yao; Ge, Meng; Xu, Yanfeng; Liu, Jianfeng

2016-05-01

[Purpose] The purpose of this study was to examine immediate effects of strength training and NJF distal resistance training in wrist joints by using writing time and evaluation of proprioception using the JPE test. [Subjects and Methods] The subjects were 12 young healthy people (24.2 ± 3.1 y, 169.7 ± 6.5 cm, 65.3 ± 12.6 kg). Two isotonic contraction techniques were applied on the wrist joint: wrist joint extension muscle strength training (MST) and the wrist joint extension pattern of NJF. The uppercase English alphabet writing time and joint position errors of the left upper limb were measured before and after one intervention session of MST and NJF. [Results] The decrease in errors in wrist extension angle repetition and the writing time represented the improvement resulting from NJF. [Conclusion] This result suggests that the subdominant hands wrist joint proprioception and writing function can be improved by NJF together with proximal resistance training.

Active joint mechanism driven by multiple actuators made of flexible bags: a proposal of dual structural actuator.

Science.gov (United States)

Kimura, Hitoshi; Matsuzaki, Takuya; Kataoka, Mokutaro; Inou, Norio

2013-01-01

An actuator is required to change its speed and force depending on the situation. Using multiple actuators for one driving axis is one of the possible solutions; however, there is an associated problem of output power matching. This study proposes a new active joint mechanism using multiple actuators. Because the actuator is made of a flexible bag, it does not interfere with other actuators when it is depressurized. The proposed joint achieved coordinated motion of multiple actuators. This report also discusses a new actuator which has dual cylindrical structure. The cylinders are composed of flexible bags with different diameters. The joint torque is estimated based on the following factors: empirical formula for the flexible actuator torque, geometric relationship between the joint and the actuator, and the principle of virtual work. The prototype joint mechanism achieves coordinated motion of multiple actuators for one axis. With this motion, small inner actuator contributes high speed motion, whereas large outer actuator generates high torque. The performance of the prototype joint is examined by speed and torque measurements. The joint showed about 30% efficiency at 2.0 Nm load torque under 0.15 MPa air input.

Proximal iliotibial band syndrome: case report

Directory of Open Access Journals (Sweden)

Guilherme Guadagnini Falotico

2013-08-01

Full Text Available OBJECTIVE: The overuse injuries in the hip joint occur commonly in sports practitioners and currently due to technical advances in diagnostic imaging, especially magnetic resonance imaging (MRI, are often misdiagnosed. Recently, a group of people were reported, all female, with pain and swelling in the pelvic region.T2-weighted MRI showed increased signal in the enthesis of the iliotibial band (ITB along the lower border of the iliac tubercle. We report a case of a 34 year old woman, non-professional runner, with pain at the iliac crest with no history of trauma and whose MRI was compatible with the proximal iliotibial band syndrome.

Comparison of Photo Optical Imaging with Musculoskeletal Ultrasound and Clinical Examination in the Assessment of Inflammatory Activity in Proximal Interphalangeal Joints in Rheumatoid Arthritis and Osteoarthritis.

Science.gov (United States)

Amitai, Isabella; Werner, Stephanie; Schicke, Bernd; Burmester, Gerd-Rüdiger; Minet, Olaf; Zabaryło, Urszula; Backhaus, Marina; Ohrndorf, Sarah

2015-09-01

Lightscan is a novel, rapid, low-cost, easily operated and noninvasive imaging technology used to assess inflammatory activity in proximal interphalangeal (PIP) joints. The results are calculated automatically. To our knowledge, this is the first comparative study of photo optical imaging (POI), with clinical examination (CE), disease activity score at 28 joints (DAS28)-erythrocyte sedimentation rate (ESR), and musculoskeletal ultrasonography (US) in healthy subjects and patients with rheumatoid arthritis (RA) or osteoarthritis (OA). There were 688 PIP joints of both hands examined in 87 subjects (38 RA, 21 OA, 28 healthy) by Lightscan and compared with CE for clinically swollen and tender joints, DAS28-ESR (only RA), and US. With US as reference, POI had a sensitivity of 74% and a specificity of 93%. In the receiver-operating curve (ROC) analysis, the Lightscan showed a higher sensitivity and specificity [area under the curve (AUC) 0.879] for the distinction of healthy subjects versus patients (OA, RA) than US in greyscale (GSUS; AUC 0.797) and power Doppler (PDUS; AUC 0.67). POI correlated significantly with GSUS (r 0.473, p POI and GSUS were up to 79%, between POI and PDUS up to 92%, and between POI and CE up to 66%. POI did not correlate with DAS28-ESR. The Lightscan is a new technology offering sensitive imaging detection of inflammatory changes in subjects with RA and OA with PIP arthritis. POI was more sensitive than CE and correlated significantly to GSUS and PDUS, while presenting a higher sensitivity and specificity for the detection of healthy subjects versus patients (RA, OA) based on the ROC analysis.

Effects of neuromuscular fatigue on perceptual-cognitive skills between genders in the contribution to the knee joint loading during side-stepping tasks.

Science.gov (United States)

Khalid, Abdul Jabbar; Harris, Sujae Ian; Michael, Loke; Joseph, Hamill; Qu, Xingda

2015-01-01

This study investigated whether neuromuscular fatigue affects the neuromuscular control of an athlete within a sports context setting and whether these effects were more pronounced in the females. Lower limb joint kinetics of 6 male and 6 female inter-varsity soccer players performing side-stepping tasks in non-fatigue versus fatigue and anticipated versus unanticipated conditions were quantified using 10 Motion Analysis Corporation cameras and a Kistler(™) force platform. The Yo-Yo intermittent recovery Level 1 fatigue protocol was employed. Stance foot initial contact and peak forces, and peak joint knee moments of the lower limb were submitted to a 3-way mixed-model repeated measure ANOVA. The results suggested that males tend to elicit significantly higher knee joint loadings when fatigued. In addition, males elicited significantly higher peak proximal tibia anterior/posterior shear force, vertical ground reaction force at initial contact and peak internal rotational moments than females. These findings suggested that males were at greater overall injury risk than females, especially in the sagittal plane. Neuromuscular control-based training programmes/interventions that are designed to reduce the risk of the non-contact ACL injury need to be customised for the different genders.

Management of acromioclavicular joint injuries.

Science.gov (United States)

Li, Xinning; Ma, Richard; Bedi, Asheesh; Dines, David M; Altchek, David W; Dines, Joshua S

2014-01-01

Acromioclavicular joint injuries are among the most common shoulder girdle injuries in athletes and most commonly result from a direct force to the acromion with the arm in an adducted position. Acromioclavicular joint injuries often present with associated injuries to the glenohumeral joint, including an increased incidence of superior labrum anterior posterior (SLAP) tears that may warrant further evaluation and treatment. Anteroposterior stability of the acromioclavicular joint is conferred by the capsule and acromioclavicular ligaments, of which the posterior and superior ligaments are the strongest. Superior-inferior stability is maintained by the coracoclavicular (conoid and trapezoid) ligaments. Type-I or type-II acromioclavicular joint injuries have been treated with sling immobilization, early shoulder motion, and physical therapy, with favorable outcomes. Return to activity can occur when normal shoulder motion and strength are obtained and the shoulder is asymptomatic as compared with the contralateral normal extremity. The management of type-III injuries remains controversial and is individualized. While a return to the previous level of functional activity with nonsurgical treatment has been documented in a number of case series, surgical reduction and coracoclavicular ligament reconstruction has been associated with a favorable outcome and can be considered in patients who place high functional demands on their shoulders or in athletes who participate in overhead sports. Surgical management is indicated for high-grade (≥type IV) acromioclavicular joint injuries to achieve anatomic reduction of the acromioclavicular joint, reconstruction of the coracoclavicular ligaments, and repair of the deltotrapezial fascia. Outcomes after surgical reconstruction of the coracoclavicular ligaments have been satisfactory with regard to achieving pain relief and return to functional activities, but further improvements in the biomechanical strength of these

Conceptualization of an exoskeleton Continuous Passive Motion(CPM) device using a link structure.

Science.gov (United States)

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. © 2011 IEEE

Low-Friction, Low-Profile, High-Moment Two-Axis Joint

Science.gov (United States)

Lewis, James L.; Le, Thang; Carroll, Monty B.

2010-01-01

The two-axis joint is a mechanical device that provides two-degrees-of-freedom motion between connected components. A compact, moment-resistant, two-axis joint is used to connect an electromechanical actuator to its driven structural members. Due to the requirements of the overall mechanism, the joint has a low profile to fit within the allowable space, low friction, and high moment-reacting capability. The mechanical arrangement of this joint can withstand high moments when loads are applied. These features allow the joint to be used in tight spaces where a high load capability is required, as well as in applications where penetrating the mounting surface is not an option or where surface mounting is required. The joint consists of one base, one clevis, one cap, two needle bearings, and a circular shim. The base of the joint is the housing (the base and the cap together), and is connected to the grounding structure via fasteners and a bolt pattern. Captive within the housing, between the base and the cap, are the rotating clevis and the needle bearings. The clevis is attached to the mechanical system (linear actuator) via a pin. This pin, and the rotational movement of the clevis with respect to the housing, provides two rotational degrees of freedom. The larger diameter flange of the clevis is sandwiched between a pair of needle bearings, one on each side of the flange. During the assembly of the two-axis joint, the circular shims are used to adjust the amount of preload that is applied to the needle bearings. The above arrangement enables the joint to handle high moments with minimal friction. To achieve the high-moment capability within a low-profile joint, the use of depth of engagement (like that of a conventional rotating shaft) to react moment is replaced with planar engagement parallel to the mounting surface. The needle bearings with the clevis flange provide the surface area to react the clevis loads/moments into the joint housing while providing minimal

INTER-JOINT COORDINATION IN PRODUCING KICKING VELOCITY OF TAEKWONDO KICKS

Directory of Open Access Journals (Sweden)

Young Kwan Kim

2011-03-01

Full Text Available The purpose of this study was to investigate joint kinematics of the kicking leg in Taekwondo and to examine the role of inter-joint coordination of the leg in producing the kicking velocity. A new inter-joint coordination index that encompasses three- dimensional hip and knee motions, was defined and applied to the joint kinematic results. Twelve elite Taekwondo athletes participated in this study and performed the back kick, thrashing kick, turning-back kick and roundhouse kick. Our results indicate that the back kick utilized a combination of hip and knee extension to produce the kicking velocity, and was characterized by a pushlike movement. The thrashing kick and turning-back kick utilized a greater degree of hip abduction than the roundhouse kick and back kick, and included complicated knee motions. The new index successfully categorized the thrashing kick and turning-back kick into a push-throw continuum, indicating a change from negative index (opposite direction to positive index (same direction of hip and knee motions at the end of the movement. This strategy of push-throw continuum increases the kicking velocity at the moment of impact by applying a throwlike movement pattern

Joint Center Estimation Using Single-Frame Optimization: Part 1: Numerical Simulation

OpenAIRE

Eric Frick; Salam Rahmatalla

2018-01-01

The biomechanical models used to refine and stabilize motion capture processes are almost invariably driven by joint center estimates, and any errors in joint center calculation carry over and can be compounded when calculating joint kinematics. Unfortunately, accurate determination of joint centers is a complex task, primarily due to measurements being contaminated by soft-tissue artifact (STA). This paper proposes a novel approach to joint center estimation implemented via sequential applic...

Statistical Parametric Mapping to Identify Differences between Consensus-Based Joint Patterns during Gait in Children with Cerebral Palsy.

Science.gov (United States)

Nieuwenhuys, Angela; Papageorgiou, Eirini; Desloovere, Kaat; Molenaers, Guy; De Laet, Tinne

2017-01-01

Experts recently identified 49 joint motion patterns in children with cerebral palsy during a Delphi consensus study. Pattern definitions were therefore the result of subjective expert opinion. The present study aims to provide objective, quantitative data supporting the identification of these consensus-based patterns. To do so, statistical parametric mapping was used to compare the mean kinematic waveforms of 154 trials of typically developing children (n = 56) to the mean kinematic waveforms of 1719 trials of children with cerebral palsy (n = 356), which were classified following the classification rules of the Delphi study. Three hypotheses stated that: (a) joint motion patterns with 'no or minor gait deviations' (n = 11 patterns) do not differ significantly from the gait pattern of typically developing children; (b) all other pathological joint motion patterns (n = 38 patterns) differ from typically developing gait and the locations of difference within the gait cycle, highlighted by statistical parametric mapping, concur with the consensus-based classification rules. (c) all joint motion patterns at the level of each joint (n = 49 patterns) differ from each other during at least one phase of the gait cycle. Results showed that: (a) ten patterns with 'no or minor gait deviations' differed somewhat unexpectedly from typically developing gait, but these differences were generally small (≤3°); (b) all other joint motion patterns (n = 38) differed from typically developing gait and the significant locations within the gait cycle that were indicated by the statistical analyses, coincided well with the classification rules; (c) joint motion patterns at the level of each joint significantly differed from each other, apart from two sagittal plane pelvic patterns. In addition to these results, for several joints, statistical analyses indicated other significant areas during the gait cycle that were not included in the pattern definitions of the consensus study

The Rendezvous Monitoring Display Capabilities of the Rendezvous and Proximity Operations Program

Science.gov (United States)

Brazzel, Jack; Spehar, Pete; Clark, Fred; Foster, Chris; Eldridge, Erin

2013-01-01

The Rendezvous and Proximity Operations Program (RPOP) is a laptop computer- based relative navigation tool and piloting aid that was developed during the Space Shuttle program. RPOP displays a graphical representation of the relative motion between the target and chaser vehicles in a rendezvous, proximity operations and capture scenario. After being used in over 60 Shuttle rendezvous missions, some of the RPOP display concepts have become recognized as a minimum standard for cockpit displays for monitoring the rendezvous task. To support International Space Station (ISS) based crews in monitoring incoming visiting vehicles, RPOP has been modified to allow crews to compare the Cygnus visiting vehicle s onboard navigated state to processed range measurements from an ISS-based, crew-operated Hand Held Lidar sensor. This paper will discuss the display concepts of RPOP that have proven useful in performing and monitoring rendezvous and proximity operations.

Evaluation of segmental left ventricular wall motion by equilibrium gated radionuclide ventriculography.

Science.gov (United States)

Van Nostrand, D; Janowitz, W R; Holmes, D R; Cohen, H A

1979-01-01

The ability of equilibrium gated radionuclide ventriculography to detect segmental left ventricular (LV) wall motion abnormalities was determined in 26 patients undergoing cardiac catheterization. Multiple gated studies obtained in 30 degrees right anterior oblique and 45 degrees left anterior oblique projections, played back in a movie format, were compared to the corresponding LV ventriculograms. The LV wall in the two projections was divided into eight segments. Each segment was graded as normal, hypokinetic, akinetic, dyskinetic, or indeterminate. Thirteen percent of the segments in the gated images were indeterminate; 24 out of 27 of these were proximal or distal inferior wall segments. There was exact agreement in 86% of the remaining segments. The sensitivity of the radionuclide technique for detecting normal versus any abnormal wall motion was 71%, with a specificity of 99%. Equilibrium gated ventriculography is an excellent noninvasive technique for evaluating segmental LV wall motion. It is least reliable in assessing the proximal inferior wall and interventricular septum.

Prevention of the Post-traumatic Fibrotic Response in Joints

Science.gov (United States)

2014-10-01

The American journal of forensic medicine and pathology . 1988; 9(4):310-2. 14 APPENDICES: An abstract submitted for the ORS conference...clinical problem of posttraumatic joint stiffness, a pathology that reduces the range of motion (ROM) of injured joints and contributes to the...development of osteoarthritis. The fundamental hypothesis that drives the current study is that pathological fibrotic response of injured joint tissues

Distal radioulnar joint injuries

Directory of Open Access Journals (Sweden)

Binu P Thomas

2012-01-01

Full Text Available Distal radioulnar joint is a trochoid joint relatively new in evolution. Along with proximal radioulnar joint , forearm bones and interosseous membrane, it allows pronosupination and load transmission across the wrist. Injuries around distal radioulnar joint are not uncommon, and are usually associated with distal radius fractures,fractures of the ulnar styloid and with the eponymous Galeazzi or Essex_Lopresti fractures. The injury can be purely involving the soft tissue especially the triangular fibrocartilage or the radioulnar ligaments.The patients usually present with ulnar sided wrist pain, features of instability, or restriction of rotation. Difficulty in carrying loads in the hand is a major constraint for these patients. Thorough clinical examination to localize point of tenderness and appropriate provocative tests help in diagnosis. Radiology and MRI are extremely useful, while arthroscopy is the gold standard for evaluation. The treatment protocols are continuously evolving and range from conservative, arthroscopic to open surgical methods. Isolated dislocation are uncommon. Basal fractures of the ulnar styloid tend to make the joint unstable and may require operative intervention. Chronic instability requires reconstruction of the stabilizing ligaments to avoid onset of arthritis. Prosthetic replacement in arthritis is gaining acceptance in the management of arthritis.

Neuromuscular properties of different spastic human joints vary systematically.

Science.gov (United States)

Mirbagheri, M M; Settle, K

2010-01-01

We quantified the mechanical abnormalities of the spastic wrist in chronic stroke survivors, and determined whether these findings were representative of those recorded at the elbow and ankle joints. System identification techniques were used to characterize the mechanical abnormalities of these joints and to identify the contribution of intrinsic and reflex stiffness to these abnormalities. Modulation of intrinsic and reflex stiffness with the joint angle was studied by applying PRBS perturbations to the joints at different joint angles over the range of motion. Age-matched healthy subjects were used as control.

Evaluation of an Image-Based Tool to Examine the Effect of Fracture Alignment and Joint Congruency on Outcomes after Wrist Fracture.

Science.gov (United States)

Lalone, Emily A; Grewal, Ruby; King, Graham W; MacDermid, Joy C

2015-01-01

Some mal-alignment of the wrist occurs in up to 71% of patients following a distal radius fracture. A multiple case study was used to provide proof of principle of an image-based technique to investigate the evolution and impact of post-traumatic joint changes at the distal radioulnar joint. Participants who had a unilateral distal radius fracture who previously participated in a prospective study were recruited from a single tertiary hand center. Long term follow-up measures of pain, disability, range of motion and radiographic alignment were obtained and compared to joint congruency measures. The inter-bone distance, a measure of joint congruency was quantified from reconstructed CT bone models of the distal radius and ulna and the clinical outcome was quantified using the patient rated wrist evaluation. In all four cases, acceptable post-reduction alignment and minimal pain/disability at 1-year suggested good clinical outcomes. However, 10 years following injury, 3 out of 4 patients had radiographic signs of degenerative changes occurring in their injured wrist (distal radioulnar joint/radio-carpal joint). Proximity maps displaying inter-bone distances showed asymmetrical congruency between wrists in these three patients. The 10-year PRWE (patient rated wrist evaluation) varied from 4 to 60, with 3 reporting minimal pain/disability and one experiencing high pain/disability. These illustrative cases demonstrate long-term joint damage post-fracture is common and occurs despite positive short-term clinical outcomes. Imaging and functional outcomes are not necessarily correlated. A novel congruency measure provides an indicator of the overall impact of joint mal-alignment that can be used to determine predictors of post-traumatic arthritis and is viable for clinical or large cohort studies.

Video super-resolution using simultaneous motion and intensity calculations

DEFF Research Database (Denmark)

Keller, Sune Høgild; Lauze, Francois Bernard; Nielsen, Mads

2011-01-01

for the joint estimation of a super-resolution sequence and its flow field. Via the calculus of variations, this leads to a coupled system of partial differential equations for image sequence and motion estimation. We solve a simplified form of this system and as a by-product we indeed provide a motion field...

A 3D motion planning framework for snake robots

OpenAIRE

Liljebäck, Pål; Pettersen, Kristin Ytterstad; Stavdahl, Øyvind; Gravdahl, Jan Tommy

2014-01-01

- Author's postprint This paper presents a motion planning framework for three-dimensional body shape control of snake robots. Whereas conventional motion planning approaches define the body shape of snake robots in terms of their individual joint angles, the proposed framework allows the body shape to be specified in terms of Cartesian coordinates in the environment of the robot. This approach simplifies motion planning since Cartesian coordinates are more intuitively mapped to the overal...

Short frontal plane fractures involving the dorsoproximal articular surface of the proximal phalanx: Description of the injury and a technique for repair.

Science.gov (United States)

Wright, I M; Minshall, G J

2018-01-01

Chip fractures of the dorsoproximal articular margin of the proximal phalanx are common injuries in racehorses. Large fractures can extend distal to the joint capsule insertion and have been described as dorsal frontal fractures. To report the location and morphology of short frontal plane fractures involving the dorsoproximal articular surface of the proximal phalanx and describe a technique for repair under arthroscopic and radiographic guidance. Single centre retrospective case study. Case records of horses with frontal plane fractures restricted to the dorsoproximal epiphysis and metaphysis of the proximal phalanx referred to Newmarket Equine Hospital were retrieved, images reviewed and lesion morphology described. A technique for repair and the results obtained are reported. A total of 22 fractures in 21 horses commencing at the proximal articular surface exited the dorsal cortex of the proximal phalanx distal to the metacarpophalangeal/metatarsophalangeal joint capsule in 17 hind- and five forelimbs. All were in Thoroughbred racehorses. In 16 cases these were acute racing or training injuries; 20 fractures were medial, one lateral and one was midline. All were repaired with a single lag screw using arthroscopic and radiographically determined landmarks. A total of 16 horses raced after surgery with performance data similar to their preinjury levels. The study demonstrates substantial morphological similarities between individual lesions supporting a common pathophysiology, but does not identify precise causation. There are no cases managed differently that might permit assessment of the comparative efficacy of the treatment described. Short frontal plane fractures involving the dorsoproximal margin of the proximal phalanx that exit the bone distal to the metacarpophalangeal/metatarsophalangeal joint capsule have substantial morphological similarities, are amenable to minimally invasive repair and carry a good prognosis for return to training and racing. �

Kinematics Simulation Analysis of Packaging Robot with Joint Clearance

Science.gov (United States)

Zhang, Y. W.; Meng, W. J.; Wang, L. Q.; Cui, G. H.

2018-03-01

Considering the influence of joint clearance on the motion error, repeated positioning accuracy and overall position of the machine, this paper presents simulation analysis of a packaging robot — 2 degrees of freedom(DOF) planar parallel robot based on the characteristics of high precision and fast speed of packaging equipment. The motion constraint equation of the mechanism is established, and the analysis and simulation of the motion error are carried out in the case of turning the revolute clearance. The simulation results show that the size of the joint clearance will affect the movement accuracy and packaging efficiency of the packaging robot. The analysis provides a reference point of view for the packaging equipment design and selection criteria and has a great significance on the packaging industry automation.

Technical feasibility of personalized articulating knee joint distraction for treatment of tibiofemoral osteoarthritis.

Science.gov (United States)

Struik, T; Jaspers, J E N; Besselink, N J; van Roermund, P M; Plomp, S; Rudert, M J; Lafeber, F P J G; Mastbergen, S C

2017-11-01

Knee osteoarthritis is a highly prevalent degenerative joint disorder characterized by joint tissue damage and pain. Knee joint distraction has been introduced as a joint preserving surgical procedure to postpone knee arthroplasty. An often used standard externally fixation device for distraction poses a burden to patients due to the absence of joint flexion during the 6weeks treatment. Therefore, a personalized articulating distraction device was developed. The aim of this study was to test technical feasibility of this device. Based on an often applied rigid device, using equal bone pin positions and connectors, a hinge mechanism was developed consisting of a cam-following system for reproducing the complex joint-specific knee kinematics. In support, a device was developed for capturing the joint-specific sagittal plane articulation. The obtained kinematic data were translated into joint-specific cam shapes that were installed bilaterally in the hinge mechanism of the distraction device, as such providing personalized knee motion. Distraction of 5mm was performed within a range of motion of 30deg. joint flexion. Pre-clinical evaluation of the working principle was performed on human cadaveric legs and system stiffness characteristics were biomechanically evaluated. The desired range of motion was obtained and distraction was maintained under physiologically representative loading. Moreover, the joint-specific approach demonstrated tolerance of deviations from anatomical and alignment origin during initial placement of the developed distraction device. Articulation during knee distraction is considered technically feasible and has potential to decrease burden and improve acceptance of distraction therapy. Testing of clinical feasibility is warranted. Copyright © 2017 Elsevier Ltd. All rights reserved.

Thumb carpometacarpal joint congruence during functional tasks and thumb range-of-motion activities

Science.gov (United States)

Halilaj, Eni; Moore, Douglas C; Patel, Tarpit K; Laidlaw, David H; Ladd, Amy L; Weiss, Arnold-Peter C; Crisco, Joseph J

2017-01-01

Joint incongruity is often cited as a possible etiological factor for the high incidence of thumb carpometacarpal (CMC) joint osteoarthritis (OA) in older women. There is evidence suggesting that biomechanics plays a role in CMC OA progression, but little is known about how CMC joint congruence, specifically, differs among different cohorts. The purpose of this in vivo study was to determine if CMC joint congruence differs with sex, age, and early stage OA for different thumb positions. Using CT data from 155 subjects and a congruence metric that is based on both articular morphology and joint posture, we did not find any differences in CMC joint congruence with sex or age group, but found that patients in the early stages of OA exhibit lower congruence than healthy subjects of the same age group. PMID:25570956

Thumb carpometacarpal joint congruence during functional tasks and thumb range-of-motion activities.

Science.gov (United States)

Halilaj, Eni; Moore, Douglas C; Patel, Tarpit K; Laidlaw, David H; Ladd, Amy L; Weiss, Arnold-Peter C; Crisco, Joseph J

2014-01-01

Joint incongruity is often cited as a possible etiological factor for the high incidence of thumb carpometacarpal (CMC) joint osteoarthritis (OA) in older women. There is evidence suggesting that biomechanics plays a role in CMC OA progression, but little is known about how CMC joint congruence, specifically, differs among different cohorts. The purpose of this in vivo study was to determine if CMC joint congruence differs with sex, age, and early stage OA for different thumb positions. Using CT data from 155 subjects and a congruence metric that is based on both articular morphology and joint posture, we did not find any differences in CMC joint congruence with sex or age group, but found that patients in the early stages of OA exhibit lower congruence than healthy subjects of the same age group.

Development of osteochondrosis in the tarsocrural joint and osteochondral fragments in the fetlock joints of Standardbred trotters. I. A radiological survey

International Nuclear Information System (INIS)

Carlsten, J.; Sandgren, B.; Dalin, G.

1993-01-01

In a longitudinal study 77 Standardbred foals were examined 6 times from birth to the age of 16 months. The radiological examination included 9 views, selected to demonstrate the time of occurrence and the appearance of early radiographic signs of osteochondrosis in the tarsocrural joints (OC), palmar/plantar osteochondral fragments in the fetlock joints (POF) and ununited proximal palmar/plantar eminences of the proximal phalanx (UPE). Subchondral bone defects with a diameter >5 mm and/or osseous fragments were considered significant radiographic findings and were correlated to clinical signs.Eight horses (10.4%) showed OC in the tarsocrural joints at the age of 12 months. All 8 horses showed radiographic changes indicating early OC lesions that were detectable before the age of 3 months. In 4 of these horses subchondral bone defects and/or fragments at the intermediate ridge of the distal tibia were visible before 1 month of age. Eleven horses showed radiographic changes first detected between 1 and 3 months of age that reverted to normal appearance at 8 months of age. In no case was a significant radiographic finding first detected between the age of 8 and 16 months. The radiographic findings of permanent hock OC were significantly correlated with the presence of tarsocrural joint effusions but did not correlate with lameness.At the age of 12 months, 11 horses (14.3%) showed significant radiographic changes with defects and/or osseous fragments in the metacarpo- and metatarsophalangeal (fetlock) joints. In all of these horses early indications of these changes were detected before the age of 5 months. In 7 horses early radiographic signs of abnormal ossification reverted to a normal appearance before the age of 8 months. No additional significant radiographic findings were detected after the age of 8 months. There was no correlation between radiographic findings and fetlock joint synovial effusion or lameness.Osteochondrosis of the tarsocrural joints and palmar

[Augmentation technique on the proximal humerus].

Science.gov (United States)

Scola, A; Gebhard, F; Röderer, G

2015-09-01

The treatment of osteoporotic fractures is still a challenge. The advantages of augmentation with respect to primary in vitro stability and the clinical use for the proximal humerus are presented in this article. In this study six paired human humeri were randomized into an augmented and a non-augmented group. Osteosynthesis was performed with a PHILOS plate (Synthes®). In the augmented group the two screws finding purchase in the weakest cancellous bone were augmented. The specimens were tested in a 3-part fracture model in a varus bending test. The augmented PHILOS plates withstood significantly more load cycles until failure. The correlation to bone mineral density (BMD) showed that augmentation could partially compensate for low BMD. The augmentation of the screws in locked plating in a proximal humerus fracture model is effective in improving the primary stability in a cyclic varus bending test. The targeted augmentation of two particular screws in a region of low bone quality within the humeral head was almost as effective as four screws with twice the amount of bone cement. Screw augmentation combined with a knowledge of the local bone quality could be more effective in enhancing the primary stability of a proximal humerus locking plate because the effect of augmentation can be exploited more effectively limiting it to the degree required. The technique of augmentation is simple and can be applied in open and minimally invasive procedures. When the correct procedure is used, complications (cement leakage into the joint) can be avoided.

Estimation of ground reaction forces and joint moments on the basis on plantar pressure insoles and wearable sensors for joint angle measurement.

Science.gov (United States)

Ostaszewski, Michal; Pauk, Jolanta

2018-05-16

Gait analysis is a useful tool medical staff use to support clinical decision making. There is still an urgent need to develop low-cost and unobtrusive mobile health monitoring systems. The goal of this study was twofold. Firstly, a wearable sensor system composed of plantar pressure insoles and wearable sensors for joint angle measurement was developed. Secondly, the accuracy of the system in the measurement of ground reaction forces and joint moments was examined. The measurements included joint angles and plantar pressure distribution. To validate the wearable sensor system and examine the effectiveness of the proposed method for gait analysis, an experimental study on ten volunteer subjects was conducted. The accuracy of measurement of ground reaction forces and joint moments was validated against the results obtained from a reference motion capture system. Ground reaction forces and joint moments measured by the wearable sensor system showed a root mean square error of 1% for min. GRF and 27.3% for knee extension moment. The correlation coefficient was over 0.9, in comparison with the stationary motion capture system. The study suggests that the wearable sensor system could be recommended both for research and clinical applications outside a typical gait laboratory.

Elbow joint rehabilitation equipment actuated by pneumatic muscles

Directory of Open Access Journals (Sweden)

Vetrice Georgiana

2017-01-01

Full Text Available The mobility of the limbs is an essential prerequisite for the individual’s physical autonomy. For persons suffering from post-traumatic affections of the elbow joint such limited mobility results in barriers in fulfilling personal or professional tasks. Passive motion has certain specific advantages and beneficial effects, thus being highly recommended for the recovery of injured joints. The paper presents a model of rehabilitation equipment that induces continuous passive motion of the elbow, as part of a recovery programme. The equipment is actuated by pneumatic muscles, using compressed air as the source of energy that generates force and motion. The main benefits of the pneumatic actuation system compared to other driving systems are its low cost, simple and robust construction and swift response to commands. Its constructive simplicity and reduced cost adds to the system’s eligibility for deployment in medical units.

Sensing human hand motions for controlling dexterous robots

Science.gov (United States)

Marcus, Beth A.; Churchill, Philip J.; Little, Arthur D.

1988-01-01

The Dexterous Hand Master (DHM) system is designed to control dexterous robot hands such as the UTAH/MIT and Stanford/JPL hands. It is the first commercially available device which makes it possible to accurately and confortably track the complex motion of the human finger joints. The DHM is adaptable to a wide variety of human hand sizes and shapes, throughout their full range of motion.

Motion of a Rigid Body Supported at One Point by a Rotating Arm

Directory of Open Access Journals (Sweden)

Jeffrey D. Stoen

1993-01-01

Full Text Available This article details a scheme for evaluating the stability of motions of a system consisting of a rigid body connected at one point to a rotating arm. The nonlinear equations of motion for the system are formulated, and a method for finding exact solutions representing motions that resemble a state of rest is presented. The equations are then linearized and roots of the eigensystem are classified and used to construct stability diagrams that facilitate the assessment of effects of varying the body's mass properties and system geometry, changing the position of the attachment joint, and adding energy dissipation in the joint.

Effect of boot shaft stiffness on stability joint energy and muscular co-contraction during walking on uneven surface.

Science.gov (United States)

Böhm, Harald; Hösl, Matthias

2010-09-17

Increased boot shaft stiffness may have a noticeable impact on the range of motion of the ankle joint. Therefore, the ability of the ankle joint to generate power for propulsion might be impaired. This might result in compensatory changes at the knee and hip joint. Besides, adaptability of the subtalar joint to uneven surface might be reduced, which could in turn affect stability. The aim of the study was therefore to investigate the influence of boot shaft stiffness on biomechanical gait parameters. Fifteen healthy young adults walked over coarse gravel wearing two different hiking boots that differed by 50% in passive shaft stiffness. Leg kinematics, kinetics and electromyography were measured. Gait velocity and indicators for stability were not different when walking with the hard and soft boot shaft over the gravel surface. However, the hard boot shaft decreased the ankle range of motion as well as the eccentric energy absorbed at the ankle joint. As a consequence, compensatory changes at the knee joint were observed. Co-contraction was increased, and greater eccentric energy was absorbed. Therefore, the efficiency of gait with hard boots might be decreased and joint loading at the knee might be increased, which might cause early fatigue of knee muscles during walking or hiking. The results of this study suggest that stiffness and blocking of joint motion at the ankle should not be equated with safety. A trade-off between lateral stiffness and free natural motion of the ankle joint complex might be preferable.

Feasibility of Using Low-Cost Motion Capture for Automated Screening of Shoulder Motion Limitation after Breast Cancer Surgery.

Directory of Open Access Journals (Sweden)

Valeriya Gritsenko

Full Text Available To determine if a low-cost, automated motion analysis system using Microsoft Kinect could accurately measure shoulder motion and detect motion impairments in women following breast cancer surgery.Descriptive study of motion measured via 2 methods.Academic cancer center oncology clinic.20 women (mean age = 60 yrs were assessed for active and passive shoulder motions during a routine post-operative clinic visit (mean = 18 days after surgery following mastectomy (n = 4 or lumpectomy (n = 16 for breast cancer.Participants performed 3 repetitions of active and passive shoulder motions on the side of the breast surgery. Arm motion was recorded using motion capture by Kinect for Windows sensor and on video. Goniometric values were determined from video recordings, while motion capture data were transformed to joint angles using 2 methods (body angle and projection angle.Correlation of motion capture with goniometry and detection of motion limitation.Active shoulder motion measured with low-cost motion capture agreed well with goniometry (r = 0.70-0.80, while passive shoulder motion measurements did not correlate well. Using motion capture, it was possible to reliably identify participants whose range of shoulder motion was reduced by 40% or more.Low-cost, automated motion analysis may be acceptable to screen for moderate to severe motion impairments in active shoulder motion. Automatic detection of motion limitation may allow quick screening to be performed in an oncologist's office and trigger timely referrals for rehabilitation.

Feasibility of Using Low-Cost Motion Capture for Automated Screening of Shoulder Motion Limitation after Breast Cancer Surgery.

Science.gov (United States)

Gritsenko, Valeriya; Dailey, Eric; Kyle, Nicholas; Taylor, Matt; Whittacre, Sean; Swisher, Anne K

2015-01-01

To determine if a low-cost, automated motion analysis system using Microsoft Kinect could accurately measure shoulder motion and detect motion impairments in women following breast cancer surgery. Descriptive study of motion measured via 2 methods. Academic cancer center oncology clinic. 20 women (mean age = 60 yrs) were assessed for active and passive shoulder motions during a routine post-operative clinic visit (mean = 18 days after surgery) following mastectomy (n = 4) or lumpectomy (n = 16) for breast cancer. Participants performed 3 repetitions of active and passive shoulder motions on the side of the breast surgery. Arm motion was recorded using motion capture by Kinect for Windows sensor and on video. Goniometric values were determined from video recordings, while motion capture data were transformed to joint angles using 2 methods (body angle and projection angle). Correlation of motion capture with goniometry and detection of motion limitation. Active shoulder motion measured with low-cost motion capture agreed well with goniometry (r = 0.70-0.80), while passive shoulder motion measurements did not correlate well. Using motion capture, it was possible to reliably identify participants whose range of shoulder motion was reduced by 40% or more. Low-cost, automated motion analysis may be acceptable to screen for moderate to severe motion impairments in active shoulder motion. Automatic detection of motion limitation may allow quick screening to be performed in an oncologist's office and trigger timely referrals for rehabilitation.

Measuring implementation of a school-based violence prevention program : Fidelity and teachers' responsiveness as predictors of proximal outcomes

NARCIS (Netherlands)

Schultes, Marie Therese; Stefanek, Elisabeth; van de Schoot, Rens; Strohmeier, Dagmar; Spiel, Christiane

2014-01-01

When school-based prevention programs are put into practice, evaluation studies commonly only consider one indicator of program implementation. The present study investigates how two different aspects of program implementation - fidelity and participant responsiveness - jointly influence proximal

Hierarchical Motion Control for a Team of Humanoid Soccer Robots

Directory of Open Access Journals (Sweden)

Seung-Joon Yi

2016-02-01

Full Text Available Robot soccer has become an effective benchmarking problem for robotics research as it requires many aspects of robotics including perception, self localization, motion planning and distributed coordination to work in uncertain and adversarial environments. Especially with humanoid robots that lack inherent stability, a capable and robust motion controller is crucial for generating walking and kicking motions without losing balance. In this paper, we describe the details of a motion controller to control a team of humanoid soccer robots, which consists of a hierarchy of controllers with different time frames and abstraction levels. A low level controller governs the real time control of each joint angle, either using target joint angles or target endpoint transforms. A mid-level controller handles bipedal locomotion and balancing of the robot. A high level controller decides the long term behavior of the robot, and finally the team level controller coordinates the behavior of a group of robots by means of asynchronous communication between the robots. The suggested motion system has been successfully used by many humanoid robot teams at the RoboCup international robot soccer competitions, which has awarded us five successful championships in a row.

Design and Performance Analysis of a new Rotary Hydraulic Joint

Science.gov (United States)

Feng, Yong; Yang, Junhong; Shang, Jianzhong; Wang, Zhuo; Fang, Delei

2017-07-01

To improve the driving torque of the robots joint, a wobble plate hydraulic joint is proposed, and the structure and working principle are described. Then mathematical models of kinematics and dynamics was established. On the basis of this, dynamic simulation and characteristic analysis are carried out. Results show that the motion curve of the joint is continuous and the impact is small. Moreover the output torque of the joint characterized by simple structure and easy processing is large and can be rotated continuously.

38 CFR 4.59 - Painful motion.

Science.gov (United States)

2010-07-01

..., painful motion is an important factor of disability, the facial expression, wincing, etc., on pressure or... assist the identification. Sciatic neuritis is not uncommonly caused by arthritis of the spine. The... to healed injury, as entitled to at least the minimum compensable rating for the joint. Crepitation...

Knee joint motion and muscle activation patterns are altered during gait in individuals with moderate hip osteoarthritis compared to asymptomatic cohort.

Science.gov (United States)

Rutherford, Derek; Moreside, Janice; Wong, Ivan

2015-07-01

Knee replacements are common after hip replacement for end stage osteoarthritis. Whether abnormal knee mechanics exist in moderate hip osteoarthritis remains undetermined and has implications for understanding early osteoarthritis joint mechanics. The purpose of this study was to determine whether three-dimensional (3D) knee motion and muscle activation patterns in individuals with moderate hip osteoarthritis differ from an asymptomatic cohort and whether these features differ between contra- and ipsilateral knees. 3D motions and medial and lateral quadriceps and hamstring surface electromyography were recorded on 20 asymptomatic individuals and 20 individuals with moderate hip osteoarthritis during treadmill walking, using standardized collection and processing procedures. Principal component analysis was used to derive electromyographic amplitude and temporal waveform features. 3D stance-phase range of motion was calculated. A 2-factor repeated analysis of variance determined significant within-group leg and muscle differences. Student's t-tests identified between group differences, with Bonferroni corrections where applicable (α=0.05). Lower sagittal plane motion between early and mid/late stance (5°, P=0.004, effect size: 0.96) and greater mid-stance quadriceps activity was found in the osteoarthritis group (P=0.01). Compared to the ipsilateral knee, a borderline significant increase in mid-stance hamstring activity was found in the contra-lateral knee of the hip osteoarthritis group (P=0.018). Bilateral knee mechanics were altered, suggesting potentially increased loads and knee muscle fatigue. There was no indication that one knee is more susceptible to osteoarthritis than the other, thus clinicians should include bilateral knee analysis when treating patients with hip osteoarthritis. Copyright © 2015 Elsevier Ltd. All rights reserved.

The contribution of quasi-joint stiffness of the ankle joint to gait in patients with hemiparesis.

Science.gov (United States)

Sekiguchi, Yusuke; Muraki, Takayuki; Kuramatsu, Yuko; Furusawa, Yoshihito; Izumi, Shin-Ichi

2012-06-01

The role of ankle joint stiffness during gait in patients with hemiparesis has not been clarified. The purpose of this study was to determine the contribution of quasi-joint stiffness of the ankle joint to spatiotemporal and kinetic parameters regarding gait in patients with hemiparesis due to brain tumor or stroke and healthy individuals. Spatiotemporal and kinetic parameters regarding gait in twelve patients with hemiparesis due to brain tumor or stroke and nine healthy individuals were measured with a 3-dimensional motion analysis system. Quasi-joint stiffness was calculated from the slope of the linear regression of the moment-angle curve of the ankle joint during the second rocker. There was no significant difference in quasi-joint stiffness among both sides of patients and the right side of controls. Quasi-joint stiffness on the paretic side of patients with hemiparesis positively correlated with maximal ankle power (r=0.73, Phemiparesis. In contrast, healthy individuals might decrease quasi-joint stiffness to avoid deceleration of forward tilt of the tibia. Our findings might be useful for selecting treatment for increased ankle stiffness due to contracture and spasticity in patients with hemiparesis. Copyright © 2011 Elsevier Ltd. All rights reserved.

Suggested MR staging classification of early rheumatoid arthritis at the metacarpophalangeal and proximal interphalangeal joints

International Nuclear Information System (INIS)

Scheck, R.J.; Hoischen, S.H.; Willemsen, U.F.; Pfluger, T.; Kueffer, G.; Krueger, K.; Schattenkirchner, M.; Hahn, K.

1997-01-01

Purpose: MRI can demonstrate pathology of joint disease in the early course of rheumatoid arthritis prior to destructions seen on conventional radiographs. In a prospective study, we tried to develop a systematical classification of joint pathology demonstrated by MRI, which would be essential for scoring the course of the disease. Patients and method: Metacarpophalangeal and interphalangeal joints of 48 patients suffering from early rheumatoid arthritis (mean disease duration: 6.4 months) were evaluated by MRI using a high-resolution transmitter-receiver coil. Examinations included 2 mm sliced T 2 -, T 1 - and gadolinium enhanced T 1 -SE sequences in coronal and axial orientation. In consideration of pathological findings on MRI and histopathogenetical pathways of destruction in rheumatoid arthritis a MR-score (0-5) was established. Results: This allowed to score each joint examined: Score 0 (normal) in 47.8%/49.5%, score 1 in 35.5%/50.5%, score 2 in 4.2%/0%, score 3 in 10.8%/0%, score 4 in 1.5%/0% of the metacarpophalangeal/interphalangeal joints, respectively. Conclusions: Using the MR-score a relative individual destruction number can be calculated, which may be used to follow up patients in the early course of rheumatoid arthritis (e.g. drug therapy studies). The presented MR scoring system has to be evaluated further in longitudinal studies and must be correlated to radiographical and clinical findings. (orig.) [de

Early arthrosis of the digital joints

International Nuclear Information System (INIS)

Fischer, E.

1984-01-01

Arthrosis of the digital joints begins predominantly on the volar joint surface and the volar-proximal margin of the head. Because of this localisation, and in order to obtain adequate contrast and definition, these early changes are best shown by means of low R.V. radiographs in three views. The early changes consist of the following local processes: intrachondral sclerosis, exomarginal and endomarginal subchondral sclerosis, discreet increase in the spongiosa; this leads to disrounding and hooklike form of the head; thickening or disappearance of the sub-marginal spongiosa and marginal defects. Artifacts produced by the projections or local bone variants must be recognised, as well as diffuse idiopathic skeletal hyperostosis. (orig.) [de

Early arthrosis of the digital joints

Energy Technology Data Exchange (ETDEWEB)

Fischer, E.

1984-05-01

Arthrosis of the digital joints begins predominantly on the volar joint surface and the volar-proximal margin of the head. Because of this localisation, and in order to obtain adequate contrast and definition, these early changes are best shown by means of low R.V. radiographs in three views. The early changes consist of the following local processes: intrachondral sclerosis, exomarginal and endomarginal subchondral sclerosis, discreet increase in the spongiosa; this leads to disrounding and hooklike form of the head; thickening or disappearance of the sub-marginal spongiosa and marginal defects. Artifacts produced by the projections or local bone variants must be recognised, as well as diffuse idiopathic skeletal hyperostosis. 21 figs.

Influence of Different Hip Joint Centre Locations on Hip and Knee Joint Kinetics and Kinematics During the Squat

Directory of Open Access Journals (Sweden)

Sinclair Jonathan

2014-12-01

Full Text Available Identification of the hip joint centre (HJC is important in the biomechanical examination of human movement. However, there is yet to be any published information regarding the influence of different HJC locations on hip and knee joint kinetics during functional tasks. This study aimed to examine the influence of four different HJC techniques on 3- D hip and knee joint kinetics/kinematics during the squat. Hip and knee joint kinetics/kinematics of the squat were obtained from fifteen male participants using an eight camera motion capture system. The 3-D kinetics/kinematics of the squat were quantified using four hip joint centre estimation techniques. Repeated measures ANOVAs were used to compare the discrete parameters as a function of each HJC location. The results show that significant differences in joint angles and moment parameters were evident at both the hip and knee joint in the coronal and transverse planes. These observations indicate that when calculating non-sagittal joint kinetics/kinematics during the squat, researchers should carefully consider their HJC method as it may significantly affect the interpretation of their data.

Why is joint range of motion limited in patients with cerebral palsy?

NARCIS (Netherlands)

de Bruin, M.; Smeulders, M. J. C.; Kreulen, M.

2013-01-01

Patients with spastic cerebral palsy of the upper limb typically present with various problems including an impaired range of motion that affects the positioning of the upper extremity. This impaired range of motion often develops into contractures that further limit functioning of the spastic hand

Pelvic belt effects on sacroiliac joint ligaments: a computational approach to understand therapeutic effects of pelvic belts.

Science.gov (United States)

Sichting, Freddy; Rossol, Jerome; Soisson, Odette; Klima, Stefan; Milani, Thomas; Hammer, Niels

2014-01-01

The sacroiliac joint is a widely described source of low back pain. Therapeutic approaches to relieve pain include the application of pelvic belts. However, the effects of pelvic belts on sacroiliac joint ligaments as potential pain generators are mostly unknown. The aim of our study was to analyze the influence of pelvic belts on ligament load by means of a computer model. Experimental computer study using a finite element method. A computer model of the human pelvis was created, comprising bones, ligaments, and cartilage. Detailed geometries, material properties of ligaments, and in-vivo pressure distribution patterns of a pelvic belt were implemented. The effects of pelvic belts on ligament strain were computed in the double-leg stance. Pelvic belts increase sacroiliac joint motion around the sagittal axis but decrease motion around the transverse axis. With pelvic belt application, most of the strained sacroiliac joint ligaments were relieved, especially the sacrospinous, sacrotuberous, and the interosseous sacroiliac ligaments. Sacroiliac joint motion and ligament strains were minute. These results agree with validation data from other studies. Assigning homogenous and linear material properties and excluding muscle forces are clear simplifications of the complex reality. Pelvic belts alter sacroiliac joint motion and provide partial relief of ligament strain that is subjectively marked, although minimal in absolute terms. These findings confirm theories that besides being mechanical stabilizers, the sacroiliac joint ligaments are likely involved in neuromuscular feedback mechanisms. The results from our computer model help with unraveling the therapeutic mechanisms of pelvic belts.

Recruitment of knee joint ligaments

NARCIS (Netherlands)

Blankevoort, L.; Huiskes, H.W.J.; Lange, de A.

1991-01-01

On the basis of earlier reported data on the in vitro kinematics of passive knee-joint motions of four knee specimens, the length changes of ligament fiber bundles were determined by using the points of insertion on the tibia and femur. The kinematic data and the insertions of the ligaments were

Autonomous Quality Control of Joint Orientation Measured with Inertial Sensors

Directory of Open Access Journals (Sweden)

Karina Lebel

2016-07-01

Full Text Available Clinical mobility assessment is traditionally performed in laboratories using complex and expensive equipment. The low accessibility to such equipment, combined with the emerging trend to assess mobility in a free-living environment, creates a need for body-worn sensors (e.g., inertial measurement units—IMUs that are capable of measuring the complexity in motor performance using meaningful measurements, such as joint orientation. However, accuracy of joint orientation estimates using IMUs may be affected by environment, the joint tracked, type of motion performed and velocity. This study investigates a quality control (QC process to assess the quality of orientation data based on features extracted from the raw inertial sensors’ signals. Joint orientation (trunk, hip, knee, ankle of twenty participants was acquired by an optical motion capture system and IMUs during a variety of tasks (sit, sit-to-stand transition, walking, turning performed under varying conditions (speed, environment. An artificial neural network was used to classify good and bad sequences of joint orientation with a sensitivity and a specificity above 83%. This study confirms the possibility to perform QC on IMU joint orientation data based on raw signal features. This innovative QC approach may be of particular interest in a big data context, such as for remote-monitoring of patients’ mobility.

Coupling characteristics of rigid body motion and elastic deformation of a 3-PRR parallel manipulator with flexible links

International Nuclear Information System (INIS)

Zhang Xuping; Mills, James K.; Cleghorn, William L.

2009-01-01

Modeling of multibody dynamics with flexible links is a challenging task, which not only involves the effect of rigid body motion on elastic deformations, but also includes the influence of elastic deformations on rigid body motion. This paper presents coupling characteristics of rigid body motions and elastic motions of a 3-PRR parallel manipulator with three flexible intermediate links. The intermediate links are modeled as Euler-Bernoulli beams with pinned-pinned boundary conditions based on the assumed mode method (AMM). Using Lagrange multipliers, the fully coupled equations of motions of the flexible parallel manipulator are developed by incorporating the rigid body motions with elastic motions. The mutual dependence of elastic deformations and rigid body motions are investigated from the analysis of the derived equations of motion. Open-loop simulation without joint motion controls and closed-loop simulation with joint motion controls are performed to illustrate the effect of elastic motion on rigid body motions and the coupling effect amongst flexible links. These analyses and results provide valuable insight to the design and control of the parallel manipulator with flexible intermediate links

Uncemented three-dimensional-printed prosthetic reconstruction for massive bone defects of the proximal tibia.

Science.gov (United States)

Lu, Minxun; Li, Yongjiang; Luo, Yi; Zhang, Wenli; Zhou, Yong; Tu, Chongqi

2018-03-06

Currently, it is challenging to treat massive bone defects of proximal tibia. Although numerous methods are available for reconstruction with epiphysis preservation, limitations in knee function and complications are noted with these methods. Our paper describes our attempt to reconstruct a marked defect in the proximal tibia with an uncemented three-dimensional (3D)-printed prosthesis and to evaluate the prosthesis design and short-term outcomes. A 15-year-old boy with metaphyseal osteosarcoma of the tibia underwent intercalary allograft reconstruction following wide tumour resection with epiphysis preservation. However, chronic allograft rejection and/or infection occurred after the surgery and a sinus tract was formed. The rejection and/or infection process was successfully stopped by the removal of the graft and implantation of an antibiotic-loaded cement spacer; however, the limb function was poor. Because of the irregular shape of the defect and the excessively short length of the residual proximal tibia, we used the 3D printing technology to design and fabricate a personalised prosthesis to reconstruct the defect, with the preservation of the knee joint. At the last follow-up at 26 months, the patient had satisfactory limb function. The 3D-printed prosthesis may be a feasible option in the reconstruction of tibial metaphyseal defects with the preservation of the knee joint. Moreover, it can result in good postoperative function and low complication rates. However, a long-term follow-up is required to clarify its long-term outcomes.

Magnetic resonance imaging, radiography, and scintigraphy of the finger joints

DEFF Research Database (Denmark)

Klarlund, M; Ostergaard, M; Jensen, K E

2000-01-01

To evaluate synovial membrane hypertrophy, tenosynovitis, and erosion development of the 2nd to 5th metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints by magnetic resonance imaging in a group of patients with rheumatoid arthritis (RA) or suspected RA followed up for one year...

Inter-joint coordination between hips and trunk during downswings: Effects on the clubhead speed.

Science.gov (United States)

Choi, Ahnryul; Lee, In-Kwang; Choi, Mun-Taek; Mun, Joung Hwan

2016-10-01

Understanding of the inter-joint coordination between rotational movement of each hip and trunk in golf would provide basic knowledge regarding how the neuromuscular system organises the related joints to perform a successful swing motion. In this study, we evaluated the inter-joint coordination characteristics between rotational movement of the hips and trunk during golf downswings. Twenty-one right-handed male professional golfers were recruited for this study. Infrared cameras were installed to capture the swing motion. The axial rotation angle, angular velocity and inter-joint coordination were calculated by the Euler angle, numerical difference method and continuous relative phase, respectively. A more typical inter-joint coordination demonstrated in the leading hip/trunk than trailing hip/trunk. Three coordination characteristics of the leading hip/trunk reported a significant relationship with clubhead speed at impact (r joint coordination strategies have the great potential to use a biomechanical guideline to improve the golf swing performance of unskilled golfers.

Comparison of Joint Loading in Badminton Lunging between Professional and Amateur Badminton Players

OpenAIRE

Fu, Lin; Ren, Feng; Baker, Julien S.

2017-01-01

The knee and ankle are the two most injured joints associated with the sport of badminton. This study evaluates biomechanical factors between professional and amateur badminton players using an injury mechanism model. The aim of this study was to investigate the kinematic motion and kinetic loading differences of the right knee and ankle while performing a maximal right lunge. Amateur players exhibited greater ankle range of motion (p < 0.05, r = 0.89) and inversion joint moment (p < 0.05, r ...

Kinematics of Hooke universal joint robot wrists

Science.gov (United States)

Mckinney, William S., Jr.

1988-01-01

The singularity problem associated with wrist mechanisms commonly found on industrial manipulators can be alleviated by redesigning the wrist so that it functions as a three-axis gimbal system. This paper discussess the kinematics of gimbal robot wrists made of one and two Hooke universal joints. Derivations of the resolved rate motion control equations for the single and double Hooke universal joint wrists are presented using the three-axis gimbal system as a theoretical wrist model.

In Vivo Measurement of Glenohumeral Joint Contact Patterns

Directory of Open Access Journals (Sweden)

Bey MichaelJ

2010-01-01

Full Text Available The objectives of this study were to describe a technique for measuring in-vivo glenohumeral joint contact patterns during dynamic activities and to demonstrate application of this technique. The experimental technique calculated joint contact patterns by combining CT-based 3D bone models with joint motion data that were accurately measured from biplane x-ray images. Joint contact patterns were calculated for the repaired and contralateral shoulders of 20 patients who had undergone rotator cuff repair. Significant differences in joint contact patterns were detected due to abduction angle and shoulder condition (i.e., repaired versus contralateral. Abduction angle had a significant effect on the superior/inferior contact center position, with the average joint contact center of the repaired shoulder 12.1% higher on the glenoid than the contralateral shoulder. This technique provides clinically relevant information by calculating in-vivo joint contact patterns during dynamic conditions and overcomes many limitations associated with conventional techniques for quantifying joint mechanics.

Can orthoses and navicular drop affect foot motion patterns during running?

Science.gov (United States)

Eslami, Mansour; Ferber, Reed

2013-07-01

The purpose of this study was to examine the influence of semi-rigid foot orthoses on forefoot-rearfoot joint coupling patterns in individuals with different navicular drop measures during heel-toe running. Ten trials were collected from twenty-three male subjects who ran slowly shod at 170 steps per minute (2.23m/s) with a semi-rigid orthoses and without. Forefoot-rearfoot coupling motions were assessed using a vector coding technique during four intervals across the first 50% of stance. Subjects were divided into two groups based on navicular drop measures. A three way ANOVA was performed to examine the interaction and main effects of stance interval, orthoses condition and navicular drop (pForefoot-rearfoot coupling motion in the no-orthoses condition increased from heel-strike to foot-flat phase at a rate faster than the orthoses condition (p=0.02). Foot orthoses significantly decrease the forefoot-rearfoot joint coupling angle by reducing forefoot frontal plane motion relative to the rearfoot. Navicular drop measures did not influence joint coupling relationships between the forefoot and rearfoot during the first 50% of stance regardless of orthotic condition. Copyright © 2012 Sports Medicine Australia. All rights reserved.

Timing of electromyographic activity and ranges of motion during simple motor tasks of upper extremities

Directory of Open Access Journals (Sweden)

Syczewska Małgorzata

2017-10-01

Full Text Available Study aim: Improvement of the upper extremities’ performance is one of the key aims in the rehabilitation process. In order to achieve high effectiveness of this process the amount of functional improvement achieved by a patient during the therapy needs to be assessed. The aim of this study was to obtain electromyographic (EMG activity profiles of the upper extremity muscles during execution of simple tasks in healthy subjects. Additionally the ranges of wrist, elbow and shoulder joints were measured and reported during performed trials. The second aim was to determine whether the movement execution and ranges of move­ments and muscular activity depend on age. Material and methods: Twenty-eight healthy adults, age range 21 to 65 years old, participated in the study. Surface electrodes were placed bilaterally on 7 upper extremity muscles. To obtain information about the beginning and end of the movement task and ranges of upper extremity joints, 13 markers were placed on the elbows and wrists of both upper extremities. The move­ments of the segments were calculated (distal vs proximal in five simple functional tasks (each task involved only one joint, performed while sitting. Kinematic data were collected by the VICON 460 system, and electromyographic data with the Mo­tion Lab EMG system. Results: Charts of timing of EMG activity of the upper extremity muscles together with ranges of upper extremity joint motion were obtained. Conclusion: The results show that the number of muscles activated and the time (or percentage of the task during which they are active depend on the type of the task and age. These data can be used as a reference in evaluation of functional deficits of patients.

Mechanical Simulation of the Extension and Flexion of the Elbow Joint in Rehabilitation

Directory of Open Access Journals (Sweden)

Iman Vahdat

2013-01-01

Full Text Available Objective: The goal of the present study was to improve the extension and flexion of the elbow joint for rehabilitation purposes, in terms of energy dissipation and of injuries caused by stress imposed on connective tissue by exercise equipments during force transfer , by investigation of viscoelastic property variations during change in speed of motion. Materials & Methods: A sample of five men without any previous neuromuscular impairment of the elbow joint was chosen by the BMI factor. The passive continuous motion test (CPM was performed by the CYBEX isokinetic system in the extension and flexion movements of the elbow joint of the left hand, at 4 different speeds (15, 45, 75 and120 Deg/s during 5 consecutive cycles at the range of motion of about 0 to 130 degrees. The experimental data was exported to the MATLAB software for analysis. In order to determine viscoelastic property effects and biomechanical parameters, we used a passive viscoelastic mechanical model constructed by 3 elements for simulation, and also we used the curve fitting method to derive the elastic and viscose coefficients for the model.,. Results: Results of experiments showed that by increasing the speed of motion, the value of work done, hysteresis and elastic coefficient increased and the value of viscose coefficient decreased. Also, it appeared that by increasing the speed of motion, the effect of viscose resistance on the passive torque curves increased. In addition, there was significant correlation between the action of the mechanical model and the action of the concerned limbs, during the movement. Conclusion: It was concluded that in order to improve motion and to reduce imposed risks and injuries to joints and limbs, rehabilitation exercises better be performed at lower speeds and with rehabilitation equipments supported by viscoelastic resistant force.

The mirror game as a paradigm for studying the dynamics of two people improvising motion together

Science.gov (United States)

Noy, Lior; Dekel, Erez; Alon, Uri

2011-01-01

Joint improvisation is the creative action of two or more people without a script or designated leader. Examples include improvisational theater and music, and day-to-day activities such as conversations. In joint improvisation, novel action is created, emerging from the interaction between people. Although central to creative processes and social interaction, joint improvisation remains largely unexplored due to the lack of experimental paradigms. Here we introduce a paradigm based on a theater practice called the mirror game. We measured the hand motions of two people mirroring each other at high temporal and spatial resolution. We focused on expert actors and musicians skilled in joint improvisation. We found that players can jointly create novel complex motion without a designated leader, synchronized to less than 40 ms. In contrast, we found that designating one player as leader deteriorated performance: The follower showed 2–3 Hz oscillation around the leader's smooth trajectory, decreasing synchrony and reducing the range of velocities reached. A mathematical model suggests a mechanism for these observations based on mutual agreement on future motion in mirrored reactive–predictive controllers. This is a step toward understanding the human ability to create novelty by improvising together. PMID:22160696

[RESEARCH PROGRESS OF BIOMECHANICS OF PROXIMAL ROW CARPAL INSTABILITY].

Science.gov (United States)

Guo, Jinhai; Huang, Fuguo

2015-01-01

To review the research progress of the biomechanics of proximal row carpal instability (IPRC). The related literature concerning IPRC was extensively reviewed. The biomechanical mechanism of the surrounding soft tissue in maintaining the stability of the proximal row carpal (PRC) was analyzed, and the methods to repair or reconstruct the stability and function of the PRC were summarized from two aspects including basic biomechanics and clinical biomechanics. The muscles and ligaments of the PRC are critical to its stability. Most scholars have reached a consensus about biomechanical mechanism of the PRC, but there are still controversial conclusions on the biomechanics mechanism of the surrounding soft tissue to stability of distal radioulnar joint when the triangular fibrocartilage complex are damaged and the biomechanics mechanism of the scapholunate ligament. At present, there is no unified standard about the methods to repair or reconstruct the stability and function of the PRC. So, it is difficult for clinical practice. Some strides have been made in the basic biomechanical study on muscle and ligament and clinical biomechanical study on the methods to repair or reconstruct the stability and function of PRC, but it will be needed to further study the morphology of carpal articular surface and the adjacent articular surface, the pressure of distal carpals to proximal carpal and so on.

Range of motion and isometric strength of shoulder joints of team handball athletes during the playing season, Part II: changes after midseason.

Science.gov (United States)

Fieseler, Georg; Jungermann, Philipp; Koke, Alexander; Irlenbusch, Lars; Delank, Karl-Stefan; Schwesig, Rene

2015-03-01

Our objective was to investigate the influence of workload and consecutive changes on active range of motion and isometric strength of team handball athletes' throwing shoulders (TSs) because the available data are insufficient. In a longitudinal investigation, 31 professional male handball athletes underwent a clinical shoulder examination. Athletes were examined at the beginning (week 0), at the end (week 6) of the preseasonal training, and at the end of the half-season (week 22) on both shoulders to determine isometric rotational strength (hand held dynamometer) and active range of motion (goniometer). This analysis demonstrates the results subsequently from week 6 to week 22 and from week 0 to week 22. The glenohumeral internal rotation (IR) deficit (GIRD), external rotation (ER) gain, and ER at the TS increased significantly (P 0.10, d > 0.30) in the first sequence (week 6 to week 22) but not significantly from week 0 to week 22. The total range of motion remained stable, and IR changed but not significantly. There was no influence on IR, ER, and total range of motion at the non-TS. The isometric strength of the TS and non-TS IR did not change. The isometric strength in ER significantly increased bilaterally during the investigation period. Our data verify changes and influences, such as an increasing GIRD, at the overhead TS joint in accordance with the workload during team handball season. ER gain did improve after the half-season period but did not fully compensate the GIRD at the TS. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Biomechanical energy harvesting from human motion: theory, state of the art, design guidelines, and future directions.

Science.gov (United States)

Riemer, Raziel; Shapiro, Amir

2011-04-26

Biomechanical energy harvesting from human motion presents a promising clean alternative to electrical power supplied by batteries for portable electronic devices and for computerized and motorized prosthetics. We present the theory of energy harvesting from the human body and describe the amount of energy that can be harvested from body heat and from motions of various parts of the body during walking, such as heel strike; ankle, knee, hip, shoulder, and elbow joint motion; and center of mass vertical motion. We evaluated major motions performed during walking and identified the amount of work the body expends and the portion of recoverable energy. During walking, there are phases of the motion at the joints where muscles act as brakes and energy is lost to the surroundings. During those phases of motion, the required braking force or torque can be replaced by an electrical generator, allowing energy to be harvested at the cost of only minimal additional effort. The amount of energy that can be harvested was estimated experimentally and from literature data. Recommendations for future directions are made on the basis of our results in combination with a review of state-of-the-art biomechanical energy harvesting devices and energy conversion methods. For a device that uses center of mass motion, the maximum amount of energy that can be harvested is approximately 1 W per kilogram of device weight. For a person weighing 80 kg and walking at approximately 4 km/h, the power generation from the heel strike is approximately 2 W. For a joint-mounted device based on generative braking, the joints generating the most power are the knees (34 W) and the ankles (20 W). Our theoretical calculations align well with current device performance data. Our results suggest that the most energy can be harvested from the lower limb joints, but to do so efficiently, an innovative and light-weight mechanical design is needed. We also compared the option of carrying batteries to the

AMUC: Associated Motion capture User Categories.

Science.gov (United States)

Norman, Sally Jane; Lawson, Sian E M; Olivier, Patrick; Watson, Paul; Chan, Anita M-A; Dade-Robertson, Martyn; Dunphy, Paul; Green, Dave; Hiden, Hugo; Hook, Jonathan; Jackson, Daniel G

2009-07-13

The AMUC (Associated Motion capture User Categories) project consisted of building a prototype sketch retrieval client for exploring motion capture archives. High-dimensional datasets reflect the dynamic process of motion capture and comprise high-rate sampled data of a performer's joint angles; in response to multiple query criteria, these data can potentially yield different kinds of information. The AMUC prototype harnesses graphic input via an electronic tablet as a query mechanism, time and position signals obtained from the sketch being mapped to the properties of data streams stored in the motion capture repository. As well as proposing a pragmatic solution for exploring motion capture datasets, the project demonstrates the conceptual value of iterative prototyping in innovative interdisciplinary design. The AMUC team was composed of live performance practitioners and theorists conversant with a variety of movement techniques, bioengineers who recorded and processed motion data for integration into the retrieval tool, and computer scientists who designed and implemented the retrieval system and server architecture, scoped for Grid-based applications. Creative input on information system design and navigation, and digital image processing, underpinned implementation of the prototype, which has undergone preliminary trials with diverse users, allowing identification of rich potential development areas.

Development of a new modeling technique of 3D S-wave velocity structure for strong ground motion evaluation - Integration of various geophysical and geological data using joint inversion

International Nuclear Information System (INIS)

Sugimoto, Yoshihiro

2014-01-01

A restricted stripe-like zone suffered major damage due to the 1995 Hyogo-ken Nanbu earthquake, and ground motion of the south side of the Kashiwazaki NPP site was much greater than that of the north side in the 2007 Niigata-ken Chuetsu-oki earthquake. One reason for these phenomena is thought to be the focusing effect due to irregularly shaped sedimentary basins (e.g., basin-edge structure, fold structure, etc.) This indicates that precise evaluation of S-wave velocity structure is important. A calculation program that was developed to make S-wave velocity models using the joint inversion method was presented. This program unifies various geophysical and geological data and can make a complex structure model for evaluating strong ground motion with high precision. (author)

Motion Segments Decomposition of RGB-D Sequences for Human Behavior Understanding

OpenAIRE

Devanne , Maxime; Berretti , Stefano; Pala , Pietro; Wannous , Hazem; Daoudi , Mohamed; Bimbo , Alberto ,

2017-01-01

International audience; In this paper, we propose a framework for analyzing and understanding human behavior from depth videos. The proposed solution first employs shape analysis of the human pose across time to decompose the full motion into short temporal segments representing elementary motions. Then, each segment is characterized by human motion and depth appearance around hand joints to describe the change in pose of the body and the interaction with objects. Finally , the sequence of te...

Efficacy of Low Level Laser Therapy After Hand Flexor Tendon Repair

Science.gov (United States)

Ayad, K. E.; El Gohary, H. M.; Abd Elrahman, M.; Abd El Mejeed, S. F.; Bekheet, A. B.

2009-09-01

Flexor tendon injury is a common problem requiring suturing repair followed by early postoperative mobilization. Muscle atrophy, joint stiffness, osteoarthritis, infection, skin necrosis, ulceration of joint cartilage and tendocutaneous adhesion are familiar complications produced by prolonged immobilization of surgically repaired tendon ruptures. The purpose of this study was to clarify the importance of low level laser therapy after hand flexor tendon repair in zone II. Thirty patients aging between 20 and 40 years were divided into two groups. Patients in group A (n = 15) received a conventional therapeutic exercise program while patients in group B (n = 15) received low level laser therapy combined with the same therapeutic exercise program. The results showed a statistically significant increase in total active motion of the proximal and distal interphalangeal joints as well as maximum hand grip strength at three weeks and three months postoperative, but improvement was more significant in group B. It was concluded that the combination of low level laser therapy and early therapeutic exercises was more effective than therapeutic exercises alone in improving total active motion of proximal and distal interphalangeal joints and hand grip strength after hand flexor tendon repair.

Effects of prophylactic knee bracing on knee joint kinetics and kinematics during netball specific movements.

Science.gov (United States)

Sinclair, Jonathan K; Vincent, Hayley; Richards, Jim D

2017-01-01

To investigate the effects of a prophylactic knee brace on knee joint kinetics and kinematics during netball specific movements. Repeated measures. Laboratory. Twenty university first team level female netball players. Participants performed three movements, run, cut and vertical jump under two conditions (brace and no-brace). 3-D knee joint kinetics and kinematics were measured using an eight-camera motion analysis system. Knee joint kinetics and kinematics were examined using 2 × 3 repeated measures ANOVA whilst the subjective ratings of comfort and stability were investigated using chi-squared tests. The results showed no differences (p > 0.05) in knee joint kinetics. However the internal/external rotation range of motion was significantly (p < 0.05) reduced when wearing the brace in all movements. The subjective ratings of stability revealed that netballers felt that the knee brace improved knee stability in all movements. Further study is required to determine whether reductions in transverse plane knee range of motion serve to attenuate the risk from injury in netballers. Copyright © 2016 Elsevier Ltd. All rights reserved.

Synovial Osteochondromatosis at the Carpometacarpal Joint of the Thumb

Directory of Open Access Journals (Sweden)

Satoru Yonekura

2017-01-01

Full Text Available Synovial osteochondromatosis (SOC is a benign tumor characterized by synovial connective tissue metaplasia. SOC commonly affects major joints including the knee followed by the hip, elbow, and wrist. SOC cases in the hand are not reported as often as SOC of major joints. Particularly SOC of the carpometacarpal joint of the thumb is rare. We report on a 57-year-old female with primary SOC of the carpometacarpal joint of her left thumb. Surgical excision was performed and the patient had no symptoms with full range of motion of her left thumb. At 3 years of follow-up, there was no recurrence.

Biological inspiration used for robots motion synthesis.

Science.gov (United States)

Zielińska, Teresa

2009-01-01

This work presents a biologically inspired method of gait generation. Bipedal gait pattern (for hip and knee joints) was taken into account giving the reference trajectories in a learning task. The four coupled oscillators were taught to generate the outputs similar to those in a human gait. After applying the correction functions the obtained generation method was validated using ZMP criterion. The formula suitable for real-time motion generation taking into account the positioning errors was also formulated. The small real robot prototype was tested to be able walk successfully following the elaborated motion pattern.

Relationship of medial gastrocnemius relative fascicle excursion and ankle joint power and work performance during gait in typically developing children: A cross-sectional study.

Science.gov (United States)

Martín Lorenzo, Teresa; Albi Rodríguez, Gustavo; Rocon, Eduardo; Martínez Caballero, Ignacio; Lerma Lara, Sergio

2017-07-01

Muscle fascicles lengthen in response to chronic passive stretch through in-series sarcomere addition in order to maintain an optimum sarcomere length. In turn, the muscles' force generating capacity, maximum excursion, and contraction velocity is enhanced. Thus, longer fascicles suggest a greater capacity to develop joint power and work. However, static fascicle length measurements may not be taking sarcomere length differences into account. Thus, we considered relative fascicle excursions through passive ankle dorsiflexion may better correlate with the capacity to generate joint power and work than fascicle length. Therefore, the aim of the present study was to determine if medial gastrocnemius relative fascicle excursions correlate with ankle joint power and work generation during gait in typically developing children. A sample of typically developing children (n = 10) were recruited for this study and data analysis was carried out on 20 legs. Medial gastrocnemius relative fascicle excursion from resting joint angle to maximum dorsiflexion was estimated from trigonometric relations of medial gastrocnemius pennation angle and thickness obtained from B-mode real-time ultrasonography. Furthermore, a three-dimensional motion capture system was used to obtain ankle joint work and power during the stance phase of gait. Significant correlations were found between relative fascicle excursion and peak power absorption (-) r(14) = -0.61, P = .012 accounting for 31% variability, positive work r(18) = 0.56, P = .021 accounting for 31% variability, and late stance positive work r(15) = 0.51, P = .037 accounting for 26% variability. The large unexplained variance may be attributed to mechanics of neighboring structures (e.g., soleus or Achilles tendon mechanics) and proximal joint kinetics which may also contribute to ankle joint power and work performance, and were not taken into account. Further studies are encouraged to provide greater insight

Detailed examination of the lower cervical spine facet joints in a road traffic crash fatality - a case study

DEFF Research Database (Denmark)

Uhrenholt, Lars; Nielsen, Edith; Vesterby, Annie

2005-01-01

The lower cervical spine facet joints of a road traffic crash fatality were examined using diagnostic imaging and histological techniques. No injuries to the cervical spine facet joints could be identified with diagnostic imaging including conventional radiology, CT and MRI. Examination of stained...... histological sections visualised the morphology and integrity of the facet joints in detail. Occult injuries to and in close proximity of the cervical spine facet joints were identified only on histological examination....

The Effect of 2 Forms of Talocrural Joint Traction on Dorsiflexion Range of Motion and Postural Control in Those With Chronic Ankle Instability.

Science.gov (United States)

Powden, Cameron J; Hogan, Kathleen K; Wikstrom, Erik A; Hoch, Matthew C

2017-05-01

Talocrural joint mobilizations are commonly used to address deficits associated with chronic ankle instability (CAI). Examine the immediate effects of talocrural joint traction in those with CAI. Blinded, crossover. Laboratory. Twenty adults (14 females; age = 23.80 ± 4.02 y; height = 169.55 ± 12.38 cm; weight = 78.34 ± 16.32 kg) with self-reported CAI participated. Inclusion criteria consisted of a history of ≥1 ankle sprain, ≥2 episodes of giving way in the previous 3 mo, answering "yes" to ≥4 questions on the Ankle Instability Instrument, and ≤24 on the Cumberland Ankle Instability Tool. Subjects participated in 3 sessions in which they received a single treatment session of sustained traction (ST), oscillatory traction (OT), or a sham condition in a randomized order. Interventions consisted of four 30-s sets of traction with 1 min of rest between sets. During ST and OT, the talus was distracted distally from the ankle mortise to the end-range of accessory motion. ST consisted of continuous distraction and OT involved 1-s oscillations between the mid and end-range of accessory motion. The sham condition consisted of physical contact without force application. Preintervention and postintervention measurements of weight-bearing dorsiflexion, dynamic balance, and static single-limb balance were collected. The independent variable was treatment (ST, OT, sham). The dependent variables included pre-to-posttreatment change scores for the WBLT (cm), normalized SEBTAR (%), and time-to-boundary (TTB) variables(s). Separate 1-way ANOVAs examined differences between treatments for each dependent variable. Alpha was set a priori at P manual therapies.

SISMA (Site of Italian Strong Motion Accelerograms): a Web-Database of Ground Motion Recordings for Engineering Applications

International Nuclear Information System (INIS)

Scasserra, Giuseppe; Lanzo, Giuseppe; D'Elia, Beniamino; Stewart, Jonathan P.

2008-01-01

The paper describes a new website called SISMA, i.e. Site of Italian Strong Motion Accelerograms, which is an Internet portal intended to provide natural records for use in engineering applications for dynamic analyses of structural and geotechnical systems. SISMA contains 247 three-component corrected motions recorded at 101 stations from 89 earthquakes that occurred in Italy in the period 1972-2002. The database of strong motion accelerograms was developed in the framework of a joint project between Sapienza University of Rome and University of California at Los Angeles (USA) and is described elsewhere. Acceleration histories and pseudo-acceleration response spectra (5% damping) are available for download from the website. Recordings can be located using simple search parameters related to seismic source and the recording station (e.g., magnitude, V s30 , etc) as well as ground motion characteristics (e.g. peak ground acceleration, peak ground velocity, peak ground displacement, Arias intensity, etc.)

Correction of Hallux Valgus Interphalangeus With an Osteotomy of the Distal End of the Proximal Phalanx (Distal Akin Osteotomy).

Science.gov (United States)

Vander Griend, Robert

2017-02-01

Operative correction of a symptomatic hallux valgus interphalangeus (HVI) deformity is often achieved with an osteotomy at the proximal end of the proximal phalanx (Akin osteotomy). However, the apex of the typical HVI deformity (center of rotation angle) is at the interphalangeal joint of the hallux. This study was done to evaluate the results of performing a medial closing wedge osteotomy at the distal end of the proximal phalanx. Thirty-three patients (33 feet) underwent an osteotomy at the distal end of the proximal phalanx for correction of HVI. All of the patients had other forefoot deformities which were corrected at the same time. Eight of these were revision procedures of prior forefoot operations. The length of follow-up was determined by the associated procedures with a minimum follow-up of 4 months. The preoperative hallux valgus interphalangeus angle averaged 16 degrees of valgus (range 7-32 degrees) and was corrected to an average of 2 degrees of valgus (range 5 degrees valgus to 5 degrees varus). All of the patients were satisfied with the postoperative appearance and function of the first toe. Because of simultaneous correction of numerous other forefoot problems, it was not possible to specifically isolate or evaluate the effects and benefits of this osteotomy using outcomes measures. There was one intraoperative complication resulting in a fracture extending into the adjacent IP joint. Correction of an HVI deformity can be achieved with an osteotomy at the distal end of the proximal phalanx. This was a safe technique with few complications and with good results in terms of both correction and patient satisfaction. Level IV, retrospective case series.

Effects of joint mobilization on chronic ankle instability: a randomized controlled trial.

Science.gov (United States)

Cruz-Díaz, David; Lomas Vega, Rafael; Osuna-Pérez, Maria Catalina; Hita-Contreras, Fidel; Martínez-Amat, Antonio

2015-01-01

To evaluate the effects of joint mobilization, in which movement is applied to the ankle's dorsiflexion range of motion, on dynamic postural control and on the self-reported instability of patients with chronic ankle instability (CAI). A double-blind, placebo-controlled, randomized trial with repeated measures and a follow-up period. Ninety patients with a history of recurrent ankle sprain, self-reported instability, and a limited dorsiflexion range of motion, were randomly assigned to either the intervention group (Joint Mobilizations, 3 weeks, two sessions per week) the placebo group (Sham Mobilizations, same duration as joint mobilization) or the control group, with a 6 months follow-up. Dorsiflexion Range of Motion (DFROM), Star Excursion Balance Test (SEBT) and CAI Tool (CAIT) were outcome measures. A separate 3 × 4 mixed model analysis of variance was performed to examine the effect of treatment conditions and time, and intention-to-treat (ITT) analysis was applied to evaluate the effect of the independent variable. The application of joint mobilization resulted in better scores of DFROM, CAIT, and SEBTs in the intervention group when compared with the placebo or the control groups (p ankle DFROM, postural control, and self-reported instability. These results suggest that joint mobilization could be applied to patients with recurrent ankle sprain to help restore their functional stability. Implications for Rehabilitation Functional instability is a very common sequela in patients with CAI, resulting in reduced quality of living due to the limitations it imposes on daily life activities. The mobilization with movement technique presented by Mulligan, and based on the joint mobilization accompanied by active movement, appears as a valuable tool to be employed by physical therapists to restore ankle function after a recurrent ankle sprain history. ROM restriction, subjective feeling of instability and dynamic postural control are benefiting from the joint

Control of compliant anthropomimetic robot joint

Directory of Open Access Journals (Sweden)

Svetozarević Bratislav

2011-01-01

Full Text Available In this paper we propose a control strategy for a robot joint which fully mimics the typical human joint structure. The joint drive is based on two actuators (dc motors, agonist and antagonist, acting through compliant tendons and forming a nonlinear multi-input multi-output (MIMO system. At any time, we consider one actuator, the puller, as being responsible for motion control, while the role of the other is to keep its tendon force at some appropriate low level. This human-like and energetically efficient approach requires the control of 'switching', or exchanging roles between actuators. Moreover, an algorithm based on adaptive force reference is used to solve a problem of slacken tendons during the switching and to increase the energy efficiency. This approach was developed and evaluated on increasingly complex robot joint configurations, starting with simple and noncompliant system, and finishing with nonlinear and compliant system.

Acromioclavicular joint separation

Directory of Open Access Journals (Sweden)

Devan Pandya, BS

2018-04-01

Full Text Available History of present illness: A 30-year-old male was brought in by ambulance to the emergency department as a trauma activation after a motorcycle accident. The patient was the helmeted rider of a motorcycle traveling at an unknown speed when he lost control and was thrown off his vehicle. He denied loss of consciousness, nausea, or vomiting. The patient’s vital signs were stable and his only complaint was pain around his left shoulder. On exam, the patient had a prominent left clavicle without skin compromise. He had adequate range of motion in the left shoulder with moderate pain, and his left upper extremity was neurovascularly intact. Significant findings: Plain films of the left shoulder showed elevation of the left clavicle above the acromion. There was an increase in the acromioclavicular (AC and coracoclavicular (CC distances (increased joint distances marked with red and blue arrows, respectively. A normal AC joint measures 1-3 mm whereas a normal CC distance measures 11-13 mm.1 The injury was classified as a Rockwood type III AC joint separation. Discussion: The AC joint is a synovial joint between an oval facet on the acromion and a similar facet on the distal end of the clavicle. Horizontal stability is provided by the AC joint while axial stability is provided by the CC joint.2,3 AC joint injuries account for about 9%-12% of shoulder girdle injuries, and the most common mechanism is direct trauma.4,5 Initial evaluation with imaging includes plain films with three views: the anterior-posterior (AP view with the shoulder in internal and external rotation as well as an axillary, or scapula-Y view (sensitivity 40%, specificity 90% for all films.6,7 AC joint injuries are classified by the Rockwood system.8 Type I involves a sprain or incomplete tear of the AC ligaments with an intact CC ligament. The AC joint appears normal on X-ray, but can become widened with stress, achieved by having the patient hold a 10-15 pound weight from each

Extraction and Analysis of Respiratory Motion Using Wearable Inertial Sensor System during Trunk Motion

Directory of Open Access Journals (Sweden)

Apoorva Gaidhani

2017-12-01

Full Text Available Respiratory activity is an essential vital sign of life that can indicate changes in typical breathing patterns and irregular body functions such as asthma and panic attacks. Many times, there is a need to monitor breathing activity while performing day-to-day functions such as standing, bending, trunk stretching or during yoga exercises. A single IMU (inertial measurement unit can be used in measuring respiratory motion; however, breathing motion data may be influenced by a body trunk movement that occurs while recording respiratory activity. This research employs a pair of wireless, wearable IMU sensors custom-made by the Department of Electrical Engineering at San Diego State University. After appropriate sensor placement for data collection, this research applies principles of robotics, using the Denavit-Hartenberg convention, to extract relative angular motion between the two sensors. One of the obtained relative joint angles in the “Sagittal” plane predominantly yields respiratory activity. An improvised version of the proposed method and wearable, wireless sensors can be suitable to extract respiratory information while performing sports or exercises, as they do not restrict body motion or the choice of location to gather data.

Magnetic resonance imaging-based morphological and alignment assessment of the patellofemoral joint and its relationship to proximal patellar tendinopathy

Energy Technology Data Exchange (ETDEWEB)

Crema, Michel D. [Hospital do Coracao (HCor) and Teleimagem, Department of Radiology, Sao Paulo, SP (Brazil); University Paris VI, Department of Radiology, Hopital Saint-Antoine, Paris (France); Boston University School of Medicine, Department of Radiology, Quantitative Imaging Center, Boston, MA (United States); Cortinas, Larissa G.; Lima, Giovanni B.P.; Skaf, Abdalla Y. [Hospital do Coracao (HCor) and Teleimagem, Department of Radiology, Sao Paulo, SP (Brazil); Abdalla, Rene Jorge; McNeill Ingham, Sheila Jean [Federal University of Sao Paulo, Department of Orthopaedic Surgery, School of Medicine, Sao Paulo (Brazil); Hospital do Coracao (HCor), Knee Institute, Sao Paulo, SP (Brazil)

2018-03-15

To assess the differences in morphology and alignment of the knee between patients with proximal patellar tendinopathy (PPT) and a control group, using MRI and focusing on the patellofemoral joint. We retrospectively included 35 patients with clinically diagnosed and unequivocal findings of PPT on knee MRI, the case group. For the control group, we included 70 patients who underwent knee MRI for other reasons, with no clinical or MRI evidence of PPT. Patients and controls were matched for age and gender, with all subjects reporting frequent physical activity. MRIs were evaluated by two musculoskeletal radiologists, who assessed parameters of patellar morphology, trochlear morphology, patellofemoral alignment, and tibiofemoral alignment. The differences in parameters between cases and controls were assessed using Student's t test. Logistic regression was applied to assess the associations between the MRI parameters and the presence of PPT. The patellar height Insall-Salvati ratio was different between cases and controls (1.37 ± 0.21 vs. 1.24 ± 0.19; p = 0.003). The subchondral Wiberg angle was higher in cases than controls (136.8 ± 7.4 vs. 131.7 ± 8.8; p = 0.004). After applying logistic regression, significant associations with PPT were found [odds ratios (95% CI)] for patellar morphology [1.1 (1.0, 1.2)] and patellar height [1.3 (1.0, 1.7)]. Patellar height and the subchondral patellar Wiberg angle were greater in patients with PPT and significantly associated with PPT. (orig.)

Magnetic resonance imaging-based morphological and alignment assessment of the patellofemoral joint and its relationship to proximal patellar tendinopathy

International Nuclear Information System (INIS)

Crema, Michel D.; Cortinas, Larissa G.; Lima, Giovanni B.P.; Skaf, Abdalla Y.; Abdalla, Rene Jorge; McNeill Ingham, Sheila Jean

2018-01-01

To assess the differences in morphology and alignment of the knee between patients with proximal patellar tendinopathy (PPT) and a control group, using MRI and focusing on the patellofemoral joint. We retrospectively included 35 patients with clinically diagnosed and unequivocal findings of PPT on knee MRI, the case group. For the control group, we included 70 patients who underwent knee MRI for other reasons, with no clinical or MRI evidence of PPT. Patients and controls were matched for age and gender, with all subjects reporting frequent physical activity. MRIs were evaluated by two musculoskeletal radiologists, who assessed parameters of patellar morphology, trochlear morphology, patellofemoral alignment, and tibiofemoral alignment. The differences in parameters between cases and controls were assessed using Student's t test. Logistic regression was applied to assess the associations between the MRI parameters and the presence of PPT. The patellar height Insall-Salvati ratio was different between cases and controls (1.37 ± 0.21 vs. 1.24 ± 0.19; p = 0.003). The subchondral Wiberg angle was higher in cases than controls (136.8 ± 7.4 vs. 131.7 ± 8.8; p = 0.004). After applying logistic regression, significant associations with PPT were found [odds ratios (95% CI)] for patellar morphology [1.1 (1.0, 1.2)] and patellar height [1.3 (1.0, 1.7)]. Patellar height and the subchondral patellar Wiberg angle were greater in patients with PPT and significantly associated with PPT. (orig.)

Effects of five hindfoot arthrodeses on foot and ankle motion: Measurements in cadaver specimens

Science.gov (United States)

Zhang, Kun; Chen, Yanxi; Qiang, Minfei; Hao, Yini

2016-01-01

Single, double, and triple hindfoot arthrodeses are used to correct hindfoot deformities and relieve chronic pain. However, joint fusion may lead to dysfunction in adjacent articular surfaces. We compared range of motion in adjacent joints before and after arthrodesis to determine the effects of each procedure on joint motion. The theory of moment of couple, bending moment and balanced loading was applied to each of 16 fresh cadaver feet to induce dorsiflexion, plantarflexion, internal rotation, external rotation, inversion, and eversion. Range of motion was measured with a 3-axis coordinate measuring machine in a control foot and in feet after subtalar, talonavicular, calcaneocuboid, double, or triple arthrodesis. All arthrodeses restricted mainly internal-external rotation and inversion-eversion. The restriction in a double arthrodesis was more than that in a single arthrodesis, but that in a calcaneocuboid arthrodesis was relatively low. After triple arthrodeses, the restriction on dorsiflexion and plantarflexion movements was substantial, and internal-external rotation and inversion-eversion were almost lost. Considering that different arthrodesis procedures cause complex, three-dimensional hindfoot motion reductions, we recommend talonavicular or calcaneocuboid arthrodesis for patients with well-preserved functions of plantarflexion/dorsiflexion before operation, subtalar or calcaneocuboid arthrodesis for patients with well-preserved abduction/adduction, and talonavicular arthrodesis for patients with well-preserved eversion/inversion. PMID:27752084

MR imaging of the normal sacroiliac joint with correlation to histology

Energy Technology Data Exchange (ETDEWEB)

Puhakka, K.B.; Jurik, A.G.; Egund, N. [Department of Radiology, Aarhus University Hospital, Aarhus Kommunehospital, 8000, Aarhus (Denmark); Melsen, F. [Institute of Pathology, Aarhus University Hospital, Aarhus Amtssygehus, Aarhus (Denmark); Boel, L.W.; Vesterby, A. [Institute of Forensic Medicine, University of Aarhus, Aarhus (Denmark)

2004-01-01

The microscopic study of the various components of joints provide a proper basis for understanding the nature of pathologic lesions to which they are subject and their imaging appearances. This study was designed to correlate MR imaging with a systematic histological study of the normal sacroiliac joint (SIJ), which to our knowledge is not available in the literature. Five male cadavers, aged 20 to 45 years, and seven male and seven female volunteers, aged 23 to 44 years, were investigated with oblique transaxial and coronal MR imaging of the SIJs. A variety of sequences including pre- and post-contrast T1 fat-saturated studies in the volunteers were used. Cryosectioning was performed in six SIJs of the five cadavers and compared with the MR images for the microscopic joint anatomy and assessed for the presence of abnormalities resembling those associated with sacroiliitis. Throughout the SIJ, the hyaline cartilage of the sacral bone and the proximal third of the hyaline iliac cartilage was strongly attached to the surrounding stabilizing ligaments, forming wide margins of fibrocartilage. In the distal one-third of the joint only, the margins of the iliac joint facet resemble that of a synovial joint, which include an inner capsule with synovial cells. The MR anatomy of the ventral and dorsal aspects of the SIJ was only adequately visualized at oblique transaxial MR imaging. No contrast enhancement occurred in the synovial tissue or in the cartilaginous joint space. The dorsal transition between the proximal 2/3 and distal 1/3 of the cartilaginous joint was at microscopy rich in anatomical and histological variants, including osseous clefts, cartilage and subchondral defects, and vascular connective tissue in the bone marrow. These were all recognized at oblique transaxial MR imaging and in coronal MR sectioning may resemble abnormalities. Otherwise, no erosions, bone marrow abnormalities, bone sclerosis or abnormal contrast enhancement occurred in the normal

A Method for and Issues Associated with the Determination of Space Suit Joint Requirements

Science.gov (United States)

Matty, Jennifer E.; Aitchison, Lindsay

2009-01-01

In the design of a new space suit it is necessary to have requirements that define what mobility space suit joints should be capable of achieving in both a system and at the component level. NASA elected to divide mobility into its constituent parts-range of motion (ROM) and torque- in an effort to develop clean design requirements that limit subject performance bias and are easily verified. Unfortunately, the measurement of mobility can be difficult to obtain. Current technologies, such as the Vicon motion capture system, allow for the relatively easy benchmarking of range of motion (ROM) for a wide array of space suit systems. The ROM evaluations require subjects in the suit to accurately evaluate the ranges humans can achieve in the suit. However, when it comes to torque, there are significant challenges for both benchmarking current performance and writing requirements for future suits. This is reflected in the fact that torque definitions have been applied to very few types of space suits and with limited success in defining all the joints accurately. This paper discussed the advantages and disadvantages to historical joint torque evaluation methods, describes more recent efforts directed at benchmarking joint torques of prototype space suits, and provides an outline for how NASA intends to address joint torque in design requirements for the Constellation Space Suit System (CSSS).

The morphology of synovial grooves (Fossae synoviales) in joints of cattle of different age groups

DEFF Research Database (Denmark)

Wegener, K. M.; Heje, N. I.; Aarestrup, Frank Møller

1993-01-01

The joint cartilage of the head of the radius, the metacarpal bone, the tibial cochlea, the proximal trochlea of the talus and the metatarsal bone of 26 cattle in the age groups fetuses, 0 days, 2-5 weeks, 2-5 months, 7-13 months, 2-3.5 years, and 5-7 years were examined macroscopically...... animals aged from 3 weeks to 13 months dyschondroplastic (osteochondrotic) lesions were observed in the joint cartilage both inside and outside the groove areas on one or more joint surfaces....

Conjunctions between motion and disparity are encoded with the same spatial resolution as disparity alone.

Science.gov (United States)

Allenmark, Fredrik; Read, Jenny C A

2012-10-10

Neurons in cortical area MT respond well to transparent streaming motion in distinct depth planes, such as caused by observer self-motion, but do not contain subregions excited by opposite directions of motion. We therefore predicted that spatial resolution for transparent motion/disparity conjunctions would be limited by the size of MT receptive fields, just as spatial resolution for disparity is limited by the much smaller receptive fields found in primary visual cortex, V1. We measured this using a novel "joint motion/disparity grating," on which human observers detected motion/disparity conjunctions in transparent random-dot patterns containing dots streaming in opposite directions on two depth planes. Surprisingly, observers showed the same spatial resolution for these as for pure disparity gratings. We estimate the limiting receptive field diameter at 11 arcmin, similar to V1 and much smaller than MT. Higher internal noise for detecting joint motion/disparity produces a slightly lower high-frequency cutoff of 2.5 cycles per degree (cpd) versus 3.3 cpd for disparity. This suggests that information on motion/disparity conjunctions is available in the population activity of V1 and that this information can be decoded for perception even when it is invisible to neurons in MT.

[Short-term effectiveness of Swanson artificial joint replacement in treating posttraumatic metacarpophalangeal joint stiffness].

Science.gov (United States)

Lu, Hui; Shen, Xiangqian; Xu, Jihua; Huang, Xin; Ye, Po; Wu, Shoucheng

2011-11-01

To investigate the short-term effectiveness of Swanson artificial joint replacement in treating post-traumatic metacarpophalangeal joint stiffness. Between August 2007 and May 2010, 11 cases (13 fingers) of metacarpophalangeal joint stiffness with soft tissue defects underwent Swanson artificial joint replacement. There were 7 males (9 fingers) and 4 females (4 fingers), aged 43 to 65 years with an average of 49 years. The involved fingers included 4 thumbs, 4 index fingers, 3 middle fingers, and 2 ring fingers. The types of injury included open and crush injury in 8 fingers, fracture of the metacarpophalangeal joint in 3 fingers, metacarpophalangeal joint severing in 2 fingers. The time from joint stiffness to hospitalization was 12 to 48 weeks (mean, 24 weeks). The joint activity was (136.82 +/- 28.96) degrees. According to total active motion (TAM) assessment, included good in 1 finger, fair in 6 fingers, and poor in 6 fingers before operation. The activities of daily living were assessed by Sollerman score, which was 45.64 +/- 11.04. The X-ray films and CT scan showed traumatic arthritis of the metacarpophalangeal joint. The incision healed by first intention. All patients were followed up 12 to 34 months (mean, 24.1 months). At last follow-up, the joint activity was (194.64 +/- 28.86) degrees, showing significant difference when compared with preoperative value (t = 25.214, P = 0.000). According to TAM assessment, including excellent in 1 finger, good in 4 fingers, fair in 7 fingers, and poor in 1 finger. The Sollerman score was 67.45 +/- 8.20 postoperatively, showing significant difference when compared with the preoperative score (t = -10.470, P = 0.000). X-ray examination showed no prosthesis fracture, periprosthetic fracture, or joint dislocation occurred at last follow-up. Swanson artificial joint replacement can be applied to treat post-traumatic metacarpophalangeal joint stiffness, which can improve the joint activity and has satisfactory short

Effect of range of motion in heavy load squatting on muscle and tendon adaptations

DEFF Research Database (Denmark)

Bloomquist, K; Langberg, Henning; Karlsen, Stine

2013-01-01

Manipulating joint range of motion during squat training may have differential effects on adaptations to strength training with implications for sports and rehabilitation. Consequently, the purpose of this study was to compare the effects of squat training with a short vs. a long range of motion...

Simultaneous estimation of human and exoskeleton motion: A simplified protocol.

Science.gov (United States)

Alvarez, M T; Torricelli, D; Del-Ama, A J; Pinto, D; Gonzalez-Vargas, J; Moreno, J C; Gil-Agudo, A; Pons, J L

2017-07-01

Adequate benchmarking procedures in the area of wearable robots is gaining importance in order to compare different devices on a quantitative basis, improve them and support the standardization and regulation procedures. Performance assessment usually focuses on the execution of locomotion tasks, and is mostly based on kinematic-related measures. Typical drawbacks of marker-based motion capture systems, gold standard for measure of human limb motion, become challenging when measuring limb kinematics, due to the concomitant presence of the robot. This work answers the question of how to reliably assess the subject's body motion by placing markers over the exoskeleton. Focusing on the ankle joint, the proposed methodology showed that it is possible to reconstruct the trajectory of the subject's joint by placing markers on the exoskeleton, although foot flexibility during walking can impact the reconstruction accuracy. More experiments are needed to confirm this hypothesis, and more subjects and walking conditions are needed to better characterize the errors of the proposed methodology, although our results are promising, indicating small errors.

Pronation-Supination Motion Is Altered in a Rat Model of Post-Traumatic Elbow Contracture.

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Dunham, Chelsey L; Castile, Ryan M; Chamberlain, Aaron M; Galatz, Leesa M; Lake, Spencer P

2017-07-01

The elbow joint is highly susceptible to joint contracture, and treating elbow contracture is a challenging clinical problem. Previously, we established an animal model to study elbow contracture that exhibited features similar to the human condition including persistent decreased range of motion (ROM) in flexion-extension and increased capsule thickness/adhesions. The objective of this study was to mechanically quantify pronation-supination in different injury models to determine if significant differences compared to control or contralateral persist long-term in our animal elbow contracture model. After surgically inducing soft tissue damage in the elbow, Injury I (anterior capsulotomy) and Injury II (anterior capsulotomy with lateral collateral ligament transection), limbs were immobilized for 6 weeks (immobilization (IM)). Animals were evaluated after the IM period or following an additional 6 weeks of free mobilization (FM). Total ROM for pronation-supination was significantly decreased compared to the uninjured contralateral limb for both IM and FM, although not different from control limbs. Specifically, for both IM and FM, total ROM for Injury I and Injury II was significantly decreased by ∼20% compared to contralateral. Correlations of measurements from flexion-extension and pronation-supination divulged that FM did not affect these motions in the same way, demonstrating that joint motions need to be studied/treated separately. Overall, injured limbs exhibited persistent motion loss in pronation-supination when comparing side-to-side differences, similar to human post-traumatic joint contracture. Future work will use this animal model to study how elbow periarticular soft tissues contribute to contracture.

Comparison of Joint Loading in Badminton Lunging between Professional and Amateur Badminton Players

Science.gov (United States)

Fu, Lin

2017-01-01

The knee and ankle are the two most injured joints associated with the sport of badminton. This study evaluates biomechanical factors between professional and amateur badminton players using an injury mechanism model. The aim of this study was to investigate the kinematic motion and kinetic loading differences of the right knee and ankle while performing a maximal right lunge. Amateur players exhibited greater ankle range of motion (p badminton players presented a greater knee joint moment in the sagittal (p badminton players should account for these findings to reduce potential injury to the ankle and knee. PMID:28694684

Dynamic response of tunnels in jointed rocks

International Nuclear Information System (INIS)

Heuze, F.E.; Shaffer, R.J.; Walton, O.R.; Maddix, D.M.

1992-03-01

We describe the application of the Discrete Element Method (DEM) to the dynamic analysis of the response of tunnels in jointed rocks to earthquake loading. In situations where large motions of many blocks and collapse occur, the discontinuum-based DEM approach appears superior to other methods of analysis

Kinematic control of redundant robots and the motion optimizability measure.

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Li, L; Gruver, W A; Zhang, Q; Yang, Z

2001-01-01

This paper treats the kinematic control of manipulators with redundant degrees of freedom. We derive an analytical solution for the inverse kinematics that provides a means for accommodating joint velocity constraints in real time. We define the motion optimizability measure and use it to develop an efficient method for the optimization of joint trajectories subject to multiple criteria. An implementation of the method for a 7-dof experimental redundant robot is present.

Anatomy of the distal knee joint and pyarthrosis following external fixation.

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Hyman, J; Moore, T

1999-05-01

To determine the limits of the distal synovial reflection of the human knee joint. Six paired knees studied by magnetic resonance imaging (MRI), fluoroscopic arthrography, and gross dissection. The right knees of five patients with chronic idiopathic knee effusions were studied by MRI. Cadaveric knees were injected with saline prior to MRI. The joint capsules were dissected to visualize local anatomy and check for capsular tears. In each modality (MRI, fluoroscopy, and dissection), the most distal extent of knee synovial fluid was measured. The right versus left agreement for paired specimens was generally two to three millimeters. Some specimens showed asymmetric capsular reflection. Medial fluid was identified at distances greater than forty-nine millimeters from the subchondral bone in seven knees and less than fifteen millimeters in four knees (range 0 to 70 millimeters, mean thirty-three millimeters). Laterally, the range was ten to thirty-five millimeters (mean twenty-three millimeters). In six of the twelve cadaveric specimens, there was evidence of a communication between the knee joint and the proximal tibiofibularjoint. In the knees of volunteers, joint fluid tracked medially to a range of ten to fifty millimeters and laterally to a range of six to fifteen millimeters, with means of twenty-six and eleven millimeters, respectively. The knees of the volunteers had no evidence of tibiofibular joint communication with the knee. Insertion of external fixation pins within sixty to seventy millimeters of the proximal articular surface of the tibia is associated with a high probability of synovial penetration and possibly provides a conduit for the introduction of bacteria, which may be etiologic in iatrogenic pyarthrosis.

Application of computer-assisted imaging technology in human musculoskeletal joint research

Directory of Open Access Journals (Sweden)

Xudong Liu

2014-01-01

Full Text Available Computer-assisted imaging analysis technology has been widely used in the musculoskeletal joint biomechanics research in recent years. Imaging techniques can accurately reconstruct the anatomic features of the target joint and reproduce its in vivo motion characters. The data has greatly improved our understanding of normal joint function, joint injury mechanism, and surgical treatment, and can provide foundations for using reverse-engineering methods to develop biomimetic artificial joints. In this paper, we systematically reviewed the investigation of in vivo kinematics of the human knee, shoulder, lumber spine, and ankle using advanced imaging technologies, especially those using a dual fluoroscopic imaging system (DFIS. We also briefly discuss future development of imaging analysis technology in musculoskeletal joint research.

Knee motion variability in patients with knee osteoarthritis: the effect of self-reported instability

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Gustafson, Jonathan A.; Robinson, Megan E.; Fitzgerald, G. Kelley; Tashman, Scott; Farrokhi, Shawn

2015-01-01

Background Knee osteoarthritis has been previously associated with a stereotypical knee-stiffening gait pattern and reduced knee joint motion variability due to increased antagonist muscle co-contractions and smaller utilized arc of motion during gait. However, episodic self-reported instability may be a sign of excessive motion variability for a large subgroup of patients with knee osteoarthritis. The objective of this work was to evaluate the differences in knee joint motion variability during gait in patients with knee osteoarthritis with and without self-reported instability compared to a control group of older adults with asymptomatic knees. Methods Forty-three subjects, 8 with knee osteoarthritis but no reports of instability (stable), 11 with knee osteoarthritis and self-reported instability (unstable), and 24 without knee osteoarthritis or instability (control) underwent Dynamic Stereo X-ray analysis during a decline gait task on a treadmill. Knee motion variability was assessed using parametric phase plots during the loading response phase of decline gait. Findings The stable group demonstrated decreased sagittal-plane motion variability compared to the control group (p=0.04), while the unstable group demonstrated increased sagittal-plane motion variability compared to the control (p=0.003) and stable groups (pknee motion variability in patients with knee osteoarthritis without self-reported instability supports previous research. However, presence of self-reported instability is associated with increased knee motion variability in patients with knee osteoarthritis and warrants further investigation. PMID:25796536

Evaluation of feature detection algorithms for structure from motion

CSIR Research Space (South Africa)

Govender, N

2009-11-01

Full Text Available technique with an application to stereo vision,” in International Joint Conference on Artificial Intelligence, April 1981. [17] C.Tomasi and T.Kanade, “Detection and tracking of point fetaures,” Carnegie Mellon, Tech. Rep., April 1991. [18] P. Torr... Algorithms for Structure from Motion Natasha Govender Mobile Intelligent Autonomous Systems CSIR Pretoria Email: ngovender@csir.co.za Abstract—Structure from motion is a widely-used technique in computer vision to perform 3D reconstruction. The 3D...

Lower limb joint work and joint work contribution during downhill and uphill walking at different inclinations.

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Alexander, Nathalie; Strutzenberger, Gerda; Ameshofer, Lisa Maria; Schwameder, Hermann

2017-08-16

Work performance and individual joint contribution to total work are important information for creating training protocols, but were not assessed so far for sloped walking. Therefore, the purpose of this study was to analyze lower limb joint work and joint contribution of the hip, knee and ankle to total lower limb work during sloped walking in a healthy population. Eighteen male participants (27.0±4.7yrs, 1.80±0.05m, 74.5±8.2kg) walked on an instrumented ramp at inclination angles of 0°, ±6°, ±12° and ±18° at 1.1m/s. Kinematic and kinetic data were captured using a motion-capture system (Vicon) and two force plates (AMTI). Joint power curves, joint work (positive, negative, absolute) and each joint's contribution to total lower limb work were analyzed throughout the stance phase using an ANOVA with repeated measures. With increasing inclination positive joint work increased for the ankle and hip joint and in total during uphill walking. Negative joint work increased for each joint and in total work during downhill walking. Absolute work was increased during both uphill (all joints) and downhill (ankle & knee) walking. Knee joint contribution to total negative and absolute work increased during downhill walking while hip and ankle contributions decreased. This study identified, that, when switching from level to a 6° and from 6° to a 12° inclination the gain of individual joint work is more pronounced compared to switching from 12° to an 18° inclination. The results might be used for training recommendations and specific training intervention with respect to sloped walking. Copyright © 2017 Elsevier Ltd. All rights reserved.

Design and Validation of Exoskeleton Actuated by Soft Modules toward Neurorehabilitation—Vision-Based Control for Precise Reaching Motion of Upper Limb

Directory of Open Access Journals (Sweden)

Victoria W. Oguntosin

2017-07-01

Full Text Available We demonstrated the design, production, and functional properties of the Exoskeleton Actuated by the Soft Modules (EAsoftM. Integrating the 3D printed exoskeleton with passive joints to compensate gravity and with active joints to rotate the shoulder and elbow joints resulted in ultra-light system that could assist planar reaching motion by using the vision-based control law. The EAsoftM can support the reaching motion with compliance realized by the soft materials and pneumatic actuation. In addition, the vision-based control law has been proposed for the precise control over the target reaching motion within the millimeter scale. Aiming at rehabilitation exercise for individuals, typically soft actuators have been developed for relatively small motions, such as grasping motion, and one of the challenges has been to extend their use for a wider range reaching motion. The proposed EAsoftM presented one possible solution for this challenge by transmitting the torque effectively along the anatomically aligned with a human body exoskeleton. The proposed integrated systems will be an ideal solution for neurorehabilitation where affordable, wearable, and portable systems are required to be customized for individuals with specific motor impairments.

Design and Validation of Exoskeleton Actuated by Soft Modules toward Neurorehabilitation-Vision-Based Control for Precise Reaching Motion of Upper Limb.

Science.gov (United States)

Oguntosin, Victoria W; Mori, Yoshiki; Kim, Hyejong; Nasuto, Slawomir J; Kawamura, Sadao; Hayashi, Yoshikatsu

2017-01-01

We demonstrated the design, production, and functional properties of the Exoskeleton Actuated by the Soft Modules (EAsoftM). Integrating the 3D printed exoskeleton with passive joints to compensate gravity and with active joints to rotate the shoulder and elbow joints resulted in ultra-light system that could assist planar reaching motion by using the vision-based control law. The EAsoftM can support the reaching motion with compliance realized by the soft materials and pneumatic actuation. In addition, the vision-based control law has been proposed for the precise control over the target reaching motion within the millimeter scale. Aiming at rehabilitation exercise for individuals, typically soft actuators have been developed for relatively small motions, such as grasping motion, and one of the challenges has been to extend their use for a wider range reaching motion. The proposed EAsoftM presented one possible solution for this challenge by transmitting the torque effectively along the anatomically aligned with a human body exoskeleton. The proposed integrated systems will be an ideal solution for neurorehabilitation where affordable, wearable, and portable systems are required to be customized for individuals with specific motor impairments.

Design and Validation of Exoskeleton Actuated by Soft Modules toward Neurorehabilitation—Vision-Based Control for Precise Reaching Motion of Upper Limb

Science.gov (United States)

Oguntosin, Victoria W.; Mori, Yoshiki; Kim, Hyejong; Nasuto, Slawomir J.; Kawamura, Sadao; Hayashi, Yoshikatsu

2017-01-01

We demonstrated the design, production, and functional properties of the Exoskeleton Actuated by the Soft Modules (EAsoftM). Integrating the 3D printed exoskeleton with passive joints to compensate gravity and with active joints to rotate the shoulder and elbow joints resulted in ultra-light system that could assist planar reaching motion by using the vision-based control law. The EAsoftM can support the reaching motion with compliance realized by the soft materials and pneumatic actuation. In addition, the vision-based control law has been proposed for the precise control over the target reaching motion within the millimeter scale. Aiming at rehabilitation exercise for individuals, typically soft actuators have been developed for relatively small motions, such as grasping motion, and one of the challenges has been to extend their use for a wider range reaching motion. The proposed EAsoftM presented one possible solution for this challenge by transmitting the torque effectively along the anatomically aligned with a human body exoskeleton. The proposed integrated systems will be an ideal solution for neurorehabilitation where affordable, wearable, and portable systems are required to be customized for individuals with specific motor impairments. PMID:28736514

Incidence of motion loss of the stifle joint in dogs with naturally occurring cranial cruciate ligament rupture surgically treated with tibial plateau leveling osteotomy: longitudinal clinical study of 412 cases.

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Jandi, Avtar S; Schulman, Alan J

2007-02-01

To report the incidence of loss of stifle extension or flexion and its relationship with clinical lameness after tibial plateau leveling osteotomy (TPLO) for treatment of cranial cruciate ligament (CCL) rupture. Longitudinal study. Dogs (n=280) with CCL rupture (n=412). TPLO was performed without meniscal release or arthrotomy. Angles of extension and flexion of the stifle were measured by goniometry to determine range of motion. Based upon motion loss, stifles were divided in 3 groups: no loss of extension or flexion (n=322), or =10 degrees loss of extension or flexion (n=12). Loss of extension or flexion > or =10 degrees was associated with significantly (P=.001) higher clinical lameness scores in comparison with no loss, or loss of extension or flexion or =10 degrees was less tolerable and less amenable to physical rehabilitation than flexion loss. Loss of extension or flexion > or =10 degrees was responsible for higher clinical lameness scores. Osteoarthrosis in the cranial femorotibial joint led to extension loss. Loss of extension or flexion should be assessed in dogs with persistent clinical lameness after TPLO so that early intervention can occur. Our study provides guidelines to define clinically relevant loss of extension or flexion of stifle joint after TPLO.

Effects of anatomic conformation on three-dimensional motion of the caudal lumbar and lumbosacral portions of the vertebral column of dogs.

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Benninger, Monika I; Seiler, Gabriela S; Robinson, Leanne E; Ferguson, Stephen J; Bonél, Harald M; Busato, André R; Lang, Johann

2006-01-01

To determine the association between the 3-dimensional (3-D) motion pattern of the caudal lumbar and lumbosacral portions of the canine vertebral column and the morphology of vertebrae, facet joints, and intervertebral disks. Vertebral columns of 9 German Shepherd Dogs and 16 dogs of other breeds with similar body weights and body conditions. Different morphometric parameters of the vertebral column were assessed by computed tomography (CT) and magnetic resonance imaging. Anatomic conformation and the 3-D motion pattern were compared, and correlation coefficients were calculated. Total range of motion for flexion and extension was mainly associated with the facet joint angle, the facet joint angle difference between levels of the vertebral column in the transverse plane on CT images, disk height, and lever arm length. Motion is a complex process that is influenced by the entire 3-D conformation of the lumbar portion of the vertebral column. In vivo dynamic measurements of the 3-D motion pattern of the lumbar and lumbosacral portions of the vertebral column will be necessary to further assess biomechanics that could lead to disk degeneration in dogs.

A STUDY ON PROXIMAL HUMERAL FRACTURES STABILISED WITH PHILOS PLATE

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Praveen Sivakumar K

2017-02-01

Full Text Available BACKGROUND Techniques for treating complex proximal humeral fractures vary and include fixations using tension bands, percutaneous pins, bone suture, T-plates, intramedullary nails, double tubular plates, hemiarthroplasty, plant tan humerus fixator plates, Polaris nails and blade plates. Complications of these techniques include cutout or back out of the screws and plates, avascular necrosis, nonunion, malunion, nail migration, rotator cuff impairment and impingement syndromes. Insufficient anchorage from conventional implants may lead to early loosening and failure, especially in osteoporotic bones. In general, nonoperative treatment of displaced three and four-part fractures of the proximal humerus leads to poor outcome due to intraarticular nature of injury and inherent instability of the fragments. Comminuted fractures of the proximal humerus are at risk of fixation failure, screw loosening and fracture displacement. Open reduction and internal fixation with conventional plate and screws has been associated with unacceptably high incidence of screw pull out. PHILOS (the proximal humeral internal locking system plate is an internal fixation system that enables angled stabilisation with multiple interlocking screws for fractures of the proximal humerus. MATERIALS AND METHODS 30 patients with proximal humerus fractures who were admitted in the Department of Orthopaedics, Government General Hospital, Kakinada, during the period November 2014 - November 2016 were taken up for study according to inclusion criteria. All patients were treated with PHILOS plate. These proximal humerus fractures were classified according to Neer’s classification. Patients were followed up at 6 weeks, 12 weeks and 6 months’ interval. Functional outcomes for pain, range of motion and muscle power and function were assessed using the Constant-Murley scoring system. Collected data analysed with independent t-test and ANNOVA test. RESULTS The outcome of the study was 1

Validation of the Leap Motion Controller using markered motion capture technology.

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Smeragliuolo, Anna H; Hill, N Jeremy; Disla, Luis; Putrino, David

2016-06-14

The Leap Motion Controller (LMC) is a low-cost, markerless motion capture device that tracks hand, wrist and forearm position. Integration of this technology into healthcare applications has begun to occur rapidly, making validation of the LMC׳s data output an important research goal. Here, we perform a detailed evaluation of the kinematic data output from the LMC, and validate this output against gold-standard, markered motion capture technology. We instructed subjects to perform three clinically-relevant wrist (flexion/extension, radial/ulnar deviation) and forearm (pronation/supination) movements. The movements were simultaneously tracked using both the LMC and a marker-based motion capture system from Motion Analysis Corporation (MAC). Adjusting for known inconsistencies in the LMC sampling frequency, we compared simultaneously acquired LMC and MAC data by performing Pearson׳s correlation (r) and root mean square error (RMSE). Wrist flexion/extension and radial/ulnar deviation showed good overall agreement (r=0.95; RMSE=11.6°, and r=0.92; RMSE=12.4°, respectively) with the MAC system. However, when tracking forearm pronation/supination, there were serious inconsistencies in reported joint angles (r=0.79; RMSE=38.4°). Hand posture significantly influenced the quality of wrist deviation (P<0.005) and forearm supination/pronation (P<0.001), but not wrist flexion/extension (P=0.29). We conclude that the LMC is capable of providing data that are clinically meaningful for wrist flexion/extension, and perhaps wrist deviation. It cannot yet return clinically meaningful data for measuring forearm pronation/supination. Future studies should continue to validate the LMC as updated versions of their software are developed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Knock-in human GDF5 proregion L373R mutation as a mouse model for proximal symphalangism.

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Zhang, Xinxin; Xing, Xuesha; Liu, Xing; Hu, Yu; Qu, Shengqiang; Wang, Heyi; Luo, Yang

2017-12-26

Proximal symphalangism (SYM1) is an autosomal dominant disorder, mainly characterized by bony fusions of the proximal phalanges of the hands and feet. GDF5 and NOG were identified to be responsible for SYM1. We have previously reported on a p.Leu373Arg mutation in the GDF5 proregion present in a Chinese family with SYM1. Here, we investigated the effects of the GDF-L373R mutation. The variant caused proteolysis efficiency of GDF5 increased in ATDC5 cells. The variant also caused upregulation of SMAD1/5/8 phosphorylation and increased expression of target genes SMURF1 , along with COL2A1 and SOX9 which are factors associated with chondrosis. Furthermore, we developed a human-relevant SYM1 mouse model by making a Gdf5 L367R (the orthologous position for L373R in humans) knock-in mouse. Gdf5 L367R/+ and Gdf5 L367R/L367R mice displayed stiffness and adhesions across the proximal phalanx joint which were in complete accord with SYM1. It was also confirmed the joint formation and development was abnormal in Gdf5 L367R/+ and Gdf5 L367R/L367R mice, including the failure to develop the primary ossification center and be hypertrophic chondrocytes during embryonic development. This knock-in mouse model offers a tool for assessing the pathogenesis of SYM1 and the function of the GDF5 proregion.

Subtalar joint stress imaging with tomosynthesis.

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Teramoto, Atsushi; Watanabe, Kota; Takashima, Hiroyuki; Yamashita, Toshihiko

2014-06-01

The purpose of this study was to perform stress imaging of hindfoot inversion and eversion using tomosynthesis and to assess the subtalar joint range of motion (ROM) of healthy subjects. The subjects were 15 healthy volunteers with a mean age of 29.1 years. Coronal tomosynthesis stress imaging of the subtalar joint was performed in a total of 30 left and right ankles. A Telos stress device was used for the stress load, and the load was 150 N for both inversion and eversion. Tomographic images in which the posterior talocalcaneal joint could be confirmed on the neutral position images were used in measurements. The angle of the intersection formed by a line through the lateral articular facet of the posterior talocalcaneal joint and a line through the surface of the trochlea of the talus was measured. The mean change in the angle of the calcaneus with respect to the talus was 10.3 ± 4.8° with inversion stress and 5.0 ± 3.8° with eversion stress from the neutral position. The result was a clearer depiction of the subtalar joint, and inversion and eversion ROM of the subtalar joint was shown to be about 15° in healthy subjects. Diagnostic, Level IV.

Prevalence of joint contractures and muscle weakness in people with multiple sclerosis.

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Hoang, Phu Dinh; Gandevia, Simon C; Herbert, Robert D

2014-01-01

To investigate the prevalence of joint contracture (limited passive range of joint motion) and muscle weakness in a population with multiple sclerosis (MS). A secondary aim was to establish normative data of functional tests of mobility and balance of people with MS who are still ambulant. Cross-sectional study. People with MS living in metropolitan Sydney, Australia. 330 people with MS living in metropolitan Sydney, Australia were randomly sampled on 23 July 2009 from the MS Australia register and invited to participate. Passive range of motion of large joints of the limbs and muscle strength. Tests of walking and balance were also conducted. 156 people (109 females, 47 males; mean age 54.2 years; mean time since diagnosis 14.9 years) agreed to participate and were assessed. Fifty-six per cent (56%) of participants had contracture in at least one major joint of upper or lower limb. The most common site of contracture was the ankle (43.9%). Seventy per cent (70%) of participants had muscle weakness in one or more muscle groups. As muscle weakness, joint contractures were present at early stage of MS and the prevalence was associated with the progression of the disease. These data show that in addition to muscle weakness joint contractures are highly prevalent among people with MS, especially in the ankle joint. This implicates that prevention of contracture is crucial in providing rehabilitation to people with MS.

Comparison of 3-Dimensional Shoulder Complex Kinematics in Individuals With and Without Shoulder Pain, Part 1: Sternoclavicular, Acromioclavicular, and Scapulothoracic Joints

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LAWRENCE, REBEKAH L.; BRAMAN, JONATHAN P.; LAPRADE, ROBERT F.; LUDEWIG, PAULA M.

2015-01-01

STUDY DESIGN Cross-sectional. OBJECTIVES To compare sternoclavicular, acromioclavicular, and scapulothoracic joint motion between symptomatic and asymptomatic individuals during shoulder motion performed in 3 planes of humerothoracic elevation. BACKGROUND Differences in scapulothoracic kinematics are associated with shoulder pain. Several studies have measured these differences using surface sensors, but the results of this technique may be affected by skin-motion artifact. Furthermore, previous studies have not included the simultaneous measurement of sternoclavicular and acromioclavicular joint motion. METHODS Transcortical bone pins were inserted into the clavicle, scapula, and humerus of 12 asymptomatic and 10 symptomatic individuals for direct, bone-fixed tracking using electromagnetic sensors. Angular positions for the sternoclavicular, acromioclavicular, and scapulothoracic joints were measured during shoulder flexion, abduction, and scapular plane abduction. RESULTS Differences between groups were found for sternoclavicular and scapulothoracic joint positions. Symptomatic individuals consistently demonstrated less sternoclavicular posterior rotation, regardless of angle, phase, or plane of shoulder motion. Symptomatic individuals also demonstrated less scapulothoracic upward rotation at 30° and 60° of humerothoracic elevation during shoulder abduction and scapular plane abduction. CONCLUSION The results of this study show that differences in shoulder complex kinematics exist between symptomatic and asymptomatic individuals. However, the magnitude of these differences was small, and the resulting clinical implications are not yet fully understood. The biomechanical coupling of the sternoclavicular and acromioclavicular joints requires further research to better understand scapulothoracic movement deviations and to improve manual therapy and exercise-based physical therapy interventions. PMID:25103135

The efficacy of manual joint mobilisation/manipulation in treatment of lateral ankle sprains: a systematic review.

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Loudon, Janice K; Reiman, Michael P; Sylvain, Jonathan

2014-03-01

Lateral ankle sprains are common and can have detrimental consequences to the athlete. Joint mobilisation/manipulation may limit these outcomes. Systematically summarise the effectiveness of manual joint techniques in treatment of lateral ankle sprains. This review employed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A computer-assisted literature search of MEDLINE, CINHAL, EMBASE, OVID and Physiotherapy Evidence Database (PEDro) (January 1966 to March 2013) was used with the following keywords alone and in combination 'ankle', 'sprain', 'injuries', 'lateral', 'manual therapy', and 'joint mobilisation'. The methodological quality of individual studies was assessed using the PEDro scale. After screening of titles, abstracts and full articles, eight articles were kept for examination. Three articles achieved a score of 10 of 11 total points; one achieved a score of 9; two articles scored 8; one article scored a 7 and the remaining article scored a 5. Three articles examined joint techniques for acute sprains and the remainder examined subacute/chronic ankle sprains. Outcome measures included were pain level, ankle range of motion, swelling, functional score, stabilometry and gait parameters. The majority of the articles only assessed these outcome measures immediately after treatment. No detrimental effects from the joint techniques were revealed in any of the studies reviewed. For acute ankle sprains, manual joint mobilisation diminished pain and increased dorsiflexion range of motion. For treatment of subacute/chronic lateral ankle sprains, these techniques improved ankle range-of-motion, decreased pain and improved function.

Smartphone-based accelerometry is a valid tool for measuring dynamic changes in knee extension range of motion

DEFF Research Database (Denmark)

Støve, Morten Pallisgaard; Palsson, Thorvaldur Skuli; Hirata, Rogerio Pessoto

2018-01-01

Introduction: Measurement of static joint range of motion is used extensively in orthopaedic and rehabilitative communities to benchmark treatment efficacy. Static measures are, however, insufficient in providing detailed information about patient impairments. Dynamic range of motion measures cou...

Evaluation of the magnitude of hip joint deformation in subjects with avascular necrosis of the hip joint during walking with and without Scottish Rite orthosis.

Science.gov (United States)

Karimi, Mohammad Taghi; Mohammadi, Ali; Ebrahimi, Mohammad Hossein; McGarry, Anthony

2017-02-01

The femoral head in subjects with leg calve perthes disease (LCPD) is generally considerably deformed. It is debatable whether this deformation is due to an increase in applied loads, a decrease in bone mineral density or a change in containment of articular surfaces. The aim of this study was to determine the influence of these factors on deformation of the femoral head. Two subjects with LCPD participated in this study. Subject motion and the forces applied on the affected leg were recorded using a motion analysis system (Qualsis TM ) and a Kistler force plate. OpenSim software was used to determine joint contact force of the hip joint whilst walking with and without a Scottish Rite orthosis. 3D Models of hip joints of both subjects were produced by Mimics software. The deformation of femoral bone was determined by Abaqus. Mean values of the force applied on the leg increased while walking with the orthosis. There was no difference between bone mineral density (BMD) of the femoral bone of normal and LCPD sides (p-value>0.05) and no difference between hip joint contact force of normal and LCPD sides. Hip joint containment appeared to decrease follow the use of the orthosis. It can be concluded that the deformation of femoral head in LCPD may not be due to change in BMD or applied load. Although the Scottish Rite orthosis is used mostly to increase hip joint containment, it appears to reduce hip joint contact area. It is recommended that a similar study is conducted using a higher number of subjects. Copyright © 2016 IPEM. All rights reserved.

Biomechanical design of escalading lower limb exoskeleton with novel linkage joints.

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Zhang, Guoan; Liu, Gangfeng; Ma, Sun; Wang, Tianshuo; Zhao, Jie; Zhu, Yanhe

2017-07-20

In this paper, an obstacle-surmounting-enabled lower limb exoskeleton with novel linkage joints that perfectly mimicked human motions was proposed. Currently, most lower exoskeletons that use linear actuators have a direct connection between the wearer and the controlled part. Compared to the existing joints, the novel linkage joint not only fitted better into compact chasis, but also provided greater torque when the joint was at a large bend angle. As a result, it extended the angle range of joint peak torque output. With any given power, torque was prioritized over rotational speed, because instead of rotational speed, sufficiency of torque is the premise for most joint actions. With insufficient torque, the exoskeleton will be a burden instead of enhancement to its wearer. With optimized distribution of torque among the joints, the novel linkage method may contribute to easier exoskeleton movements.

Simultaneous two-view epipolar geometry estimation and motion segmentation by 4D tensor voting.

Science.gov (United States)

Tong, Wai-Shun; Tang, Chi-Keung; Medioni, Gérard

2004-09-01

We address the problem of simultaneous two-view epipolar geometry estimation and motion segmentation from nonstatic scenes. Given a set of noisy image pairs containing matches of n objects, we propose an unconventional, efficient, and robust method, 4D tensor voting, for estimating the unknown n epipolar geometries, and segmenting the static and motion matching pairs into n independent motions. By considering the 4D isotropic and orthogonal joint image space, only two tensor voting passes are needed, and a very high noise to signal ratio (up to five) can be tolerated. Epipolar geometries corresponding to multiple, rigid motions are extracted in succession. Only two uncalibrated frames are needed, and no simplifying assumption (such as affine camera model or homographic model between images) other than the pin-hole camera model is made. Our novel approach consists of propagating a local geometric smoothness constraint in the 4D joint image space, followed by global consistency enforcement for extracting the fundamental matrices corresponding to independent motions. We have performed extensive experiments to compare our method with some representative algorithms to show that better performance on nonstatic scenes are achieved. Results on challenging data sets are presented.

Digital tomosynthesis rendering of joint margins for arthritis assessment

Science.gov (United States)

Duryea, Jeffrey W.; Neumann, Gesa; Yoshioka, Hiroshi; Dobbins, James T., III

2004-05-01

PURPOSE: Rheumatoid arthritis (RA) of the hand is a significant healthcare problem. Techniques to accurately quantity the structural changes from RA are crucial for the development and prescription of therapies. Analysis of radiographic joint space width (JSW) is widely used and has demonstrated promise. However, radiography presents a 2D view of the joint. In this study we performed tomosynthesis reconstructions of proximal interphalangeal (PIP), and metacarpophalangeal (MCP) joints to measure the 3D joint structure. METHODS: We performed a reader study using simulated radiographs of 12 MCP and 12 PIP joints from skeletal specimens imaged with micro-CT. The tomosynthesis technique provided images of reconstructed planes with 0.75 mm spacing, which were presented to 2 readers with a computer tool. The readers were instructed to delineate the joint surfaces on tomosynthetic slices where they could visualize the margins. We performed a quantitative analysis of 5 slices surrounding the central portion of each joint. Reader-determined JSW was compared to a gold standard. As a figure of merit we calculated the average root-mean square deviation (RMSD). RESULTS: RMSD was 0.22 mm for both joints. For the individual joints, RMSD was 0.18 mm (MCP), and 0.26 mm (PIP). The reduced performance for the smaller PIP joints suggests that a slice spacing less than 0.75 mm may be more appropriate. CONCLUSIONS: We have demonstrated the capability of limited 3D rendering of joint surfaces using digital tomosynthesis. This technique promises to provide an improved method to visualize the structural changes of RA.

[Osteoarthritic changes in hip joint in patients with fractures of femoral neck].

Science.gov (United States)

Kravtsov, Vladimir; Saranga, Dan; Kidron, Debora

2013-06-01

Fractures of proximal femur are common among elderly people. They are associated with considerable morbidity and mortality. Identification of etiopathogenetic factors associated with fractures might facilitate prevention. Osteoporosis is commonly present in the heads of femurs. The prevalence of osteoarthritic changes in hip joints is controversial. Some authorities report low prevalence and even speculate on the protective effect of osteoarthritis against fractures. The goal of the study was to examine the association between osteoarthritic changes (radiologic and histologic) and fractures of the neck of the femur. The patient population included 41 patients undergoing replacement of femoral head for subcapital fracture; their ages ranged from 61 - 93 years of age. Radiologic criteria for osteoarthritis included: (a)narrowing of joint space (b) subchondral sclerosis (c) deformation of head of femur (d) subchondra cysts and (e] osteophytes. Osteoarthritic changes, usually mild, were present in 22 (54%) patients, regardless of age and gender The frequency of radioLogical changes was similar to the general population. HistoLogic findings included subchondral fibrosis and subchondral cysts. Mild subchondral fibrosis was present in 78% of cases. The findings support lack of association between osteoarthritic changes in hip joint and fracture of proximal femur, without a protective effect.

Immediate Effects of Anterior-to-Posterior Talocrural Joint Mobilization after Prolonged Ankle Immobilization: A Preliminary Study

OpenAIRE

Landrum, Elizabeth L.; Kelln, Cdr. Brent M.; Parente, William R.; Ingersoll, Christopher D.; Hertel, Jay

2008-01-01

Ankle dorsiflexion range of motion (ROM) typically decreases after prolonged immobilization. Anterior-to-posterior talocrural joint mobilizations are purported to increase dorsiflexion ROM and decrease joint stiffness after immobilization. The purpose of this study was to determine if a single bout of Grade III anterior-to-posterior talocrural joint mobilizations immediately affected measures of dorsiflexion ROM, posterior ankle joint stiffness, and posterior talar translation in ankles of pa...

Incomplete longitudinal fracture of the proximal palmar cortex of the third metacarpal bone in horses

International Nuclear Information System (INIS)

Ross, M.W.; Ford, T.S.; Orsini, P.G.

1988-01-01

Seven horses, 2 to 4 years of age, were examined because of moderate-to-severe forelimb lameness, mild effusion of the middle carpal joint (3 horses), and pain on palpation of the origin of the suspensory ligament (4 horses). The lameness was abolished by anesthetic infiltration of the middle carpal joint in six horses. In four of them, a high palmar nerve block also abolished the lameness. A linear radiolucency in the proximal end of the third metacarpal bone (McIII) was interpreted as an incomplete longitudinal fracture. In one horse, distinct intramedullary sclerosis limited to the palmar cortex was indicative of an incomplete fracture confined to the palmar cortex. No osteoproliferative lesions were identified on the dorsal cortex of any of the horses. Surgical treatment with cortical screws in lag fashion accompanied by a rest period was successful in one horse. In four horses, rest for at least 3 months resulted in clinical soundness. In two horses, a shorter rest period resulted in recurrence of the lameness even though the horses were sound when put back into training. Careful clinical and radiographic examinations helped differentiate incomplete longitudinal fractures from lesions involving the carpus and proximal aspect of the suspensory ligament

Distraction lengthening of the proximal phalanx in distal thumb amputations.

Science.gov (United States)

Cansü, Eren; Ünal, Mehmet Bekir; Parmaksızoğlu, Fatih; Gürcan, Serkan

2015-01-01

Thumb amputation is a major cause of hand dysfunction, and the treatment for distal thumb amputations remains controversial. Although finger reconstruction methods using distraction lengthening are known to restore finger length and function, we found no reports in the literature regarding phalangeal lengthening in thumb amputations. We aimed to evaluate proximal phalangeal lengthening in thumb amputations at or near the interphalangeal (IP) joint. We retrospectively evaluated patients who had undergone distraction lengthening of the proximal phalanx of the thumb. All patients underwent osteotomy, either during the initial procedure or as a second-stage procedure. Distraction began 10 days after osteotomy with the use of an external fixator that remained in place until ossification of the gap occurred without bone grafting. Patients were evaluated using the QuickDASH score. Fourteen patients with a mean age of 27 years and a mean follow-up period of 7 years were enrolled. The mean phalangeal lengthening achieved was 20 mm. Ossification occurred at all distraction sites, and the fixators were maintained for a mean of 85 days. The mean healing index was 42.5 days/cm. All 14 patients achieved the desired amount of phalangeal lengthening without major complications such as nonunion, premature union, or gross infection. For reconstruction in cases of distal thumb amputations, distraction lengthening of the proximal phalanx can be used to improve absolute length, web space, and grip distance. The technique is safe and effective, improves functionality/cosmesis, and offers a low complication risk.

Case report 390: Tuberculous pseudotumor of the proximal end of the right tibia without obvious synovial involvement

Energy Technology Data Exchange (ETDEWEB)

Abdelwahab, I.F.; Present, D.A.; Klein, M.J.

1986-11-01

A case of osseous tuberculosis has been presented in a young black man who was known to be an addict to cocaine. An osteolytic lesion involved the proximal end of the tibia, being eccentric and subarticular in location. The knee joint spaces were intact, suggesting that no obvious involvement of the cartilages was present. Thus, neoplastic lesions such as chondroblastoma and giant cell tumor were considered in the differential diagnosis of the lesion which appeared to be benign radiologically. The lesion proved to be tuberculous in nature, with intact knee joint cartilages. A diagnosis of tuberculous 'pseudotumor' might be used aptly. (orig./SHA).

Predicting kinetics using musculoskeletal modeling and inertial motion capture

NARCIS (Netherlands)

Karatsidis, Angelos; Jung, Moonki; Schepers, H. Martin; Bellusci, Giovanni; de Zee, Mark; Veltink, Peter H.; Andersen, Michael Skipper

2018-01-01

Inverse dynamic analysis using musculoskeletal modeling is a powerful tool, which is utilized in a range of applications to estimate forces in ligaments, muscles, and joints, non-invasively. To date, the conventional input used in this analysis is derived from optical motion capture (OMC) and force

Using Motion Tracking to Detect Spontaneous Movements in Infants

DEFF Research Database (Denmark)

Olsen, Mikkel Damgaard; Herskind, Anna; Nielsen, Jens Bo

2015-01-01

We study the characteristics of infants’ spontaneous movements, based on data obtained from a markerless motion tracking system. From the pose data, the set of features are generated from the raw joint-angles of the infants and different classifiers are trained and evaluated using annotated data...

First Metatarsophalangeal Contact Properties Following Proximal Opening Wedge and Scarf Osteotomies for Hallux Valgus Correction: A Biomechanical Study.

Science.gov (United States)

Kia, Cameron; Yoshida, Ryu; Cote, Mark; DiVenere, Jessica; Geaney, Lauren E

2017-04-01

Proximal opening wedge osteotomy (POWO) is an established procedure for moderate to severe hallux valgus. A common concern of this procedure is that it results in lengthening of the first metatarsal, which could cause increased intra-articular pressure of the first metatarsophalangeal joint (MTP) and may ultimately lead to arthritis because of these altered mechanics. The purpose of this study was to use a cadaveric model to compare intra-articular pressures and articulating contact properties of the MTP joint following either scarf osteotomy or POWO. Fresh-frozen cadaveric below-knee specimens with pre-existing hallux valgus (n = 12) and specimens without hallux valgus (n = 6, control group) were used. The hallux valgus specimens were stratified into 2 groups (n = 6 each): POWO or scarf osteotomy. The groups were matched based on the degree of deformity. Peak intra-articular pressure, force, and area were measured in all normal, preoperative, and postoperative specimens with a simulated weightbearing model. These measurements were made with a pressure transducer placed within the first MTP joint. Postoperatively POWO group had slightly higher contact forces and pressures compared to the scarf group and lower contact forces and pressures than those of the normal group but were not statistically significant ( P > .05). Normal specimens had higher intra-articular force, pressure, and area than postoperative specimens but the difference was not found to be significant. First metatarsal lengthening was found in both the scarf and POWO specimens; however, neither increase was found to be significant ( P > .05). The results from this study show that after operative correction, contact properties of the fist MTP joint among normal, POWO, and scarf osteotomy groups revealed no significant differences. First MTP joints in those with hallux valgus had significantly lower contact force and pressure compared to those without hallux valgus. With little long-term outcomes of

IMU-Based Joint Angle Measurement for Gait Analysis

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Thomas Seel

2014-04-01

Full Text Available This contribution is concerned with joint angle calculation based on inertial measurement data in the context of human motion analysis. Unlike most robotic devices, the human body lacks even surfaces and right angles. Therefore, we focus on methods that avoid assuming certain orientations in which the sensors are mounted with respect to the body segments. After a review of available methods that may cope with this challenge, we present a set of new methods for: (1 joint axis and position identification; and (2 flexion/extension joint angle measurement. In particular, we propose methods that use only gyroscopes and accelerometers and, therefore, do not rely on a homogeneous magnetic field. We provide results from gait trials of a transfemoral amputee in which we compare the inertial measurement unit (IMU-based methods to an optical 3D motion capture system. Unlike most authors, we place the optical markers on anatomical landmarks instead of attaching them to the IMUs. Root mean square errors of the knee flexion/extension angles are found to be less than 1° on the prosthesis and about 3° on the human leg. For the plantar/dorsiflexion of the ankle, both deviations are about 1°.

The independent effects of speed and propulsive force on joint power generation in walking.

Science.gov (United States)

Browne, Michael G; Franz, Jason R

2017-04-11

Walking speed is modulated using propulsive forces (F P ) during push-off and both preferred speed and F P decrease with aging. However, even prior to walking slower, reduced F P may be accompanied by potentially unfavorable changes in joint power generation. For example, compared to young adults, older adults exhibit a redistribution of mechanical power generation from the propulsive plantarflexor muscles to more proximal muscles acting across the knee and hip. Here, we used visual biofeedback based on real-time F P measurements to decouple and investigate the interaction between joint-level coordination, whole-body F P , and walking speed. 12 healthy young subjects walked on a dual-belt instrumented treadmill at a range of speeds (0.9-1.3m/s). We immediately calculated the average F P from each speed. Subjects then walked at 1.3m/s while completing a series of biofeedback trials with instructions to match their instantaneous F P to their averaged F P from slower speeds. Walking slower decreased F P and total positive joint work with little effect on relative joint-level contributions. Conversely, subjects walked at a constant speed with reduced F P , not by reducing total positive joint work, but by redistributing the mechanical demands of each step from the plantarflexor muscles during push-off to more proximal leg muscles during single support. Interestingly, these naturally emergent joint- and limb-level biomechanical changes, in the absence of neuromuscular constraints, resemble those due to aging. Our findings provide important reference data to understand the presumably complex interactions between joint power generation, whole-body F P , and walking speed in our aging population. Copyright © 2017 Elsevier Ltd. All rights reserved.

Biomechanical model-based displacement estimation in micro-sensor motion capture

International Nuclear Information System (INIS)

Meng, X L; Sun, S Y; Wu, J K; Zhang, Z Q; 3 Building, 21 Heng Mui Keng Terrace (Singapore))" data-affiliation=" (Department of Electrical and Computer Engineering, National University of Singapore (NUS), 02-02-10 I3 Building, 21 Heng Mui Keng Terrace (Singapore))" >Wong, W C

2012-01-01

In micro-sensor motion capture systems, the estimation of the body displacement in the global coordinate system remains a challenge due to lack of external references. This paper proposes a self-contained displacement estimation method based on a human biomechanical model to track the position of walking subjects in the global coordinate system without any additional supporting infrastructures. The proposed approach makes use of the biomechanics of the lower body segments and the assumption that during walking there is always at least one foot in contact with the ground. The ground contact joint is detected based on walking gait characteristics and used as the external references of the human body. The relative positions of the other joints are obtained from hierarchical transformations based on the biomechanical model. Anatomical constraints are proposed to apply to some specific joints of the lower body to further improve the accuracy of the algorithm. Performance of the proposed algorithm is compared with an optical motion capture system. The method is also demonstrated in outdoor and indoor long distance walking scenarios. The experimental results demonstrate clearly that the biomechanical model improves the displacement accuracy within the proposed framework. (paper)

System analysis of sagittal plane human motion wearing an exoskeleton using marker technology

Directory of Open Access Journals (Sweden)

Jatsun Sergey

2016-01-01

Full Text Available This paper discusses various methods of obtaining time functions for joint angle that describe a exoskeleton’s motion during sit-to-stand motion. This article demonstrates that functions obtained by solving the inverse kinematics problem can be effectively used as inputs to the control system of the robot. Comparison with experimentally data obtained using marker technology is done.

Demonstration of movement in the sacroiliac joint using ultrasound

Science.gov (United States)

Krupinski, Elizabeth A.; Brooks, William J.; Lund, Pamela J.

1995-05-01

The goal of this study was to demonstrate quantitatively, using ultrasound (US) recording techniques, the extent of motion of the sacroiliac joint achieved using manual medicine techniques. Initial judgements of perceived (i.e., felt) SI mobility during manual examination were made on 22 subjects. Baseline no movement ultrasound images (static) were obtained of the left and right SI joints at two levels-- posterior-superior-iliac-spine and inferior (PSIS, INF)--and two projections (AP and LAT). Manual medicine spring testing of the SI joint was then performed while ultrasound recordings (on video) were made. The differences between baseline separation of the SI joint and displacement distance during spring testing were measured by six radiologists who typically read US images. Significant movement of at least one SI joint was demonstrated in 91% of the subjects using ultrasound recordings. The extent of movement appeared to corroborate the experience of manual medicine practitioners.

Proximal Alternating Direction Method with Relaxed Proximal Parameters for the Least Squares Covariance Adjustment Problem

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Minghua Xu

2014-01-01

Full Text Available We consider the problem of seeking a symmetric positive semidefinite matrix in a closed convex set to approximate a given matrix. This problem may arise in several areas of numerical linear algebra or come from finance industry or statistics and thus has many applications. For solving this class of matrix optimization problems, many methods have been proposed in the literature. The proximal alternating direction method is one of those methods which can be easily applied to solve these matrix optimization problems. Generally, the proximal parameters of the proximal alternating direction method are greater than zero. In this paper, we conclude that the restriction on the proximal parameters can be relaxed for solving this kind of matrix optimization problems. Numerical experiments also show that the proximal alternating direction method with the relaxed proximal parameters is convergent and generally has a better performance than the classical proximal alternating direction method.

The validity of the first and second generation Microsoft Kinect™ for identifying joint center locations during static postures.

Science.gov (United States)

Xu, Xu; McGorry, Raymond W

2015-07-01

The Kinect™ sensor released by Microsoft is a low-cost, portable, and marker-less motion tracking system for the video game industry. Since the first generation Kinect sensor was released in 2010, many studies have been conducted to examine the validity of this sensor when used to measure body movement in different research areas. In 2014, Microsoft released the computer-used second generation Kinect sensor with a better resolution for the depth sensor. However, very few studies have performed a direct comparison between all the Kinect sensor-identified joint center locations and their corresponding motion tracking system-identified counterparts, the result of which may provide some insight into the error of the Kinect-identified segment length, joint angles, as well as the feasibility of adapting inverse dynamics to Kinect-identified joint centers. The purpose of the current study is to first propose a method to align the coordinate system of the Kinect sensor with respect to the global coordinate system of a motion tracking system, and then to examine the accuracy of the Kinect sensor-identified coordinates of joint locations during 8 standing and 8 sitting postures of daily activities. The results indicate the proposed alignment method can effectively align the Kinect sensor with respect to the motion tracking system. The accuracy level of the Kinect-identified joint center location is posture-dependent and joint-dependent. For upright standing posture, the average error across all the participants and all Kinect-identified joint centers is 76 mm and 87 mm for the first and second generation Kinect sensor, respectively. In general, standing postures can be identified with better accuracy than sitting postures, and the identification accuracy of the joints of the upper extremities is better than for the lower extremities. This result may provide some information regarding the feasibility of using the Kinect sensor in future studies. Copyright © 2015 Elsevier

Ipsilateral stress fracture of the proximal fibula after total knee arthroplasty in a patient with severe valgus knee deformity on a background of Rheumatoid arthritis

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Hirokazu Takai

Full Text Available Introduction: Previous studies have reported a lower extremity stress fracture after total knee arthroplasty (TKA. However, a fibular fracture after TKA is quite rare. We report a case of proximal fibula fracture after TKA in a patient with rheumatoid arthritis (RA. Presentation of case: A 45 year old woman with RA had severe knee and foot pain with an antalgic gait disturbance. There was a significant joint deformity in many of lower limb joints. Interval bilateral TKAs were performed two weeks apart. Right TKA was performed using a constraint-type prosthesis, through lateral parapatellar approach. Left TKA was performed using a posterior-stabilized (PS prosthesis through the more commonly employed, medial parapatellar approach. Seven weeks after the right TKA, the patient was found to have an atraumatic proximal fibular fracture. The fracture went on to heal conservatively. Discussion: The fracture was considered to have occurred after the TKA. The callus appeared eleven weeks after the TKA. The factors that contributed to the fracture were thought to be overload of the fragile bone secondarily to disuse osteopaenia, RA or potentially the significant valgus malalignment correction. The surgical approach, the implant or implantation or the persisting joint deformity, were thought to be contributing factors to the aetiology of the stress fracture. The resultant change in clinical outcome/course is outlined in this case report. Conclusion: A stress fracture of the proximal fibula has the potential in the aetiology of may cause other stress fractures, joint other instability, and/or malalignment of the total lower extremity. Keywords: Stress fracture, Insufficiency fracture, Total knee arthroplasty, Fibula fracture, Valgus deformity, Rheumatoid arthritis

Four Weeks of Mobility After 8 Weeks of Immobility Fails to Restore Normal Motion

Science.gov (United States)

Trudel, Guy; Zhou, Jian; Uhthoff, Hans K.

2008-01-01

Prolonged immobilization reduces passive range of motion of joints creating joint contractures. Whether and to what extent these iatrogenic contractures can be reduced is unknown. We raised three questions using an animal model: What degree of contracture remains at the end of a defined remobilization period? Do contractures in sham-operated and immobilized joints differ? What is the contribution of the posterior knee capsule in limiting knee extension? We immobilized one knee of 11 adult male rats in flexion to induce a joint contracture; 10 control animals underwent a sham operation. After 8 weeks, the internal fixation device was removed, and the animals were allowed to resume unrestricted activity for 4 weeks at the end of which the knee range of motion was measured with standardized torques. The mean flexion contracture was higher in the immobilized group (51.9° ± 2.8°) than in the sham-operated group (18.9° ± 2.1°). Eighty-eight percent of the contractures remained in the immobilized group after dividing skin and muscle, suggesting an important contribution of the posterior knee capsule in limiting knee mobility. Based on our preliminary study the range of motion of rat knees immobilized for 8 weeks remained substantially reduced after a 4-week period of unassisted remobilization. PMID:18299947

Markerless motion capture can provide reliable 3D gait kinematics in the sagittal and frontal plane

DEFF Research Database (Denmark)

Sandau, Martin; Koblauch, Henrik; Moeslund, Thomas B.

2014-01-01

Estimating 3D joint rotations in the lower extremities accurately and reliably remains unresolved in markerless motion capture, despite extensive studies in the past decades. The main problems have been ascribed to the limited accuracy of the 3D reconstructions. Accordingly, the purpose of the pr......Estimating 3D joint rotations in the lower extremities accurately and reliably remains unresolved in markerless motion capture, despite extensive studies in the past decades. The main problems have been ascribed to the limited accuracy of the 3D reconstructions. Accordingly, the purpose...... subjects in whom hip, knee and ankle joint were analysed. Flexion/extension angles as well as hip abduction/adduction closely resembled those obtained from the marker based system. However, the internal/external rotations, knee abduction/adduction and ankle inversion/eversion were less reliable....

Anatomical kinematic constraints: consequences on muscular forces and joint reactions

OpenAIRE

MOISSENET, F; CHEZE, L; DUMAS, R

2011-01-01

This paper presents a method to determine musculo-tendon forces and joint reactions during gait, using a 3D right leg model with 5 DoFs: spherical joint at the hip and parallel mechanisms at both knee and ankle. A typical set of natural coordinates is used to obtain the dynamic equations. First, using a global optimization method, "anatomical" kinematic constraints (i.e., parallel mechanisms) are applied on the kinematics obtained from motion capture data. Consistent derivatives are computed ...

Biomechanics Analysis of Combat Sport (Silat) By Using Motion Capture System

Science.gov (United States)

Zulhilmi Kaharuddin, Muhammad; Badriah Khairu Razak, Siti; Ikram Kushairi, Muhammad; Syawal Abd. Rahman, Mohamed; An, Wee Chang; Ngali, Z.; Siswanto, W. A.; Salleh, S. M.; Yusup, E. M.

2017-01-01

‘Silat’ is a Malay traditional martial art that is practiced in both amateur and in professional levels. The intensity of the motion spurs the scientific research in biomechanics. The main purpose of this abstract is to present the biomechanics method used in the study of ‘silat’. By using the 3D Depth Camera motion capture system, two subjects are to perform ‘Jurus Satu’ in three repetitions each. One subject is set as the benchmark for the research. The videos are captured and its data is processed using the 3D Depth Camera server system in the form of 16 3D body joint coordinates which then will be transformed into displacement, velocity and acceleration components by using Microsoft excel for data calculation and Matlab software for simulation of the body. The translated data obtained serves as an input to differentiate both subjects’ execution of the ‘Jurus Satu’. Nine primary movements with the addition of five secondary movements are observed visually frame by frame from the simulation obtained to get the exact frame that the movement takes place. Further analysis involves the differentiation of both subjects’ execution by referring to the average mean and standard deviation of joints for each parameter stated. The findings provide useful data for joints kinematic parameters as well as to improve the execution of ‘Jurus Satu’ and to exhibit the process of learning a movement that is relatively unknown by the use of a motion capture system.

Inter-slice motion correction using spatiotemporal interpolation for functional magnetic resonance imaging of the moving fetus

OpenAIRE

Limperopoulos, Catherine; You, Wonsang

2017-01-01

Fetal motion continues to be one of the major artifacts in in-utero functional MRI; interestingly few methods have been developed to address fetal motion correction. In this study, we propose a robust method for motion correction in fetal fMRI by which both inter-slice and inter-volume motion artifacts are jointly corrected. To accomplish this, an original volume is temporally split into odd and even slices, and then voxel intensities are spatially and temporally interpolated in the process o...

In vivo recruitment patterns in the anterior oblique and dorsoradial ligaments of the first carpometacarpal joint

Science.gov (United States)

Halilaj, Eni; Rainbow, Michael J.; Moore, Douglas C.; Laidlaw, David H.; Weiss, Arnold-Peter C.; Ladd, Amy L.; Crisco, Joseph J.

2015-01-01

The anterior oblique ligament (AOL) and the dorsoradial ligament (DRL) are both regarded as mechanical stabilizers of the thumb carpometacarpal (CMC) joint, which in older women is often affected by osteoarthritis. Inferences on the potential relationship of these ligaments to joint pathomechanics are based on clinical experience and studies of cadaveric tissue, but their function has been studied sparsely in vivo. The purpose of this study was to gain insight into the functions of the AOL and DRL using in vivo joint kinematic data. The thumbs of 44 healthy subjects were imaged with a clinical computed tomography scanner in functional-task and thumb range-of-motion positions. The origins and insertion sites of the AOL and the DRL were identified on the 3D bone models and each ligament was modeled as a set of three fibers whose lengths were the minimum distances between insertion sites. Ligament recruitment, which represented ligament length as a percentage of the maximum length across the scanned positions, was computed for each position and related to joint posture. Mean AOL recruitment was lower than 91% across the CMC range of motion, whereas mean DRL recruitment was generally higher than 91% in abduction and flexion. Under the assumption that ligaments do not strain by more than 10% physiologically, our findings of mean ligament recruitments across the CMC range of motion indicate that the AOL is likely slack during most physiological positions, whereas the DRL may be taut and therefore support the joint in positions of CMC joint abduction and flexion. PMID:25964211

Interpersonal movement coordination in jointly moving a rocking board

NARCIS (Netherlands)

Bosga, J.; Meulenbroek, R.G.J.; Cuijpers, R.H.

2010-01-01

In this study, we investigate how two persons (dyads) coordinate their movements when performing cyclical motion patterns on a rocking board. In keeping with the Leading Joint Hypothesis (Dounskaia, 2005), the movement dynamics of the collaborating participants were expected to display features of a

Magnetic resonance study on the anatomical relationship between the posterior proximal region of the tibia and the popliteal artery ☆

Directory of Open Access Journals (Sweden)

Rogério Franco de Araujo Goes

2015-08-01

Full Text Available ABSTRACTOBJECTIVE: To analyze and describe the distance from the popliteal artery to three specific areas of the proximal region of the tibia, with the knee extended, by means of magnetic resonance. METHODS: Images of 100 knees of patients who underwent magnetic resonance examinations were analyzed. The location of the popliteal artery was measured in three different areas of the posterior proximal region of the tibia. The first measurement was made at the level of the knee joint (tibial plateau. The second was 9 mm distally to the tibial plateau. The third was at the level of the anterior tuberosity of the tibia (ATT. RESULTS: The distances between the popliteal artery and the tibial plateau and ATT region were significantly greater in males than in females. The distances between the popliteal artery and the regions 9 mm distally to the tibial plateau and the ATT were significantly greater in the age group over 36 years than in the group ≤36 years. CONCLUSION: Knowledge of the anatomical position of the popliteal artery, as demonstrated through magnetic resonance studies, is of great relevance in planning surgical procedures that involve the knee joint. In this manner, devastating iatrogenic injuries can be avoided, particularly in regions that are proximal to the tibial plateau and in young patients.

Pneumatic Multi-Pocket Elastomer Actuators for Metacarpophalangeal Joint Flexion and Abduction-Adduction

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Tapio Veli Juhani Tarvainen

2017-09-01

Full Text Available During recent years, interest has been rising towards developing fluidic fiber-reinforced elastomer actuators for wearable soft robotics used in hand rehabilitation and power-assist. However, they do not enable finger abduction-adduction, which plays an important role in activities of daily living, when grasping larger objects. Furthermore, the developed gloves often do not have separate control of joints, which is important for doing various common rehabilitation motions. The main obstacle for the development of a fully-assisting glove is moving a joint with multiple degrees of freedom. If the functions are built into the same structure, they are naturally coupled and affect each other, which makes them more difficult to design and complex to control than a simple flexion-extension actuator. In this study, we explored the key design elements and fabrication of pneumatic multi-pocket elastomer actuators for a soft rehabilitation glove. The goal was to gain more control over the metacarpophalangeal joint’s response by increasing the degree of actuation. Three main functional designs were tested for achieving both flexion and abduction-adduction. Five prototypes, with four different actuator geometries and four different reinforcement types, were designed and fabricated. They were evaluated by recording their free motion with motion capture and measuring their torque output using a dummy finger. Results showed the strengths and weaknesses of each design in separating the control of the two functions. We discuss the different improvements that are needed in order to make each design plausible for developing an actuator that meets the requirements for full assist of the hand’s motions. In conclusion, we show that it is possible to produce multi-pocket actuators for assisting MCP joint motion in both flexion and abduction-adduction, although coupling between the separate functions is still problematic and should be considered further.

Joint angles of the ankle, knee, and hip and loading conditions during split squats.

Science.gov (United States)

Schütz, Pascal; List, Renate; Zemp, Roland; Schellenberg, Florian; Taylor, William R; Lorenzetti, Silvio

2014-06-01

The aim of this study was to quantify how step length and the front tibia angle influence joint angles and loading conditions during the split squat exercise. Eleven subjects performed split squats with an additional load of 25% body weight applied using a barbell. Each subject's movements were recorded using a motion capture system, and the ground reaction force was measured under each foot. The joint angles and loading conditions were calculated using a cluster-based kinematic approach and inverse dynamics modeling respectively. Increases in the tibia angle resulted in a smaller range of motion (ROM) of the front knee and a larger ROM of the rear knee and hip. The external flexion moment in the front knee/hip and the external extension moment in the rear hip decreased as the tibia angle increased. The flexion moment in the rear knee increased as the tibia angle increased. The load distribution between the legs changed squat execution was varied. Our results describing the changes in joint angles and the resulting differences in the moments of the knee and hip will allow coaches and therapists to adapt the split squat exercise to the individual motion and load demands of athletes.

Evaluation of a direct motion estimation/correction method in respiratory-gated PET/MRI with motion-adjusted attenuation.

Science.gov (United States)

Bousse, Alexandre; Manber, Richard; Holman, Beverley F; Atkinson, David; Arridge, Simon; Ourselin, Sébastien; Hutton, Brian F; Thielemans, Kris

2017-06-01

Respiratory motion compensation in PET/CT and PET/MRI is essential as motion is a source of image degradation (motion blur, attenuation artifacts). In previous work, we developed a direct method for joint image reconstruction/motion estimation (JRM) for attenuation-corrected (AC) respiratory-gated PET, which uses a single attenuation-map (μ-map). This approach was successfully implemented for respiratory-gated PET/CT, but since it relied on an accurate μ-map for motion estimation, the question of its applicability in PET/MRI is open. The purpose of this work is to investigate the feasibility of JRM in PET/MRI and to assess the robustness of the motion estimation when a degraded μ-map is used. We performed a series of JRM reconstructions from simulated PET data using a range of simulated Dixon MRI sequence derived μ-maps with wrong attenuation values in the lungs, from -100% (no attenuation) to +100% (double attenuation), as well as truncated arms. We compared the estimated motions with the one obtained from JRM in ideal conditions (no noise, true μ-map as an input). We also applied JRM on 4 patient datasets of the chest, 3 of them containing hot lesions. Patient list-mode data were gated using a principal component analysis method. We compared SUV max values of the JRM reconstructed activity images and non motion-corrected images. We also assessed the estimated motion fields by comparing the deformed JRM-reconstructed activity with individually non-AC reconstructed gates. Experiments on simulated data showed that JRM-motion estimation is robust to μ-map degradation in the sense that it produces motion fields similar to the ones obtained when using the true μ-map, regardless of the attenuation errors in the lungs (PET/MRI clinical datasets. It provides a potential alternative to existing methods where the motion fields are pre-estimated from separate MRI measurements. © 2017 University College London (UCL). Medical Physics published by Wiley Periodicals, Inc

Joint hypermobility syndrome and related pain

Directory of Open Access Journals (Sweden)

Nilay Sahin

2016-06-01

Full Text Available Hypermobility is defined as an abnormally increased range of motion of a joint resulting from the excessive laxity of the soft tissues. This paper is focused on this commonly forgotten cause of several morbidities. The etiology of hypermobility is not very well known. One decade ago, joint hypermobility syndrome was considered as a benign condition, but now it is recognized as a significant contributor to chronic musculoskeletal pain, besides impacting on other organs. Patients with joint hypermobility syndrome often have diffuse, chronic complaints that are inconsistent with the musculoskeletal system. Chronic pain may cause loss of proprioception and so increased sensitivity to microtrauma, premature osteoarthritis de- velopment, soft tissue problems, psychosocial disorders, and neurophysiological deficiencies. Osteoarthritis, pes planus, mechanical low back pain, and soft tissue rheumatisms are frequent musculoskeletal findings as well as subluxations, thoracic outlet syndrome, rectal and uterine prolapses, hernias, and stress incontinence. Joint hypermobility syndrome's treatment is not easy, and nonsteroidal anti-inflammatory drugs are not usually effective or adequate. Proprioceptive and strengthening exercises have been reported to have supportive and therapeutic effects, but we have limited data on this issue. Joint hypermobility syndrome must be accepted as a multisystem connective tissue disorder rather than just joint laxities. As a result; clinicians must be aware of complexities of connective tissue disorders and comorbidities. [Arch Clin Exp Surg 2016; 5(2.000: 105-112

A survey of formal methods for determining functional joint axes.

Science.gov (United States)

Ehrig, Rainald M; Taylor, William R; Duda, Georg N; Heller, Markus O

2007-01-01

Axes of rotation e.g. at the knee, are often generated from clinical gait analysis data to be used in the assessment of kinematic abnormalities, the diagnosis of disease, or the ongoing monitoring of a patient's condition. They are additionally used in musculoskeletal models to aid in the description of joint and segment kinematics for patient specific analyses. Currently available methods to describe joint axes from segment marker positions share the problem that when one segment is transformed into the coordinate system of another, artefacts associated with motion of the markers relative to the bone can become magnified. In an attempt to address this problem, a symmetrical axis of rotation approach (SARA) is presented here to determine a unique axis of rotation that can consider the movement of two dynamic body segments simultaneously, and then compared its performance in a survey against a number of previously proposed techniques. Using a generated virtual joint, with superimposed marker error conditions to represent skin movement artefacts, fitting methods (geometric axis fit, cylinder axis fit, algebraic axis fit) and transformation techniques (axis transformation technique, mean helical axis, Schwartz approach) were classified and compared with the SARA. Nearly all approaches were able to estimate the axis of rotation to within an RMS error of 0.1cm at large ranges of motion (90 degrees ). Although the geometric axis fit produced the least RMS error of approximately 1.2 cm at lower ranges of motion (5 degrees ) with a stationary axis, the SARA and Axis Transformation Technique outperformed all other approaches under the most demanding marker artefact conditions for all ranges of motion. The cylinder and algebraic axis fit approaches were unable to compute competitive AoR estimates. Whilst these initial results using the SARA are promising and are fast enough to be determined "on-line", the technique must now be proven in a clinical environment.

Lower limb joint moment during walking in water.

Science.gov (United States)

Miyoshi, Tasuku; Shirota, Takashi; Yamamoto, Shin-Ichiro; Nakazawa, Kimitaka; Akai, Masami

2003-11-04

Walking in water is a widely used rehabilitation method for patients with orthopedic disorders or arthritis, based on the belief that the reduction of weight in water makes it a safer medium and prevents secondary injuries of the lower-limb joints. To our knowledge, however, no experimental data on lower-limb joint moment during walking in water is available. The aim of this study was to quantify the joint moments of the ankle, knee, and hip during walking in water in comparison with those on land. Eight healthy volunteers walked on land and in water at a speed comfortable for them. A video-motion analysis system and waterproof force platform were used to obtain kinematic data and to calculate the joint moments. The hip joint moment was shown to be an extension moment almost throughout the stance phase during walking in water, while it changed from an extension- to flexion-direction during walking on land. The knee joint moment had two extension peaks during walking on land, whereas it had only one extension peak, a late one, during walking in water. The ankle joint moment during walking in water was considerably reduced but in the same direction, plantarflexion, as that during walking on land. The joint moments of the hip, knee, and ankle were not merely reduced during walking in water; rather, inter-joint coordination was totally changed.

Comparison of Joint Loading in Badminton Lunging between Professional and Amateur Badminton Players

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Lin Fu

2017-01-01

Full Text Available The knee and ankle are the two most injured joints associated with the sport of badminton. This study evaluates biomechanical factors between professional and amateur badminton players using an injury mechanism model. The aim of this study was to investigate the kinematic motion and kinetic loading differences of the right knee and ankle while performing a maximal right lunge. Amateur players exhibited greater ankle range of motion (p<0.05, r=0.89 and inversion joint moment (p<0.05, r=0.54 in the frontal plane as well as greater internal joint rotation moment (p<0.05, r=0.28 in the horizontal plane. In contrast, professional badminton players presented a greater knee joint moment in the sagittal (p<0.05, r=0.59 and frontal (p<0.05, r=0.37 planes, which may be associated with increased knee ligamentous injury risk. To avoid injury, the players need to forcefully extend the knee with internal rotation, strengthen the muscles around the ankle ligament, and maximise joint coordination during training. The injuries recorded and the forces responsible for the injuries seem to have developed during training activity. Training programmes and injury prevention strategies for badminton players should account for these findings to reduce potential injury to the ankle and knee.

Joint multifractal analysis based on wavelet leaders

Science.gov (United States)

Jiang, Zhi-Qiang; Yang, Yan-Hong; Wang, Gang-Jin; Zhou, Wei-Xing

2017-12-01

Mutually interacting components form complex systems and these components usually have long-range cross-correlated outputs. Using wavelet leaders, we propose a method for characterizing the joint multifractal nature of these long-range cross correlations; we call this method joint multifractal analysis based on wavelet leaders (MF-X-WL). We test the validity of the MF-X-WL method by performing extensive numerical experiments on dual binomial measures with multifractal cross correlations and bivariate fractional Brownian motions (bFBMs) with monofractal cross correlations. Both experiments indicate that MF-X-WL is capable of detecting cross correlations in synthetic data with acceptable estimating errors. We also apply the MF-X-WL method to pairs of series from financial markets (returns and volatilities) and online worlds (online numbers of different genders and different societies) and determine intriguing joint multifractal behavior.

Intra-articular elastofibroma of the shoulder joint

International Nuclear Information System (INIS)

Bae, Sang-Jin; Shin, Myung Jin; Kim, Sung Moon; Cho, Kyung-Ja

2002-01-01

A 19-year-old man presented with an elastofibroma in his left shoulder joint. The patient had had limitation of motion in his left arm for 3 years, especially when rotating internally. Radiography of his left shoulder showed bone erosion in the neck of the humerus. On MR imaging, a soft tissue mass was noted in the shoulder joint eroding bone. The mass showed similar signal intensity to that of surrounding muscles on T1- and T2-weighted images. At surgery, a soft, encapsulated mass was found attached to the subscapularis muscle. It was pathologically confirmed as an elastofibroma. This unusual manifestation of an elastofibroma is discussed. (orig.)

Proximity credentials: A survey

International Nuclear Information System (INIS)

Wright, L.J.

1987-04-01

Credentials as a means of identifying individuals have traditionally been a photo badge and more recently, the coded credential. Another type of badge, the proximity credential, is making inroads in the personnel identification field. This badge can be read from a distance instead of being veiewed by a guard or inserted into a reading device. This report reviews proximity credentials, identifies the companies marketing or developing proximity credentials, and describes their respective credentials. 3 tabs

Principles of human joint replacement design and clinical application

CERN Document Server

Buechel, Frederick F

2015-01-01

This book is written for the users and designers of joint replacements. In its second extended edition it conveys to the reader the knowledge accumulated by the authors during their forty year effort on the development of replacement devices for the lower limb for the purpose of aiding the reader in their design and evaluation of joint replacement devices. The early chapters describe the engineering, scientific and medical principles needed for replacement joint evaluation. One must understand the nature and performance of the materials involved and their characteristics in vivo, i.e. the response of the body to implant materials. It is also essential to understand the response of the implants to applied loading and motion, particularly in the hostile physiological environment. A chapter describes the design methodology now required for joint replacement in the USA and EU countries. The remaining chapters provide a history of joint replacement, an evaluation of earlier and current devices and sample case hist...

Modelling of subject specific based segmental dynamics of knee joint

Science.gov (United States)

Nasir, N. H. M.; Ibrahim, B. S. K. K.; Huq, M. S.; Ahmad, M. K. I.

2017-09-01

This study determines segmental dynamics parameters based on subject specific method. Five hemiplegic patients participated in the study, two men and three women. Their ages ranged from 50 to 60 years, weights from 60 to 70 kg and heights from 145 to 170 cm. Sample group included patients with different side of stroke. The parameters of the segmental dynamics resembling the knee joint functions measured via measurement of Winter and its model generated via the employment Kane's equation of motion. Inertial parameters in the form of the anthropometry can be identified and measured by employing Standard Human Dimension on the subjects who are in hemiplegia condition. The inertial parameters are the location of centre of mass (COM) at the length of the limb segment, inertia moment around the COM and masses of shank and foot to generate accurate motion equations. This investigation has also managed to dig out a few advantages of employing the table of anthropometry in movement biomechanics of Winter's and Kane's equation of motion. A general procedure is presented to yield accurate measurement of estimation for the inertial parameters for the joint of the knee of certain subjects with stroke history.

Arthroscopic sternoclavicular joint resection arthroplasty: a technical note and illustrated case report.

Science.gov (United States)

Warth, Ryan J; Lee, Jared T; Campbell, Kevin J; Millett, Peter J

2014-02-01

Open resection arthroplasty of the sternoclavicular (SC) joint has historically provided good long-term results in patients with symptomatic osteoarthritis of the SC joint. However, the procedure is rarely performed because of the risk of injury to vital mediastinal structures and concern regarding postoperative joint instability. Arthroscopic decompression of the SC joint has therefore emerged as a potential treatment option because of many recognized advantages including minimal tissue dissection, maintenance of joint stability, avoidance of posterior SC joint dissection, expeditious recovery, and improved cosmesis. There are, however, safety concerns given the proximity of neurovascular structures. In this article we demonstrate a technique for arthroscopic SC joint resection arthroplasty in a 26-year-old active man with bilateral, painful, idiopathic degenerative SC joint osteoarthritis. This case also highlights the pearls and pitfalls of arthroscopic resection arthroplasty for the SC joint. There were no perioperative complications. Four months postoperatively, the patient had returned to full activities, including weightlifting, without pain or evidence of SC joint instability. One year postoperatively, the patient showed substantial improvements in the American Shoulder and Elbow Surgeons score; Single Assessment Numeric Evaluation score; Quick Disabilities of the Arm, Shoulder and Hand score; and Short Form 12 Physical Component Summary score over preoperative baseline values.

An improved method for calculating self-motion coordinates for redundant manipulators

International Nuclear Information System (INIS)

Reister, D.B.

1997-04-01

For a redundant manipulator, the objective of redundancy resolution is to follow a specified path in Cartesian space and simultaneously perform another task (for example, maximize an objective function or avoid obstacles) at every point along the path. The conventional methods have several drawbacks: a new function must be defined for each task, the extended Jacobian can be singular, closed cycles in Cartesian space may not yield closed cycles in joint space, and the objective is point-wise redundancy resolution (to determine a single point in joint space for each point in Cartesian space). The author divides the redundancy resolution problem into two parts: (1) calculate self-motion coordinates for all possible positions of a manipulator at each point along a Cartesian path and (2) determination of optimal self-motion coordinates that maximize an objective function along the path. This paper will discuss the first part of the problem. The path-wise approach overcomes all of the drawbacks of conventional redundancy resolution methods: no need to define a new function for each task, extended Jacobian cannot be singular, and closed cycles in extended Cartesian space will yield closed cycles in joint space

Medial collateral ligament tear entrapped within a proximal tibial physeal separation: imaging findings and operative reduction

Energy Technology Data Exchange (ETDEWEB)

McAnally, James L.; Eberhardt, Steven C.; Mlady, Gary W. [University of New Mexico, Department of Radiology, Albuquerque, NM (United States); Fitzpatrick, Jennifer; Bosch, Patrick [University of New Mexico, Department of Orthopaedics and Rehabilitation, Albuquerque, NM (United States)

2008-10-15

Entrapped soft tissues such as periosteum and tendons have been described within joints and physeal fractures in the literature and frequently result in irreducible fractures and posttraumatic growth disturbances. We believe this case represents a novel presentation of acute, preoperative, magnetic resonance (MR) imaging diagnosis of a torn medial collateral ligament entrapped within a proximal tibial physeal separation. This case is presented with MR imaging and operative correlation of the findings. (orig.)

Medial collateral ligament tear entrapped within a proximal tibial physeal separation: imaging findings and operative reduction

International Nuclear Information System (INIS)

McAnally, James L.; Eberhardt, Steven C.; Mlady, Gary W.; Fitzpatrick, Jennifer; Bosch, Patrick

2008-01-01

Entrapped soft tissues such as periosteum and tendons have been described within joints and physeal fractures in the literature and frequently result in irreducible fractures and posttraumatic growth disturbances. We believe this case represents a novel presentation of acute, preoperative, magnetic resonance (MR) imaging diagnosis of a torn medial collateral ligament entrapped within a proximal tibial physeal separation. This case is presented with MR imaging and operative correlation of the findings. (orig.)

Flexor Hallucis Longus tendon rupture in RA-patients is associated with MTP 1 damage and pes planus

Directory of Open Access Journals (Sweden)

Buurke Jaap J

2007-11-01

Full Text Available Abstract Background To assess the prevalence of and relation between rupture or tenosynovitis of the Flexor Hallucis Longus (FHL tendon and range of motion, deformities and joint damage of the forefoot in RA patients with foot complaints. Methods Thirty RA patients with painful feet were analysed, their feet were examined clinically for the presence of pes planus and range of motion (ROM, radiographs were scored looking for the presence of forefoot damage, and ultrasound examination was performed, examining the presence of tenosyovitis or rupture of the FHL at the level of the medial malleolus. The correlation between the presence or absence of the FHL and ROM, forefoot damage and pes planus was calculated. Results In 11/60(18% of the feet, a rupture of the FHL was found. This was associated with a limited motion of the MTP1-joint, measured on the JAM (χ2 = 10.4, p = 0.034, a higher prevalence of pes planus (χ2 = 5.77, p = 0.016 and a higher prevalence of erosions proximal at the MTP-1 joint (χ2 = 12.3, p = 0.016, and joint space narrowing of the MTP1 joint (χ2 = 12.7, p = 0.013. Conclusion Rupture of the flexor hallucis longus tendon in RA-patients is associated with limited range of hallux motion, more erosions and joint space narrowing of the MTP-1-joint, as well as with pes planus.

Osteochondral lesions in distal tarsal joints of Icelandic horses reveal strong associations between hyaline and calcified cartilage abnormalities.

Science.gov (United States)

Ley, C J; Ekman, S; Hansson, K; Björnsdóttir, S; Boyde, A

2014-03-25

Osteochondral lesions in the joints of the distal tarsal region of young Icelandic horses provide a natural model for the early stages of osteoarthritis (OA) in low-motion joints. We describe and characterise mineralised and non-mineralised osteochondral lesions in left distal tarsal region joint specimens from twenty-two 30 ±1 month-old Icelandic horses. Combinations of confocal scanning light microscopy, backscattered electron scanning electron microscopy (including, importantly, iodine staining) and three-dimensional microcomputed tomography were used on specimens obtained with guidance from clinical imaging. Lesion-types were described and classified into groups according to morphological features. Their locations in the hyaline articular cartilage (HAC), articular calcified cartilage (ACC), subchondral bone (SCB) and the joint margin tissues were identified and their frequency in the joints recorded. Associations and correlations between lesion-types were investigated for centrodistal joints only. In centrodistal joints the lesion-types HAC chondrocyte loss, HAC fibrillation, HAC central chondrocyte clusters, ACC arrest and ACC advance had significant associations and strong correlations. These lesion-types had moderate to high frequency in centrodistal joints but low frequencies in tarsometatarsal and talocalcaneal-centroquartal joints. Joint margin lesion-types had no significant associations with other lesion-types in the centrodistal joints but high frequency in both the centrodistal and tarsometatarsal joints. The frequency of SCB lesion-types in all joints was low. Hypermineralised infill phase lesion-types were detected. Our results emphasise close associations between HAC and ACC lesions in equine centrodistal joints and the importance of ACC lesions in the development of OA in low-motion compression-loaded equine joints.

Learning by Demonstration for Motion Planning of Upper-Limb Exoskeletons

Science.gov (United States)

Lauretti, Clemente; Cordella, Francesca; Ciancio, Anna Lisa; Trigili, Emilio; Catalan, Jose Maria; Badesa, Francisco Javier; Crea, Simona; Pagliara, Silvio Marcello; Sterzi, Silvia; Vitiello, Nicola; Garcia Aracil, Nicolas; Zollo, Loredana

2018-01-01

The reference joint position of upper-limb exoskeletons is typically obtained by means of Cartesian motion planners and inverse kinematics algorithms with the inverse Jacobian; this approach allows exploiting the available Degrees of Freedom (i.e. DoFs) of the robot kinematic chain to achieve the desired end-effector pose; however, if used to operate non-redundant exoskeletons, it does not ensure that anthropomorphic criteria are satisfied in the whole human-robot workspace. This paper proposes a motion planning system, based on Learning by Demonstration, for upper-limb exoskeletons that allow successfully assisting patients during Activities of Daily Living (ADLs) in unstructured environment, while ensuring that anthropomorphic criteria are satisfied in the whole human-robot workspace. The motion planning system combines Learning by Demonstration with the computation of Dynamic Motion Primitives and machine learning techniques to construct task- and patient-specific joint trajectories based on the learnt trajectories. System validation was carried out in simulation and in a real setting with a 4-DoF upper-limb exoskeleton, a 5-DoF wrist-hand exoskeleton and four patients with Limb Girdle Muscular Dystrophy. Validation was addressed to (i) compare the performance of the proposed motion planning with traditional methods; (ii) assess the generalization capabilities of the proposed method with respect to the environment variability. Three ADLs were chosen to validate the system: drinking, pouring and lifting a light sphere. The achieved results showed a 100% success rate in the task fulfillment, with a high level of generalization with respect to the environment variability. Moreover, an anthropomorphic configuration of the exoskeleton is always ensured. PMID:29527161

Learning by Demonstration for Motion Planning of Upper-Limb Exoskeletons

Directory of Open Access Journals (Sweden)

Clemente Lauretti

2018-02-01

Full Text Available The reference joint position of upper-limb exoskeletons is typically obtained by means of Cartesian motion planners and inverse kinematics algorithms with the inverse Jacobian; this approach allows exploiting the available Degrees of Freedom (i.e. DoFs of the robot kinematic chain to achieve the desired end-effector pose; however, if used to operate non-redundant exoskeletons, it does not ensure that anthropomorphic criteria are satisfied in the whole human-robot workspace. This paper proposes a motion planning system, based on Learning by Demonstration, for upper-limb exoskeletons that allow successfully assisting patients during Activities of Daily Living (ADLs in unstructured environment, while ensuring that anthropomorphic criteria are satisfied in the whole human-robot workspace. The motion planning system combines Learning by Demonstration with the computation of Dynamic Motion Primitives and machine learning techniques to construct task- and patient-specific joint trajectories based on the learnt trajectories. System validation was carried out in simulation and in a real setting with a 4-DoF upper-limb exoskeleton, a 5-DoF wrist-hand exoskeleton and four patients with Limb Girdle Muscular Dystrophy. Validation was addressed to (i compare the performance of the proposed motion planning with traditional methods; (ii assess the generalization capabilities of the proposed method with respect to the environment variability. Three ADLs were chosen to validate the system: drinking, pouring and lifting a light sphere. The achieved results showed a 100% success rate in the task fulfillment, with a high level of generalization with respect to the environment variability. Moreover, an anthropomorphic configuration of the exoskeleton is always ensured.

[Advances on biomechanics and kinematics of sprain of ankle joint].

Science.gov (United States)

Zhao, Yong; Wang, Gang

2015-04-01

Ankle sprains are orthopedic clinical common disease, accounting for joint ligament sprain of the first place. If treatment is not timely or appropriate, the joint pain and instability maybe develop, and even bone arthritis maybe develop. The mechanism of injury of ankle joint, anatomical basis has been fully study at present, and the diagnostic problem is very clear. Along with the development of science and technology, biological modeling and three-dimensional finite element, three-dimensional motion capture system,digital technology study, electromyographic signal study were used for the basic research of sprain of ankle. Biomechanical and kinematic study of ankle sprain has received adequate attention, combined with the mechanism research of ankle sprain,and to explore the the biomechanics and kinematics research progress of the sprain of ankle joint.

Forelimb muscle and joint actions in Archosauria: insights from Crocodylus johnstoni (Pseudosuchia and Mussaurus patagonicus (Sauropodomorpha

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Alejandro Otero

2017-11-01

Full Text Available Many of the major locomotor transitions during the evolution of Archosauria, the lineage including crocodiles and birds as well as extinct Dinosauria, were shifts from quadrupedalism to bipedalism (and vice versa. Those occurred within a continuum between more sprawling and erect modes of locomotion and involved drastic changes of limb anatomy and function in several lineages, including sauropodomorph dinosaurs. We present biomechanical computer models of two locomotor extremes within Archosauria in an analysis of joint ranges of motion and the moment arms of the major forelimb muscles in order to quantify biomechanical differences between more sprawling, pseudosuchian (represented the crocodile Crocodylus johnstoni and more erect, dinosaurian (represented by the sauropodomorph Mussaurus patagonicus modes of forelimb function. We compare these two locomotor extremes in terms of the reconstructed musculoskeletal anatomy, ranges of motion of the forelimb joints and the moment arm patterns of muscles across those ranges of joint motion. We reconstructed the three-dimensional paths of 30 muscles acting around the shoulder, elbow and wrist joints. We explicitly evaluate how forelimb joint mobility and muscle actions may have changed with postural and anatomical alterations from basal archosaurs to early sauropodomorphs. We thus evaluate in which ways forelimb posture was correlated with muscle leverage, and how such differences fit into a broader evolutionary context (i.e. transition from sprawling quadrupedalism to erect bipedalism and then shifting to graviportal quadrupedalism. Our analysis reveals major differences of muscle actions between the more sprawling and erect models at the shoulder joint. These differences are related not only to the articular surfaces but also to the orientation of the scapula, in which extension/flexion movements in Crocodylus (e.g. protraction of the humerus correspond to elevation/depression in Mussaurus. Muscle

Motion Artifact in the MR imaging of temporomandibular disorders

International Nuclear Information System (INIS)

Tamamura, Kiyoharu; Miyajima, Hisashi; Nihei, Yoshinobu; Nemoto, Ryuichi; Ohno, Tomoya

1997-01-01

Recently, magnetic resonance imaging (MRI) is indispensable for the diagnosis of temporomandibular disorders (TMD). Motion Artifacts of MRI occur more frequently than in other conventional methods, because it takes a long time to obtain the images. This paper reported on Motion Artifacts on MRI. MRI studies of 232 temporomandibular joints were performed in 116 patients with TMD by using a 0.5-T magnetic resonance (MR) scanner, with spin echo sequence: protondensity-weighted. And we took MRI slices at opening phase and closing phase. So 232 slices were gathered and we evaluated clinically the incidence of Motion Artifacts, that is to say, double and multiple images and other factors. The 103 slices in 56 patients showed Motion Artifacts. There is no significant difference between sexes. By age group, those in their teens were most frequent, followed by those in their fifties, forties, thirties and twenties. Also the same results were obtained for double image and multiple image. Incidence of Motion Artifact was most frequent at the opening phase. There is no significant difference between double and multiple image. (author)

Effects of joint alignment and type on mechanical properties of thermoplastic articulated ankle-foot orthosis.

Science.gov (United States)

Gao, Fan; Carlton, William; Kapp, Susan

2011-06-01

Articulated or hinged ankle-foot orthosis (AFO) allow more range of motion. However, quantitative investigation on articulated AFO is still sparse. The objective of the study was to quantitatively investigate effects of alignment and joint types on mechanical properties of the thermoplastic articulated AFO. Tamarack dorsiflexion assist flexure joints with three durometers (75, 85 and 95) and free motion joint were tested. The AFO joint was aligned with the center of the motor shaft (surrogate ankle joint), 10 mm superior, inferior, anterior and posterior with respect to the motor shaft center. The AFO was passively moved from 20° plantar flexion to 15° dorsiflexion at a speed of 10°/s using a motorized device. Mechanical properties including index of hysteresis, passive resistance torque and quasi-static stiffness (at neutral, 5°, 10° and 15° in plantar flexion) were quantified. Significant effects of joint types and joint alignment on the mechanical properties of an articulated thermoplastic AFO were revealed. Specifically, center alignment showed minimum resistance and stiffness while anterior and posterior alignment showed significantly higher resistance and stiffness. The dorsiflexion assist torques at neutral position ranged from 0.69 ± 0.09 to 1.88 ± 0.10 Nm. Anterior and posterior alignment should be avoided as much as possible. The current study suggested that anterior and posterior alignment be avoided as much as possible in clinical practice due to potential skin irritation and increase in stress around the ankle joint.

[Treatment of bacterial infection in the interphalangeal joints of the hand].

Science.gov (United States)

Vorderwinkler, K-P; Mühldorfer, M; Pillukat, T; van Schoonhoven, J

2011-07-01

Radical debridement of joint infection, prevention of further infection-related tissue destruction. Septic arthritis of interphalangeal joints in the thumb and fingers. Extensive soft tissue defects. Severe impairment of blood circulation, finger gangrene. Noncompliance for immobilization or for treatment with external fixator. Arthrotomy and irrigation with isotonic solution. Radical tissue debridement. Joint preservation possible only in the absence of infection-related macroscopic cartilage damage. Otherwise, resection of the articular surfaces and secondary arthrodesis. Insertion of antibiotic-coated devices. Temporary immobilization with external fixator. Inpatient postoperative treatment with 5-day intravenous administration of a second-generation cephalosporine (e.g., Cefuroxim®) followed by 7-10 days oral application. Adaptation of antibiotics according to antibiogram results. In joint-preserving procedures, radiographs and fixator removal after 4 weeks, active joint mobilization. If joint surfaces were resected, removal of fixator after 6 weeks; arthrodesis under 3-day intravenous broad-band antibiotic prophylaxis. Splint immobilization until consolidation (6-8 weeks). In 10 of 40 patients, the infected joint could be preserved. All infections healed. After an average duration of therapy of 6 (3-11) weeks, 4 individuals were free of complaints, and 6 patients had minor symptoms. Overall range of motion in the affected finger was reduced by 25-50° in 5 patients. All patients could return to work after 6.6 (4-11) weeks. A total of 30 patients were treated with joint resection and external fixator. After 5.6 (4-8) weeks, arthrodesis was performed, leading to consolidation in 29 patients. One patient underwent amputation after 4 months due to delayed gangrene. Treatment duration was 15.7 (7-25) weeks. Eight patients reported no complaints, 14 suffered mild symptoms, 5 had moderate, and 3 had severe symptoms in daily life. In 15 cases, range

Effects of Fatigue on Frontal Plane Knee Motion, Muscle Activity, and Ground Reaction Forces In Men and Women During Landing

OpenAIRE

Smith, Michael P.; Sizer, Phillip S.; James, C. Roger

2009-01-01

Women tear their Anterior Cruciate Ligament (ACL) 2-8 times more frequently than men. Frontal plane knee motion can produce a pathological load in the ACL. During a state of fatigue the muscles surrounding the knee joint may lose the ability to protect the joint during sudden deceleration while landing. The purpose of this study was to investigate the effects of fatigue and gender on frontal plane knee motion, EMG amplitudes, and GRF magnitudes during drop- jump landing. Pretest-posttest comp...

Quantification of respiration-induced esophageal tumor motion using fiducial markers and four-dimensional computed tomography.

Science.gov (United States)

Jin, Peng; Hulshof, Maarten C C M; de Jong, Rianne; van Hooft, Jeanin E; Bel, Arjan; Alderliesten, Tanja

2016-03-01

Respiration-induced tumor motion is an important geometrical uncertainty in esophageal cancer radiation therapy. The aim of this study was to quantify this motion using fiducial markers and four-dimensional computed tomography (4DCT). Twenty esophageal cancer patients underwent endoscopy-guided marker implantation in the tumor volume and 4DCT acquisition. The 4DCT data were sorted into 10 breathing phases and the end-of-inhalation phase was selected as reference. We quantified for each visible marker (n=60) the motion in each phase and derived the peak-to-peak motion magnitude throughout the breathing cycle. The motion was quantified and analyzed for four different regions and in three orthogonal directions. The median(interquartile range) of the peak-to-peak magnitudes of the respiration-induced marker motion (left-right/anterior-posterior/cranial-caudal) was 1.5(0.5)/1.6(0.5)/2.9(1.4) mm for the proximal esophagus (n=6), 1.5(1.4)/1.4(1.3)/3.7(2.6) mm for the middle esophagus (n=12), 2.6(1.3)/3.3(1.8)/5.4(2.9) mm for the distal esophagus (n=25), and 3.7(2.1)/5.3(1.8)/8.2(3.1) mm for the proximal stomach (n=17). The variations in the results between the three directions, four regions, and patients suggest the need of individualized region-dependent anisotropic internal margins. Therefore, we recommend using markers with 4DCT to patient-specifically adapt the internal target volume (ITV). Without 4DCT, 3DCTs at the end-of-inhalation and end-of-exhalation phases could be alternatively applied for ITV individualization. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

[Dislocation of the PIP-Joint - Treatment of a common (ball)sports injury].

Science.gov (United States)

Müller-Seubert, Wibke; Bührer, Gregor; Horch, Raymund E

2017-09-01

Background  Fractures or fracture dislocations of the proximal interphalangeal joint often occur during sports or accidents. Dislocations of the PIP-joint are the most common ligamentary injuries of the hand. As this kind of injury is so frequent, hand surgeons and other physicians should be aware of the correct treatment. Objectives  This paper summarises the most common injury patterns and the correct treatment of PIP-joint dislocations. Materials and Methods  This paper reviews the current literature and describes the standardised treatment of PIP-joint dislocations. Results  What is most important is that reposition is anatomically correct, and this should be controlled by X-ray examination. Depending on the instability and possible combination with other injuries (e. g. injury to the palmar plate), early functional physiotherapy of the joint or a short immobilisation period is indicated. Conclusions  Early functional treatment of the injured PIP-joint, initially using buddy taping, is important to restore PIP-joint movement and function. Depending on the injury, joint immobilisation using a K-wire may be indicated. Detailed informed consent is necessary to explain to the patient the severity of the injury and possible complications, such as chronic functional disorders or development of arthrosis. © Georg Thieme Verlag KG Stuttgart · New York.

Potential of optical spectral transmission measurements for joint inflammation measurements in rheumatoid arthritis patients

Science.gov (United States)

Meier, A. J. Louise; Rensen, Wouter H. J.; de Bokx, Pieter K.; de Nijs, Ron N. J.

2012-08-01

Frequent monitoring of rheumatoid arthritis (RA) patients enables timely treatment adjustments and improved outcomes. Currently this is not feasible due to a shortage of rheumatologists. An optical spectral transmission device is presented for objective assessment of joint inflammation in RA patients, while improving diagnostic accuracy and clinical workflow. A cross-sectional, nonrandomized observational study was performed with this device. In the study, 77 proximal interphalangeal (PIP) joints in 67 patients have been analyzed. Inflammation of these PIP joints was also assessed by a rheumatologist with a score varying from 1 (not inflamed) to 5 (severely inflamed). Out of 77 measurements, 27 were performed in moderate to strongly inflamed PIP joints. Comparison between the clinical assessment and an optical measurement showed a correlation coefficient r=0.63, p<0.001, 95% CI [0.47, 0.75], and a ROC curve (AUC=0.88) that shows a relative good specificity and sensitivity. Optical spectral transmission measurements in a single joint correlate with clinical assessment of joint inflammation, and therefore might be useful in monitoring joint inflammation in RA patients.

Evaluation of taper joints with combined fatigue and crevice corrosion testing: Comparison to human explanted modular prostheses

Energy Technology Data Exchange (ETDEWEB)

Reclaru, L., E-mail: lucien.reclaru@pxgroup.com [PX Group S.A., Dep R and D Corrosion and Biocompatibility Group, Bd. des Eplatures 42, CH-2304 La Chaux-de-Fonds (Switzerland); Brooks, R.A. [Orthopaedic Research, Addenbrooke' s Hospital, University of Cambridge, Box 180 Hills Road, CB2 0QQ Cambridge (United Kingdom); Zuberbühler, M. [Smith and Nephew Orthopaedics AG, Schachenalle 29, 5001 Aarau (Switzerland); Eschler, P.-Y.; Constantin, F. [PX Group S.A., Dep R and D Corrosion and Biocompatibility Group, Bd. des Eplatures 42, CH-2304 La Chaux-de-Fonds (Switzerland); Tomoaia, G. [University of Medicine and Pharmacy Iuliu Hateganu of Cluj-Napoca, Dept. of Orthopaedics and Traumatology, Cluj-Napoca (Romania)

2014-01-01

The requirement for revision surgery of total joint replacements is increasing and modular joint replacement implants have been developed to provide adjustable prosthetic revision systems with improved intra-operative flexibility. An electrochemical study of the corrosion resistance of the interface between the distal and proximal modules of a modular prosthesis was performed in combination with a cyclic fatigue test. The complexity resides in the existence of interfaces between the distal part, the proximal part, and the dynamometric screw. A new technique for evaluating the resistance to cyclic dynamic corrosion with crevice stimulation was used and the method is presented. In addition, two components of the proximal module of explanted Ti6Al4V and Ti6Al7Nb prostheses were investigated by optical and electron microscopy. Our results reveal that: The electrolyte penetrates into the interface between the distal and proximal modules during cyclic dynamic fatigue tests, the distal module undergoes cracking and corrosion was generated at the interface between the two models; The comparison of the explanted proximal parts with the similar prostheses evaluated following cyclic dynamic crevice corrosion testing showed that there were significant similarities indicating that this method is suitable for evaluating materials used in the fabrication of modular prostheses. - Highlights: • Electrochemical crevice corrosion testing combined with fatigue test conducted on Ti6Al7Nb and Ti6Al4V modular prostheses • Cations released from integral prostheses • Comparison of human explanted modular prostheses with the similar prostheses evaluated in cyclic dynamic crevice corrosion.

Workspace location influences joint coordination during reaching in post-stroke hemiparesis

Science.gov (United States)

Reisman, Darcy S.; Scholz, John P.

2006-01-01

The purpose of this study was to determine the influence of workspace location on joint coordination in persons with post-stroke hemiparesis when trunk motion was required to complete reaches beyond the arm’s functional reach length. Seven subjects with mild right hemiparesis following a stroke and seven age and gender matched control subjects participated. Joint motions and characteristics of hand and trunk movement were measured over multiple repetitions. The variance (across trials) of joint combinations was partitioned into two components at every point in the hand’s trajectory using the uncontrolled manifold approach; the first component is a measure of the extent to which equivalent joint combinations are used to control a given hand path, and reflects performance flexibility. The second component of joint variance reflects the use of non-equivalent joint combinations, which lead to hand path error. Compared to the control subjects, persons with hemiparesis demonstrated a significantly greater amount of non-equivalent joint variability related to control of the hand’s path and of the hand’s position relative to the trunk when reaching toward the hemiparetic side (ipsilaterally), but not when reaching to the less involved side. The relative timing of the hand and trunk was also altered when reaching ipsilaterally. The current findings support the idea that the previously proposed “arm compensatory synergy” may be deficient in subjects with hemiparesis. This deficiency may be due to one or a combination of factors: changes in central commands that are thought to set the gain of the arm compensatory synergy; a limited ability to combine shoulder abduction and elbow extension that limits the expression of an appropriately set arm compensatory synergy; or a reduction of the necessary degrees-of-freedom needed to adequately compensate for poor trunk control when reaching ipsilaterally. PMID:16328275

Occupation times distribution for Brownian motion on graphs

CERN Document Server

Desbois, J

2002-01-01

Considering a Brownian motion on a general graph, we study the joint law for the occupation times on all the bonds. In particular, we show that the Laplace transform of this distribution can be expressed as the ratio of two determinants. We give two formulations, with arc or vertex matrices, for this result and discuss a simple example. (letter to the editor)

Anatomical study of the articular branches innervated the hip and knee joint with reference to mechanism of referral pain in hip joint disease patients.

Science.gov (United States)

Sakamoto, Junya; Manabe, Yoshitaka; Oyamada, Joichi; Kataoka, Hideki; Nakano, Jiro; Saiki, Kazunobu; Okamoto, Keishi; Tsurumoto, Toshiyuki; Okita, Minoru

2018-03-25

Referred pain in the anterior knee joint is the most common symptom in hip disease patients. The development of referred pain is considered to be related to dichotomizing peripheral sensory fibers. However, no gross anatomical findings identify any dichotomizing fibers innervating both the hip and knee joints. We dissected the femoral and obturator nerves in human cadavers to investigate the distribution of the articular branches in the hip and knee joints. Fourteen embalmed left lower limbs from 14 Japanese adult cadavers (five from females, nine from males, average age 73.8 ± 14.1 years) were observed macroscopically. The articular branches of the femoral and obturator nerves were dissected at the anterior margin of the groin toward the thigh region. After dissections of the articular nerves of the hip joints, the femoral and obturator nerves were exposed from proximally to distally to identify the articular nerves of the knee joints. The branching pattern of the articular branches in the hip and knee joints was recorded. In six of 14 limbs (42.9%), the femoral nerve supplied articular branches to the anteromedial aspect of both the hip and knee joints. These articular branches were derived from the same bundle of femoral nerve. These gross anatomical findings suggested that dichotomizing peripheral sensory fibers innervate the hip and knee joints and these could relate to the referred pain confirmed in the anterior knee joints of patients with hip disease. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc. © 2018 Wiley Periodicals, Inc.

Compensatory motor control after stroke: an alternative joint strategy for object-dependent shaping of hand posture.

Science.gov (United States)

Raghavan, Preeti; Santello, Marco; Gordon, Andrew M; Krakauer, John W

2010-06-01

Efficient grasping requires planned and accurate coordination of finger movements to approximate the shape of an object before contact. In healthy subjects, hand shaping is known to occur early in reach under predominantly feedforward control. In patients with hemiparesis after stroke, execution of coordinated digit motion during grasping is impaired as a result of damage to the corticospinal tract. The question addressed here is whether patients with hemiparesis are able to compensate for their execution deficit with a qualitatively different grasp strategy that still allows them to differentiate hand posture to object shape. Subjects grasped a rectangular, concave, and convex object while wearing an instrumented glove. Reach-to-grasp was divided into three phases based on wrist kinematics: reach acceleration (reach onset to peak horizontal wrist velocity), reach deceleration (peak horizontal wrist velocity to reach offset), and grasp (reach offset to lift-off). Patients showed reduced finger abduction, proximal interphalangeal joint (PIP) flexion, and metacarpophalangeal joint (MCP) extension at object grasp across all three shapes compared with controls; however, they were able to partially differentiate hand posture for the convex and concave shapes using a compensatory strategy that involved increased MCP flexion rather than the PIP flexion seen in controls. Interestingly, shape-specific hand postures did not unfold initially during reach acceleration as seen in controls, but instead evolved later during reach deceleration, which suggests increased reliance on sensory feedback. These results indicate that kinematic analysis can identify and quantify within-limb compensatory motor control strategies after stroke. From a clinical perspective, quantitative study of compensation is important to better understand the process of recovery from brain injury. From a motor control perspective, compensation can be considered a model for how joint redundancy is exploited

A proximal point algorithm with generalized proximal distances to BEPs

OpenAIRE

Bento, G. C.; Neto, J. X. Cruz; Lopes, J. O.; Soares Jr, P. A.; Soubeyran, A.

2014-01-01

We consider a bilevel problem involving two monotone equilibrium bifunctions and we show that this problem can be solved by a proximal point method with generalized proximal distances. We propose a framework for the convergence analysis of the sequences generated by the algorithm. This class of problems is very interesting because it covers mathematical programs and optimization problems under equilibrium constraints. As an application, we consider the problem of the stability and change dyna...

Feedback attitude sliding mode regulation control of spacecraft using arm motion

Science.gov (United States)

Shi, Ye; Liang, Bin; Xu, Dong; Wang, Xueqian; Xu, Wenfu

2013-09-01

The problem of spacecraft attitude regulation based on the reaction of arm motion has attracted extensive attentions from both engineering and academic fields. Most of the solutions of the manipulator’s motion tracking problem just achieve asymptotical stabilization performance, so that these controllers cannot realize precise attitude regulation because of the existence of non-holonomic constraints. Thus, sliding mode control algorithms are adopted to stabilize the tracking error with zero transient process. Due to the switching effects of the variable structure controller, once the tracking error reaches the designed hyper-plane, it will be restricted to this plane permanently even with the existence of external disturbances. Thus, precise attitude regulation can be achieved. Furthermore, taking the non-zero initial tracking errors and chattering phenomenon into consideration, saturation functions are used to replace sign functions to smooth the control torques. The relations between the upper bounds of tracking errors and the controller parameters are derived to reveal physical characteristic of the controller. Mathematical models of free-floating space manipulator are established and simulations are conducted in the end. The results show that the spacecraft’s attitude can be regulated to the position as desired by using the proposed algorithm, the steady state error is 0.000 2 rad. In addition, the joint tracking trajectory is smooth, the joint tracking errors converges to zero quickly with a satisfactory continuous joint control input. The proposed research provides a feasible solution for spacecraft attitude regulation by using arm motion, and improves the precision of the spacecraft attitude regulation.

Effect of Stretching Combined With Ultrashort Wave Diathermy on Joint Function and Its Possible Mechanism in a Rabbit Knee Contracture Model.

Science.gov (United States)

Zhang, Quan Bing; Zhou, Yun; Zhong, Hua Zhang; Liu, Yi

2018-05-01

The aim of this study was to investigate the therapeutic effect of stretching combined with ultrashort wave on joint contracture and explore its possible mechanism. Thirty-two rabbits underwent unilateral immobilization of a knee joint at full extension to cause joint contracture. At 6 wks after immobilization, the rabbits were randomly divided into the following four groups: natural recovery group, stretching treatment group, ultrashort wave treatment group, and combined treatment group. For comparison, eight control group animals of corresponding age were also examined. The effect of stretching and ultrashort wave treatment on joint contracture was assessed by measuring the joint range of motion, evaluating the collagen deposition of joint capsule and assessing the mRNA and protein levels for transforming growth factor β1 in the joint capsule. The combined treatment group led to the best recovery of joint function. The combined treatment with stretching and ultrashort wave was more effective than stretching or ultrashort wave treatment alone against the synovial thickening of suprapatellar joint capsule, the collagen deposition of anterior joint capsule, and the elevated expression of transforming growth factor β1 in the joint capsule. Stretching combined with ultrashort wave treatment was effective in improving joint range of motion, reducing the biomechanical, histological, and molecular manifestations of joint capsule fibrosis in a rabbit model of extending joint contracture.

Hybrid FSWeld-bonded joint fatigue behaviour

Science.gov (United States)

Lertora, Enrico; Mandolfino, Chiara; Gambaro, Carla; Pizzorni, Marco

2018-05-01

Aluminium alloys, widely used in aeronautics, are increasingly involved in the automotive industry due to the good relationship between mechanical strength and specific weight. The lightening of the structures is the first objective, which allows the decreasing in the weight in motion. The use of aluminium alloys has also seen the introduction of the Friction Stir Welding (FSW) technique for the production of structural overlapping joints. FSW allows us to weld overlap joints free from defects, but with the presence of a structural notch further aggravated by the presence of a "hook" defect near the edge of the weld. Furthermore, FSW presents a weld penetration area connected to the tool geometry and penetration. The experimental activity will be focused on the combination of two different joining techniques, which can synergistically improve the final joint resistance. In particular, the welding and bonding process most commonly known as weld-bonding is defined as a hybrid process, as it combines two different junction processes. In this paper we analyse FSWelded AA6082 aluminium alloy overlapped joint with the aim of quantitatively evaluating the improvement provided by the presence of an epoxy adhesive between the plates. After optimising the weld-bonding process, the mechanical behaviour of welded joints will be analysed by static and dynamic tests. The presence of the adhesive should limit the negative effect of the structural notch inevitable in a FSW overlapped joint.

Multiple linear regression approach for the analysis of the relationships between joints mobility and regional pressure-based parameters in the normal-arched foot.

Science.gov (United States)

Caravaggi, Paolo; Leardini, Alberto; Giacomozzi, Claudia

2016-10-03

Plantar load can be considered as a measure of the foot ability to transmit forces at the foot/ground, or foot/footwear interface during ambulatory activities via the lower limb kinematic chain. While morphological and functional measures have been shown to be correlated with plantar load, no exhaustive data are currently available on the possible relationships between range of motion of foot joints and plantar load regional parameters. Joints' kinematics from a validated multi-segmental foot model were recorded together with plantar pressure parameters in 21 normal-arched healthy subjects during three barefoot walking trials. Plantar pressure maps were divided into six anatomically-based regions of interest associated to corresponding foot segments. A stepwise multiple regression analysis was performed to determine the relationships between pressure-based parameters, joints range of motion and normalized walking speed (speed/subject height). Sagittal- and frontal-plane joint motion were those most correlated to plantar load. Foot joints' range of motion and normalized walking speed explained between 6% and 43% of the model variance (adjusted R 2 ) for pressure-based parameters. In general, those joints' presenting lower mobility during stance were associated to lower vertical force at forefoot and to larger mean and peak pressure at hindfoot and forefoot. Normalized walking speed was always positively correlated to mean and peak pressure at hindfoot and forefoot. While a large variance in plantar pressure data is still not accounted for by the present models, this study provides statistical corroboration of the close relationship between joint mobility and plantar pressure during stance in the normal healthy foot. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effect of body orientation on proprioception during active and passive motions

NARCIS (Netherlands)

Niessen, M.H.M.; Veeger, H.E.J.; Janssen, T.W.J.

2009-01-01

Objective: To investigate whether passive and active reproduction of joint position, as well as detection of passive motion (as measures of a subject's proprioception) of the shoulder differ while sitting compared with lying supine. Design: Shoulder proprioception of 28 healthy subjects (age, 22.2 ±

Descriptive profile of hip rotation range of motion in elite tennis players and professional baseball pitchers.

Science.gov (United States)

Ellenbecker, Todd S; Ellenbecker, Gail A; Roetert, E Paul; Silva, Rogerio Teixeira; Keuter, Greg; Sperling, Fabio

2007-08-01

Repetitive loading to the hip joint in athletes has been reported as a factor in the development of degenerative joint disease and intra-articular injury. Little information is available on the bilateral symmetry of hip rotational measures in unilaterally dominant upper extremity athletes. Side-to-side differences in hip joint range of motion may be present because of asymmetrical loading in the lower extremities of elite tennis players and professional baseball pitchers. Cohort (cross-sectional) study (prevalence); Level of evidence, 1. Descriptive measures of hip internal and external rotation active range of motion were taken in the prone position of 64 male and 83 female elite tennis players and 101 male professional baseball pitchers using digital photos and computerized angle calculation software. Bilateral differences in active range of motion between the dominant and nondominant hip were compared using paired t tests and Bonferroni correction for hip internal, external, and total rotation range of motion. A Pearson correlation test was used to test the relationship between years of competition and hip rotation active range of motion. No significant bilateral difference (P > .005) was measured for mean hip internal or external rotation for the elite tennis players or the professional baseball pitchers. An analysis of the number of subjects in each group with a bilateral difference in hip rotation greater than 10 degrees identified 17% of the professional baseball pitchers with internal rotation differences and 42% with external rotation differences. Differences in the elite male tennis players occurred in only 15% of the players for internal rotation and 9% in external rotation. Female subjects had differences in 8% and 12% of the players for internal and external rotation, respectively. Statistical differences were found between the mean total arc of hip range of internal and external rotation in the elite tennis players with the dominant side being greater

Interventions for increasing ankle joint dorsiflexion: a systematic review and meta-analysis

OpenAIRE

Young, Rebekah; Nix, Sheree; Wholohan, Aaron; Bradhurst, Rachael; Reed, Lloyd

2013-01-01

Background Ankle joint equinus, or restricted dorsiflexion range of motion (ROM), has been linked to a range of pathologies of relevance to clinical practitioners. This systematic review and meta-analysis investigated the effects of conservative interventions on ankle joint ROM in healthy individuals and athletic populations. Methods Keyword searches of Embase, Medline, Cochrane and CINAHL databases were performed with the final search being run in August 2013. Studies were eligible for inclu...

Computerized bone density analysis of the proximal phalanx of the horse

International Nuclear Information System (INIS)

Thompson, K.N.; Cheung, T.K.; Putnam, M.

1996-01-01

This study utilized computed tomography to determine the density patterns and the subchondral bone thickness of the first phalanx of the horse. An image processing system and commercially available software were used to process the computed tomographic slices obtained from the first phalanges of a 2-year-old Thoroughbred horse. The thickness and density of the medial and lateral cortices in the mid-shaft of the bone were similar; however, the cortex on the dorsal aspect was more dense and extended farther toward the proximal and distal aspects of the bone than the cortex on the palmar aspect. Density of the cortical bone was highest at the region of the bone with the smallest diameter. The cortical bone density at mid-shaft was approximately 3.5 times the cancellous bone density at the proximal aspect and 2.5 times that at the distal aspect of the bone. A moderate correlation (r = 0.53, p < 0.01)was found between the subchondral bone density and thickness. Despite limited numbers of specimens used, this study demonstrated the potential applications of computed tomography for investigating equine joint mechanics and diseases

Tumoral calcinosis-like lesion of the proximal linea aspera

International Nuclear Information System (INIS)

Seeger, L.L.; Butler, D.L.; Eckardt, J.J.; Layfield, L.; Adams, J.S.

1990-01-01

Tumoral calcinosis is presently a poorly defined disease. In its classic form, it consists of multiple large foci of benign mineralization in the soft tissue adjacent to bone near large joints. Patients are generally of African descent and are adolescents or young adults at presentation. Both metabolic and traumatic etiologies have been proposed. We report six adult Caucasian patients with lesions that pathologically resembled tumoral calcinosis. All lesions were small (less than 3x3 cm) and were located along the proximal linea aspera lof the femur. All patients presented with pain. Because of the atypical patient population and the unusual size and location of the lesions, we refer to this process as a 'tumoral calcinosis-like lesion'. A typical radiographic appearance and location, together with appropriate clinical history, can strongly suggest this diagnosis. (orig.)

Technical concept and evaluation of a novel shoulder simulator with adaptive muscle force generation and free motion

Directory of Open Access Journals (Sweden)

Verjans Mark

2016-09-01

Full Text Available The human shoulder is one of the most complex joints of the human body, and due to the high range of motion and the complex soft tissue apparatus prone to injuries. Surgical therapies and joint replacements often lead to unsatisfactory results. To improve the understanding of the complex biomechanics of the shoulder, experimental investigations have to be conducted. For this purpose a new shoulder simulator with an innovative muscle force generation was developed. On the basis of a modular concept six artificial pneumatic muscles were integrated to represent the functionally most important muscles of the shoulder joint, whereby a free and controlled movement of the humerus can be conducted. For each muscle individual setpoints for muscle length control based on a user defined shoulder movement for any artificial or cadaver specimen are created by manual motion “Teach-In”. Additional to muscle forces and lengths, optical tracking and a joint force measurement is used to enable different biomechanical studies of the shoulder joint. This paper describes the technical setup as well as the control strategy and first results of its experimental functional validation.

Immediate effects of different treatments for the wrist joints of subdominant hands, using electromechanical reaction time.

Science.gov (United States)

Hu, Chunying; Huang, Qiuchen; Yu, Lili; Zhou, Yue; Gu, Rui; Cui, Yao; Ge, Meng; Xu, Yanfeng; Liu, Jianfeng

2016-08-01

[Purpose] The aim of this study was to examine the immediate effects of muscle strength training and neuromuscular joint facilitation distal resistance training on wrist joints by using electromechanical reaction time. [Subjects and Methods] The subjects were 12 healthy young people (24.2 ± 3.1 years, 169.7 ± 6.5 cm, 65.3 ± 12.6 kg). Two kinds of isotonic contraction techniques were applied on the wrist joint: the wrist joint extension muscle strength training and the wrist joint extension pattern of neuromuscular joint facilitation. The electromechanical reaction time, premotor time, and motor time of the left upper limb were measured before and after each intervention session of muscle strength training and neuromuscular joint facilitation. [Results] The neuromuscular joint facilitation group showed significant shortening of the electromechanical reaction time and motor time after the intervention. [Conclusion] These results suggest that the electromechanical reaction time and motor time of the wrist joint can be improved by neuromuscular joint facilitation together with proximal resistance training, which can be used as a new form of exercise for improving the functions of subdominant hand wrist joints.

Osteochondral lesions in distal tarsal joints of Icelandic horses reveal strong associations between hyaline and calcified cartilage abnormalities

Directory of Open Access Journals (Sweden)

CJ Ley

2014-03-01

Full Text Available Osteochondral lesions in the joints of the distal tarsal region of young Icelandic horses provide a natural model for the early stages of osteoarthritis (OA in low-motion joints. We describe and characterise mineralised and non-mineralised osteochondral lesions in left distal tarsal region joint specimens from twenty-two 30 ±1 month-old Icelandic horses. Combinations of confocal scanning light microscopy, backscattered electron scanning electron microscopy (including, importantly, iodine staining and three-dimensional microcomputed tomography were used on specimens obtained with guidance from clinical imaging. Lesion-types were described and classified into groups according to morphological features. Their locations in the hyaline articular cartilage (HAC, articular calcified cartilage (ACC, subchondral bone (SCB and the joint margin tissues were identified and their frequency in the joints recorded. Associations and correlations between lesion-types were investigated for centrodistal joints only. In centrodistal joints the lesion-types HAC chondrocyte loss, HAC fibrillation, HAC central chondrocyte clusters, ACC arrest and ACC advance had significant associations and strong correlations. These lesion-types had moderate to high frequency in centrodistal joints but low frequencies in tarsometatarsal and talocalcaneal-centroquartal joints. Joint margin lesion-types had no significant associations with other lesion-types in the centrodistal joints but high frequency in both the centrodistal and tarsometatarsal joints. The frequency of SCB lesion-types in all joints was low. Hypermineralised infill phase lesion-types were detected. Our results emphasise close associations between HAC and ACC lesions in equine centrodistal joints and the importance of ACC lesions in the development of OA in low-motion compression-loaded equine joints.

A rare case of chondroblastioma of the proximal tibia

International Nuclear Information System (INIS)

Gecov, P.; Terziev, I.; Hristoskova, R.; Georgiev, G.; Kinov, P.; Tivchev, P.

2011-01-01

The authors report a rare case of chondroblastoma which was localised in the proximal tibial epiphysis in a 14-year-old boy. The lesion was evaluated with routine roentgenography and computer tomography. The imaging techniques revealed eccentric lesion, predominantly in the medial part of the bone, periosteal reaction in the metaphysic, calcification and sclerosis. After diagnostic evaluation including biopsy, the lesion was treated surgically with curettage and grafting. He was followed up for two years with routine radiographs and physical examination. Two years after surgery the patient had no recurrence, no pain and had nearly full range of motion of the knee. Roentgenographic characteristics of the disease as well as differential diagnostics are discussed. In conclusion, imaging techniques should be supplemented with an open biopsy for the final diagnosis.

Lower limb joint kinetics in walking: the role of industry recommended footwear.

Science.gov (United States)

Keenan, Geoffrey S; Franz, Jason R; Dicharry, Jay; Della Croce, Ugo; Kerrigan, D Casey

2011-03-01

The effects of current athletic footwear on lower extremity biomechanics are unknown. The aim of this study was to examine the changes, if any, that occur in peak lower extremity net joint moments while walking in industry recommended athletic footwear. Sixty-eight healthy young adults underwent kinetic evaluation of lower extremity extrinsic joint moments while walking barefoot and while walking in current standard athletic footwear matched to the foot mechanics of each subject while controlling for speed. A secondary analysis was performed comparing peak knee joint extrinsic moments during barefoot walking to those while walking in three different standard footwear types: stability, motion control, and cushion. 3-D motion capture data were collected in synchrony with ground reaction force data collected from an instrumented treadmill. The shod condition was associated with a 9.7% increase in the first peak knee varus moment, and increases in the hip flexion and extension moments. These increases may be largely related to a 6.5% increase in stride length with shoes associated with increases in the ground reaction forces in all three axes. The changes from barefoot walking observed in the peak knee joint moments were similar when subjects walked in all three footwear types. It is unclear to what extent these increased joint moments may be clinically relevant, or potentially adverse. Nonetheless, these differences should be considered in the recommendation as well as the design of footwear in the future. Copyright © 2010 Elsevier B.V. All rights reserved.

Use of a Proximity Sensor Switch for "Hands Free" Operation of Computer-Based Video Prompting by Young Adults with Moderate Intellectual Disability

Science.gov (United States)

Ivey, Alexandria N.; Mechling, Linda C.; Spencer, Galen P.

2015-01-01

In this study, the effectiveness of a "hands free" approach for operating video prompts to complete multi-step tasks was measured. Students advanced the video prompts by using a motion (hand wave) over a proximity sensor switch. Three young adult females with a diagnosis of moderate intellectual disability participated in the study.…

Incarceration of the medial collateral ligament in the intercondylar notch following proximal avulsion

Energy Technology Data Exchange (ETDEWEB)

Walton, Edward [Fiona Stanley Hospital, Department of Radiology, Perth, Western Australia (Australia); Williams, Martin [North Bristol NHS Trust, Department of Radiology, Bristol (United Kingdom); Robinson, James R. [Bristol Knee Group, Avon Orthopaedic Centre, Bristol (United Kingdom)

2017-11-15

Intra-articular entrapment of the medial collateral ligament (MCL) is a rare but recognised complication of traumatic injury to the posteromedial corner (PMC) of the knee. Considering the MCL is the most commonly injured ligament of the knee this complication is extremely rare with only a handful of cases describing MCL entrapment following distal avulsion of the MCL. We present the first known case of MCL entrapment following proximal avulsion of the MCL and posterior oblique ligament (POL) with the mid-substance of the MCL becoming entrapped in the joint, lying on the superior surface of the medial meniscus and extending up into the intercondylar notch. In addition, the medial patellar retinaculum was also entrapped in the medial aspect of the medial patellofemoral joint. MCL entrapment is best treated with expeditious surgical intervention and it is therefore crucial that the MRI findings are not overlooked. Details of the clinical assessment, MRI and operative findings are presented with a literature review of MCL entrapment. (orig.)

Incarceration of the medial collateral ligament in the intercondylar notch following proximal avulsion

International Nuclear Information System (INIS)

Walton, Edward; Williams, Martin; Robinson, James R.

2017-01-01

Intra-articular entrapment of the medial collateral ligament (MCL) is a rare but recognised complication of traumatic injury to the posteromedial corner (PMC) of the knee. Considering the MCL is the most commonly injured ligament of the knee this complication is extremely rare with only a handful of cases describing MCL entrapment following distal avulsion of the MCL. We present the first known case of MCL entrapment following proximal avulsion of the MCL and posterior oblique ligament (POL) with the mid-substance of the MCL becoming entrapped in the joint, lying on the superior surface of the medial meniscus and extending up into the intercondylar notch. In addition, the medial patellar retinaculum was also entrapped in the medial aspect of the medial patellofemoral joint. MCL entrapment is best treated with expeditious surgical intervention and it is therefore crucial that the MRI findings are not overlooked. Details of the clinical assessment, MRI and operative findings are presented with a literature review of MCL entrapment. (orig.)

Study on fundamental mechanism of nuclear advanced robot. An analysis of fundamental motion with pliability for end-effector of advanced robot

International Nuclear Information System (INIS)

Ohki, Arahiko; Hirano, Sigeo; Yoshida, Tomoya.

1997-01-01

Most of present robots only perform works simulating human action, but hereafter, it is required to do advanced works smoothly with robots in place of men. Among the mechanisms of high performance robots, as one of the important components that do advanced action and adapt to diversified purposes, there is manipulator. The manipulator comprises arm and end effector. In the process of heightening robot performance hereafter, the reproduction of detailed action is the indispensable subject of research. The object of carrying out this research is to elucidate the possibility of giving the functions close to those of delicate human hands to end effector. First, the joints of human hands were measured, and based on these data, the equation for determining the change of angle in relation to the time of motion of respective joints was established. Further, the simulation of simple actions was carried out, and the concept of the mechanism model was built by analyzing the motion similar to human body. The structural difference in the joints of human and manipulator, the measurement of hands and the analysis of the motion of hand joints are reported. (K.I.)

Estimation of ligament strains and joint moments in the ankle during a supination sprain injury.

Science.gov (United States)

Wei, Feng; Fong, Daniel Tik-Pui; Chan, Kai-Ming; Haut, Roger C

2015-01-01

This study presents the ankle ligament strains and ankle joint moments during an accidental injury event diagnosed as a grade I anterior talofibular ligament (ATaFL) sprain. A male athlete accidentally sprained his ankle while performing a cutting motion in a laboratory setting. The kinematic data were input to a three-dimensional rigid-body foot model for simulation analyses. Maximum strains in 20 ligaments were evaluated in simulations that investigated various combinations of the reported ankle joint motions. Temporal strains in the ATaFL and the calcaneofibular ligament (CaFL) were then compared and the three-dimensional ankle joint moments were evaluated from the model. The ATaFL and CaFL were highly strained when the inversion motion was simulated (10% for ATaFL and 12% for CaFL). These ligament strains were increased significantly when either or both plantarflexion and internal rotation motions were added in a temporal fashion (up to 20% for ATaFL and 16% for CaFL). Interestingly, at the time strain peaked in the ATaFL, the plantarflexion angle was not large but apparently important. This computational simulation study suggested that an inversion moment of approximately 23 N m plus an internal rotation moment of approximately 11 N m and a small plantarflexion moment may have generated a strain of 15-20% in the ATaFL to produce a grade I ligament injury in the athlete's ankle. This injury simulation study exhibited the potentially important roles of plantarflexion and internal rotation, when combined with a large inversion motion, to produce a grade I ATaFL injury in the ankle of this athlete.

An Incidental Finding of a Talonavicular and Talocalcaneal Joint Coalition After a Tibial Pilon Fracture: A Case Report.

Science.gov (United States)

Godoy, Heidi M; Micciche, Mark J

It has been proposed that patients with talocalcaneal and talonavicular coalitions have decreased ankle joint range of motion. It has also been reported that rotational forces regularly absorbed by the talocalcaneal joint are transferred to the ankle joint in patients with coalitions, increasing the stress on the ankle joint after trauma. To the best of our knowledge, only 1 reported study has detailed the increased stress placed on the ankle joint secondary to a coalition. We present a case study of a 53-year-old female who experienced a traumatic fall and subsequent right ankle fracture. Advanced imaging studies revealed a comminuted tibial pilon fracture and talocalcaneal and talonavicular joint coalitions. She underwent open reduction and internal fixation for treatment of the fracture, and the coalitions were not treated because they were asymptomatic. She was kept non-weightbearing for 6 weeks postoperatively and was returned to a regular sneaker at 10 weeks postoperatively. The postoperative films revealed stable intact fixation and pain-free gait with no increased restriction in her ankle joint range of motion. The hardware was removed at 13 months postoperatively. She had not experienced increased pain or arthritic changes at 15 months postoperatively. Copyright © 2017 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

Time-frequency analysis of human motion during rhythmic exercises.

Science.gov (United States)

Omkar, S N; Vyas, Khushi; Vikranth, H N

2011-01-01

Biomechanical signals due to human movements during exercise are represented in time-frequency domain using Wigner Distribution Function (WDF). Analysis based on WDF reveals instantaneous spectral and power changes during a rhythmic exercise. Investigations were carried out on 11 healthy subjects who performed 5 cycles of sun salutation, with a body-mounted Inertial Measurement Unit (IMU) as a motion sensor. Variance of Instantaneous Frequency (I.F) and Instantaneous Power (I.P) for performance analysis of the subject is estimated using one-way ANOVA model. Results reveal that joint Time-Frequency analysis of biomechanical signals during motion facilitates a better understanding of grace and consistency during rhythmic exercise.

LMFBR flexible pipe joint development program. Annual technical progress report, government fiscal year 1977

International Nuclear Information System (INIS)

1978-01-01

Currently, the ASME Boiler and Pressure Vessel Code does not allow the use of flexible pipe joints (bellows) in Section III, Class 1 reactor primary piping systems. Studies have shown that the primary piping loops of LMFBR's could be simplified by using these joints. This simplification translates directly into shorter primary piping runs and reduced costs for the primary piping system. Further cost savings result through reduced vault sizes and reduced containment building diameter. In addition, the use of flexible joints localizes the motions from thermally-induced piping growth into components which are specifically designed to accommodate this motion. This reduces the stress levels in the piping system and its components. It is thus economically and structurally important that flexible piping joints be available to the LMFBR designer. The overall objective of the Flexible Joint Program is to provide this availability. This will be accomplished through the development of ASME rules which allow the appropriate use of such joints in Section III, Class 1 piping systems and through the development and demonstration of construction methods which satisfy these rules. The rule development includes analytic and testing methodology formulations which will be supported by subscale bellows testing. The construction development and demonstration encompass the design, fabrication, and in-sodium testing of prototypical LMFBR plant-size flexible pipe joints which meet all ASME rule requirements. The satisfactory completion of these developmental goals will result in an approved flexible pipe joint design for the LMFBR. Progress is summarized in the following efforts undertaken during 1977 to accomplish these goals: (1) code case support, (2) engineering and design, (3) material development, (4) testing, and (5) manufacturing development

An unusual case of posterior elbow dislocation with proximal radioulnar translocation.

Science.gov (United States)

Gómez Robledo, J; Díez Lizuaín, M L

2018-03-07

We present a 9-year-old girl who suffered a posterior dislocation of the right elbow with a proximal translocation between the ulna and the radius. It is a type of exceptional dislocation which in our case was not accompanied by lesions of the joint surfaces of the elbow unlike most cases already published. This article stresses the importance of making an early diagnosis of this variety of dislocation; this is the best way to prevent it from going unnoticed. The use of Computed Tomography (CT) helped this early diagnosis, enabling an immediate closed orthopaedic reduction and achieving a cure without sequelae. Copyright © 2018 SECOT. Publicado por Elsevier España, S.L.U. All rights reserved.

Relationship of orthopedic examination, goniometric measurements, and radiographic signs of degenerative joint disease in cats.

Science.gov (United States)

Lascelles, B Duncan X; Dong, Yaa-Hui; Marcellin-Little, Denis J; Thomson, Andrea; Wheeler, Simon; Correa, Maria

2012-01-27

Available information suggests a mismatch between radiographic and orthopedic examination findings in cats with DJD. However, the extent of the discrepancy between clinical and radiographic signs of OA in companion animals has not been described in detail. This study aimed to evaluate the relationship between orthopedic examination findings, joint goniometry, and radiographic signs of DJD in 100 cats, in a prospective observational design. Cat temperament, pain response to palpation, joint crepitus, effusion and thickening were graded. Radiographs of appendicular joints and the axial skeleton were made under sedation. Joint motion was measured by use of a plastic goniometer before and after sedation. Associations between radiographic degenerative joint disease (DJD) and examination findings were assessed to determine sensitivity, specificity and likelihood estimations. Pain response to palpation was elicited in 0-67% of the joints with DJD, with a specificity ranging from 62-99%; crepitus was detected in 0-56% of the joints and its specificity varied between 87 and 99%; for effusion, values ranged between 6 and 38% (specificity, 82-100%), and thickening, 0-59% (specificity, 74-99%). Joints with DJD tended to have a decreased range of motion. The presence of pain increased the odds of having DJD in the elbow (right: 5.5; left: 4.5); the presence of pain in the lower back increased the odds of spinal DJD being present (2.97 for lumbar; 4.67 for lumbo-sacral). Radiographic DJD cannot be diagnosed with certainty using palpation or goniometry. However, negative findings tend to predict radiographically normal joints. Palpation and goniometry may be used as a tool to help to screen cats, mostly to rule out DJD.

Relationship of orthopedic examination, goniometric measurements, and radiographic signs of degenerative joint disease in cats

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Lascelles B Duncan X