Pseudarthrosis of radial shaft with dislocation of heads of radial and ulnar bones (case report

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M. E. Puseva

2013-01-01

Full Text Available The authors presented a rare clinical case - the injury of forearm complicated by the formation of the pseudarthrosis of the radial shaft in combination with old dislocation of heads the radius and ulna. The differentiated approach to the choice of surgical tactics was proposed, which consists of several consistent stages: taking free autotransplant from the crest of iliac bone, resection of pseudarthrosis of radius with replacement of the bone defect by the graft for restoration of anatomic length, conducting combined strained osteosynthesis and elimination of dislocation of a head of radial and ulnar bones by transosseous osteosynthesis. The chosen treatment strategy allowed to restore the anatomy and function of the upper extremity.

Press-fit bipolar radial head arthroplasty, midterm results

NARCIS (Netherlands)

Kodde, Izaäk F.; Heijink, Andras; Kaas, Laurens; Mulder, Paul G. H.; van Dijk, C. Niek; Eygendaal, Denise

2016-01-01

Theoretical advantages of bipolar compared with monopolar radial head arthroplasty include better accommodation of radiocapitellar malalignment, reduction of capitellar abrasion, and reduction of stress at the bone-implant interfaces. Our purpose was to report the midterm results of press-fit

Effect of radial head implant shape on joint contact area and location during static loading.

Science.gov (United States)

Shannon, Hannah L; Deluce, Simon R; Lalone, Emily A; Willing, Ryan; King, Graham J W; Johnson, James A

2015-04-01

To examine the effect of implant shape on radiocapitellar joint contact area and location in vitro. We used 8 fresh-frozen cadaveric upper extremities. An elbow loading simulator examined joint contact in pronation, neutral rotation, and supination with the elbow at 90° flexion. Muscle tendons were attached to pneumatic actuators to allow for computer-controlled loading to achieve the desired forearm rotation. We performed testing with the native radial head, an axisymmetric implant, a reverse-engineered patient-specific implant, and a population-based quasi-anatomic implant. Implants were inserted using computer navigation. Contact area and location were quantified using a casting technique. We found no significant difference between contact locations for the native radial head and the 3 implants. All of the implants had a contact area lower than the native radial head; however, only the axisymmetric implant was significantly different. There was no significant difference in contact area between implant shapes. The similar contact areas and locations of the 3 implant designs suggest that the shape of the implant may not be important with respect to radiocapitellar joint contact mechanics when placed optimally using computer navigation. Further work is needed to explore the sensitivity of radial head implant malpositioning on articular contact. The lower contact area of the radial head implants relative to the native radial head is similar to previous benchtop studies and is likely the result of the greater stiffness of the implant. Radial head implant shape does not appear to have a pronounced influence on articular contact, and both axisymmetric and anatomic metal designs result in elevated cartilage stress relative to the intact state. Copyright © 2015 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

Evaluation of the effects of the radial constant-head boundary in slug tests

Science.gov (United States)

Dai, Yunfeng; Zhou, Zhifang; Zhao, Yanrong; Cui, Ziteng

2015-03-01

A semianalytical model of slug tests, conducted in a completely penetrating well within a radial constant-head boundary, was derived. The model, based on the Cooper et al. (1967) model, estimates the hydraulic conductivity and storage coefficient through the matching of type curves. Type curves of the semianalytical solution were plotted, and the effect of the distance of the radial constant-head boundary is discussed. For different storage coefficients, the critical distances of the effect of the constant-head boundary were determined. The effect of the storage coefficient on the response of the water head in slug tests with a radial constant-head boundary of a certain distance is also shown. To verify the model, laboratory slug-test experiments were carried out using a cylindrical test platform, in which an artificial confined coarse-sand aquifer was built. Pumping tests were also executed using the test platform. The Cooper et al. (1967) model and new semianalytical model were used to analyze measurements; the hydraulic conductivity and storage coefficient determined using the two methods were compared to demonstrate the importance of the radial constant-head boundary. A model considering the inertial effect was also used to analyze the slug-test measurements, and although the water head response did not oscillate greatly, the inertial effect affected the slug-test calculation result. The laboratory experiments indicate that the proposed semianalytical model is reasonable and reliable. Cooper HH, Bredehoeft JD, Papadopulos IS (1967) Response of a finite-diameter well to an instantaneous charge of water, Water Resour Res 3(1):263-269.

Isolated posterior dislocation of the radial head in an adult.

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Negi A

1992-07-01

Full Text Available Isolated posterior dislocation of the radial head was detected on X-ray in a patient following a vehicular accident. Such a dislocation without an associated fracture is extremely rare in adults. Immobilization of the elbow in full pronation and 90 degrees flexion for 4 weeks normalized the position of the head of the radius.

Mechanical analysis of a ceramic head being part of a modular hip prosthesis

International Nuclear Information System (INIS)

Ravagli, Ermenegildo

1998-04-01

This report still pursues the aim of carrying out a systematic mechanical analysis of a ceramic head being part of a modular hip prosthesis, in order to characterize it exhaustively, i.e. to assess its performances and some of its main specifications. Here in particular the aim is to locate the stress of the head when it undergoes the load transferred by the stem, presuming that the stem-head mating is not perfect, but there is a conical error called of the 2. type, to which corresponds a stem summit angle smaller than the one in the head hole. This conical error changes considerably the head stress and therefore this study is considered decisive for a later correct assessment of its resistance to breaking. This study is performed in the frame of the STRIDE-CETMA Project, which is aimed at founding and developing a Centre for technologically advanced materials in Brindisi (Italy) Technology Park [it

Fabrication and characterization of DLC coated microdimples on hip prosthesis heads.

Science.gov (United States)

Choudhury, Dipankar; Ay Ching, Hee; Mamat, Azuddin Bin; Cizek, Jan; Abu Osman, Noor Azuan; Vrbka, Martin; Hartl, Martin; Krupka, Ivan

2015-07-01

Diamond like carbon (DLC) is applied as a thin film onto substrates to obtain desired surface properties such as increased hardness and corrosion resistance, and decreased friction and wear rate. Microdimple is an advanced surface modification technique enhancing the tribological performance. In this study, DLC coated microdimples were fabricated on hip prosthesis heads and their mechanical, material and surface properties were characterized. An Electro discharge machining (EDM) oriented microdrilling was utilized to fabricate a defined microdimple array (diameter of 300 µm, depth of 70 µm, and pitch of 900 µm) on stainless steel (SS) hip prosthesis heads. The dimpled surfaces were then coated by hydrogenated amorphous carbon (a-C:H) and tetrahedral amorphous carbon (Ta-C) layers by using a magnetron sputtering technology. A preliminary tribology test was conducted on these fabricated surfaces against a ceramic ball in simulated hip joint conditions. It was found that the fabricated dimples were perpendicular to the spherical surfaces and no cutting-tools wear debris was detected inside the individual dimples. The a-C:H and Ta-C coatings increased the hardness at both the dimple edges and the nondimpled region. The tribology test showed a significant reduction in friction coefficient for coated surfaces regardless of microdimple arrays: the lowest friction coefficient was found for the a-C:H samples (µ = 0.084), followed by Ta-C (µ = 0.119), as compared to the SS surface (µ = 0.248). © 2014 Wiley Periodicals, Inc.

The incidence of associated fractures of the upper limb in fractures of the radial head

NARCIS (Netherlands)

Kaas, Laurens; van Riet, Roger P.; Vroemen, Jos P. A. M.; Eygendaal, Denise

2008-01-01

Radial head fractures are common injuries. In American publications, one-third of the patients with these fractures have been shown to have associated injuries. The aim of this retrospective study is to describe the epidemiology of radial head fractures and associated fractures of the ipsilateral

Simultaneous bilateral Mason type IIb radial head fractures in a young female: Was an increased carrying angle the cause?

LENUS (Irish Health Repository)

2015-01-01

Radial head fracture is the most common type of elbow fracture in adults. It results from a fall on an outstretched hand. However, simultaneous bilateral radial head fractures are extremely rare. We report a case of simultaneous bilateral mason type IIb radial head fractures in a young female, which was treated nonoperatively with excellent results

The transverse force experienced by the radial head during axial loading of the forearm: A cadaveric study.

Science.gov (United States)

Orbay, Jorge L; Mijares, Michael R; Berriz, Cecilia G

2016-01-01

When designing a radial head replacement, the magnitude and direction of forces applied across the proximal radio-ulnar joint (PRUJ) and the radiocapitellar joint must be included. These designs often focus on axial loads transmitted to the radial head by the capitellum; however, the radial head also bears a significant transverse force at the PRUJ. Load transmission by the central band of the interosseous ligament induces a force component in a lateral direction perpendicular to the axis of the limb, which is borne by the articular surfaces of the proximal and distal radio-ulnar joints. The objective of this study is to establish the relationship between distally applied axial forces and proximal transverse reaction forces. Five cadaveric, human forearms with intact interosseous membranes were used to measure the magnitude of transversely-directed forces experienced by the radial head during axial loading of the forearm at the lunate fossa. A Mark-10 test stand applied a gradual and continuous axial load on the articular surface of the distal radius. A Mark-10 force gauge measured the resultant transverse force experienced by the radial head in the proximal radioulnar joint. Classical mechanics and static force analysis were applied in order to predict lateral force values that would occur when the interosseous ligament is treated as the major load transmitter between the radius and ulna. Acquired data show that the radial head bears a force in the transverse direction that averages 18% (SD 3.89%) in magnitude of the axial force applied at the wrist. This figure is in close accordance with the predicted value of 22% that was calculated by way of free-body plotting. Physiologic forearm loading results in a clinically significant transverse force component transmitted through the interosseous ligament complex. The existence of transverse forces in the human forearm may explain clinical problems seen after radial head resection and suggest that radial head implants

ARTHROSCOPIC METHOD OF THE RADIAL HEAD FRACTURE OSTEOSYNTHESIS (СASE REPORT

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I. A. Kuznetsov

2016-01-01

Full Text Available Radial head fractures constitute about 3% of all fractures and 30% within the group of elbow joint injuries. Conventional open surgical treatment is accompanied by an extensive soft tissue incision and sometimes by capsule release for adequate visualization. Arthroscopic methods feature relatively insignificant soft tissue trauma, allow to reduce pain syndrome in postoperative period and to accelerate rehabilitation. Besides, arthroscopy improves surgical view in cases of intraarticular fractures and facilitates a better anatomical reduction of articular surface. The authors demonstrate a clinical case of a patient with closed fractures of radial head and ulna coronoid process with displacement of left elbow joint fragments where arthroscopic surgery provided for good anatomical and functional results.

A Case of Acute Prosthesis Migration after Femoral Head Replacement due to Osteomalacia by FGF23-Induced Tumor

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Shinya Hayashi

2012-01-01

Full Text Available Fibroblast growth factor 23 (FGF23 was recently identified as an important factor involved in the development of hypophosphatemic rickets and osteomalacia. We experienced a rare case of acute prosthesis migration after hemihip arthroplasty due to FGF23-induced tumor. The patient underwent femoral head replacement because of femoral neck fracture, but prosthesis migration was occurred at 1 week after operation. The patient took various examinations, and FGF23-induced tumor was found in his right wrist. The tumor was resected, and he underwent total hip arthroplasty 8 month later. Finally, he was able to obtain free gait without pain.

Radiographic loss of contact between radial head fracture fragments is moderately reliable

NARCIS (Netherlands)

Bruinsma, Wendy E.; Guitton, Thierry; Ring, David; Eng, Kevin; Jokhi, Vispi; Oloruntoba, David O.; Jain, Sanjev; Melvanki, Parag; Frihagen, Frede; McGraw, Iain; Lenzlinger, Philipp; Ponsen, K. J.; Schmidt, Andrew; Ciritsis, Bernhard; Conflitti, Joseph M.; Turina, Matthias; Poolman, Rudolf W.; Liem, Ronald; Gulve, R. S.; Wagg, James; Kloen, Peter; Grosso, Elena; Mormino, Matt; Choudhari, Pradeep; Zura, Robert D.; Pesantez, Rodrigo; Thomas, George; Brink, Peter; Swiontkowski, Marc; Beingessner, Daphne; Schep, Niels; Kanakaris, Nikolaos; Peters, R. W.; Andrew, J.; Trenholm, I.; Mica, Ladislav; Verhofstad, M. H. J.; Taitsman, Lisa; Hernandez, Daniel; Harris, Ian; Egol, Kenneth; Jeray, Kyle; Borris, Lars C.; Barquet, Antonio; Kellam, James; Marsh, John L.; Hobby, Jonathan L.; Eygendaal, Denise; Goslings, J. C.; Kleinlugtenbelt, I. J. V.

2014-01-01

Loss of contact between radial head fracture fragments is strongly associated with other elbow or forearm injuries. If this finding has adequate interobserver reliability, it could help examiners identify and treat associated ligament injuries and fractures (eg, forearm interosseous ligament injury

An Osteoma Located on the Radial Head: A Case Report

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Seyitali Gumustas

2013-06-01

Full Text Available Osteoma are seen mostly at paranasal sinuses and cranium while it is rare at long bones. Osteomas may misdiagnosed as osteochondroma, lateral epicondylitis and other clinic pathologies, hence it is seen probably more common than reported on literature. Excisional biopsy is enough for treatment, and recurrence is rare after excision. We present a rarely seen osteoma case, which is radial head, located.

Costo-osteochondral graft for post-traumatic osteonecrosis of the radial head in an adolescent boy.

Science.gov (United States)

Iwai, S; Sato, K; Nakamura, T; Okazaki, M; Itoh, Y; Toyama, Y; Ikegami, H

2011-01-01

We present a case of post-traumatic osteonecrosis of the radial head in a 13-year-old boy which was treated with costo-osteochondral grafts. A satisfactory outcome was seen at a follow-up of two years and ten months. Although costo-osteochondral grafting has been used in the treatment of defects in articular cartilage, especially in the hand and the elbow, the extension of the technique to manage post-traumatic osteonecrosis of the radial head in a child has not previously been reported in the English language literature. Complete relief of pain was obtained and an improvement in the range of movement was observed. The long-term results remain uncertain.

Evaluation of Radiocapitellar Arthritis in Patients with a Second Radiograph at Least 2 Years after Nonoperative Treatment of an Isolated Radial Head Fracture

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Amir R. Kachooei

2017-11-01

Full Text Available Background: To study if patients that have a second radiograph 2 or more years after nonoperative treatment of an isolated radial head fracture have radiocapitellar osteoarthritis (RC OA. Methods: We used the database of 3 academic hospitals in one health system from 1988 to 2013 to find patients with isolated radial head fractures (no associated ligament injury or fracture that had a second elbow radiograph after more than 2 years from the initial injury. Of 887 patients with isolated radial head fractures, 54 (6% had an accessible second radiograph for reasons of a second injury (57%, pain (30%, or follow-up visit (13%. Two orthopedic surgeons independently classified the radial head fractures on the initial radiographs using the Broberg and Morrey modified Mason classification, and assessed the development of RC OA on the final radiograph using a binary system (yes/no. Results: Four out of 54 (7.5% patients had RC OA, one with isolated RC arthrosis that seemed related to capitellar cartilage injury, and 3 that presented with pain and had global OA (likely primary osteoarthritis. Conclusion: With the caveat that some percentage of patients may have left our health system during the study period, about 1 in 887 patients (0.1% returns with isolated radiocapitellar arthritis after an isolated radial head fracture, and this may relate to capitellar injury rather than attrition. Patients with isolated radial head fractures can consider post-traumatic radiocapitellar arthritis a negligible risk.

Head movements evoked in alert rhesus monkey by vestibular prosthesis stimulation: implications for postural and gaze stabilization.

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Diana E Mitchell

Full Text Available The vestibular system detects motion of the head in space and in turn generates reflexes that are vital for our daily activities. The eye movements produced by the vestibulo-ocular reflex (VOR play an essential role in stabilizing the visual axis (gaze, while vestibulo-spinal reflexes ensure the maintenance of head and body posture. The neuronal pathways from the vestibular periphery to the cervical spinal cord potentially serve a dual role, since they function to stabilize the head relative to inertial space and could thus contribute to gaze (eye-in-head + head-in-space and posture stabilization. To date, however, the functional significance of vestibular-neck pathways in alert primates remains a matter of debate. Here we used a vestibular prosthesis to 1 quantify vestibularly-driven head movements in primates, and 2 assess whether these evoked head movements make a significant contribution to gaze as well as postural stabilization. We stimulated electrodes implanted in the horizontal semicircular canal of alert rhesus monkeys, and measured the head and eye movements evoked during a 100 ms time period for which the contribution of longer latency voluntary inputs to the neck would be minimal. Our results show that prosthetic stimulation evoked significant head movements with latencies consistent with known vestibulo-spinal pathways. Furthermore, while the evoked head movements were substantially smaller than the coincidently evoked eye movements, they made a significant contribution to gaze stabilization, complementing the VOR to ensure that the appropriate gaze response is achieved. We speculate that analogous compensatory head movements will be evoked when implanted prosthetic devices are transitioned to human patients.

[Imaging evaluation on adaptability of proximal humeral anatomy after shoulder replacement with individualized shoulder prosthesis].

Science.gov (United States)

Shi, Youxing; Tang, Kanglai; Yuan, Chengsong; Tao, Xu; Wang, Huaqing; Chen, Bo; Guo, Yupeng

2015-03-24

Modern shoulder prosthesis has evolved through four generations. And the fourth generation technology has a core three-dimensional design of restoring 3D reconstruction of proximal humeral anatomy. Thus a new shoulder prosthesis is developed on the basis of the technology of 3D prosthesis. Assessment of whether shoulder prosthesis can restore individualized reconstruction of proximal humeral anatomy is based on the adaptability of proximal humeral anatomy. To evaluate the adaptability of proximal humeral anatomy through measuring the parameters of proximal humeral anatomy after shoulder replacement with individualized shoulder prosthesis and compare with normal data. The parameters of proximal humeral anatomy were analyzed and evaluated for a total of 12 cases undergoing shoulder replacement with individualized shoulder prosthesis. The relevant anatomical parameters included neck-shaft angle (NSA), retroversion angle (RA), humeral head height (HH) and humeral head diameter (HD). And the anatomical parameters were compared with the data from normal side. All underwent shoulder replacement with individualized shoulder prosthesis. The postoperative parameters of proximal humeral anatomy were compared with those of normal side. And the difference of NSA was 0.05). Individualized shoulder prosthesis has excellent adaptability to shoulder. All core parameters are freely adjustable and specification models may be optimized. With matching tools, individualized shoulder prosthesis improves the accuracy and reliability in shoulder replacement.

Elbow joint stability following experimental osteoligamentous injury and reconstruction

DEFF Research Database (Denmark)

Deutch, Søren R; Jensen, Steen Lund; Tyrdal, Stein

2003-01-01

Elbow joint dislocation was simulated in cadaveric specimens to quantify laxity induced by radial head and coronoid process lesions, either alone or in combination with collateral ligament insufficiency. The effects of lateral ligament reconstruction and radial head prosthesis replacement were also...

[Tripolar arthroplasty for recurrent total hip prosthesis dislocation].

Science.gov (United States)

Beaulé, P-E; Roussignol, X; Schmalzried, T-P; Udomkiat, P; Amstutz, H-C; Dujardin, F-H

2003-05-01

The purpose of this study was to assess the results of revision surgery for recurrent total hip prosthesis dislocation using a tripolar prosthesis composed of a conventional stem with a mobile head of an intermediary prosthesis measuring more than 40 mm and a modified cup. This technique was used in two centers in Rouen France and Los Angeles USA. Twenty-one hips in 21 patients were operated on. The mobile heads measured 40 to 47 mm. Mean patient age was 70 years (range 29-92). The indication for the tripolar prosthesis was reserved for extremely unstable hips in patients with major risk factors for recurrent dislocation. These 21 patients had experienced 95 dislocations. The acetabular cup was custom-made for the large-diameter heads. A cemented polyethylene cup was used in 14 cases and a press-fit metal-backed around a polyethylene insert in 7. The polyethylene thickness varied from 6.5 to 16 mm for the cemented cups and 4 to 5 mm for the press-fit cups. Fourteen femoral stems were left in place as were two press-fit cups where only the inserts were changed. Mean follow-up was 5.4 years (range 3-11.8). There has been no recurrent dislocation for 20 hips. One patient experienced a dislocation one week after surgery which required a second revision procedure to reposition the acetabular implant. Final outcome was good at 7.6 years for this hip. One patient who had not had any recurrent dislocation died 4 years after the revision surgery due to a cause unrelated to the prosthesis. Two patients were lost to follow-up at 3.7 and 6 years, both were pain free and had no radiological anomalies. Infection occurred in one patient undergoing chemotherapy for a myeloma; the head and neck had to be resected. For the 20 other patients, functional outcome, assessed with the UCLA score, showed improvement in pain (5.8 preoperatively, 9.2 at last follow-up), walking (4.8 and 8 respectively), function (4 and 6 respectively), and daily activities (3.3 and 5.2 respectively). A

Life Estimation of Hip Joint Prosthesis

Science.gov (United States)

Desai, C.; Hirani, H.; Chawla, A.

2015-07-01

Hip joint is one of the largest weight-bearing structures in the human body. In the event of a failure of the natural hip joint, it is replaced with an artificial hip joint, known as hip joint prosthesis. The design of hip joint prosthesis must be such so as to resist fatigue failure of hip joint stem as well as bone cement, and minimize wear caused by sliding present between its head and socket. In the present paper an attempt is made to consider both fatigue and wear effects simultaneously in estimating functional-life of the hip joint prosthesis. The finite element modeling of hip joint prosthesis using HyperMesh™ (version 9) has been reported. The static analysis (load due to the dead weight of the body) and dynamic analysis (load due to walking cycle) have been described. Fatigue life is estimated by using the S-N curve of individual materials. To account for progressive wear of hip joint prosthesis, Archard's wear law, modifications in socket geometry and dynamic analysis have been used in a sequential manner. Using such sequential programming reduction in peak stress has been observed with increase in wear. Finally life is estimated on the basis of socket wear.

X-ray evidence of low-energy photon therapy for cervical lordosis restoration and radial head spur healing

Science.gov (United States)

Fitz-Ritson, Donald; Filonenko, Natalia; Salansky, Norman M.

1994-09-01

X rays were used for low energy photon therapy (LEPT) efficacy assessment for cervical lordosis restoration and radial head spur healing. Two cases, their evaluation, and treatment are discussed along with the follow-up results.

Radial displacement of clinical target volume in node negative head and neck cancer

International Nuclear Information System (INIS)

Jeon, Wan; Wu, Hong Gyun; Song, Sang Hyuk; Kim, Jung In

2012-01-01

To evaluate the radial displacement of clinical target volume in the patients with node negative head and neck (H and N) cancer and to quantify the relative positional changes compared to that of normal healthy volunteers. Three node-negative H and N cancer patients and fi ve healthy volunteers were enrolled in this study. For setup accuracy, neck thermoplastic masks and laser alignment were used in each of the acquired computed tomography (CT) images. Both groups had total three sequential CT images in every two weeks. The lymph node (LN) level of the neck was delineated based on the Radiation Therapy Oncology Group (RTOG) consensus guideline by one physician. We use the second cervical vertebra body as a reference point to match each CT image set. Each of the sequential CT images and delineated neck LN levels were fused with the primary image, then maximal radial displacement was measured at 1.5 cm intervals from skull base (SB) to caudal margin of LN level V, and the volume differences at each node level were quantified. The mean radial displacements were 2.26 (±1.03) mm in the control group and 3.05 (±1.97) in the H and N cancer patients. There was a statistically significant difference between the groups in terms of the mean radial displacement (p = 0.03). In addition, the mean radial displacement increased with the distance from SB. As for the mean volume differences, there was no statistical significance between the two groups. This study suggests that a more generous radial margin should be applied to the lower part of the neck LN for better clinical target coverage and dose delivery.

Ipsilateral dislocation of the radial head associated with fracture of distal end of the radius: a case report and review of the literature

Directory of Open Access Journals (Sweden)

Gupta Vinay

2013-06-01

Full Text Available 【Abstract】Dislocation of the radial head in adults is uncommon. A simultaneous dislocation of the radial head and fracture of the ipsilateral distal end of radius with no other associated injuries is extremely rare. As far as we know, such an injury after an unusual mode of injury has been seldom reported in the English literature. We report such a case without any associated injuries or comorbidity. Closed reduction was performed within two hours after injury and results were satisfactory. Immobilisation was continued for 3 weeks. Gradual mobilisation was started after removal of the plaster under the supervision of a physiotherapist. At 6 months’ follow-up, the patient had no residual pain at the elbow with full flexion & extension. Almost full supination with a restriction of last 10 degrees of pronation was achieved. There was no evidence of instability of the elbow. Key words: Radial heads; Dislocations; Radius fractures

Isolated Post-Traumatic Radial Head Dislocation, A Rare and Easily Missed Injury-A Case Report

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V Gupta

2013-03-01

Full Text Available Dislocation of the head of the radius may be either congenital, an isolated injury or more commonly part of a complex injury to the elbow such as the Monteggia fracturedislocation. Isolated traumatic radial head dislocation without associated injuries in children is a rare and easily missed condition. We report such a case in a 7-year-old boy without any associated injuries or co-morbid conditions. Initially the diagnosis was missed, and 6 weeks later open reduction was performed with annular ligament reconstruction surgery. At the one-year follow up, the patient had returned to most normal activities, showing only slight terminal restriction of pronation. We discuss the injury mechanism and management for the Monteggia fracturedislocation and review the available literature.

Impact of hip prosthesis on dose distribution of pelvic radiotherapy

International Nuclear Information System (INIS)

Ren Jiangping; Zhang Songfang; Zhu Qibao; Guo Jianxin; Zha Yuanzi

2011-01-01

Objective: To study the scattering effect of Co-Cr-Mo hip prosthesis which was high Z material for patients undergoing pelvic irradiation. Methods: The hip prosthesis was set in water phantom (30 cm x 30 cm x 30 cm), determining points were chosen on the entrance side of both 6 MV and 10 MV beams at the distance of 0.5 cm, 1.0 cm, 2.0 cm to the hip prosthesis, and also on the exit side of both 6 MV and 10 MV beams at the distance of 3.0 cm, 5.0 cm, 7.0 cm to the hip prostheses. Dose behind the hip prosthesis at depths of 5.0 cm and 10.0 cm for 6 MV and 10 MV beams are also measured. Results: The dose deviation on the beams' entrance side is between 0 to 5.0%, the backscatter effect was more obviously with the higher energy beam. The dose deviation on the beams' exit side was between 21.6%-30.8%. With the same field size and depth, dose deviation becomes smaller when the beam energy was higher; while with the same energy and depth, dose deviation becomes smaller when the field size was bigger. Dose profiles behind the head of the hip prosthesis indicate obvious attenuation of the beam. Conclusions: Beam arrangements that avoid the prosthesis should be considered first or we should at least reduce the weight of the beam that pass through the prosthesis. (authors)

Humeral head size in shoulder arthroplasty

DEFF Research Database (Denmark)

Vaesel, M T; Olsen, Bo Sanderhoff; Søjbjerg, Jens Ole

1998-01-01

Changes in kinematics after hemiarthroplasty of the glenohumeral joint were investigated in nine cadaveric specimens. During experiments the influence of the humeral head size on glenohumeral kinematics was evaluated. A modular prosthesis with five different head sizes and press-fit stems was use...

Wear-testing of a temporomandibular joint prosthesis : UHMWPE and PTFE against a metal ball, in water and in serum

NARCIS (Netherlands)

Van Loon, JP; Verkerke, GJ; de Bont, LGM; Liem, RSB

For a temporomandibular joint prosthesis, an estimation of the wear rate was needed, prior to patient application. Therefore, we determined the in vitro wear rate of the ball-socket articulation of this prosthesis, consisting of a metal head and an ultra-high molecular weight polyethylene (UHMWPE)

Cross-axis adaptation improves 3D vestibulo-ocular reflex alignment during chronic stimulation via a head-mounted multichannel vestibular prosthesis

Science.gov (United States)

Dai, Chenkai; Fridman, Gene Y.; Chiang, Bryce; Davidovics, Natan; Melvin, Thuy-Anh; Cullen, Kathleen E.; Della Santina, Charles C.

2012-01-01

By sensing three-dimensional (3D) head rotation and electrically stimulating the three ampullary branches of a vestibular nerve to encode head angular velocity, a multichannel vestibular prosthesis (MVP) can restore vestibular sensation to individuals disabled by loss of vestibular hair cell function. However, current spread to afferent fibers innervating non-targeted canals and otolith endorgans can distort the vestibular nerve activation pattern, causing misalignment between the perceived and actual axis of head rotation. We hypothesized that over time, central neural mechanisms can adapt to correct this misalignment. To test this, we rendered five chinchillas vestibular-deficient via bilateral gentamicin treatment and unilaterally implanted them with a head mounted MVP. Comparison of 3D angular vestibulo-ocular reflex (aVOR) responses during 2 Hz, 50°/s peak horizontal sinusoidal head rotations in darkness on the first, third and seventh days of continual MVP use revealed that eye responses about the intended axis remained stable (at about 70% of the normal gain) while misalignment improved significantly by the end of one week of prosthetic stimulation. A comparable time course of improvement was also observed for head rotations about the other two semicircular canal axes and at every stimulus frequency examined (0.2–5 Hz). In addition, the extent of disconjugacy between the two eyes progressively improved during the same time window. These results indicate that the central nervous system rapidly adapts to multichannel prosthetic vestibular stimulation to markedly improve 3D aVOR alignment within the first week after activation. Similar adaptive improvements are likely to occur in other species, including humans. PMID:21374081

99m technetium-MDP bone scintigraphy in evaluation of painful joint prosthesis

International Nuclear Information System (INIS)

Milosevic, D.; Jaukovic, M.; Jaukovic, Lj.; Ajdinovic, B.

2004-01-01

In addition of clinical evaluation and x-ray radiography, the diagnosis of a loose joint prosthesis is often made by nuclear medicine imaging techniques. Differentiation between loosening and infected prosthesis is important for better treatment of those patients. Aim: The aim of this study was to reevaluate the scintigraphic patterns in patients with painful hip of knee arthroplasty. Material and Method: From 1996. to 2003. forty patients aged 49-78 years were referred for evaluation of possible loosening/infection joint prosthesis: 36 pts with 39 total/ partial hip prosthesis, 1 pt with knee prosthesis and 3 pts with history of previously extracted hip prosthesis due to infection. Whole body acquisition had been performed with a single head gamma camera three hours after the injection of 740 MBq 99m Tc-MDP. Scans were classified as: positive for loosening if abnormal uptake was shown at the tip of the prosthesis; positive for infection if diffuse abnormal uptake was shown around the implant; negative and indeterminate scans. Scintigraphic findings were compared to clinical follow up, histology or cultures. Results: Positive findings were found in 17 bone scans strongly suggesting loosening in 10 cases, infection of prosthesis in 4 cases and both loosening/infection in 3 cases. Bone scintigraphy was normal in 11pts. Scans of three pts with previously extracted hip prosthesis and scheduled for reimplatation, showed inhomogeneously and mildly increased uptake in femur. Most of scans classified as indeterminate (n=12) showed slightly increased tracer uptake in region of acetabular roof, greater or lesser tho chanter, suggesting bone remodeling due to the presence of implant, rather than loosening. Conclusion: 99m Tc-MDP bone scintigraphy had a significant role in assessing the painful joint prosthesis. Complementary diagnostic procedures should be considered in indeterminate scintiscans. (authors)

A Graphic Overlay Method for Selection of Osteotomy Site in Chronic Radial Head Dislocation: An Evaluation of 3D-printed Bone Models.

Science.gov (United States)

Kim, Hui Taek; Ahn, Tae Young; Jang, Jae Hoon; Kim, Kang Hee; Lee, Sung Jae; Jung, Duk Young

2017-03-01

Three-dimensional (3D) computed tomography imaging is now being used to generate 3D models for planning orthopaedic surgery, but the process remains time consuming and expensive. For chronic radial head dislocation, we have designed a graphic overlay approach that employs selected 3D computer images and widely available software to simplify the process of osteotomy site selection. We studied 5 patients (2 traumatic and 3 congenital) with unilateral radial head dislocation. These patients were treated with surgery based on traditional radiographs, but they also had full sets of 3D CT imaging done both before and after their surgery: these 3D CT images form the basis for this study. From the 3D CT images, each patient generated 3 sets of 3D-printed bone models: 2 copies of the preoperative condition, and 1 copy of the postoperative condition. One set of the preoperative models was then actually osteotomized and fixed in the manner suggested by our graphic technique. Arcs of rotation of the 3 sets of 3D-printed bone models were then compared. Arcs of rotation of the 3 groups of bone models were significantly different, with the models osteotomized accordingly to our graphic technique having the widest arcs. For chronic radial head dislocation, our graphic overlay approach simplifies the selection of the osteotomy site(s). Three-dimensional-printed bone models suggest that this approach could improve range of motion of the forearm in actual surgical practice. Level IV-therapeutic study.

Progress Toward Development of a Multichannel Vestibular Prosthesis for Treatment of Bilateral Vestibular Deficiency

Science.gov (United States)

FRIDMAN, GENE Y.; DELLA SANTINA, CHARLES C.

2014-01-01

This article reviews vestibular pathology and the requirements and progress made in the design and construction of a vestibular prosthesis. Bilateral loss of vestibular sensation is disabling. When vestibular hair cells are injured by ototoxic medications or other insults to the labyrinth, the resulting loss of sensory input disrupts vestibulo-ocular reflexes (VORs) and vestibulo-spinal reflexes that normally stabilize the eyes and body. Affected individuals suffer poor vision during head movement, postural instability, chronic disequilibrium, and cognitive distraction. Although most individuals with residual sensation compensate for their loss over time, others fail to do so and have no adequate treatment options. A vestibular prosthesis analogous to cochlear implants but designed to modulate vestibular nerve activity during head movement should improve quality of life for these chronically dizzy individuals. We describe the impact of bilateral loss of vestibular sensation, animal studies supporting feasibility of prosthetic vestibular stimulation, the current status of multichannel vestibular sensory replacement prosthesis development, and challenges to successfully realizing this approach in clinical practice. In bilaterally vestibular-deficient rodents and rhesus monkeys, the Johns Hopkins multichannel vestibular prosthesis (MVP) partially restores the three-dimensional (3D) VOR for head rotations about any axis. Attempts at prosthetic vestibular stimulation of humans have not yet included the 3D eye movement assays necessary to accurately evaluate VOR alignment, but these initial forays have revealed responses that are otherwise comparable to observations in animals. Current efforts now focus on refining electrode design and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimizing stimulus protocols to improve dynamic range and reduce excitation–inhibition asymmetry, and adapting laboratory MVP prototypes into devices

Progress toward development of a multichannel vestibular prosthesis for treatment of bilateral vestibular deficiency.

Science.gov (United States)

Fridman, Gene Y; Della Santina, Charles C

2012-11-01

This article reviews vestibular pathology and the requirements and progress made in the design and construction of a vestibular prosthesis. Bilateral loss of vestibular sensation is disabling. When vestibular hair cells are injured by ototoxic medications or other insults to the labyrinth, the resulting loss of sensory input disrupts vestibulo-ocular reflexes (VORs) and vestibulo-spinal reflexes that normally stabilize the eyes and body. Affected individuals suffer poor vision during head movement, postural instability, chronic disequilibrium, and cognitive distraction. Although most individuals with residual sensation compensate for their loss over time, others fail to do so and have no adequate treatment options. A vestibular prosthesis analogous to cochlear implants but designed to modulate vestibular nerve activity during head movement should improve quality of life for these chronically dizzy individuals. We describe the impact of bilateral loss of vestibular sensation, animal studies supporting feasibility of prosthetic vestibular stimulation, the current status of multichannel vestibular sensory replacement prosthesis development, and challenges to successfully realizing this approach in clinical practice. In bilaterally vestibular-deficient rodents and rhesus monkeys, the Johns Hopkins multichannel vestibular prosthesis (MVP) partially restores the three-dimensional (3D) VOR for head rotations about any axis. Attempts at prosthetic vestibular stimulation of humans have not yet included the 3D eye movement assays necessary to accurately evaluate VOR alignment, but these initial forays have revealed responses that are otherwise comparable to observations in animals. Current efforts now focus on refining electrode design and surgical technique to enhance stimulus selectivity and preserve cochlear function, optimizing stimulus protocols to improve dynamic range and reduce excitation-inhibition asymmetry, and adapting laboratory MVP prototypes into devices

Stability of radial head and neck fractures: a biomechanical study of six fixation constructs with consideration of three locking plates.

Science.gov (United States)

Burkhart, Klaus Josef; Mueller, Lars P; Krezdorn, David; Appelmann, Philipp; Prommersberger, Karl J; Sternstein, Werner; Rommens, Pol M

2007-12-01

Open reduction and internal fixation of radial neck fractures can lead to secondary loss of reduction and nonunion due to insufficient stability. Nevertheless, there are only a few biomechanical studies about the stability achieved by different osteosynthesis constructs. Forty-eight formalin-fixed, human proximal radii were divided into 6 groups according to their bone density (measured by dual-energy x-ray absorptiometry). A 2.7-mm gap osteotomy was performed to simulate an unstable radial neck fracture, which was fixed with 3 nonlocking implants: a 2.4-mm T plate, a 2.4-mm blade plate, and 2.0-mm crossed screws, and 3 locking plates: a 2.0-mm LCP T plate, a 2.0-mm 6x2 grid plate, and a 2.0-mm radial head plate. Implants were tested under axial (N/mm) and torsional (Ncm/ degrees ) loads with a servohydraulic materials testing machine. The radial head plate was significantly stiffer than all other implants under axial as well as under torsional loads, with values of 36 N/mm and 13 Ncm/ degrees . The second-stiffest implant was the blade plate, with values of 20 N/mm and 6 Ncm/ degrees . The weakest implants were the 2.0-mm LCP, with values of 6 N/mm and 2 Ncm/ degrees , and the 2.0-mm crossed screws, with values of 18 N/mm and 2 Ncm/ degrees . The 2.4-mm T plate, with values of 14 N/mm and 4 Ncm/ degrees , and the 2.0-mm grid plate, with values of 8 N/mm and 4 Ncm/ degrees came to lie in the midfield. The 2.0-mm angle-stable plates-depending on their design-allow fixation with comparable or even higher stability than the bulky 2.4-mm nonlocking implants and 2.0-mm crossed screws.

Steel syndrome: dislocated hips and radial heads, carpal coalition, scoliosis, short stature, and characteristic facial features.

Science.gov (United States)

Flynn, John M; Ramirez, Norman; Betz, Randal; Mulcahey, Mary Jane; Pino, Franz; Herrera-Soto, Jose A; Carlo, Simon; Cornier, Alberto S

2010-01-01

A syndrome of children with short stature, bilateral hip dislocations, radial head dislocations, carpal coalitions, scoliosis, and cavus feet in Puerto Rican children, was reported by Steel et al in 1993. The syndrome was described as a unique entity with dismal results after conventional treatment of dislocated hips. The purpose of this study is to reevaluate this patient population with a longer follow-up and delineate the clinical and radiologic features, treatment outcomes, and the genetic characteristics. This is a retrospective cohort study of 32 patients in whom we evaluated the clinical, imaging data, and genetic characteristics. We compare the findings and quality of life in patients with this syndrome who have had attempts at reduction of the hips versus those who did not have the treatment. Congenital hip dislocations were present in 100% of the patients. There was no attempt at reduction in 39% (25/64) of the hips. In the remaining 61% (39/64), the hips were treated with a variety of modalities fraught with complications. Of those treated, 85% (33/39) remain dislocated, the rest of the hips continue subluxated with acetabular dysplasia and pain. The group of hips that were not treated reported fewer complaints and limitation in daily activities compared with the hips that had attempts at reduction. Steel syndrome is a distinct clinical entity characterized by short stature, bilateral hip and radial head dislocation, carpal coalition, scoliosis, cavus feet, and characteristic facial features with dismal results for attempts at reduction of the hips. Prognostic Study Level II.

Total Ossicular Replacement Prosthesis: A New Fat Interposition Technique

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Issam Saliba

2018-01-01

Full Text Available Objective: To compare audiometric results between the standard total ossicular replacement prosthesis (TORP-S and a new fat interposition total ossicular replacement prosthesis (TORP-F in pediatric and adult patients and to assess the complication and the undesirable outcome. Study design: This is a retrospective study. Methods: This study included 104 patients who had undergone titanium implants with TORP-F and 54 patients who had undergone the procedure with TORP-S between 2008 and 2013 in our tertiary care centers. The new technique consists of interposing a fat graft between the 4 legs of the universal titanium prosthesis (Medtronic Xomed Inc, Jacksonville, FL, USA to provide a more stable TORP in the ovale window niche. Normally, this prosthesis is designed to fit on the stapes’ head as a partial ossicular replacement prosthesis. Results: The postoperative air-bone gap less than 25 dB for the combined cohort was 69.2% and 41.7% for the TORP-F and the TORP-S groups, respectively. The mean follow-up was 17 months postoperatively. By stratifying data, the pediatric cohort shows 56.5% in the TORP-F group (n = 52 compared with 40% in the TORP-S group (n = 29. However, the adult cohort shows 79.3% in the TORP-F group (n = 52 compared with 43.75% in the TORP-S group (n = 25. These improvements in hearing were statistically significant. There were no statistically significant differences in the speech discrimination scores. The only undesirable outcome that was statistically different between the 2 groups was the prosthesis displacement: 7% in the TORP-F group compared with 19% in the TORP-S group ( P  = .03. Conclusions: The interposition of a fat graft between the legs of the titanium implants (TORP-F provides superior hearing results compared with a standard procedure (TORP-S in pediatric and adult populations because of its better stability in the oval window niche.

Total Ossicular Replacement Prosthesis: A New Fat Interposition Technique.

Science.gov (United States)

Saliba, Issam; Sabbah, Valérie; Poirier, Jackie Bibeau

2018-01-01

To compare audiometric results between the standard total ossicular replacement prosthesis (TORP-S) and a new fat interposition total ossicular replacement prosthesis (TORP-F) in pediatric and adult patients and to assess the complication and the undesirable outcome. This is a retrospective study. This study included 104 patients who had undergone titanium implants with TORP-F and 54 patients who had undergone the procedure with TORP-S between 2008 and 2013 in our tertiary care centers. The new technique consists of interposing a fat graft between the 4 legs of the universal titanium prosthesis (Medtronic Xomed Inc, Jacksonville, FL, USA) to provide a more stable TORP in the ovale window niche. Normally, this prosthesis is designed to fit on the stapes' head as a partial ossicular replacement prosthesis. The postoperative air-bone gap less than 25 dB for the combined cohort was 69.2% and 41.7% for the TORP-F and the TORP-S groups, respectively. The mean follow-up was 17 months postoperatively. By stratifying data, the pediatric cohort shows 56.5% in the TORP-F group (n = 52) compared with 40% in the TORP-S group (n = 29). However, the adult cohort shows 79.3% in the TORP-F group (n = 52) compared with 43.75% in the TORP-S group (n = 25). These improvements in hearing were statistically significant. There were no statistically significant differences in the speech discrimination scores. The only undesirable outcome that was statistically different between the 2 groups was the prosthesis displacement: 7% in the TORP-F group compared with 19% in the TORP-S group ( P  = .03). The interposition of a fat graft between the legs of the titanium implants (TORP-F) provides superior hearing results compared with a standard procedure (TORP-S) in pediatric and adult populations because of its better stability in the oval window niche.

Robotic lower limb prosthesis design through simultaneous computer optimizations of human and prosthesis costs

Science.gov (United States)

Handford, Matthew L.; Srinivasan, Manoj

2016-02-01

Robotic lower limb prostheses can improve the quality of life for amputees. Development of such devices, currently dominated by long prototyping periods, could be sped up by predictive simulations. In contrast to some amputee simulations which track experimentally determined non-amputee walking kinematics, here, we explicitly model the human-prosthesis interaction to produce a prediction of the user’s walking kinematics. We obtain simulations of an amputee using an ankle-foot prosthesis by simultaneously optimizing human movements and prosthesis actuation, minimizing a weighted sum of human metabolic and prosthesis costs. The resulting Pareto optimal solutions predict that increasing prosthesis energy cost, decreasing prosthesis mass, and allowing asymmetric gaits all decrease human metabolic rate for a given speed and alter human kinematics. The metabolic rates increase monotonically with speed. Remarkably, by performing an analogous optimization for a non-amputee human, we predict that an amputee walking with an appropriately optimized robotic prosthesis can have a lower metabolic cost - even lower than assuming that the non-amputee’s ankle torques are cost-free.

Total hip arthroplasty using a short-stem prosthesis: restoration of hip anatomy.

Science.gov (United States)

Amenabar, Tomas; Marimuthu, Kanniraj; Hawdon, Gabrielle; Gildone, Alessandro; McMahon, Stephen

2015-04-01

To evaluate hip parameters such as vertical centre of rotation (VCR), horizontal centre of rotation (HCR), femoral offset, and leg length after total hip arthroplasty (THA) using the Nanos short-stem prosthesis. Medical records of 73 men and 74 women aged 25 to 92 (mean, 63) years who underwent THA using the Nanos short-stem prosthesis by a single surgeon were reviewed. Prior to the surgery, the optimal cup and stem size, head length, and level of the neck osteotomy were determined using radiographs. Intra-operatively, the leg length and femoral offset were checked, and the level of neck resection and head length were adjusted. VCR, HCR, femoral offset, and leg length of the operated and contralateral sides were compared. Functional outcomes were assessed using the Harris Hip Score (HHS). Compared with the normal contralateral hips, the operated hips had a mean increase of 0.4 mm in VCR (p=0.032), a mean decrease of 1.4 mm in HCR (p=0.027), a mean increase of 0.6 mm in femoral offset (p=0.043), and a mean increase of 0.36 mm in leg length (p=0.035). For these respective parameters, the difference between the normal contralateral side and the operated side was within 5 mm in 89%, 80%, 71%, and 96% of patients. The HHS improved from a mean of 53 to 91 at one year (pNanos short-stem prosthesis enabled restoration of hip anatomy (VCR, HCR, femoral offset, and leg length).

Elbow arthroplasty in perspective

NARCIS (Netherlands)

Heijink, A.

2017-01-01

This thesis focuses on the effect of biomechanical aspects of prosthesis design and outcome after radial head and total elbow arthroplasty. First, we examine the available evidence regarding the role of several unfavorable biomechanical conditions about the elbow in the development of

Free radial forearm flap versatility for the head and neck and lower extremity

International Nuclear Information System (INIS)

Chicarilli, Z.N.; Ariyan, S.; Cuono, C.B.

1986-01-01

Microsurgical techniques have developed numerous territories suitable for free tissue transfer. However, the demand for thin cutaneous resurfacing limits the choice of flaps available to the reconstructive microsurgeon. The radial forearm flap is a thin, axial, fasciocutaneous flap, offering pliable cutaneous resurfacing, with or without sensation. We have used 15 flaps to reconstruct defects in the head and neck and lower extremity resulting from burns, blunt and avulsive trauma, radiation necrosis, and tumor ablation. Two flaps (15 percent) developed venous congestion and were salvaged by reoperation. One retrograde flap (7.5 percent) developed partial necrosis from arterial insufficiency. Neural re-innervation was successful in two out of three patients in whom it was attempted. Two patients (15%) sustained minor donor site skin graft loss that healed secondarily. In our series of predominantly older patients the donor sites have been relatively inconspicuous at one year follow-up. A functional restoration was achieved in all patients

Development and performance of a new prosthesis system using ultrasonic sensor for wrist movements: a preliminary study

Science.gov (United States)

2014-01-01

Background The design and performance of a new development prosthesis system known as biomechatronics wrist prosthesis is presented in this paper. The prosthesis system was implemented by replacing the Bowden tension cable of body powered prosthesis system using two ultrasonic sensors, two servo motors and microcontroller inside the prosthesis hand for transradial user. Methods The system components and hand prototypes involve the anthropometry, CAD design and prototyping, biomechatronics engineering together with the prosthetics. The modeler construction of the system develop allows the ultrasonic sensors that are placed on the shoulder to generate the wrist movement of the prosthesis. The kinematics of wrist movement, which are the pronation/supination and flexion/extension were tested using the motion analysis and general motion of human hand were compared. The study also evaluated the require degree of detection for the input of the ultrasonic sensor to generate the wrist movements. Results The values collected by the vicon motion analysis for biomechatronics prosthesis system were reliable to do the common tasks in daily life. The degree of the head needed to bend to give the full input wave was about 45° - 55° of rotation or about 14 cm – 16 cm. The biomechatronics wrist prosthesis gave higher degree of rotation to do the daily tasks but did not achieve the maximum degree of rotation. Conclusion The new development of using sensor and actuator in generating the wrist movements will be interesting for used list in medicine, robotics technology, rehabilitations, prosthetics and orthotics. PMID:24755242

The Angelchik prosthesis

International Nuclear Information System (INIS)

Fargnoli, R.; Bozza, A.; Magnoli, A.; Villari, N.; Pernice, L.M.; Andreoli, F.; Lombardi, P.

1989-01-01

The Angelchik prosthesis is used in the surgical treatment of gastroesophageal reflux. Operated patients are preliminary examined with imaging techniques, but manometric and acidometric techniques are also used. Although the conventional esophagogram still maintains its diagnostic significance, Computed Tomography (CT) has become the first-choice imaging modality. CT allows the correct evaluation of both the state of the prosthesis and its relationship to the esophagus and gastric fundus. The possible postoperative complications following an incorrect placement of the prosthesis can be accurately diagnosed too. The authors report their experience in the study of 5 patients examined with both conventional radiology and CT

Fracturing of revision of a cobalt-chrome femoral head after fracturing of a ceramic femoral head, with diffuse metallosis. Case report

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Pedro Miguel Dantas Costa Marques

2013-04-01

Full Text Available We presente a case of a fracture of a cobalt-chrome femoral head after revision of a hip total prosthesis with ceramic femoral head fracture. During surgery we found the cobalt-chrome femoral head fracture, wear of the polyethylene and massive metallosis in muscular and cartilaginous tissue. Both femoral stem and acetabular cup were stable and without apparent wearing. After surgical debridement, we promoted the substitution of the femoral head and the acetabular polyethylene by similar ones. After 12 months of follow-up, the patient has no pain complaints, function limit or systemic signs associated with malign metallosis

Three-Dimensional Printed Prosthesis for Repair of Superior Canal Dehiscence.

Science.gov (United States)

Kozin, Elliott D; Remenschneider, Aaron K; Cheng, Song; Nakajima, Hideko Heidi; Lee, Daniel J

2015-10-01

Outcomes following repair of superior canal dehiscence (SCD) are variable, and surgery carries a risk of persistent or recurrent SCD symptoms, as well as a risk of hearing loss and vestibulopathy. Poor outcomes may occur from inadequate repair of the SCD or mechanical insult to the membranous labyrinth. Repair of SCD using a customized, fixed-length prosthesis may address current operative limitations and improve surgical outcomes. We aim to 3-dimensionally print customized prostheses to resurface or occlude bony SCD defects. Dehiscences were created along the arcuate eminence of superior semicircular canals in cadaveric temporal bones. Prostheses were designed and created using computed tomography and a 3-dimensional printer. The prostheses occupied the superior semicircular canal defect, reflected in postrepair computed tomography scans. This novel approach to SCD repair could have advantages over current techniques. Refinement of prosthesis design and materials will be important if this approach is translated into clinical use. © American Academy of Otolaryngology-Head and Neck Surgery Foundation 2015.

THR Simulator – the software for generating radiographs of THR prosthesis

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Hou Sheng-Mou

2009-01-01

Full Text Available Abstract Background Measuring the orientation of acetabular cup after total hip arthroplasty is important for prognosis. The verification of these measurement methods will be easier and more feasible if we can synthesize prosthesis radiographs in each simulated condition. One reported method used an expensive mechanical device with an indeterminable precision. We thus develop a program, THR Simulator, to directly synthesize digital radiographs of prostheses for further analysis. Under Windows platform and using Borland C++ Builder programming tool, we developed the THR Simulator. We first built a mathematical model of acetabulum and femoral head. The data of the real dimension of prosthesis was adopted to generate the radiograph of hip prosthesis. Then with the ray tracing algorithm, we calculated the thickness each X-ray beam passed, and then transformed to grey scale by mapping function which was derived by fitting the exponential function from the phantom image. Finally we could generate a simulated radiograph for further analysis. Results Using THR Simulator, the users can incorporate many parameters together for radiograph synthesis. These parameters include thickness, film size, tube distance, film distance, anteversion, abduction, upper wear, medial wear, and posterior wear. These parameters are adequate for any radiographic measurement research. This THR Simulator has been used in two studies, and the errors are within 2° for anteversion and 0.2 mm for wearing measurement. Conclusion We design a program, THR Simulator that can synthesize prosthesis radiographs. Such a program can be applied in future studies for further analysis and validation of measurement of various parameters of pelvis after total hip arthroplasty.

The Talar Body Prosthesis: Results at Ten to Thirty-six Years of Follow-up.

Science.gov (United States)

Harnroongroj, Thos; Harnroongroj, Thossart

2014-07-16

Satisfactory results of implantation of the talar body prosthesis were reported in 1997, although some complications associated with the initial design were noted. The present study evaluated outcomes of treatment with a modified talar body prosthesis. Of the thirty-six talar body prostheses implanted with use of a transmalleolar surgical approach from 1974 to 2011, thirty-three were available for follow-up at ten to thirty-six years or had failed prior to that time. The indication for implantation had been osteonecrosis in twenty-three patients, a comminuted talar fracture in eight, and a talar body tumor in two. Twenty-eight of the thirty-three prostheses were still in place at the time of final follow-up and five had failed prior to five years. The duration of follow-up was ten to twenty years in eight patients, twenty to thirty years in eleven, and thirty to thirty-six years in nine. The AOFAS (American Orthopaedic Foot & Ankle Society) ankle-hindfoot score did not differ significantly among these three groups. Patients over sixty-five years of age with underlying disease that impeded walking ability had lower AOFAS scores. Early prosthesis failure occurred as a result of size mismatch in two patients, tumor recurrence in one, infection in one, and osteonecrosis of the talar head and neck in one. These failures, which occurred at eight to fifty-seven months, were treated with tibiotalar arthrodesis in three patients, prosthesis revision in one, and below-the-knee amputation in one. Although early prosthesis failure may occur, survival of the talar body prosthesis can provide satisfactory ankle and foot function. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

Nasal prosthesis rehabilitation: a case report

DEFF Research Database (Denmark)

Jain, Sumeet; Maru, Kavita; Shukla, Jyotsana

2011-01-01

Facial defects resulting from neoplasm, congenital malformation or trauma can be restored with facial prosthesis using different materials and retention methods to achieve life-like look and function. A nasal prosthesis can re-establish esthetic form and anatomic contours for mid-facial defects...... the non-surgical rehabilitation, with polymethyl meth-acrylate resin, nasal prosthesis for a patient who received partial rhinectomy as a result of squamous cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of the patient with a mechanical retained design using...

Anomalous Medial Branch of Radial Artery: A Rare Variant

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Surbhi Wadhwa

2016-10-01

Full Text Available Radial artery is an important consistent vessel of the upper limb. It is a useful vascular access site for coronary procedures and its reliable anatomy has resulted in an elevation of radial forearm flaps for reconstructive surgeries of head and neck. Technical failures, in both the procedures, are mainly due to anatomical variations, such as radial loops, ectopic radial arteries or tortuosity in the vessel. We present a rare and a unique anomalous medial branch of the radial artery spiraling around the flexor carpi radialis muscle in the forearm with a high rising superficial palmar branch of radial artery. Developmentally it probably is a remanent of the normal pattern of capillary vessel maintenance and regression. Such a case is of importance for reconstructive surgeons and coronary interventionists, especially in view of its unique medial and deep course.

A Low-Power ASIC Signal Processor for a Vestibular Prosthesis.

Science.gov (United States)

Töreyin, Hakan; Bhatti, Pamela T

2016-06-01

A low-power ASIC signal processor for a vestibular prosthesis (VP) is reported. Fabricated with TI 0.35 μm CMOS technology and designed to interface with implanted inertial sensors, the digitally assisted analog signal processor operates extensively in the CMOS subthreshold region. During its operation the ASIC encodes head motion signals captured by the inertial sensors as electrical pulses ultimately targeted for in-vivo stimulation of vestibular nerve fibers. To achieve this, the ASIC implements a coordinate system transformation to correct for misalignment between natural sensors and implanted inertial sensors. It also mimics the frequency response characteristics and frequency encoding mappings of angular and linear head motions observed at the peripheral sense organs, semicircular canals and otolith. Overall the design occupies an area of 6.22 mm (2) and consumes 1.24 mW when supplied with ± 1.6 V.

Mechanical analysis of ceramic heat being part of hip prosthesis with presence of cracks

International Nuclear Information System (INIS)

Ravagli, E.

1995-03-01

This report still pursues the aim of carrying out a systematic mechanical analysis of a ceramic heat being part of a modular hig prosthesis, in order to characterize it exhaustively, i. e. to assess its performances and some of its main specifications. A mechanical analysis of a second case is carried out here, the presence of head cracks being taken into account. The evaluations made lead to the conclusion that the head should not show cracks bigger than 100 mm. This study is performed in the frame of the STRIDE-CETMA project, which is aimed at founding and developing a centre for technologically advanced materials in Brindisi technology park (Italy)

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

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Firat Seyfettinoglu

2016-07-01

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

Implant-Retained Auricular Prosthesis: A Case Report

OpenAIRE

Ozturk, A. Nilgun; Usumez, Aslihan; Tosun, Zekeriya

2010-01-01

Extraoral implant retained prosthesis have been proven to be a predictable treatment option for maxillofacial rehabilitation. This case report describes the clinical and laboratory procedures for fabricating an auricular prosthesis. In this case report, an auricular prosthesis was fabricated for a patient who lost the left and right external ear in an electrical burn. Extraoral implants and bar-and-clip retention for the proper connection of the auricular prosthesis to implant were used. This...

Permanent Quadriplegia Following Replacement of Voice Prosthesis.

Science.gov (United States)

Ozturk, Kayhan; Erdur, Omer; Kibar, Ertugrul

2016-11-01

The authors presented a patient with quadriplegia caused by cervical spine abscess following voice prosthesis replacement. The authors present the first reported permanent quadriplegia patient caused by voice prosthesis replacement. The authors wanted to emphasize that life-threatening complications may be faced during the replacement of voice prosthesis. Care should be taken during the replacement of voice prosthesis and if some problems have been faced during the procedure patients must be followed closely.

Laser-assisted fixation of a nitinol stapes prosthesis.

Science.gov (United States)

Schrötzlmair, Florian; Suchan, Fabian; Pongratz, Thomas; Krause, Eike; Müller, Joachim; Sroka, Ronald

2018-02-01

Otosclerosis is an inner ear bone disease characterized by fixation of the stapes and consequently progressive hearing loss. One treatment option is the surgical replacement of the stapes by a prosthesis. When so called "smart materials" like nitinol are used, prosthesis fixation can be performed using a laser without manual crimping on the incus. However, specific laser-prosthesis interactions have not been described yet. The aim of the present study was to elucidate the thermo-mechanical properties of the NiTiBOND® prosthesis as a basis for handling instructions for laser-assisted prosthesis fixation. Closure of the NiTiBOND® prosthesis was induced ex vivo by either a diode laser emitting at λ = 940 nm or a CO 2 laser (λ = 10,600 nm). Total energy for closure was determined. Suitable laser parameters (pulse duration, power per pulse, distance between tip of the laser fiber and prosthesis) were assessed. Specific laser-prosthesis interactions were recorded. Especially the diode laser was found to be an appropriate energy source. A total energy deposit of 60 mJ by pulses in near contact application was found to be sufficient for prosthesis closure ex vivo. Energy should be transmitted through a laser fiber equipollent to the prosthesis band diameter. Specific deformation characteristics due to the zonal prosthesis composition have to be taken into account. NiTiBOND® stapes prosthesis can be closed by very little energy when appropriate energy sources like diode lasers are used, suggesting a relatively safe application in vivo. Lasers Surg. Med. 50:153-157, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Patients with hip prosthesis: radiotherapy treatment planning considerations

International Nuclear Information System (INIS)

Ganesh, K.M.; Supe, Sanjay S.

2000-01-01

The number of patients with hip prosthesis undergoing radiotherapy for pelvic cancer worldwide is increasing. This might be of importance depending on the materials in the prosthesis and whether any of the treatment fields are involved in the prosthesis. Radiotherapy planning involving the pelvic region of patients having total hip prosthesis has been found to be difficult due to the effect of the prosthesis on the dose distribution. This review is intended to project dosimetric considerations and possible solutions to this uncommon problem

21 CFR 872.3960 - Mandibular condyle prosthesis.

Science.gov (United States)

2010-04-01

... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3960 Mandibular condyle prosthesis. (a) Identification. A mandibular condyle prosthesis is a device that is intended to be implanted in the human jaw to... requirement for premarket approval for any mandibular condyle prosthesis intended to be implanted in the human...

Dosimetry of a silicone breast prosthesis

International Nuclear Information System (INIS)

McGinley, P.H.; Powell, W.R.; Bostwick, J.

1980-01-01

Dose measurements were conducted in a phantom which simulates breast tissue and in another phantom which simulates a breast containing a silicone prosthesis. No detectable difference was found when the irradiations were carried out with tangential beams of 60 Co radiation. The degree of backscatter and absorption of radiation by the prosthesis and phantom were also similar. A slight decrease in dose of approximately 8% was found at the interface between the prosthesis and muscle-equivalent material

Bilateral radial neck fractures – A Case Report

Directory of Open Access Journals (Sweden)

ABY Ng

2007-11-01

Full Text Available Radial head and neck fractures are the most frequently seen elbow fractures. The usual cause of this injury is a fall onto an outstretched hand with a partly flexed elbow. We report here an unusual case of bilateral non-displaced radial neck fractures in a patient who presented with complaints of pain in both elbows following a simple fall. This case highlights the need for a high index of suspicion in the diagnosis of multiple injuries, no matter how `trivial` the mechanism of injury.

Duocentric® reversed shoulder prosthesis and Personal Fit® templates: innovative strategies to optimize prosthesis positioning and prevent scapular notching.

Science.gov (United States)

Trouilloud, P; Gonzalvez, M; Martz, P; Charles, H; Handelberg, F; Nyffeler, R W; Baulot, E

2014-05-01

We describe our experience with a new system of patient-specific template called Personal Fit(®), which is unique in shoulder surgery and used in combination with Duocentric(®) prosthesis. The reverse prosthesis's concept is the invention of Paul Grammont, developed with Grammont's team of Dijon University as from 1981, which led to the first reversed total shoulder prosthesis called Trumpet in 1985. The Duocentric(®) prosthesis developed in 2001 is the third-generation prosthesis, coming from the Trumpet and the second-generation prosthesis Delta(®) (DePuy). This prosthesis provides a novel solution to the notching problem with an inferior overhang integrated onto the glenoid baseplate. Personal Fit(®) system is based on reconstructing the shoulder joint bones in three dimensions using CT scan data, placing a landmark on the scapula and locating points on the glenoid and humerus. That will be used as a reference for the patient-specific templates. We study the glenoid position planned with Personal Fit(®) software relative to native glenoid position in 30 cases. On average, the difference between the planned retroversion (or anteversion in one case) and native retroversion was 8.6°.

A Medical Wireless Measurement System for Hip Prosthesis Loosening Detection Based on Vibration Analysis

Directory of Open Access Journals (Sweden)

Sebastian Sauer

2013-01-01

Full Text Available Vibration analysis is a promising approach in order to detect early hip prosthesis loosening, with the potential to extend the range of diagnostic tools currently available in clinical routine. Ongoing research efforts and developments in the area of multi-functional implants, which integrate sensors, wireless power supply, communication and signal processing, provide means to obtain valuable in vivo information otherwise not available. In the current work a medical wireless measurement system is presented, which is integrated in the femoral head of a hip prosthesis. The passive miniaturized system includes a 3-axis acceleration sensor and signal pre-processing based on a lock-in amplifier circuit. Bidirectional data communication and power supply is reached through inductive coupling with an operating frequency of 125 kHz in accordance with the ISO 18000-2 protocol standard. The system allows the acquisition of the acceleration frequency response of the femur-prosthesis system between 500 to 2500 Hz. Applied laboratory measurements with system prototypes on artificial bones and integrated prostheses demonstrate the feasibility of the measurement system approach, clearly showing differences in the vibration behavior due to an implant loosening. In addition a possibility to evaluate the non-linear mechanic system behavior is presented.

Malrotation of the McGhan Style 510 prosthesis.

NARCIS (Netherlands)

Schots, J.M.; Fechner, M.R.; Hoogbergen, M.M.; Tits, H.W.H.J.

2010-01-01

BACKGROUND: Anatomically shaped cohesive silicone breast implants are frequently used in aesthetic and reconstructive surgery. After successful results with the Style 410 prosthesis, McGhan (Natrelle, Allergan) introduced the Style 510 prosthesis. After using this novel prosthesis, the authors

Finger prosthesis: a boon to handicapped.

Science.gov (United States)

Gupta, Ridhima; Kumar, Lakshya; Rao, Jitendra; Singh, Kamleshwar

2013-08-29

This is a clinical case report of a 52-year-old male patient with four partially missing fingers of the left hand. The article describes the clinical and laboratory procedure of making prosthesis with modern silicone material. A wax pattern was fabricated using the right hand of the patient. A special type of wax was formulated to make the pattern so that it can be easily moulded and carved. Intrinsic and extrinsic staining was also performed to match the adjacent skin colour. The patient was given the finger prosthesis and was asked to use a half glove (sports) to mask the junction between the prosthesis and the normal tissue. It also provides additional retention to the artificial fingers. The patient felt his social acceptance improved after wearing the finger prosthesis.

Reactor head shielding apparatus

International Nuclear Information System (INIS)

Schukei, G.E.; Roebelen, G.J.

1992-01-01

This patent describes a nuclear reactor head shielding apparatus for mounting on spaced reactor head lifting members radially inwardly of the head bolts. It comprises a frame of sections for mounting on the lifting members and extending around the top central area of the head, mounting means for so mounting the frame sections, including downwardly projecting members on the frame sections and complementary upwardly open recessed members for fastening to the lifting members for receiving the downwardly projecting members when the frame sections are lowered thereto with lead shielding supported thereby on means for hanging lead shielding on the frame to minimize radiation exposure or personnel working with the head bolts or in the vicinity thereof

21 CFR 878.3800 - External aesthetic restoration prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false External aesthetic restoration prosthesis. 878... External aesthetic restoration prosthesis. (a) Identification. An external aesthetic restoration prosthesis... (general controls). The device is exempt from the premarket notification procedures in subpart E of part...

Rehabilitation of a Patient with an Intra Oral Prosthesis and an Extra Oral Orbital Prosthesis Retained with Magnets

OpenAIRE

Pattanaik, Seema; Wadkar, Aarti P.

2011-01-01

This clinical case report deals with a rehabilitation of a patient with an extensive maxillary and orbital defect using an intra oral prosthesis obturating the maxillary defect and extra oral orbital prosthesis retained with rare-earth magnets for secondary retention; primary retention was derived by snug fit of the prosthesis to underlying and adjacent tissues. The rehabilitation resulted in improved function, esthetics and comfort to the patient thus enabling him to lead a normal life.

Attachment-retained gingival prosthesis for implant-supported fixed dental prosthesis in the maxilla: a clinical report.

Science.gov (United States)

Aparecida de Mattias Sartori, Ivete; Uhlendorf, Yuri; Padovan, Luiz Eduardo Marques; Junior, Paulo Domingos Ribeiro; Melo, Ana Cláudia Moreira; Tiossi, Rodrigo

2014-12-01

The rehabilitation of edentulous maxillae is a complex procedure due to the involvement of esthetic and functional requirements. A trial maxillary denture can be used to identify the need for adequate upper lip support when replacing removable complete dentures by implant-fixed dental prostheses. This clinical report describes the outcome of the rehabilitation of an edentulous atrophic maxilla with unfavorable maxillomandibular relationship and deficient upper lip support. A trial denture was fabricated and used to diagnose the need for a prosthesis capable of restoring the upper lip support. The reduced upper lip support was also confirmed by a lateral cephalogram. The patient was rehabilitated by an implant-fixed dental prosthesis associated with an attachment-retained gingival prosthesis. The case presented shows that when loss of upper lip support is detected and the patient does not wish to undergo further surgical reconstruction procedure, the retention of a gingival prosthesis using a ball attachment is a satisfactory treatment option. © 2014 by the American College of Prosthodontists.

Results of endoprosthetic hip joint replacement with the aluminum ceramic-metal composite prosthesis "Lindenhof".

Science.gov (United States)

Stock, D; Diezemann, E D; Gottstein, J

1980-01-01

The first clinical results of the Lindenhof ceramic-metal composite prosthesis implanted in our hospital in Freiburg are presented. We observed that same favorable early results as the conventional prostheses in a correct position. The implants are incorporated into the bone within 8-12 weeks. The radiographic films show the adaptation of the supporting bone around the ceramic socket. We explain the failures due to our initial lack of technical experience and/or anatomical deformation of the pelvic bone. complications caused by the post-operative treatment during the 12 weeks following surgery did not occur. The combination of a cemented metal femoral component with a ceramic head seems to be a reasonable compromise to use the favorable physical and biochemical properties of the bioceramic material as long as there is no satisfactory solution for a stable cementless fixation of the femoral stem in to the bone. The advantages of the Lindenhof prosthesis predominate the disadvantages: expensive instruments and a post-operative treatment of several months.

Prosthesis infections after orthopedic joint replacement

DEFF Research Database (Denmark)

Song, Zhijun; Borgwardt, Lotte; Høiby, Niels

2013-01-01

Prosthesis-related infection is a serious complication for patients after orthopedic joint replacement, which is currently difficult to treat with antibiotic therapy. Consequently, in most cases, removal of the infected prosthesis is the only solution to cure the infection. It is, therefore...

A phantom study of dose compensation behind hip prosthesis using portal dosimetry and dynamic MLC

International Nuclear Information System (INIS)

Nielsen, Martin Skovmos; Carl, Jesper; Nielsen, Jane

2008-01-01

Background and purpose: A dose compensation method is presented for patients with hip prosthesis based on Dynamic Multi Leaves Collimator (DMLC) planning. Calculations are done from an exit Portal Dose Image (PDI) from 6 MV Photon beam using an Electronic Portal Imaging Device (EPID) from Varian. Four different hip prostheses are used for this work. Methods: From an exit PDI the fluence needed to yield a uniform dose distribution behind the prosthesis is calculated. To back-project the dose distribution through the phantom, the lateral scatter is removed by deconvolution with a point spread function (PSF) determined for depths from 10 to 40 cm. The dose maximum, D max , is determined from the primary plan which delivers the PDI. A further deconvolution to remove the dose glare effect in the EPID is performed as well. Additionally, this calculated fluence distribution is imported into the Treatment Planning System (TPS) for the final calculation of a DMLC plan. The fluence file contains information such as the relative central axis (CAX) position, grid size and fluence size needed for correct delivery of the DMLC plan. GafChromic EBT films positioned at 10 cm depth are used as verification of uniform dose distributions behind the prostheses. As the prosthesis is positioned at the phantom surface the dose verifications are done 10 cm from the prosthesis. Conclusion: The film measurement with 6 MV photon beam shows uniform doses within 5% for most points, but with hot/cold spots of 10% near the femoral head prostheses

21 CFR 872.3950 - Glenoid fossa prosthesis.

Science.gov (United States)

2010-04-01

...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3950 Glenoid fossa prosthesis. (a) Identification. A glenoid fossa prosthesis is a device that is intended to be implanted in the temporomandibular...

Golf hand prosthesis performance of transradial amputees.

Science.gov (United States)

Carey, Stephanie L; Wernke, Matthew M; Lura, Derek J; Kahle, Jason T; Dubey, Rajiv V; Highsmith, M Jason

2015-06-01

Typical upper limb prostheses may limit sports participation; therefore, specialized terminal devices are often needed. The purpose of this study was to evaluate the ability of transradial amputees to play golf using a specialized terminal device. Club head speed, X-factor, and elbow motion of two individuals with transradial amputations using an Eagle Golf terminal device were compared to a non-amputee during a golf swing. Measurements were collected pre/post training with various stances and grips. Both prosthesis users preferred a right-handed stance initially; however, after training, one preferred a left-handed stance. The amputees had slower club head speeds and a lower X-factor compared to the non-amputee golfer, but increased their individual elbow motion on the prosthetic side after training. Amputees enjoyed using the device, and it may provide kinematic benefits indicated by the increase in elbow flexion on the prosthetic side. The transradial amputees were able to swing a golf club with sufficient repetition, form, and velocity to play golf recreationally. Increased elbow flexion on the prosthetic side suggests a potential benefit from using the Eagle Golf terminal device. Participating in recreational sports can increase amputees' health and quality of life. © The International Society for Prosthetics and Orthotics 2014.

[Avascular necrosis of the femoral head].

Science.gov (United States)

Porubský, Peter; Trč, Tomáš; Havlas, Vojtěch; Smetana, Pavel

Avascular necrosis of the femoral head in adults is not common, but not too rare diseases. In orthopedic practice, it is one of the diseases that are causing implantation of hip replacement at a relatively early age. In the early detection and initiation of therapy can delay the implantation of prosthesis for several years, which is certainly more convenient for the patient and beneficial. This article is intended to acquaint the reader with the basic diagnostic procedures and therapy.

Failed total carpometacarpal joint prosthesis of the thumb

DEFF Research Database (Denmark)

Hansen, Torben Bæk; Homilius, Morten

2010-01-01

Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis. T...... in eight of 10 patients, but the mean Disabilities of the arm, shoulder, and hand (DASH) scores, self-reported pinch-grip-related function, and pain were comparable with our earlier published results with the Elektra carpometacarpal total joint prosthesis.......Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis....... The male:female ratio was 1:4 and the mean duration of observation 32 months (range 6-52). In three patients the revised implant was a MOJE uncemented carpometacarpal joint prosthesis and in seven patients an Elektra uncemented one. At follow-up grip strength was reduced to less than 90% of the other hand...

Stretch due to Penile Prosthesis Reservoir Migration

Directory of Open Access Journals (Sweden)

E. Baten

2016-03-01

Full Text Available A 43-year old patient presented to the emergency department with stretch, due to impossible deflation of the penile prosthesis, 4 years after successful implant. A CT-scan showed migration of the reservoir to the left rectus abdominis muscle. Refilling of the reservoir was inhibited by muscular compression, causing stretch. Removal and replacement of the reservoir was performed, after which the prosthesis was well-functioning again. Migration of the penile prosthesis reservoir is extremely rare but can cause several complications, such as stretch.

Rehabilitation of amputed thumb with a silicone prosthesis

OpenAIRE

Asnani, Pooja; Shivalingappa, Chandu Giriyapura; Mishra, Sunil Kumar; Somkuwar, Kirti; Khan, Faisal

2015-01-01

Creating prosthesis, having realistic skin surface and seamless visual integration with the surrounding tissues, requires both artistic and technical skill. Anatomical design, thin margins, lifelike fingernails and realistic color/contours are essential for patient satisfaction. Prosthesis is especially useful in case of lost body parts, as reconstructive surgery cannot fully restore aesthetics. This case report describes a simple technique for fabricating silicon finger prosthesis for a pati...

Development and clinical application of a new testicular prosthesis.

Science.gov (United States)

Ning, Ye; Cai, Zhikang; Chen, Huixing; Ping, Ping; Li, Peng; Wang, Zhong; Li, Zheng

2011-11-01

A new type of testicular prosthesis made of silastic with an elliptical shape to mimic a normal testis was developed by our team and submitted for patenting in China. The prosthesis was produced in different sizes to imitate the normal testis of the patient. To investigate the effects and safety of the testicular prosthesis, 20 patients receiving testicular prosthesis implantation were recruited for this study. Follow-up after 6 months revealed no complications in the patients. All the patients answered that they were satisfied with their body image and the position of the implants, 19 patients were satisfied with the size and 16 patients were satisfied with the weight. These results show that the testicular prosthesis used in this study can meet patient's expectations. Patients undergoing orchiectomy should be offered the option to receive a testicular prosthesis implantation. The dimensions and weight of the available prosthetic implants should be further addressed to improve patient satisfaction.

Different techniques in fabrication of ocular prosthesis.

Science.gov (United States)

Cevik, Pinar; Dilber, Erhan; Eraslan, Oguz

2012-11-01

Loss of an eye caused by cancer, trauma, or congenital defect creates a deep psychological impact on an individual's life especially social and professional life. Custom-made prosthesis, compared to stock prosthesis, provides a better fit to the eye socket, better cosmetic results, and less discomfort to the patient in the long term. The main objective of this article was to describe 3 different alternative and practical techniques of fabricating custom-made ocular prosthesis. An impression of anophthalmic socket was made with the addition of cured silicone-based precision impression material in all techniques. A master cast was prepared and duplicated with condensation silicone. A self-cure acrylic resin was polymerized in the silicone model and was fitted into the patient's eye socket. A digital photograph of the patient's iris was made using a digital camera and printed on good-quality photo paper in various shades and sizes in the first and the second techniques. Then the photo paper was coated with PVC so as not to allow any color flowing. The proper iris was then inserted to the acrylic base. The prosthesis was final processed using orthodontic heat polymerizing clear acrylic resin.In the other technique, after the trying-in process with wax pattern, an acrylic base was fabricated using heat polymerizing scleral acrylic resin. The prosthetic iris was fabricated from a transparent contact lens by painting the lens with watercolor paints and attaching it to an acrylic resin with tissue conditioner. The final process was made with heat polymerizing transparent acrylic resin. Custom-made prosthesis allows better esthetic and functional results to the patient in comparison to stock prosthesis. Further follow-up is necessary to check the condition and fit of the ocular prosthesis in such patients.

Femoral Prosthesis Infection by Rhodotorula mucilaginosa▿

Science.gov (United States)

Savini, Vincenzo; Sozio, Federica; Catavitello, Chiara; Talia, Marzia; Manna, Assunta; Febbo, Fabio; Balbinot, Andrea; Di Bonaventura, Giovanni; Piccolomini, Raffaele; Parruti, Giustino; D'Antonio, Domenico

2008-01-01

This case report is a case history of a femoral prosthesis infection caused by Rhodotorula mucilaginosa in a human immunodeficiency virus patient. Though the pathogenicity of this organism for bone tissue has been previously reported, this is the first reported case of an orthopedic prosthesis infection by this species of the genus Rhodotorula. PMID:18753353

Kinematic analysis of a posterior-stabilized knee prosthesis.

Science.gov (United States)

Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

2015-01-20

The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0-135° flexion. Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, "rollback" compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis.

Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

Directory of Open Access Journals (Sweden)

Zhi-Xin Zhao

2015-01-01

Full Text Available Background: The goal of total knee arthroplasty (TKA is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0-135° flexion. Results: Both the output data trends and the measured values derived from the normal knee′s kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, "rollback" compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis.

Kinematic Analysis of a Posterior-stabilized Knee Prosthesis

Science.gov (United States)

Zhao, Zhi-Xin; Wen, Liang; Qu, Tie-Bing; Hou, Li-Li; Xiang, Dong; Bin, Jia

2015-01-01

Background: The goal of total knee arthroplasty (TKA) is to restore knee kinematics. Knee prosthesis design plays a very important role in successful restoration. Here, kinematics models of normal and prosthetic knees were created and validated using previously published data. Methods: Computed tomography and magnetic resonance imaging scans of a healthy, anticorrosive female cadaver were used to establish a model of the entire lower limbs, including the femur, tibia, patella, fibula, distal femur cartilage, and medial and lateral menisci, as well as the anterior cruciate, posterior cruciate, medial collateral, and lateral collateral ligaments. The data from the three-dimensional models of the normal knee joint and a posterior-stabilized (PS) knee prosthesis were imported into finite element analysis software to create the final kinematic model of the TKA prosthesis, which was then validated by comparison with a previous study. The displacement of the medial/lateral femur and the internal rotation angle of the tibia were analyzed during 0–135° flexion. Results: Both the output data trends and the measured values derived from the normal knee's kinematics model were very close to the results reported in a previous in vivo study, suggesting that this model can be used for further analyses. The PS knee prosthesis underwent an abnormal forward displacement compared with the normal knee and has insufficient, or insufficiently aggressive, “rollback” compared with the lateral femur of the normal knee. In addition, a certain degree of reverse rotation occurs during flexion of the PS knee prosthesis. Conclusions: There were still several differences between the kinematics of the PS knee prosthesis and a normal knee, suggesting room for improving the design of the PS knee prosthesis. The abnormal kinematics during early flexion shows that the design of the articular surface played a vital role in improving the kinematics of the PS knee prosthesis. PMID:25591565

Prosthetic management of mid-facial defect with magnet-retained silicone prosthesis.

Science.gov (United States)

Buzayan, Muaiyed M

2014-02-01

Mid-facial defect is one of the most disfiguring and impairing defects. A design of prosthesis that is aesthetic and stable can be precious to a patient who has lost part of his face due to surgical excision. Prosthesis can restore the patients' self-esteem and confidence, which affects the patients and their life style. The aim of this case report is to describe a technique of mid-facial silicone prosthesis fabrication. To provide an aesthetic and stable facial prosthesis, the extra-oral prosthesis was fabricated using silicone material, while the intra-oral defect was restored with obturator prosthesis, and then both prostheses were connected and attached to each other using magnets. This clinical report describes the rehabilitation of a large mid-facial defect with a two-piece prosthesis. The silicone facial prosthesis was made hollow and lighter by using an acrylic framework. Two acrylic channels were included within the facial prosthesis to provide the patient with clean and patent airways. A sectional mid-facial prosthesis was made and retained in place by using magnets, which resulted in a significant improvement in the aesthetical and functional outcome without the need for plastic surgery. Silicone prostheses are reliable alternatives to surgery and should be considered in selected cases.

Channel selection for simultaneous and proportional myoelectric prosthesis control of multiple degrees-of-freedom

Science.gov (United States)

Hwang, Han-Jeong; Hahne, Janne Mathias; Müller, Klaus-Robert

2014-10-01

Objective. Recent studies have shown the possibility of simultaneous and proportional control of electrically powered upper-limb prostheses, but there has been little investigation on optimal channel selection. The objective of this study is to find a robust channel selection method and the channel subsets most suitable for simultaneous and proportional myoelectric prosthesis control of multiple degrees-of-freedom (DoFs). Approach. Ten able-bodied subjects and one person with congenital upper-limb deficiency took part in this study, and performed wrist movements with various combinations of two DoFs (flexion/extension and radial/ulnar deviation). During the experiment, high density electromyographic (EMG) signals and the actual wrist angles were recorded with an 8 × 24 electrode array and a motion tracking system, respectively. The wrist angles were estimated from EMG features with ridge regression using the subsets of channels chosen by three different channel selection methods: (1) least absolute shrinkage and selection operator (LASSO), (2) sequential feature selection (SFS), and (3) uniform selection (UNI). Main results. SFS generally showed higher estimation accuracy than LASSO and UNI, but LASSO always outperformed SFS in terms of robustness, such as noise addition, channel shift and training data reduction. It was also confirmed that about 95% of the original performance obtained using all channels can be retained with only 12 bipolar channels individually selected by LASSO and SFS. Significance. From the analysis results, it can be concluded that LASSO is a promising channel selection method for accurate simultaneous and proportional prosthesis control. We expect that our results will provide a useful guideline to select optimal channel subsets when developing clinical myoelectric prosthesis control systems based on continuous movements with multiple DoFs.

Body image and prosthesis satisfaction in the lower limb amputee.

OpenAIRE

Murray, Craig; Fox, Jezz

2002-01-01

Purpose: This study examines the relationship between prosthesis satisfaction and body image in lower limb prosthesis users, and the gendered variations within these relationships. Method: A total of 44 valid responses were obtained to an Internet survey regarding prosthesis satisfaction, body image, and phantom pain. Spearman Rho correlations were calculated for these three domains. Results: Moderate to high negative correlations were observed between Body Image Disturbance and Prosthesis Sa...

Self-contained inflatable penile prosthesis: magnetic resonance appearance

International Nuclear Information System (INIS)

Levin, M.F.; Munk, P.L.; Vellet, A.D.; Chin, J.L.

1994-01-01

The appearance of an inflatable penile prosthesis, visualized on a short tau inversion recovery sequence, is reported, in a patient who had magnetic resonance imaging for pelvic pain subsequent to radical cystoprostatectomy for bladder carcinoma. With suppression of adjacent fat signal, the prosthesis is well delineated from adjacent structures. The fluid-containing cylinders of the prosthesis are of very bright signal intensity, with the relief valve assembly of low signal intensity. 5 refs., 2 figs

Fabrication of temporary speech bulb prosthesis: A clinical report

OpenAIRE

Kasim Mohamed, K.; Anand Kumar, V.; Devi, N.; Padmanaban, T. V.

2010-01-01

Maxillofacial prosthesis is an art and science which not only replaces the lost structure sometimes it restores the functions also. Pharyngeal obturator is a prosthesis which closes the palatal and pharyngeal defects and improving the speech and other function. The following case report discusses palatopharyngeal insufficiency, impression procedures, fabrication of prosthesis and improvements in speech.

Femoral hip prosthesis design for Thais using multi-objective shape optimization

International Nuclear Information System (INIS)

Virulsri, Chanyaphan; Tangpornprasert, Pairat; Romtrairat, Parineak

2015-01-01

Highlights: • A multi-objective shape optimization was proposed to design hip prosthesis for Thais. • The prosthesis design was optimized in terms of safety of both cement and prosthesis. • The objective functions used the Soderberg fatigue strength formulations. • Safety factors of the cement and prosthesis are 1.200 and 1.109 respectively. • The newly designed prosthesis also fits well with chosen small-sized Thai femurs. - Abstract: The long-term success of Total Hip Arthroplasty (THA) depends largely on how well the prosthetic components fit the bones. The majority of cemented femoral hip prosthesis failures are due to aseptic loosening, which is possibly caused by cracking of the cement mantle. The strength of cement components is a function of cement mantles having adequate thickness. Since the size and shape of cemented femoral hip prostheses used in Thailand are based on designs for a Caucasian population, they do not properly conform to most Thai patients’ physical requirements. For these reasons, prostheses designed specifically for Thai patients must consider the longevity and functionality of both cement and prosthesis. The objective of this study was to discover a new design for femoral hip prostheses which is not only optimal and safe in terms of both cement and prosthesis, but also fits the selected Thai femur. This study used a small-sized Thai femoral model as a reference model for a new design. Biocompatible stainless steel 316L (SS316L) and polymethylmethacrylate (PMMA) were selected as raw materials for the prosthesis and bone cement respectively. A multi-objective shape optimization program, which is an interface between optimization C program named NSGA-II and a finite element program named ANSYS, was used to optimize longevity of femoral hip prostheses by varying shape parameters at assigned cross-sections of the selected geometry. Maximum walking loads of sixty-kilograms were applied to a finite element model for stress and

Closed-eye orbital prosthesis: a clinical report.

Science.gov (United States)

Hatamleh, Muhanad M; Watson, Jason; Srinivasan, Dilip

2015-03-01

One of the most challenging prostheses to fabricate is an acceptable orbital prosthesis. Successful reconstruction of the complex missing tissues, the globe, muscle, skin, and bony elements requires time and high levels of practical skill. A good match to the contralateral nondefect side will help mask the underlying defect and give the patient confidence to return to normal, routine life. The contralateral eye opening will commonly dictate the eye opening of such a prosthesis, but because of the expressive nature of the eye and its high levels of mobility, this can be difficult to achieve. This clinical report presents a patient who had an extended orbital exenteration and right maxillectomy to remove a maxillary squamous cell carcinoma. An alternative approach to constructing an orbital prosthesis was undertaken with the eye closed. Compared to the normal method of fabrication, this process was less complex and quicker, made the prosthesis less "staring," camouflaged the defect, and reduced the detection of the prosthesis because of movements in the remaining eye. The patient engaged in his routine daily life, which reinforced his self-esteem, confidence, and reintegration into the community. Copyright © 2015 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Split-Framework in Mandibular Implant-Supported Prosthesis

Directory of Open Access Journals (Sweden)

Danny Omar Mendoza Marin

2015-01-01

Full Text Available During oral rehabilitation of an edentulous patient with an implant-supported prosthesis, mandibular flexure must be considered an important biomechanical factor when planning the metal framework design, especially if implants are installed posterior to the interforaminal region. When an edentulous mandible is restored with a fixed implant-supported prosthesis connected by a fixed full-arch framework, mandibular flexure may cause needless stress in the overall restorative system and lead to screw loosening, poor fit of prosthesis, loss of the posterior implant, and patient’s discomfort due to deformation properties of the mandible during functional movements. The use of a split-framework could decrease the stress with a precise and passive fit on the implants and restore a more natural functional condition of the mandible, helping in the longevity of the prosthesis. Therefore, the present clinical report describes the oral rehabilitation of an edentulous patient by a mandibular fixed implant-supported prosthesis with a split-framework to compensate for mandibular flexure. Clinical Significance. The present clinical report shows that the use of a split-framework reduced the risk of loss of the posterior implants or screws loosening with acceptable patient comfort over the period of a year. The split-framework might have compensated for the mandibular flexure during functional activities.

[Mid-term effectiveness of total hip arthroplasty with collum femoris preserving prosthesis].

Science.gov (United States)

Li, Mingqing; Hu, Yihe; Li, Kanghua; Liao, Qiande; Wen, Ting; Zhong, Da

2012-08-01

To discuss the clinical application of total hip arthroplasty (THA) with collum femoris preserving (CFP) prosthesis and to analyze the mid-term effectiveness. Between January 2004 and February 2007, 45 patients (48 hips) underwent THA with CFP prosthesis. There were 29 males (31 hips) and 16 females (17 hips) with an average age of 48.8 years (range, 38-60 years), including 20 left hips, 22 right hips, and 3 bilateral hips. The causes of hip replacement were osteoarthritis (20 cases), avascular necrosis of femoral head (13 cases), dysplasia (4 cases), rheumatoid arthritis (3 cases), posttraumatic osteoarthritis (2 cases), ankylosing spondylitis (2 cases), and Perths disease (1 case). The average disease duration was 6.1 years (range, 2-13 years). Harris scores, visual analogue scale (VAS) score, and the hip range of motion (ROM) were recorded at pre- and post-operation. The X-ray films were taken at pre- and post-operation to observe the position, loosening of the prosthesis, and ectopic ossification. The gait of patients were also evaluated during follow-up. Short-form 36 health survey scale (SF-36) was used to evaluate the life quality of patients. All 45 patients were followed up 5-8 years with an average of 6.4 years. All the incisions healed by first intention. No infection, hip dislocation, nerve injury, or deep vein thrombosis occurred. Six cleavage fractures (13.3%) of the lateral femoral diaphysis at the distal prosthesis occurred during operation, which healed at 8 months postoperatively without any treatment. Mild ectopic ossification occurred in 4 patients (8.9%) who had no discomfort. Five patients (11.1%) had bone mineral density loss in the region of the proximal femur. The survival rates of the cups and stems were all 100% at last follow-up. The results of Harris score, VAS score, and ROM of the hip joint at 1 year postoperatively and last follow-up were significantly better than preoperative ones (P 0.05) except the Harris score (P fair in 6 hips

Clinical Outcomes of Penile Prosthesis Implantation Surgery

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Onur Dede

2016-06-01

Full Text Available Objective: We aimed to evaluating the outcomes of in­flatable penile prosthesis implantations and partner sat­isfaction. Methods: Data of 52 patients who underwent penile prosthesis implantation in single center between May 2010 and December 2015 were retrospectively analyzed. Types of prosthesis, complication and satisfaction rates of patients were recorded by EDITS (Erectile Dysfunction Inventory of Treatment Satisfaction questionnaire was used. Results: The mean age was 49.2±14.7 years for patients. The mean follow-up durations for 34.3±12.5 months. The mean hospital stay was 3.84±1.52 days. Evaluating of the couples satisfaction revealed that 44 (84% of the patient were very satisfied. There was not any complication and no patient need to underwent revision surgery. Conclusion: Inflatable penile prosthesis implants, with high levels of treatment success, patient and partner sat­isfaction, are effective and safe options for treatment of organic erectile dysfunction with acceptable complication and revision rates.

Hearing results using the SMart piston prosthesis.

Science.gov (United States)

Fayad, Jose N; Semaan, Maroun T; Meier, Josh C; House, John W

2009-12-01

SMart, a newly introduced piston prosthesis for stapedotomy, is a nitinol-based, heat-activated, self-crimping prosthesis. We review our hearing results and postoperative complications using this self-crimped piston prosthesis and compare them with those obtained using stainless steel or platinum piston prostheses. Audiometric results using the SMart piston are identical to those obtained using a conventional piston prosthesis. Retrospective chart review. Private neurotologic tertiary referral center. The 416 ears reviewed included 306 with a SMart prosthesis and 110 conventional prostheses. 61% were women. Mean follow-up time was 5.6 (standard deviation [SD], 6.3 mo) and 6.9 months (SD, 7.0 mo) for the 2 groups, respectively. Stapedotomy using the SMart or a conventional (non-SMart) prosthesis. Audiometric hearing results, including pure-tone average (PTA) and air-bone gap (ABG), and prevalence of postoperative complications. Mean postoperative PTA was 32.6 (SD, 16.8) dB for the SMart group and 29.4 (SD, 13.5) dB for the non-SMart group, with ABGs of 7.6 (SD, 8.9) and 6.0 (SD, 5.2) dB, respectively. Mean change (decrease) in ABG was 18.7 (SD, 13.1) dB for the SMart group and 19.9 (SD, 10.3) dB for the non-SMart group. High-frequency bone PTAs showed overclosure of 2.0 (SD, 7.9) dB for the SMart group and 3.6 (SD, 8.6) dB for the non-SMart group. Postoperative vertigo and tinnitus were infrequent. No significant differences in these audiometric outcomes or complication rates were noted between groups. There was no significant difference in rate of gap closure to within 10 dB (78.3 versus 84.2%, SMart and non-SMart, respectively) or 20 dB (94.2 and 98.0%). Compared with conventional stapes prostheses, the nitinol-based SMart is a safe and reliable stapes prosthesis that eliminates manual crimping without significantly altering the audiometric outcome. Complications are rare, but longer follow-up is needed before establishing long-term stability.

Difficult factors in Management of Impacted Dental Prosthesis in Esophagus

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Efiaty A. Soepardi

2005-03-01

Full Text Available A dental prosthesis which ingested and impacted in esophagus, is an emergency case and life threatening, so require immediate esophagoscopy intervention for removing. The objective of this study is to assess some factors can caused dtfficulties in diagnosing and treating the ingested and impacted dental prosthesis in the esophagus and their complications. This retrospective study analyzed patient’s chart whose underwent esophagoscopy for removing the impacted dental prosthesis in Dr. Cipto Mangunkusumo General Hospital, Jakarta, Indonesia during a period between January 1997 and December 2003. Neck-chest X-ray and esophagoscopy were performed in all patients to identify the existence of the dental prosthesis as a diagnostic and treatment procedure. The length of time for removing the dental prosthesis was recorded and stated as a less difficult esophagoscopy when it takes time less than 60 minutes and as a difficult  esophagoscopy takes 60 minutes or longer. Some risk difficulties factors were statistically analyzed. There were 53 patients of ingested dental prosthesis in esophagus. Only 51 cases were analyzed According to the length of time for removing the dental prosthesis by esophagoscopy, 22 patients were recorded as less difficult cases and 29 patients as difficult cases. Two cases among the cases needed cervicotomy after unsuccessful esophagoscopy removal. The difficulties to diagnose an impacted dental prosthesis in the esophagus caused by unreliable clinical history, unclear signs and symptoms, unable to be detected by X-ray and was not found during esophagoscopy. The difficulties in treating due to mucosal laceration, edema, bleeding, failure of the first extraction and conformity with the size and shape, the wire outside the dental prosthesis and the length of time stayed in the esophagus. (Med J Indones 2005; 14: 33-6Keywords: ingested dental prosthesis, radioluscent foreign body, length of time of esophagoscopy

Impact of aortic prosthesis-patient mismatch on left ventricular mass regression.

Science.gov (United States)

Alassal, Mohamed A; Ibrahim, Bedir M; Elsadeck, Nabil

2014-06-01

Prostheses used for aortic valve replacement may be small in relation to body size, causing prosthesis-patient mismatch and delaying left ventricular mass regression. This study examined the effect of prosthesis-patient mismatch on regression of left ventricular mass after aortic valve replacement. We prospectively studied 96 patients undergoing aortic valve replacement between 2007 and 2012. Mean and peak gradients and indexed effective orifice area were measured by transthoracic echocardiography at 3 and 6 months postoperatively. Patient-prosthesis mismatch was defined as indexed effective orifice area ≤0.85 cm(2)·m(-2). Moderate prosthesis-patient mismatch was present in 25% of patients. There were no significant differences in demographic and operative data between patients with and without prosthesis-patient mismatch. Left ventricular dimensions, posterior wall thickness, transvalvular gradients, and left ventricular mass decreased significantly after aortic valve replacement in both groups. The interventricular septal diameter and left ventricular mass index regression, and left ventricular ejection fraction were better in patients without prosthesis-patient mismatch. There was a significant positive correlation between the postoperative indexed effective orifice area of each valve prosthesis and the rate of left ventricular mass regression. Prosthesis-patient mismatch leads to higher transprosthetic gradients and impaired left ventricular mass regression. A small-sized valve prosthesis does not necessarily result in prosthesis-patient mismatch, and may be perfectly adequate in patient with small body size. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

[The endo-exo prosthesis for patients with a problematic amputation stump].

Science.gov (United States)

Frölke, Jan Paul M; van de Meent, Henk

2010-01-01

Following lower limb amputation, quality of life is highly related to the ability to use a prosthetic limb. The conventional way to attach a prosthetic limb to the body is with a socket. Many patients experience serious discomfort wearing a conventional prosthesis because of pain, instability during walking, pressure sores, bad smell or skin irritation. In addition, sitting is uncomfortable and pelvic and lower back pain due to unstable gait is often seen in these patients. The main disadvantage of the current prosthesis is the attachment of a rigid prosthesis socket to a soft and variable body. The socket must fit tightly for stability during walking but should also be comfortable for sitting. The implantation of an osseointegrated, intramedullary, transcutaneously conducted prosthesis is a new procedure for attaching a limb prosthesis to the human body without the disadvantages of the conventional prosthesis. The intramedullary prosthesis is designed with a rough surface resembling cancellous bone to enable a secure solid integration with the long bone. We treated two patients with this new prosthesis, a 44-year-old man after a transfemoral amputation, and a 32-year-old woman after a lower leg amputation; both amputations were necessary because of trauma. Those two patients are now, more than one year after the operation, showing excellent functional results without infectious complications. We assume that endo-exo prosthesis may be a promising option for selected patients unable to use a conventional prosthesis because of a problematic amputation stump.

Clinical predictors of prosthesis-patient mismatch after aortic valve replacement for aortic stenosis

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Luis M Astudillo

2012-01-01

Full Text Available OBJECTIVE: We sought to ascertain predictors of Patient Prosthesis Mismatch, an independent predictor of mortality, in patients with aortic stenosis using bioprosthetic valves. METHOD: We analyzed 2,107 sequential surgeries. Patient Prosthesis Mismatch was calculated using the effective orifice area of the prosthesis divided by the patient's body surface area. We defined nonsignificant, moderate, and severe Patient Prosthesis Mismatch as effective orifice area indexes of .0.85 cm²/m, 0.85-0.66 cm²/m², and <0.65 cm²/m², respectively. RESULTS: A total of 311 bioprosthetic patients were identified. The incidence of nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 41%, 42, and 16%, respectively. Severe Patient Prosthesis Mismatch was significantly more prevalent in females (82%. In severe Patient Prosthesis Mismatch, the perfusion and the crossclamp times were considerably lower when compared with nonsignificant Patient Prosthesis Mismatch and moderate Patient Prosthesis Mismatch. Patients with severe Patient Prosthesis Mismatch had a significantly higher likelihood of spending time in the intensive care unit and a significantly longer length of stay in the hospital. Body surface area was not different in severe Patient Prosthesis Mismatch when compared with nonsignificant Patient Prosthesis Mismatch. In-hospital mortality in patients with nonsignificant, moderate, and severe Patient Prosthesis Mismatch was 2.3%, 6.1%, and 8%, respectively. Minimally invasive surgery was significantly associated with moderate Patient Prosthesis Mismatch in 49% of the patients, but not with severe Patient Prosthesis Mismatch. CONCLUSION: Severe Patient Prosthesis Mismatch is more common in females, but not in those with minimal available body surface area. Though operative times were shorter in these patients, intensive care unit and hospital lengths of stay were longer. Surgeons and cardiologists should be cognizant of these clinical

The unipolar ASR : Viable option in unsalvageable femoral head conditions in the young patient

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Marya SKS

2006-01-01

Full Text Available Background: The management of unsalvageable femoral head conditions in the young patient has remained an unresolved dilemma. Articular surface replacement of the hip has recently made some headway in terms of providing near-normal hip joint mechanics and function. However, this surgery has been limited to early stages of arthritis only with reasonable maintenance of head-neck congruity and morphology. Femoral neck fractures, osteonecrosis with large segment collapse, advanced arthritis with femoral incongruity, etc are traditional contraindications to the resurfacing technique. Methods: We present here a report on our series of 20 cases of unsalvageable femoral heads in young patients (age range, 27 to 52yrs, over a twelve month period (Aug 2004 to Jul 2005, treated with the unipolar ASR prosthesis. Fifteen patients (two had bilateral hip pathology had primary or secondary arthritis (degenerative, post-traumatic, ankylosing spondylitis and post-avascular necrosis while three had old operated femoral neck fractures. All patients underwent hip replacement surgery using the Unipolar ASR prosthesis. Results: Clinical and radiological results at 6-month follow up have been very encouraging and warrant further study. At an average of 4 months post-operatively, patients were able to squat, sit on the ground and perform light sporting activities. Conclusions: The Unipolar ASR prosthesis is an extension of the articular resurfacing technique employing similar principles (large size bearings, metal-on-metal interfaces, and has incorporated the advantages of the uncemented technique. We propose that this technique be more frequently used so as to brighten the prognosis of the young active patient with unsalvageable hip conditions, especially in the Asian scenario.

Modelling and analysis of radial thermal stresses and temperature ...

African Journals Online (AJOL)

user

it acts as an insulating medium and prevents the heat flow, hence the need of providing insulation coating on valves is ... geometry metal components (piston, liner and cylinder head) and found a satisfactory .... model. Step8: Find the radial thermal stress at all the nodal point with the use of temperature ..... Cast iron St. 70.

Intermittent, noncyclic dysfunction of a mechanical aortic prosthesis by pannus formation.

Science.gov (United States)

Giroux, Sylvie K; Labinaz, Marino X; Grisoli, Dominique; Klug, Andrew P; Veinot, John P; Burwash, Ian G

2010-01-01

Mechanical aortic prosthesis dysfunction can result from thrombosis or pannus formation. Pannus formation usually restricts systolic excursion of the occluding disk, resulting in progressive stenosis of the aortic prosthesis. Intermittent dysfunction of a mechanical aortic prosthesis is usually ascribed to thrombus formation. We describe an unusual case of intermittent, noncyclic dysfunction of a mechanical aortic prosthesis due to pannus formation in the absence of systolic restriction of disk excursion that presented with intermittent massive aortic regurgitation, severe ischemia, and shock. Pannus formation should be considered as a potential cause of acute intermittent severe aortic regurgitation in a patient with a mechanical aortic prosthesis.

21 CFR 888.3760 - Wrist joint carpal scaphoid polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint carpal scaphoid polymer prosthesis. 888.3760 Section 888.3760 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... scaphoid polymer prosthesis. (a) Identification. A wrist joint carpal scaphoid polymer prosthesis is a one...

21 CFR 888.3750 - Wrist joint carpal lunate polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint carpal lunate polymer prosthesis. 888.3750 Section 888.3750 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... lunate polymer prosthesis. (a) Identification. A wrist joint carpal lunate prosthesis is a one-piece...

21 CFR 888.3770 - Wrist joint carpal trapezium polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint carpal trapezium polymer prosthesis. 888.3770 Section 888.3770 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... trapezium polymer prosthesis. (a) Identification. A wrist joint carpal trapezium polymer prosthesis is a one...

A modified technique for retention of orbital prosthesis

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Sameera R Shaikh

2011-01-01

Full Text Available An orbital defect (congenital or acquired causes severe facial asymmetry and disfigurement, which results in psychological and social disturbances to the patient. It becomes a challenging task for a maxillofacial prosthodontist to fabricate a prosthesis that replicates the healthy side of the face. Success of the prosthesis depends primarily on satisfactory retention of the same. This clinical report illustrates rehabilitation of a patient with an orbital defect by fabricating a hollow orbital prosthesis, utilizing anatomical undercuts for retention using an acrylic resin template relined by a resilient denture liner.

Selection of contact bearing couple materials for hip prosthesis using finite element analysis under static conditions

Science.gov (United States)

Arirajan, K. A.; Chockalingam, K.; Vignesh, C.

2018-04-01

Implants are the artificial parts to replace the missing bones or joints in human anatomy to give mechanical support. Hip joint replacement is an important issue in orthopaedic surgery. The main concern limiting the long-run success of the total hip replacement is the limited service life. Hip replacement technique is widely used in replacing the femur head and acetabular cup by materials that are highly biocompatible. The success of the artificial hip replacement depends upon proper material selection, structure, and shape of the hip prosthesis. Many orthopaedic analyses have been tried with different materials, but ended with partial success on the application side. It is a critical task for selecting the best material pair in the hip prosthesis design. This work develops the finite element analysis of an artificial hip implant to study highest von Mises stress, contact pressure and elastic strain occurs for the dissimilar material combination. The different bearing couple considered for the analysis are Metal on Metal, Metal on Plastic, Metal on Ceramic, Ceramic on Plastic, Ceramic on Ceramic combinations. The analysis is carried out at different static positions of a human (i.e) standing, sitting. The results reveals that the combination with metal in contact with plastic (i.e) Titanium femoral head paired with Ultra High Molecular Weight Poly Ethylene acetabular cup reduces maximum von Mises stress and also it gives lowest contact pressure than other combination of bearing couples.

Communication Protocol for Advanced Prosthesis Components

OpenAIRE

Karnå, David

2007-01-01

It would be of great value for the prosthesis industry to achieve an open standard for communication in upper limb prostheses. Cooperation between NTNU and the University of New Brunswick has resulted in a functional requirements specification for such a standard, SCIP(Standardised Communication Interface in Prostheses). The special challenges for communication in a prosthesis system are possible noisy environments, high demands for light weight, safety for the user and the fact that devices ...

Posttraumatic Proximal Radioulnar Synostosis after Closed Reduction for a Radial Neck and Olecranon Fracture

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Patrick R. Keller

2018-01-01

Full Text Available Posttraumatic proximal radioulnar synostosis (PPRUS is a severe complication of radial head and neck fractures known to occur after severe injury or operative fixation. Cases of PPRUS occurring after minimally displaced, nonoperatively treated radial neck injuries are, by contrast, extremely rare. Here, we present a pediatric case of PPRUS that developed after a nonoperatively treated minimally displaced radial neck fracture with concomitant olecranon fracture. While more cases are needed to establish the association between this pattern of injury and PPRUS, we recommend that when encountering patients with a minimally displaced radial neck fracture and a concomitant elbow injury, the rare possibility of developing proximal radioulnar synostosis should be considered.

SU-G-IeP2-03: Comparison of Dose Calculation On MAR (metal Artifact Reduction) and Non-MAR Datasets for Pelvic Patients with Hip Prosthesis and Head and Neck Patients with Dental Filling

International Nuclear Information System (INIS)

Huang, V; Kohli, K

2016-01-01

Purpose: Metal artifact reduction (MAR) software in computed tomography (CT) was previously evaluated with phantoms demonstrating the algorithm is capable of reducing metal artifacts without affecting the overall image quality. The goal of this study is to determine the dosimetric impact when calculating with CT datasets reconstructed with and without MAR software. Methods: Twelve head and neck cancer patients with dental fillings and four pelvic cancer patients with hip prosthesis were scanned with a GE Optima RT 580 CT scanner. Images were reconstructed with and without the MAR software. 6MV IMRT and VMAT plans were calculated with AAA on the MAR dataset until all constraints met our clinic’s guidelines. Contours from the MAR dataset were copied to the non-MAR dataset. Next, dose calculation on the non-MAR dataset was performed using the same field arrangements and fluence as the MAR plan. Conformality index, D99% and V100% to PTV were compared between MAR and non-MAR plans. Results: Differences between MAR and non-MAR plans were evaluated. For head and neck plans, the largest variations in conformality index, D99% and V100% were −3.8%, −0.9% and −2.1% respectively whereas for pelvic plans, the biggest discrepancies were −32.7%, −0.4% and -33.5% respectively. The dosimetric impact from hip prosthesis is greater because it produces more artifacts compared to dental fillings. Coverage to PTV can increase or decrease depending on the artifacts since dark streaks reduce the HU whereas bright streaks increase the HU. In the majority of the cases, PTV dose in the non-MAR plans is higher than MAR plans. Conclusion: With the presence of metals, MAR algorithm can allow more accurate delineation of targets and OARs. Dose difference between MAR and non-MAR plans depends on the proximity of the organ to the high density material, the streaking artifacts and the beam arrangements of the plan.

SU-G-IeP2-03: Comparison of Dose Calculation On MAR (metal Artifact Reduction) and Non-MAR Datasets for Pelvic Patients with Hip Prosthesis and Head and Neck Patients with Dental Filling

Energy Technology Data Exchange (ETDEWEB)

Huang, V; Kohli, K [BC Cancer Agency, Surrey, BC (United Kingdom)

2016-06-15

Purpose: Metal artifact reduction (MAR) software in computed tomography (CT) was previously evaluated with phantoms demonstrating the algorithm is capable of reducing metal artifacts without affecting the overall image quality. The goal of this study is to determine the dosimetric impact when calculating with CT datasets reconstructed with and without MAR software. Methods: Twelve head and neck cancer patients with dental fillings and four pelvic cancer patients with hip prosthesis were scanned with a GE Optima RT 580 CT scanner. Images were reconstructed with and without the MAR software. 6MV IMRT and VMAT plans were calculated with AAA on the MAR dataset until all constraints met our clinic’s guidelines. Contours from the MAR dataset were copied to the non-MAR dataset. Next, dose calculation on the non-MAR dataset was performed using the same field arrangements and fluence as the MAR plan. Conformality index, D99% and V100% to PTV were compared between MAR and non-MAR plans. Results: Differences between MAR and non-MAR plans were evaluated. For head and neck plans, the largest variations in conformality index, D99% and V100% were −3.8%, −0.9% and −2.1% respectively whereas for pelvic plans, the biggest discrepancies were −32.7%, −0.4% and -33.5% respectively. The dosimetric impact from hip prosthesis is greater because it produces more artifacts compared to dental fillings. Coverage to PTV can increase or decrease depending on the artifacts since dark streaks reduce the HU whereas bright streaks increase the HU. In the majority of the cases, PTV dose in the non-MAR plans is higher than MAR plans. Conclusion: With the presence of metals, MAR algorithm can allow more accurate delineation of targets and OARs. Dose difference between MAR and non-MAR plans depends on the proximity of the organ to the high density material, the streaking artifacts and the beam arrangements of the plan.

Fabrication of a Cranial Prosthesis Combined with an Ocular Prosthesis Using Rapid Prototyping: A Case Report

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Gayatri Shankaran

2016-08-01

Full Text Available Rapid prototyping (RP is a technique of manufacturing parts by the additive layer manufacturing technology; where, a three-dimensional (3D model created in a computer aided design (CAD system is sectioned into 2D profiles, which are further constructed by RP layer by layer. Its use is not limited to industrial or engineering fields and has extended to the medical field for the manufacturing of custom implants and prostheses, the study of anatomy and surgical planning. Nowadays, dentists are more frequently encountered with the individuals affected with craniofacial defects due to trauma. In such cases, the cranio-maxillofacial rehabilitation is a real challenge to bring the patients back to society and promote their well-being. The conventional impression technique for facial prosthesis fabrication has the disadvantage of deforming the soft tissue and causing discomfort for the patient. Herein, we describe the fabrication of a cranial prosthesis combined with an ocular prosthesis with RP and stereolithography.

Fabrication of a Cranial Prosthesis Combined with an Ocular Prosthesis Using Rapid Prototyping: A Case Report.

Science.gov (United States)

Shankaran, Gayatri; Deogade, Suryakant Chhagan; Dhirawani, Rajesh

2016-01-01

Rapid prototyping (RP) is a technique of manufacturing parts by the additive layer manufacturing technology; where, a three-dimensional (3D) model created in a computer aided design (CAD) system is sectioned into 2D profiles, which are further constructed by RP layer by layer. Its use is not limited to industrial or engineering fields and has extended to the medical field for the manufacturing of custom implants and prostheses, the study of anatomy and surgical planning. Nowadays, dentists are more frequently encountered with the individuals affected with craniofacial defects due to trauma. In such cases, the craniomaxillofacial rehabilitation is a real challenge to bring the patients back to society and promote their well-being. The conventional impression technique for facial prosthesis fabrication has the disadvantage of deforming the soft tissue and causing discomfort for the patient. Herein, we describe the fabrication of a cranial prosthesis combined with an ocular prosthesis with RP and stereolithography.

Relationship between the Ulnar Nerve and the Branches of the Radial Nerve to the Medial Head of the Triceps Brachii Muscle.

Science.gov (United States)

Sh, Cho; Ih, Chung; Uy, Lee

2018-05-17

One branch of the radial nerve to the medial head of the triceps brachii muscle (MHN) has been described as accompanying or joining the ulnar nerve. Mostly two MHN branches have been reported, with some reports of one; however, the topographical anatomy is not well documented. We dissected 52 upper limbs from adult cadavers and found one, two, and three MHN branches in 9.6%, 80.8%, and 9.6% of cases, respectively. The MHN accompanying the ulnar nerve was always the superior MHN. The relationship between the ulnar nerve and the MHN was classified into four types according to whether the MHN was enveloped along with the ulnar nerve in the connective tissue sheath and whether it was in contact with the ulnar nerve. It contacted the ulnar nerve in 75.0% of cases and accompanied it over a mean distance of 73.6 mm (range 36-116 mm). In all cases in which the connective tissue sheath enveloped the branch of the MHN and the ulnar nerve, removing the sheath confirmed that the MHN branch originated from the radial nerve. The detailed findings and anatomical measurements of the MHN in this study will help in identifying its branches during surgical procedures. This article is protected by copyright. All rights reserved. © 2018 Wiley Periodicals, Inc.

Metabolics of stair ascent with a powered transfemoral prosthesis.

Science.gov (United States)

Ledoux, E D; Lawson, B E; Shultz, A H; Bartlett, H L; Goldfarb, M

2015-01-01

This paper evaluates the effectiveness of a powered knee and ankle prosthesis for stair ascent through a metabolic assessment comparing energy expenditure of a single transfemoral amputee subject while ascending stairs with the powered prosthesis relative to his passive daily use device, as well as comparing the kinematics and kinetics obtained with the passive prosthesis to healthy biomechanics. The subject wore a portable system that measured pulmonary gaseous exchange rates of oxygen and carbon dioxide while he ascended stairs with each of the prostheses in alternating tests. The results indicated that the amputee's energy expenditure decreased by 32 percent while climbing with the powered prosthesis as compared to his passive one, and the kinematics and kinetics achieved were representative of healthy biomechanics.

Morphological experimental study of bone stress at the interface acetabular bone/prosthetic cup in the bipolar hip prosthesis.

Science.gov (United States)

Anuşca, D; Pleşea, I E; Iliescu, N; Tomescu, P; Poenaru, F; Dascălu, V; Pop, O T

2006-01-01

By calculating the tension and distortion of the elements composing the bipolar prosthesis under extreme conditions encountered in real life using a special post-processing program, we established the variation curves of the contact pressure at the hip bone-cup, armor-cup and cup-femoral head interface. By comparing the data obtained from all the examined cases, important conclusions were drawn regarding the influence of tension and pressure distribution on the structural integrity and biomechanics of the prosthesis, as well as the acetabular wear and tear, in order to assess its reliability. The experimentally determined tension and distortion status at the acetabular bone-metal armour interface, lead to the wear and tear phenomenon, which can be explained by three mechanisms and theories incompletely reflecting the overall process. The histopathologic study of the acetabular bone tissue using FEM (finite elements method) on surgically removed specimens will probably lead to the identification of a series of factors that could reduce the rate of the wear and tear process.

Penile prosthesis implant: scientific advances and technological innovations over the last four decades.

Science.gov (United States)

Chung, Eric

2017-02-01

Despite introduction of oral phosphodiesterase type 5 inhibitors and intracavernosal vasoactive agents, penile prosthesis implant remains a relevant and desired option with sales of penile prostheses continue to stay high, as many men became refractory to medical therapy and/or seeking a more effective and permanent therapy. There are two types of penile prosthesis implants: inflatable and non-inflatable types, and the inflatable penile implants can be subdivided into single-, two- and three-piece devices. Non-inflatable penile prosthesis (non-IPP) may be referred to as semi-rigid rod or malleable prosthesis. IPP is considered a superior option to malleable prosthesis as it produces penile rigidity and flaccidity that closely replicates a normal penile erectile function. Since the introduction of IPP by Scott in 1973, surgical landscape for penile prosthesis implantation has changed dramatically. Advances in prosthesis design, device technologies and surgical techniques have made penile prosthesis implant a more natural, durable and reliable device. The following article reviews the scientific advances and technological innovation in modern penile prosthesis implants over the last four decades.

Surgical anatomy of the radial nerve at the elbow.

Science.gov (United States)

Artico, M; Telera, S; Tiengo, C; Stecco, C; Macchi, V; Porzionato, A; Vigato, E; Parenti, A; De Caro, R

2009-02-01

An anatomical study of the brachial portion of the radial nerve with surgical implications is proposed. Thirty specimens of arm from 20 fresh cadavers (11 male, 9 female) were used to examine the topographical relations of the radial nerve with reference to the following anatomical landmarks: acromion angle, medial and lateral epicondyles, point of division between the lateral and long heads of the triceps brachii, lateral intermuscular septum, site of division of the radial nerve into its superficial and posterior interosseous branches and entry and exit point of the posterior interosseous branch into the supinator muscle. The mean distances between the acromion angle and the medial and lateral levels of crossing the posterior aspect of the humerus were 109 (+/-11) and 157 (+/-11) mm, respectively. The mean length and calibre of the nerve in the groove were 59 (+/-4) and 6 (+/-1) mm, respectively. The division of the lateral and long heads of the triceps was found at a mean distance of 126 (+/-13) mm from the acromion angle. The mean distances between the lateral point of crossing the posterior aspect of the humerus and the medial and lateral epicondyles were 125 (+/-13) and 121 (+/-13) mm, respectively. The mean distance between the lateral point of crossing the posterior aspect of the humerus and the entry point in the lateral intermuscular septum (LIS) was 29 (+/-6) mm. The mean distances between the entry point of the nerve in the LIS and the medial and lateral epicondyles were 133 (+/-14) and 110 (+/-23) mm, respectively. Our study provides reliable and objective data of surgical anatomy of the radial nerve which should be always kept in mind by surgeons approaching to the surgery of the arm, in order to avoid iatrogenic injuries.

Automated estimation of hip prosthesis migration: a feasibility study

Science.gov (United States)

Vandemeulebroucke, Jef; Deklerck, Rudi; Temmermans, Frederik; Van Gompel, Gert; Buls, Nico; Scheerlinck, Thierry; de Mey, Johan

2013-09-01

A common complication associated with hip arthoplasty is prosthesis migration, and for most cemented components a migration greater than 0.85 mm within the first six months after surgery, are an indicator for prosthesis failure. Currently, prosthesis migration is evaluated using X-ray images, which can only reliably estimate migrations larger than 5 mm. We propose an automated method for estimating prosthesis migration more accurately, using CT images and image registration techniques. We report on the results obtained using an experimental set-up, in which a metal prosthesis can be translated and rotated with respect to a cadaver femur, over distances and angles applied using a combination of positioning stages. Images are first preprocessed to reduce artefacts. Bone and prosthesis are extracted using consecutive thresholding and morphological operations. Two registrations are performed, one aligning the bones and the other aligning the prostheses. The migration is estimated as the difference between the found transformations. We use a robust, multi-resolution, stochastic optimization approach, and compare the mean squared intensity differences (MS) to mutual information (MI). 30 high-resolution helical CT scans were acquired for prosthesis translations ranging from 0.05 mm to 4 mm, and rotations ranging from 0.3° to 3° . For the translations, the mean 3D registration error was found to be 0.22 mm for MS, and 0.15 mm for MI. For the rotations, the standard deviation of the estimation error was 0.18° for MS, and 0.08° for MI. The results show that the proposed approach is feasible and that clinically acceptable accuracies can be obtained. Clinical validation studies on patient images will now be undertaken.

Bending patterns of chlamydomonas flagella: III. A radial spoke head deficient mutant and a central pair deficient mutant.

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Brokaw, C J; Luck, D J

1985-01-01

Flash photomicrography at frequencies up to 300 Hz and computer-assisted image analysis have been used to obtain parameters describing the flagellar bending patterns of mutants of Chlamydomonas reinhardtii. All strains contained the uni1 mutation, to facilitate photography. The radial spoke head deficient mutant pf17, and the central pair deficient mutant, pf15, in combination with suppressor mutations that restore motility without restoring the ultrastructural or biochemical deficiencies, both generate forward mode bending patterns with increased shear amplitude and decreased asymmetry relative to the "wild-type" uni1 flagella described previously. In the reverse beating mode, the suppressed pf17 mutants generate reverse bending patterns with large shear amplitudes. Reverse beating of the suppressed pf15 mutants is rare. There is a reciprocal relationship between increased shear amplitude and decreased beat frequency, so that the velocity of sliding between flagellar microtubules is not increased by an increase in shear amplitude. The suppressor mutations alone cause decreased frequency and sliding velocity in both forward and reverse mode beating, with little change in shear amplitude or symmetry.

Availability of Dental Prosthesis Procedures in Brazilian Primary Health Care

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Maria Aparecida Gonçalves Melo Cunha

2018-01-01

Full Text Available Objectives. To describe dental prosthesis provision in the Brazilian public health service and report the performance of dental prosthesis procedures according to the Brazilian macroregions. Methods. A structured interview was conducted with senior-level health professionals from each of the 18,114 oral health teams (OHT. The dependent variables were performance of removable prostheses and prosthesis procedures, including provision of fixed prostheses by OHT. Descriptive statistics were produced together with performing a cluster analysis using SPSS version 19.0. Results. The manufacture of any type of prosthesis was done by a minority of OHT (43%. The most commonly provided types of dental prosthesis were removable full and partial dentures. Cluster 1 (teams that performed prosthesis procedures the most was composed of a smaller number of teams (n = 5,531, and Cluster 2 (composed of teams that do not perform prosthetics or that perform them in small amounts consisted of 12,583 teams. The geographic distribution of clusters reveals that the largest proportion of Cluster 1 teams is located in the Northeast (33.9% and Southeast (33.6%. Conclusions. A minority of OHT produce dental prostheses. There is an unequal geographical distribution of clusters.

Amputation and prosthesis implantation shape body and peripersonal space representations.

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Canzoneri, Elisa; Marzolla, Marilena; Amoresano, Amedeo; Verni, Gennaro; Serino, Andrea

2013-10-03

Little is known about whether and how multimodal representations of the body (BRs) and of the space around the body (Peripersonal Space, PPS) adapt to amputation and prosthesis implantation. In order to investigate this issue, we tested BR in a group of upper limb amputees by means of a tactile distance perception task and PPS by means of an audio-tactile interaction task. Subjects performed the tasks with stimulation either on the healthy limb or the stump of the amputated limb, while wearing or not wearing their prosthesis. When patients performed the tasks on the amputated limb, without the prosthesis, the perception of arm length shrank, with a concurrent shift of PPS boundaries towards the stump. Conversely, wearing the prosthesis increased the perceived length of the stump and extended the PPS boundaries so as to include the prosthetic hand, such that the prosthesis partially replaced the missing limb.

Management of long span partially edentulous maxilla with fixed removable denture prosthesis.

Science.gov (United States)

Jeyavalan, Mahilan I; Narasimman, M; Venkatakrishnan, C J; Philip, Jacob M

2012-07-01

Restoration of a long span partially edentulous maxilla with tooth supported prosthesis is challenging because of inherent anatomic limitations and unfavourable biomechanics present after the loss of teeth. A tooth supported fixed-removable prosthesis is a treatment option for restoration of such long span partially edentulous maxillary arches. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favourable biomechanical stress distribution to the remaining natural tooth abutments. This article presents a procedure for fabrication of a fixed-removable prosthesis that has cement-retained custom cast bar metal substructure and a ball attachment retained removable superstructure prosthesis.

Dosimetric influence of hip prosthesis during radiotherapeutic treatment

International Nuclear Information System (INIS)

Gschwind, R.; Buffard, E.; Masset, H.; Makovicka, L.; David, C.; David, C.; Buffard, E.

2008-01-01

As the population become aged, many patients with hip prosthesis are treated for a pelvic cancer. The recommended ballistic must avoid to pass in the prosthesis, but sometimes it is inevitable. So it is essential to quantify with accuracy the dose modifications linked to the presence of metallic implant. The aim of this study is to analyze by Monte Carlo method these modifications in simple and complex models (anthropomorphic phantom) which take into account the geometry and the composition of the prosthesis and its coatings. Then, this methodology was used to study the behaviour of a treatment planning system in theses extreme conditions. (authors)

21 CFR 888.3810 - Wrist joint ulnar (hemi-wrist) polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Wrist joint ulnar (hemi-wrist) polymer prosthesis. 888.3810 Section 888.3810 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-wrist) polymer prosthesis. (a) Identification. A wrist joint ulnar (hemi-wrist) polymer prosthesis...

21 CFR 888.3730 - Toe joint phalangeal (hemi-toe) polymer prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Toe joint phalangeal (hemi-toe) polymer prosthesis. 888.3730 Section 888.3730 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... (hemi-toe) polymer prosthesis. (a) Identification. A toe joint phalangeal (hemi-toe) polymer prosthesis...

Penile Corporeal Reconstruction during Difficult Placement of a Penile Prosthesis

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Viet Q. Tran

2008-01-01

Full Text Available For some patients with impotence and concomitant severe tunical/corporeal tissue fibrosis, insertion of a penile prosthesis is the only option to restore erectile function. Closing the tunica over an inflatable penile prosthesis in these patients can be challenging. We review our previous study which included 15 patients with severe corporeal or tunical fibrosis who underwent corporeal reconstruction with autologous rectus fascia to allow placement of an inflatable penile prosthesis. At a mean follow-up of 18 months (range 12 to 64, all patients had a prosthesis that was functioning properly without evidence of separation, herniation, or erosion of the graft. Sexual activity resumed at a mean time of 9 weeks (range 8 to 10. There were no adverse events related to the graft or its harvest. Use of rectus fascia graft for coverage of a tunical defect during a difficult penile prosthesis placement is surgically feasible, safe, and efficacious.

Design and Control of a Pneumatically Actuated Transtibial Prosthesis.

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Zheng, Hao; Shen, Xiangrong

2015-04-01

This paper presents the design and control of a pneumatically actuated transtibial prosthesis, which utilizes a pneumatic cylinder-type actuator to power the prosthetic ankle joint to support the user's locomotion. The pneumatic actuator has multiple advantages over the traditional electric motor, such as light weight, low cost, and high power-to-weight ratio. The objective of this work is to develop a compact and lightweight transtibial prosthesis, leveraging the multiple advantages provided by this highly competitive actuator. In this paper, the design details of the prosthesis are described, including the determination of performance specifications, the layout of the actuation mechanism, and the calculation of the torque capacity. Through the authors' design calculation, the prosthesis is able to provide sufficient range of motion and torque capacity to support the locomotion of a 75 kg individual. The controller design is also described, including the underlying biomechanical analysis and the formulation of the finite-state impedance controller. Finally, the human subject testing results are presented, with the data indicating that the prosthesis is able to generate a natural walking gait and sufficient power output for its amputee user.

Prosthesis rejection in acquired major upper-limb amputees: a population-based survey.

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Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-07-01

To estimate the rates of primary and secondary prosthesis rejection in acquired major upper-limb amputees (ULAs), to describe the most frequently reported reasons for rejection and to estimate the influence of background factors on the risk of rejection. Cross-sectional study analysing population-based questionnaire data (n = 224). Effects were analysed by logistic regression analyses and Cox regression analyses. Primary prosthesis rejection was found in 4.5% whereas 13.4% had discontinued prosthesis use. The main reasons reported for primary non-wear were a perceived lack of need and discrepancies between perceived need and the prostheses available. The main reasons reported for secondary prosthesis rejection were dissatisfaction with prosthetic comfort, function and control. Primary prosthesis rejection was more likely in ULAs amputated at high age and in ULAs with proximal amputations. Secondary prosthesis rejection was more likely in proximal ULAs and in women. Clinicians should be aware of the increased risk of rejection in proximal ULAs, elderly ULAs and in women. Emphasising individual needs will probably facilitate successful prosthetic fitting. Improved prosthesis quality and individualised prosthetic training may increase long-term prosthesis use. Further studies of the effect of prosthetic training and of the reasons for rejection of different prosthetic types are suggested.

Right radial nerve dysfunction following laparoscopic sigmoid colectomy

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Yoshikazu Takinami

2014-10-01

Full Text Available Here, we report a case of right radial nerve dysfunction following laparoscopic sigmoid colectomy under general anesthesia. A 75-year-old man was intubated without excessive retroflexion, and his upper body was held in place by lateral body positioners with protective cushions over the chest and acromioclavicular joints. The patient’s head was maintained at the center and held on the operation table with a memory-foam pillow to prevent hyperextension of the neck. The arms, abducted 80° with the forearms supinated, were held in place on the armrests with protective cushions. The surgical position was a 20° head-down lithotomy position with the right side of the body lowered by 15°. Surgery was completed successfully with no complications, and anesthesia time was 7 h and 37 min. After surgery, however, the patient complained of numbness and hypoesthesia on the radial and ulnar side, respectively, of the right arm from the elbow to the fingertips, with the boundary running between fingers 3 and 4. Dysesthesia was observed in the right fingertips of fingers 1–3. After 3 months of silver spike point low-frequency electrotherapy, hypoesthesia improved, while dysesthesia partially improved, in the dorsal area between right fingers 1 and 2.

Controlling a virtual forehand prosthesis using an adaptive and affective Human-Machine Interface.

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Rezazadeh, I Mohammad; Firoozabadi, S M P; Golpayegani, S M R Hashemi; Hu, H

2011-01-01

This paper presents the design of an adaptable Human-Machine Interface (HMI) for controlling virtual forearm prosthesis. Direct physical performance measures (obtained score and completion time) for the requested tasks were calculated. Furthermore, bioelectric signals from the forehead were recorded using one pair of electrodes placed on the frontal region of the subject head to extract the mental (affective) measures while performing the tasks. By employing the proposed algorithm and above measures, the proposed HMI can adapt itself to the subject's mental states, thus improving the usability of the interface. The quantitative results from 15 subjects show that the proposed HMI achieved better physical performance measures in comparison to a conventional non-adaptive myoelectric controller (p < 0.001).

Complicações decorrentes do uso de prótese vocal Complications in consequence of the vocal prosthesis use

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Leonardo de Souza Kruschewsky

2002-01-01

Full Text Available INTRODUÇÃO: Desde a primeira laringectomia total, realizada em 1873, já se tem registro do interesse em se desenvolver e recuperar a comunicabilidade verbal desses pacientes. Porém grandes progressos foram observados depois de 1979, quando se pode contar com próteses traqueoesofágicas. Mesmo sendo um enorme progresso, as próteses vocais geram complicações. OBJETIVO: Avaliar as complicações com o emprego de próteses vocais e relaciona-las com fatores clínicos e tipo de prótese. MÉTODOS: Dez pacientes submetidos a laringectomia total portando prótese fonatória foram acompanhados no serviço de Cirurgia de Cabeça e Pescoço do HCRP-FMRP-USP buscando-se registrar as complicações e relaciona-las com fatores clínicos e tipo de prótese. RESULTADOS: Foram registrados: vazamento de saliva e/ou dieta da faringe para a traquéia, infecção fungica, ausência de função da prótese e esses achados foram quantificados avaliando-se os efeitos da radioterapia e do tipo de prótese usada. CONCLUSÃO: A prótese vocal apresenta dificuldades e complicações operacionais que merecem atenção e mais estudos são necessários para se ter o perfil mais completo destes aspectos.INTRODUCTION: Since 1873 when the first total laryngectomy was performed there is a scientific interest in develop and recover patients' verbal comunication. Great successes were done after 1979, that permitted the tracheoesophagical prosthesis be a reality. Even being a special conquest the vocal prosthesis has its complications. AIM: To evaluate its complications registered with the vocal prosthesis use and its relation with patients' clinical aspects and the prosthesis kind. METHODS: Ten total laryngectomised patients from the HCRP-FMRP-USP, Head and Neck ambulatory, were followed to complications manifestations with the prosthesis use. RESULTS: Complications as saliva and/or diet passage from the pharynx to the trachea, fungal infection, prosthesis dysfunction were

Management of long span partially edentulous maxilla with fixed removable denture prosthesis

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Mahilan I Jeyavalan

2012-01-01

Full Text Available Restoration of a long span partially edentulous maxilla with tooth supported prosthesis is challenging because of inherent anatomic limitations and unfavourable biomechanics present after the loss of teeth. A tooth supported fixed-removable prosthesis is a treatment option for restoration of such long span partially edentulous maxillary arches. This prosthesis meets the requirements for esthetics, phonetics, comfort, and hygiene, as well as favourable biomechanical stress distribution to the remaining natural tooth abutments. This article presents a procedure for fabrication of a fixed-removable prosthesis that has cement-retained custom cast bar metal substructure and a ball attachment retained removable superstructure prosthesis.

21 CFR 872.3970 - Interarticular disc prosthesis (interpositional implant).

Science.gov (United States)

2010-04-01

... implant). 872.3970 Section 872.3970 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3970 Interarticular disc prosthesis (interpositional implant). (a) Identification. An interarticular disc prosthesis...

Reading visual braille with a retinal prosthesis.

Science.gov (United States)

Lauritzen, Thomas Z; Harris, Jordan; Mohand-Said, Saddek; Sahel, Jose A; Dorn, Jessy D; McClure, Kelly; Greenberg, Robert J

2012-01-01

Retinal prostheses, which restore partial vision to patients blinded by outer retinal degeneration, are currently in clinical trial. The Argus II retinal prosthesis system was recently awarded CE approval for commercial use in Europe. While retinal prosthesis users have achieved remarkable visual improvement to the point of reading letters and short sentences, the reading process is still fairly cumbersome. This study investigates the possibility of using an epiretinal prosthesis to stimulate visual braille as a sensory substitution for reading written letters and words. The Argus II retinal prosthesis system, used in this study, includes a 10 × 6 electrode array implanted epiretinally, a tiny video camera mounted on a pair of glasses, and a wearable computer that processes the video and determines the stimulation current of each electrode in real time. In the braille reading system, individual letters are created by a subset of dots from a 3 by 2 array of six dots. For the visual braille experiment, a grid of six electrodes was chosen out of the 10 × 6 Argus II array. Groups of these electrodes were then directly stimulated (bypassing the camera) to create visual percepts of individual braille letters. Experiments were performed in a single subject. Single letters were stimulated in an alternative forced choice (AFC) paradigm, and short 2-4-letter words were stimulated (one letter at a time) in an open-choice reading paradigm. The subject correctly identified 89% of single letters, 80% of 2-letter, 60% of 3-letter, and 70% of 4-letter words. This work suggests that text can successfully be stimulated and read as visual braille in retinal prosthesis patients.

Testicular prosthesis: Patient satisfaction and sexual dysfunctions in testis cancer survivors.

Science.gov (United States)

Catanzariti, Francesco; Polito, Benedetta; Polito, Massimo

2016-10-05

We studied patient satisfaction about sexual activity after prosthesis implantation using validated questionnaires with the aim to discover if testicular prosthesis could be responsible of sexual dysfunctions (erectile dysfunction or premature ejaculation). We evaluated a total of 67 men who underwent radical orchiectomy for testicular cancer and a silicon testicular prosthesis implantation from January 2008 to June 2014 at our Hospital. These patients completed 5 validated questionnaires the day before orchiectomy and 6 months after surgery: the International Index of Erectile Function 5 (IIEF5), the Premature Ejaculation Diagnostic Tool (PEDT), the Body Exposure during Sexual Activities Questionnaire (BESAQ), the Body-Esteem Scale and the Rosenberg Self- Esteem Scale. We also evaluated 6 months after surgery any defects of the prosthesis complained by the patients. The questionnaires completed by patients didn't show statistically significant changes for erectile dysfunction (p > 0.05) and premature ejaculation (p > 0.05). On the contrary the psychological questionnaires showed statistically significant change for the BESAQ (p < 0.001) and the Body Esteem Scale (p < 0.001), but not for the Rosenberg Self-Esteem Scale (p > 0,05). A total of 15 patients (22.37%) were dissatisfied about the prosthesis: the most frequent complaint (8 patients; 11.94%) was that the prosthesis was firmer than the normal testis. Testicular prosthesis implantation is a safe surgical procedure that should be always proposed before orchiectomy for cancer of the testis. The defects complained by patients with testicular prosthesis are few, they don't influence sexual activity and they aren't able to cause erectile dysfunction or premature ejaculation.

Nasal prosthesis for a patient with xeroderma pigmentosum

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Suresh Kumar

2013-01-01

Full Text Available Acquired facial defects caused by extirpation of neoplasms, congenital malformations or traumatic injury results in a huge functional, cosmetic and psychological handicap in those patients. These defects can be restored by facial prosthesis using different materials and retention methods to achieve a lifelike appearance and function. This clinical report describes a treatment schedule using silicone nasal prosthesis, which is mechanically retained for a patient who has undergone a partial rhinectomy due to basal cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of patient with a mechanically retained design using a spectacle glass frame without any prosthetic adhesives so that the patient is more comfortable and confident to resume daily activities.

The First Experience of Triple Nerve Transfer in Proximal Radial Nerve Palsy.

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Emamhadi, Mohammadreza; Andalib, Sasan

2018-01-01

Injury to distal portion of posterior cord of brachial plexus leads to palsy of radial and axillary nerves. Symptoms are usually motor deficits of the deltoid muscle; triceps brachii muscle; and extensor muscles of the wrist, thumb, and fingers. Tendon transfers, nerve grafts, and nerve transfers are options for surgical treatment of proximal radial nerve palsy to restore some motor functions. Tendon transfer is painful, requires a long immobilization, and decreases donor muscle strength; nevertheless, nerve transfer produces promising outcomes. We present a patient with proximal radial nerve palsy following a blunt injury undergoing triple nerve transfer. The patient was involved in a motorcycle accident with complete palsy of the radial and axillary nerves. After 6 months, on admission, he showed spontaneous recovery of axillary nerve palsy, but radial nerve palsy remained. We performed triple nerve transfer, fascicle of ulnar nerve to long head of the triceps branch of radial nerve, flexor digitorum superficialis branch of median nerve to extensor carpi radialis brevis branch of radial nerve, and flexor carpi radialis branch of median nerve to posterior interosseous nerve, for restoration of elbow, wrist, and finger extensions, respectively. Our experience confirmed functional elbow, wrist, and finger extensions in the patient. Triple nerve transfer restores functions of the upper limb in patients with debilitating radial nerve palsy after blunt injuries. Copyright © 2017 Elsevier Inc. All rights reserved.

SU-F-T-196: Hypo-Fractionation with Intensity Modulated Proton Therapy for Unilateral Metallic Prosthesis Prostate Cancer Patients

Energy Technology Data Exchange (ETDEWEB)

Rana, S; Park, S [McLaren Proton Therapy Center, Karmanos Cancer Institute at McLaren-Flint, Flint, MI (United States); Zheng, Y [Procure Proton Therapy Center, Oklahoma City, OK (United States); Zhang, Y [University of Cincinnati Medical Center, Liberty Township, OH (United States); Pokharel [21st Century Oncology, Estero, FL (United States); Cheng, C [Vantage Oncology, West Hills, CA (United States)

2016-06-15

Purpose: The purpose of this study is to investigate the dosimetric feasibility of hypo-fractionated intensity modulated proton therapy (IMPT) for unilateral metallic prosthesis prostate cancer patients based on proton collaborative group (PCG)-GU002-10 (NCT01230866) protocol criteria. Methods: A total of five unilateral metallic prosthesis prostate cancer cases were included in this retrospective study. For each case, IMPT plans were generated for treatment to be delivered with 7.6 Gy[RBE] per fraction in 5 fractions per week for a total dose of 38 Gy(RBE). Each plan was generated using two anterior-oblique beams and one lateral beam. Treatment plans were optimized with an objective meeting PCG-GU002-10 (NCT01230866) protocol criteria: (i) planning target volume (PTV): D99.5% > 36.1 Gy[RBE], (ii) rectum: V24 < 35%, V33.6 < 10%, (iii) bladder: V39 < 8 cc, and (iv) femoral head: V23 < 1cc. Results: All five cases satisfied PTV D99.5% (average=36.82 Gy[RBE]; range, 36.36–37.13 Gy[RBE]). PTV D95% ranged from 36.66 Gy[RBE] to 38.65 Gy[RBE] and PTV V100 ranged from 95.47% to 97.95%. For the rectum, V24 was less than 35% (average=14.07 Gy[RBE]; range, 6.22–18.42%, whereas V33.6 Gy[RBE] was less than 10% (average=6.83; range, 3.06 – 9.15%). Rectal mean dose ranged from 4.22 Gy[RBE] to 9.97 Gy[RBE]. For the bladder, V39 was found to be less than 8 cc (average=3.69 cc; range, 0.19–7.68 cc). Bladder mean dose ranged from 4.22 Gy[RBE] to 18.83 Gy[RBE]. For the femoral head, V23 was 0 in all five cases. Conclusion: All five unilateral metallic prosthesis prostate cancer IMPT plans generated with one lateral and two anterior-oblique beams satisfied the dosimetric criteria of PCG-GU002-10 (NCT01230866) protocol.

Control and Evaluation of a Powered Transfemoral Prosthesis for Stair Ascent.

Science.gov (United States)

Ledoux, Elissa D; Goldfarb, Michael

2017-07-01

This paper assesses the metabolic effort exerted by three transfemoral amputees, when using a powered knee and ankle prosthesis for stair ascent, relative to ascending stairs with passive knee and ankle prostheses. The paper describes a controller that provides step-over stair ascent behavior reflective of healthy stair ascent biomechanics, and describes its implementation in a powered prosthesis prototype. Stair ascent experiments were performed with three unilateral transfemoral amputee subjects, comparing the oxygen consumption required to ascend stairs using the powered prosthesis (with a step-over gait), relative to using their daily-use energetically passive prostheses (with a step-to gait). Results indicate on average a 24% reduction in oxygen consumption and a 30% reduction in stair ascent timewhen using the powered prosthesis, relative to when using the passive prostheses. All subjects expressed a strong preference for ascending stairs using the powered prosthesis.

Prosthetic rehabilitation of large mid-facial defect with magnet-retained silicone prosthesis

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Kirti Jajoo Shrivastava

2015-01-01

Full Text Available Rehabilitation of maxillofacial defect patients is a challenging task. The most common prosthetic treatment problem with such patients is, getting adequate retention, stability, and support. In cases of large maxillofacial defect, movement of the prosthesis is inevitable. The primary objectives in rehabilitating the maxillofacial defect patients are to restore the function of mastication, deglutition, speech, and to achieve normal orofacial appearance. This clinical report describes maxillofacial prosthetic rehabilitation of large midfacial defect including orbit along with its contents, zygoma and soft tissues including half of the nose, cheeks, upper lip of left side, accompanying postsurgical microstomia and orofacial communication, which resulted from severe fungal infection mucormycosis. The defect in this case was restored with magnet retained two piece maxillofacial prosthesis having hollow acrylic resin framework and an overlying silicone facial prosthesis. The retention of prosthesis was further enhanced with the use of spectacles. This type of combination prosthesis enhanced the cosmesis and functional acceptability of prosthesis.

Function of obturator prosthesis after maxillectomy and prosthetic obturator rehabilitation

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Cheng Chen

2016-04-01

Full Text Available ABSTRACT INTRODUCTION: Maxillary defects are usually rehabilitated by a prosthetic obturator. OBJECTIVE: This study aimed to evaluate the functioning of obturators prosthesis in patients with unilateral defects after maxillectomy. METHODS: Of 49 patients, 28 underwent to maxillectomy as a result of tumor ablative surgery, and acquired unilateral maxillary defects. Evaluation of the function was performed by applying the Obturator Functional Scale (OFS. RESULTS: From a total of 49 patients, 28 were treated as follows: 9 with a conventional retained obturator prosthesis (COP, 11 (39% with an enhanced retentive obturator prosthesis with stud attachment (POP and 8 (28% with an enhanced retentive obturator prosthesis with magnetic attachment (POM. The mean OFS score was 80. Scores on functions of speech, swallowing and chewing reached statistical significances (p < 0.05 among these three subgroups. Comparing COP and MOP groups, the scores of OFS in the domains of "Speech-ability to speak in public" and "Swallowing-leakage with liquids" were significantly higher in AOP group. Comparing COP group, the scores of OFS in "Swallowing-leakage with solid" and "Chewing/eating" domains were increased significantly (p < 0.05 both in MOP and AOP groups. CONCLUSION: Obturator prosthesis improves oral function of patients after maxillary defects; the retention of the obturator prosthesis enhanced by the addition of attachments showed more benefits in oral function.

Testicular prosthesis: Patient satisfaction and sexual dysfunctions in testis cancer survivors

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Francesco Catanzariti

2016-10-01

Full Text Available Purpose: We studied patient satisfaction about sexual activity after prosthesis implantation using validated questionnaires with the aim to discover if testicular prosthesis could be responsible of sexual dysfunctions (erectile dysfunction or premature ejaculation. Materials and Methods: We evaluated a total of 67 men who underwent radical orchiectomy for testicular cancer and a silicon testicular prosthesis implantation from January 2008 to June 2014 at our Hospital. These patients completed 5 validated questionnaires the day before orchiectomy and 6 months after surgery: the International Index of Erectile Function 5 (IIEF5, the Premature Ejaculation Diagnostic Tool (PEDT, the Body Exposure during Sexual Activities Questionnaire (BESAQ, the Body-Esteem Scale and the Rosenberg Self- Esteem Scale. We also evaluated 6 months after surgery any defects of the prosthesis complained by the patients. Results: The questionnaires completed by patients didn’t show statistically significant changes for erectile dysfunction (p > 0.05 and premature ejaculation (p > 0.05. On the contrary the psychological questionnaires showed statistically significant change for the BESAQ (p < 0.001 and the Body Esteem Scale (p < 0.001, but not for the Rosenberg Self-Esteem Scale (p > 0,05. A total of 15 patients (22.37% were dissatisfied about the prosthesis: the most frequent complaint (8 patients; 11.94% was that the prosthesis was firmer than the normal testis. Conclusions: Testicular prosthesis implantation is a safe surgical procedure that should be always proposed before orchiectomy for cancer of the testis. The defects complained by patients with testicular prosthesis are few, they don’t influence sexual activity and they aren’t able to cause erectile dysfunction or premature ejaculation.

Use of Powered Prosthesis for Children with Upper Limb Deficiency at Hyogo Rehabilitation Center.

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Mitsunori Toda

Full Text Available There has been no research investigating the use of powered prosthetic for children in Japan.To gain better insight into the state of powered prosthesis usage and identify a ratio of rejection among children.Subjects were 37 unilateral below elbow amputees between the ages of 0 and 16 at the time of their first experienced fitting with a powered prosthesis at our Center. The information was collected from medical records and through face-to-face interviews, and we examined rejection rate and the factors affecting the use of powered prosthesis.The rate of discontinuation was 21.6% as 8 of the 37 children stopped using powered prosthesis. All of them were fitted their prosthesis after 2 years of age, and they rejected prosthesis between 5 to 19 years. We found that the level of amputation had no influence on the use of a powered prosthesis.Children fitted before 2 years of age tend to accept their powered prosthesis than those fitted after 2 years. Multidisciprinary team approach, adequate rehabilitation, detailed follow-up and involvement of parents are quite important for introducing powered prosthesis for children.

Changes in performance over time while learning to use a myoelectric prosthesis

NARCIS (Netherlands)

Bouwsema, Hanneke; van der Sluis, Corry K.; Bongers, Raoul M.

2014-01-01

Background: Training increases the functional use of an upper limb prosthesis, but little is known about how people learn to use their prosthesis. The aim of this study was to describe the changes in performance with an upper limb myoelectric prosthesis during practice. The results provide a basis

Design of a power-asymmetric actuator for a transtibial prosthesis.

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Bartlett, Harrison L; Lawson, Brian E; Goldfarb, Michael

2017-07-01

This paper presents the design and characterization of a power-asymmetric actuator for a transtibial prosthesis. The device is designed to provide the combination of: 1) joint locking, 2) high power dissipation, and 3) low power generation. This actuator functionality allows for a prosthesis to be designed with minimal mass and power consumption relative to a fully-powered robotic prosthesis while maintaining much of the functionality necessary for activities of daily living. The actuator achieves these design characteristics while maintaining a small form factor by leveraging a combination of electromechanical and hydraulic components. The design of the actuator is described herein, and results of an experimental characterization are provided that indicate that the actuator is capable of providing the functional capabilities required of an ankle prosthesis in a compact and lightweight package.

Cranioplasty prosthesis manufacturing based on reverse engineering technology

Science.gov (United States)

Chrzan, Robert; Urbanik, Andrzej; Karbowski, Krzysztof; Moskała, Marek; Polak, Jarosław; Pyrich, Marek

2012-01-01

Summary Background Most patients with large focal skull bone loss after craniectomy are referred for cranioplasty. Reverse engineering is a technology which creates a computer-aided design (CAD) model of a real structure. Rapid prototyping is a technology which produces physical objects from virtual CAD models. The aim of this study was to assess the clinical usefulness of these technologies in cranioplasty prosthesis manufacturing. Material/Methods CT was performed on 19 patients with focal skull bone loss after craniectomy, using a dedicated protocol. A material model of skull deficit was produced using computer numerical control (CNC) milling, and individually pre-operatively adjusted polypropylene-polyester prosthesis was prepared. In a control group of 20 patients a prosthesis was manually adjusted to each patient by a neurosurgeon during surgery, without using CT-based reverse engineering/rapid prototyping. In each case, the prosthesis was implanted into the patient. The mean operating times in both groups were compared. Results In the group of patients with reverse engineering/rapid prototyping-based cranioplasty, the mean operating time was shorter (120.3 min) compared to that in the control group (136.5 min). The neurosurgeons found the new technology particularly useful in more complicated bone deficits with different curvatures in various planes. Conclusions Reverse engineering and rapid prototyping may reduce the time needed for cranioplasty neurosurgery and improve the prosthesis fitting. Such technologies may utilize data obtained by commonly used spiral CT scanners. The manufacturing of individually adjusted prostheses should be commonly used in patients planned for cranioplasty with synthetic material. PMID:22207125

Radial Head Subluxation: Possible Effective Factors on Time to Re-use the Affected Limb

Directory of Open Access Journals (Sweden)

Farhad Heydari

2018-01-01

Full Text Available Introduction: Radial head subluxation (RHS is a common disorder in children. Although it is not accompanied by any important short- or long-term sequel, it could make the parents worried about. Objective: The purpose of this study was to determine the possible effective factors that may influence time to use the affected limb. Methods: This cross-sectional study was conducted prospectively during the years 2014 to 2016. All children under the age of 6 years who visited the emergency department (ED and were diagnosed as having RHS were eligible. The patients’ baseline information was recorded. After the reduction, the time until the affected arm use returned was recorded. The possible relationship between the baseline data and time to re-use the affected limb was assessed. Results: During the study period, 112 children with a mean age of 30.18 ± 18.18 months were evaluated (53% male. Among the children who visited the ED during the first 4 hours and thereafter, 84% and 60%, respectively, re-used their limb in less than 10 minutes after reduction (p = 0.004. Also, 55% of children less than or equal to 24 months and 89% over the age of 24 months re-used the arm in 10 minutes (p < 0.001. The success rate of the first reduction maneuver was significantly lower in children with a recurrent dislocation (p = 0.001. Conclusion: It is likely that age less than or equal to 24 months and ED visit after 4 hours of the event lead to a longer duration for re-using the affected arm following reduction.

Anatomic humeral head replacement with a press-fit prosthesis: An in vivo radiographic study

Directory of Open Access Journals (Sweden)

Bryan Vopat

2017-10-01

Full Text Available Successful total shoulder arthroplasty is, in part, dependent on anatomic reconstruction of the glenohumeral joint. The purpose of this study was to evaluate the post-operative anatomy of total shoulder arthroplasty with an anatomic implant design in patients with primary glenohumeral osteoarthritis and compare it to published normative anatomic measurements. Fifty-one patients (56 shoulders with primary glenohumeral osteoarthritis were treated with a press-fit humeral component as part of a total shoulder arthroplasty (Aequalis, Tornier, Edina, Minnesota. Analysis of postoperative true anterior posterior radiographs was performed with use of a custom software algorithm. The mean humeral inclination (head-shaft angle, mean humeral implant anatomical humeral axis, mean greater tuberosity height, and mean humeral head center offset (medial offset were 135.4±5.1°, 1.73±1.7°, 6.9±2.4 mm, and 3.8±1.8 mm, respectively. All parameters were within the ranges reported in the literature for normal shoulders except the mean humeral head center offset, which was less than reported in the literature. Anatomic parameters of a total shoulder arthroplasty can be achieved with an anatomically designed, modular adaptable press-fit design. Reduced medial humeral head center offset was likely dependent upon implant specific design parameters.

Function of obturator prosthesis after maxillectomy and prosthetic obturator rehabilitation.

Science.gov (United States)

Chen, Cheng; Ren, Wenhao; Gao, Ling; Cheng, Zheng; Zhang, Linmei; Li, Shaoming; Zhi, Pro Ke-qian

2016-01-01

Maxillary defects are usually rehabilitated by a prosthetic obturator. This study aimed to evaluate the functioning of obturators prosthesis in patients with unilateral defects after maxillectomy. Of 49 patients, 28 underwent to maxillectomy as a result of tumor ablative surgery, and acquired unilateral maxillary defects. Evaluation of the function was performed by applying the Obturator Functional Scale (OFS). From a total of 49 patients, 28 were treated as follows: 9 with a conventional retained obturator prosthesis (COP), 11 (39%) with an enhanced retentive obturator prosthesis with stud attachment (POP) and 8 (28%) with an enhanced retentive obturator prosthesis with magnetic attachment (POM). The mean OFS score was 80. Scores on functions of speech, swallowing and chewing reached statistical significances (p<0.05) among these three subgroups. Comparing COP and MOP groups, the scores of OFS in the domains of "Speech-ability to speak in public" and "Swallowing-leakage with liquids" were significantly higher in AOP group. Comparing COP group, the scores of OFS in "Swallowing-leakage with solid" and "Chewing/eating" domains were increased significantly (p<0.05) both in MOP and AOP groups. Obturator prosthesis improves oral function of patients after maxillary defects; the retention of the obturator prosthesis enhanced by the addition of attachments showed more benefits in oral function. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Design and Characterization of a Quasi-Passive Pneumatic Foot-Ankle Prosthesis.

Science.gov (United States)

Lee, Jeffrey D; Mooney, Luke M; Rouse, Elliott J

2017-07-01

The majority of commercially available passive prosthetic feet are not capable of providing joint mechanics that match that of the intact human ankle. Due to their cantilever design, their stiffness characteristics contrast with what has been observed in the biological ankle, namely, an increase in stiffness during the stance phase of walking. In this paper, we introduce the design and control of a pneumatic foot-ankle prosthesis that attempts to provide biomimetic mechanics. The prosthesis is comprised of a pneumatic cylinder in series with a fiberglass leaf spring, and a solenoid valve to control the flow of air between the two sides of the cylinder. The solenoid valve acts as a mechanical clutch, enabling resetting of the ankle's equilibrium position. By adjusting the pressure inside the cylinder, the prosthesis can be customized to provide a range of ankle mechanics. A mechanical testing machine is used to compare the torque-angle curve of the pneumatic prosthesis with a low-profile passive prosthetic foot. Finally, data are presented of one transtibial amputee walking with the prosthesis at 1.2 m/s. The testing shows that the pneumatic prosthesis is capable of providing an appropriate range of motion as well a maximum torque of 94 Nm, while returning approximately 11.5 J of energy.

Doppler derived gradient of ST Jude Mechanical Prosthesis, early postoperative assessment

International Nuclear Information System (INIS)

Shaikh, A.H.; Hanif, B.; Adil, A.; Hashimi, S.; Qazi, H.A.; Mujtaba, I.

2010-01-01

Objective: To determine the doppler derived mean gradients of St Jude mechanical prosthesis in early postoperative period in patients undergoing valve replacement at a tertiary care cardiac centre. Methods: Medical records of 190 consecutive patients who underwent 233 mitral, aortic or dual (mitral and aortic) valve replacement by St Jude bileaflet mechanical prosthesis at Tabba Heart Institute, between March 2006 to December 2008 were reviewed. Doppler derived mean gradients were assessed predischarge and recorded. Results: There were 98 (51.5%) males and 92 (48.5%) females in the study cohort. The mean age was 40 +- 14 years. Of the total, 101 (53%) had mitral, 46 (24.2%) had aortic and 43 (22.6%) patients had dual valve replacement. Doppler derived mean gradient was assessed across 144 mitral and 89 aortic St Jude mechanical prosthesis. Doppler derived mean gradient for St Jude mitral prosthesis was 3.5 mm Hg and for St Jude aortic prosthesis was 10.2 mm Hg. Conclusions: The study determines baseline gradients across mitral and aortic St Jude mechanical prosthesis in our population. These can be used as reference gradients to assess St Jude prosthetic valve function in patients who did not have early postoperative doppler assessment. (author)

The reverse shoulder prosthesis: a review of imaging features and complications

Energy Technology Data Exchange (ETDEWEB)

McFarland, Edward G.; Sanguanjit, Prakasit; Tasaki, Atsushi [Johns Hopkins University, Department of Orthopedic Surgery, Lutherville, MD (United States); Keyurapan, Ekavit [Mahidol University, Department of Orthopaedic Surgery, Bangkok (Thailand); Fishman, Elliot K.; Fayad, Laura M. [Johns Hopkins Medical Institutions, Johns Hopkins University, Department of Radiology and Radiological Sciences, Baltimore, MD (United States)

2006-07-15

The reverse shoulder prosthesis is a prosthesis that has been in clinical use in Europe since 1985 and was approved for use in the United States in 2004. This unique prosthesis has a baseplate attached to the glenoid, which holds a spherical component, while the humeral component includes a polyethylene insert that is flat. This design is the ''reverse'' configuration of that seen with a conventional arthroplasty, in which the spherical component is part of the humeral component. The indications for the reverse prosthesis are: (1) painful arthritis associated with irreparable rotator cuff tears (cuff tear arthropathy), (2) failed hemiarthroplasty with irreparable rotator cuff tears, (3) pseudoparalysis due to massive, irreparable rotator cuff tears, (4) some reconstructions after tumor resection, and (5) some fractures of the shoulder not repairable or reconstructable with other techniques. This prosthesis can produce a significant reduction in pain and some improvement in function for most of the indications mentioned. However, the unique configuration and the challenge of its insertion can result in a high incidence of a wide variety of unusual complications. Some of these complications, such as dislocation of the components, are similar to conventional shoulder replacement. Other complications, such as notching of the scapula and acromial stress fractures, are unique to this prosthesis. (orig.)

The reverse shoulder prosthesis: a review of imaging features and complications

International Nuclear Information System (INIS)

McFarland, Edward G.; Sanguanjit, Prakasit; Tasaki, Atsushi; Keyurapan, Ekavit; Fishman, Elliot K.; Fayad, Laura M.

2006-01-01

The reverse shoulder prosthesis is a prosthesis that has been in clinical use in Europe since 1985 and was approved for use in the United States in 2004. This unique prosthesis has a baseplate attached to the glenoid, which holds a spherical component, while the humeral component includes a polyethylene insert that is flat. This design is the ''reverse'' configuration of that seen with a conventional arthroplasty, in which the spherical component is part of the humeral component. The indications for the reverse prosthesis are: (1) painful arthritis associated with irreparable rotator cuff tears (cuff tear arthropathy), (2) failed hemiarthroplasty with irreparable rotator cuff tears, (3) pseudoparalysis due to massive, irreparable rotator cuff tears, (4) some reconstructions after tumor resection, and (5) some fractures of the shoulder not repairable or reconstructable with other techniques. This prosthesis can produce a significant reduction in pain and some improvement in function for most of the indications mentioned. However, the unique configuration and the challenge of its insertion can result in a high incidence of a wide variety of unusual complications. Some of these complications, such as dislocation of the components, are similar to conventional shoulder replacement. Other complications, such as notching of the scapula and acromial stress fractures, are unique to this prosthesis. (orig.)

Association between dental prosthesis need, nutritional status and quality of life of elderly subjects

DEFF Research Database (Denmark)

Pillai, Rajath; Mathur, Vijay Prakash; Jain, Veena

2015-01-01

clinic were recruited in the study. Mini-nutritional assessment (MNA), geriatric oral health assessment (GOHAI) indices, prosthesis need according to WHO criteria, and prosthesis want was recorded along with age, gender, socioeconomic status and posterior occluding pair. RESULTS: Significant associations......To determine the effect of prosthesis need on nutritional status and oral health-related quality of life (OHrQoL) in elderly and to check the disparity between prosthesis need and prosthesis want in the Indian elderly. METHODS: A total of 946 geriatric participants reporting to a geriatric medicine...

Smartphone supported upper limb prosthesis

Directory of Open Access Journals (Sweden)

Hepp D.

2015-09-01

Full Text Available State of the art upper limb prostheses offer up to six active DoFs (degrees of freedom and are controlled using different grip patterns. This low number of DoFs combined with a machine-human-interface which does not provide control over all DoFs separately result in a lack of usability for the patient. The aim of this novel upper limb prosthesis is both offering simplified control possibilities for changing grip patterns depending on the patients’ priorities and the improvement of grasp capability. Design development followed the design process requirements given by the European Medical Device Directive 93/42 ECC and was structured into the topics mechanics, software and drive technology. First user needs were identified by literature research and by patient feedback. Consequently, concepts were evaluated against technical and usability requirements. A first evaluation prototype with one active DoF per finger was manufactured. In a second step a test setup with two active DoF per finger was designed. The prototype is connected to an Android based smartphone application. Two main grip patterns can be preselected in the software application and afterwards changed and used by the EMG signal. Three different control algorithms can be selected: “all-day”, “fine” and “tired muscle”. Further parameters can be adjusted to customize the prosthesis to the patients’ needs. First patient feedback certified the prosthesis an improved level of handling compared to the existing devices. Using the two DoF test setup, the possibilities of finger control with a neural network are evaluated at the moment. In a first user feedback test, the smartphone based software application increased the device usability, e.g. the change within preselected grip patterns and the “tired muscle” algorithm. Although the overall software application was positively rated, the handling of the prosthesis itself needs to be proven within a patient study to be

Effect of silicone gel breast prosthesis on electron and photon dose distributions

International Nuclear Information System (INIS)

Krishnan, L.; St George, F.J.; Mansfield, C.M.; Krishnan, E.C.

1983-01-01

The effect of a silicone gel breast prosthesis on the absorbed dose distribution of 9-20 MeV electron beams and 1.25-15 MV photon beams was studied. Compared to water measurements, at depths smaller than the practical range of the electron beams, the central axis depth dose values below the prosthesis were lower for all energies by as much as 3.5%. However, at depths near the practical range, the central axis depth dose values for the prosthesis were greater than that of water by as much as 33%. Since this occurs near the end of the electron range, the resultant difference may not be clinically significant. Results of the effect of breast prosthesis on photon depth dose distributions reveal that no clinically significant perturbation is produced by the breast prosthesis using Co-60, 6- and 15-MV radiations

Fabrication of custom made ocular prosthesis with three different ...

African Journals Online (AJOL)

Loss of eye has a bad effect on the psychology of the patient. Eye prosthesis is fabricated to regain the patient's confidence by meticulous replacement of the missing eye. Immediate fitting of an anophthalmic socket with an artificial eye may not always be possible, and a delayed prosthesis delivery may result in settling and ...

Simplified technique for orbital prosthesis fabrication: a clinical report.

Science.gov (United States)

Veerareddy, Chandrika; Nair, K Chandrasekharan; Reddy, G Ramaswamy

2012-10-01

Loss of orbital content can cause functional impairment, disfigurement of the face, and psychological distress. Rehabilitation of an orbital defect is a complex task, and if reconstruction by plastic surgery is not possible or not desired by the patient, the defect can be rehabilitated by an orbital prosthesis. The prosthetic rehabilitation in such cases depends on the precisely retained, user-friendly removable maxillofacial prosthesis. Many times, making an impression of the orbital area with an accurate record of surface details can be a difficult procedure. The critical areas are making a facial moulage, mold preparation, and attaching the retention device, particularly when eyeglass frames are used. This case focuses on these hindrance factors. A simple basket was used for the impression tray to obtain the facial moulage. A putty mold was used, and attachment of the prosthesis to a retention device was accomplished with positional distance. This method proves to be an economical and simple way of making an orbital prosthesis. © 2012 by the American College of Prosthodontists.

[Rehabilitation by hollow obturator prosthesis immediately after total maxillectomy for malignant tumor].

Science.gov (United States)

Li, Xiao-ye; Yan, Ai-hui; Hao, Shuai; Li, Wei; Jiang, Xue-jun; Lu, Li; Qin, Xing-jun; Yan, Hai-xin

2011-05-01

The feasibility and clinical effects of hollow obturator prosthesis for the repair of maxillofacial defect immediately after maxillectomy for cancer were assessed. Thirteen patients with T3-4aN0M0 maxillary neoplasm were treated by the prostheses immediately after maxillectomy. According to the 3D-CT reconstruction of nasal sinus, the 3D stereoscopic prototype was constructed before the surgery. Simulating surgery with Surgicare 5.0 software and then the prosthesis 3D stereoscopic model was shaped. The prosthesis was made quickly and precisely with methacrylate resins according to the model and the print mold before surgery, with supplementary tooth at the bottom of prosthesis. In the surgery, the prosthesis was installed instantly after maxillectomy. The patients were followed up at 1, 3 and 6 month after the surgery, respectively. The facial features and the pronunciation clarity were examined and the questionnaires were carried out in the patients, with comparation by paired t-test. The hollow obturator prosthesis would be replaced by permanent prosthesis made of methacrylate resins at 6 month after the surgery. The hollow obturator prostheses were installed accurately and maxillofacial defects were repaired immediately after maxillectomy in the 13 patients. Postoperative follow-up showed there were significant differences in eyeball sagging (t = 4.67, P maxillectomy can improve survival quality of patient.

Treatment of femoral neck fracture by Moore Prosthesis in Cotonou ...

African Journals Online (AJOL)

Treatment of femoral neck fracture by Moore Prosthesis in Cotonou. AHM Akue, M Lawson, S Madougou, R Zannou, J Padonou. Abstract. Keywords: Benin; hip; Moore prosthesis; results. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Analysis of the mechanical behavior of the Nijdam voice prosthesis

NARCIS (Netherlands)

Verkerke, GJ; deVries, MP; Schutte, HK; vandenHoogen, FJA; Rakhorst, G

1997-01-01

The valveless Nijdam prosthesis is a new voice prosthesis for laryngectomized patients using tracheoesophageal speech. An ''umbrella-like hat'' covers the esophageal side of the tracheoesophageal fistula and is deformed during speech by air pressure. To decrease pressure loss during speech, a good

Custom-made silicone hand prosthesis: A case study.

Science.gov (United States)

Nayak, S; Lenka, P K; Equebal, A; Biswas, A

2016-09-01

Up to now, a cosmetic glove was the most common method for managing transmetacarpal (TMC) and carpometacarpal (CMC) amputations, but it is devoid of markings and body color. At this amputation level, it is very difficult to fit a functional prosthesis because of the short available length, unsightly shape, grafted skin, contracture and lack of functional prosthetic options. A 30-year-old male came to our clinic with amputation at the 1st to 4th carpometacarpal level and a 5th metacarpal that was projected laterally and fused with the carpal bone. The stump had grafted skin, redness, and an unhealed suture line. He complained of pain projected over the metacarpal and suture area. The clinical team members decided to fabricate a custom-made silicone hand prosthesis to accommodate the stump, protect the grafted skin, improve the hand's appearance and provide some passive function. The custom silicone hand prosthesis was fabricated with modified flexible wires to provide passive interphalangeal movement. Basic training, care and maintenance instructions for the prosthesis were given to the patient. The silicone hand prosthesis was able to restore the appearance of the lost digits and provide some passive function. His pain (VAS score) was reduced. Improvement in activities of daily living was found in the DASH questionnaire and Jebsen-Taylor Hand Function test. A silicone glove is a good option for more distal amputations, as it can accommodate any deformity, protect the skin, enhance the appearance and provide functional assistance. This case study provides a simple method to get passively movable fingers after proximal hand amputation. Copyright © 2016. Published by Elsevier Masson SAS.

Mastication improvement after partial implant-supported prosthesis use.

Science.gov (United States)

Gonçalves, T M S V; Campos, C H; Gonçalves, G M; de Moraes, M; Rodrigues Garcia, R C M

2013-12-01

Partially edentulous patients may be rehabilitated by the placement of removable dental prostheses, implant-supported removable dental prostheses, or partial implant fixed dental prostheses. However, it is unclear the impact of each prosthesis type over the masticatory aspects, which represents the objective of this paired clinical trial. Twelve patients sequentially received and used each of these 3 prosthesis types for 2 months, after which maximum bite force was assessed by a strain sensor and food comminution index was determined with the sieving method. Masseter and temporal muscle thicknesses during rest and maximal clenching were also evaluated by ultrasonography. Each maxillary arch received a new complete denture that was used throughout the study. Data were analyzed by analysis of variance for repeated measures, followed by the Tukey test (p mastication, and the magnitude of this effect was related to prosthesis type.

Radial-velocity variations in Alpha Ori, Alpha Sco, and Alpha Her

International Nuclear Information System (INIS)

Smith, M.A.; Patten, B.M.; Goldberg, L.

1989-01-01

Radial-velocity observations of Alpha Ori, Alpha Sco A, and Alpha Her A are used to study radial-velocity periodicities in M supergiants. The data refer to several metallic lines in the H-alpha region and to H-alpha itself. It is shown that Alpha Ori and Alpha Sco A have cycle lengths of about 1 yr and semiamplitudes of 2 km/s. It is suggested that many semiregular red supergiant varibles such as Alpha Ori may be heading toward chaos. All three stars show short-term stochastic flucutations with an amplitude of 1-2 km/s. It is found that the long-term variability of H-alpha velocities may be a consequence of intermittent failed ejections. 58 refs

Structural valve deterioration in the Mitroflow biological heart valve prosthesis

DEFF Research Database (Denmark)

Issa, Issa Farah; Poulsen, Steen Hvitfeldt; Waziri, Farhad

2018-01-01

OBJECTIVES: Concern has been raised regarding the long-term durability of the Mitroflow biological heart valve prosthesis. Our aim was to assess the incidence of structural valve degeneration (SVD) for the Mitroflow bioprosthesis in a nationwide study in Denmark including all patients alive......: A total of 173 patients were diagnosed with SVD by echocardiography. Of these, 64 (11%) patients had severe SVD and 109 (19%) patients moderate SVD. Severe SVD was associated with the age of the prosthesis and small prosthesis size [Size 21: hazard ratio (95% confidence interval, CI) 2.72 (0.97-8.56), P...

Prosthesis infections after orthopedic joint replacement: the possible role of bacterial biofilms

Directory of Open Access Journals (Sweden)

Zhijun Song

2013-06-01

Full Text Available Prosthesis-related infection is a serious complication for patients after orthopedic joint replacement, which is currently difficult to treat with antibiotic therapy. Consequently, in most cases, removal of the infected prosthesis is the only solution to cure the infection. It is, therefore, important to understand the comprehensive interaction between the microbiological situation and the host immune responses that lead to prosthesis infections. Evidence indicates that prosthesis infections are actually biofilm-correlated infections that are highly resistant to antibiotic treatment and the host immune responses. The authors reviewed the related literature in the context of their clinical experience, and discussed the possible etiology and mechanism leading to the infections, especially problems related to bacterial biofilm, and prophylaxis and treatment of infection, including both microbiological and surgical measures. Recent progress in research into bacterial biofilm and possible future treatment options of prosthesis-related infections are discussed.

Outcome of total knee arthroplasty with insall burstein-11 prosthesis

International Nuclear Information System (INIS)

Siddiq, M.Z.; Qayum, H.

2006-01-01

Patients with severe degenerative knee joint disease often require knee arthroplasty to reduce pain, improve stability and restore function. Insall Burstein II prosthesis is posteriorly stabilized condylar prosthesis, which provide posterior cruciate ligament substitution. It was designed to improve range of motion, stair climbing ability and to prevent posterior subluxation. Evaluate the functional outcome of total knee arthroplasty with IB II prosthesis and Evaluate the alignment of prosthetic components by radiological parameters and its correlation with functional outcome. Sixty knees of sixty patients were replaced by using Insall Burstein II prosthesis. Postoperative radiographs were evaluated for alignment of knee and prosthetic components by criteria selected from knee society roentogenographic evaluation system. Functional outcome was evaluated by rationale of knee society knee rating system. Prosthetic component was aligned in 93% and mal-alignment in 7% of the cases. There was significant improvement in functions core from mean score 33.83 +-15.5 to 59.5+-17.7 and knee score from 37 +- 12.5 to 76.4 +-2.2. Postoperative functional score was found correlated with alignment significantly. Conclusion: Total knee arthroplasty with I-B-II prosthesis is a safe durable and predictable procedure with proper surgical technique and expertise good alignment and satisfactory functional out come can be achieved. (author)

Prosthetic management of mid-facial defect with magnet-retained silicone prosthesis

OpenAIRE

Buzayan, M. M.

2014-01-01

Background and aim: Mid-facial defect is one of the most disfiguring and impairing defects. A design of prosthesis that is aesthetic and stable can be precious to a patient who has lost part of his face due to surgical excision. Prosthesis can restore the patients' self-esteem and confidence, which affects the patients and their life style. The aim of this case report is to describe a technique of mid-facial silicone prosthesis fabrication. Technique: To provide an aesthetic and stable facial...

Experimental investigation of the stability of a moving radial liquid sheet

Science.gov (United States)

Paramati, Manjula; Tirumkudulu, Mahesh

2013-11-01

Experiments were conducted to understand the stability of moving radial liquid sheets formed by the head-on impingement of two co-linear water jets using laser induced fluorescence technique (LIF). Acoustic sinusoidal fluctuations were introduced at the jet impingement point and we measured the displacement of the center line of the liquid sheet (sinuous mode) and the thickness variation (varicose mode) of the disturbed liquid sheet. Our experiments show that the sinuous disturbances grow as they are convected outward in the radial direction even in the smooth regime (We theory by Tirumkudulu and Paramati (Communicated to Phys. Of Fluids, 2013) which accounts for the inertia of the liquid phase and the surface tension force in a radial liquid sheet while neglecting the inertial effects due to the surrounding gas phase. The authors acknowledge the financial assistance from Indo-French Center for Pro- motion of Advanced Research and also Indian institute of technology Bombay.

Acetabular prosthesis: Proff of migration with ruler and pencil?

International Nuclear Information System (INIS)

Diederichs, C.G.; Fischer, U.; Vosshenrich, R.

1993-01-01

Conventional X-ray films were made with varying degrees of tilt of a pelvic phantom containing an acetabular prosthesis. The position of the prosthesis was then reconstructed graphically. The measurement errors were calculated and an estimate was made for the tilt. There is a linear correlation between the measurement error and the tilt of the prosthesis. Therefore a tilt dependent maximum error can be calculated. This error is very small for small degrees of tilt, so that acetabular migration can in this instance be evaluated with greater confidence than with other graphical methods. The error also correlates with the determination of the selected region of the acetabulum, but not with the position of the central focus spot or image magnification. (orig.) [de

Rehabilitation of orbital cavity after orbital exenteration using polymethyl methacrylate orbital prosthesis

Directory of Open Access Journals (Sweden)

Sumeet Jain

2016-01-01

Full Text Available Squamous cell carcinoma of the eyelid is the second most common malignant neoplasm of the eye with the incidence of 0.09 and 2.42 cases/100 000 people. Orbital invasion is a rare complication but, if recognized early, can be treated effectively with exenteration. Although with advancements in technology such as computer-aided design and computer-aided manufacturing, material science, and retentive methods like implants, orbital prosthesis with stock ocular prosthesis made of methyl methacrylate retained by anatomic undercuts is quiet effective and should not be overlooked and forgotten. This clinical report describes prosthetic rehabilitation of two male patients with polymethyl methacrylate resin orbital prosthesis after orbital exenteration, for squamous cell carcinoma of the upper eyelid. The orbital prosthesis was sufficiently retained by hard and soft tissue undercuts without any complications. The patients using the prosthesis are quite satisfied with the cosmetic results and felt comfortable attending the social events.

Comparison of Exposure in the Kaplan Versus the Kocher Approach in the Treatment of Radial Head Fractures.

Science.gov (United States)

Barnes, Leslie Fink; Lombardi, Joseph; Gardner, Thomas R; Strauch, Robert J; Rosenwasser, Melvin P

2018-01-01

The aim of this study was to compare the complete visible surface area of the radial head, neck, and coronoid in the Kaplan and Kocher approaches to the lateral elbow. The hypothesis was that the Kaplan approach would afford greater visibility due to the differential anatomy of the intermuscular planes. Ten cadavers were dissected with the Kaplan and Kocher approaches, and the visible surface area was measured in situ using a 3-dimensional digitizer. Six measurements were taken for each approach by 2 surgeons, and the mean of these measurements were analyzed. The mean surface area visible with the lateral collateral ligament (LCL) preserved in the Kaplan approach was 616.6 mm 2 in comparison with the surface area of 136.2 mm 2 visible in the Kocher approach when the LCL was preserved. Using a 2-way analysis of variance, the difference between these 2 approaches was statistically significant. When the LCL complex was incised in the Kocher approach, the average visible surface area of the Kocher approach was 456.1 mm 2 and was statistically less than the Kaplan approach. The average surface area of the coronoid visible using a proximally extended Kaplan approach was 197.8 mm 2 . The Kaplan approach affords significantly greater visible surface area of the proximal radius than the Kocher approach.

Multidisciplinary approach for in-deep assessment of joint prosthesis failure.

Science.gov (United States)

Tessarolo, F; Caola, I; Piccoli, F; Dorigotti, P; Demattè, E; Molinari, M; Malavolta, M; Barbareschi, M; Caciagli, P; Nollo, G

2009-01-01

In spite of advancement in biomaterials and biomechanics, in development of new osteo-integrative materials and coatings, and in macro- micro- component design, a non negligible fraction of the implanted prosthesis fails before the expected lifetime. A prospective observational clinical study has been conducted to define and apply a set of experimental techniques to in-deep assess the failure of joint prosthesis. Microbiological, histological and micro-structural techniques were implemented to specifically address phenomena occurring at the tissue-implant interface. Results obtained from 27 cases of prosthetic joint failure are discussed in terms of sensitivity and specificity. A procedural flow-chart is finally proposed for the assessment of joint prosthesis failure.

Utilization of penile prosthesis and male incontinence prosthetics in Saudi Arabia.

Science.gov (United States)

Alwaal, Amjad; Al-Sayyad, Ahmad J

2017-01-01

Erectile dysfunction is a prevalent disease affecting over 50% of men between the ages of 40 and 70 years. Penile prosthesis represents the end of the line treatment when other less invasive therapies fail or are contraindicated. Male stress urinary incontinence can significantly diminish quality of life and lead to embarrassment and social withdrawal. Surgical therapies, such as male urethral slings and artificial urinary sphincters (AUS), are considered effective and safe treatments for male stress incontinence. No data exist on the utilization of penile prosthesis or male incontinence surgical treatment in Saudi Arabia. Generally, urological prosthetic surgery is performed either in private hospitals or in government hospitals. Our aim was to assess the trend of penile prosthesis and male incontinence device utilization in Saudi Arabia. We utilized sales' data of penile prosthetics, male slings, and AUS from the only two companies selling these devices in Saudi Arabia (AMS ® and Coloplast ® ), from January 2013 to December 2016. There were 2599 penile prosthesis implantation procedures done in the study period, with 67% of them performed in private institutions. There was a progressively increased use of penile prosthetics which nearly doubled from 2013 to 2016. The main type of prosthesis utilized was the semirigid type 70% versus 11% of the 2-piece inflatable and 17% of the 3-piece inflatable device. Only 10 slings and 31 AUS were inserted during the same study period. There is an increased utilization of penile prosthetics in Saudi Arabia. The private sector performs the majority of penile prosthesis procedures, and most of them are of the semirigid type. The governmental sector is more likely to perform inflatable penile prosthesis and male incontinence device procedures. Male incontinence prosthetics' use is very limited in Saudi Arabia.

Percutaneous Revision of a Testicular Prosthesis is Safe, Cost-effective, and Provides Good Patient Satisfaction

Directory of Open Access Journals (Sweden)

Eugene B. Cone

2015-09-01

Full Text Available Office-based percutaneous revision of a testicular prosthesis has never been reported. A patient received a testicular prosthesis but was dissatisfied with the firmness of the implant. In an office setting, the prosthesis was inflated with additional fluid via a percutaneous approach. Evaluated outcomes included patient satisfaction, prosthesis size, recovery time, and cost savings. The patient was satisfied, with no infection, leak, or complication after more than 1 year of follow-up, at significantly less cost than revision surgery. Percutaneous adjustment of testicular prosthesis fill-volume can be safe, inexpensive, and result in good patient satisfaction.

A direct bonded fixed partial dental prosthesis: A clinical report

OpenAIRE

Tanoue, Naomi; Tanaka, Takuo

2015-01-01

A direct bonded fixed partial dental prosthesis, with a composite resin denture tooth as a pontic, a tri-n-butylborane initiated adhesive resin, and screw posts for reinforcement, was still functioning after an observation period of 20 years. The prosthesis was found to be reliable for long-term clinical use when chemically and mechanically reinforced.

Perforator anatomy of the radial forearm free flap versus the ulnar forearm free flap for head and neck reconstruction.

Science.gov (United States)

Hekner, D D; Roeling, T A P; Van Cann, E M

2016-08-01

The aim of this study was to investigate the vascular anatomy of the distal forearm in order to optimize the choice between the radial forearm free flap and the ulnar forearm free flap and to select the best site to harvest the flap. The radial and ulnar arteries of seven fresh cadavers were injected with epoxy resin (Araldite) and the perforating arteries were dissected. The number of clinically relevant perforators from the radial and ulnar arteries was not significantly different in the distal forearm. Most perforators were located in the proximal half of the distal one third, making this part probably the safest location for flap harvest. Close to the wrist, i.e. most distally, there were more perforators on the ulnar side than on the radial side. The ulnar artery stained 77% of the skin surface area of the forearm, showing the ulnar forearm free flap to be more suitable than the radial forearm free flap for the restoration of large defects. Copyright © 2016 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Rehabilitation of single finger amputation with customized silicone prosthesis

OpenAIRE

Yadav, Niharika; Chand, Pooran; Jurel, Sunit Kumar

2016-01-01

Finger amputations are common in accidents at home, work, and play. Apart from trauma, congenital disease and deformity also leads to finger amputation. This results in loss of function, loss of sensation as well as loss of body image. Finger prosthesis offers psychological support and social acceptance in such cases. This clinical report describes a method to fabricate ring retained silicone finger prosthesis in a patient with partial finger loss.

Dose distribution perturbation due to a Co-Cr-Mo prosthesis

International Nuclear Information System (INIS)

Castro Novais, J.; Rodriguez Rodriguez, C.; Cabello Murillo, E.; Fernandez Leton, P.; Perez Moreno, J. M.; Lopez Fernandez, A.; Ferrando Sanchez, A.; Martinez Gomez, L. C.

2009-01-01

Knowledge of the attenuation and interface effects when irradiating metallic prosthesis is necessary for the radiotherapy treatment of patients with this kind of implants. This report studies the dose distribution of a 6 MV photon beam in the vicinity of a 1,5 cm diameter Co-Cr-Mo prosthesis. Measurements with Gafchromic EBT radiochromic films have been made. Two blocks of cut films have been placed next to the prosthesis, one in each side. Forty two films reaching a height of 1 cm have been piled up in each block. A spatial resolution equal to the thickness of one film (0,24 mm) is achieved. The results show 28% attenuation and the production of a 42% overdose at the entrance interface, 12% and 3% at 1 mm and 2 mm away from the prosthesis respectively. A 5 mm build-up region is originated in the exit interface, where the under dose is less than 10%. The knowledge of the transmission factor and the interface effects allows us to assess the dose calculated by the treatment planning system. (Author) 11 refs.

Referral of sensation to an advanced humanoid robotic hand prosthesis.

Science.gov (United States)

Rosén, Birgitta; Ehrsson, H Henrik; Antfolk, Christian; Cipriani, Christian; Sebelius, Fredrik; Lundborg, Göran

2009-01-01

Hand prostheses that are currently available on the market are used by amputees to only a limited extent, partly because of lack of sensory feedback from the artificial hand. We report a pilot study that showed how amputees can experience a robot-like advanced hand prosthesis as part of their own body. We induced a perceptual illusion by which touch applied to the stump of the arm was experienced from the artificial hand. This illusion was elicited by applying synchronous tactile stimulation to the hidden amputation stump and the robotic hand prosthesis in full view. In five people who had had upper limb amputations this stimulation caused referral touch sensation from the stump to the artificial hand, and the prosthesis was experienced more like a real hand. We also showed that this illusion can work when the amputee controls the movements of the artificial hand by recordings of the arm muscle activity with electromyograms. These observations indicate that the previously described "rubber hand illusion" is also valid for an advanced hand prosthesis, even when it has a robotic-like appearance.

Adhesive strength of hydroxyl apatite(HA coating and biomechanics behavior of HA-coated prosthesis:an experimental study

Directory of Open Access Journals (Sweden)

Tian-yang ZHANG

2011-05-01

Full Text Available Objective To explore the influence of adhesive strength of hydroxyapatite(HA coating on the post-implantation stability of HA-coated prosthesis.Methods The adhesive strength and biomechanics behavior of HA coating were studied by histopathological observation,material parameters and biomechanical testing,the titanium(Ti-coated prosthesis was employed as control.Results Scratch test showed that the adhesive strength of HA coating was significantly lower than that of Ti coating(P < 0.01.Histopathological examination and bone morphometry showed that,at the early stage of prosthesis implantation,the bony growth around HA-coated prosthesis was significantly higher than that around Ti-coated prosthesis(P < 0.01,but the ultimate shear strength of HA-coated prosthesis was much lower than that of Ti-coated prosthesis(P < 0.01.After the push-out test with prosthesis,histopathological observation showed that there were accumulations of clump-and strip-like granular residues on the surface of bones that newly grew around the HA-coated prosthesis,and surface energy-dispersive X-ray spectroscopy(EDX analysis also confirmed that the shear stress induced HA decohesion from the substrate of prosthesis.Conclusions Although HA coating showed a satisfactory effect on early bone formation and prosthetic stability,due to the deficiencies of adhesive strength,the early stability of prosthesis may be gradually destroyed by the shear loads of human body and coating degradation.

Advanced engineering tools for design and fabrication of a custom nasal prosthesis

Science.gov (United States)

Oliveira, Inês; Leal, Nuno; Silva, Pedro; da Costa Ferreira, A.; Neto, Rui J.; Lino, F. Jorge; Reis, Ana

2012-09-01

Unexpected external defects resulting from neoplasms, burns, congenital malformations, trauma or other diseases, particularly when involving partial or total loss of an external organ, can be emotionally devastating. These defects can be restored with prosthesis, obtained by different techniques, materials and methods. The increase of patient numbers and cost constraints lead to the need of exploring new techniques that can increase efficiency. The main goal of this project was to develop a full engineering-based manufacturing process to obtain soft-tissue prosthesis that could provide faster and less expensive options in the manufacturing of customized prosthesis, and at the same time being able to reproduce the highest degree of details, with the maximum comfort for the patient. Design/methodology/approach - This case report describes treatment using silicone prosthesis with an anatomic retention for an 80-years-old woman with a rhinectomy. The proposed methodology integrates non-contact structured light scanning, CT and reverse engineering with CAD/CAM and additive manufacturing technology. Findings - The proposed protocol showed encouraging results since reveals being a better solution for fabricating custom-made facial prostheses for asymmetrical organs than conventional approaches. The process allows the attainment of prosthesis with the minimum contact and discomfort for the patient, disclosing excellent results in terms of aesthetic, prosthesis retention and in terms of time and resources consumed.

The method of manufacture of nylon dental partially removable prosthesis using additive technologies

Science.gov (United States)

Kashapov, R. N.; Korobkina, A. I.; Platonov, E. V.; Saleeva, G. T.

2014-12-01

The article is devoted to the topic of creating new methods of dental prosthesis. The aim of this work is to investigate the possibility of using additive technology to create nylon prosthesis. As a result of experimental studies, was made a sample of nylon partially removable prosthesis using 3D printing has allowed to simplify, accelerate and reduce the coat of manufacturing high-precision nylon dentures.

21 CFR 874.3540 - Prosthesis modification instrument for ossicular replacement surgery.

Science.gov (United States)

2010-04-01

... replacement surgery. 874.3540 Section 874.3540 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... § 874.3540 Prosthesis modification instrument for ossicular replacement surgery. (a) Identification. A prosthesis modification instrument for ossicular replacement surgery is a device intended for use by a...

Predictors of Receiving a Prosthesis for Adults With Above-Knee Amputations in a Well-Defined Population.

Science.gov (United States)

Mundell, Benjamin F; Kremers, Hilal Maradit; Visscher, Sue; Hoppe, Kurtis M; Kaufman, Kenton R

2016-08-01

Prior studies have identified age as a factor in determining an individual's likelihood of receiving a prosthesis following a lower limb amputation. These studies are limited to specific subsets of the general population and are unable to account for preamputation characteristics within their study populations. Our study seeks to determine the effect of preamputation characteristics on the probability of receiving a prosthesis for the general population in the United States. To identify preamputation characteristics that predict of the likelihood of receiving a prosthesis following an above-knee amputation. A retrospective, population-based cohort study. Olmsted County, Minnesota (2010 population: 144,248). Individuals (n = 93) over the age of 18 years who underwent an above-knee amputation, that is, knee disarticulation or transfemoral amputation, while residing in Olmsted County, MN, between 1987 and 2013. Characteristics affecting the receipt of a prosthesis were analyzed using a logistic regression and a random forest algorithm for classification trees. Preamputation characteristics included age, gender, amputation etiology, year of amputation, mobility, cognitive ability, comorbidities, and time between surgery and the prosthesis decision. The association of preamputation characteristics with the receipt of a prosthesis following an above-knee amputation. Twenty-four of the participants received a prosthesis. The odds of receiving a prosthesis were almost 30 times higher in those able to walk independently prior to an amputation relative to those who could not walk independently. A 10-year increase in age was associated with a 53.8% decrease in the likelihood of being fit for a prosthesis (odds ratio = 0.462, P =.030). Time elapsed between surgery and the prosthesis decision was associated with a rise in probability of receiving a prosthesis for the first 3 months in the random forest algorithm. No other observed characteristics were associated with receipt

Strategy to avoid patient-prosthesis mismatch: aortic root enlargement.

Science.gov (United States)

Srivastava, Dharmendra Kumar; Sanki, Prokash; Bhattacharya, Subhankar; Siddique, Javed Veqar

2014-02-01

The choice of a valve with an effective orifice area matching the body surface area and providing efficient hemodynamics is an important factor affecting mortality and morbidity in patients undergoing aortic valve replacement. Our preventative strategy was to implant a larger prosthetic valve by aortic root enlargement using the Nunez procedure in 17 patients between February 2010 and January 2011. The decision to enlarge the aortic root was taken when the 19-mm sizer could not be negotiated easily through the aortic root, or on the basis of body surface area of the patient or type of prosthesis available. Postoperative reductions in peak and mean pressure gradients across aortic valve of 12.8-16.5 and 10.2-12.6 mm Hg, respectively, were observed. Postoperative effective orifice areas of the aortic valves were 1.1-1.5 cm(2). By upsizing the aortic valve, we were able to eliminate patient-prosthesis mismatch in 5 patients, and reduce severe patient-prosthesis mismatch to moderate in 11. Aortic root enlargement is a safe procedure. Therefore, cardiac surgeons should not be reluctant to enlarge the aortic root with an autologous pericardial patch to permit implantation of an adequate size of aortic valve prosthesis, with minimal additional aortic crossclamp time and no added cost.

Smart image processing system for retinal prosthesis.

Science.gov (United States)

Weiland, James D; Parikh, Neha; Pradeep, Vivek; Medioni, Gerard

2012-01-01

Retinal prostheses for the blind have demonstrated the ability to provide the sensation of light in otherwise blind individuals. However, visual task performance in these patients remains poor relative to someone with normal vision. Computer vision algorithms for navigation and object detection were evaluated for their ability to improve task performance. Blind subjects navigating a mobility course had fewer collisions when using a wearable camera system that guided them on a safe path. Subjects using a retinal prosthesis simulator could locate objects more quickly when an object detection algorithm assisted them. Computer vision algorithms can assist retinal prosthesis patients and low-vision patients in general.

[Lessons from a heart valve prosthesis controversy].

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Vandenbroucke, J P; Grobbee, D E

1998-07-18

Two lessons are to be learnt from the Björk-Shiley heart valve prosthesis tragedy. In the first place pharmacoepidemiologic studies are seriously hampered by recent privacy legislation. Individual patients carrying such a prosthesis cannot be traced and advised as to their health risks any more, because their legal autonomy has to be respected. This is clearly not to their advantage. In the second place the atmosphere of marketing and litigation and the increasing dependency of researchers on money from sources with conflicting interests is not conducive to a well-informed and balanced judgement of the epidemiological evidence of safety and efficacy of medical treatments.

Combined nuclear and digital subtraction contrast arthrography in painful knee prosthesis

International Nuclear Information System (INIS)

Namasivayam, J.; Forrester, A.; Poon, F.W.; Cuthbert, G.F.; McKillop, J.H.; Bryan, A.S.

1992-01-01

The evaluation of a painful knee prosthesis remains a difficult problem for both orthopaedic surgeons and radiologists. We have compared digital subtraction arthrography with nuclear-arthrography in 7 patients with a painful knee prosthesis. Three patients showed a loose tibial component, demonstrated by both digital subtraction and nuclear arthrography. All 3 underwent revision of their prosthesis. One patient had an equivocal digital subtraction arthrogram and negative nuclear arthrogram, while both studies were negative in the 3 remaining patients. Nuclear arthrography is a simple procedure and can provide useful additional information when combined with digital subtraction arthrography. (orig.)

21 CFR 878.3720 - Tracheal prosthesis.

Science.gov (United States)

2010-04-01

...) Identification. The tracheal prosthesis is a rigid, flexible, or expandable tubular device made of a silicone... of the trachea or trachealbronchial tree. It may be unbranched or contain one or two branches. The...

Magnetically retained silicone facial prosthesis

African Journals Online (AJOL)

2013-06-09

Jun 9, 2013 ... Prosthetic camouflaging of facial defects and use of silicone maxillofacial material are the alternatives to the surgical retreatment. Silicone elastomers provide more options to clinician for customization of the facial prosthesis which is simple, esthetically good when coupled with bio magnets for retention.

Pattern of External Breast Prosthesis Use by Post Mastectomy Breast Cancer Patients in India: Descriptive Study from Tertiary Care Centre.

Science.gov (United States)

Ramu, D; Ramesh, Rakesh S; Manjunath, Suraj; Shivakumar; Goel, Vipin; Hemnath, G N; Alexander, Annie

2015-12-01

In India, Breast cancer is now the most common cancer in urban and 2nd most common in rural areas [1]. The incidence is rising, more younger women are getting affected and due to increase in survival rates there is an increase in the total number of women suffering from breast Cancer. So far there are no studies evaluating the pattern of breast prosthesis use in Indian scenario. The aim of this study is to address the patterns of external breast prosthesis used in India and view of Indian women on such prosthesis after mastectomy for breast cancer. This was a descriptive longitudinal study. In this study we interviewed (telephonic) 63 people, after three years of completing treatment under The Department of Surgical Oncology, St. Johns medical college, Bangalore. Among the study group, 27 members (40 %) were using various prosthesis, rest 36 women were not using any type of prosthesis. Among the users of prosthesis, silicon prosthesis was used by 6 women, padded cups by 8 women, cloth or cotton by 12 women and 1 woman used other type of prosthesis. Most women use simple items like cloth and cotton (44 %). Next most commonly used prosthesis are padded cups(). Only 22 % of women were found using silicon prosthesis in this study. Most of the well educated patients used external prosthesis either in the form of silicon prosthesis or padded cups. Most of women below age of 50 used external breast prosthesis. Use of prosthesis was more in urban compared to rural population (48 % vs 25 %). Prosthesis users worried more about the body image than women not using prosthesis. 25 % of women using prosthesis had body image issues where as only 5 % of non prosthesis users had such problems. Prosthesis users need improvement in terms of comfort, size, shape and affordability. Most common reasons for not using prosthesis are age, lack of motivation and awareness. Less than half of the women included in this study used external prosthesis after mastectomy for breast cancer

Candida albicans, Staphylococcus aureus and Streptococcus mutans colonization in patients wearing dental prosthesis.

Science.gov (United States)

Baena-Monroy, Tania; Moreno-Maldonado, Víctor; Franco-Martínez, Fernando; Aldape-Barrios, Beatriz; Quindós, Guillermo; Sánchez-Vargas, Luis Octavio

2005-04-01

Denture stomatitis is associated to Candida albicans, different bacteria and other co-factors such as an acid pH, a carbohydrate ingestion increase, different systemic illnesses and pharmacological treatments. The aim of this study was to determine Candida albicans, Staphylococcus aureus and Streptococcus mutans prevalence in the mucous membrane and prosthesis of patients with and without atrophic denture stomatitis and its relationship with other potential clinical co-factors. Saliva was collected from 105 patients (62 female and 43 male) wearing dental prosthesis in order to measure their pH. Oral samples of the mucous membrane and the internal surface of dental prosthesis were taken with sterile cotton to proceed with the microbiological study. The identification of the isolated microorganisms was performed using conventional microbiological methods. Diabetes and Hypertension were the most frequent systemic illnesses. High carbohydrate ingestion was observed in numerous patients. Atrophic denture stomatitis was reported in 50 patients and the pH average in saliva was of 5.2. The presence of C albicans, S. aureus and S. mutans in the mucous membrane and prosthesis was of 51.4%, 52.4% and 67.6%, respectively. C. albicans was isolated in 66.7% from the prosthesis, whereas S. aureus and S. mutans were isolated in 49.5% of those same prosthesis. C. albicans was isolated in 86% of the patients with atrophic denture stomatitis and S. aureus was isolated in a similar percentage (84% of patients). The isolation of S. mutans was less frequent, and it was observed in 16% of the oral samples of these patients. C. albicans, S. aureus and S. mutans frequently colonize the oral mucous of patients wearing dental prosthesis. This illness-bearing condition is more frequent in patients with denture stomatitis, even though dental prosthesis colonization is lower than in the oral mucous.

Survival of various implant-supported prosthesis designs following 36 months of clinical function.

Science.gov (United States)

Rodriguez, A M; Orenstein, I H; Morris, H F; Ochi, S

2000-12-01

The use of endosseous dental implants to replace natural teeth lost to trauma, dental caries, or periodontal disease has become a predictable form of prosthetic treatment since gaining popularity in the early 1980s. While numerous clinical studies have focused on the survival of implants, few address the survival of different prosthesis designs. Beginning in 1991, 882 prostheses supported by more than 2,900 implants (687 patients) were placed by the Department of Veterans Affairs Dental Implant Clinical Research Group (DICRG). These prostheses were divided into five research strata based on arch location. The recommended design for each stratum was: bar-supported overdenture (maxillary completely edentulous); screw-retained hybrid denture (mandibular completely edentulous); screw-retained fixed partial denture (mandibular and maxillary posterior partially edentulous); and cemented single crown (maxillary anterior single tooth). Alternative overdenture designs were utilized in the edentulous arches when the recommended prosthesis could not be fabricated. Prosthesis success rates for the research strata were calculated for an observation time of up to 36 months following prosthesis placement. Success rates for the maxillary edentulous stratum ranged from 94.6% for the bar-retained overdenture supported by five to six fixtures to 81.8% for the cap-retained overdenture. The mandibular edentulous strata produced success rates of 98.1% for the fixed hybrid prosthesis to 91.7% for the cap-retained prosthesis. Success rates for maxillary and mandibular posterior fixed partial dentures were 94.3% and 92.6%, respectively, while the maxillary anterior single-tooth prosthesis yielded a success rate of 98.1% for the 36-month observation period. The recommended prosthesis designs investigated in this study proved to be reliable, with encouraging success rates for an observation period of 36 months following placement.

Retrospective Study on External Canine Limb Prosthesis used in 24 patients

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Brittany Jean Carr

2018-03-01

Full Text Available Objective: The purpose of this retrospective study is to provide data regarding external prosthetic use in small animal patients, evaluate the common complications associated with external prosthetics, and evaluate the outcome of patients using an external prosthetic.Background: The use of external canine limb prosthetics is relatively uncommon in veterinary medicine today.  However, there is growing interest in prosthetics and their clinical application because these devices may offer an alternative to euthanasia in severe cases where full amputation or alternative methods of limb spare are not an option. The goal of the prosthesis is to provide a better quality of life, help prevent further deformation and degeneration of existing joints, decrease leg length discrepancies, increase exercise and activity levels, provide a means to participate in rehabilitation therapy and maintain the ability to perform daily acts of living. To the author’s knowledge, there is no report of external prosthetic use in small animal veterinary medicine, providing the profession with baseline information for use in, not only general practice or referral practice, but also future research.Evidentiary value: This retrospective study provides data regarding external prosthetic use in small animal patients, evaluates the procedures, manufacturing, rehabilitation and common complications associated with external prosthetics, and evaluates the factors that determine a patient’s prosthetic candidacy.Methods: Patients that had an external prosthesis custom manufactured for them at Animal Orthocare, LLC and had a complete medical record were identified for this study.  A client survey was completed via e-mail or telephone to collect further data about the patients, including age, weight, breed, sex, affected limb(s, reason for prosthesis, level of amputation, activities patient could perform with prosthesis in place, prosthetic fit, prosthetic migration (e

Research, design and development project Myoelectric Prosthesis of Upper Limb

International Nuclear Information System (INIS)

Galiano, L; Montaner, E; Flecha, A

2007-01-01

A Research Design and Development Project was developed of a myoelectric prosthesis for a pediatric patient presenting congenital amputation of the left forearm below the elbow. A multidisciplinary work-team was formed for this goal, in order to solve the several (/various) aspects regarding this project (mechanical, ergonomics, electronics, physical). The prosthesis as an electromechanical device was divided in several blocks, trying to achieve a focused development for each stage, acording to requisites. A mechanical prototype of the prothesis was designed and built along with the circuitry needed for EMG aquisition, control logic and drivers. Having acomplished the previuos stages, the project is now dealing with the definitions of the interface between the prosthesis and the patient, with promising perspectives

Research, design and development project Myoelectric Prosthesis of Upper Limb

Energy Technology Data Exchange (ETDEWEB)

Galiano, L; Montaner, E; Flecha, A [Bioparx, J Hernandez 1101, Parana, ERios (Argentina)

2007-11-15

A Research Design and Development Project was developed of a myoelectric prosthesis for a pediatric patient presenting congenital amputation of the left forearm below the elbow. A multidisciplinary work-team was formed for this goal, in order to solve the several (/various) aspects regarding this project (mechanical, ergonomics, electronics, physical). The prosthesis as an electromechanical device was divided in several blocks, trying to achieve a focused development for each stage, acording to requisites. A mechanical prototype of the prothesis was designed and built along with the circuitry needed for EMG aquisition, control logic and drivers. Having acomplished the previuos stages, the project is now dealing with the definitions of the interface between the prosthesis and the patient, with promising perspectives.

Prosthesis-patient mismatch due to small ring annuloplasty in patients with degenerative mitral insufficiency.

Science.gov (United States)

Kawamoto, Naonori; Fujita, Tomoyuki; Hata, Hiroki; Shimahara, Yusuke; Sato, Shunsuke; Kobayashi, Junjiro

2016-08-01

Avoidance of prosthesis-patient mismatch (PPM) is important when selecting a mitral valve prosthesis. This study investigated the effect of PPM after small ring mitral valve annuloplasty on postoperative hemodynamics and the clinical course. This study retrospectively reviewed 227 patients with symptomatic severe mitral insufficiency (MI) who underwent mitral valve repair for degenerative MI using an Edwards ring or band (size: 26-32mm) between 2003 and 2012. Echocardiography was performed postoperatively and at follow-up to evaluate cardiac function, including residual MI, mean transmitral pressure gradient, left atrial diameter (LAD), and tricuspid regurgitant pressure gradient (TRPG). There were no operative deaths. Actuarial freedom from major adverse cardiac events was 91% at 10 years. The postoperative MI grade was not significantly different between different sizes of prosthesis (26mm, 0.67±0.8; 28mm, 0.73±0.9; 30mm, 0.85±0.9; 32mm, 0.3±0.6). LAD and TRPG were significantly lower for each size of prosthesis at follow-up (all pbody surface area received a significantly smaller prosthesis (pprosthesis than in patients with a larger size of prosthesis. Thirty-three patients had a follow-up transmitral pressure gradient ≥5mmHg. The follow-up LAD was larger in patients with a transmitral pressure gradient prosthesis. However, use of a smaller prosthesis may result in a higher mean transmitral pressure gradient, and may inhibit reverse remodeling of the left atrium. Therefore, PPM should be avoided. Copyright © 2015 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

A distinct subtype of ''metatropic dysplasia variant'' characterised by advanced carpal skeletal age and subluxation of the radial heads

International Nuclear Information System (INIS)

Nishimura, G.; Satoh, Masato; Aihara, Toshinori; Aida, Noriko; Yamamoto, Takehisa; Ozono, Keiichi

1998-01-01

Background. ''Metatropic dysplasia variants'' are a group of bone dysplasias whose skeletal abnormalities are similar to, but milder than, those of classical metatropic dysplasia. The genetic and phenotypic heterogeneity has not been thoroughly elucidated. Objective. The objective was to designate a distinct subtype of these metatropic dysplasia variants. Materials and methods. The subjects were four Japanese patients, two sporadic cases and two siblings, who all had identical skeletal changes. The radiological features in these patients were compared with those of previously reported metatropic dysplasia variants. Results. Moderate platyspondyly with pear-shaped and/or anterior-tongued vertebral bodies, halberd pelvis, and dumbbell deformity of the tubular bones were regarded as hallmarks of metatropic dysplasia variants. The peculiar skeletal change in our patients was advanced carpal skeletal age in childhood, unlike most patients reported as metatropic dysplasia variants who manifest delayed carpal ossification. Another hallmark was congenital dislocation of the radial heads. A description of a patient with similar skeletal changes was found in the literature. Conclusion. These patients are considered to represent a distinct subgroup of metatropic dysplasia variants. It remains unknown whether the present siblings represent an autosomal recessive trait or an autosomal dominant trait with germinal mosaicism related to increased paternal age. (orig.)

Evaluation of possible hip prosthesis infection with In-111 leukocyte scintigraphy

International Nuclear Information System (INIS)

Noto, R.B.; Alavi, A.; Star, A.M.; Cuckler, J.M.; Eisenberg, B.

1987-01-01

To evaluate the utility of In-111 leukocyte scintigraphy in patients with possible hip prosthesis infection, the authors retrospectively reviewed 44 such scans without clinical history. The results of In-111 leukocyte scans were compared with intraoperative cultures obtained at the time of prosthesis revision in 34 patients, with hip aspirates and/or clinical follow-up obtained in the remaining ten patients. This comparison yielded a 71% sensitivity, 78% specificity, and 77% overall accuracy. They conclude that In-111 leukocyte scans can be helpful in the evaluation of suspected hip prosthesis infection, but they are not as accurate as has been previously reported elsewhere

A Structural Analysis of a Mechanical Heart Valve Prosthesis with Flat Leaflet

Science.gov (United States)

Kwon, Young Joo

This paper addresses the basic concept of MDO methodology and the structural analysis that should be performed in the design process of a mechanical heart valve prosthesis with flat leaflet using MDO methodology. In the structural design of the mechanical heart valve (MHV) prosthesis, the fluid mechanics analysis is executed for the blood flow passing through the leaflets of a mechanical heart valve prosthesis. Thereafter, the rigid body dynamics analysis of the leaflet motion is performed to obtain the structural condition for the structural mechanics analysis of the deformed leaflet. Then the structural mechanics analysis of the deformed leaflet follows to confirm the minimum thickness of the leaflet for the structural durability of the mechanical heart valve prosthesis. This paper shows that the minimum leaflet thickness can be evaluated to be 0.6mm among the suggested thicknesses.

Effect of silicone gel breast prosthesis on electron and photon dose distributions

International Nuclear Information System (INIS)

Krishnan, L.; St George, F.J.; Mansfield, C.M.; Krishnan, E.C.

1983-01-01

The effect of a silicone gel breast prosthesis on the absorbed dose distribution of 9--20 MeV electron beams and 1.25--15 MV photon beams was studied. Compared to water measurements, at depths smaller than the practical range of the electron beams, the central axis depth dose values below the prothesis were lower for all energies by as much as 3.5%. However, at depths near the practical range, the central axis depth dose values for the prosthesis were greater than that of water by as much as 33%. Since this occurs near the end of the electron range, the resultant difference may not be clinically significant. Results of the effect of breast prosthesis on photon depth dose distributions reveal that no clinically significant perturbation is produced by the breast prosthesis using Co-60, 6- and 15-MV radiations

Energy Performance and Radial Force of a Mixed-Flow Pump with Symmetrical and Unsymmetrical Tip Clearances

Directory of Open Access Journals (Sweden)

Yue Hao

2017-01-01

Full Text Available The energy performance and radial force of a mixed flow pump with symmetrical and unsymmetrical tip clearance are investigated in this paper. As the tip clearance increases, the pump head and efficiency both decrease. The center of the radial force on the principal axis is located at the coordinate origin when the tip clearance is symmetrical, and moves to the third quadrant when the tip clearance is unsymmetrical. Analysis results show that the total radial force on the principal axis is closely related to the fluctuation of mass flow rate in each single flow channel. Unsteady simulations show that the dominant frequencies of radial force on the hub and blade correspond to the blade number, vane number, or double blade number because of the rotor stator interaction. The radial force on the blade pressure side decreases with the tip clearance increase because of leakage flow. The unsymmetrical tip clearances in an impeller induce uneven leakage flow rate and then result in unsymmetrical work ability of each blade and flow pattern in each channel. Thus, the energy performance decreases and the total radial force increases for a mixed flow pump with unsymmetrical tip clearance.

Radial nerve dysfunction

Science.gov (United States)

Neuropathy - radial nerve; Radial nerve palsy; Mononeuropathy ... Damage to one nerve group, such as the radial nerve, is called mononeuropathy . Mononeuropathy means there is damage to a single nerve. Both ...

Quantifying risk of penile prosthesis infection with elevated glycosylated hemoglobin.

Science.gov (United States)

Wilson, S K; Carson, C C; Cleves, M A; Delk, J R

1998-05-01

Elevation of glycosylated hemoglobin above levels of 11.5 mg.% has been considered a contraindication to penile prosthesis implantation in diabetic patients. We determine the predictive value of glycosylated hemoglobin A1C in penile prosthesis infections in diabetic and nondiabetic patients to confirm or deny this prevalent opinion. We conducted a 2-year prospective study of 389 patients, including 114 diabetics, who underwent 3-piece penile prosthesis implantation. All patients had similar preoperative preparation without regard to diabetic status, control or glycosylated hemoglobin A1C level. Risk of infection was statistically analyzed for diabetics versus nondiabetics, glycosylated hemoglobin A1C values above and below 11.5 mg.%, insulin dependent versus oral medication diabetics, and fasting blood sugars above and below 180 mg.%. Prosthesis infections developed in 10 diabetics (8.7%) and 11 nondiabetics (4.0%). No increased infection rate was observed in diabetics with high fasting sugars or diabetics on insulin. There was no statistically significant increased infection risk with increased levels of glycosylated hemoglobin A1C among all patients or among only the diabetics. In fact, there was no meaningful difference in the median or mean level of glycosylated hemoglobin A1C in the infected and noninfected patients regardless of diabetes. Use of glycosylated hemoglobin A1C values to identify and exclude surgical candidates with increased risk of infections is not proved by this study. Elevation of fasting sugar or insulin dependence also does not increase risk of infection in diabetics undergoing prosthesis implantation.

Wispy Prosthesis: A Novel Method in Denture Weight Reduction.

Science.gov (United States)

Anne, Gopinadh; Budeti, Sreedevi; Anche, Sampath Kumar; Zakkula, Srujana; Atla, Jyothi; Jyothula, Ravi Rakesh Dev; Appana, Krishna Chaitanya; Peddinti, Vijaya Kumar

2016-04-01

Stability and retention of the denture becomes at stake with the increase in weight of the denture prosthesis. As a consequence, different materials and methods have been introduced to overcome these issues but denture weight reduction still remains to be a cumbersome and strenuous procedure. To introduce a novel technique for the fabrication of denture prosthesis where in the weight of the denture will not affect the retention and stability of the denture. Four groups with a sample size of 10 each, were included where in one group was control and other three were study groups. The control group samples were made completely solid and the study group samples were packed with materials like bean balls, cellulose balls and polyacrylic fibers. The weight of all the samples of each study group was measured and compared with the control group. The observations were analyzed statistically by paired t-test. It was observed that the bean balls group produced a weight reduction of 31.3%, cellulose balls group 27.4% and polyacrylic fibers group 24.5% when compared to that of the control group. This novel technique will eliminate the problems that were associated in creating hollowness and at the same time will reduce the weight of the prosthesis and among all the study groups, bean balls group were found to reduce maximum weight of the prosthesis.

A fiber-reinforced composite prosthesis restoring a lateral midfacial defect: a clinical report.

Science.gov (United States)

Kurunmäki, Hemmo; Kantola, Rosita; Hatamleh, Muhanad M; Watts, David C; Vallittu, Pekka K

2008-11-01

This clinical report describes the use of a glass fiber-reinforced composite (FRC) substructure to reinforce the silicone elastomer of a large facial prosthesis. The FRC substructure was shaped into a framework and embedded into the silicone elastomer to form a reinforced facial prosthesis. The prosthesis is designed to overcome the disadvantages associated with traditionally fabricated prostheses; namely, delamination of the silicone of the acrylic base, poor marginal adaptation over time, and poor simulation of facial expressions.

Subway Mandibular Buccal Defect Blocked with Two Part Prosthesis Unified by Earth Magnets

OpenAIRE

Punjani, Shikha; Arora, Aman; Upadhyaya, Viram

2012-01-01

This clinical report describes the fabrication of a two-piece obturator used to close the mandibular buccal defect. Two-piece obturator prosthesis was fabricated with clear heat cure acrylic resin to be used during the healing period following the marsupialization of odontogenic keratocyst which had lead to the loss of portions of the mandibular buccal region. The prosthesis fabricated in two parts was joined by the rare earth magnets. Retention was increased by lining the prosthesis with tis...

Aspiration of tracheoesophageal prosthesis in a laryngectomized patient

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Conte Sergio C

2012-08-01

Full Text Available Abstract Background The voice prosthesis inserted into a tracheoesophageal fistula has become the most widely used device for voice rehabilitation in patients with total laryngectomy. Case presentation We describe a case of tracheoesophageal prosthesis’ (TEP aspiration in a laryngectomized patient, with permanent tracheal stoma, that appeared during standard cleaning procedure, despite a programme of training for the safe management of patients with voice prosthesis. Conclusions The definitive diagnosis and treatment were performed by flexible bronchoscopy, that may be considered the procedure of choice in these cases, also on the basis of the literature.

Tracheobronchial Foreign Body Aspiration: Dental Prosthesis

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Ataman Köse

2014-01-01

Full Text Available It is important to extract foreign bodies for avoiding life-threatening complications. They can lead to death if they are not treated. Different signs and symptoms could occur according to the complete or partial airway obstruction. Foreign body aspiration is a rare incident in adults. The organic foreign materials such as foods are found to be aspirated more commonly and are usually settled in the right bronchial system. However, dental prosthesis and teeth aspirations are rare in literature. In our study, a 52-year-old male patient who had aspirated the front part of his lower dental prosthesis accidentally is presented and the foreign body is extracted by using rigid bronchoscopy. There are many causes of aspiration but dental prosthetic aspirations should be kept in mind during sleep. For this reason, dental apparatus must be taken out while asleep.

Directional plasticity rapidly improves 3D vestibulo-ocular reflex alignment in monkeys using a multichannel vestibular prosthesis.

Science.gov (United States)

Dai, Chenkai; Fridman, Gene Y; Chiang, Bryce; Rahman, Mehdi A; Ahn, Joong Ho; Davidovics, Natan S; Della Santina, Charles C

2013-12-01

Bilateral loss of vestibular sensation can be disabling. We have shown that a multichannel vestibular prosthesis (MVP) can partly restore vestibular sensation as evidenced by improvements in the 3-dimensional angular vestibulo-ocular reflex (3D VOR). However, a key challenge is to minimize misalignment between the axes of eye and head rotation, which is apparently caused by current spread beyond each electrode's targeted nerve branch. We recently reported that rodents wearing a MVP markedly improve 3D VOR alignment during the first week after MVP activation, probably through the same central nervous system adaptive mechanisms that mediate cross-axis adaptation over time in normal individuals wearing prisms that cause visual scene movement about an axis different than the axis of head rotation. We hypothesized that rhesus monkeys would exhibit similar improvements with continuous prosthetic stimulation over time. We created bilateral vestibular deficiency in four rhesus monkeys via intratympanic injection of gentamicin. A MVP was mounted to the cranium, and eye movements in response to whole-body passive rotation in darkness were measured repeatedly over 1 week of continuous head motion-modulated prosthetic electrical stimulation. 3D VOR responses to whole-body rotations about each semicircular canal axis were measured on days 1, 3, and 7 of chronic stimulation. Horizontal VOR gain during 1 Hz, 50 °/s peak whole-body rotations before the prosthesis was turned on was prosthetic stimulation under normal diurnal lighting. Similar improvements were noted for all animals, all three axes of rotation tested, for all sinusoidal frequencies tested (0.05-5 Hz), and for high-acceleration transient rotations. VOR asymmetry changes did not reach statistical significance, although they did trend toward slight improvement over time. Prior studies had already shown that directional plasticity reduces misalignment when a subject with normal labyrinths views abnormal visual scene

[Spatiotemporal variation of Populus euphratica's radial increment at lower reaches of Tarim River after ecological water transfer].

Science.gov (United States)

An, Hong-Yan; Xu, Hai-Liang; Ye, Mao; Yu, Pu-Ji; Gong, Jun-Jun

2011-01-01

Taking the Populus euphratica at lower reaches of Tarim River as test object, and by the methods of tree dendrohydrology, this paper studied the spatiotemporal variation of P. euphratic' s branch radial increment after ecological water transfer. There was a significant difference in the mean radial increment before and after ecological water transfer. The radial increment after the eco-water transfer was increased by 125%, compared with that before the water transfer. During the period of ecological water transfer, the radial increment was increased with increasing water transfer quantity, and there was a positive correlation between the annual radial increment and the total water transfer quantity (R2 = 0.394), suggesting that the radial increment of P. euphratica could be taken as the performance indicator of ecological water transfer. After the ecological water transfer, the radial increment changed greatly with the distance to the River, i.e. , decreased significantly along with the increasing distance to the River (P = 0.007). The P. euphratic' s branch radial increment also differed with stream segment (P = 0.017 ), i.e. , the closer to the head-water point (Daxihaizi Reservoir), the greater the branch radial increment. It was considered that the limited effect of the current ecological water transfer could scarcely change the continually deteriorating situation of the lower reaches of Tarim River.

Radial nerve injury following elbow external fixator: report of three cases and literature review.

Science.gov (United States)

Trigo, Luis; Sarasquete, Juan; Noguera, Laura; Proubasta, Ignacio; Lamas, Claudia

2017-07-01

Radial nerve palsy is a rare but serious complication following elbow external fixation. Only 11 cases have been reported in the literature to date, but the incidence may be underreported. We present three new cases of this complication. We analyzed the three cases of radial palsy seen in our center following the application of an external fixator as treatment for complex elbow injuries. Mean patient age at surgery was 50 years. Two patients were female and one was male. In the three cases, the initial lesion was a posterior elbow dislocation, associated with a fracture of the radial shaft in one and a radial head fracture and coronoid fracture, respectively, in the other two. Due to persistent elbow instability, an external fixator was applied in all three cases. The fixator pins were introduced percutaneously in two cases and under direct vision in an open manner in the third case. Radial palsy was noted immediately postoperatively in all cases. It was permanent in two cases and temporary in the third. Radial nerve palsy after placement of an external elbow fixator was resolved in only 1 of our 3 cases and in 6 of the 11 cases in the literature to date. Although the event is rare, these alarming results highlight the need for recommendations to avoid this complication.

Stress analysis of different prosthesis materials in implant-supported fixed dental prosthesis using 3D finite element method

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Pedram Iranmanesh

2014-01-01

Full Text Available Introduction: In the present study, the finite element method (FEM was used to investigate the effects of prosthesis material types on stress distribution of the bone surrounding implants and to evaluate stress distribution in three-unit implant-supported fixed dental prosthesis (FDP. Materials and Methods: A three-dimensional (3D finite element FDP model of the maxillary second premolar to the second molar was designed. Three load conditions were statically applied on the functional cusps in horizontal (57.0 N, vertical (200.0 N, and oblique (400.0 N, θ = 120° directions. Four standard framework materials were evaluated: Polymethyl methacrylate (PMMA, base-metal, porcelain fused to metal, andporcelain. Results: The maximum of von Mises stress in the oblique direction was higher than the vertical and horizontal directions in all conditions. In the bone-crestal section, the maximum von Mises stress (53.78 MPa was observed in PMMA within oblique load. In FDPs, the maximum stress was generated at the connector region in all conditions. Conclusion: A noticeable difference was not observed in the bone stress distribution pattern with different prosthetic materials. Although, higher stress value could be seen in polymethyl methacrylate, all types of prosthesis yielded the same stress distribution pattern in FDP. More clinical studies are needed to evaluate the survival rate of these materials.

Adjuvant Maneuvers for Residual Curvature Correction During Penile Prosthesis Implantation in Men with Peyronie's Disease.

Science.gov (United States)

Berookhim, Boback M; Karpman, Edward; Carrion, Rafael

2015-11-01

The surgical treatment of comorbid erectile dysfunction and Peyronie's disease has long included the implantation of an inflatable penile prosthesis as well as a number of adjuvant maneuvers to address residual curvature after prosthesis placement. To review the various surgical options for addressing curvature after prosthesis placement, with specific attention paid to an original article by Wilson et al. reporting on modeling over a penile prosthesis for the management of Peyronie's disease. A literature review was performed analyzing articles reporting the management of penile curvature in patients undergoing implantation of an inflatable penile prosthesis. Reported improvement in Peyronie's deformity as well as the complication rate associated with the various surgical techniques described. Modeling is a well-established treatment modality among patients with Peyronie's disease undergoing penile prosthesis implantation. A variety of other adjuvant maneuvers to address residual curvature when modeling alone is insufficient has been presented in the literature. Over 20 years of experience with modeling over a penile prosthesis have proven the efficacy and safety of this treatment option, providing the surgeon a simple initial step for the management of residual curvature after penile implantation which allows for the use of additional adjuvant maneuvers in those with significant deformities. © 2015 International Society for Sexual Medicine.

Insidious strut fractures in a DeBakey-Surgitool aortic valve prosthesis.

Science.gov (United States)

Scott, S M; Sethi, G K; Paulson, D M; Takaro, T

1978-04-01

Recent reports of cage wear occurring in DeBakey-Surgitool aortic valve prostheses prompted us to examine with image intensification all our patients who have had this type of prosthesis implanted. One patient, who was asymptomatic, was discovered to have a prosthesis with two fractured struts. This patient's prosthetic valve was replaced successfully with a stented porcine heterograft prosthesis. Including the valve removed from this patient, 8 DeBakey-Surgitool aortic valves with structural defects have been reported to the manufacturer. In the absence of a catastrophic event, patients with valves having fractured or worn struts may be totally asymptomatic, and routine periodic roentgenographic examination may be the only way of detecting strut wear or fracture.

A unified model of heading and path perception in primate MSTd.

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Oliver W Layton

2014-02-01

Full Text Available Self-motion, steering, and obstacle avoidance during navigation in the real world require humans to travel along curved paths. Many perceptual models have been proposed that focus on heading, which specifies the direction of travel along straight paths, but not on path curvature, which humans accurately perceive and is critical to everyday locomotion. In primates, including humans, dorsal medial superior temporal area (MSTd has been implicated in heading perception. However, the majority of MSTd neurons respond optimally to spiral patterns, rather than to the radial expansion patterns associated with heading. No existing theory of curved path perception explains the neural mechanisms by which humans accurately assess path and no functional role for spiral-tuned cells has yet been proposed. Here we present a computational model that demonstrates how the continuum of observed cells (radial to circular in MSTd can simultaneously code curvature and heading across the neural population. Curvature is encoded through the spirality of the most active cell, and heading is encoded through the visuotopic location of the center of the most active cell's receptive field. Model curvature and heading errors fit those made by humans. Our model challenges the view that the function of MSTd is heading estimation, based on our analysis we claim that it is primarily concerned with trajectory estimation and the simultaneous representation of both curvature and heading. In our model, temporal dynamics afford time-history in the neural representation of optic flow, which may modulate its structure. This has far-reaching implications for the interpretation of studies that assume that optic flow is, and should be, represented as an instantaneous vector field. Our results suggest that spiral motion patterns that emerge in spatio-temporal optic flow are essential for guiding self-motion along complex trajectories, and that cells in MSTd are specifically tuned to extract

A Unified Model of Heading and Path Perception in Primate MSTd

Science.gov (United States)

Layton, Oliver W.; Browning, N. Andrew

2014-01-01

Self-motion, steering, and obstacle avoidance during navigation in the real world require humans to travel along curved paths. Many perceptual models have been proposed that focus on heading, which specifies the direction of travel along straight paths, but not on path curvature, which humans accurately perceive and is critical to everyday locomotion. In primates, including humans, dorsal medial superior temporal area (MSTd) has been implicated in heading perception. However, the majority of MSTd neurons respond optimally to spiral patterns, rather than to the radial expansion patterns associated with heading. No existing theory of curved path perception explains the neural mechanisms by which humans accurately assess path and no functional role for spiral-tuned cells has yet been proposed. Here we present a computational model that demonstrates how the continuum of observed cells (radial to circular) in MSTd can simultaneously code curvature and heading across the neural population. Curvature is encoded through the spirality of the most active cell, and heading is encoded through the visuotopic location of the center of the most active cell's receptive field. Model curvature and heading errors fit those made by humans. Our model challenges the view that the function of MSTd is heading estimation, based on our analysis we claim that it is primarily concerned with trajectory estimation and the simultaneous representation of both curvature and heading. In our model, temporal dynamics afford time-history in the neural representation of optic flow, which may modulate its structure. This has far-reaching implications for the interpretation of studies that assume that optic flow is, and should be, represented as an instantaneous vector field. Our results suggest that spiral motion patterns that emerge in spatio-temporal optic flow are essential for guiding self-motion along complex trajectories, and that cells in MSTd are specifically tuned to extract complex trajectory

A Biomechanical Model for the Development of Myoelectric Hand Prosthesis Control Systems

NARCIS (Netherlands)

Peerdeman, B.; van Baal, D.W.; Boere, Daphne; Kallenberg, L.A.C.; Stramigioli, Stefano; Misra, Sarthak

2010-01-01

Advanced myoelectric hand prostheses aim to reproduce as much of the human hand's functionality as possible. Development of the control system of such a prosthesis is strongly connected to its mechanical design; the control system requires accurate information on the prosthesis' structure and the

Utilization of penile prosthesis and male incontinence prosthetics in Saudi Arabia

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Amjad Alwaal

2017-01-01

Conclusions: There is an increased utilization of penile prosthetics in Saudi Arabia. The private sector performs the majority of penile prosthesis procedures, and most of them are of the semirigid type. The governmental sector is more likely to perform inflatable penile prosthesis and male incontinence device procedures. Male incontinence prosthetics' use is very limited in Saudi Arabia.

Versatility of radial forearm free flap for intraoral reconstruction

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Jeremić Jelena V.

2015-01-01

Full Text Available Introduction. The radial forearm free flap has an important role in reconstruction of the oncologic defects in the region of head and neck. Objective. The aim was to present and evaluate clinical experience and results in the radial forearm free transfer for intraoral reconstructions after resections due to malignancies. Methods. This article illustrates the versatility and reliability of forearm single donor site in 21 patients with a variety of intraoral oncologic defects who underwent immediate (19 patients, 90.5% or delayed (2 patients, 9.5% reconstruction using free flaps from the radial forearm. Fascio-cutaneous flaps were used in patients with floor of the mouth (6 cases, buccal mucosa (5 cases, lip (1 case and a retromolar triangle (2 cases defects, or after hemiglossectomy (7 cases. In addition, the palmaris longus tendon was included with the flap in 2 patients that required oral sphincter reconstruction. Results. An overall success rate was 90.5%. Flap failures were detected in two (9.5% patients, in one patient due to late ischemic necrosis, which appeared one week after the surgery, and in another patient due to venous congestion, which could not be salvaged after immediate re-exploration. Two patients required re-exploration due to vein thrombosis. The donor site healed uneventfully in all patients, except one, who had partial loss of skin graft. Conclusion. The radial forearm free flap is, due to multiple advantages, an acceptable method for reconstructions after resection of intraoral malignancies. [Projekat Ministarstva nauke Republike Srbije, br. 41006

An “Uncrimped” SMart Stapes Prosthesis: A Cause of Late Hearing Deterioration in Otosclerosis

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Premjit S. Randhawa

2012-01-01

Full Text Available Statement of Problem. Stapedotomy is the treatment of choice for otosclerosis. Numerous techniques and prosthesis are available to perform this procedure. Success rates of surgery vary from 17% to 80%, and revision surgery carries an increased risk of complications as well as poorer hearing outcomes. Method of Study. Case report. Results. We report the first case of uncrimping of a SMart stapes prosthesis with no lateral displacement as a cause of late failure despite successful crimping and improvement in audiological outcomes after initial surgery. Conclusion. The SMart stapes prosthesis is widely used and has been shown to be safe and provide good hearing outcomes. Displacement of a stapes prosthesis is the commonest cause of failure. Our case shows that deterioration of hearing thresholds can occur from uncrimping of the prosthesis with no displacement. It is important to improve our understanding of stapedotomy failure as revision procedures are associated with poorer outcomes.

Prosthesis Prescription Protocol of the Arm (PPP-Arm) : The implementation of a national prosthesis prescription protocol

NARCIS (Netherlands)

Wijdenes, Paula; Brouwers, Michael; van der Sluis, Corry K

BACKGROUND AND AIM: In order to create more uniformity in the prescription of upper limb prostheses by Dutch rehabilitation teams, the development and implementation of a Prosthesis Prescription Protocol of the upper limb (PPP-Arm) was initiated. The aim was to create a national digital protocol to

PARTIAL REPLACEMENT OF THE ESOPHAGEAL MUSCLE LAYERS BY A CARBON-FIBER PROSTHESIS

NARCIS (Netherlands)

RUKA, MP; TUNGEKAR, MF; KUIT, J; HOFSTRA, W

1991-01-01

In the present study we report on the surgical replacement of the thoracic portion of oesophageal muscularis by a synthetic carbon fibre (CF) prosthesis in a rabbit model. Our results, as corroborated by the oesophagograms and the post-operative weight gain, showed that this prosthesis functioned

Perforator anatomy of the radial forearm free flap versus the ulnar forearm free flap for head and neck reconstruction

NARCIS (Netherlands)

Hekner, D.D.; Roeling, TAP; van Cann, EM

The aim of this study was to investigate the vascular anatomy of the distal forearm in order to optimize the choice between the radial forearm free flap and the ulnar forearm free flap and to select the best site to harvest the flap. The radial and ulnar arteries of seven fresh cadavers were

Restoration of an atrophic eye socket with custom made eye prosthesis, utilizing digital photography

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Gaurav P Jayaswal

2011-01-01

Full Text Available Ocular defects may cause several ocular and orbital disorders, which require surgical intervention. These defects are psychologically disturbing for the patients, and therefore, they require immediate management and rehabilitation by a team of specialist. Ocular prosthesis may be either readymade (stock or custom made. Fabrication of a custom ocular prosthesis allows for a range of variations during construction. The iris can also be custom made by ocular painting or by digital photography. The optimum cosmetic and functional results of a custom-made prosthesis enhance the patient′s rehabilitation to a normal life style. This paper elaborates the technique for fabrication of a custom-made ocular prosthesis for an atrophic eye socket utilizing digital photography.

Optimization of Visual Information Presentation for Visual Prosthesis

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Fei Guo

2018-01-01

Full Text Available Visual prosthesis applying electrical stimulation to restore visual function for the blind has promising prospects. However, due to the low resolution, limited visual field, and the low dynamic range of the visual perception, huge loss of information occurred when presenting daily scenes. The ability of object recognition in real-life scenarios is severely restricted for prosthetic users. To overcome the limitations, optimizing the visual information in the simulated prosthetic vision has been the focus of research. This paper proposes two image processing strategies based on a salient object detection technique. The two processing strategies enable the prosthetic implants to focus on the object of interest and suppress the background clutter. Psychophysical experiments show that techniques such as foreground zooming with background clutter removal and foreground edge detection with background reduction have positive impacts on the task of object recognition in simulated prosthetic vision. By using edge detection and zooming technique, the two processing strategies significantly improve the recognition accuracy of objects. We can conclude that the visual prosthesis using our proposed strategy can assist the blind to improve their ability to recognize objects. The results will provide effective solutions for the further development of visual prosthesis.

Optimization of Visual Information Presentation for Visual Prosthesis

Science.gov (United States)

Gao, Yong

2018-01-01

Visual prosthesis applying electrical stimulation to restore visual function for the blind has promising prospects. However, due to the low resolution, limited visual field, and the low dynamic range of the visual perception, huge loss of information occurred when presenting daily scenes. The ability of object recognition in real-life scenarios is severely restricted for prosthetic users. To overcome the limitations, optimizing the visual information in the simulated prosthetic vision has been the focus of research. This paper proposes two image processing strategies based on a salient object detection technique. The two processing strategies enable the prosthetic implants to focus on the object of interest and suppress the background clutter. Psychophysical experiments show that techniques such as foreground zooming with background clutter removal and foreground edge detection with background reduction have positive impacts on the task of object recognition in simulated prosthetic vision. By using edge detection and zooming technique, the two processing strategies significantly improve the recognition accuracy of objects. We can conclude that the visual prosthesis using our proposed strategy can assist the blind to improve their ability to recognize objects. The results will provide effective solutions for the further development of visual prosthesis. PMID:29731769

Musculocutaneous nerve substituting for the distal part of radial nerve: A case report and its embryological basis

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A S Yogesh

2011-01-01

Full Text Available In the present case, we have reported a unilateral variation of the radial and musculocutaneous nerves on the left side in a 64-year-old male cadaver. The radial nerve supplied all the heads of the triceps brachii muscle and gave cutaneous branches such as lower lateral cutaneous nerve of the arm and posterior cutaneous nerve of forearm. The radial nerve ended without continuing further. The musculocutaneous nerve supplied the brachioradialis, extensor carpi radialis longus and extensor carpi radialis brevis muscles. The musculocutaneous nerve divided terminally into two branches, superficial and deep. The deep branch of musculocutaneous nerve corresponded to usual deep branch of the radial nerve while the superficial branch of musculocutaneous nerve corresponded to usual superficial branch of the radial nerve. The dissection was continued to expose the entire brachial plexus from its origin and it was found to be normal. The structures on the right upper limb were found to be normal. Surgeons should keep such variations in mind while performing the surgeries of the upper limb.

21 CFR 878.3750 - External prosthesis adhesive.

Science.gov (United States)

2010-04-01

... used to fasten to the body an external aesthetic restoration prosthesis, such as an artificial nose. (b) Classification. Class I (general controls). The device is exempt from the premarket notification procedures in...

Development of a cosmetic knee disarticulation prosthesis : A single-patient case study

NARCIS (Netherlands)

de Laat, Fred A.; de Vos, Wouter; Geertzen, Jan; Roorda, Leo D.

2015-01-01

Background and aim: If a person does not become ambulant after an amputation, a knee disarticulation (KD) shouldbe considered and the person may then benefit from a cosmetic KD prosthesis. The features of a cosmetic KD prosthesis are, however, seldom described. The aim of this clinical note is to

21 CFR 888.3110 - Ankle joint metal/polymer semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ankle joint metal/polymer semi-constrained... Ankle joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an ankle...

Conception, design and development of a low-cost intelligent prosthesis for one-sided transfemoral amputees

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Wilson Carlos da Silva Júnior

Full Text Available Introduction Modern transfemoral knee prostheses are designed to offer comfort and self-confidence to amputees. These prostheses are mainly based upon either a passive concept, with a damping system, or an active computational intelligent design to control knee motion during the swing phase. In Brazil, most lower extremity amputees are unable to afford modern prostheses due to their high cost. In this work, we present the conception, design and development of a low-cost intelligent prosthesis for one-sided transfemoral amputees. Methods The concept of the prosthesis is based on a control system with sensors for loads, which are installed on the amputee’s preserved leg and used as a mirror for the movement of the prosthesis. Mechanical strength analysis, using the Finite Element Method, electromechanical tests for the sensors and actuators and verification of data acquisition, signal conditioning and data transferring to the knee prosthesis were performed. Results The laboratory tests performed showed the feasibility of the proposed design. The electromechanical concept that was used enabled a controlled activation of the knee prosthesis by the two load cells located on the shoe sole of the preserved leg. Conclusions The electromechanical design concept and the resulting knee prosthesis show promising results concerning prosthesis activation during walking tests, thereby showing the feasibility of a reduced manufacturing cost compared to the modern prostheses available on the market.

Self and partner satisfaction rates after 3 part inflatable penile prosthesis implantation.

Science.gov (United States)

Simsek, Abdulmuttalip; Kucuktopcu, Onur; Ozgor, Faruk; Ozkuvanci, Unsal; Baykal, Murat; Sarilar, Omer; Gurbuz, Zafer Gokhan

2014-09-30

To evaluate and present satisfaction rates of our patients and their partners after 3 part inflatable penile prosthesis implantation. We searched our hospital electronic data for patients who underwent inflatable penile prosthesis implantation between January 2008 and July 2013. Computer and archived file data were used to get information and reach the patients. We made telephone calls to patients and asked questionnaires about self and partner satisfaction rates. 36 patients underwent prosthesis implantation during the 5 year period. We were able to reach by telephone call 18 of them. The mean age of 18 patients was 55.7 ± 9.4 years and mean body mass index was 24.6 ± 2.1 kg/m2. The etiology was diabetes mellitus on 14 (77.8%) and radical pelvic surgery on 4 (22.2%) patients. 14 of 18 patients had penile Doppler ultrasound test. Doppler ultrasound demonstrated venous insufficiency in 8 and arterial insufficiency in 6 patients. Mean time from implantation to study was 20.8 ± 13.9 months. Out of 18 patients 2 had prosthesis removal operation because of infection in one patient and perforation in the other. Satisfaction rate was 88.9%, and recommendation rate was 94.4%. Causes of dissatisfaction were pain in one patient and insufficient rigidity plus shortening of the penis in the other one. Partner satisfaction rate was 94.4%. Penile Prosthesis Implantation (PPI) is the gold standard treatment of erectile dysfunction (ED) irresponsive to medical treatment. Infection and mechanical failure rates are going to be less according to the improvements in synthetic materials and coverings of the prosthesis, so patient and partner satisfaction rates will be higher.

A prosthesis-specific multi-link segment model of lower-limb amputee sprinting.

Science.gov (United States)

Rigney, Stacey M; Simmons, Anne; Kark, Lauren

2016-10-03

Lower-limb amputees commonly utilize non-articulating energy storage and return (ESAR) prostheses for high impact activities such as sprinting. Despite these prostheses lacking an articulating ankle joint, amputee gait analysis conventionally features a two-link segment model of the prosthetic foot. This paper investigated the effects of the selected link segment model׳s marker-set and geometry on a unilateral amputee sprinter׳s calculated lower-limb kinematics, kinetics and energetics. A total of five lower-limb models of the Ottobock ® 1E90 Sprinter were developed, including two conventional shank-foot models that each used a different version of the Plug-in-Gait (PiG) marker-set to test the effect of prosthesis ankle marker location. Two Hybrid prosthesis-specific models were then developed, also using the PiG marker-sets, with the anatomical shank and foot replaced by prosthesis-specific geometry separated into two segments. Finally, a Multi-link segment (MLS) model was developed, consisting of six segments for the prosthesis as defined by a custom marker-set. All full-body musculoskeletal models were tested using four trials of experimental marker trajectories within OpenSim 3.2 (Stanford, California, USA) to find the affected and unaffected hip, knee and ankle kinematics, kinetics and energetics. The geometry of the selected lower-limb prosthesis model was found to significantly affect all variables on the affected leg (p prosthesis-specific spatial, inertial and elastic properties from full-body models significantly affects the calculated amputee gait characteristics, and we therefore recommend the implementation of a MLS model. Copyright © 2016 Elsevier Ltd. All rights reserved.

Stability of radial and non-radial pulsation modes of massive ZAMS models

International Nuclear Information System (INIS)

Odell, A.P.; Pausenwein, A.; Weiss, W.W.; Hajek, A.

1987-01-01

The authors have computed non-adiabatic eigenvalues for radial and non-radial pulsation modes of star models between 80 and 120 M solar with composition of chi=0.70 and Z=0.02. The radial fundamental mode is unstable in models with mass greater than 95 M solar , but the first overtone mode is always stable. The non-radial modes are all stable for all models, but the iota=2 f-mode is the closest to being driven. The non-radial modes are progressively more stable with higher iota and with higher n (for both rho- and g-modes). Thus, their results indicate that radial pulsation limits the upper mass of a star

Maxillary palatal ramp prosthesis: A prosthodontic solution to manage mandibular deviation following surgery

Directory of Open Access Journals (Sweden)

Sampa Ray (Bhattacharya

2015-01-01

Full Text Available Mandibular resection following surgical treatment for neoplastic lesions of the oral cavity leads to numerous complications including altered mandibular movements, disfigurement, difficult in swallowing, impaired speech and articulation, and deviation of the mandible towards the resected site. Various prosthetic methods are employed to reduce or minimize mandibular deviation and improve and restore the lost functions and esthetic, like maxillomandibular fixation, implant supported prosthesis, removable mandibular guide flange prosthesis, and palatal based guidance restoration. This clinical report describes the rehabilitation of a patient following segmental mandibulectomy using palatal ramp prosthesis.

Donor-site morbidity of the radial forearm free flap versus the ulnar forearm free flap.

Science.gov (United States)

Hekner, Dominique D; Abbink, Jan H; van Es, Robert J; Rosenberg, Antoine; Koole, Ronald; Van Cann, Ellen M

2013-08-01

Donor-site morbidity following harvest of the radial forearm free flap was compared with that following harvest of the ulnar forearm free flap. Twenty-eight radial forearm and 27 ulnar forearm flaps were harvested in 55 patients with head and neck defects. Pressure perception was measured with Semmes-Weinstein monofilaments. Cold perception was tested with chloroethyl. Donor-site healing was evaluated. Patients were interviewed about grip and pinch strength and donor-site appearance. In the radial forearm free flap group, pressure perception and cold perception were reduced in the donor hand, whereas in the ulnar group, no differences were observed between the donor and unoperated hands. In the radial forearm group, 15 percent of patients experienced reduced strength in the donor hand, whereas in the ulnar forearm group, none of the patients reported reduced strength in the donor hand. In the radial forearm group, 14 percent had partial or complete loss of the skin graft, whereas in the ulnar forearm group, 4 percent had partial loss of the skin graft. In the radial forearm group, 18 percent of patients were dissatisfied with the appearance of the donor site, and no complaints were reported in the ulnar forearm group. The authors' study shows less donor site-morbidity following harvest of the ulnar forearm free flap than following harvest of the radial forearm free flap. These results emphasize that the ulnar forearm free flap should be considered as an alternative for the radial forearm free flap for reconstruction of soft-tissue defects. Therapeutic, III.

A new and simple method of fabrication of tracheostomal prosthesis

Directory of Open Access Journals (Sweden)

N Vidya Sankari

2015-01-01

Full Text Available Patients with a tracheostomy stoma experience compromised speech and function due to the associated changes in airflow patterns. Rehabilitation of a patient with tracheal stoma is a highly challenging task. The main objective is to design an inexpensive, easily fabricated stomal prosthesis for postlaryngectomy patients who require prolonged tracheotomy. This clinical case report describes a 29-year-old male patient who underwent for tracheotomy 3 months before for respiratory distress following a suicidal attempt. Hence tracheotomy was done, and the patient has been with the tracheostomal tube since surgery for the past 3 months. Laryngoscopy examination reported as restricted bilateral vocal cord movements, and the cords were in the adducted position with minimal glottic chink. No history of difficulty in swallowing. On examination, no scar or ulceration is seen around the stoma. The skin around the stoma is healthy. The patient was referred to the oral and maxillofacial Prosthodontics Department from the Department of ENT. The patient′s old tracheostomal tube was used as the dimensions of the custom made tracheal prosthesis without making a functional impression of the mature stoma. A tracheal button was made with 2 mm polyethylene urethane sheet to maintain the airway patency of the mature stoma. Width and length of the old tracheostomal tube were measured and customized with polyurethane sheet by directly flaming over heat. The finished product was thin, flexible, maintains enhanced tear strength, require no tapes or adhesives and less technique sensitive. These properties of the prosthesis make more advantageous than the commercially available tracheal buttons. The result in this patient was excellent with no postoperative complications. An innovative approach for fabrication of tracheostomal prosthesis was discussed to increase its successful use in tracheostomal patients. The patient′s old tracheostomal tube was used as the dimensions

Game-Based Rehabilitation for Myoelectric Prosthesis Control.

Science.gov (United States)

Prahm, Cosima; Vujaklija, Ivan; Kayali, Fares; Purgathofer, Peter; Aszmann, Oskar C

2017-02-09

A high number of upper extremity myoelectric prosthesis users abandon their devices due to difficulties in prosthesis control and lack of motivation to train in absence of a physiotherapist. Virtual training systems, in the form of video games, provide patients with an entertaining and intuitive method for improved muscle coordination and improved overall control. Complementary to established rehabilitation protocols, it is highly beneficial for this virtual training process to start even before receiving the final prosthesis, and to be continued at home for as long as needed. The aim of this study is to evaluate (1) the short-term effects of a commercially available electromyographic (EMG) system on controllability after a simple video game-based rehabilitation protocol, and (2) different input methods, control mechanisms, and games. Eleven able-bodied participants with no prior experience in EMG control took part in this study. Participants were asked to perform a surface EMG test evaluating their provisional maximum muscle contraction, fine accuracy and isolation of electrode activation, and endurance control over at least 300 seconds. These assessments were carried out (1) in a Pregaming session before interacting with three EMG-controlled computer games, (2) in a Postgaming session after playing the games, and (3) in a Follow-Up session two days after the gaming protocol to evaluate short-term retention rate. After each game, participants were given a user evaluation survey for the assessment of the games and their input mechanisms. Participants also received a questionnaire regarding their intrinsic motivation (Intrinsic Motivation Inventory) at the end of the last game. Results showed a significant improvement in fine accuracy electrode activation (Pgames when collecting items and facing challenging game play. Most upper limb amputees use a 2-channel myoelectric prosthesis control. This study demonstrates that this control can be effectively trained by

An Underreported Consequence of Obesity in Pregnancy: Patient-Prosthesis Mismatch

OpenAIRE

Hartman, William R.; Arendt, Katherine W.; Rehfeldt, Kent H.

2012-01-01

As the rate of obesity increases in childbearing-aged women, so too will the complications of obesity in pregnancy. An uncommon and likely underreported complication occurs in obese women who have received prepregnancy cardiac valve replacement with a prosthesis that is inadequately sized for body habitus, a condition referred to as patient-prosthesis mismatch (PPM). The physiologic changes of pregnancy as well as the increased weight gain combine to exacerbate PPM. We report a case of PPM th...

A custom-made temporomandibular joint prosthesis for fabrication by selective laser melting: Finite element analysis.

Science.gov (United States)

Xu, Xiangliang; Luo, Danmei; Guo, Chuanbin; Rong, Qiguo

2017-08-01

A novel and custom-made selective laser melting (SLM) 3D-printed alloplastic temporomandibular joint (TMJ) prosthesis is proposed. The titanium-6aluminium-4vanadium (Ti-6Al-4V) condyle component and ultra-high molecular weight polyethylene (UHMWPE) fossa component comprised the total alloplastic TMJ replacement prosthesis. For the condyle component, an optimized tetrahedral open-porous scaffold with combined connection structures, i.e. an inlay rod and an onlay plate, between the prosthesis and remaining mandible was designed. The trajectory of movement of the intact condyle was assessed via kinematic analysis to facilitate the design of the fossa component. The behaviours of the intact mandible and mandible with the prosthesis were compared. The biomechanical behaviour was analysed by assessing the stress distribution on the prosthesis and strain distribution on the mandible. After muscle force was applied, the magnitude of the compressive strain on the condyle neck of the mandible with the prosthesis was lower than that on the condyle neck of the intact mandible, with the exception of the area about the screws; additionally, the magnitude of the strain at the scaffold-bone interface was relatively high. Copyright © 2017. Published by Elsevier Ltd.

Elektra prosthesis for trapeziometacarpal osteoarthritis

DEFF Research Database (Denmark)

Klahn, A; Nygaard, Mads; Gvozdenovic, R

2012-01-01

We present a prospective follow-up of 39 Elektra prostheses in 37 patients (32 women and five men), with a mean age of 56.5 (range 46-71) years; 34 patients had osteoarthritis and three had rheumatoid arthritis. Patients were followed using clinical examination, including measurement of pain...... be the key problem in treating trapeziometacarpal osteoarthritis using a total prosthesis....

A unique method of retaining orbital prosthesis with attachment systems - a clinical report.

Science.gov (United States)

Guttal, Satyabodh S; Akash, N R; Prithviraj, D R; Lekha, K

2014-06-01

Diminution of the orbital contents post-surgical removal of a malignant tumor can have a severe psychological impact on the patient in terms of function and esthetics. Therefore, esthetic remedy should be planned subsequently, since tumor obliteration precedes cosmetic concern. A convenient option for successful rehabilitation in such patients is a simple, user-friendly, removable orbital prosthesis. Retention of the prosthesis is one of the key factors for the successful rehabilitation. Spectacle frame, conformers, adhesives, osseointegrated implants, magnets or buttons have been used to impart retention to the prosthesis. The use of semi precision attachments in maxillofacial prostheses is limited to the osseointegrated prostheses. This case report describes a conventional spectacle frame technique, to retain the silicone orbital prosthesis using two different types of stud attachments viz., dalla bona and O-ring attachment systems. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Customization of stock eye prosthesis for a pediatric patient by a simplified technique.

Science.gov (United States)

Jurel, Sunit Kumar; Talwar, Naina; Chand, Pooran; Singh, Raghuwar D; Gupta, Durga Shanker

2012-05-01

The unfortunate loss or absence of an eye may be caused by congenital defect , irreparable trauma, tumor or blind eye. The role of the maxillofacial prosthodontist in fabricating an ocular prosthesis to restore facial symmetry and normal appearance for the anophthalmic patient becomes essential. A custom-made ocular prosthesis is an excellent alternative for the people who lose their eye especially in young age. It has acceptable fit, retention and esthetics but is technically difficult to fabricate. On the other hand the stock eye has compromised fit and poor esthetics. Our case report presents a simple technique of customization of stock eye prosthesis to provide accurate fit and acceptable esthetics. How to cite this article: Jurel SK, Talwar N, Chand P, Singh RD, Gupta DS. Customization of Stock Eye Prosthesis for a Pediatric Patient by a Simplified Technique. Int J Clin Pediatr Dent 2012;5(2):155-158.

Difference in occurrence of heterotopic ossification according to prosthesis type in the cervical artificial disc replacement.

Science.gov (United States)

Yi, Seong; Kim, Keung Nyun; Yang, Moon Sul; Yang, Joong Won; Kim, Hoon; Ha, Yoon; Yoon, Do Heum; Shin, Hyun Chul

2010-07-15

Retrospective study of the difference of heterotopic ossification (HO) occurrence according to 3 different types of prosthesis. This study was designed to investigate the difference of HO occurrence according to different type of prosthesis. HO is defined as formation of the bone outside the skeletal system. Reported HO occurrence rate in cervical artificial disc replacement (ADR) was unexpectedly high and varied. But the influencing factors of HO in cervical ADR have not been elucidated well. The prosthesis-related factors for making difference of HO occurrence were investigated in this study. A total of 170 patients undergoing cervical arthroplasty with the Bryan cervical disc prosthesis (Medtroic Sofamor Danek, Memphis, TN), Mobi-C disc prosthesis (LDR Medical, Troyes, France), and ProDisc-C (Synthes, Inc., West Chester, PA) were included. Cervical lateral radiographs obtained before and after surgery were used to identify HO. Occurrence rate, occurrence-free period, location, and grade of HOs were investigated according to the different prosthesis. Each prosthesis group included patients as follows: Bryan disc, 81 patients; Mobi-C, 61 patients; and ProDisc-C, 28 patients. Overall HO rate was 40.6% (69 of 170 patients). Each HO occurrence rate by prosthesis was as follows: the Bryan disc group, 21.0%; Mobi-C group, 52.5%; and the ProDisc-C group, 71.4%. In the survival analysis, all patients showed 27.1 +/- 3.7 months as the median survival. The Bryan disc group showed statistically longer survival (48.4 +/- 7.4 months) than the other groups. Occurrence of HO is an inevitable postoperative complication after cervical ADR. The occurrence rate of HO was higher than our expectation. Moreover, definite differences in occurrence rate according to the prosthesis type were identified by this study.

Influence of type of aortic valve prosthesis on coronary blood flow velocity.

Science.gov (United States)

Jelenc, Matija; Juvan, Katja Ažman; Medvešček, Nadja Tatjana Ružič; Geršak, Borut

2013-02-01

Severe aortic valve stenosis is associated with high resting and reduced hyperemic coronary blood flow. Coronary blood flow increases after aortic valve replacement (AVR); however, the increase depends on the type of prosthesis used. The present study investigates the influence of type of aortic valve prosthesis on coronary blood flow velocity. The blood flow velocity in the left anterior descending coronary artery (LAD) and the right coronary artery (RCA) was measured intraoperatively before and after AVR with a stentless bioprosthesis (Sorin Freedom Solo; n = 11) or a bileaflet mechanical prosthesis (St. Jude Medical Regent; n = 11). Measurements were made with an X-Plore epicardial Doppler probe (Medistim, Oslo, Norway) following induction of hyperemia with an adenosine infusion. Preoperative and postoperative echocardiography evaluations were used to assess valvular and ventricular function. Velocity time integrals (VTI) were measured from the Doppler signals and used to calculate the proportion of systolic VTI (SF), diastolic VTI (DF), and normalized systolic coronary blood flow velocities (NSF) and normalized diastolic coronary blood flow velocities (NDF). The systolic proportion of the LAD VTI increased after AVR with the St. Jude Medical Regent prosthesis, which produced higher LAD SF and NSF values than the Sorin Freedom Solo prosthesis (SF, 0.41 ± 0.09 versus 0.29 ± 0.13 [P = .04]; NSF, 0.88 ± 0.24 versus 0.55 ± 0.17 [P = .01]). No significant changes in the LAD velocity profile were noted after valve replacement with the Sorin Freedom Solo, despite a significant reduction in transvalvular gradient and an increase in the effective orifice area. AVR had no effect on the RCA flow velocity profile. The coronary flow velocity profile in the LAD was significantly influenced by the type of aortic valve prosthesis used. The differences in the LAD velocity profile probably reflect differences in valve design and the systolic transvalvular flow pattern.

Self and partner satisfaction rates after 3 part inflatable penile prosthesis implantation

Directory of Open Access Journals (Sweden)

Abdulmuttalip Simsek

2014-09-01

Full Text Available Objective: To evaluate and present satisfaction rates of our patients and their partners after 3 part inflatable penile prosthesis implantation. Materials and methods: We searched our hospital electronic data for patients who underwent inflatable penile prosthesis implantation between January 2008 and July 2013. Computer and archived file data were used to get information and reach the patients. We made telephone calls to patients and asked questionnaires about self and partner satisfaction rates. Results: 36 patients underwent prosthesis implantation during the 5 year period. We were able to reach by telephone call 18 of them. The mean age of 18 patients was 55.7 ± 9.4 years and mean body mass index was 24.6 ± 2.1 kg/m2. The etiology was diabetes mellitus on 14 (77.8% and radical pelvic surgery on 4 (22.2% patients. 14 of 18 patients had penile Doppler ultrasound test. Doppler ultrasound demonstrated venous insufficiency in 8 and arterial insufficiency in 6 patients. Mean time from implantation to study was 20.8 ± 13.9 months. Out of 18 patients 2 had prosthesis removal operation because of infection in one patient and perforation in the other. Satisfaction rate was 88.9%, and recommendation rate was 94.4%. Causes of dissatisfaction were pain in one patient and insufficient rigidity plus shortening of the penis in the other one. Partner satisfaction rate was 94.4%. Conclusion: Penile Prosthesis Implantation (PPI is the gold standard treatment of erectile dysfunction (ED irresponsive to medical treatment. Infection and mechanical failure rates are going to be less according to the improvements in synthetic materials and coverings of the prosthesis, so patient and partner satisfaction rates will be higher.

Hip arthroplasty. Part 1: prosthesis terminology and classification

International Nuclear Information System (INIS)

Pluot, E.; Davis, E.T.; Revell, M.; Davies, A.M.; James, S.L.J.

2009-01-01

Hip arthroplasty is an extremely common orthopaedic procedure and there is a wide array of implants that are in current use in the UK. The follow-up of patients who have undergone insertion of a hip prosthesis is shifting from a consultant-lead hospital service towards primary care. As this change in patient care continues it becomes increasingly important that an accurate description of the radiographic features is communicated to the primary-care practitioner so appropriate specialist input can be triggered. This review focuses on the terminology and classification of hip prostheses. This acts as a precursor for Part 2 of this series, which describes the normal and abnormal radiographic findings following hip prosthesis insertion.

A Biomimetic Approach for Designing a Full External Breast Prosthesis: Post-Mastectomy

Directory of Open Access Journals (Sweden)

Pedro Cruz

2018-03-01

Full Text Available This work presents the design of a new breast prosthesis using the biomimetic technique for cases of complete mastectomy to address the problem of the increasing number of women diagnosed with breast cancer in Mexico who are candidates for a mastectomy. The designed prosthesis considers the morphology of a real breast regarding its internal structure to obtain authentic mobility and feel. In order to accomplish this, a model was obtained in 3D CAD using a coordinate measuring machine (CMM that can be scalable without losing its qualities, and which can be used in any type of patient; afterwards, a finite element model was developed and a static analysis performed with suggested load cases to evaluate the sensitivity and naturalness of the prosthesis; and finally, a modal analysis was conducted. The results obtained in displacements and in distribution of stress for the load cases assessed are consistent with those of a real breast: there were smooth contours and there was natural mobility in the prosthesis designed by means of the biomimetic technique.

21 CFR 888.3565 - Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellofemorotibial metal/polymer... Devices § 888.3565 Knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis. (a) Identification. A knee joint patellofemorotibial metal/polymer porous-coated uncemented prosthesis is a device...

21 CFR 888.3550 - Knee joint patellofemorotibial polymer/metal/metal constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellofemorotibial polymer/metal/metal... § 888.3550 Knee joint patellofemorotibial polymer/metal/metal constrained cemented prosthesis. (a) Identification. A knee joint patellofemorotibial polymer/metal/metal constrained cemented prosthesis is a device...

21 CFR 888.3490 - Knee joint femorotibial metal/composite non-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/composite non... § 888.3490 Knee joint femorotibial metal/composite non-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/composite non-constrained cemented prosthesis is a device...

A cascade model of information processing and encoding for retinal prosthesis.

Science.gov (United States)

Pei, Zhi-Jun; Gao, Guan-Xin; Hao, Bo; Qiao, Qing-Li; Ai, Hui-Jian

2016-04-01

Retinal prosthesis offers a potential treatment for individuals suffering from photoreceptor degeneration diseases. Establishing biological retinal models and simulating how the biological retina convert incoming light signal into spike trains that can be properly decoded by the brain is a key issue. Some retinal models have been presented, ranking from structural models inspired by the layered architecture to functional models originated from a set of specific physiological phenomena. However, Most of these focus on stimulus image compression, edge detection and reconstruction, but do not generate spike trains corresponding to visual image. In this study, based on state-of-the-art retinal physiological mechanism, including effective visual information extraction, static nonlinear rectification of biological systems and neurons Poisson coding, a cascade model of the retina including the out plexiform layer for information processing and the inner plexiform layer for information encoding was brought forward, which integrates both anatomic connections and functional computations of retina. Using MATLAB software, spike trains corresponding to stimulus image were numerically computed by four steps: linear spatiotemporal filtering, static nonlinear rectification, radial sampling and then Poisson spike generation. The simulated results suggested that such a cascade model could recreate visual information processing and encoding functionalities of the retina, which is helpful in developing artificial retina for the retinally blind.

Eliciting Naturalistic Cortical Responses with a Sensory Prosthesis via Optimized Microstimulation

Science.gov (United States)

2016-08-12

Eliciting naturalistic cortical responses with a sensory prosthesis via optimized microstimulation John S Choi1, Austin J Brockmeier2, David B...applied to single electrodes in the ventral caudal thalamus evoke percepts that are both place and modality-specific, and yet ‘unnatural’ in feeling ...information on touch parameters, they do so with the same timing, as would be expected for a biomimetic sensory prosthesis . The discriminability of natural

Restoring Proprioception via a Cortical Prosthesis: A Novel Learning Based Approach

Science.gov (United States)

2016-10-01

AWARD NUMBER: W81XWH-14-1-0510 TITLE: Restoring Proprioception via a Cortical Prosthesis : A Novel Learning-Based Approach PRINCIPAL INVESTIGATOR...Sep 2015 - 29 Sep 2016 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Restoring Proprioception via a Cortical Prosthesis : A Novel Learning-Based...the feeling of where the body is in space. The importance of proprioception is often not appreciated; without it, we are unable to move normally

An experimental-numerical method for comparative analysis of joint prosthesis

International Nuclear Information System (INIS)

Claramunt, R.; Rincon, E.; Zubizarreta, V.; Ros, A.

2001-01-01

The difficulty that exists in the analysis of mechanical stresses in bones is high due to its complex mechanical and morphological characteristics. This complexity makes generalists modelling and conclusions derived from prototype tests very questionable. In this article a relatively simple comparative analysis systematic method that allow us to establish some behaviour differences in different kind of prosthesis is presented. The method, applicable in principle to any joint problem, is based on analysing perturbations produced in natural stress states of a bone after insertion of a joint prosthesis and combines numerical analysis using a 3-D finite element model and experimental studies based on photoelastic coating and electric extensometry. The experimental method is applied to compare two total hip prosthesis cement-free femoral stems of different philosophy. One anatomic of new generation, being of oblique setting over cancellous bone and the other madreporique of trochantero-diaphyseal support over cortical bone. (Author) 4 refs

21 CFR 888.3530 - Knee joint femorotibial metal/polymer semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/polymer semi... § 888.3530 Knee joint femorotibial metal/polymer semi-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/polymer semi-constrained cemented prosthesis is a device intended...

21 CFR 888.3540 - Knee joint patellofemoral polymer/metal semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellofemoral polymer/metal semi... § 888.3540 Knee joint patellofemoral polymer/metal semi-constrained cemented prosthesis. (a) Identification. A knee joint patellofemoral polymer/metal semi-constrained cemented prosthesis is a two-part...

21 CFR 888.3500 - Knee joint femorotibial metal/composite semi-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/composite semi... § 888.3500 Knee joint femorotibial metal/composite semi-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/composite semi-constrained cemented prosthesis is a two-part...

21 CFR 888.3590 - Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint tibial (hemi-knee) metallic resurfacing... Knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint tibial (hemi-knee) metallic resurfacing uncemented prosthesis is a device intended to be implanted...

21 CFR 888.3520 - Knee joint femorotibial metal/polymer non-constrained cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint femorotibial metal/polymer non... § 888.3520 Knee joint femorotibial metal/polymer non-constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metal/polymer non-constrained cemented prosthesis is a device intended to...

21 CFR 888.3580 - Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Knee joint patellar (hemi-knee) metallic... § 888.3580 Knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis. (a) Identification. A knee joint patellar (hemi-knee) metallic resurfacing uncemented prosthesis is a device made of...

Validation of a standardized mapping system of the hip joint for radial MRA sequencing

International Nuclear Information System (INIS)

Klenke, Frank M.; Hoffmann, Daniel B.; Cross, Brian J.; Siebenrock, Klaus A.

2015-01-01

Intraarticular gadolinium-enhanced magnetic resonance arthrography (MRA) is commonly applied to characterize morphological disorders of the hip. However, the reproducibility of retrieving anatomic landmarks on MRA scans and their correlation with intraarticular pathologies is unknown. A precise mapping system for the exact localization of hip pathomorphologies with radial MRA sequences is lacking. Therefore, the purpose of the study was the establishment and validation of a reproducible mapping system for radial sequences of hip MRA. Sixty-nine consecutive intraarticular gadolinium-enhanced hip MRAs were evaluated. Radial sequencing consisted of 14 cuts orientated along the axis of the femoral neck. Three orthopedic surgeons read the radial sequences independently. Each MRI was read twice with a minimum interval of 7 days from the first reading. The intra- and inter-observer reliability of the mapping procedure was determined. A clockwise system for hip MRA was established. The teardrop figure served to determine the 6 o'clock position of the acetabulum; the center of the greater trochanter served to determine the 12 o'clock position of the femoral head-neck junction. The intra- and inter-observer ICCs to retrieve the correct 6/12 o'clock positions were 0.906-0.996 and 0.978-0.988, respectively. The established mapping system for radial sequences of hip joint MRA is reproducible and easy to perform. (orig.)

Usefulness of positron emission tomography (TEP) in the assessment of osteo-articular prosthesis

International Nuclear Information System (INIS)

Maldonado, A.; Suarez, J.P.; Dominguez, M.L.

2004-01-01

Joint arthroplasty is performed with increasing frequency as the population ages. Loosening or infection of the prosthesis is a relatively common event that can limit the lifetime of a prosthesis. Accuracy differentiation between aseptic and septic loosening of the prosthesis remains a challenge because of the consequences for patient management. Moreover, an early diagnosis of infected hip prosthesis is very important for optimal and cost-effective management. Various approaches have developed to visualize infection and inflammation by nuclear medicine techniques. Recently positron emission tomography (PET) with fluorine-l8 labelled 2 fluoro-2-deoxyglucose ( 18 F-FDG) has been shown to delineate infectious and inflammatory foci with high sensitivity owing to the increased glucose metabolism in inflammatory cells. In this paper we review the role of FDG-PET in this common differential diagnosis in patients with total knee and hip prostheses. Different patterns of FDG-PET interpretation have been described as wed as methodological aspects. (author)

[Phonomechanocardiography in the evaluation of the functional status of valvular prosthesis].

Science.gov (United States)

Esquivel Avila, J; Molina Zapata, B; Martínez Ríos, M A; Flamand, E

1975-01-01

The FMCG in 22 patients with valvular prosthesis is analyzed and its clinical, hemodynamic and surgical correlation are established (11 from the I.N.C. and 11 from the Hospital Infantil I.M.A.N.). The average age of the patients was 15 years old, 18 had a mitral and six aortic valvulopathy, and they all required a valvular replacement. Of the mitral prosthesis, 14 were Starr-Edwards (13 of ball valve and one of disc), three Lillehei-Kaster and one Börck-Shiley. In 5 patients, the FMCG suspected disfunction that was later corroborated by catheterism in three patients and by surgery in all of them. The important differences of the FMCG between the group with good and the one with bad function were: the aparition of a rumble, a decrease in the amplitud of the closing snap, index of closing snap opering snap of less than one, lenghtening of fases PFVP and IVCP, and shortening of IVDRP. In the patients with auricular fibrilation, after long dyastoles; that would represent an adequate atrial emptying; the closing snap was more intense, the PFVP was lennthened the IVDRP was shortened when the prosthesis was not properly functioning. All the aortic prosthesis were ball valve Starr-Edwards type; in one the FMCG suspected disfunction and the patient had a sudden death outside of the Hospital. The significant differences of the FMCG were the decrease in the intensity of the opening snap, with a Hylen index of less than one, lengthening of the PFVP, IVCP and of the expulsive period (EP). The authors conclude that the FMCG is a good method for an early detection of the disfunctions of valvular prosthesis.

A case report of an isolated fracture through the radial bicipital tuberosity

Directory of Open Access Journals (Sweden)

Kanta Imao

Full Text Available Introduction: Generally, anatomical reduction of shaft fractures through operative treatment is necessary to restore the anatomical relationship of the forearm bones. However, a number of nerves and vessels are located in the proximal radius, which complicates surgery. In this study, we aimed to reduce postoperative complications by using a posterior approach. Presentation of case: We describe an isolated fracture through the radial bicipital tuberosity in a 69-year-old man caused by direct blunt force and our management of the fracture. The patient underwent an operation for the fracture under brachial plexus block. The injury was explored using the posterior approach, and plate fixation was performed after confirming the absence of obstacles to rotation on pronation and supination. One year later, the patient did not have any difficulties in activities of daily living. Discussion: Since an isolated fracture through the radial bicipital tuberosity is more distal than the radial head and neck and more proximal than a common radius diaphysis fracture, we had to consider a different operative approach. The nerve and blood vessels of the forearm, such as the radial nerve and artery, run in a complicated fashion around the proximal radius; thus, we chose the posterior approach because of its simpler surgical technique and lower complication risk, compared with the anterior approach. Conclusion: Surgeons can obtain a favorable treatment result using the posterior approach to the fracture and reduce complications by ensuring with rigid fixation using a locking plate. Keywords: Radial bicipital tuberosity, Posterior approach, Posterior interosseous nerve, Shaft fracture

[Longterm results of cervical arthroplasty with disc prosthesis. A literature review].

Science.gov (United States)

Fransen, P; Schils, F

2014-01-01

Cervical arthroplasty has now been performed for over 10 years. Despite the large number of implanted artificial discs, the quality of the published studies is weak, and very few report a follow up exceeding two years. We reviewed the literature on cervical total disc replacement, focusing on publications reporting a follow-up of more than two years. The selection of patients, the type of implant and the surgical technique seem to influence greatly the quality of the clinical and radiological results. The occurrence of heterotopic ossifications around the implant seems to be the rule rather than the exception. Wear debris are likely to be observed in the vicinity of the prosthesis. Most long term studies also report a progressive decrease in the range of motion of the prosthesis, although without influence on the clinical evolution. It seems reasonable to say that cervical disc prosthesis is not inferior to discectomy and fusion, and that these implants allow a short term preservation of cervical mobility, but the efficacy in preventing adjacent segment disease or a favourable costleffectiveness ratio have yet to be demonstrated. A more widespread use of cervical disc prosthesis can only be suggested when these questions have been answered by long term follow-up studies.

Quality of life among lower limb prosthesis users attending Artificial Limb Center of Fauji Foundation Hospital Rawalpindi

International Nuclear Information System (INIS)

Kalsoom, U.; Bairam, S.

2018-01-01

To assess quality of life and the influencing factors as perceived by lower limb prosthesis users. Study Design: Cross sectional study. Place and Duration of Study: Artificial Limb Centre, Fauji Foundation Hospital Rawalpindi, 11 months (Jan to Nov 2014). Material and Methods: A sample of 50 patients with lower limb amputations and using lower limb prosthesis were recruited by applying inclusion criteria. Responses were recorded on demographic variables, reasons for amputation, time of provision of prosthesis, employment status etc. by the investigator on a structured pretested questionnaire after their consent. A p-value of <0.05 was taken as significant. Quality of life was interpreted on 5 point Likert scale. Data was analyzed in SPSS version 21. Result: Majority of respondents i.e. 17 (34%) were in 51-60 years age group with mean age 46 +- 14 years while 33 (66%) were males and 27 (54%) illiterate, 33 (66%) could afford a prosthesis. Trauma 28 (56%) was the most prevalent cause of lower limb amputation and among them 15 (53%) had road accident injuries. Various factors influenced quality of life as perceived by the respondents and in 10 (20%), 16 (32%), 25 (50%) social, family life and emotional status was affected respectively, while 14 (28%) of the prosthesis user were unemployed. Prosthesis were provided after 2 years in 18 (36%) and in 37 (74%) prosthesis were provided by the health care facility. Good quality of life was perceived in 40 (80%) respondents. Conclusion: Perceived Quality of life was good in majority of the prosthesis users but others can't be ignored. It can be improved by early provision of prosthesis which can help in better employment opportunities. (author)

Experimental Assessment of a New Type of Carbon-Coated ARTECOR® Vascular Prosthesis in Sheep

Directory of Open Access Journals (Sweden)

Jiří Podlaha

2009-01-01

Full Text Available The aim of the study was to test and verify the characteristics of a new type of carbon-coated ARTECOR® vascular prosthesis developed at the Knitting Research Institute, a.s. Brno. Eight healthy Merino sheep, aged between 2 and 3 years, were implanted four types (A, B, C with diamond-like carbon (DLC coating and D as a control without DLC of vascular prostheses. The site of implantation was the common carotid artery; the length of the implant was 7 cm. All sheep received antibiotics prophylactically in accordance with the theory of the so-called “protected coagulum”. Doppler ultrasound examination was performed before finishing the operation to verify the patency of each prosthesis. During the study period the animals were closely observed. Prostheses were extirpated on day +/- 100 in 6 sheep and on day 182 in 2 sheep. Type B prosthesis showed better results according to its postoperative patency. The implant lumen was constantly 7 mm, whereas the use of other types resulted in lumen narrowing. Type B prosthesis has a deposition of DLC coating of a thickness of 20 nm with a high content of sp3 bonds (more diamond-like ones. The experimental type B of prosthesis ARTECOR® appears to be the most successful of the tested prostheses (at the end of the study all B-type prostheses remained patent. This prosthesis appears to better satisfy the rheologic characteristics for healing.

Restoring Proprioception via a Cortical Prosthesis: A Novel Learning-Based Approach

Science.gov (United States)

2015-10-01

AWARD NUMBER: W81XWH-14-1-0510 TITLE: Restoring Proprioception via a Cortical Prosthesis : A Novel Learning-Based Approach PRINCIPAL INVESTIGATOR...Proprioception via a Cortical Prosthesis : A Novel Learning-Based Approach 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Philip Sabes, PhD 5d...component of this lost sensation is proprioception, the feeling of where the body is in space. The importance of proprioception is often not appreciated

Clinical experience with an alloplastic stoma prosthesis (Biocarbon) for urinary conduits and cutaneous ureterostomy.

Science.gov (United States)

Månsson, W; Harzmann, R

1988-01-01

An alloplastic stoma prosthesis, Biocarbon, composed of 99.9% pure carbon in vitreous form, was used in six patients with conduit urinary diversion and in seven with cutaneous ureterostomy. The patients were thereafter observed for 2-86 months. Complications were subcutaneous infection, urinary fistula and ureteral stenosis, which necessitated removal of the prosthesis in most cases. The permanent stoma, without need for adhesive collecting device, was appreciated by the patients. Problems relating to biocompatibility remain to be solved before the place of the stoma prosthesis in urinary diversion can be determined.

Radial transport in the far scrape-off layer of ASDEX upgrade during L-mode and ELMy H-mode

DEFF Research Database (Denmark)

Ionita, C.; Naulin, Volker; Mehlmann, F.

2013-01-01

The radial turbulent particle flux and the Reynolds stress in the scrape-off layer (SOL) of ASDEX Upgrade were investigated for two limited L-mode (low confinement) and one ELMy H-mode (high confinement) discharge. A fast reciprocating probe was used with a probe head containing five Langmuir...

Neck osteotomy for malunion of neglected radial neck fractures in children: a report of 2 cases.

Science.gov (United States)

Ceroni, Dimitri; Campos, José; Dahl-Farhoumand, Agnes; Holveck, Jérôme; Kaelin, André

2010-01-01

Radial neck fractures are a common injury in children as a result of a fall on an extended and supinated outstretched hand. We present 2 cases of osteotomy of the neck of the radius performed in 2 children with neglected radial neck fractures. Preoperatively, both patients complained of pain and severely reduced mobility of the elbow. Surgery was performed at 6 weeks and 3 months, respectively, after the initial injury and the 2 children were reviewed at 6 and 16 months follow-up. Osteotomies healed within the usual time and no avascular necrosis of the radial head, proximal radioulnar synostosis, or myositis ossificans were observed. The Mayo Elbow Performance Index Score improved significantly after the operation with the 2 patients rated as excellent. In this small series, we present a novel technique of proximal osteotomy of the radius to correct this deformity in children. Case series, level IV evidence.

Redesign of a Low Energy Probe Head

CERN Document Server

Rao, Yi-Nong; Ries, Thomas

2005-01-01

The present situation of the low energy probe LE2 in TRIUMF cyclotron is that the thickness of the finger 5 is uniform over a radial length of 3.25 inch and its weight which amounts to ~447 g is affecting its re-circulating ball mechanism and causing it to fall below the median plane over its range of movement. We therefore re-design it in order to reduce its weight. First, we made simulations and determined the optimum thickness of the probe head vs its radial length. These simulation results are found to be in good agreement with experimental measurements made. Finally, we calculated the temperature rise caused by the beam power dumped on the probe, and figured out the maximum current of beam that can be dumped on the finger.

Effect of breast augmentation after breast-conserving surgery for breast cancer on radiation dose. Silicone prosthesis and changes in radiation dose

International Nuclear Information System (INIS)

Tonari, Ayako; Nako, Yasunobu; Ikezaki, Hiromi; Maruyama, Yasushi; Ikeda, Ikuo; Kusuda, Junko; Harii, Kiyonori; Takayama, Makoto

2008-01-01

The results of a study simulating postoperative radiation therapy of remaining breast tissue with a silicone bag prosthesis implanted to examine the effects of the prosthesis on radiation dosage and surrounding tissue are reported. The evaluation was conducted in two stages: a water phantom was used to evaluate scattering effects of a prosthesis installed inside the phantom using glass rod detector (GRD) set around the prosthesis. Measurements were conducted on both entrance and rear sides of the prosthesis. A Rand phantom was used to measure radiation doses around the prosthesis. The first evaluation resulted in a less than 5.4% reduction in dose at the rear side of the prosthesis whereas the second evaluation, for opposing portal irradiation used with breast-conserving surgical treatment, showed the effects of the prosthesis on radiation dosage being within ±2%, the permitted treatment range. In conclusion, for treating breast cancer, combining surgical treatment of the cancer with implanting of prosthesis for breast reconstruction followed by radiation treatment appears feasible as no effects on dosage were observed on treatment effectiveness. (author)

A cognitive prosthesis for complex decision-making.

Science.gov (United States)

Tremblay, Sébastien; Gagnon, Jean-François; Lafond, Daniel; Hodgetts, Helen M; Doiron, Maxime; Jeuniaux, Patrick P J M H

2017-01-01

While simple heuristics can be ecologically rational and effective in naturalistic decision making contexts, complex situations require analytical decision making strategies, hypothesis-testing and learning. Sub-optimal decision strategies - using simplified as opposed to analytic decision rules - have been reported in domains such as healthcare, military operational planning, and government policy making. We investigate the potential of a computational toolkit called "IMAGE" to improve decision-making by developing structural knowledge and increasing understanding of complex situations. IMAGE is tested within the context of a complex military convoy management task through (a) interactive simulations, and (b) visualization and knowledge representation capabilities. We assess the usefulness of two versions of IMAGE (desktop and immersive) compared to a baseline. Results suggest that the prosthesis helped analysts in making better decisions, but failed to increase their structural knowledge about the situation once the cognitive prosthesis is removed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modular head assembly and method of retrofitting existing nuclear reactor facilities

International Nuclear Information System (INIS)

Malandra, L.J.; Ledue, R.J.; Hankinson, M.F.; Kowalski, E.F.

1987-01-01

A method is described of retrofitting existing nuclear reactor facilities so as to form a modular closure head assembly for a nuclear reactor pressure vessel, where the existing nuclear reactor facilities comprise control rod drive mechanism cooling systems which include vertically extending elbow air ducts inter-connecting vertically spaced upper and lower air manifolds. The elbow air ducts extend radially beyond the peripheral envelope of the closure head, comprising the steps of: removing the upper air manifold; removing the vertically extending elbow air ducts; capping the air ports of the lower air manifold which ports were previously fluidically connecting the lower air manifold to the vertically extending elbow air ducts; disposing vertically upwardly extending air exhaust ducts above the lower air manifold in such an manner that the air exhaust ducts are disposed within the peripheral envelope of the closure head; fluidically connecting exhaust fans to the upper regions of the air exhaust ducts; fluidically connecting the lower regions of the air exhaust ducts the lower air manifold; permanently securing lift rods to the closure head at positions disposed radially outwardly of the lower air manifold; attaching a seismic support platform to the lift rods; proving fluidic passage of the vertically extending air exhaust ducts through the seismic support platform; attaching a missile shield plate to the lift rods; and proving fluidic passage of the vertically extending air exhaust ducts through the missile shield plate

Stress distribution in dental prosthesis under an occlusal combined dynamic loading

International Nuclear Information System (INIS)

Merdji, A.; Bachir Bouiadjra, B.; Ould Chikh, B.; Mootanah, R.; Aminallah, L.; Serier, B.; Muslih, I.M.

2012-01-01

Highlights: ► The mechanical stress reaches the highest in areas of cortical bones. ► The mechanical stress in the cancellous bone reaches greatest in the bottom of the dental implant. ► Implant with low-volume bone might cause increased stress concentration in the cortical bone. -- Abstract: The biomechanical behavior of osseointegrated dental prostheses systems plays an important role in its functional longevity inside the bone. Simulation of these systems requires an accurate modeling of the prosthesis components, the jaw bone, the implant–bone interface, and the response of the system to different types of applied forces. The purpose of this study was to develop a new three-dimensional model of an osseointegrated molar dental prosthesis and to carry out finite element analysis to evaluate stress distributions in the bone and the dental prosthesis compounds under an occlusal combined dynamic load was applied to the top of the occlusale face of the prosthesis crown. The jaw bone model containing cortical bone and cancellous bone was constructed by using computer tomography scan pictures and Computer Aided Design tools. The dental prosthesis compounds were constructed, simulating the commercially available cylindrical implant of 4.8 mm diameter and 10 mm length. Both finite element models were created in Abaqus finite element software. All materials used in the models were considered to be isotropic, homogeneous and linearly elastic. The elastic properties, loads and constraints used in the model were taken from published data. Results of our finite element analyses, indicated that the maximum stresses were located around the mesial neck of the implant, in the marginal bone. Thus, this area should be preserved clinically in order to maintain the bone–implant interface structurally and functionally.

A simplified approach to fabrication of an ocular prosthesis: A case series

Directory of Open Access Journals (Sweden)

Kaur Amandeep

2010-01-01

Full Text Available The eye is a vital organ and an important component of facial expression. Loss of an eye has a crippling effect on the psychology of the patient. Enucleation of the eye is therefore normally followed by fabrication of an ocular prosthesis to improve esthetics. A less complex technique for fabrication of an ocular prosthesis is described in this report of two different cases.

Visual prosthesis wireless energy transfer system optimal modeling.

Science.gov (United States)

Li, Xueping; Yang, Yuan; Gao, Yong

2014-01-16

Wireless energy transfer system is an effective way to solve the visual prosthesis energy supply problems, theoretical modeling of the system is the prerequisite to do optimal energy transfer system design. On the basis of the ideal model of the wireless energy transfer system, according to visual prosthesis application condition, the system modeling is optimized. During the optimal modeling, taking planar spiral coils as the coupling devices between energy transmitter and receiver, the effect of the parasitic capacitance of the transfer coil is considered, and especially the concept of biological capacitance is proposed to consider the influence of biological tissue on the energy transfer efficiency, resulting in the optimal modeling's more accuracy for the actual application. The simulation data of the optimal model in this paper is compared with that of the previous ideal model, the results show that under high frequency condition, the parasitic capacitance of inductance and biological capacitance considered in the optimal model could have great impact on the wireless energy transfer system. The further comparison with the experimental data verifies the validity and accuracy of the optimal model proposed in this paper. The optimal model proposed in this paper has a higher theoretical guiding significance for the wireless energy transfer system's further research, and provide a more precise model reference for solving the power supply problem in visual prosthesis clinical application.

False-positive indium-111 labeled leukocyte scintigram in a patient with a painful hip prosthesis

International Nuclear Information System (INIS)

Feldman, N.; Makler, P.T. Jr.; Alavi, A.

1986-01-01

A Tronzo hip prosthesis is designed to elicit an inflammatory reaction in order to promote prosthesis stability. A three-phased bone scan and Ga-67 imaging in conjunction with physical examination and laboratory findings failed to demonstrate evidence for osteomyelitis in a patient with a painful hip prosthesis, in whom images obtained with In-111-labeled leukocytes were positive. This observation demonstrated that the interpretation of the latter technique in demonstrating inflammation can cause a false impression of an infectious process

Nontraumatic Fracture of the Femoral Condylar Prosthesis in a Total Knee Arthroplasty Leading to Mechanical Failure

Directory of Open Access Journals (Sweden)

Girish N. Swamy

2014-01-01

Full Text Available This paper reports a case of fatigue fracture of the femoral component in a cruciate-retaining cemented total knee arthroplasty (TKA. A 64-year-old man had undergone a primary TKA for osteoarthritis 10 years previously at another institution using the PFC-Sigma prosthesis. The patient recovered fully and was back to his regular activities. He presented with a history of sudden onset pain and locking of the left knee since the preceding three months. There was no history of trauma, and the patient was mobilizing with difficulty using crutches. Radiographs revealed fracture of the posterior condyle of the femoral prosthesis. Revision surgery was performed as an elective procedure revealing the broken prosthesis. The TC3RP-PFC revision prosthesis was used with a medial parapatellar approach. The patient recovered fully without any squeal. Mechanical failure of the knee arthroplasty prosthesis is rare, and nontraumatic fracture of the femoral metallic component has not been reported before.

Nontraumatic fracture of the femoral condylar prosthesis in a total knee arthroplasty leading to mechanical failure.

Science.gov (United States)

Swamy, Girish N; Quah, Conal; Bagouri, Elmunzar; Badhe, Nitin P

2014-01-01

This paper reports a case of fatigue fracture of the femoral component in a cruciate-retaining cemented total knee arthroplasty (TKA). A 64-year-old man had undergone a primary TKA for osteoarthritis 10 years previously at another institution using the PFC-Sigma prosthesis. The patient recovered fully and was back to his regular activities. He presented with a history of sudden onset pain and locking of the left knee since the preceding three months. There was no history of trauma, and the patient was mobilizing with difficulty using crutches. Radiographs revealed fracture of the posterior condyle of the femoral prosthesis. Revision surgery was performed as an elective procedure revealing the broken prosthesis. The TC3RP-PFC revision prosthesis was used with a medial parapatellar approach. The patient recovered fully without any squeal. Mechanical failure of the knee arthroplasty prosthesis is rare, and nontraumatic fracture of the femoral metallic component has not been reported before.

Carbon/PEEK composite materials as an alternative for stainless steel/titanium hip prosthesis: a finite element study.

Science.gov (United States)

Rezaei, Farshid; Hassani, Kamran; Solhjoei, Nosratollah; Karimi, Alireza

2015-12-01

Total hip replacement (THR) has been ranked within the most typical surgical processes in the world. The durability of the prosthesis and loosening of prosthesis are the main concerns that mostly reported after THR surgeries. In THR, the femoral prosthesis can be fixed by either cement or cementless methods in the patient's bones. In both procedures, the stability of the prosthesis in the hosted bone has a key asset in its long-term durability and performance. This study aimed to execute a comparative finite element simulation to assess the load transfer between the prosthesis, which is made of carbon/PEEK composite and stainless steel/titanium, and the femur bone. The mechanical behavior of the cortical bone was assumed as a linear transverse isotropic while the spongy bone was modeled like a linear isotropic material. The implants were made of stainless steel (316L) and titanium alloy as they are common materials for implants. The results showed that the carbon/PEEK composites provide a flatter load transfer from the upper body to the leg compared to the stainless steel/titanium prosthesis. Furthermore, the results showed that the von Mises stress, principal stress, and the strain in the carbon/PEEK composites prosthesis were significantly lower than that made of the stainless steel/titanium. The results also imply that the carbon/PEEK composites can be applied to introduce a new optimum design for femoral prosthesis with adjustable stiffness, which can decrease the stress shielding and interface stress. These findings will help clinicians and biomedical experts to increase their knowledge about the hip replacement.

Radial polar histogram: obstacle avoidance and path planning for robotic cognition and motion control

Science.gov (United States)

Wang, Po-Jen; Keyawa, Nicholas R.; Euler, Craig

2012-01-01

In order to achieve highly accurate motion control and path planning for a mobile robot, an obstacle avoidance algorithm that provided a desired instantaneous turning radius and velocity was generated. This type of obstacle avoidance algorithm, which has been implemented in California State University Northridge's Intelligent Ground Vehicle (IGV), is known as Radial Polar Histogram (RPH). The RPH algorithm utilizes raw data in the form of a polar histogram that is read from a Laser Range Finder (LRF) and a camera. A desired open block is determined from the raw data utilizing a navigational heading and an elliptical approximation. The left and right most radii are determined from the calculated edges of the open block and provide the range of possible radial paths the IGV can travel through. In addition, the calculated obstacle edge positions allow the IGV to recognize complex obstacle arrangements and to slow down accordingly. A radial path optimization function calculates the best radial path between the left and right most radii and is sent to motion control for speed determination. Overall, the RPH algorithm allows the IGV to autonomously travel at average speeds of 3mph while avoiding all obstacles, with a processing time of approximately 10ms.

Osseointegrated silicone finger prosthesis using dental implants: a renovated technique.

Science.gov (United States)

Vinnakota, Dileep Nag; Sankar, V Vijay; Chirumamilla, Naveen; Reddy, V Vamsikrishna

2014-11-01

In clinical practice, we come across patients with traumatically amputated or congenitally missing partial or complete fingers that can be restored using microsurgical replantation or transplantation procedures. However, in some cases this might not be possible due to systemic or local factors and the lost or missing part has to be replaced prosthetically to offer psychological and functional wellbeing. These prostheses can be constructed with various materials like acrylics or silicone retained with the help of auxiliary aids. However, these prostheses cause some hindrance in performing functions like writing, typing, etc. The aim of the present trial was to ameliorate the existing design of implant supported finger prosthesis. Distal phalange of middle finger replaced with implant supported silicone finger prosthesis is modified by utilizing a metal framework to support silicone material to improve rigidity while working. We could achieve a good function, esthetics and tactile sensibility with this modified design. Whenever, feasible this design can improve the performance and patients feel a deep sense of satisfaction and improved self-esteem with this modified prosthesis.

Influence of Immobilization Time on Functional Outcome in Radial Neck Fractures in Children.

Science.gov (United States)

Badoi, Adina; Frech-Dörfler, Martina; Häcker, Frank-Martin; Mayr, Johannes

2016-12-01

Background  Radial neck fractures represent 20 to 30% of elbow fractures in children. Incorrect treatment can lead to significant permanent functional impairment. Posttraumatic avascular necrosis may cause a deformity of the radial head and neck. Deformation of the radial head and neck can be more severe after open rather than closed reduction or orthopedic treatment without reduction. The aim of our study was to analyze the influence of immobilization time on functional outcome. Patients and Methods  Retrospective, descriptive study of all children who had been treated for a radial neck fracture between 1999 and 2013 at the University Children's Hospital Basel. Patients were allocated to two groups (group 1: patients treated between 1999 and 2008, group 2: patients treated between 2009 and 2013). The fractures were classified according to the classification of Metaizeau. The primary endpoint was the percentage of patients who reached the full range of elbow motion at the end of the treatment period or the last follow-up. Secondary endpoints were immobilization time and number of patients with persistent physical restrictions of the elbow range of motion as well as the type of restrictions and subjective complaints. Results  A total of 67 patients treated for radial neck fracture were included in the first group (1999-2008). A total of 47 patients were allocated to the second group (2009-2013). Overall, 59 patients in group 1 and 39 patients in group 2 were treated nonoperatively. Average immobilization time was 22.7 days (range, 6-60 days) in group 1 and 13.2 days (range, 0-27 days) in group 2. Full range of motion was observed in 50 to 72.7% of patients in group 1 and in 71.4 to 92% of patients in group 2, depending on the grade of fracture displacement. Overall, 21 patients (31%) of group 1 showed a persistent functional restriction. In group 2, only six patients (12%) suffered from a persistent functional restriction of the elbow range of motion

Malignant esophageal stenosis: treatment with the Wallsten ''TM prosthesis

International Nuclear Information System (INIS)

Paul, L.; Pinto, I.

1998-01-01

To discuss the technical aspects and adders the clinical results of treatment of malignant esophaged dysphagia by placement of a Wallstent prosthesis under fluoroscopic guidance. Over the past six years, we have implanted 63 Wallstent metallic prostheses in 40 patients with un operable malignant dysphagia of esophaged origin. The consisted of 36 men and 6 women with a mean age of 72 years. Seven of the neoplasms were associated with fistula.Six involved recurrent tumors at the point of the surgical anastomosis. Following implantation, the patients were evaluated clinically and radiologically at postoperative hour 48 and periodically thereafter until their death or until the study was completed in September 1996. The placement of the prostheses was achieved in all the patients. Immediate technical problems (malposition or failure to expand) in 27.5% of cases. Forty percent of the patients complained of plain, and there was one death due to massive hematemesis. A clear improvement in dysphagia was obtained was obtained in 79% of and only one of the 7 fistulas was closed. During follow-up, the main complication was obstruction of prosthesis (25%) as a result of tumor overgrowth (9 episodes in 8 patients) or due to food impaction (4 episodes in 3 patients). The rate of retreatment was 27.5%. The mean survival time after prosthesis implantation was 132 ±207 days and 62.5% of the devices were still permeable when the patient died. Implantation of Wallstent prosthesis in cases of malignant esophageal stenosis is easy and safe, and constitutes an effective treatment of dysphagia. Nevertheless, thorough knowledge of the technical aspects ensures better results and the strict assessment of the indications guarantees an improved cost-benefit ratio for this technique. (Author) 23 refs

Iris reconstruction using artificial iris prosthesis for management of aniridia.

Science.gov (United States)

Mostafa, Yehia S; Osman, Amr A; Hassanein, Dina H; Zeid, Ashraf M; Sherif, Ahmed M

2018-01-01

To discuss the limitations and benefits of the BrightOcular prosthetic artificial iris device in management of aniridia associated with aphakia or cataract. This is a retrospective study including 5 eyes of 4 patients who underwent implantation of the BrightOcular iris prosthesis (Stellar Devices) for total or partial aniridia. The cases included 2 eyes of 1 patient with congenital aniridia associated with congenital cataract and 3 eyes with traumatic aniridia: 1 with subluxated cataractous lens and 2 with aphakia. In all cases, the iris prosthesis was implanted after a 3-piece acrylic intraocular lens was implanted. We evaluated the clinical course with a minimum follow-up period of 6 months, the intraoperative and postoperative complications, and the cosmetic satisfaction of patients. All patients had improved uncorrected distance visual acuity and best-corrected distance visual acuity. All patients had a transient corneal edema that resolved within the first postoperative week. Only the patient with congenital aniridia had a permanent increase in intraocular pressure and developed a band keratopathy throughout a 2-year follow-up period. The prosthesis was well-centered in all eyes except for one case that required scleral suture fixation after 3 months. All patients had a satisfactory cosmetic appearance. BrightOcular iris prosthesis is a safe and useful tool to correct aniridia associated with pseudophakia or aphakia. Being foldable, it is easy to be implanted through a small incision and placed in the ciliary sulcus without sutures when properly sized. Cosmetic results are satisfactory. Sizing methods should be improved.

Early postoperative dislocation of the anterior Maverick lumbar disc prosthesis: report of 2 cases.

Science.gov (United States)

Gragnaniello, Cristian; Seex, Kevin A; Eisermann, Lukas G; Claydon, Matthew H; Malham, Gregory M

2013-08-01

The authors report on 2 cases of anterior dislocation of the Maverick lumbar disc prosthesis, both occurring in the early postoperative period. These cases developed after experience with more than 50 uneventful cases and were therefore thought to be unrelated to the surgeon's learning curve. No similar complications have been previously reported. The anterior Maverick device has a ball-and-socket design made of cobalt-chromium-molybdenum metal plates covered with hydroxyapatite. The superior and inferior endplates have keels to resist translation forces. The patient in Case 1 was a 52-year-old man with severe L4-5 discogenic pain; and in Case 2, a 42-year-old woman with disabling L4-5 and L5-S1 discogenic back pain. Both patients were without medical comorbidities and were nonsmokers with no risk factors for osteoporosis. Both had undergone uneventful retroperitoneal approaches performed by a vascular access surgeon. Computed tomography studies on postoperative Day 2 confirmed excellent prosthesis placement. Initial recoveries were uneventful. Two weeks postoperatively, after stretching (extension or hyperextension) in bed at home, each patient suffered the sudden onset of severe abdominal pain with anterior dislocation of the Maverick prosthesis. The patients were returned to the operating room and underwent surgery performed by the same spinal and vascular surgeons. Removal of the Maverick prosthesis and anterior interbody fusion with a separate cage and plate were performed. Both patients had recovered well with good clinical and radiological recovery at the 6- and 12-month follow-ups. Possible causes of the anterior dislocation of the Maverick prosthesis include the following: 1) surgeon error: In both cases the keel cuts were neat, and early postoperative CT confirmed good placement of the prosthesis; 2) equipment problem: The keel cuts may have been too large because the cutters were worn, which led to an inadequate press fit of the implants; 3) prosthesis

Case Report: Magnetically retained silicone facial prosthesis ...

African Journals Online (AJOL)

Prosthetic camouflaging of facial defects and use of silicone maxillofacial material are the alternatives to the surgical retreatment. Silicone elastomers provide more options to clinician for customization of the facial prosthesis which is simple, esthetically good when coupled with bio magnets for retention. Key words: Magnet ...

Fusion around cervical disc prosthesis: case report.

NARCIS (Netherlands)

Bartels, R.H.M.A.; Donk, R.

2005-01-01

OBJECTIVE AND IMPORTANCE: Cervical arthroplasty is a relatively new method to maintain motion after cervical anterior discectomy. Two cases are presented in which bony fusion occurred around a cervical disc prosthesis. CLINICAL PRESENTATION: A 30-year-old man and a 49-year-old woman underwent a

Heterotopic ossification associated with myelopathy following cervical disc prosthesis implantation.

Science.gov (United States)

Wenger, Markus; Markwalder, Thomas-Marc

2016-04-01

This case report presents a 37-year-old man with clinical signs of myelopathy almost 9 years after implantation of a Bryan disc prosthesis (Medtronic Sofamor Danek, Memphis, TN, USA) for C5/C6 soft disc herniation. As demonstrated on MRI and CT scan, spinal cord compression was caused by bony spurs due to heterotopic ossification posterior to the still moving prosthesis. The device, as well as the ectopic bone deposits, had to be removed because of myelopathy and its imminent aggravation. Conversion to anterior spondylodesis was performed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Short-Term Effect of Prosthesis Transforming Sensory Modalities on Walking in Stroke Patients with Hemiparesis

Science.gov (United States)

Sekiguchi, Yusuke; Honda, Keita; Ishiguro, Akio

2016-01-01

Sensory impairments caused by neurological or physical disorders hamper kinesthesia, making rehabilitation difficult. In order to overcome this problem, we proposed and developed a novel biofeedback prosthesis called Auditory Foot for transforming sensory modalities, in which the sensor prosthesis transforms plantar sensations to auditory feedback signals. This study investigated the short-term effect of the auditory feedback prosthesis on walking in stroke patients with hemiparesis. To evaluate the effect, we compared four conditions of auditory feedback from plantar sensors at the heel and fifth metatarsal. We found significant differences in the maximum hip extension angle and ankle plantar flexor moment on the affected side during the stance phase, between conditions with and without auditory feedback signals. These results indicate that our sensory prosthesis could enhance walking performance in stroke patients with hemiparesis, resulting in effective short-term rehabilitation. PMID:27547456

A kinematic assessment of knee prosthesis from fluoroscopy images

International Nuclear Information System (INIS)

Hossain, Mohammad Abrar; Fukunaga, Michihiko; Hirokawa, Shunji

2008-01-01

We have developed a technique for estimation 3D motion of knee prosthesis from its 2D perspective projections. Our estimation algorithm includes some innovations such as a two-step estimation algorithm, incorporative use of a geometric articulation model and a new method to solve two silhouettes' overlapping problem. Computer model simulations and experiments results demonstrated that our algorithms give sufficient accuracy. Next, with the cooperation of medical surgeons, we assessed the algorithm's clinical performance by applying it to moving fluoroscopy images of patients who had just undergone total knee arthroplasty (TKA) recently. Our experiments were done in four steps; first we have taken the moving X-ray pictures called fluoroscopy images of the knee prosthesis at different knee motions; second, introduced the absolute positions/orientations for both components, third, introduced the relative positions/orientations between the femoral and the tibial components and finally, introduced the contact points trajectories between the femur and the tibial insert. We drew the estimation results graphically and made the computer-aided detection (CAD) model pictures of the prosthesis, thereby helping us to assess how the relative motions between the femoral and the tibial components were generated. Estimation results of the clinical applications demonstrated that our algorithm worked well as like as theoretical. (author)

A new prosthetic alignment device to read and record prosthesis alignment data.

Science.gov (United States)

Pirouzi, Gholamhossein; Abu Osman, Noor Azuan; Ali, Sadeeq; Davoodi Makinejad, Majid

2017-12-01

Prosthetic alignment is an essential process to rehabilitate patients with amputations. This study presents, for the first time, an invented device to read and record prosthesis alignment data. The digital device consists of seven main parts: the trigger, internal shaft, shell, sensor adjustment button, digital display, sliding shell, and tip. The alignment data were read and recorded by the user or a computer to replicate prosthesis adjustment for future use or examine the sequence of changes in alignment and its effect on the posture of the patient. Alignment data were recorded at the anterior/posterior and medial/lateral positions for five patients. Results show the high level of confidence to record alignment data and replicate adjustments. Therefore, the device helps patients readjust their prosthesis by themselves, or prosthetists to perform adjustment for patients and analyze the effects of malalignment.

Endoscopic palliation of esophageal and cardial cancer: Nd:YAG laser and prosthesis

Science.gov (United States)

Norberto, Lorenzo; Ranzato, Riccardo; Marino, Saverio; Angriman, Imerio; Vella, Vincenzo; Donadi, Michele; D'Amico, D. F.

1997-12-01

From November 1, 1992 to January 31, 1997, 227 patients with inoperable esophageal and cardial carcinomas were treated with Nd:YAG laser therapy and prosthesis intubation. The retrograde technique was used in most cases. The tumor involved in 75 pts the Cardia, in 65 the middle thoracic esophagus, in 47 pts the lower thoracic esophagus, in 23 in the upper thoracic esophagus and in 17 in the cervical esophagus. The indications for palliative Nd:YAG laser and prosthesis intubation were a locally advanced or metastatic tumor in 146 pts (64.4%) and poor surgical risk in 81 pts (35.6%). The quality of palliation was evaluated according to the ability to swallow. The mean survival rate of the patients during the follow up was 22 weeks for the laser therapy and 16 weeks for the prosthesis intubation.

The influence of prosthesis diameter in stapes surgery: a meta-analysis and systematic review of the literature.

Science.gov (United States)

Laske, Roman D; Röösli, Christof; Chatzimichalis, Michail Vasileios; Sim, Jae Hoon; Huber, Alexander M

2011-06-01

To analyze the influence of stapes prosthesis diameter on postoperative hearing results after stapedotomy without interposition in otosclerotic patients. PubMed search from 1970 to 2009 using the key words stapedotomy or stapedectomy or otosclerosis or stapesplasty. Inclusion criteria to select articles and patient groups for meta-analysis and statistical analyses were as follows: otosclerosis as diagnosis, clear description of technique and prosthesis size, calibrated stapedotomy, and complete report of functional results. Five controlled studies were found analyzing the influence of prosthesis diameter and reporting the results in a comparable way for meta-analysis (n = 590). Sixty-two studies not analyzing the influence of prosthesis diameter contained comparable subgroups with a total of 9,536 cases. These cases were pooled according to their diameter (0.3, 0.4, 0.5, 0.6,and 0.8 mm). The results of air conduction, bone conduction, air-bone gap (ABG), and success rate (closure of the ABG within 10 dB as percentage of the total cases) for all groups and frequency-specific ABG results were gathered. Furthermore, 12 clinical and experimental studies were reviewed that did not contribute to the statistical analysis. A meta-analysis performed for success rate of the 5 controlled studies showed favorable results for 0.6-mm over 0.4-mm prostheses (success rate, 67% versus 58%, p = 0.05). In the statistical analysis of the pooled data, the 0.6-mm prosthesis showed better results compared with 0.4 mm (p prosthesis in the high frequencies. There was no difference in postoperative change of bone conduction in the 0.6- and 0.4-mm groups. Statistically significant results could not be assessed for other prosthesis diameters because of the small number of cases reported. A 0.6-mm diameter piston prosthesis is associated with significantly better results than a 0.4-mm prosthesis and should be used if the surgical conditions allow it.

Seismic Linear Noise Attenuation with Use of Radial Transform

Science.gov (United States)

Szymańska-Małysa, Żaneta

2018-03-01

One of the goals of seismic data processing is to attenuate the recorded noise in order to enable correct interpretation of the image. Radial transform has been used as a very effective tool in the attenuation of various types of linear noise, both numerical and real (such as ground roll, direct waves, head waves, guided waves etc). The result of transformation from offset - time (X - T) domain into apparent velocity - time (R - T) domain is frequency separation between reflections and linear events. In this article synthetic and real seismic shot gathers were examined. One example was targeted at far offset area of dataset where reflections and noise had similar apparent velocities and frequency bands. Another example was a result of elastic modelling where linear artefacts were produced. Bandpass filtering and scaling operation executed in radial domain attenuated all discussed types of linear noise very effectively. After noise reduction all further processing steps reveal better results, especially velocity analysis, migration and stacking. In all presented cases signal-to-noise ratio was significantly increased and reflections covered previously by noise were revealed. Power spectra of filtered seismic records preserved real dynamics of reflections.

Phantom studies of triple photon absorptiometry and bone mineral measurement at a hip prosthesis

International Nuclear Information System (INIS)

Farrell, T.J.; Webber, C.E.

1992-01-01

The feasibility of using triple photon absorptiometry (TPA) for the measurement of bone mineral mass about a hip prosthesis was examined. A theoretical expression describing the variance of TPA measurements was verified using a triple photon source and phantom materials which simulate the soft tissue-bone mineral-metal prosthesis system. The expression for the variance was used to determine an optimized set of photon energies. It was shown that a precision of 3% could be obtained for reasonable measurement times using this optimized set of energies and that TPA should be a feasible approach for measurement of bone mineral about a hip prosthesis. (orig.)

21 CFR 888.3360 - Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) metallic cemented or... Hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metallic cemented or uncemented prosthesis is a device intended to be implanted...

[COMPUTER ASSISTED DESIGN AND ELECTRON BEAMMELTING RAPID PROTOTYPING METAL THREE-DIMENSIONAL PRINTING TECHNOLOGY FOR PREPARATION OF INDIVIDUALIZED FEMORAL PROSTHESIS].

Science.gov (United States)

Liu, Hongwei; Weng, Yiping; Zhang, Yunkun; Xu, Nanwei; Tong, Jing; Wang, Caimei

2015-09-01

To study the feasibility of preparation of the individualized femoral prosthesis through computer assisted design and electron beammelting rapid prototyping (EBM-RP) metal three-dimensional (3D) printing technology. One adult male left femur specimen was used for scanning with 64-slice spiral CT; tomographic image data were imported into Mimics15.0 software to reconstruct femoral 3D model, then the 3D model of individualized femoral prosthesis was designed through UG8.0 software. Finally the 3D model data were imported into EBM-RP metal 3D printer to print the individualized sleeve. According to the 3D model of individualized prosthesis, customized sleeve was successfully prepared through the EBM-RP metal 3D printing technology, assembled with the standard handle component of SR modular femoral prosthesis to make the individualized femoral prosthesis. Customized femoral prosthesis accurately matching with metaphyseal cavity can be designed through the thin slice CT scanning and computer assisted design technology. Titanium alloy personalized prosthesis with complex 3D shape, pore surface, and good matching with metaphyseal cavity can be manufactured by the technology of EBM-RP metal 3D printing, and the technology has convenient, rapid, and accurate advantages.

Novel use of an air-filled breast prosthesis to allow radiotherapy to recurrent colonic cancer.

LENUS (Irish Health Repository)

O'Duffy, F

2012-02-01

AiM: The authors present the novel and successful use of an air-filled breast prosthesis for extra pelvic exclusion of small bowel to facilitate adjuvant radiotherapy following resection of recurrent adenocarcinoma of the ascending bowel. The therapeutic use of radiotherapy in colon cancer can cause acute or chronic radiation enteropathy. Mobile small bowel can be sequestered in \\'dead space\\' or by adhesions exposing it to adjuvant radiotherapy. A variety of pelvic partitioning methods have been described to exclude bowel from radiation fields using both native and prosthetic materials. METHOD: In this case a 68 year old presented with ascending colon adenocarcinoma invading the peritoneum and underwent en bloc peritoneal resection. Thirty-seven months later surveillance CT identified a local recurrence. Subsequent resection resulted in a large iliacus muscle defect which would sequester small bowel loops thus exposing the patient to radiation enteropathy. The lateral position of the defect precluded the use of traditional pelvic partitioning methods which would be unlikely to remain in place long enough to allow radiotherapy. A lightweight air-filled breast prosthesis (Allergan 133 FV 750 cms) secured in place with an omentoplasty was used to fill the defect. RESULTS: Following well tolerated radiotherapy the prosthesis was deflated under ultrasound guidance and removed via a 7-cm transverse incision above the right iliac crest. The patient is disease free 18 months later with no evidence of treatment related morbidity. CONCLUSION: The use of a malleable air-filled prosthesis for pelvic partitioning allows specific tailoring of the prosthesis size and shape for individual patient defects. It is also lightweight enough to be secured in place using an omentoplasty to prevent movement related prosthesis migration. In the absence of adequate omentum a mesh sling may be considered to allow fixation. In this case the anatomy of the prosthesis position allowed for its

Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

National Research Council Canada - National Science Library

Humayun, M

2001-01-01

An electronic retinal prosthesis is under development to treat retinitis pigmentosa and age-related macular degeneration, two presently incurable diseases of the outer retina that afflict millions world-wide...

Biomedical and psychosocial factors influencing transtibial prosthesis fit : a Delphi survey among health care professionals

NARCIS (Netherlands)

Baars, Erwin C.; Schrier, Ernst; Geertzen, Jan H.; Dijkstra, Pieter U.

2015-01-01

Purpose: We aimed to reach consensus among professionals caring for prosthesis users, on definitions of biomedical and psychosocial factors, to assess their influence on fit of transtibial prosthesis and to identify new factors. Method: A three-round, internet-based, Delphi survey was conducted

An innovative and simple approach to fabricate a hollow ocular prosthesis with functional lubricant reservoir: A solution to artificial eye comfort

Directory of Open Access Journals (Sweden)

Aditya Anil Kavlekar

2017-01-01

Full Text Available The loss of an eye is an emotional and psychological setback to the patient. An ocular prosthesis is created to restore the lost anatomical structure and to correct the cosmetic defect. The tear reflexes do not function at optimal levels in anophthalmic sockets which make prosthesis wear uncomfortable. This case report presents an innovative hollow ocular prosthesis with functional lubricant reservoir which upon normal blinking would draw the lubricant from the reservoir through an exit hole which spreads over the prosthesis allowing a comfortable and long duration of prosthesis wear.

Heterotopic ossification of the elbow after closed reduction and retrograde intramedullary nailing for radial neck fracture treated by anconeus interposition.

Science.gov (United States)

Sreenivas, T; Menon, Jagdish; Nataraj, A R

2013-12-01

Heterotopic ossification around the elbow can lead to considerable functional disability. We describe a case of a 42-year-old man who developed heterotopic ossification of his elbow after closed reduction of the elbow dislocation and radial neck fracture and retrograde intramedullary nailing for radial neck fracture. During the follow-up after initial surgery, movements of the elbow were gradually deteriorated and diagnosed as heterotopic ossification of the elbow. Implant removal, radial head excision along with heterotopic mass, and also interposition of the anconeus muscle resulted in improvement of his elbow mobility. At 18 months of follow-up, patient had elbow flexion arc of 15°-110°, 70° of supination, and 50° of pronation without recurrence of heterotopic ossification. The uniqueness of this case lies in the treatment of heterotopic ossification of the elbow to prevent its recurrence, which was developed after retrograde intramedullary nailing for radial neck fracture following closed reduction.

Ipsilateral Fracture Shaft Femur with Neglected Dislocation of Prosthesis: A Case Report

Directory of Open Access Journals (Sweden)

Mantu Jain

2013-10-01

Full Text Available Introduction: Neglected hip dislocation is rare in today’s world and after prosthesis replacement even rarer finding. However such patients may not report to surgeons until they develop secondary complications. Management of such patient’s is a challenge to the treating surgeon and need to be tailored suiting to patient’s demands, expectations and constraints of financial resources. We did not find a similar case in the electronic and print media and therefore report this case which was innovatively managed. Case Report: A 60 year farmer presented with fracture shaft femur and ipsilateral dislocation prosthesis of right hip. He had a hemiarthroplasty done for fracture neck of femur in the past but used to walk with a lurch since he started to ambulate after discharge. However he was satisfied despite “some problems” which had caused shortening of his limb. The patient was informed of the various treatment options and their possible complications. He expressed his inability to afford a Total Hip Arthroplasty (THA at any stage and consented for other options discussed with him. The patient was positioned supine and adductor tenotomy done. Next he was positioned laterally and the fracture was fixed with heavy duty broad dynamic compression plate and screws. The wound was temporarily closed. Now through the previous scar via posterior approach the hip was exposed. The prosthesis was found to be firmly fixed to the proximal femur. The acetabulum was cleared with fibrous tissue. All attempts the prosthesis to relocate the prosthesis failed after several attempts and it was best decided to leave alone. Post operatively period was uneventful. At follow up he refused for any further manoeuvre in future inform of heavy traction and attempts to reduce the same. At one year when he was walking unaided and his X-rays showed that fracture had well united his SF-36 score was PCS – 49.6 and MCS – 51.9. Conclusion: Ipsilateral shaft femur fracture

Plasma distributions in meteor head echoes and implications for radar cross section interpretation

Science.gov (United States)

Marshall, Robert A.; Brown, Peter; Close, Sigrid

2017-09-01

The derivation of meteoroid masses from radar measurements requires conversion of the measured radar cross section (RCS) to meteoroid mass. Typically, this conversion passes first through an estimate of the meteor plasma density derived from the RCS. However, the conversion from RCS to meteor plasma density requires assumptions on the radial electron density distribution. We use simultaneous triple-frequency measurements of the RCS for 63 large meteor head echoes to derive estimates of the meteor plasma size and density using five different possible radial electron density distributions. By fitting these distributions to the observed meteor RCS values and estimating the goodness-of-fit, we determine that the best fit to the data is a 1 /r2 plasma distribution, i.e. the electron density decays as 1 /r2 from the center of the meteor plasma. Next, we use the derived plasma distributions to estimate the electron line density q for each meteor using each of the five distributions. We show that depending on the choice of distribution, the line density can vary by a factor of three or more. We thus argue that a best estimate for the radial plasma distribution in a meteor head echo is necessary in order to have any confidence in derived meteoroid masses.

Bicentric bipolar hip prosthesis: A radiological study of movement at the interprosthetic joint

Directory of Open Access Journals (Sweden)

Anil Kumar Rai

2011-01-01

Full Text Available Background: The bipolar hip prostheses after some time functions as a unipolar device. There is a need to change the design of bipolar hip prostheses to make it function as a bipolar device over a prolonged period of time. A bicentric bipolar hip prosthesis was used as an implant for various conditions of the hip. We evaluated the movement of this newly developed prosthesis at the interprosthetic joint radiologically at periodic intervals. Materials and Methods: Fifty two cases were operarted with the Bicentric bipolar prosthesis for indications like fracture neck of femur and various other diseases of the hip and were followed up with serial radiographs at periodic intervals to evaluate, what fraction of the total abduction at the hip was occurring at the interprosthetic joint. Results: In cases of intracapsular fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 33.74% (mean value of all the patients, which fell to 25.66% at 1.5 years. In indications for bipolar hemireplacement other than fracture neck of femur, the percentage of total abduction occurring at the interprosthetic joint at 3 months follow-up was 71.71% (mean value and at 1.5 years it was 67.52%. Conclusion: This study shows the relative preservation of inner bearing movement in the bipolar hip prosthesis with time probably due its refined design. Further refinements are needed to make the prosthesis work better in patients of intracapsular fracture neck femur.

Evidence of echoic memory with a multichannel cochlear prosthesis.

Science.gov (United States)

Jerger, S; Watkins, M J

1988-10-01

Short-term memory was examined in a subject with a multichannel cochlear prosthesis. Serial recall for lists of digits revealed what are widely regarded as the principal hallmarks of echoic memory, namely the recency effect and the suffix effect. Thus, probability of recall increased for the last one or two digits, except when a nominally irrelevant but spoken item was appended to the to-be-remembered list. It appears, therefore, that a multichannel cochlear implant can give rise to not only the perception of, but also an echoic memory for, speech. As with normal subjects, the suffix effect did not occur with a nonspeech suffix, implying that the echoic memory from the prosthesis shows normal sensitivity to the distinction between speech and nonspeech.

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease

NARCIS (Netherlands)

van Slooten, Ymkje J.; Melle, van Joost P.; Freling, Hendrik G.; Bouma, Berto J.; van Dijk, Arie P. J.; Jongbloed, Monique R. M.; Post, Martijn C.; Sieswerda, Gertjan T.; in 't Veld, Anna Huis; Ebels, Tjark; Voors, Adriaan A.; Pieper, Petronella G.

Objectives To report the prevalence of aortic valve prosthesis patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease

NARCIS (Netherlands)

van Slooten, Ymkje J.; van Melle, Joost P.; Freling, Hendrik G.; Bouma, Berto J.; van Dijk, Arie Pj; Jongbloed, Monique Rm; Post, Martijn C.; Sieswerda, Gertjan T.; Huis In 't Veld, Anna; Ebels, Tjark; Voors, Adriaan A.; Pieper, Petronella G.

2016-01-01

To report the prevalence of aortic valve prosthesis-patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis later in

Prosthetic replacement of the medial meniscus in cadaveric knees - Does the prosthesis mimic the functional behavior of the native meniscus?

NARCIS (Netherlands)

Tienen, TG; Verdonschot, N; Heijkants, RGJC; Buma, R; Scholten, JGF; van Kampen, A; Veth, RPH

2004-01-01

Meniscus replacement by a polymer meniscus prosthesis in dogs resulted in generation of new meniscal tissue. Hypothesis: Optimal functioning of the prosthesis would involve realistic deformation and motion patterns of the prosthesis during knee joint motion. Study Design: Controlled laboratory

Investigation of the in-vitro loading on an artificial spinal disk prosthesis

Energy Technology Data Exchange (ETDEWEB)

Kyriacou, P A; Pancholi, M P [School of Engineering and Mathematical Sciences, City University London (United Kingdom); Yeh, J, E-mail: P.Kyriacou@city.ac.u [Department of Neurosurgery, Royal London Hospital, Barts and the London NHS Trust, London (United Kingdom)

2009-07-01

Spinal diseases imposes considerable burden to both patients and society. In recent years, much surgical efforts have been made in advancing the treatment of neck and back pain. Of particular prominence is the increasing clinical acceptance and use of intervertebral artificial disk prosthesis for the treatment of discogenic back pain. Despite this increased use of such disks, their in-vivo monitoring remains rudimentary. In an effort to develop an intelligent artificial spinal disk where the in-vivo loading of the spine can by studied for the first time an experimental set up has been created in order to initially study the in-vitro loading on an artificial disc prosthesis. Eight strain gauges and two piezoresistive sensors were used and placed suitably in the artificial disk prosthesis. The results from the in-vitro loading showed linear relationship between loading and the outputs from the sensors with good repeatability and less hysteresis.

Investigation of the in-vitro loading on an artificial spinal disk prosthesis

International Nuclear Information System (INIS)

Kyriacou, P A; Pancholi, M P; Yeh, J

2009-01-01

Spinal diseases imposes considerable burden to both patients and society. In recent years, much surgical efforts have been made in advancing the treatment of neck and back pain. Of particular prominence is the increasing clinical acceptance and use of intervertebral artificial disk prosthesis for the treatment of discogenic back pain. Despite this increased use of such disks, their in-vivo monitoring remains rudimentary. In an effort to develop an intelligent artificial spinal disk where the in-vivo loading of the spine can by studied for the first time an experimental set up has been created in order to initially study the in-vitro loading on an artificial disc prosthesis. Eight strain gauges and two piezoresistive sensors were used and placed suitably in the artificial disk prosthesis. The results from the in-vitro loading showed linear relationship between loading and the outputs from the sensors with good repeatability and less hysteresis.

Design and Control of a New Biomimetic Transfemoral Knee Prosthesis Using an Echo-Control Scheme

Directory of Open Access Journals (Sweden)

Mario G. Bernal-Torres

2018-01-01

Full Text Available Passive knee prostheses require a significant amount of additional metabolic energy to carry out a gait cycle, therefore affecting the natural human walk performance. Current active knee prostheses are still limited because they do not reply with accuracy of the natural human knee movement, and the time response is relatively large. This paper presents the design and control of a new biomimetic-controlled transfemoral knee prosthesis based on a polycentric-type mechanism. The aim was to develop a knee prosthesis able to provide additional power and to mimic with accuracy of the natural human knee movement using a stable control strategy. The design of the knee mechanism was obtained from the body-guidance kinematics synthesis based on real human walking patterns obtained from computer vision and 3D reconstruction. A biomechanical evaluation of the synthesized prosthesis was then carried out. For the activation and control of the prosthesis, an echo-control strategy was proposed and developed. In this echo-control strategy, the sound side leg is sensed and synchronized with the activation of the knee prosthesis. An experimental prototype was built and evaluated in a test rig. The results revealed that the prosthetic knee is able to mimic the biomechanics of the human knee.

Radial nerve measurements in nonsymptomatic upper extremities of Filipinos: A cross-sectional study.

Science.gov (United States)

Gonzalez-Suarez, Consuelo B; Dones, Valentin C; Grimmer, Karen; Thoirs, Kerry; Milanese, Steven; Atlas, Alvin

2015-10-01

Despite reports on the association of radial nerve (RN) size and lateral epicondylalgia (LE), Filipino normative values on RN size in healthy elbows are not established. An association with upper extremity anthropometric measurements is likewise not reported. Musculoskeletal ultrasound measurements of the RN at the level of the lateral epicondyle (RN-LE), posterior interosseous nerve at the level of the radial head and supinator (PIN-RH and PIN-sup), and superficial RN (SRN) in the elbows of healthy Filipinos were made in Manila from January-September 2011. A total of 198 elbows of 99 healthy participants aged 43 years (range, 33-48 years) [median(IQR)] were investigated. Men have larger PIN-RH, PIN-sup, and SRN compared with women. Arm length was associated with PIN-RH, PIN-sup, and SRN (P values can now be used for comparison in elbows with LE. © 2015 Wiley Periodicals, Inc.

New protocol for construction of eyeglasses-supported provisional nasal prosthesis using CAD/CAM techniques.

Science.gov (United States)

Ciocca, Leonardo; Fantini, Massimiliano; De Crescenzio, Francesca; Persiani, Franco; Scotti, Roberto

2010-01-01

A new protocol for making an immediate provisional eyeglasses-supported nasal prosthesis is presented that uses laser scanning, computer-aided design/computer-aided manufacturing procedures, and rapid prototyping techniques, reducing time and costs while increasing the quality of the final product. With this protocol, the eyeglasses were digitized, and the relative position of the nasal prosthesis was planned and evaluated in a virtual environment without any try-in appointment. This innovative method saves time, reduces costs, and restores the patient's aesthetic appearance after a disfiguration caused by ablation of the nasal pyramid better than conventional restoration methods. Moreover, the digital model of the designed nasal epithesis can be used to develop a definitive prosthesis anchored to osseointegrated craniofacial implants.

Perivalvular pannus and valve thrombosis: two concurrent mechanisms of mechanical valve prosthesis dysfunction.

Science.gov (United States)

Arnáiz-García, María Elena; González-Santos, Jose María; Bueno-Codoñer, María E; López-Rodríguez, Javier; Dalmau-Sorlí, María José; Arévalo-Abascal, Adolfo; Arribas-Jiménez, Antonio; Diego-Nieto, Alejandro; Rodríguez-Collado, Javier; Rodríguez-López, Jose María

2015-02-01

A 78-year-old woman was admitted to our institution with progressive dyspnea. She had previously been diagnosed with rheumatic heart disease and had undergone cardiac surgery for mechanical mitral valve replacement ten years previously. Transesophageal echocardiography revealed blockage of the mechanical prosthesis and the patient was scheduled for surgery, in which a thrombus was removed from the left atrial appendage. A partial thrombosis of the mechanical prosthesis and circumferential pannus overgrowth were concomitantly detected. Prosthetic heart valve blockage is a rare but life-threatening complication, the main causes of which are thrombosis and pannus formation. The two conditions are different but both are usually misdiagnosed. Two concurrent mechanisms of prosthesis blockage were found in this patient. Copyright © 2014 Sociedade Portuguesa de Cardiologia. Published by Elsevier España. All rights reserved.

Complications and Clinical Considerations of the Implant-Retained Zirconia Complete-Arch Prosthesis with Various Opposing Dentitions.

Science.gov (United States)

Gonzalez, Jorge; Triplett, Robert G

To evaluate the performance of the implant-retained zirconia complete-arch prosthesis with various opposing dentitions. The 40 patients included in this retrospective case series study were treated with one or two implant-retained zirconia complete-arch prostheses (ZIRCAP) using the Zirkonzahn protocol. Prettau zirconia frames were created with strategic cutbacks in the structure to extend zirconia incisal coverage of the esthetic anterior sextants and complete monolithic zirconia in the molar areas; subsequent layers of porcelain were applied to nonfunctional and esthetic areas. Patients had three possible occlusal scenarios: (1) maxillary ZIRCAP and mandibular ZIRCAP, (2) maxillary ZIRCAP and mandibular natural dentition, and (3) maxillary ZIRCAP and mandibular conventional hybrid prosthesis. Complications were recorded during follow-up appointments 3, 6, and 12 months after definitive prosthesis delivery. The mean treatment observation period was 33 months. Eight prosthetic complications were noted for the 40 implant-retained zirconia complete-arch prostheses (18.18%), including six cases of minor porcelain chipping and two cases of debonding of the metal insert from the zirconia framework. Maxillary ZIRCAP opposing mandibular ZIRCAP and maxillary ZIRCAP opposing mandibular natural dentition occlusal scenarios presented the same complication ratio of 4. No complications were seen in the maxillary ZIRCAP opposing mandibular conventional hybrid prosthesis group, yet 16 complications were found as denture tooth fractures in 12 mandibular conventional hybrid prostheses (ratio of 0.75). The results indicate that the implant-retained zirconia complete-arch prosthesis offers acceptable performance for use as an alternative to the conventional titanium framework acrylic veneer prosthesis for complete edentulism with a lower incidence of prosthetic complications and fewer maintenance appointments. Chipping of veneering porcelain was the most common complication, but a

Prosthesis-patient mismatch

Directory of Open Access Journals (Sweden)

Philippe Pibarot

2011-04-01

Full Text Available Prosthesis-patient mismatch (PPM is present when the effective orifice area of the inserted prosthetic valve is too small in relation to body size. Its main hemodynamic consequence is to generate higher than expected gradients through normally functioning prosthetic valves. The purpose of this review is to present an update on the present state of knowledge with regards to diagnosis, prognosis and prevention of PPM. PPM is a frequent occurrence (20%–70% of aortic valve replacements that has been shown to be associated with worse hemodynamics, less regression of left ventricular hypertrophy, more cardiac events, and lower survival. Moreover, as opposed to most other risk factors, PPM can largely be prevented by using a prospective strategy at the time of operation.

Bioelectronic retinal prosthesis

Science.gov (United States)

Weiland, James D.

2016-05-01

Retinal prosthesis have been translated to clinical use over the past two decades. Currently, two devices have regulatory approval for the treatment of retinitis pigmentosa and one device is in clinical trials for treatment of age-related macular degeneration. These devices provide partial sight restoration and patients use this improved vision in their everyday lives to navigate and to detect large objects. However, significant vision restoration will require both better technology and improved understanding of the interaction between electrical stimulation and the retina. In particular, current retinal prostheses do not provide peripheral visions due to technical and surgical limitations, thus limiting the effectiveness of the treatment. This paper reviews recent results from human implant patients and presents technical approaches for peripheral vision.

Total hip arthroplasty survival in femoral head avascular necrosis versus primary hip osteoarthritis: Case-control study with a mean 10-year follow-up after anatomical cementless metal-on-metal 28-mm replacement.

Science.gov (United States)

Ancelin, D; Reina, N; Cavaignac, E; Delclaux, S; Chiron, P

2016-12-01

Total hip arthroplasty is the most widely used procedure to treat avascular necrosis (AVN) of the femoral head. Few studies have compared the outcomes of THA in femoral head AVN and primary hip osteoarthritis. Therefore we performed a case-control study to compare THA for femoral head AVN vs. primary hip osteoarthritis in terms of: (1) prosthesis survival, (2) complication rates, (3) functional outcomes and radiographic outcomes, (4) and to determine whether specific risk factors for THA failure exist in femoral head AVN. THA survival is similar in femoral head AVN and primary hip osteoarthritis. We compared two prospective cohorts of patients who underwent THA before 65 years of age, one composed of cases with femoral head AVN and the other of controls with primary hip osteoarthritis. In both cohorts, a cementless metal-on-metal prosthesis with a 28-mm cup and an anatomical stem was used. Exclusion criteria were THA with other types of prosthesis, posttraumatic AVN, and secondary osteoarthritis. With α set at 5%, to obtain 80% power, 246 patients were required in all. Prosthesis survival was assessed based on time to major revision (defined as replacement of at least one implant fixed to bone) and time to aseptic loosening. The other evaluation criteria were complications, Postel-Merle d'Aubigné (PMA) score, and the Engh and Agora Radiographic Assessment (ARA) scores for implant osseointegration. The study included 282 patients, 149 with AVN and 133 with osteoarthritis. Mean age was 47.8±10.2 years (range, 18.5-65) and mean follow-up was 11.4±2.8 years (range, 4.5-18.3 years). The 10-year survival rates were similar in the two groups: for major revision, AVN group, 92.5% (95% confidence interval [95% CI], 90.2-94.8) and osteoarthritis group, 95.3% (95% CI, 92.9-97.7); for aseptic loosening, AVN group, 98.6% (95% CI, 97.6-98.6) and osteoarthritis, 99.2% (95% CI, 98.4-100). The AVN group had higher numbers of revision for any reason (19 vs. 6, P=0.018) and

Numerical analysis of an osseointegrated prosthesis fixation with reduced bone failure risk and periprosthetic bone loss

NARCIS (Netherlands)

Tomaszewski, P. M.; van Diest, M.; Bulstra, S. K.; Verdonschot, N.; Verkerke, G. J.

2012-01-01

Currently available implants for direct attachment of prosthesis to the skeletal system after transfemoral amputation (OPRA system. Integrum AB, Sweden and ISP Endo/Exo prosthesis, ESKA Implants AG, Germany) show many advantages over the conventional socket fixation. However, restraining

Radial Force: An Underestimated Parameter in Oversizing Transcatheter Aortic Valve Replacement Prostheses: In Vitro Analysis with Five Commercialized Valves.

Science.gov (United States)

Egron, Sandrine; Fujita, Buntaro; Gullón, Lucía; Désirée, Pott; Schmitz-Rode, Thomas; Ensminger, Stephan; Steinseifer, Ulrich

2017-09-05

The goal is to inform in depth on transcatheter aortic valve replacement (TAVR) prosthesis mechanical behavior, depending on frame type, design, and size, and how it crucially impacts the oversizing issue in clinical use, and ultimately the procedure outcome. Transcatheter aortic valve replacement is an established therapy for high-risk patients suffering from aortic stenosis, and the indication for TAVR is progressively expanding to intermediate-risk patients. Choosing the optimal oversizing degree is crucial to safely anchor the TAVR valve-which involves limiting the risks for embolism, aortic regurgitation, conductance disturbance, or annulus rupture-and to increase the valve prosthesis performance. The radial force (RF) profiles of five TAVR prostheses were measured in vitro: the CoreValve 23 and 26 (Medtronic, MN), the Acurate neo S (Symetis, Switzerland), and the SAPIEN XT 23 and 26 (Edwards Lifesciences, CA). Measurements were run with the RX Machine equipment (Machine Solutions Inc., AZ), which is used in ISO standard tests for intravascular stents. Test protocols were adapted for TAVR prostheses. With the prostheses RF profiles' results, mechanical behavior differences could be described and discussed in terms of oversizing strategy and clinical impact for all five valves. Besides, crossing the prostheses' RF profiles with their recommended size windows made the assessment of borderline size cases possible and helped analyze the risks when accurate measurement of patient aortic annulus proves difficult. The prostheses' RF profiles bring new support in clinical decision-making for valve type and size in patients.

Towards a Completely Implantable, Light-Sensitive Intraocular Retinal Prosthesis

National Research Council Canada - National Science Library

Humayun, M

2001-01-01

.... Previous studies have established the feasibility of the retinal prosthesis. Short-term tests in blind humans have shown that degenerated retina will respond to light in a way that is consistent with form vision...

[Our experience with the use of Active-C cervical prosthesis].

Science.gov (United States)

Misik, Ferenc; Böösi, Martina; Papp, Zoltán; Padányi, Csaba; Banczerowski, Péter

2016-09-30

The most widely used surgical procedure in the treatment of cervical spine disc hernias have been the anterior cervical discectomy and fusion for decades. The usage of cervical disc prostheses enabled us to preserve the movements of the affected segments, hereby reducing the overexertion of the adjacent vertebrae and discs. Our goal is to follow our patients operated with Active-C prosthesis (which is used in the Institute since 2010) to gather information about the change of their complaints and about the functioning and unwanted negative effects of the prostheses. Question - Is the usage of Active-C prosthesis an efficient procedure? Between 2010 and 2013, performing the survey of neurological conditions and functional X-ray examinations. We measured the complaints of the patients using the Visual Analogue Scale, Neck Disability Index and Cervical Spine Outcomes Questionnaire. The control group consisted of patients who were operated in one segment using the fusion technique. In the study group according to the Neck Disability Index scale after 18 months, seven patients had no complaints, while twelve persons reported mild and the remaining six moderate complaints. In the control group, moderate complaints were present in four patients, while twelve patients reported mild complaints. The other eight persons showed no complaints. According to the results of the Visual Analogue Scale in the group of prosthesis, the degree of referred pain decreased from 8.6 to 1.84 one and a half years after the surgery. A decrease was observable in the case of axial pain too, from 6.6 down to 1.92 (pcervical disc prosthesis can be considered as an efficient procedure, but at the same time the advantages can only be determined in the long run, therefore further following and studies are required.

Functional property of the cardiac valve prosthesis evaluated in vivo by cine-radiography

International Nuclear Information System (INIS)

Murakoshi, Sadaaki

1986-01-01

Functional property of the convexo-concave Bjoerk-Shiley cardiac valve prosthesis implanted in the mitral position of 21 patients was investigated by integrated cine-radiography repeated for a long term after operation. The maximum opening angle of the tilting disc was 58 ± 2 deg, and was not affected by atrial fibrillation nor by tachycardia up to 160 bpm. There was no change in the maximum opening angle of the disc observed during follow-up period. Good correlation between shortning of the disc opening time and increase in pulse rate suggests excellent adaptation of this prosthesis for tachycardia induced by exercise or electric pacing. However, atrial fibrillation causes time delay in disc closure immediately after prolonged R-R interval. Disc rotation alleviating disc wear was observed in all the patients whether it moves slow or quick. Dysfunction of the disc opening can be readily determined not only by measuring the maximum disc opening angle, but also by observing the characteristic movement indicated in this study. It is concluded from these results that clinical apprication for the convexo-concave Bjoerk-Shiley valve prosthesis is appropriate and cine-radiography is an useful non-invasive examination of cardiac valve prosthesis for long follow-up period. (author)

Functional property of the cardiac valve prosthesis evaluated in vivo by cine-radiography

Energy Technology Data Exchange (ETDEWEB)

Murakoshi, Sadaaki

1986-07-01

Functional property of the convexo-concave Bjoerk-Shiley cardiac valve prosthesis implanted in the mitral position of 21 patients was investigated by integrated cine-radiography repeated for a long term after operation. The maximum opening angle of the tilting disc was 58 +- 2 deg, and was not affected by atrial fibrillation nor by tachycardia up to 160 bpm. There was no change in the maximum opening angle of the disc observed during follow-up period. Good correlation between shortning of the disc opening time and increase in pulse rate suggests excellent adaptation of this prosthesis for tachycardia induced by exercise or electric pacing. However, atrial fibrillation causes time delay in disc closure immediately after prolonged R-R interval. Disc rotation alleviating disc wear was observed in all the patients whether it moves slow or quick. Dysfunction of the disc opening can be readily determined not only by measuring the maximum disc opening angle, but also by observing the characteristic movement indicated in this study. It is concluded from these results that clinical apprication for the convexo-concave Bjoerk-Shiley valve prosthesis is appropriate and cine-radiography is an useful non-invasive examination of cardiac valve prosthesis for long follow-up period.

Evaluation of Gait Performance of a Hemipelvectomy Amputation Walking with a Canadian Prosthesis

Directory of Open Access Journals (Sweden)

M. T. Karimi

2014-01-01

Full Text Available Background. Hemipelvectomy amputation is a surgical procedure in which lower limb and a portion of pelvic are removed. There are a few studies in the literature regarding the performance of subjects with hip disarticulation during walking. However, there is no study on gait analysis of hemipelvectomy subject. Therefore, the aim of this paper was to evaluate the gait and stability of subject with hemipelvectomy amputation. Case Description and Methods. A subject with hemipelvectomy amputation at right side was involved in this study. He used a Canadian prosthesis with single axis ankle joint, 3R21 knee joint, and 7E7 hip joint for more than 10 years. The kinetic and kinematic parameters were collected by a motion analysis system and a Kistler force platform. Findings and Outcomes. There was a significant difference between knee, hip, and ankle range of motions and their moments in the sound and prosthesis sides. In the other side, the stability of the subject in the anteroposterior direction seems to be better than that in the mediolateral direction. Conclusions. There was a significant asymmetry between the kinetic and kinematic performance of the sound and prosthesis sides, which may be due to lack of muscular power and alignment of prosthesis components.

Research and development of a versatile portable speech prosthesis

Science.gov (United States)

1981-01-01

The Versatile Portable Speech Prosthesis (VPSP), a synthetic speech output communication aid for non-speaking people is described. It was intended initially for severely physically limited people with cerebral palsy who are in electric wheelchairs. Hence, it was designed to be placed on a wheelchair and powered from a wheelchair battery. It can easily be separated from the wheelchair. The VPSP is versatile because it is designed to accept any means of single switch, multiple switch, or keyboard control which physically limited people have the ability to use. It is portable because it is mounted on and can go with the electric wheelchair. It is a speech prosthesis, obviously, because it speaks with a synthetic voice for people unable to speak with their own voices. Both hardware and software are described.

Dextran/Albumin hydrogel sealant for Dacron(R) vascular prosthesis.

Science.gov (United States)

Lisman, Anna; Butruk, Beata; Wasiak, Iga; Ciach, Tomasz

2014-05-01

In this paper, the authors describe a novel type of hydrogel coating prepared from the copolymer of human serum albumin and oxidized dextran. The material was designed as a hydrogel sealant for polyester (Dacron®)-based vascular grafts. Dextran was chosen as a coating material due to its anti-thrombogenic properties. Prepared hydrogels were compared with similar, already known biomaterial made from gelatine with the same cross-linking agent. Obtained hydrogels, prepared from various ratios of oxidized dextran/albumin or oxidized dextran/gelatine, showed different cross-linking densities, which caused differences in swelling, degradation rate and mechanical properties. Permeability tests confirmed the complete tightness of the hydrogel-modified prosthesis. Results showed that application of the hydrogel coating provided leakage-free prosthesis and eliminated the need of pre-clotting.

21 CFR 888.3358 - Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint metal/polymer/metal semi-constrained... Devices § 888.3358 Hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis. (a) Identification. A hip joint metal/polymer/metal semi-constrained porous-coated uncemented prosthesis is a device...

21 CFR 888.3390 - Hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) metal/polymer... § 888.3390 Hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metal/polymer cemented or uncemented prosthesis is a two-part...

21 CFR 888.3380 - Hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Hip joint femoral (hemi-hip) trunnion-bearing... Devices § 888.3380 Hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis. (a) Identification. A hip joint femoral (hemi-hip) trunnion-bearing metal/polyacetal cemented prosthesis is a two...

Prosthetic Rehabilitation of Mandibular Defects with Fixed-removable Partial Denture Prosthesis Using Precision Attachment: A Twin Case Report.

Science.gov (United States)

Munot, Vimal Kantilal; Nayakar, Ramesh P; Patil, Raghunath

2017-01-01

The restoration of normal function and esthetic appearance with a dental prosthesis is a major challenge in the rehabilitation of patients who have lost their teeth and surrounding bone because of surgery for oral cyst or tumor. Rehabilitation with fixed or removable prosthesis is even more challenging when the edentulous span is long and the ridge is defective. Anatomic deformities and unfavorable biomechanics encountered in the region of resection add to the misery. In such situation, a fixed-removable prosthesis allows favorable biomechanical stress distribution along with restoration of esthetics, phonetics, comfort, hygiene, and better postoperative care and maintenance. This article describes rehabilitation of two cases with mandibular defects with an attachment-retained fixed-removable hybrid prosthesis.

The Influence of Artificial Cervical Disc Prosthesis Height on the Cervical Biomechanics: A Finite Element Study.

Science.gov (United States)

Yuan, Wei; Zhang, Haiping; Zhou, Xiaoshu; Wu, Weidong; Zhu, Yue

2018-05-01

Artificial cervical disc replacement is expected to maintain normal cervical biomechanics. At present, the effect of the Prestige LP prosthesis height on cervical biomechanics has not been thoroughly studied. This finite element study of the cervical biomechanics aims to predict how the parameters, like range of motion (ROM), adjacent intradiscal pressure, facet joint force, and bone-implant interface stress, are affected by different heights of Prestige LP prostheses. The finite element model of intact cervical spine (C3-C7) was obtained from our previous study, and the model was altered to implant Prestige LP prostheses at the C5-C6 level. The effects of the height of 5, 6, and 7 mm prosthesis replacement on ROM, adjacent intradiscal pressure, facet joint force, as well as the distribution of bone-implant interface stress were examined. ROM, adjacent intradiscal pressure, and facet joint force increased with the prosthesis height, whereas ROM and facet joint force decreased at C5-C6. The maximal stress on the inferior surface of the prostheses was greater than that on the superior surface, and the stresses increased with the prosthesis height. The biomechanical changes were slightly affected by the height of 5 and 6 mm prostheses, but were strongly affected by the 7-mm prosthesis. An appropriate height of the Prestige LP prosthesis can preserve normal ROM, adjacent intradiscal pressure, and facet joint force. Prostheses with a height of ≥2 mm than normal can lead to marked changes in the cervical biomechanics and bone-implant interface stress. Copyright © 2018 Elsevier Inc. All rights reserved.

Finite element analysis of stresses in fixed prosthesis and cement layer using a three-dimensional model

Directory of Open Access Journals (Sweden)

Arunachalam Sangeetha

2012-01-01

Full Text Available Context: To understand the effect of masticatory and parafunctional forces on the integrity of the prosthesis and the underlying cement layer. Aims: The purpose of this study was to evaluate the stress pattern in the cement layer and the fixed prosthesis, on subjecting a three-dimensional finite element model to simulated occlusal loading. Materials and Methods: Three-dimensional finite element model was simulated to replace missing mandibular first molar with second premolar and second molar as abutments. The model was subjected to a range of occlusal loads (20, 30, 40 MPa in two different directions - vertical and 30° to the vertical. The cements (zinc phosphate, polycarboxylate, glass ionomer, and composite were modeled with two cement thicknesses - 25 and 100 μm. Stresses were determined in certain reference points in fixed prosthesis and the cement layer. Statistical Analysis Used: The stress values are mathematic calculations without variance; hence, statistical analysis is not routinely required. Results: Stress levels were calculated according to Von Mises criteria for each node. Maximum stresses were recorded at the occlusal surface, axio-gingival corners, followed by axial wall. The stresses were greater with lateral load and with 100-μm cement thickness. Results revealed higher stresses for zinc phosphate cement, followed by composites. Conclusions: The thinner cement interfaces favor the success of the prosthesis. The stresses in the prosthesis suggest rounding of axio-gingival corners and a well-established finish line as important factors in maintaining the integrity of the prosthesis.

21 CFR 874.3695 - Mandibular implant facial prosthesis.

Science.gov (United States)

2010-04-01

... made of materials such as stainless steel, tantalum, titanium, cobalt-chromium based alloy... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Mandibular implant facial prosthesis. 874.3695... (CONTINUED) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Prosthetic Devices § 874.3695 Mandibular implant...

Biomechanical conceptual design of a passive transfemoral prosthesis.

NARCIS (Netherlands)

Ünal, Ramazan; Carloni, Raffaella; Hekman, Edsko E.G.; Stramigioli, Stefano; Koopman, Hubertus F.J.M.

In this study, we present the conceptual design of a fully-passive transfemoral prosthesis. The proposed design is inspired by the analysis of the musculo-skeletal activity of the healthy human leg. In order to realize an energy efficient device, we introduce three storage elements, which are

Autoinflation Leading to Failure of Two-Piece Ambicor Implantable Penile Prosthesis: An Outcome from a Methodical Treatment of Recalcitrant Stuttering Priapism

Directory of Open Access Journals (Sweden)

R. Charles Welliver

2014-01-01

Full Text Available Introduction. We present the case of a patient who received a two-piece Ambicor penile prosthesis for idiopathic recurrent “stuttering” priapism refractory to other treatment options. The patient returned unable to deflate the device due to an interesting anatomically induced mechanical failure. Aims. To describe the method and findings of this inflatable prosthesis failure. Results. Prosthesis failure occurred due to restrictive corporal diameter and the unique characteristics of fluid reservoir location in the two-piece inflatable prosthesis. The patient was successfully converted to a semirigid prosthesis with resolution of the pain that was due to his prosthesis autoinflation. Conclusion. Stuttering priapism remains a challenging clinical problem. Penile implantation is a reasonable long-term solution in a patient refractory to less invasive options. In patients with fibrotic corpora, a malleable device should be considered (at least temporarily if unable to dilate comfortably to 13 mm.

Effects of Prosthesis Stem Tapers on Stress Distribution of Cemented Hip Arthroplasty

International Nuclear Information System (INIS)

Abdullah, Abdul Halim; Nor, Mohd Asri Mohd; Saman, Alias Mohd; Tamin, Mohd Nasir; Kadir, Mohammed Rafiq Abdul

2010-01-01

Aseptic loosening effects are critical issues in encouraging long term stability of cemented hip arthroplasty. Stress shielding is believed to be an important factor that contributes to the aseptic loosening problems. The numerous changes in the prosthesis stem design are intended to minimize the stress shielding and aseptic loosening problems and to improve the long term performance of the implants. In this study, the stress distribution in cemented hip arthroplasty is established using finite element method. The taper of the prosthesis is designed to be 3 deg. at anterior/posterior, 3 deg. at medial/lateral and 10 deg. from wide lateral to narrow medial. Major muscle loads and contact forces are simulated for walking (toe-off phase) and stair climbing load cases. Effects of prosthesis stem tapers on the resulting stress distribution are investigated. Results show that compressive stress dominates in the medial plane while tensile stress in the lateral plane of the femur. The corresponding stress levels of intact femur for walking and stair-climbing load cases are 22 and 29 MPa, respectively. The magnitude of Tresca stress for the THA femur in stair-climbing load case remains higher in the region of 85 MPa while the walking load case induces around 40 MPa. The stress range in the straight and single taper stem prosthesis is lower than 260 MPa, while localized Tresca stress is in the order of the yield strength of Ti-6Al-4V alloy for double and triple taper stem design.

Effect of joining the sectioned implant-supported prosthesis on the peri-implant strain generated in simulated mandibular model.

Science.gov (United States)

Singh, Ipsha; Nair, K Chandrasekharan; Shetty, Jayakar

2017-01-01

The aim of this study is to evaluate the strain developed in simulated mandibular model before and after the joining of an implant-supported screw-retained prosthesis by different joining techniques, namely, arc welding, laser welding, and soldering. A specimen simulating a mandibular edentulous ridge was fabricated in heat-cured acrylic resin. 4-mm holes were drilled in the following tooth positions; 36, 33, 43, 46. Implant analogs were placed in the holes. University of California, Los Angeles, abutment was attached to the implant fixture. Eight strain gauges were attached to the acrylic resin model. Six similar models were made. Implant-supported screw-retained fixed prosthesis was fabricated in nickel-chromium alloy. A load of 400 N was applied on the prosthesis using universal testing machine. Resultant strain was measured in each strain gauge. All the prostheses were sectioned at the area between 36 and 33, 33 and 43, and 43 and 46 using 35 micrometer carborundum disc, and strain was measured in each strain gauge after applying a load of 400 N on the prosthesis. Specimens were joined by arc welding, soldering, and laser welding. After joining, a load of 400 N was applied on each prosthesis and the resultant strain was measured in each strain gauge. Highest mean strain values were recorded before sectioning of the prostheses (889.9 microstrains). Lowest mean strain values were recorded after sectioning the prosthesis and before reuniting it (225.0 microstrains). Sectioning and reuniting the long-span implant prosthesis was found to be a significant factor in influencing the peri-implant strain.

Antiproton compression and radial measurements

CERN Document Server

Andresen, G B; Bowe, P D; Bray, C C; Butler, E; Cesar, C L; Chapman, S; Charlton, M; Fajans, J; Fujiwara, M C; Funakoshi, R; Gill, D R; Hangst, J S; Hardy, W N; Hayano, R S; Hayden, M E; Humphries, A J; Hydomako, R; Jenkins, M J; Jorgensen, L V; Kurchaninov, L; Lambo, R; Madsen, N; Nolan, P; Olchanski, K; Olin, A; Page R D; Povilus, A; Pusa, P; Robicheaux, F; Sarid, E; Seif El Nasr, S; Silveira, D M; Storey, J W; Thompson, R I; Van der Werf, D P; Wurtele, J S; Yamazaki, Y

2008-01-01

Control of the radial profile of trapped antiproton clouds is critical to trapping antihydrogen. We report detailed measurements of the radial manipulation of antiproton clouds, including areal density compressions by factors as large as ten, achieved by manipulating spatially overlapped electron plasmas. We show detailed measurements of the near-axis antiproton radial profile, and its relation to that of the electron plasma. We also measure the outer radial profile by ejecting antiprotons to the trap wall using an octupole magnet.

Three-dimensional display of femoral head cartilage thickness maps from MR images

International Nuclear Information System (INIS)

Rubin, R.A.; Dolecki, M.; Rubash, H.E.; Thaete, F.L.; Hernden, J.H.

1990-01-01

This paper reports on the development of methods for three-dimensional display and analysis of the articular cartilage of the hip from MR images. Cadaveric femoral head specimens were images with three-dimensional GRASS MR imaging. Data were analyzed on a SUN workstation with original software, the ANALYZE package from Richard Robb's Biomedical Research Group at the Mayo Clinic, and SUN's Voxvu program. The articular cartilage was isolated by manually segmenting images. An original computer ray tracing method measured the cartilage thickness radially and produced movies of a rotating femoral head, displaying brightness proportional to cartilage thickness

Effects of radial diffuser hydraulic design on a double-suction centrifugal pump

Science.gov (United States)

Hou, H. C.; Zhang, Y. X.; Xu, C.; Zhang, J. Y.; Li, Z. L.

2016-05-01

In order to study effects of radial diffuser on hydraulic performance of crude oil pump, the steady CFD numerical method is applied and one large double-suction oil pump running in long-distance pipeline is considered. The research focuses on analysing the influence of its diffuser vane profile on hydraulic performance of oil pump. The four different types of cylindrical vane have been designed by in-house codes mainly including double arcs (DA), triple arcs (TA), equiangular spiral line (ES) and linear variable angle spiral line (LVS). During design process diffuser vane angles at inlet and outlet are tentatively given within a certain range and then the wrapping angle of the four types of diffuser vanes can be calculated automatically. Under the given inlet and outlet angles, the linear variable angle spiral line profile has the biggest wrapping angle and profile length which is good to delay channel diffusion but bring more friction hydraulic loss. Finally the vane camber line is thickened at the certain uniform thickness distribution and the 3D diffuser models are generated. The whole flow passage of oil pump with different types of diffusers under various flow rate conditions are numerically simulated based on RNG k-ɛ turbulent model and SIMPLEC algorithm. The numerical results show that different types of diffusers can bring about great difference on the hydraulic performance of oil pump, of which the ES profile diffuser with its proper setting angle shows the best hydraulic performance and its inner flow field is improved obviously. Compared with the head data from model sample, all designed diffusers can make a certain improvement on head characteristic. At the large flow rate conditions the hydraulic efficiency increases obviously and the best efficiency point shift to the large flow rate range. The ES profile diffuser embodies the better advantages on pump performance which can be explained theoretically that the diffuser actually acts as a diffusion

[The esthetics of lower limb prosthesis].

Science.gov (United States)

Gardrat, Franck

2015-01-01

The amputation, which is upper or lower limb, entails important consequences and often traumatic into subject amputee from a physical, psychological, interpersonal and social point of view. It acts on the body image unleashing different psychological disorders and alterations in the social and professional reality. The aesthetic prosthesis can be considered a good support to help the person regain a new body image of themselves, facilitating the process of physical rehabilitation and social integration.

Impact of removable partial denture prosthesis on chewing efficiency

Science.gov (United States)

BESSADET, Marion; NICOLAS, Emmanuel; SOCHAT, Marine; HENNEQUIN, Martine; VEYRUNE, Jean-Luc

2013-01-01

Removable partial denture prostheses are still being used for anatomic, medical and economic reasons. However, the impact on chewing parameters is poorly described. Objectives The objective of this study was to estimate the impact of removable partial denture prosthesis on masticatory parameters. Material and Methods Nineteen removable partial denture prosthesis (RPDP) wearers participated in the study. Among them, 10 subjects were Kennedy Class III partially edentulous and 9 with posterior edentulism (Class I). All presented a complete and full dentate opposing arch. The subjects chewed samples of carrots and peanuts with and without their prosthesis. The granulometry of the expectorated boluses from carrot and peanuts was characterized by median particle size (D50), determined at the natural point of swallowing. Number of chewing cycles (CC), chewing time (CT) and chewing frequency (CF=CC/CT) were video recorded. Results With RPDP, the mean D50 values for carrot and peanuts were lower [Repeated Model Procedures (RMP), F=15, p<0.001] regardless of the type of Kennedy Class. For each food, mean CC, CT and CF values recorded decreased (RMP, F=18, F=9, and F=20 respectively, p<0.01). With or without RPD, the boluses' granulometry values were above the masticatory normative index (MNI) determined as 4,000 µm. Conclusion RPDP rehabilitation improves the ability to reduce the bolus particle size, but does not reestablish fully the masticatory function. Clinical relevance This study encourages the clinical improvement of oral rehabilitation procedure. PMID:24212983

Pseudo-capsule “coffin effect”: How to prevent penile retraction after implant of three-piece inflatable prosthesis

Directory of Open Access Journals (Sweden)

Enrico Caraceni

2014-06-01

Full Text Available Objective: Following three-component implantation of a penile prosthesis, some patients are dissatisfied with their penile length. This may be due to the procedure by itself or pre-existing risk factors or psychological reasons. We supposed that formation of a restricted pseudo-capsule due to a late prosthesis activation can inhibit later system expansion. We aimed to identify the presence or absence of penile retraction after implant and to prevent it by immediate prosthesis activation after implantation. Material and methods. Forty-six patients operated with three-piece inflatable penile prosthesis (AMS 700 CX o LGX were enrolled. In 27 patients prosthesis was first activated four weeks after surgery (NEA group and in 19 patients prosthesis was activated immediately after surgery (DEA group. Length and girth of the penis was evaluated before (in DEA group and after the surgical procedure. Results. The average post implant dorsal length of the erect penis in group NEA was found 3.28 cm shorter than in group with early activation (DEA. In DEA group there was no lenght difference between pre-operative stretching (14.57 cm and post operative erection (14.98 cm. When early activation was not performed, the clinical result was a smaller penis in erect phase. Conclusion. Reduced lenght of the penis after implantation can be caused by the presence of a pseudo-capsule that limits the elongation of the prosthesis and of the penis (“coffin effect”. Timing of first activation seems to be the key in order to prevent the risk of penile retraction after implantation. Early activation is identified as the best measure to maintain the length of the pre implant erect penis after the prosthetic hydraulic implant.

Penile prosthesis implantation in Chinese patients with severe erectile dysfunction: 10-year experience

Science.gov (United States)

Song, Wei-Dong; Yuan, Yi-Ming; Cui, Wan-Shou; Wu, Alex K; Zhu, Yi-Chen; Liu, Jing; Wang, Lin; Bai, Guang-Yi; Peng, Jing; Zhang, Zhi-Chao; Gao, Bing; Guo, Ying-Lu; Lue, Tom F; Xin, Zhong-Cheng

2013-01-01

We retrospectively evaluated the clinical outcome of penile prosthesis implantation (PPI) in Chinese patients with severe erectile dysfunction (SED). From July 2000 to December 2011, 224 patients (mean age: 35.9±11.8 years, range: 20–75 years) with SED underwent PPI by experienced surgeon according to standard PPI procedure at our centre. A malleable prosthesis (AMS 650) was implanted in 45 cases (20.1%), and a three-piece inflatable prosthesis (AMS 700 CXM or AMS 700 CXR) was implanted in 179 cases (79.9%). Surgical outcomes, including postoperative complications, clinical efficacy and couple satisfaction, were evaluated over than 6 months postoperatively using medical record abstraction, IIEF-5, quality of life (QoL) scores, and the patient/partner sexual satisfaction score proposed by Bhojwani et al. Of the 224 patients eligible for the study, 201 subjects (89.7%) completed follow-up. All of patients could perform sexual intercourse post PPI with the mean postoperative IIEF-5 and QoL scores were 20.02±2.32 and 5.28±0.76, respectively, which were significantly improved compared with the preoperative scores (6.29±1.5 and 2.13±0.84, Preported by 178 men (88.6%), and overall satisfaction with the PPI surgery was reported by 89.0% of men and 82.5% of partners. Patient satisfaction in the three-piece inflatable prosthesis group was higher than in the malleable prosthesis group (P<0.05). Satisfaction, however, between the types of prostheses, did not differ in the partner survey. PPI is a safe and effective treatment option for Chinese patients with SED and experienced surgeon perform PPI according to standard PPI procedure could reduce the postoperative complications of PPI and could improve patient satisfaction ratio and QoL. PMID:23872664

Debridement, antibiotics, irrigation, and retention (DAIR) of the prosthesis after hip hemiarthroplasty infections. Does it work?

Science.gov (United States)

Kazimoglu, Cemal; Yalcin, Nadir; Onvural, Burak; Akcay, Serkan; Agus, Haluk

2015-08-01

Debridement, antibiotic, and implant retention (DAIR) is an attractive treatment modality after hip hemiarthroplasty (HA) infections. Data about the success of the procedure after acute onset infections is lacking. The aim of this study was to analyze the clinical outcome and associated risk factors. A multicenter, retrospective cohort study was designed, including 39 patients with acute onset prosthetic infection who had undergone debridement and irrigation with prosthesis retention. The primary outcome measure was infection eradication without prosthesis removal. We also analyzed how the success rate was influenced by the length of the interval between implantation of the prosthesis and the beginning of the treatment. The overall success rate was 41%. Sedimentation rate over 60 mm/h and the longer duration (2 weeks) after prosthesis implantation were found as factors negatively influencing the success rate. Our results indicated limited success to DAIR- treated patients with infected HA. The high failure rate of DAIR treatment after 2 weeks from the implantation should be taken into consideration.

Chest-wall reconstruction with a customized titanium-alloy prosthesis fabricated by 3D printing and rapid prototyping.

Science.gov (United States)

Wen, Xiaopeng; Gao, Shan; Feng, Jinteng; Li, Shuo; Gao, Rui; Zhang, Guangjian

2018-01-08

As 3D printing technology emerge, there is increasing demand for a more customizable implant in the repair of chest-wall bony defects. This article aims to present a custom design and fabrication method for repairing bony defects of the chest wall following tumour resection, which utilizes three-dimensional (3D) printing and rapid-prototyping technology. A 3D model of the bony defect was generated after acquiring helical CT data. A customized prosthesis was then designed using computer-aided design (CAD) and mirroring technology, and fabricated using titanium-alloy powder. The mechanical properties of the printed prosthesis were investigated using ANSYS software. The yield strength of the titanium-alloy prosthesis was 950 ± 14 MPa (mean ± SD), and its ultimate strength was 1005 ± 26 MPa. The 3D finite element analyses revealed that the equivalent stress distribution of each prosthesis was unifrom. The symmetry and reconstruction quality contour of the repaired chest wall was satisfactory. No rejection or infection occurred during the 6-month follow-up period. Chest-wall reconstruction with a customized titanium-alloy prosthesis is a reliable technique for repairing bony defects.

Prosthetic rehabilitation of mandibular defects with fixed-removable partial denture prosthesis using precision attachment: A twin case report

Directory of Open Access Journals (Sweden)

Vimal Kantilal Munot

2017-01-01

Full Text Available The restoration of normal function and esthetic appearance with a dental prosthesis is a major challenge in the rehabilitation of patients who have lost their teeth and surrounding bone because of surgery for oral cyst or tumor. Rehabilitation with fixed or removable prosthesis is even more challenging when the edentulous span is long and the ridge is defective. Anatomic deformities and unfavorable biomechanics encountered in the region of resection add to the misery. In such situation, a fixed-removable prosthesis allows favorable biomechanical stress distribution along with restoration of esthetics, phonetics, comfort, hygiene, and better postoperative care and maintenance. This article describes rehabilitation of two cases with mandibular defects with an attachment-retained fixed-removable hybrid prosthesis.

COMPARISON OF CULTURE OF SYNOVIAL FLUID, PERIPROSTHETIC TISSUE AND PROSTHESIS SONICATE FOR THE DIAGNOSIS OF KNEE PROSTHESIS INFECTION

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Andrej Trampuž

2003-03-01

Full Text Available Background. Synovial fluid and periprosthetic tissue specimens are the standard specimens cultured for the diagnosis of prosthetic joint infection (PJI. We hypothesize that ultrasonication of the explanted prosthesis may improve diagnosis of PJI by dislodging biofilm bacteria from the prosthesis surface and improve the sensitivity and specificity of diagnosis of PJI.Methods. Included were patients undergoing knee prosthesis exchange for septic or biomechanical failure and have not received antimicrobial therapy in the last 2 weeks prior specimen collection. Cultures of synovial fluid and periprosthetic tissue specimens were performed per the usual clinical practice. Additionally, explanted joint components were sonicated for 5 minutes at frequency 40 kHz in sterile Ringer’s solution; aliquots of 0.5 ml sonicate were plated onto five aerobic and five anaerobic blood agar plates, and incubated at 37 °C and examined for the next seven days. The number and identity of each colony morphology was recorded.Results. 35 patients undergoing knee replacement have been studied (24 for aseptic biomechanical failure and 11 for suspected PJI. In patients with PJI, coagulase-negative staphylococci (7 cases, Corynebacterium spp. (2 cases, Staphylococcus aureus (1 case, and viridans group streptococcus (1 case were recovered. Culture sensitivity and specificity were for synovial fluid 88% and 100%, for periprosthetic tissue 83% and 81%, and for explant sonicate 91% and 100%, respectively. In sonicate cultures higher numbers of microorganisms than in periprosthetic tissue cultures were consistently detected.Conclusions. Using synovial fluid, periprosthetic tissue, and explant sonicate cultures, 12%, 17% and 9% of PJI were missed, respectively. Explant sonicate cultures were the most sensitive with respect to the diagnosis of PJI, indicating that explant ultrasonication may improve bacterial recovery. In sonicate cultures, infecting organisms were detected in

The clinical relevance of advanced artificial feedback in the control of a multi-functional myoelectric prosthesis.

Science.gov (United States)

Markovic, Marko; Schweisfurth, Meike A; Engels, Leonard F; Bentz, Tashina; Wüstefeld, Daniela; Farina, Dario; Dosen, Strahinja

2018-03-27

To effectively replace the human hand, a prosthesis should seamlessly respond to user intentions but also convey sensory information back to the user. Restoration of sensory feedback is rated highly by the prosthesis users, and feedback is critical for grasping in able-bodied subjects. Nonetheless, the benefits of feedback in prosthetics are still debated. The lack of consensus is likely due to the complex nature of sensory feedback during prosthesis control, so that its effectiveness depends on multiple factors (e.g., task complexity, user learning). We evaluated the impact of these factors with a longitudinal assessment in six amputee subjects, using a clinical setup (socket, embedded control) and a range of tasks (box and blocks, block turn, clothespin and cups relocation). To provide feedback, we have proposed a novel vibrotactile stimulation scheme capable of transmitting multiple variables from a multifunction prosthesis. The subjects wore a bracelet with four by two uniformly placed vibro-tactors providing information on contact, prosthesis state (active function), and grasping force. The subjects also completed a questionnaire for the subjective evaluation of the feedback. The tests demonstrated that feedback was beneficial only in the complex tasks (block turn, clothespin and cups relocation), and that the training had an important, task-dependent impact. In the clothespin relocation and block turn tasks, training allowed the subjects to establish successful feedforward control, and therefore, the feedback became redundant. In the cups relocation task, however, the subjects needed some training to learn how to properly exploit the feedback. The subjective evaluation of the feedback was consistently positive, regardless of the objective benefits. These results underline the multifaceted nature of closed-loop prosthesis control as, depending on the context, the same feedback interface can have different impact on performance. Finally, even if the closed

Investigations of radial electric field and global circulation layer in limiter tokamaks

International Nuclear Information System (INIS)

Zagorski, R.; Gerhauser, H.; Lehnen, M.; Loarer, T.

2002-01-01

An updated version of the 2D multifluid code TECXY is used to study the radial electric field structure and the appearance of a global circulation layer (GCL) inside the separatrix of the limiter tokamaks TEXTOR-94 and Tore-Supra-CIEL. The dependence of the driving forces on device geometry, limiter position, magnetic field orientation, impurity content and other parameters is investigated. The centrifugal force in the vicinity of the limiter head always determines the direction of the poloidal velocity in the GCL. There is good agreement with experimentally measured profiles of the poloidal velocity at the TEXTOR low field side. (orig.)

The Use of CAD/CAM Trial Pattern for Facial Prosthesis Fabrication of a Maxillofacial Patient with Large Defect

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Nina Ariani

2017-12-01

Full Text Available Treatment of maxillofacial patients needs a multidisciplinary approach of several expertise based on the complexityof the case. Prosthodontists often work together with e.g. ENT, oral or plastic surgeons to provide patient with betterprosthesis and optimum treatment. Case report: A 55 years old male was referred to Dental Teaching Hospital ofUniversitas Indonesia for facial prosthesis fabrication. Patient had undergone squamous cell carcinoma ablationsurgery that encompassed nose, cheek, sinuses, upper lip and most of the hard palate. Due to the extensive natureof the defect, Department of Prosthodontics collaborated with Department of Biomedical Engineering to employ3D printing technique using general purpose machine for fabricating the trial pattern for the prosthesis, withattention given especially to margin areas and facial contours. This technique helps for prosthesis fabrication ofthis patient because manual wax carving is no longer necessary. Wax carving usually is a labor/skill intensive stepand takes longer time. Conclusion: 3D printing of the trial pattern for the prosthesis help minimizes the labor/skill intensive part of facial prosthesis fabrication.

Quantitating the effect of prosthesis design on femoral remodeling using high-resolution region-free densitometric analysis (DXA-RFA)

DEFF Research Database (Denmark)

Farzi, Mohsen; Morris, Richard M; Penny, Jeannette

2017-01-01

Dual energy X-ray absorptiometry (DXA) is the reference standard method used to study bone mineral density (BMD) after total hip arthroplasty (THA). However, the subtle, spatially complex changes in bone mass due to strain-adaptive bone remodeling relevant to different prosthesis designs are not ......Dual energy X-ray absorptiometry (DXA) is the reference standard method used to study bone mineral density (BMD) after total hip arthroplasty (THA). However, the subtle, spatially complex changes in bone mass due to strain-adaptive bone remodeling relevant to different prosthesis designs...... using scans acquired during two previous randomized clinical trials (2004 to 2009); one comparing three cemented prosthesis design geometries, and the other comparing a hip resurfacing versus a conventional cementless prosthesis. DXA RFA resolved subtle differences in magnitude and area of bone...... remodeling between prosthesis designs not previously identified in conventional DXA analyses. A mean bone loss of 10.3%, 12.1%, and 11.1% occurred for the three cemented prostheses within a bone area fraction of 14.8%, 14.4%, and 6.2%, mostly within the lesser trochanter (p 

Cross-cultural validation of the Prosthesis Evaluation Questionnaire in vascular amputees fitted with prostheses in Spain.

Science.gov (United States)

Benavent, Jose Vicente; Igual, Celedonia; Mora, Enrique; Antonio, Rosa; Tenias, Jose Maria

2016-12-01

The lack of specific prosthetic-related outcome instruments for Spanish amputees must be addressed. To elaborate a culturally equivalent version of the Prosthesis Evaluation Questionnaire in the Spanish language. Cross-cultural questionnaire validation. Two-step process for cultural adaptation: forward and backward translations of English original and Spanish translated versions; assessment of both construct and criterion validity and reliability in a group of vascular amputees. A total of 61 patients were recruited, 44 men (72.1%) and 17 women (27.9%), with a median age of 71.1 years (standard deviation: 7.7 years; range: 51-87 years). In the Prosthesis Evaluation Questionnaire-Spanish, the lowest scores were for gait and frustration, and the highest scores were for noise and stump health. Internal consistency of the questionnaire was acceptable (>0.70) for four of the scales used in the Prosthesis Evaluation Questionnaire but poor (<0.50) for the scales relating to appearance and stump health. Correlations with the quality-of-life levels as measured by the Short Form-36 were positive and mostly significant. Prosthesis Evaluation Questionnaire-Spanish could assess the quality of life in patients who have undergone vascular amputations and then been fitted with a prosthetic limb. The questionnaire shows adequate criteria validity when compared with other instruments for measuring quality of life. The Prosthesis Evaluation Questionnaire-Spanish could be a valid and reliable instrument for assessing adaptation to prostheses in vascular amputees. The questionnaire adds information relevant to the patient and the physician and may identify cases with poor expected adaptation to the prosthesis. © The International Society for Prosthetics and Orthotics 2015.

Design of a Fully-Passive Transfemoral Prosthesis Prototype

NARCIS (Netherlands)

Behrens, Sebastiaan Maria; Behrens, S.M.; Ünal, Ramazan; Unal, R.; Hekman, Edsko E.G.; Carloni, Raffaella; Stramigioli, Stefano; Koopman, Hubertus F.J.M.

In this study, we present the mechanical design of a prototype of a fully-passive transfemoral prosthesis for normal walking. The conceptual working principle at the basis of the design is inspired by the power flow in human gait, with the main purpose of realizing an energy efficient device. The

Stability of radial swirl flows

International Nuclear Information System (INIS)

Dou, H S; Khoo, B C

2012-01-01

The energy gradient theory is used to examine the stability of radial swirl flows. It is found that the flow of free vortex is always stable, while the introduction of a radial flow will induce the flow to be unstable. It is also shown that the pure radial flow is stable. Thus, there is a flow angle between the pure circumferential flow and the pure radial flow at which the flow is most unstable. It is demonstrated that the magnitude of this flow angle is related to the Re number based on the radial flow rate, and it is near the pure circumferential flow. The result obtained in this study is useful for the design of vaneless diffusers of centrifugal compressors and pumps as well as other industrial devices.

Effect of joining the sectioned implant-supported prosthesis on the peri-implant strain generated in simulated mandibular model

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Ipsha Singh

2017-01-01

Full Text Available Aim: The aim of this study is to evaluate the strain developed in simulated mandibular model before and after the joining of an implant-supported screw-retained prosthesis by different joining techniques, namely, arc welding, laser welding, and soldering. Materials and Methods: A specimen simulating a mandibular edentulous ridge was fabricated in heat-cured acrylic resin. 4-mm holes were drilled in the following tooth positions; 36, 33, 43, 46. Implant analogs were placed in the holes. University of California, Los Angeles, abutment was attached to the implant fixture. Eight strain gauges were attached to the acrylic resin model. Six similar models were made. Implant-supported screw-retained fixed prosthesis was fabricated in nickel-chromium alloy. A load of 400 N was applied on the prosthesis using universal testing machine. Resultant strain was measured in each strain gauge. All the prostheses were sectioned at the area between 36 and 33, 33 and 43, and 43 and 46 using 35 micrometer carborundum disc, and strain was measured in each strain gauge after applying a load of 400 N on the prosthesis. Specimens were joined by arc welding, soldering, and laser welding. After joining, a load of 400 N was applied on each prosthesis and the resultant strain was measured in each strain gauge. Results: Highest mean strain values were recorded before sectioning of the prostheses (889.9 microstrains. Lowest mean strain values were recorded after sectioning the prosthesis and before reuniting it (225.0 microstrains. Conclusions: Sectioning and reuniting the long-span implant prosthesis was found to be a significant factor in influencing the peri-implant strain.

Femoral head necrosis; Hueftkopfnekrose

Energy Technology Data Exchange (ETDEWEB)

Kramer, J.; Scheurecker, G.; Scheurecker, A.; Stoeger, A.; Huber, A. [Roentgeninstitut am Schillerpark, Linz (Austria); Hofmann, S. [Orthopaedisches Landeskrankenhaus Stolzalpe (Austria)

2009-05-15

The epidemiology and pathohistogenesis of avascular femoral head necrosis has still not been clarified in detail. Because the course of the disease runs in stages and over a long time period nearly always culminates in the necessity for a total hip prosthesis, an exact radiological evaluation is of paramount importance for the treatment. There is a need for a common staging system to enable comparison of different therapy concepts and especially their long-term results. In this article the ARCO staging system is described in full detail, which includes all radiological modalities as well as histopathological alterations. (orig.) [German] Bei der avaskulaeren Femurkopfnekrose handelt es sich um ein Krankheitsbild, dessen Ursachen noch immer nicht vollstaendig geklaert sind. Da die Erkrankung stadienhaft verlaeuft und ueber einen laengeren Zeitraum betrachtet nahezu immer in einem prothetischen Hueftersatz muendet, ist eine genaue radiologische Abklaerung fuer die Behandlung von enormer Bedeutung. Um Langzeiterfolge verschiedener Therapiekonzepte vergleichen zu koennen, sind eine exakte Beschreibung und darauf basierend die Verwendung einer einheitlichen Stadieneinteilung wuenschenswert. In der vorliegenden Arbeit wird die ARCO-Stadieneinteilung im Detail beschrieben, die alle bildgebenden Methoden beruecksichtigt und histopathologische Veraenderungen mit einbezieht. (orig.)

To Compare the Effect of Pre and Post Weight Bearing Anxiety, Depression in Conventional and Modular Prosthesis on Unilateral Transtibial Amputees

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R. Raja

2014-01-01

Full Text Available Aims and Objectives: To compare the effect of anxiety and depression on unilateral trans tibial amputees those who are using conventional and modular patellar tendon bearing (PTB prosthesis with stump exercises. Material and Methods: A sample of 40 persons with below knee amputation who were trained to wear prosthesis were studied with an experimental comparative study design. Patients who were admitted at Kempegowda Institute of Medical Sciences and Research Centre, Bangalore, K. S. Hegde Medical Academy and Research Centre Mangalore, (N=150 who underwent unilateral transtibial, transfemoral and other amputations between August 2009 - December 2011. To find out peri and postoperative prosthetic fitting, anxiety and depression level of transtibial amputees who wear conventional and modular PTB prosthesis. 3 years of experimental comparative study reveals that the outcome measures of peri and post-operative anxiety and depression level while using conventional PTB prosthesis with stump exercises and modular PTB prosthesis with stump exercises on unilateral transtibial amputees. Results: The unilateral transtibial amputees who were trained with modular prosthesis along with stump exercises group patients anxiety and depression levels are reduced as compared to the unilateral transtibial amputees who were trained with conventional PTB prosthesis along with stump exercises. There is no significant difference seen in both the groups while giving stump exercises alone. Conclusion: The unilateral transtibial amputees who were trained with modular prosthesis along with stump exercises group, patient’s anxiety and depression levels are reduced drastically.

Treatment of sharp mandibular alveolar process with hybrid prosthesis

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Sukaedi Sukaedi

2010-09-01

Full Text Available Background: Losing posterior teeth for a long time would occasionally lead to the sharpening of alveolar process. The removable partial denture usually have problems when used during mastication, because of the pressure on the mucosa under the alveolar ridge. Purpose: The purpose of this case report was to manage patients with sharp mandibular alveolar process by wearing hybrid prosthesis with extra coronal precision attachment retention and soft liner on the surface base beneath the removable partial denture. Case: A 76 years old woman visited the Prosthodontic Clinic Faculty of Dentistry Airlangga University. The patient had a long span bridge on the upper jaw and a free end acrylic removable partial denture on the lower jaw. She was having problems with mastication. The patient did not wear her lower denture because of the discomfort with it during mastication. Hence, she would like to replace it with a new removable partial denture. Case management: The patient was treated by wearing a hybrid prosthesis with extra coronal precision attachment on the lower jaw. Soft liner was applied on the surface of the removable partial denture. Hybrid prosthesis is a complex denture consisting of removable partial denture and fixed bridge. Conclusion: It concluded that after restoration, the patient had no problems with sharp alveolar process with her new denture, and she was able to masticate well.Latar belakang: Kehilangan geligi posterior dapat menimbulkan processus alveolaris tajam. Gigi tiruan sebagian lepasan mempunyai masalah selama pengunyahan karena adanya tekanan di mukosa di bawah alveolar ridge. Tujuan: Tujuan laporan kasus ini adalah untuk menjelaskan cara menangani pasien yang mempunyai prosesus alveolaris yang tajam di rahang bawah dengan dibuatkan protesis hybrid dengan daya tahan extra coronal precision attachment dan soft liner di permukaan bawah basis gigi tiruan sebagian lepasan. Kasus: Pasien wanita berumur 76 tahun datang di klinik

Removable dental prosthesis as periodontal treatment method

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Aprilia Adenan

2007-11-01

Full Text Available The objectives of prostheses are to restore mastication force, improve esthetics and maintain gingival health. The construction and function of prosthesis restoration are mutually interdependent with condition of periodontal tissues. A properly constructed prosthesis is an integral phase of complete treatment of periodontal disease in order to maintain periodontal tissues health. This paper reports case of a man aged 47 years who came to Dental Specialist Clinic in Oral and Dental Hospital Faculty of Dentistry Universitas Padjadjaran with chief complaint of mobility in almost all his teeth and they seems to look longer. The patient has no systemic disease and did not want his teeth to be extracted. Clinical and panoramic radiographic and laboratoris examinations has been done. During treatment, oclusal adjustment and splinting had been done on tooth 33,34,35 and tooth 44,43 also tooth 43,42 splinting with composite. The following treatment was the acrylic removable partial denture for upper jaw while mandible was fitted a frame denture which functioned as a semi permanent splint. One month post treatment, patien felt comfort and the denture was well functioning.

Excessive strut wear allowing ball-poppet embolization in a DeBakey-Surgitool aortic valve prosthesis.

Science.gov (United States)

Sutherland, R D; Guynes, W A; Nichols, C T; Martinez, H E

1982-01-01

Excessive cage strut wear allowing ball-poppet embolization caused the sudden death of a 47 year old lady in whom a DeBakey-Surgitool aortic prosthesis had been implanted nine years earlier. Patients with this type of prosthesis should have periodic valvular cine fluoroscopy with image intensification to allow visualization of significant strut wear or fracture, and appropriate prosthetic valve replacement.

Extended long term functional outcome of inflatable penile prosthesis in a single institution.

LENUS (Irish Health Repository)

Thomas, A Z

2011-02-01

We sought to evaluate the extended long term functional outcome of the AMS700 three piece inflatable prosthesis in men with erectile dysfunction in a single urological department and assess our revision rates. Patients that underwent first-time insertion or revision of an AMS700 3 piece inflatable penile prosthesis between 1984-2007 were included. Data was obtained from medical records and long term follow up of patients was conducted by telephone interview. The medical records of 38 patients were available for review. Of these 38 men, 56 prostheses were inserted. The mean follow up was 8.4 years (101 months). The revision rate at 50 months postoperatively was 7\\/38 (18%). The overall revision rate was 18\\/38 (47%). The mean time to revision in these 18 patients was 72 months (12-156 months) after initial insertion of AMS700 penile prosthesis. This study highlights that with longer follow u revision rates markedly increase after 72 months.

Modified cementless total coxofemoral prosthesis: development, implantation and clinical evaluation

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S.A. Arias

2013-12-01

Full Text Available The aim of this study was to modify canine coxofemoral prostheses and the clinical evaluation of the implantation. Fifteen canine hips and femora of cadavers were used in order to study the surface points of modification in prostheses and develop a perforation guide. Femoral stems and acetabular components were perforated and coated with biphasic calcium phosphate layer. Twelve young adult male mongrel dogs were implanted with coxofemoral prostheses. Six were operated upon and implanted with cemented canine modular hip prostheses, establishing the control group. The remaining six were implanted with a novel design of cementless porous tricalcic phosphate-hydroxyapatite coated hip prostheses. Clinical and orthopedic performance, complications, and thigh muscular hypotrophy were assessed up to the 120th post-operatory day. After 120 days, animals with cementless prostheses had similar clinical and orthopedic performance compared to the cemented group despite the increased pain thigh hypotrophy. Animals that underwent cementless hip prosthesis evidenced more pain, compared to animals with cemented hip prosthesis that required longer recuperation time. No luxations, two fractures and two isquiatic neurapraxies were identified in the course of the study. Using both the cemented and the bioactive coated cementless model were suitable to dogs, showing clinical satisfactory results. Osseointegration and biological fixation were observed in the animals with the modified cementless hip prosthesis.

Reconstruction of chronic acromioclavicular joint disruption with artificial ligament prosthesis

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Chouhan Devendra Kumar

2013-08-01

Full Text Available 【Abstract】Objective: Management of Rockwood type 3 acromioclavicular disruptions is a matter of debate. Should we adopt conservative or operative measures at first presentation? It is not clear but most of the evidences are in favour of conservative management. We present our expe-rience in managing these patients surgically. Methods: We present a prospective series of eight cases of chronic Rockwood type 3 acromioclavicular joint disruptions treated surgically. Anatomical reconstruction of the coracoclavicular ligament was done by artificial braided polyester ligament prosthesis. Results: All the patients were able to perform daily activities from an average of the 14th postoperative day. All patients felt an improvement in pain, with decrease in ave-rage visual analogue scale from preoperative 6.5 points (range 3-9 points to 2.0 points (range 0-5 points, Constant score from 59% to 91% and American Shoulder and Elbow Surgeons shoulder score from 65 to 93 points postoperatively. These results improved or at least remained stationary on midterm follow-up, and no deterioration was recorded at an average follow-up of 46 months. Conclusion: This midterm outcome analysis of the artificial ligament prosthesis is the first such follow-up study with prosthesis. Our results are encouraging and justify the further use and evaluation of this relatively new and easily reproducible technique. Key words: Acromioclavicular joint; Prostheses and implants; Reconstructive surgical procedures; Ligaments

Task-Oriented Gaming for Transfer to Prosthesis Use

NARCIS (Netherlands)

van Dijk, Ludger; Sluis, van der Corry K.; van Dijk, Hylke W.; Bongers, Raoul M.

2016-01-01

The aim of this study is to establish the effect of task-oriented video gaming on using a myoelectric prosthesis in a basic activity of daily life (ADL). Forty-one able-bodied right-handed participants were randomly assigned to one of four groups. In three of these groups the participants trained to

[Medial unicompartmental knee prosthesis for patients with unicompartmental gonarthrosis

NARCIS (Netherlands)

Kort, N.P.; Deutman, R.; Raay, J.J. van; Horn, J.R. van

2004-01-01

The function and survival time of unicompartmental knee prostheses for patients with severe gonarthrosis have been improved the past few years by developments in their design, the instrumentarium and the surgical technique. A medial unicompartmental knee prosthesis may be indicated in patients with

[Comparison of chemical quality characteristics between radial striations and non-radial striations in tuberous root of Rehmannia glutinosa].

Science.gov (United States)

Xie, Cai-Xia; Zhang, Miao; Li, Ya-Jing; Geng, Xiao-Tong; Wang, Feng-Qing; Zhang, Zhong-Yi

2017-11-01

An HPLC method was established to determine the contents of catalpol, acteoside, rehmaionoside A, rehmaionoside D, leonuride in three part of Rehmanni glutinosa in Beijing No.1 variety R. glutinosa during the growth period, This method, in combination with its HPLC fingerprint was used to evaluate its overall quality characteristics.The results showed that：① the content of main components of R. glutinosa varied in different growth stages ;② there was a great difference of the content of main components between theradial striations and the non-radial striations; ③ the two sections almost have the same content distribution of catalpol, acteoside and rehmaionoside D; ④the content of rehmaionoside A in non-radial striations was higher than that in radial striations,while the content of leonuride in radial striations was higher than that in non-radial striations.; ⑤the HPLC fingerprint of radial striations, non-radial striations and whole root tuber were basically identical, except for the big difference in the content of chemical components. The result of clustering displayed that the radial striations, non-radial striations, and whole root were divided into two groups. In conclusion, there was a significant difference in the quality characteristics of radial striations and non-radial striations of R. glutinosa. This research provides a reference for quality evaluation and geoherbalism of R. glutinosa. Copyright© by the Chinese Pharmaceutical Association.

Survey on the Contemporary Management of Intraoperative Urethral Injuries During Penile Prosthesis Implantation.

Science.gov (United States)

Sexton, Stephanie J; Granieri, Michael A; Lentz, Aaron C

2018-04-01

Intraoperative urethral injury is an uncommon event during the placement of a penile prosthesis, and alternative management strategies have been proposed with continuation of implantation after urethral injury. To evaluate surgeon practices in the management of intraoperative urethral injury. An online survey was sent to the society listservs of the Genitourinary Reconstructive Surgeons (GURS) and the Sexual Medicine Society of North America (SMSNA). Physicians were queried on their fellowship training, experience with penile prosthesis implantation, and management of urethral injuries during prosthesis placement. The response data were analyzed using SAS 9.4 (SAS Institute, Cary, NC, USA). The χ 2 test and Fisher exact test were used to determine associations between variables. Survey responses. 131 survey responses were analyzed. Of the responders, 41.2% were GURS fellowship trained, 19.1% were SMSNA trained, 30.5% were non-fellowship trained, and 9.2% were trained in other fellowships. 25.4% of participants performed more than 50 implantations per year, 37.7% performed 20 to 50 per year, and 36.9% performed fewer than 20 per year. Urethral injury during prosthesis implantation was uncommon, with 26.2% reporting 0 injury, 58.5% reporting 1 to 3 injuries, and 15.4% reporting more than 3 career injuries. Injuries were most commonly encountered during corporal dilation (71.1%) compared with corporal exposure (12.5%) or penile straightening maneuvers (7.0%). There was no statistically significant difference with aborting or continuing implantation among GURS-trained, SMSNA-trained, other fellowship-trained, and non-fellowship-trained surgeons. Of all responders, 55% would abort the procedure after distal urethral injury, whereas 45% would continue the procedure with unilateral or bilateral insertion of cylinders. Patient factors that increased likelihood of terminating the procedure in the case of urethral injury included immunosuppression, spinal cord injury, and

Modified prosthesis for the treatment of malignant esophagotracheal fistula

International Nuclear Information System (INIS)

Buess, G.; Schellong, H.; Kometz, B.; Gruessner, R.J.; Junginger, T.

1988-01-01

Esophagotracheal fistula is usually a sequela of irradiation or laser treatment of advanced carcinoma of the esophagus or the tracheobronchial tree. Resection of the tumor in these cases is not possible, and palliative bypass surgery is highly risky. The peroral placement of a prosthesis is less invasive, but conventional prostheses often fail to occlude the fistula. The authors regularly use an endoscopic multiple-diameter bougie for dilation. After dilation, a specially designed prosthesis is pushed through the tumor stenosis to block the fistula. This procedure can be done without general anesthesia. The funnels of conventional prostheses cannot cover the fistula when there is either a wide, proximal esophagus above the fistula or a high fistula. To cope with this particular situation, a special fistula funnel was developed. It perfectly occludes the fistulas in all patients. Of 21 patients, 19 were discharged without further aspiration

Experimental feasibility study of radial injection cooling of three-pad radial air foil bearings

Science.gov (United States)

Shrestha, Suman K.

Air foil bearings use ambient air as a lubricant allowing environment-friendly operation. When they are designed, installed, and operated properly, air foil bearings are very cost effective and reliable solution to oil-free turbomachinery. Because air is used as a lubricant, there are no mechanical contacts between the rotor and bearings and when the rotor is lifted off the bearing, near frictionless quiet operation is possible. However, due to the high speed operation, thermal management is one of the very important design factors to consider. Most widely accepted practice of the cooling method is axial cooling, which uses cooling air passing through heat exchange channels formed underneath the bearing pad. Advantage is no hardware modification to implement the axial cooling because elastic foundation structure of foil bearing serves as a heat exchange channels. Disadvantage is axial temperature gradient on the journal shaft and bearing. This work presents the experimental feasibility study of alternative cooling method using radial injection of cooling air directly on the rotor shaft. The injection speeds, number of nozzles, location of nozzles, total air flow rate are important factors determining the effectiveness of the radial injection cooling method. Effectiveness of the radial injection cooling was compared with traditional axial cooling method. A previously constructed test rig was modified to accommodate a new motor with higher torque and radial injection cooling. The radial injection cooling utilizes the direct air injection to the inlet region of air film from three locations at 120° from one another with each location having three axially separated holes. In axial cooling, a certain axial pressure gradient is applied across the bearing to induce axial cooling air through bump foil channels. For the comparison of the two methods, the same amount of cooling air flow rate was used for both axial cooling and radial injection. Cooling air flow rate was

Narrowing beam-walking is a clinically feasible approach for assessing balance ability in lower-limb prosthesis users.

Science.gov (United States)

Sawers, Andrew; Hafner, Brian J

2018-05-08

Challenging clinical balance tests are needed to expose balance deficits in lower-limb prost-hesis users. This study examined whether narrowing beam-walking could overcome conceptual and practical limitations identified in fixed-width beam-walking. Cross-sectional. Unilateral lower-limb prosthesis users. Participants walked 10 times along a low, narrowing beam. Performance was quantified using the normalized distance walked. Heuristic rules were applied to determine whether the narrowing beam task was "too easy," "too hard," or "appropriately challenging" for each participant. Linear regression and Bland-Altman plots were used to determine whether combinations of the first 5 trials could predict participants' stable beam-walking performance. Forty unilateral lower-limb prosthesis users participated. Narrowing beam-walking was appropriately challenging for 98% of participants. Performance stabilized for 93% of participants within 5 trials, while 62% were stable across all trials. The mean of trials 3-5 accurately predicted stable performance. A clinical narrowing beam-walking test is likely to challenge a range of lower-limb prosthesis users, have minimal administrative burden, and exhibit no floor or ceiling effects. Narrowing beam-walking is therefore a clinically viable method to evaluate lower-limb prosthesis users' balance ability, but requires psychometric testing before it is used to assess fall risk.

The effects of indwelling voice prosthesis on the quality of life, depressive symptoms, and self-esteem in patients with total laryngectomy.

Science.gov (United States)

Polat, Beldan; Orhan, Kadir Serkan; Kesimli, Mustafa Caner; Gorgulu, Yasemin; Ulusan, Murat; Deger, Kemal

2015-11-01

This study aims to evaluate the effects of voice rehabilitation with indwelling voice prosthesis on quality of life, depression, anxiety, self-esteem, and sexual functions in laryngectomy patients. Provox-1 was applied to 30 patients who underwent total laryngectomy by opening a tracheoesophageal fistula. WHO Quality of Life-BREF, Beck Depression Inventory, Beck Anxiety Inventory, Rosenberg Self-Esteem Scale, Arizona Sexual Experience Scale forms were asked to be filled out by the patients before voice prosthesis application. These tests were asked to be filled out again 3 months later after the voice prosthesis application. Paired samples and Wilcoxon tests were used to compare before and after operation values. Indwelling voice prosthesis was found to improve quality of life, self-esteem, and sexual function (p < 0.05). Additionally, symptoms of depression and anxiety were regressed (p < 0.05). Indwelling voice prosthesis was found to especially increase the quality of life and decrease depression (p < 0.05). This study is an uncontrolled single-arm study comparing patients' psychosocial statuses pre- and post-voice prosthesis.

TOTAL ANKLE ARTHROPLASTY: BRAZILIAN EXPERIENCE WITH THE HINTEGRA PROSTHESIS.

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Nery, Caio; Fernandes, Túlio Diniz; Réssio, Cibele; Fuchs, Mauro Luiz; Godoy Santos, Alexandre Leme de; Ortiz, Rafael Trevisan

2010-01-01

Ankle arthrosis is becoming more and more common. The search for solutions that preserve joint function has led to a new generation of prosthesis with three components and more degrees of freedom. This paper presents the results achieved for ten patients treated with the HINTEGRA Prosthesis (Integra, New Deal), through collaborative action between the Foot and Ankle Groups of the Orthopedics and Traumatology divisions of Escola Paulista de Medicina, Unifesp, and the School of Medicine of the University of São Paulo (USP). The ten patients (six women and four men, aged between 29 and 66 years), underwent a surgical procedure consisting of Hintermann's technique, between January and June 2005. They were evaluated at prearranged intervals, and the data were subjected to statistical analysis. The surgery led to a significant improvement in ankle mobility. Radiological evaluation showed no signs of loosening or failure in the prosthetic components in any of the patients studied. Although the complication rate in our sample was high, it was equivalent to the rates found by other authors, and directly represents the learning curve associate with this kind of procedure. Four years after the procedure, it was found that the patients pain levels had significantly decreased, and that their functional patterns had significantly improved, with AOFAS and Hintermann scores indicating results that were excellent for 20%, good for 70% and poor for 10%. Treatment of ankle arthritis by means of total arthroplasty using the HINTEGRA prosthesis was capable of providing good results over an average observation period of four years.

Physical mechanism determining the radial electric field and its radial structure in a toroidal plasma

International Nuclear Information System (INIS)

Ida, Katsumi; Miura, Yukitoshi; Itoh, Sanae

1994-10-01

Radial structures of plasma rotation and radial electric field are experimentally studied in tokamak, heliotron/torsatron and stellarator devices. The perpendicular and parallel viscosities are measured. The parallel viscosity, which is dominant in determining the toroidal velocity in heliotron/torsatron and stellarator devices, is found to be neoclassical. On the other hand, the perpendicular viscosity, which is dominant in dictating the toroidal rotation in tokamaks, is anomalous. Even without external momentum input, both a plasma rotation and a radial electric field exist in tokamaks and heliotrons/torsatrons. The observed profiles of the radial electric field do not agree with the theoretical prediction based on neoclassical transport. This is mainly due to the existence of anomalous perpendicular viscosity. The shear of the radial electric field improves particle and heat transport both in bulk and edge plasma regimes of tokamaks. (author) 95 refs

[Questionnaire of the psychosocial profile of the patient with anophthalmia with indication of ocular prosthesis].

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Nicodemo, Denise; Ferreira, Lydia Masako

2006-01-01

The patient with anophthalmia may present feelings of inferiority and rejection. Knowing his/her needs and expectations contribute to a better technical intervention. To elaborate a questionnaire of the psychosocial profile of the patient with anophthalmia with indication of ocular prosthesis. An exploratory research was used to elaborate the questionnaire, by means of a guided interview followed by writing down what was said by the interviewees, who were adult patients of the Bucco-Maxillo-Facial Prosthesis Center of FOSJC - UNESP. The guided interview was made up of 14 items directly related to the future outline of the profile. Each item of the interview resulted in questions of the questionnaire, which was pretested twice before reaching its final version. The patients reported, in the exploratory research, unpleasant feelings with the loss of the eye; relationship shyness; expectations regarding surgery and prosthesis use; a wish to receive explanations and to hold their opinion about the treatment. The questionnaire of the psychosocial profile of the patient with anophthalmia with indication of ocular prosthesis is, therefore, made of 43 questions divided into 5 blocks in order to aid the comprehension of the inquired aspects and to facilitate both the computation of data and discussion, and also to improve the selection of questions according to the objective of the researcher or professional. It was concluded that the questionnaire was viable, can be used in full or by selecting blocks and provide a panorama of the patient's history related to the problem he/she faces, from the loss of the ocular globe to the confection of the prosthesis.

Use of digital technologies for nasal prosthesis manufacturing.

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Palousek, David; Rosicky, Jiri; Koutny, Daniel

2014-04-01

Digital technology is becoming more accessible for common use in medical applications; however, their expansion in prosthetic and orthotic laboratories is not large because of the persistent image of difficult applicability to real patients. This article aims to offer real example in the area of human facial prostheses. This article describes the utilization of optical digitization, computational modelling, rapid prototyping, mould fabrication and manufacturing of a nasal silicone prosthesis. This technical note defines the key points of the methodology and aspires to contribute to the introduction of a certified manufacturing procedure. The results show that the used technologies reduce the manufacturing time, reflect patient's requirements and allow the manufacture of high-quality prostheses for missing facial asymmetric parts. The methodology provides a good position for further development issues and is usable for clinical practice. Clinical relevance Utilization of digital technologies in facial prosthesis manufacturing process can be a good contribution for higher patient comfort and higher production efficiency but with higher initial investment and demands for experience with software tools.

Maxillary Implant-Supported Fixed Prosthesis: A Survey of Reviews and Key Variables for Treatment Planning.

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Gallucci, German O; Avrampou, Marianna; Taylor, James C; Elpers, Julie; Thalji, Ghadeer; Cooper, Lyndon F

2016-01-01

This review was conducted to provide information to support the establishment of clinical guidelines for the treatment of maxillary edentulism using implant-supported fixed dental prostheses. Initial efforts were directed toward a systematic review with a defined PICO question: "For maxillary edentulous patients with dental implants treated using a fixed prosthesis, what is the impact of prosthesis design on prosthesis survival and complications?" Following a title search of more than 3,000 titles identified by electronic search of PubMed, 180 articles were identified that addressed the clinical evaluation of maxillary dental implant prostheses. The broad methodologic heterogeneity and clinical variation among reports precluded this approach for a systematic review. The information was extracted using a standardized extraction table by two pairs of investigators, and the reported outcomes were then summarized according to reported outcomes for implant prostheses supported by four, six, or eight implants using unitary or segmented prostheses. This review indicated that high prosthetic survival is observed using all approaches. The advantages of using fewer implants and a unitary prosthesis are revealed in the surgical phases, and complications commonly involve the fracture or detachment of acrylic teeth and reduced access for proper oral hygiene and related biologic complications. Using six implants typically involved grafting of posterior regions with advantages of reduced cantilevers and redundancy of implant support. Reduced prosthesis survival in these cases was associated with poor implant distribution. Segmented prostheses supported by six or more implants offered greater prosthetic survival, perhaps due to posterior implant placement. Advantages of a segmented prosthesis included pragmatic issues of accommodating divergent implants, attaining passive fit, combining prosthetic materials, and relative simplicity of repair. The existing literature demonstrated

HyPro: A Multi-DoF Hybrid-Powered Transradial Robotic Prosthesis

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C. L. Semasinghe

2018-01-01

Full Text Available This paper proposes a multi-DoF hybrid-powered transradial robotic prosthesis, named HyPro. The HyPro consists of two prosthetic units: hand and wrist that can achieve five grasping patterns such as power grasp, tip grasp, lateral grasp, hook grasp, and index point. It is an underactuated device with 15 degrees of freedom. A hybrid powering concept is proposed and implemented on hand unit of HyPro where the key focus is on restoration of grasp functions of biological hand. A novel underactuated mechanism is introduced to achieve the required hand preshaping for a given grasping pattern using electric power in the pregrasp stage and body power is used in grasp stage to execute the final grasping action with the selected fingers. Unlike existing hybrid prostheses where each of the joints is separately controlled by either electric or body power, the proposed prosthesis is capable of delivering grasping power in combination. The wrist unit of HyPro is designed and developed to achieve flexion-extension and supination-pronation using electric power. Experiments were carried out to evaluate the functionality and performance of the proposed hybrid-powered robotic prosthesis. The results verified the potential of HyPro to perform intended grasping patterns effectively and efficiently.

Frequent complications and severe bone loss associated with the repiphysis expandable distal femoral prosthesis.

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Cipriano, Cara A; Gruzinova, Irina S; Frank, Rachel M; Gitelis, Steven; Virkus, Walter W

2015-03-01

The treatment of choice for distal femur malignancies in skeletally immature patients remains controversial. An expandable endoprosthesis device (Repiphysis Limb Salvage System; Wright Medical Technology, Arlington, TN, USA) allows for limb preservation and noninvasive lengthening but has been associated with significant complications; however, the extent and implications of bone loss associated with this implant have not been reported. Our goals were to report (1) the 2-year minimum clinical outcomes after placement of the Repiphysis expandable prosthesis for pediatric distal femur malignancies; (2) the complications associated with this prosthesis; (3) the failure rate of this prosthesis; and (4) the revision alternatives available for salvage procedures. Between 2002 and 2010, one surgeon (SG) treated all skeletally immature patients (mean age, 10.1 years; range, 4.7-13.6 years) with distal femoral osteosarcoma using a Repiphysis expandable prosthesis. Of the 12 patients who met these criteria, two were excluded for death from disease before 2 years, and mean followup for the remaining 10 was 72 months (range, 26-119 months). Medical records were retrospectively reviewed for complications and clinical outcomes, as assessed by the Musculoskeletal Tumor Society (MSTS) scoring system. Radiographs at final followup were reviewed for bone loss and analyzed by the two senior authors (SG, WWV) to determine reconstruction options available for future revisions. MSTS scores averaged 67%, and we observed 37 implant-related complications requiring a total of 15 reoperations. Six patients underwent implant revisions with aseptic loosening being the predominant mode of failure; ultimately, four of these were converted to adult modular oncology prostheses, and two underwent total femoral replacements. Bone loss in this series was severe in terms of femoral length, cortical thinning, and metadiaphyseal compromise, and most patients will not have sufficient bone stock to permit

An anthropomorphic transhumeral prosthesis socket developed based on an oscillometric pump and controlled by force-sensitive resistor pressure signals.

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Razak, N A Abd; Gholizadeh, H; Hasnan, N; Osman, N A Abu; Fadzil, S S Mohd; Hashim, N A

2017-02-01

While considering the importance of the interface between amputees and prosthesis sockets, we study an anthropomorphic prosthesis socket whose size can be dynamically changed according to the requirements of the residual limb. First, we introduce the structure and function of the anthropomorphic prosthesis socket. Second, we study the dynamic model of the prosthesis system and analyze the dynamic characteristics of the prosthesis socket system, the inputs of an oscillometric pump, and the control mechanism of force-sensitive resistor (FSR) pressure signals. Experiments on 10 healthy subjects using the designed system yield an average detection result between 102 and 112 kPa for the FSR pressure sensor and 39 and 41 kPa for the oscillometric pump. Results show the function of the FSR pressure signal in maintaining the contact pressure between the sockets and the residual limb. The potential development of an auto-adjusted socket that uses an oscillometric pump system will provide prosthetic sockets with controllable contact pressure at the residual limb. Moreover, this development is an attractive research area for researchers involved in rehabilitation engineering, prosthetics, and orthotics.

Magnesium-Based Absorbable Metal Screws for Intra-Articular Fracture Fixation

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Roland Biber

2016-01-01

Full Text Available MAGNEZIX® (Syntellix AG, Hanover, Germany is a biodegradable magnesium-based alloy (MgYREZr which is currently used to manufacture bioabsorbable compression screws. To date, there are very few studies reporting on a limited number of elective foot surgeries using this innovative implant. This case report describes the application of this screw for osteochondral fracture fixation at the humeral capitulum next to a loose radial head prosthesis, which was revised at the same time. The clinical course was uneventful. Degradation of the magnesium alloy did not interfere with fracture healing. Showing an excellent clinical result and free range-of-motion, the contour of the implant was still visible in a one-year follow-up.

Validation of the Narrowing Beam Walking Test in Lower Limb Prosthesis Users.

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Sawers, Andrew; Hafner, Brian

2018-04-11

To evaluate the content, construct, and discriminant validity of the Narrowing Beam Walking Test (NBWT), a performance-based balance test for lower limb prosthesis users. Cross-sectional study. Research laboratory and prosthetics clinic. Unilateral transtibial and transfemoral prosthesis users (N=40). Not applicable. Content validity was examined by quantifying the percentage of participants receiving maximum or minimum scores (ie, ceiling and floor effects). Convergent construct validity was examined using correlations between participants' NBWT scores and scores or times on existing clinical balance tests regularly administered to lower limb prosthesis users. Known-groups construct validity was examined by comparing NBWT scores between groups of participants with different fall histories, amputation levels, amputation etiologies, and functional levels. Discriminant validity was evaluated by analyzing the area under each test's receiver operating characteristic (ROC) curve. No minimum or maximum scores were recorded on the NBWT. NBWT scores demonstrated strong correlations (ρ=.70‒.85) with scores/times on performance-based balance tests (timed Up and Go test, Four Square Step Test, and Berg Balance Scale) and a moderate correlation (ρ=.49) with the self-report Activities-specific Balance Confidence scale. NBWT performance was significantly lower among participants with a history of falls (P=.003), transfemoral amputation (P=.011), and a lower mobility level (P.50 (ie, chance). The results provide strong evidence of content, construct, and discriminant validity for the NBWT as a performance-based test of balance ability. The evidence supports its use to assess balance impairments and fall risk in unilateral transtibial and transfemoral prosthesis users. Copyright © 2018 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

The Effect of Breast Reconstruction Prosthesis on Photon Dose Distribution in Breast Cancer Radiotherapy

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fatemeh sari

2017-12-01

Full Text Available Introduction: Siliconeprosthetic implants are commonlyutilizedfor tissue replacement and breast augmentation after mastectomy. On the other hand, some patients require adjuvant radiotherapy in order to preventlocal-regional recurrence and increment ofthe overall survival. In case of recurrence, the radiation oncologist might have to irradiate the prosthesis.The aim of this study was to evaluate the effect of silicone prosthesis on photon dose distribution in breast radiotherapy. Materials and Methods: The experimental dosimetry was performed using theprosthetic breast phantom and the female-equivalent mathematical chest phantom. A Computerized Tomographybased treatment planning was performedusing a phantom and by CorePlan Treatment Planning System (TPS. For measuring the absorbed dose, thermoluminescent dosimeter(TLD chips (GR-207A were used. Multiple irradiations were completed for all the TLD positions, and the dose absorbed by the TLDs was read by a lighttelemetry (LTM reader. Results: Statistical comparisons were performed between the absorbed dosesassessed by the TLDs and the TPS calculations forthe same sites. Our initial resultsdemonstratedanacceptable agreement (P=0.064 between the treatment planning data and the measurements. The mean difference between the TPS and TLD resultswas 1.99%.The obtained findings showed that radiotherapy is compatible withsilicone gel prosthesis. Conclusion: It could be concludedthat the siliconbreast prosthesis has no clinicallysignificant effectondistribution of a 6 MV photon beam for reconstructed breasts.

Radial retinotomy in the macula.

Science.gov (United States)

Bovino, J A; Marcus, D F

1984-01-01

Radial retinotomy is an operative procedure usually performed in the peripheral or equatorial retina. To facilitate retinal attachment, the authors used intraocular scissors to perform radial retinotomy in the macula of two patients during vitrectomy surgery. In the first patient, a retinal detachment complicated by periretinal proliferation and macula hole formation was successfully reoperated with the aid of three radial cuts in the retina at the edges of the macular hole. In the second patient, an intraoperative retinal tear in the macula during diabetic vitrectomy was also successfully repaired with the aid of radial retinotomy. In both patients, retinotomy in the macula was required because epiretinal membranes, which could not be easily delaminated, were hindering retinal reattachment.

Simulation of the filtration mechanism of hyaluronic acid in total knee prosthesis

International Nuclear Information System (INIS)

Paolo, J Di; Berli, M E; Campana, D M; Ubal, S; Cardenes, L D

2007-01-01

Polyethylene (UHMWPE) wear in current knee prosthesis causes prosthesis loosening after no more than 15 years. In this work, a steady state one-dimensional lubrication model with non- Newtonian fluid, porous elastic layer on tibial component, ultra-filtration mechanism of fluid and some features of the surface roughness is studied through a numerical technique based on the Finite Element Method. The results show that the UHMWPE stiffness makes difficult the lubrication mechanism of the artificial joint and promotes abrasive and fatigue wear. Nevertheless, the use of compliant porous materials on the tibial component could reduce friction and wear. Moreover, the ultra-filtration mechanism promotes efficiency on the joint

Narrowing beam-walking is a clinically feasible approach for assessing balance ability in lower-limb prosthesis users

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Andrew Sawers

2018-03-01

Full Text Available Objective: Challenging clinical balance tests are needed to expose balance deficits in lower-limb prost-hesis users. This study examined whether narrowing beam-walking could overcome conceptual and practical limitations identified in fixed-width beam-walking. Design: Cross-sectional. Participants: Unilateral lower-limb prosthesis users. Methods: Participants walked 10 times along a low, narrowing beam. Performance was quantified using the normalized distance walked. Heuristic rules were applied to determine whether the narrowing beam task was “too easy,” “too hard,” or “appropriately challenging” for each participant. Linear regression and Bland-Altman plots were used to determine whether combinations of the first 5 trials could predict participants’ stable beam-walking performance. Results: Forty unilateral lower-limb prosthesis users participated. Narrowing beam-walking was appropriately challenging for 98% of participants. Performance stabilized for 93% of participants within 5 trials, while 62% were stable across all trials. The mean of trials 3–5 accurately predicted stable performance. Conclusion: A clinical narrowing beam-walking test is likely to challenge a range of lower-limb prosthesis users, have minimal administrative burden, and exhibit no floor or ceiling effects. Narrowing beam-walking is therefore a clinically viable method to evaluate lower-limb prosthesis users’ balance ability, but requires psychometric testing before it is used to assess fall risk.

Inflatable penile prosthesis implant length with baseline characteristic correlations: preliminary analysis of the PROPPER study.

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Bennett, Nelson; Henry, Gerard; Karpman, Edward; Brant, William; Jones, LeRoy; Khera, Mohit; Kohler, Tobias; Christine, Brian; Rhee, Eugene; Kansas, Bryan; Bella, Anthony J

2017-12-01

"Prospective Registry of Outcomes with Penile Prosthesis for Erectile Restoration" (PROPPER) is a large, multi-institutional, prospective clinical study to collect, analyze, and report real-world outcomes for men implanted with penile prosthetic devices. We prospectively correlated co-morbid conditions and demographic data with implanted penile prosthesis size to enable clinicians to better predict implanted penis size following penile implantation. We present many new data points for the first time in the literature and postulate that radical prostatectomy (RP) is negatively correlated with penile corporal length. Patient demographics, medical history, baseline characteristics and surgical details were compiled prospectively. Pearson correlation coefficient was generated for the correlation between demographic, etiology of ED, duration of ED, co-morbid conditions, pre-operative penile length (flaccid and stretched) and length of implanted penile prosthesis. Multivariate analysis was performed to define predictors of implanted prosthesis length. From June 2011 to June 2017, 1,135 men underwent primary implantation of penile prosthesis at a total of 11 study sites. Malleable (Spectra), 2-piece Ambicor, and 3-piece AMS 700 CX/LGX were included in the analysis. The most common patient comorbidities were CV disease (26.1%), DM (11.1%), and PD (12.4%). Primary etiology of ED: RP (27.4%), DM (20.3%), CVD (18.0%), PD (10.3%), and Priapism (1.4%), others (22.6%). Mean duration of ED is 6.2¡À4.1 years. Implant length was weakly negatively correlated with White/Caucasian (r=-0.18; Pprosthesis length is negatively correlated with some ethnic groups, prostatectomy, and incontinence. Positive correlates include CV disease, preoperative stretched penile length, and flaccid penile length.

Aortic valve prosthesis-patient mismatch and exercise capacity in adult patients with congenital heart disease.

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van Slooten, Ymkje J; van Melle, Joost P; Freling, Hendrik G; Bouma, Berto J; van Dijk, Arie Pj; Jongbloed, Monique Rm; Post, Martijn C; Sieswerda, Gertjan T; Huis In 't Veld, Anna; Ebels, Tjark; Voors, Adriaan A; Pieper, Petronella G

2016-01-01

To report the prevalence of aortic valve prosthesis-patient mismatch (PPM) in an adult population with congenital heart disease (CHD) and its impact on exercise capacity. Adults with congenital heart disease (ACHD) with a history of aortic valve replacement may outgrow their prosthesis later in life. However, the prevalence and clinical consequences of aortic PPM in ACHD are presently unknown. From the national Dutch Congenital Corvitia (CONCOR) registry, we identified 207 ACHD with an aortic valve prosthesis for this cross-sectional cohort study. Severe PPM was defined as an indexed effective orifice area ≤0.65 cm2/m2 and moderate PPM as an indexed orifice area ≤0.85 cm2/m2 measured using echocardiography. Exercise capacity was reported as percentage of predicted exercise capacity (PPEC). Of the 207 patients, 68% was male, 71% had a mechanical prosthesis and mean age at inclusion was 43.9 years ±11.4. The prevalence of PPM was 42%, comprising 23% severe PPM and 19% moderate PPM. Prevalence of PPM was higher in patients with mechanical prostheses (pHeart Association (NYHA) class remained stable in most patients. PPM showed no significant effect on death or hospitalisation during follow-up (p=0.218). In this study we report a high prevalence (42%) of PPM in ACHD with an aortic valve prosthesis and an independent association of PPM with diminished exercise capacity. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Radial cracks and fracture mechanism of radially oriented ring 2:17 type SmCo magnets

International Nuclear Information System (INIS)

Tian Jianjun; Pan Dean; Zhou Hao; Yin Fuzheng; Tao Siwu; Zhang Shengen; Qu Xuanhui

2009-01-01

Radially oriented ring 2:17 type SmCo magnets have different microstructure in the radial direction (easy magnetization) and axial direction (hard magnetization). The structure of the cross-section in radial direction is close-packed atomic plane, which shows cellular microstructure. The microstructure of the cross-section in axial direction consists of a mixture of rhombic microstructure and parallel lamella phases. So the magnets have obvious anisotropy of thermal expansion in different directions. The difference of the thermal expansion coefficients reaches the maximum value at 830-860 deg. C, which leads to radial cracks during quenching. The magnets have high brittlement because there are fewer slip systems in crystal structure. The fracture is brittle cleavage fracture.

Cyclooxygenase-2 inhibitors and knee prosthesis surgery

OpenAIRE

Meunier, Andreas

2008-01-01

Adverse effects of cyclooxygenase (COX) inhibitors on bone healing have previously been demonstrated in diaphyseal fracture models in animals. In spite of that, they are widely used as postoperative analgesics in orthopaedic surgery. After joint replacement, a bone repair process starts at the interface between bone and cement. If this process is disturbed, the prosthesis may never become rigidly fixed to the bone, leading to migration and with time loosening. This thesis investigates the eff...

[Directions for reoperation of patients with Björk-Shiley convexo-concave valve prosthesis, based on long-term experience].

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Yamaki, F; Nakano, K; Endo, M; Hashimoto, A; Koyanagi, H

1994-02-01

Although a high incidence of strut fracture of the Björk-Shiley convexo-concave (C-C) valve prosthesis has been reported, it is still controversial whether the prosthesis functioning normally should be replaced electively. To clarify our policy for this issue, we reviewed 28 patients who had undergone mitral valve replacement with a C-C valve prosthesis, and evaluated long-term results according to STS guidelines. The incidence of valve-related complications expressed as % patient-year were; structural deterioration 0.30, nonstructural dysfunction 0.30, thromboembolism 1.20. There were no thrombosed valves, anticoagulant-related hemorrhage or prosthetic valve endocarditis. The actuarial free rate after valve replacement with the C-C at 10 years, constructed by the Kaplan-Meier method, were compared with those with St. Jude Medical (SJM) valve prosthesis. (1) Actuarial survival: 77.9 vs 87.3 (NS), (2) Reoperation-free: 91.6 vs 98.0 (p valve-related complications: 71.2 vs 77.7 (NS). The long-term results with the C-C were compatible to those with a SJM valve prosthesis. However, if a strut fracture occurs, it is very difficult to save the patient's life. The hospital mortality of re-replacement of valve prosthesis during the last 10 years, at our institute, was 2.6%, which is almost equal to the cumulative risk of strut fracture of the C-C valve after 10 years (3.0%).(ABSTRACT TRUNCATED AT 250 WORDS)

Above-knee prosthesis design based on fatigue life using finite element method and design of experiment.

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Phanphet, Suwattanarwong; Dechjarern, Surangsee; Jomjanyong, Sermkiat

2017-05-01

The main objective of this work is to improve the standard of the existing design of knee prosthesis developed by Thailand's Prostheses Foundation of Her Royal Highness The Princess Mother. The experimental structural tests, based on the ISO 10328, of the existing design showed that a few components failed due to fatigue under normal cyclic loading below the required number of cycles. The finite element (FE) simulations of structural tests on the knee prosthesis were carried out. Fatigue life predictions of knee component materials were modeled based on the Morrow's approach. The fatigue life prediction based on the FE model result was validated with the corresponding structural test and the results agreed well. The new designs of the failed components were studied using the design of experimental approach and finite element analysis of the ISO 10328 structural test of knee prostheses under two separated loading cases. Under ultimate loading, knee prosthesis peak von Mises stress must be less than the yield strength of knee component's material and the total knee deflection must be lower than 2.5mm. The fatigue life prediction of all knee components must be higher than 3,000,000 cycles under normal cyclic loading. The design parameters are the thickness of joint bars, the diameter of lower connector and the thickness of absorber-stopper. The optimized knee prosthesis design meeting all the requirements was recommended. Experimental ISO 10328 structural test of the fabricated knee prosthesis based on the optimized design confirmed the finite element prediction. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

A Preliminary Report on Combined Penoscrotal and Perineal Approach for Placement of Penile Prosthesis with Corporal Fibrosis

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John P. Brusky

2008-01-01

Full Text Available Purpose. This paper aims at describing the combined penoscrotal and perineal approach for placement of penile prosthesis in cases of severe corporal fibrosis and scarring. Materials and methods. Three patients with extensive corporal fibrosis underwent penile prosthesis placement via combined penoscrotal and perineal approach from 1997 to 2006. Follow-up ranged from 15 to 129 months. Results. All patients underwent successful implantation of semirigid penile prosthesis. There were no short- or long-term complications. Conclusions. Results on combined penoscrotal and perineal approach to penile prosthetic surgery in this preliminary series of patients suggest that it is a safe technique and increases the chance of successful outcome in the surgical management of severe corporal fibrosis.

Functional evaluation of a CAD/CAM prosthesis for immediate defect repair after total maxillectomy: a case series of 18 patients with maxillary sinus cancer.

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Jiang, Fei-Fei; Hou, Yan; Lu, Li; Ding, Xiao-Xu; Li, Wei; Yan, Ai-Hui

2015-01-01

To evaluate the facial profiles and functional recovery of 18 patients treated by a computer-aided designed/manufactured hollow obturator prosthesis (CAD/CAM prosthesis) after total maxillectomy for malignant maxillary sinus tumor. A retrospective observational study was performed to evaluate the facial profiles and functional recovery of 18 patients with T3-4a N0 M0 maxillary sinus cancer, who were treated by total maxillectomy and simultaneous implantation of a computer-aided designed/manufactured hollow obturator prosthesis (CAD/CAM prosthesis). Follow-ups were performed 1, 3, 6, and 12 months after surgery. Facial measurements, speech intelligibility, and chewing and swallowing functions were examined. Thirteen patients converted to a permanent prosthesis 6 months after surgery. Comparisons were made between patients with and without the CAD/CAM or permanent prosthesis at various times using SPSS13.0 statistical software (SPSS Inc., Chicago, IL, USA). Speech intelligibility, facial depression, and eyeball prolapse results showed improvements with prosthesis use at 1, 3, and 6 months after surgery (p maxillectomy. This surgical treatment of maxillary sinus cancer is applied rarely in China, but it has a good effect based on our observation. Simultaneous CAD/CAM prosthesis implantation after total maxillectomy can recover the facial profile, enhance the speaking, swallowing, and chewing functions, and improve the quality of life of patients. Tumor recurrence can be detected by direct observation of the postoperative maxillary cavity. This technique avoids the need for dental implants because the bottom part of the prosthesis contains a palatal plate with dentures. © 2014 Wiley Periodicals, Inc.

Veno-arterial extracorporeal membrane oxygenation as a bridge for enabling surgery in a patient under cardiogenic shock due to acute mitral prosthesis dysfunction

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María Elena Arnáiz-García

2018-04-01

Full Text Available A 52-year-old male patient, who underwent mitral replacement with a mechanical prosthesis as a child, sustained a cardiac arrest which was successfully resuscitated. Further investigation showed prosthesis malfunction with significant regurgitation in the context of multi-organ failure. In such a life-threatening condition, veno-arterial extracorporeal membrane oxygenation was considered as a rescue procedure to achieve optimisation of clinical status to allow definitive surgical treatment. An unusual complete fracture of the prosthesis was subsequently identified as the cause of acute dysfunction. Keywords: VA-ECMO, Mitral, Prosthesis, Dysfunction, Cardiogenic shock

Percutaneous closure of ductus arteriosus with the amplatzer prosthesis. The Brazilian experience

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Luiz Carlos Simões

2001-12-01

Full Text Available OBJECTIVE - To report the results of percutaneous occlusion of persistent ductus arteriosus with the Amplatzer prosthesis in 2 Brazilian cardiological centers. METHODS - From May 1998 to July 2000, 33 patients with clinical and laboratory diagnosis of persistent ductus arteriosus underwent attempts at percutaneous implantation of the Amplatzer prosthesis. The median age was 36 months (from 6 months to 38 years, and the median weight was 14kg (from 6 to 92kg. Sixteen patients (48.5% were under 2 years of age at the time of the procedure. All patients were followed up with periodical clinical and echocardiographic evaluations to assess the presence and degree of residual shunt and possible complications, such as pseudocoarctation of the aorta and left pulmonary artery stenosis. RESULTS - The minimum diameter of the arterial ducts ranged from 2.5 to 7.0mm (mean of 4.0±1.0, median of 3.9. The rate of success for implantation of the prosthesis was 100%. Femoral pulse was lost in 1 patient. The echocardiogram revealed total closure prior to hospital discharge in 30 patients, and in the follow-up visit 3 months later in the 3 remaining patients. The mean follow-up duration was 6.4±3.4 months. All patients were clinically well, asymptomatic, and did not need medication. No patient had narrowing of the left pulmonary artery or of the aorta. No early or late embolic events occurred, nor did infectious endarteritis. A new hospital admission was not required for any patient. CONCLUSION - The Amplatzer prosthesis for persistent ductus arteriosus is safe and highly effective for occlusion of ductus arteriosus of varied diameters, including large ones in small symptomatic infants.

Common spatial pattern combined with kernel linear discriminate and generalized radial basis function for motor imagery-based brain computer interface applications

Science.gov (United States)

Hekmatmanesh, Amin; Jamaloo, Fatemeh; Wu, Huapeng; Handroos, Heikki; Kilpeläinen, Asko

2018-04-01

Brain Computer Interface (BCI) can be a challenge for developing of robotic, prosthesis and human-controlled systems. This work focuses on the implementation of a common spatial pattern (CSP) base algorithm to detect event related desynchronization patterns. Utilizing famous previous work in this area, features are extracted by filter bank with common spatial pattern (FBCSP) method, and then weighted by a sensitive learning vector quantization (SLVQ) algorithm. In the current work, application of the radial basis function (RBF) as a mapping kernel of linear discriminant analysis (KLDA) method on the weighted features, allows the transfer of data into a higher dimension for more discriminated data scattering by RBF kernel. Afterwards, support vector machine (SVM) with generalized radial basis function (GRBF) kernel is employed to improve the efficiency and robustness of the classification. Averagely, 89.60% accuracy and 74.19% robustness are achieved. BCI Competition III, Iva data set is used to evaluate the algorithm for detecting right hand and foot imagery movement patterns. Results show that combination of KLDA with SVM-GRBF classifier makes 8.9% and 14.19% improvements in accuracy and robustness, respectively. For all the subjects, it is concluded that mapping the CSP features into a higher dimension by RBF and utilization GRBF as a kernel of SVM, improve the accuracy and reliability of the proposed method.

Rehabilitation with ear prosthesis linked to osseointegrated implants.

Science.gov (United States)

Goiato, Marcelo C; dos Santos, Daniela M; Haddad, Marcela F; Moreno, Amália

2012-06-01

The absence of an ear, which can be the result of a congenital malformation, surgical tumour resection or traumatic injury, is a significant aesthetic problem. Attachment of ear prostheses with adhesives can cause local irritation for the wearer and affect the colour of the prostheses. Use of implants in craniofacial reconstruction can improve the retention and stability of prostheses giving to patient greater comfort and security relative to adhesive attachment. The aim of this report was to present a clinical case of a mutilated patient who was rehabilitated by means of installing an ear prosthesis fixed through osseointegrated implants. The patient had two implants installed in the mastoid region that were linked by a bar, and a clip-type system was used. The ear prosthesis was constructed from medical-use silicone, pigmented to match the patient's skin colour and linked to the retention system. The patient's rehabilitation was satisfactory from both a functional and an aesthetic point of view, making it possible for the patient to return to a normal social life and regain lost self-esteem. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

Hearing improvement after stapedotomy using teflon loop prosthesis

International Nuclear Information System (INIS)

Ahmed, S.; Raza, N.

2006-01-01

To assess hearing improvement after stapedotomy for otosclerosis using teflon loop prosthesis. Thirty diagnosed cases of otosclerosis were included in the study. Ear with greater air-bone gap was selected and stapedotomy was done using teflon loop prosthesis (size 4 - 4.5 mm). Mild vertigo occurred during immediate postoperative period, which subsided with Inj. Prochlorperazine. Patients were followed-up postsurgically at one month, two months, four months, six months and one year and postoperative air-bone gap was calculated. Out of 30 cases, there were 24 males and 06 females. The age ranged from 18 to 50 years. Twenty-one (70%) patients had bilateral hearing loss and 09 (30%) had tinnitis also. Pre-operative audiograms showed conductive deafness. Carhart's notch was present in 10 (33.3%) cases. Tympanogram revealed loss of stapedial reflex. Postoperatively good hearing improvement was seen in 56.7% (postoperative air-bone gap closure upto 10 dB), fair improvement in 30% (postoperative air bone gap closure from 11 to 20 dB) and poor results in 10% (postoperative air-bone gap more than 21 dB) cases. One patient developed dead ear. (author)

The clinical relevance of advanced artificial feedback in the control of a multi-functional myoelectric prosthesis

DEFF Research Database (Denmark)

Markovic, Marko; Schweisfurth, Meike A.; Engels, Leonard F.

2018-01-01

. Nonetheless, the benefits of feedback in prosthetics are still debated. The lack of consensus is likely due to the complex nature of sensory feedback during prosthesis control, so that its effectiveness depends on multiple factors (e.g., task complexity, user learning). METHODS: We evaluated the impact...... of these factors with a longitudinal assessment in six amputee subjects, using a clinical setup (socket, embedded control) and a range of tasks (box and blocks, block turn, clothespin and cups relocation). To provide feedback, we have proposed a novel vibrotactile stimulation scheme capable of transmitting...... multiple variables from a multifunction prosthesis. The subjects wore a bracelet with four by two uniformly placed vibro-tactors providing information on contact, prosthesis state (active function), and grasping force. The subjects also completed a questionnaire for the subjective evaluation...

Developing an Ear Prosthesis Fabricated in Polyvinylidene Fluoride by a 3D Printer with Sensory Intrinsic Properties of Pressure and Temperature

Directory of Open Access Journals (Sweden)

Ernesto Suaste-Gómez

2016-03-01

Full Text Available An ear prosthesis was designed in 3D computer graphics software and fabricated using a 3D printing process of polyvinylidene fluoride (PVDF for use as a hearing aid. In addition, the prosthesis response to pressure and temperature was observed. Pyroelectric and piezoelectric properties of this ear prosthesis were investigated using an astable multivibrator circuit, as changes in PVDF permittivity were observed according to variations of pressure and temperature. The results show that this prosthesis is reliable for use under different conditions of pressure (0 Pa to 16,350 Pa and temperature (2 °C to 90 °C. The experimental results show an almost linear and inversely proportional behavior between the stimuli of pressure and temperature with the frequency response. This 3D-printed ear prosthesis is a promising tool and has a great potentiality in the biomedical engineering field because of its ability to generate an electrical potential proportional to pressure and temperature, and it is the first time that such a device has been processed by the additive manufacturing process (3D printing. More work needs to be carried out to improve the performance, such as electrical stimulation of the nervous system, thereby extending the purpose of a prosthesis to the area of sensory perception.

Multi-body simulation of various falling scenarios for determining resulting loads at the prosthesis interface of transfemoral amputees with osseointegrated fixation.

Science.gov (United States)

Welke, Bastian; Schwarze, Michael; Hurschler, Christof; Calliess, Tilman; Seehaus, Frank

2013-07-01

Conventionally, transfemoral amputees are treated with a shaft prosthesis fitted over the residual limb. To improve the quality of life of such patients, in particular those with complications relating to conventional attachment (e.g., skin irritation, stump ulcers, and poor motor-control with short stumps), osseointegrated prosthesis fixation implants have been developed and implanted in a limited population of patients. To assess possible damage to the implant/prosthesis during falling scenarios, the loads in high-risk situations were estimated using a multi-body simulation of motion. Five falling scenarios were identified and performed by healthy volunteer wearing safety equipment. Kinematic data and ground reaction forces were captured as input for the inverse-dynamics-based simulations, from which the forces and moments at a typical implant-prosthesis interface location were computed. The estimated peak loads in all five scenarios were of a magnitude that could lead to bone fracture. The largest peak force observed was 3274 ± 519 N, with an associated resultant moment of 176 ± 55 Nm on the prosthesis-implant interface. A typical femur is prone to fracture under this load, thus illustrating the need for a safety-release element in osseointegrated prosthesis fixation. Copyright © 2013 Orthopaedic Research Society.

Developing an Ear Prosthesis Fabricated in Polyvinylidene Fluoride by a 3D Printer with Sensory Intrinsic Properties of Pressure and Temperature.

Science.gov (United States)

Suaste-Gómez, Ernesto; Rodríguez-Roldán, Grissel; Reyes-Cruz, Héctor; Terán-Jiménez, Omar

2016-03-04

An ear prosthesis was designed in 3D computer graphics software and fabricated using a 3D printing process of polyvinylidene fluoride (PVDF) for use as a hearing aid. In addition, the prosthesis response to pressure and temperature was observed. Pyroelectric and piezoelectric properties of this ear prosthesis were investigated using an astable multivibrator circuit, as changes in PVDF permittivity were observed according to variations of pressure and temperature. The results show that this prosthesis is reliable for use under different conditions of pressure (0 Pa to 16,350 Pa) and temperature (2 °C to 90 °C). The experimental results show an almost linear and inversely proportional behavior between the stimuli of pressure and temperature with the frequency response. This 3D-printed ear prosthesis is a promising tool and has a great potentiality in the biomedical engineering field because of its ability to generate an electrical potential proportional to pressure and temperature, and it is the first time that such a device has been processed by the additive manufacturing process (3D printing). More work needs to be carried out to improve the performance, such as electrical stimulation of the nervous system, thereby extending the purpose of a prosthesis to the area of sensory perception.

Prosthesis use in adult acquired major upper-limb amputees: patterns of wear, prosthetic skills and the actual use of prostheses in activities of daily life.

Science.gov (United States)

Østlie, Kristin; Lesjø, Ingrid Marie; Franklin, Rosemary Joy; Garfelt, Beate; Skjeldal, Ola Hunsbeth; Magnus, Per

2012-11-01

To describe patterns of prosthesis wear and perceived prosthetic usefulness in adult acquired upper-limb amputees (ULAs). To describe prosthetic skills in activities of daily life (ADL) and the actual use of prostheses in the performance of ADL tasks. To estimate the influence of prosthetic skills on actual prosthesis use and the influence of background factors on prosthetic skills and actual prosthesis use. Cross-sectional study analysing population-based questionnaire data (n = 224) and data from interviews and clinical testing in a referred/convenience sample of prosthesis-wearing ULAs (n = 50). Effects were analysed using linear regression. 80.8% wore prostheses. 90.3% reported their most worn prosthesis as useful. Prosthetic usefulness profiles varied with prosthetic type. Despite demonstrating good prosthetic skills, the amputees reported actual prosthesis use in only about half of the ADL tasks performed in everyday life. In unilateral amputees, increased actual use was associated with sufficient prosthetic training and with the use of myoelectric vs cosmetic prostheses, regardless of amputation level. Prosthetic skills did not affect actual prosthesis use. No background factors showed significant effect on prosthetic skills. Most major ULAs wear prostheses. Individualised prosthetic training and fitting of myoelectric rather than passive prostheses may increase actual prosthesis use in ADL.

Verge of Collapse: The Pros/thesis of Art Research

Science.gov (United States)

Garoian, Charles R.

2008-01-01

This article explores "prosthesis" as a metaphor of embodiment in art-based research to challenge the utopian myth of wholeness and normality in art and the human body. Bearing in mind the correspondences between amputated bodies and the cultural dislocations of art, I propose "prosthetic epistemology" and "prosthetic ontology" as embodied knowing…

Prosthetic Rehabilitation of a Patient with Ocular Defect using Semi-customized Prosthesis: A Case Report

OpenAIRE

Putanikar, Nagaraj Y.; Patil, Anandkumar G.; Shetty, Pavithra K.; Nagaral, Suresh; Mithaiwala, Hatimali I.

2015-01-01

Severe physical and psychological distress occurs due to disfigurement caused by loss of eye. Ocular prosthesis is the only mode of rehabilitation for the missing eye. There are different materials and techniques used for the fabrication of the same. Resin proved to be the better among the available materials. Either using the stock eye or using customized ocular prosthesis has their own advantages and disadvantages. Through our clinical report, we have fabricated a semi-customized ocular pro...

SU-E-J-230: Effect of Metal Hip Prosthesis On the Accuracy of Electromagnetic Localization and Tracking

International Nuclear Information System (INIS)

Butler, W; Merrick, G; Kurko, B; Bittner, N

2014-01-01

Purpose: To quantify the effect of metal hip prosthesis on the ability to track and localize electromagnetic transponders. Methods: Three Calypso transponders were implanted into two prostate phantoms. The geometric center of the transponders were identified on computed tomography and set as the isocenter. With the phantom stationary on the treatment table and the tracking array 14-cm above the isocenter, data was acquired by the Calypso system at 10 Hz to establish the uncertainty in measurements. Transponder positional data was acquired with unilateral hip prostheses of different metallic compositions and then with bilateral hips placed at variable separation from the phantom. Results: Regardless of hip prosthesis composition, the average vector displacement in the presence of a unilateral prosthesis was < 0.5 mm. The greatest contribution to overall vector displacement occurred in the lateral dimension. With bilateral hip prosthesis, the average vector displacement was 0.3 mm. The displacement in the lateral dimension was markedly reduced compared with a unilateral hip, suggesting that there was a countervailing effect with bilateral hip prosthesis. The greatest average vector displacement was 0.6 mm and occurred when bilateral hip prostheses were placed within 4 cm of the detector array. Conclusion: Unilateral and bilateral hip prostheses did not have any meaningful effect on the ability to accurately track electromagnetic transponders implanted in a prostate phantom. At clinically realistic distances between the hip and detection array, the average tracking error is negligible

Perceived radial translation during centrifugation

NARCIS (Netherlands)

Bos, J.E.; Correia Grácio, B.J.

2015-01-01

BACKGROUND: Linear acceleration generally gives rise to translation perception. Centripetal acceleration during centrifugation, however, has never been reported giving rise to a radial, inward translation perception. OBJECTIVE: To study whether centrifugation can induce a radial translation

Control of dental prosthesis system with microcontroller.

Science.gov (United States)

Kapidere, M; Müldür, S; Güler, I

2000-04-01

In this study, a microcontroller-based electronic circuit was designed and implemented for dental prosthesis curing system. Heater, compressor and valve were controlled by 8-bit PIC16C64 microcontroller which is programmed using MPASM package. The temperature and time were controlled automatically by preset values which were inputted from keyboard while the pressure was kept constant. Calibration was controlled and the working range was tested. The test results showed that the system provided a good performance.

Prosthesis-patient mismatch after transcatheter aortic valve implantation using the Edwards SAPIEN™ prosthesis.

Science.gov (United States)

Van Linden, Arnaud; Kempfert, Jörg; Blumenstein, Johannes; Rastan, Ardawan; Holzhey, David; Lehmann, Sven; Mohr, Friedrich W; Walther, Thomas

2013-08-01

Prosthesis-patient mismatch (PPM) is defined as a too small effective orifice area (EOA) of the prosthetic valve in relation to the patient's body size and has been documented to be related to adverse outcomes after conventional aortic valve replacement (AVR). Aim of this study was to analyze the incidence of PPM after transcatheter aortic valve implantation (T-AVI) using the Edwards SAPIEN prosthesis and its relation to postoperative outcome. 200 consecutive high-risk patients underwent transapical aortic valve implantation (TA-AVI) between February 2006 and January 2009 and fulfilled 1 year follow-up were included. Severe PPM was defined as indexed EOA (EOAi) <0.65 cm2/m2 and moderate PPM as EOAi = 0.65-0.85 cm2/m2, EOA was calculated from transthoracic echocardiographic (TTE) measurements using the continuity equation. Total 112 patients with sufficient postoperative TTE image quality formed the study group. EOAi increased from 0.3 ± 0.1 cm2/m2 (preoperatively) to 1.1 ± 0.4 cm2/m2 after TA-AVI (p < 0.001). According to the standard definitions, PPM was seen in 38.4% of the patients and 9.8% presented with severe PPM. The occurrence of PPM had neither an effect on clinical outcome in terms of NYHA class nor on survival. Patients with PPM had significantly higher postoperative transprosthetic gradients (mean gradient 10.4 ± 4.1 versus 7.1 ± 3.0 mm Hg, p < 0.001). Based on the in vitro EOA data obtained from pulse duplicator measurements, however, none of the patients was judged to have PPM. Transcatheter AVI provides good antegrade hemodynamic function and EOAi improves significantly. According to standardized evaluations PPM occurs after TA-AVI, but it is not associated with adverse outcomes. Thus use of the continuity equation may not adequately reflect the situation after T-AVI or the current definition of PPM is not suitable for T-AVI prostheses. Georg Thieme Verlag KG Stuttgart · New York.

A novel speech prosthesis for mandibular guidance therapy in hemimandibulectomy patient: A clinical report

Directory of Open Access Journals (Sweden)

Raghavendra Adaki

2016-01-01

Full Text Available Treating diverse maxillofacial patients poses a challenge to the maxillofacial prosthodontist. Rehabilitation of hemimandibulectomy patients must aim at restoring mastication and other functions such as intelligible speech, swallowing, and esthetics. Prosthetic methods such as palatal ramp and mandibular guiding flange reposition the deviated mandible. Such prosthesis can also be used to restore speech in case of patients with debilitating speech following surgical resection. This clinical report gives detail of a hemimandibulectomy patient provided with an interim removable dental speech prosthesis with composite resin flange for mandibular guidance therapy.

In vivo operation of the Boston 15-channel wireless subretinal visual prosthesis

Science.gov (United States)

Shire, Douglas B.; Doyle, Patrick; Kelly, Shawn K.; Gingerich, Marcus D.; Chen, Jinghua; Cogan, Stuart F.; Drohan, William A.; Mendoza, Oscar; Theogarajan, Luke; Wyatt, John; Rizzo, Joseph F.

2010-02-01

This presentation concerns the engineering development of the Boston visual prosthesis for restoring useful vision to patients blind with degenerative retinal disease. A miniaturized, hermetically-encased, 15-channel wirelessly-operated retinal prosthetic was developed for implantation and pre-clinical studies in Yucatan mini-pig animal models. The prosthesis conforms to the eye and drives a microfabricated polyimide stimulating electrode array having sputtered iridium oxide electrodes. This array is implanted into the subretinal space using a specially-designed ab externo surgical technique; the bulk of the prosthesis is on the surface of the sclera. The implanted device includes a hermetic titanium case containing a 15-channel stimulator chip; secondary power/data receiving coils surround the cornea. Long-term in vitro pulse testing was also performed on the electrodes to ensure their stability over years of operation. Assemblies were first tested in vitro to verify wireless operation of the system in biological saline using a custom RF transmitter circuit and primary coils. Stimulation pulse strength, duration and frequency were programmed wirelessly using a computer with a custom graphical user interface. Operation of the retinal implant was verified in vivo in 3 minipigs for more than three months by measuring stimulus artifacts on the eye surface using contact lens electrodes.

Reliability of MRI findings in candidates for lumbar disc prosthesis

International Nuclear Information System (INIS)

Berg, Linda; Espeland, Ansgar; Neckelmann, Gesche; Gjertsen, Oeivind; Hellum, Christian; Johnsen, Lars G.; Eide, Geir E.

2012-01-01

Limited reliability data exist for localised magnetic resonance imaging (MRI) findings relevant to planning of treatment with lumbar disc prosthesis and later outcomes. We assessed the reliability of such findings in chronic low back pain patients who were accepted candidates for disc prosthesis. On pretreatment MRI of 170 patients (mean age 41 years; 88 women), three experienced radiologists independently rated Modic changes, disc findings and facet arthropathy at L3/L4, L4/L5 and L5/S1. Two radiologists rerated 126 examinations. For each MRI finding at each disc level, agreement was analysed using the kappa statistic and differences in prevalence across observers using a fixed effects model. All findings at L3/L4 and facet arthropathy at L5/S1 had a mean prevalence <10% across observers and were not further analysed, ensuring interpretable kappa values. Overall interobserver agreement was generally moderate or good (kappa 0.40-0.77) at L4-S1 for Modic changes, nucleus pulposus signal, disc height (subjective and measured), posterior high-intensity zone (HIZ) and disc contour, and fair (kappa 0.24) at L4/L5 for facet arthropathy. Posterior HIZ at L5/S1 and severely reduced subjective disc height at L4/L5 differed up to threefold in prevalence between observers (p < 0.0001). Intraobserver agreement was mostly good or very good (kappa 0.60-1.00). In candidates for disc prosthesis, mostly moderate interobserver agreement is expected for localised MRI findings. (orig.)

Reliability of MRI findings in candidates for lumbar disc prosthesis

Energy Technology Data Exchange (ETDEWEB)

Berg, Linda; Espeland, Ansgar [Haukeland University Hospital, Department of Radiology, Bergen (Norway); University of Bergen, Section for Radiology, Department of Surgical Sciences, Bergen (Norway); Neckelmann, Gesche [Haukeland University Hospital, Department of Radiology, Bergen (Norway); Gjertsen, Oeivind [Oslo University Hospital, Department of Neuroradiology, Oslo (Norway); Hellum, Christian [Oslo University Hospital, Department of Orthopaedics, Oslo (Norway); University of Oslo, Department of Orthopaedics, Oslo (Norway); Johnsen, Lars G. [University Hospital of Trondheim, National Centre for Diseases of the Spine, Trondheim (Norway); University Hospital of Trondheim, Orthopaedic Department, Trondheim (Norway); Eide, Geir E. [Haukeland University Hospital, Centre for Clinical Research, Bergen (Norway); University of Bergen, Department of Public Health and Primary Health Care, Bergen (Norway)

2012-07-15

Limited reliability data exist for localised magnetic resonance imaging (MRI) findings relevant to planning of treatment with lumbar disc prosthesis and later outcomes. We assessed the reliability of such findings in chronic low back pain patients who were accepted candidates for disc prosthesis. On pretreatment MRI of 170 patients (mean age 41 years; 88 women), three experienced radiologists independently rated Modic changes, disc findings and facet arthropathy at L3/L4, L4/L5 and L5/S1. Two radiologists rerated 126 examinations. For each MRI finding at each disc level, agreement was analysed using the kappa statistic and differences in prevalence across observers using a fixed effects model. All findings at L3/L4 and facet arthropathy at L5/S1 had a mean prevalence <10% across observers and were not further analysed, ensuring interpretable kappa values. Overall interobserver agreement was generally moderate or good (kappa 0.40-0.77) at L4-S1 for Modic changes, nucleus pulposus signal, disc height (subjective and measured), posterior high-intensity zone (HIZ) and disc contour, and fair (kappa 0.24) at L4/L5 for facet arthropathy. Posterior HIZ at L5/S1 and severely reduced subjective disc height at L4/L5 differed up to threefold in prevalence between observers (p < 0.0001). Intraobserver agreement was mostly good or very good (kappa 0.60-1.00). In candidates for disc prosthesis, mostly moderate interobserver agreement is expected for localised MRI findings. (orig.)

Self-consistent radial sheath

International Nuclear Information System (INIS)

Hazeltine, R.D.

1988-12-01

The boundary layer arising in the radial vicinity of a tokamak limiter is examined, with special reference to the TEXT tokamak. It is shown that sheath structure depends upon the self-consistent effects of ion guiding-center orbit modification, as well as the radial variation of E /times/ B-induced toroidal rotation. Reasonable agreement with experiment is obtained from an idealized model which, however simplified, preserves such self-consistent effects. It is argued that the radial sheath, which occurs whenever confining magnetic field-lines lie in the plasma boundary surface, is an object of some intrinsic interest. It differs from the more familiar axial sheath because magnetized charges respond very differently to parallel and perpendicular electric fields. 11 refs., 1 fig

Effect of prosthesis endplate lordosis angles on L5-S1 kinematics after disc arthroplasty.

Science.gov (United States)

Tsitsopoulos, Parmenion P; Wojewnik, Bartosz; Voronov, Leonard I; Havey, Robert M; Renner, Susan M; Zelenakova, Julia; McIntosh, Braden; Carandang, Gerard; Abjornson, Celeste; Patwardhan, Avinash G

2012-06-01

We hypothesized that L5-S1 kinematics will not be affected by the lordosis distribution between the prosthesis endplates. Twelve cadaveric lumbosacral spines (51.3 ± 9.8 years) were implanted with 6° or 11° prostheses (ProDisc-L) with four combinations of superior/inferior lordosis (6°/0°, 3°/3°, 11°/0°, 3°/8°). Specimens were tested intact and after prostheses implantation with different lordosis distributions. Center of rotation (COR) and range of motion (ROM) were quantified. Six-degree lordosis prostheses (n = 7) showed no difference in flexion-extension ROM, regardless of design (6°/0° or 3°/3°) (p > 0.05). In lateral bending (LB), both designs reduced ROM (p lordosis prostheses (n = 5) showed no difference in flexion-extension ROM for either design (p > 0.05). LB ROM decreased with distributed lordosis prostheses (3°/8°) (p lordosis distribution among the two prosthesis endplates. The ProDisc-L prosthesis design where all lordosis is concentrated in the superior endplate yielded COR locations that were anterior and caudal to intact controls. The prosthesis with lordosis distributed between the two endplates yielded a COR that tended to be closer to intact. Further clinical and biomechanical studies are needed to assess the long-term impact of lordosis angle distribution on the fate of the facet joints.

[Study of satisfaction of testicular prosthesis implantation in children].

Science.gov (United States)

Martínez, Y; Millán, A; Gilabert, R; Delgado, L; De Agustín, J C

2012-01-01

Testicular absence may cause psychological trauma in children. It can be avoided by placing testicular prosthesis (TP). However there is no consensus on the optimal age of implantation. We evaluate the results of TP implantation and their complications, as well as patient and family satisfaction. This is a retrospective study of TP implanted between 2004-2010 in our center. Variables analyzed are: age, size and side, indication, surgical technique, complications and comorbidity. Telephone survey was done by a single interviewer to 50 families. general family satisfaction, characteristics of the prosthesis (size, shape, location and consistency), body image and psychological situation of the child, duration of analgesia after surgery, reoperation rate, and family advice to other parents. Statistical analysis with SPSS-18.0. 107 prostheses were placed (4 bilateral, 64 left and 35 rights) at a mean age of 70,10 +/- 58,6 months. The most common indication was cryptorchidism (48.2%). Initial inguinal approach in 69%, and simultaneous contralateral orchidopexy in 29.9%. Only one patient refused the prostheses. In 71% the mother was interviewed. Parents consider size, shape and position appropriate in 55.6%, 66.7% and 82.22% respectively. Hard consistency of TP was considered in 82.3% of the patients. Psychological problems were absent in 86.7%. Nighty five percent would be willing to replace when it was necessary. Parents would recommend the intervention to parents in the same situation in 86.7%. Testicular prosthesis avoids psychological trauma. The lack of satisfaction regarding to the small size and hardness makes necessary to replace the TP in adulthood. An open question remains whether we should consider the placement of TP in early ages, or if we should establish some indications based on a more rational communication with the family.

Rigorous patient-prosthesis matching of Perimount Magna aortic bioprosthesis.

Science.gov (United States)

Nakamura, Hiromasa; Yamaguchi, Hiroki; Takagaki, Masami; Kadowaki, Tasuku; Nakao, Tatsuya; Amano, Atsushi

2015-03-01

Severe patient-prosthesis mismatch, defined as effective orifice area index ≤0.65 cm(2) m(-2), has demonstrated poor long-term survival after aortic valve replacement. Reported rates of severe mismatch involving the Perimount Magna aortic bioprosthesis range from 4% to 20% in patients with a small annulus. Between June 2008 and August 2011, 251 patients (mean age 70.5 ± 10.2 years; mean body surface area 1.55 ± 0.19 m(2)) underwent aortic valve replacement with a Perimount Magna bioprosthesis, with or without concomitant procedures. We performed our procedure with rigorous patient-prosthesis matching to implant a valve appropriately sized to each patient, and carried out annular enlargement when a 19-mm valve did not fit. The bioprosthetic performance was evaluated by transthoracic echocardiography predischarge and at 1 and 2 years after surgery. Overall hospital mortality was 1.6%. Only 5 (2.0%) patients required annular enlargement. The mean follow-up period was 19.1 ± 10.7 months with a 98.4% completion rate. Predischarge data showed a mean effective orifice area index of 1.21 ± 0.20 cm(2) m(-2). Moderate mismatch, defined as effective orifice area index ≤0.85 cm(2) m(-2), developed in 4 (1.6%) patients. None developed severe mismatch. Data at 1 and 2 years showed only two cases of moderate mismatch; neither was severe. Rigorous patient-prosthesis matching maximized the performance of the Perimount Magna, and no severe mismatch resulted in this Japanese population of aortic valve replacement patients. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

Reliability of Free Radial Forearm Flap for Tongue Reconstruction Following Oncosurgical Resection

Directory of Open Access Journals (Sweden)

Gaurab Ranjan Chaudhuri

2015-08-01

Full Text Available Introduction Primary closure following oncosurgical resection of carcinoma tongue has been found to compromise tongue function in regards to speech and swallowing very badly. In contrast, reconstruction of tongue with free radial forearm flap following oncosurgical resection has shown promising functional outcome. Materials and Methods Thirteen patients (ten male and three female with squamous cell carcinoma involving anterior 2/3rd of tongue had undergone either hemiglossectomy or subtotal glossectomy. Reconstruction was done with free radial forearm flap following oncosurgical resection and neck dissection. All of them received postoperative radiotherapy. Follow-up ranged from 2 months to 2 years. The age of the patients ranged between 32 and 65 years. Flap dimension ranged from 7x6 cm to 10x8 cm. Vascular anastomosis performed in an end-to-end manner with 8-0 Ethilon® under loupe magnifiacation. Results Venous congestion occurred in one patient after 48 hours postoperatively and the flap underwent complete necrosis on postoperative day 5. Postoperative hematoma was found in one patient within first 24 hours of reconstruction. Re-exploration was done immediately, blood clots were removed. No fresh bleeding point was seen and the flap survived. In this series, 12 out of 13 flaps survived completely (92%. Conclusion The free radial forearm flap has become a workhorse flap in head and reconstruction due to its lack of extra bulk, relative ease of dissection, long vascular pedicle, good calibre vessels, malleability and minimal donor site morbidity. Furthermore its low flap loss and complication rate offer the best choice for tongue reconstruction.

Narrowing beam-walking is a clinically feasible approach for assessing balance ability in lower-limb prosthesis users

OpenAIRE

Andrew Sawers; Brian J. Hafner

2018-01-01

Objective: Challenging clinical balance tests are needed to expose balance deficits in lower-limb prost-hesis users. This study examined whether narrowing beam-walking could overcome conceptual and practical limitations identified in fixed-width beam-walking. Design: Cross-sectional. Participants: Unilateral lower-limb prosthesis users. Methods: Participants walked 10 times along a low, narrowing beam. Performance was quantified using the normalize...

The Development of Skull Prosthesis Through Active Contour Model.

Science.gov (United States)

Chen, Yi-Wen; Shih, Cheng-Ting; Cheng, Chen-Yang; Lin, Yu-Cheng

2017-09-09

Skull defects result in brain infection and inadequate brain protection and pose a general danger to patient health. To avoid these situations and prevent re-injury, a prosthesis must be constructed and grafted onto the deficient region. With the development of rapid customization through additive manufacturing and 3D printing technology, skull prostheses can be fabricated accurately and efficiently prior to cranioplasty. However, an unfitted skull prosthesis made with a metal implant can cause repeated infection, potentially necessitating secondary surgery. This paper presents a method of creating suitably geometric graphics of skull defects to be applied in skull repair through active contour models. These models can be adjusted in each computed tomography slice according to the graphic features, and the curves representing the skull defect can be modeled. The generated graphics can adequately mimic the natural curvature of the complete skull. This method will enable clinical surgeons to rapidly implant customized prostheses, which is of particular importance in emergency surgery. The findings of this research can help surgeons provide patients with skull defects with treatment of the highest quality.

Bilateral electromyogram response latency following platform perturbation in unilateral transtibial prosthesis users: influence of weight distribution and limb position.

Science.gov (United States)

Rusaw, David; Hagberg, Kerstin; Nolan, Lee; Ramstrand, Nerrolyn

2013-01-01

Appropriate muscular response following an external perturbation is essential in preventing falls. Transtibial prosthesis users lack a foot-ankle complex and associated sensorimotor structures on the side with the prosthesis. The effect of this lack on rapid responses of the lower limb to external surface perturbations is unknown. The aim of the present study was to compare electromyogram (EMG) response latencies of otherwise healthy, unilateral, transtibial prosthesis users (n = 23, mean +/- standard deviation [SD] age = 48 +/- 14 yr) and a matched control group (n = 23, mean +/- SD age = 48 +/- 13 yr) following sudden support-surface rotations in the pitch plane (toes-up and toes-down). Perturbations were elicited in various weight-bearing and limb-perturbed conditions. The results indicated that transtibial prosthesis users have delayed responses of multiple muscles of the lower limb following perturbation, both in the intact and residual limbs. Weight-bearing had no influence on the response latency in the residual limb, but did on the intact limb. Which limb received the perturbation was found to influence the muscular response, with the intact limb showing a significantly delayed response when the perturbation was received only on the side with a prosthesis. These delayed responses may represent an increased risk of falling for individuals who use transtibial prostheses.

[CLINICAL APPLICATION OF OXFORD MOBILE-BEARING BIPOLAR PROSTHESIS UNICOMPARTMENTAL KNEE ARTHROPLASTY FOR SINGLE COMPARTMENTAL KNEE OSTEOARTHRITIS].

Science.gov (United States)

Wang, Shangzeng; Cheng, Shao; Wang, Yisheng

2016-01-01

To evaluate the effectiveness of Oxford mobile-bearing bipolar prosthesis unicompartmental knee arthroplasty (UKA) in the treatment of single compartmental knee osteoarthritis. Between June 2011 and July 2013, 22 cases of single compartmental knee osteoarthritis were treated by Oxford mobile-bearing bipolar prosthesis UKA. Of 22 cases, 8 were male and 14 were female with an average age of 65 years (range, 45-80 years); the left knee was involved in 12 cases, and the right knee in 10 cases, with a mean disease duration of 32.5 months (range, 8-90 months). The mean weight was 55.2 kg (range, 50-65 kg), and the mean body mass index was 20.8 kg/m2 (range, 17-25 kg/m2). Osteoarthritis involved in the single knee medial compartment in all patients. Knee society score (KSS) and range of motion (ROM) were measured to evaluate the knee joint function. Primary healing of incision was obtained in all patients, and there was no complication of infection, bedsore, or deep venous thrombosis. Postoperative follow-up was 2-4 years (mean, 3.2 years). The X-ray films showed good position of prosthesis, no prosthesis dislocation, or periprosthetic infection during follow-up. Knee ROM, KSS function score, and KSS clinical score were significantly improved at 1 week after operation and at last follow-up when compared with preoperative ones (P 0.05). Oxford mobile-bearing bipolar prosthesis UKA is an effective method to treat single compartmental knee osteoarthritis, with the advantages of less trauma, earlier rehabilitation exercise, near physiological state in joint function, and less risk of complications.

Patient-prosthesis mismatch and left ventricular remodelling after implantation of Shelhigh SuperStentless aortic valve prostheses.

Science.gov (United States)

Germing, A; Lindstaedt, M; Holt, S; Reber, D; Mügge, A; Laczkovics, A; Fritz, M

2008-08-01

Aortic valve replacement is a standard procedure for the treatment of severe aortic valve stenosis. Due to lower flow velocities stentless valves are associated with a more effective regression of left ventricular hypertrophy in comparison to stented valves. However, mismatch between body surface area and valve size supports unfavourable hemodynamic results. The aim of the study was to analyze hemodynamic parameters by echocardiography after implantation of the Shelhigh SuperStentless bioprosthesis and to analyze the occurrence of patient-prosthesis mismatch and left ventricular remodelling in this specific valve type. A total of 20 patients with severe aortic stenosis underwent implantation of a Shelhigh Super Stentless prosthesis. Clinical and echocardiographic assessment was done prior to, immediate after and six months after surgery. All surgical procedures were successful, no surgery-related complication was documented perioperatively. One patient died after development of multiorgan failure. Echocardiography during the first eight days after surgery showed mean gradients of 16 mmHg, mean valve orifice areas of 1.8 cm(2) and indexed effective orifice areas at 0.95 cm(2)/m(2). Six-months follow-up data were obtained in 19/20 patients. There were no relevant changes in echocardiographic hemodynamic findings at the time of follow-up measurements. Significant regression of left ventricular hypertrophy was shown (P=0.0088). A patient-prosthesis mismatch occurred in one patient (0.54 cm(2)/m(2)). No recurrent symptoms were documented. Patient-prosthesis mismatch after implantation of SuperStentless Shelhigh prosthesis is rare. A significant regression of left ventricular hypertrophy could be shown after six months. Hemodynamic valve function assessed by echocardiography may be predicted early after surgery.

Radial pseudoaneurysm following diagnostic coronary angiography

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Shankar Laudari

2015-06-01

Full Text Available The radial artery access has gained popularity as a method of diagnostic coronary catheterization compared to femoral artery puncture in terms of vascular complications and early ambulation. However, very rare complication like radial artery pseudoaneurysm may occur following cardiac catheterization which may give rise to serious consequences. Here, we report a patient with radial pseudoaneurysm following diagnostic coronary angiography. Adequate and correct methodology of compression of radial artery following puncture for maintaining hemostasis is the key to prevention.DOI: http://dx.doi.org/10.3126/jcmsn.v10i3.12776 Journal of College of Medical Sciences-Nepal, 2014, Vol-10, No-3, 48-50

Strain-stress analysis of surface prosthesis of hip joint

Czech Academy of Sciences Publication Activity Database

Návrat, Tomáš; Fuis, Vladimír; Florian, Z.; Hlavoň, Pavel

2007-01-01

Roč. 40, č. 2 (2007), S559-S559 ISSN 0021-9290. [ISB 2007. Taipei, 01.07.2007-05.07.2007] R&D Projects: GA ČR GA101/05/0136 Institutional research plan: CEZ:AV0Z20760514 Keywords : surface prosthesis * hip joint * FEM Subject RIV: BO - Biophysics Impact factor: 2.897, year: 2007

Penile prosthesis implant with bi-triangular excision and graft for surgical therapy of Peyronie’s disease: A case report

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Alexandre de Freitas Miranda

2016-01-01

Full Text Available We present a case of a 65-year-old man, who presented with moderate erectile dysfunction and a dorsal penile deviation of 60° caused by Peyronie’s disease. The patient underwent bi-triangularshaped plaque excision, followed by grafting and implantation of inflatable penile prosthesis. Complete penile straightening, without mechanical or geometric abnormalities, was achieved using bi-triangular excision and grafting. Postoperatively, the patient reported high satisfaction with the results and could perform sexual intercourse naturally. This novel technique corrects any degree of penile curvature, permits malleable and semi-rigid penile prosthesis implantation, avoids penile length loss, and eliminates additional incisions. To our knowledge, this case is the first in the literature in which the bi-triangular technique was successfully used for penile prosthesis implantation secondary to Peyronie’s disease. This new technique appears to be a good solution to correct penile curvature during penile prosthesis implantation for the treatment of Peyronie’s disease associated with erectile dysfunction.

Predictors of retention and attrition in a study of an advanced upper limb prosthesis: implications for adoption of the DEKA Arm.

Science.gov (United States)

Resnik, Linda; Cancio, Jill; Klinger, Shana; Latlief, Gail; Sasson, Nicole; Smurr-Walters, Lisa

2018-02-01

The purpose was to identify factors associated with completion of the VA home study of the DEKA Arm. Design and methodological procedures used: Differences between groups were examined using chi-square and t-tests. A multivariable logistic regression model predicting completion was generated and odds ratios (OR) for significant variables calculated. Post-hoc analysis was performed to plot the receiver operating characteristics (ROC) curve. Participants who completed were more likely to be prosthesis users at study onset (p = .03), and less likely to have a history of musculoskeletal problems (p = .047). There were no statistically significant differences between groups who completed and those who did not in gender, race, veteran status, age, body mass index (BMI), weight, height, musculoskeletal pain at baseline, satisfaction with current prosthesis, type of prosthesis, or months of prosthesis use. Two variables, prosthesis use and history of musculoskeletal problems were significant at p study a reasonable proxy for participant willingness to adopt the device; and believe that findings can be extrapolated to guide DEKA Arm prescription recommendations. Participants most likely to complete the study were already using a personal prosthesis, and without pre-existing musculoskeletal problems. Implications for rehabilitation Data from the VA Study of the DEKA Arm were analysed to determine which factors were associated with likely successful adoption of the DEKA Arm. Participants most likely to complete the study were those who already using a personal prosthesis, and those without pre-existing chronic or re-occurring musculoskeletal problems. This information may be useful when attempting to identify and target the most appropriate candidates for DEKA Arm prescription.

Endoscopic versus open radial artery harvest and mammario-radial versus aorto-radial grafting in patients undergoing coronary artery bypass surgery

DEFF Research Database (Denmark)

Carranza, Christian L; Ballegaard, Martin; Werner, Mads U

2014-01-01

the postoperative complications will be registered, and we will evaluate muscular function, scar appearance, vascular supply to the hand, and the graft patency including the patency of the central radial artery anastomosis. A patency evaluation by multi-slice computer tomography will be done at one year...... to aorto-radial revascularisation techniques but this objective is exploratory. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01848886.Danish Ethics committee number: H-3-2012-116.Danish Data Protection Agency: 2007-58-0015/jr.n:30-0838....

Silver-coated dacron prosthesis in the treatment of infection in arterial surgery: Case reports

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Nenezić Dragoslav

2008-01-01

Full Text Available INTRODUCTION Although the incidence is low, infection of prosthetic vascular graft bears a high incidence of serious complications including 25-75% mortality rate and 40-75% limb loss. The standard treatment of vascular graft infection consists of excision of the prosthesis, wound debridement and extraanatomic revascularization. Conservative treatment might be an option in a limited number of patients. We present three cases of surgical and conservative treatment of vascular graft infection. CASE OUTLINE Case 1: A patient developed silver-coated graft infection after femorodistal arterial reconstruction performed because of critical limb ischemia. In the early postoperative period, massive skin and subcutaneous tissue necrosis developed, with the graft being exposed. After two months of persistent debridement and wound toilette, the defect was covered with a Thiersch skin graft. Case 2: PTFE graft infection in the right groin followed reconstruction of the isolated common femoral artery aneurysm. This graft was replaced with a silver-coated graft in situ. Reinfection of the proximal end of the implanted silver-coated graft occurred and the graft was exposed. After repeated debridement and wound toilette, the exposed prosthesis was covered with granulomatous tissue, and the wound healed. Case 3: A year after anastomotic pseudoaneurysm resection in the left groin, prosthesis was exposed following wound infection. This graft was substituted with a silver-coated graft in situ. The wound healed primarily. CONCLUSION These three cases demonstrate that under some circumstances vascular prosthesis infection can be successfully treated conservatively without graft removal, and also by in situ replacement using silver-coated graft.

Numerical simulation of liquid-metal-flows in radial-toroidal-radial bends

International Nuclear Information System (INIS)

Molokov, S.; Buehler, L.

1993-09-01

Magnetohydrodynamic flows in a U-bend and right-angle bend are considered with reference to the radial-toroidal-radial concept of a self-cooled liquid-metal blanket. The ducts composing bends have rectangular cross-section. The applied magnetic field is aligned with the toroidal duct and perpendicular to the radial ones. At high Hartmann number the flow region is divided into cores and boundary layers of different types. The magnetohydrodynamic equations are reduced to a system of partial differential equations governing wall electric potentials and the core pressure. The system is solved numerically by two different methods. The first method is iterative with iteration between wall potential and the core pressure. The second method is a general one for the solution of the core flow equations in curvilinear coordinates generated by channel geometry and magnetic field orientation. Results obtained are in good agreement. They show, that the 3D-pressure drop of MHD flows in a U-bend is not a critical issue for blanket applications. (orig./HP) [de

Fabrication of a hollow bulb prosthesis for the rehabilitation of an acquired total maxillectomy defect

Science.gov (United States)

Vamsi Krishna, C H; Babu, Jaya Krishna; Fathima, Tanveer; Reddy, G V K

2014-01-01

The prosthodontic rehabilitation of maxillary defects is a challenging and demanding task which requires careful pre-surgical and post-surgical planning. Maxillary defects can be congenital or acquired. Acquired defects include those following trauma or surgical treatment of benign or malignant neoplasms. A prosthodontist encounters problems such as absence of support, poor retention, and lack of prosthesis stability in treating these patients. The present case report describes a procedure to fabricate a definitive hollow bulb obturator prosthesis for the rehabilitation of a total maxillectomy defect. PMID:24671313

EVALUATION AND RANKING OF ARTIFICIAL HIP PROSTHESIS SUPPLIERS BY USING A FUZZY TOPSIS METHODOLOGY

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Marija Zahar Djordjevic

2014-06-01

Full Text Available The aim of this study is to propose a fuzzy multi-criteria decision-making approach (MCDM to evaluate the artificial hip prosthesis suppliers with respect to numerous criteria, simultaneously, taking into account the type of each criteria and its relative importance. The fuzzy of the Technique for Order Preference by Similarity to Ideal Solution (FTOSISis applied in order to rank the artificial hip prosthesis suppliers. The rank is obtained using the process of fuzzy number comparison. Software solution based on suggested method is also presented. A real-life example with real data is presented to clarify the proposed method.

Tactile feedback is an effective instrument for the training of grasping with a prosthesis at low- and medium-force levels.

Science.gov (United States)

De Nunzio, Alessandro Marco; Dosen, Strahinja; Lemling, Sabrina; Markovic, Marko; Schweisfurth, Meike Annika; Ge, Nan; Graimann, Bernhard; Falla, Deborah; Farina, Dario

2017-08-01

Grasping is a complex task routinely performed in an anticipatory (feedforward) manner, where sensory feedback is responsible for learning and updating the internal model of grasp dynamics. This study aims at evaluating whether providing a proportional tactile force feedback during the myoelectric control of a prosthesis facilitates learning a stable internal model of the prosthesis force control. Ten able-bodied subjects controlled a sensorized myoelectric prosthesis performing four blocks of consecutive grasps at three levels of target force (30, 50, and 70%), repeatedly closing the fully opened hand. In the first and third block, the subjects received tactile and visual feedback, respectively, while during the second and fourth block, the feedback was removed. The subjects also performed an additional block with no feedback 1 day after the training (Retest). The median and interquartile range of the generated forces was computed to assess the accuracy and precision of force control. The results demonstrated that the feedback was indeed an effective instrument for the training of prosthesis control. After the training, the subjects were still able to accurately generate the desired force for the low and medium target (30 and 50% of maximum force available in a prosthesis), despite the feedback being removed within the session and during the retest (low target force). However, the training was substantially less successful for high forces (70% of prosthesis maximum force), where subjects exhibited a substantial loss of accuracy as soon as the feedback was removed. The precision of control decreased with higher forces and it was consistent across conditions, determined by an intrinsic variability of repeated myoelectric grasping. This study demonstrated that the subject could rely on the tactile feedback to adjust the motor command to the prosthesis across trials. The subjects adjusted the mean level of muscle activation (accuracy), whereas the precision could not

Dedicated radial ventriculography pigtail catheter

Energy Technology Data Exchange (ETDEWEB)

Vidovich, Mladen I., E-mail: miv@uic.edu

2013-05-15

A new dedicated cardiac ventriculography catheter was specifically designed for radial and upper arm arterial access approach. Two catheter configurations have been developed to facilitate retrograde crossing of the aortic valve and to conform to various subclavian, ascending aortic and left ventricular anatomies. The “short” dedicated radial ventriculography catheter is suited for horizontal ascending aortas, obese body habitus, short stature and small ventricular cavities. The “long” dedicated radial ventriculography catheter is suited for vertical ascending aortas, thin body habitus, tall stature and larger ventricular cavities. This new design allows for improved performance, faster and simpler insertion in the left ventricle which can reduce procedure time, radiation exposure and propensity for radial artery spasm due to excessive catheter manipulation. Two different catheter configurations allow for optimal catheter selection in a broad range of patient anatomies. The catheter is exceptionally stable during contrast power injection and provides equivalent cavity opacification to traditional femoral ventriculography catheter designs.

Designing and manufacturing an auricular prosthesis using computed tomography, 3-dimensional photographic imaging, and additive manufacturing: a clinical report.

Science.gov (United States)

Liacouras, Peter; Garnes, Jonathan; Roman, Norberto; Petrich, Anton; Grant, Gerald T

2011-02-01

The method of fabricating an auricular prosthesis by digitally positioning a mirror image of the soft tissue, then designing and using rapid prototyping to produce the mold, can reduce the steps and time needed to create a prosthesis by the traditional approach of sculpting either wax or clay. The purpose of this clinical report is to illustrate how the use of 3-dimensional (3-D) photography, computer technology, and additive manufacturing can extensively reduce many of the preliminary procedures currently used to create an auricular prosthesis. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

The influence of push-off timing in a robotic ankle-foot prosthesis on the energetics and mechanics of walking.

Science.gov (United States)

Malcolm, Philippe; Quesada, Roberto E; Caputo, Joshua M; Collins, Steven H

2015-02-22

Robotic ankle-foot prostheses that provide net positive push-off work can reduce the metabolic rate of walking for individuals with amputation, but benefits might be sensitive to push-off timing. Simple walking models suggest that preemptive push-off reduces center-of-mass work, possibly reducing metabolic rate. Studies with bilateral exoskeletons have found that push-off beginning before leading leg contact minimizes metabolic rate, but timing was not varied independently from push-off work, and the effects of push-off timing on biomechanics were not measured. Most lower-limb amputations are unilateral, which could also affect optimal timing. The goal of this study was to vary the timing of positive prosthesis push-off work in isolation and measure the effects on energetics, mechanics and muscle activity. We tested 10 able-bodied participants walking on a treadmill at 1.25 m · s(-1). Participants wore a tethered ankle-foot prosthesis emulator on one leg using a rigid boot adapter. We programmed the prosthesis to apply torque bursts that began between 46% and 56% of stride in different conditions. We iteratively adjusted torque magnitude to maintain constant net positive push-off work. When push-off began at or after leading leg contact, metabolic rate was about 10% lower than in a condition with Spring-like prosthesis behavior. When push-off began before leading leg contact, metabolic rate was not different from the Spring-like condition. Early push-off led to increased prosthesis-side vastus medialis and biceps femoris activity during push-off and increased variability in step length and prosthesis loading during push-off. Prosthesis push-off timing had no influence on intact-side leg center-of-mass collision work. Prosthesis push-off timing, isolated from push-off work, strongly affected metabolic rate, with optimal timing at or after intact-side heel contact. Increased thigh muscle activation and increased human variability appear to have caused the lack

Development of the two-part pattern during regeneration of the head in hydra

DEFF Research Database (Denmark)

Bode, Matthias; Awad, T A; Koizumi, O

1988-01-01

The head of a hydra is composed of two parts, a domed hypostome with a mouth at the top and a ring of tentacles below. When animals are decapitated a new head regenerates. During the process of regeneration the apical tip passes through a transient stage in which it exhibits tentacle......-like characteristics before becoming a hypostome. This was determined from markers which appeared before morphogenesis took place. The first was a monoclonal antibody, TS-19, that specifically binds to the ectodermal epithelial cells of the tentacles. The second was an antiserum against the peptide Arg......-Phe-amide (RFamide), which in the head of hydra is specific to the sensory cells of the hypostomal apex and the ganglion cells of the lower hypostome and tentacles. The TS-19 expression and the ganglion cells with RFamide-like immunoreactivity (RLI) arose first at the apex and spread radially. Once the tentacles...

Radial wave crystals: radially periodic structures from anisotropic metamaterials for engineering acoustic or electromagnetic waves.

Science.gov (United States)

Torrent, Daniel; Sánchez-Dehesa, José

2009-08-07

We demonstrate that metamaterials with anisotropic properties can be used to develop a new class of periodic structures that has been named radial wave crystals. They can be sonic or photonic, and wave propagation along the radial directions is obtained through Bloch states like in usual sonic or photonic crystals. The band structure of the proposed structures can be tailored in a large amount to get exciting novel wave phenomena. For example, it is shown that acoustical cavities based on radial sonic crystals can be employed as passive devices for beam forming or dynamically orientated antennas for sound localization.

A proposed intracortical visual prosthesis image processing system.

Science.gov (United States)

Srivastava, N R; Troyk, P

2005-01-01

It has been a goal of neuroprosthesis researchers to develop a system, which could provide artifical vision to a large population of individuals with blindness. It has been demonstrated by earlier researches that stimulating the visual cortex area electrically can evoke spatial visual percepts, i.e. phosphenes. The goal of visual cortex prosthesis is to stimulate the visual cortex area and generate a visual perception in real time to restore vision. Even though the normal working of the visual system is not been completely understood, the existing knowledge has inspired research groups to develop strategies to develop visual cortex prosthesis which can help blind patients in their daily activities. A major limitation in this work is the development of an image proceessing system for converting an electronic image, as captured by a camera, into a real-time data stream for stimulation of the implanted electrodes. This paper proposes a system, which will capture the image using a camera and use a dedicated hardware real time image processor to deliver electrical pulses to intracortical electrodes. This system has to be flexible enough to adapt to individual patients and to various strategies of image reconstruction. Here we consider a preliminary architecture for this system.

Psychosocial impact on anophthalmic patients wearing ocular prosthesis.

Science.gov (United States)

Goiato, M C; dos Santos, D M; Bannwart, L C; Moreno, A; Pesqueira, A A; Haddad, M F; dos Santos, E G

2013-01-01

The aim of this study was to assess the improvement in psychosocial awareness of anophthalmic patients wearing ocular prostheses and its relationship with demographic characteristics, factors of loss/treatment, social activity, and relationship between professional and patient. Surveys including a form for evaluation of psychosocial pattern were conducted with 40 anophthalmic patients rehabilitated with ocular prosthesis at the Center of Oral Oncology in the authors' dental school from January 1998 to November 2010. The improvement in psychosocial awareness was assessed by comparing the perception of some feelings reported in the period of eye loss and currently. Wilcoxon tests were applied for comparison of patients' perception between the periods. χ(2) tests were used to assess the relationship between the improvement in psychosocial awareness and the variables of the study. In addition, the logistic regression model measured this relationship with the measure of odds ratio. The feelings of shame, shyness, preoccupation with hiding it, sadness, insecurity and fear were significant for improvement in psychosocial awareness. It was concluded that the anophthalmic patients wearing an ocular prosthesis has significant improvement in psychosocial awareness after rehabilitation. Copyright © 2012 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Reconstruction of a midfacial defect using an intraoral-extraoral combination prosthesis employing magnets: a clinical report

OpenAIRE

Nair, Anoop; Regish, K M.; Shah, Farhan K.; Prithviraj, D R.

2012-01-01

Radical maxillectomy frequently leads to extended defects in hard and soft tissues that result in a connection between the oral cavities and orbit. If the defect cannot be surgically reconstructed, a combination prosthesis may be necessary to remedy dysfunction in patient function, comfort, esthetics. For minor defects, enlargement of the base of the intra oral prosthesis is generally sufficient. Resections that affect more than one third of the maxilla usually require an intra oral and an ex...

A pneumatic Bionic Voice prosthesis-Pre-clinical trials of controlling the voice onset and offset.

Science.gov (United States)

Ahmadi, Farzaneh; Noorian, Farzad; Novakovic, Daniel; van Schaik, André

2018-01-01

Despite emergent progress in many fields of bionics, a functional Bionic Voice prosthesis for laryngectomy patients (larynx amputees) has not yet been achieved, leading to a lifetime of vocal disability for these patients. This study introduces a novel framework of Pneumatic Bionic Voice Prostheses as an electronic adaptation of the Pneumatic Artificial Larynx (PAL) device. The PAL is a non-invasive mechanical voice source, driven exclusively by respiration with an exceptionally high voice quality, comparable to the existing gold standard of Tracheoesophageal (TE) voice prosthesis. Following PAL design closely as the reference, Pneumatic Bionic Voice Prostheses seem to have a strong potential to substitute the existing gold standard by generating a similar voice quality while remaining non-invasive and non-surgical. This paper designs the first Pneumatic Bionic Voice prosthesis and evaluates its onset and offset control against the PAL device through pre-clinical trials on one laryngectomy patient. The evaluation on a database of more than five hours of continuous/isolated speech recordings shows a close match between the onset/offset control of the Pneumatic Bionic Voice and the PAL with an accuracy of 98.45 ±0.54%. When implemented in real-time, the Pneumatic Bionic Voice prosthesis controller has an average onset/offset delay of 10 milliseconds compared to the PAL. Hence it addresses a major disadvantage of previous electronic voice prostheses, including myoelectric Bionic Voice, in meeting the short time-frames of controlling the onset/offset of the voice in continuous speech.

Mechanical properties of ramie fiber reinforced epoxy lamina composite for socket prosthesis

Directory of Open Access Journals (Sweden)

Tresna Soemardi

2010-10-01

Full Text Available This paper presents an investigation into the application of natural fiber composite especially ramie fiber reinforced epoxy lamina composite for socket prosthesis. The research focuses on the tensile and shear strength from ramie fiber reinforced epoxy lamina composite which will be applied as alternative material for socket prosthesis. The research based on American Society for Testing Material (ASTM standard D 3039/D 3039M for tensile strength and ASTM D 4255/D 4255M-83 for shear strength. The ramie fiber applied is a fiber continue 100 % Ne14'S with Epoxy Resin Bakelite EPR 174 as matrix and Epoxy Hardener V-140 as hardener. The sample composite test made by hand lay up method. Multiaxial characteristic from ramie fiber reinforced epoxy composite will be compared with ISO standard for plastic/polymer for health application and refers strength of material application at Prosthetics and Orthotics. The analysis was completed with the mode of the failure and the failure criterion observation by using Scanning Electron Microscope (SEM. Based on results of the research could be concluded that ramie fiber reinforced epoxy composite could be developed further as the alternative material for socket prosthesis on Vf 40-50%. Results of the research will be discussed in more detail in this paper.

Atraumatic patellar prosthesis dislocation with patellar tendon injury following a total knee arthroplasty: a case report

Directory of Open Access Journals (Sweden)

Singh Alka

2010-01-01

Full Text Available Abstract Introduction Total knee arthroplasty is a well-established procedure with gratifying results. There is no consensus in the literature whether to routinely resurface the patella while performing total knee arthroplasty or not. Although an extremely rare occurrence in clinical practice, patellar prosthesis dislocation is a possible complication resulting from total knee arthroplasty. Case presentation We report a rare case of atraumatic spontaneous dislocation of patellar prosthesis in a 63-year-old Caucasian man of British origin with patellar tendon injury. The patient was treated successfully through a revision of the patellar component and tendon repair. In two years follow-up the patient is asymptomatic with no sign of loosening of his patellar prosthesis. Conclusions A thorough understanding of knee biomechanics is imperative in performing total knee arthroplasty in order to achieve a better functional outcome and to prevent early prosthetic failure.

Aneurisma idiopático de artéria radial: relato de caso Idiopathic radial artery aneurysm: case report

Directory of Open Access Journals (Sweden)

Luiz Ernani Meira Jr.

2011-12-01

Full Text Available Os aneurismas da artéria radial são extremamente raros. Em sua maioria, consistem de pseudoaneurismas pós-traumáticos. Os aneurismas da artéria radial verdadeiros podem ser idiopáticos, congênitos, pós-estenóticos ou associados a patologias, tais como vasculites e doenças do tecido conjuntivo. Foi relatado um caso de aneurisma idiopático de artéria radial em uma criança de três anos, que, após completa investigação diagnóstica complementar, foi submetida à ressecção cirúrgica.Radial artery aneurysms are extremely rare. Post-traumatic pseudoaneurysms are the vast majority. True radial artery aneurysms can be idiopathic, congenital, poststenotic, or associated with some pathologies, such as vasculitis and conjunctive tissue diseases. We report a case of an idiopathic aneurysm of the radial artery in a three-year-old child who was submitted to surgical resection after a complete diagnostic approach.

Prosthetic Rehabilitation of a Patient with Mandibular Resection Prosthesis Using Mini Dental Implants (MDIs) – Case Report

OpenAIRE

Vojvodić, Denis; Čelebić, Asja; Mehulić, Ketij; Žabarović, Domagoj

2012-01-01

Physical disfigurement and functional impairments associated with facial trauma are a challenge to a prosthodontist, because even novel sophisticated surgical reconstructive techniques fail to provide adequate support for dental resection prosthesis. Therefore, different endosseous implants are often used as prosthesis-supporting elements. Manufacturers of dental implants have recently presented mini dental implants (MDIs) with diameter of only 1.8–2.4 mm. These implants allow very suitable p...

Classification of EMG signals using artificial neural networks for virtual hand prosthesis control.

Science.gov (United States)

Mattioli, Fernando E R; Lamounier, Edgard A; Cardoso, Alexandre; Soares, Alcimar B; Andrade, Adriano O

2011-01-01

Computer-based training systems have been widely studied in the field of human rehabilitation. In health applications, Virtual Reality presents itself as an appropriate tool to simulate training environments without exposing the patients to risks. In particular, virtual prosthetic devices have been used to reduce the great mental effort needed by patients fitted with myoelectric prosthesis, during the training stage. In this paper, the application of Virtual Reality in a hand prosthesis training system is presented. To achieve this, the possibility of exploring Neural Networks in a real-time classification system is discussed. The classification technique used in this work resulted in a 95% success rate when discriminating 4 different hand movements.

78 FR 9010 - Dental Devices; Reclassification of Temporary Mandibular Condyle Prosthesis

Science.gov (United States)

2013-02-07

.... FDA-2012-N-1239] Dental Devices; Reclassification of Temporary Mandibular Condyle Prosthesis AGENCY... condyle prostheses into class III, based on the recommendation of a Dental Products Panel (the Panel... Administration, Dental Products Advisory Panel Meeting Transcript, February 12, 1997; http://www.accessdata.fda...

Radial lean direct injection burner

Science.gov (United States)

Khan, Abdul Rafey; Kraemer, Gilbert Otto; Stevenson, Christian Xavier

2012-09-04

A burner for use in a gas turbine engine includes a burner tube having an inlet end and an outlet end; a plurality of air passages extending axially in the burner tube configured to convey air flows from the inlet end to the outlet end; a plurality of fuel passages extending axially along the burner tube and spaced around the plurality of air passage configured to convey fuel from the inlet end to the outlet end; and a radial air swirler provided at the outlet end configured to direct the air flows radially toward the outlet end and impart swirl to the air flows. The radial air swirler includes a plurality of vanes to direct and swirl the air flows and an end plate. The end plate includes a plurality of fuel injection holes to inject the fuel radially into the swirling air flows. A method of mixing air and fuel in a burner of a gas turbine is also provided. The burner includes a burner tube including an inlet end, an outlet end, a plurality of axial air passages, and a plurality of axial fuel passages. The method includes introducing an air flow into the air passages at the inlet end; introducing a fuel into fuel passages; swirling the air flow at the outlet end; and radially injecting the fuel into the swirling air flow.

VARIABLE STIFFNESS HAND PROSTHESIS: A SYSTEMATIC REVIEW

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S. Cecilia Tapia-Siles

2017-06-01

Full Text Available Prosthetics is an important field in engineering due to the large number of amputees worldwide and the associated problems such as limited functionality of the state of the art. An important functionality of the human hand is its capability of adjusting the stiffness of the joints depending on the currently performed task. For the development of new technology it is important to understand the limitations of existing resources. As part of our efforts to develop a variable stiffness grasper for developing countries a systematic review was performed covering technology of body powered and myoelectric hand prosthesis. Focus of the review is readiness of prosthetic hands regarding their capability of controlling the stiffness of the end effector. Publications sourced through three different digital libraries were systematically reviewed on the basis of the PRISMA standard. We present a search strategy as well as the PRISMA assessment of the resulting records which covered 321 publications. The records were assessed and the results are presented for the ability of devices to control their joint stiffness. The review indicates that body powered prosthesis are preferred to myoelectric hands due to the reduced cost, the simplicity of use and because of their inherent ability to provide feedback to the user. Stiffness control was identified but has not been fully covered in the current state of the art. In addition we summarise the identified requirements on prosthetic hands as well as related information which can support the development of new prosthetics.