Canadian Prosthetics Orthotics Journal最新文献

Background: Transtibial prosthesis socket trim lines have remained fairly consistent over the past decade, and based on methods such as a supracondylar cuff suspension. However, with vacuum suspension methods, trim lines can change.

Objective: An objective of this technical note was to inform practitioners how to fabricate a socket in a better way. A step-by-step fabrication guide is provided for the prosthetist.

Methods: A unilateral transtibial amputee was selected for this technical note. We provide a detailed description of the different steps of fabrication as well as patient feedback. The fabrication involved fabrication of a vacuum socket using Pre-preg carbon fiber and anti-bacterial Ethylene-Vinyl-Acetate (EVA), as a proximal flexible brim.

Findings: The properties of EVA and Pre-preg carbon fiber allow for fabrication of a transtibial socket with a flexible proximal brim. The new design resulted in greater comfort and increased range of motion in the patient studied. The patient subjectively noted enhanced squatting and cycling capabilities while using the updated socket and flexible proximal brim.

Conclusion: This technical note presented a fabrication guide for a new style of socket and preliminary patient feedback. Clinical studies evaluating functional and biomechanical effects of this new socket design are needed.

Background: Small residual limb-socket displacement is a good indicator of prosthetic suspension system quality. Active vacuum suspension systems can decrease vertical movement inside the socket, compared to non-active suction systems. This study mechanically evaluated limb-socket displacement with the Össur Unity active vacuum system.

Method: Forty-eight conditions were evaluated: four cylindrical and four conical sockets (polypropylene, polyethylene terephthalate glycol-modified (PETG), thermoset resin (acrylic), Thermolyn soft materials); two Iceross Seal-In V liners (standard, high profile); three vacuum conditions (active vacuum, inactive vacuum, no suction with valve open). An Instron 4428 test machine applied 0-100N linear ramped tensile loads to each positive mold, with the socket secured in place, while displacement between the mold and socket was recorded. Following the displacement tests, the load before failure (i.e., 10 mm displacement) was measured.

Results: Average and standard deviations for movement between the mold and sockets were small. The displacement average for all conditions was 0.30±0.16mm for active vacuum, 0.32±0.16mm for inactive vacuum, and 0.39±0.22mm for no suction. Across all trials, active vacuum systems tolerated significantly (p<0.001) more load before failure (812±221N) compared to inactive vacuum (727±213N), and no suction (401±184N). The maximum load before failure (1142±53N) was for the cylindrical polypropylene socket and high-profile liner.

Conclusion: The Unity system successfully controlled pistoning inside the socket for regular activity loads and also controlled the greatest traction loads. While relative movement was smallest for Unity, all conditions (inactive vacuum, no suction) were viable for loads less than 100N. Furthermore, similar results can be achieved when using different socket fabrication materials.

Case description: Good residual limb skin health is vital to successful prosthetic prescription. Unnatural loading profiles and excessive sweating can lead to skin and soft tissue problems. Perforated liners allow the transport of moisture away from the skin and allow negative pressure (a condition that has been shown to aid wound healing) to act directly on the residuum surface.

Aim: Assess the effects of perforated prosthetic liner use, particularly with respect to wound healing.

Method: Three patient histories were retrospectively reviewed following prescription of perforated prosthetic liners due to excessive sweating or prolonged residual limb health concerns. Photographic records from patient files were used to document changes in residual limb condition. Patients also provided subjective feedback regarding their experiences.

Findings: Two cases described active amputees with persistent blistering irritated during exercise. Another case described a patient of low mobility level with a history of residual limb skin infections. All saw their conditions heal and reported a reduction in problematic sweating. Two patients reported cancelling surgical interventions after substantial improvements with the perforated liner.

Discussion: These findings provide evidence that the use of perforated prosthetic liners allow improvements in residual limb health, while still permitting prosthetic use.

Background: The majority of lower limb amputations (LLA) in Canada are dysvascular due to complications of diabetes and/or vascular disease. Traditionally dysvascular amputations have occurred in the elderly. With younger onset of adult diabetes, amputations are now occurring in non-geriatric populations. An understanding of younger patients with dysvascular LLA is needed to determine their risk factors, and unique health and psychosocial challenges.

Objectives: To obtain a depiction of the key demographic and impairment characteristics of adults 65 years and younger with dysvascular LLA undergoing inpatient rehabilitation.

Methodology: A retrospective chart review was completed on inpatient adult amputation rehabilitation patients over a five year period. Data extracted included socio-demographics, Functional Independence Measure (FIM) scores, comorbidities, and discharge outcomes.

Findings: One hundred and forty-three patients who were 65 years and younger were included, which represented almost a quarter of all admissions. Most patients were male (79%) with an average age of 55 years old (SD=8). The majority (72%) were unemployed. The mean number of co-morbidities was 5.2 (SD=8.2). Individuals discharged home (n=122) had higher (p<0.05) FIM scores than those readmitted to acute care or discharged to long-term care (n=20).

Conclusions: Similar to the literature on older dysvascular LLA patients, our study found high rates of disability and co-morbidities in younger patients with dysvascular LLA, which might impact their ability to work. Given these challenges, better amputation prevention strategies and targeted rehabilitation programming for this population are needed.

Background: Residual limb neuromas are a significant cause of post-amputation pain. There is little knowledge concerning ultrasound-guided (US) radiofrequency ablation (RFA) as treatment.

Objective: To investigate US-guided RFA for neuroma associated pain in individuals with limb amputation.

Methodology: The notes of nine consecutive patients were retrospectively reviewed. Information obtained included neuroma size and nerve, RFA duration/temperature, pain scores, analgesic requirements and ease/comfort of prosthetic use. Eight patients had lower-limb amputations and one had a trans-radial amputation. All except one, underwent diagnostic US-guided steroid injection to confirm the neuroma as the source of pain, prior to RFA.

Results: Six patients reported significant reduction in pain scores (defined as at least 50% reduction) and an improvement in comfort/ease of wearing their prosthetic limb, with no adverse effects. Three of these six patients also reported a reduction in analgesic requirements. Of the three remaining patients - one had a large sciatic nerve neuroma that was eventually surgically excised, another had confounding pain from an adjacent bony spur, whilst the third patient did not receive a routine diagnostic steroid injection prior to RFA.

Conclusions: Our findings suggest that US-guided RFA is safe and effective for small to medium-sized residual limb neuroma associated pain in individuals with limb amputation. It can reduce pain and analgesic requirements, improve comfort/ease of wearing the prosthesis and potentially avoid surgical excision. We recommend patients should undergo a diagnostic steroid injection prior to RFA to confirm that the neuroma is the source of pain.

Study design: Retrospective analysis.

Background: The gait characteristics of transtibial amputees (TTs) have been described many times. In general, the literature reported nearly consistent results for the kinematic and kinetic parameters of the prosthetic side. However, the literature revealed inconsistent findings on kinetic parameters for determining the risk of developing knee osteoarthritis, such as the peak knee adduction moment, knee flexion moment and vertical ground reaction forces.

Objectives: The objective of our study was to describe the sagittal kinetic and kinematic gait characteristics of the ankle and residual knee joint of the prosthetic limb and the knee loading parameters of the sound side of unilateral TTs. This specific consideration may contribute to resolving the controversy of these parameters in the literature.

Methods: We analysed our database containing gait analyses from 53 unilateral TTs and compared data to a control group (CG), also taken from our database. The sagittal kinetic and kinematic gait characteristics of the ankle and residual knee joint of the prosthetic limb, and selected knee loading parameters of the sound side (the peak knee adduction moment, knee flexion moment and vertical ground reaction forces) were evaluated. Beside these parameters we reported typical spatiotemporal gait parameters as gait velocity, step length, step length asymmetry, stance phase duration and asymmetry of stance phase duration.

Results: The TTs walked slower and more asymmetrically than the CG. The kinematic pattern of the prosthetic ankle differed from that found in the CG. The largest difference was observed for the range of motion of the plantarflexion at push-off, which was significantly reduced for the prosthetic foot. The residual knee joint was generally affected with respect to decreased moments and reduced knee flexion during stance phase. The peaks of the vertical ground reaction forces and knee adduction moments showed no differences between the sound side of amputees and the CG. The peak knee flexion moment at midstance was significantly reduced for the sound side of amputees in comparison with the CG.

Conclusion: The biomechanical data measured for the prosthetic side in a cohort of 53 unilateral TT amputees conformed with the literature. The parameters determining the risk of developing knee osteoarthritis investigated in our retrospective analysis were not increased on the sound side in comparison with non-amputees. We deem it reasonable to assume that an appropriate prosthesis will reduce the likelihood of overloading the knee on the sound side during normal walking.