FUNCTIONAL DIFFERENCES OF BILATERAL TRANSFEMORAL AMPUTEES USING FULL-LENGTH AND STUBBY-LENGTH PROSTHESES

Mechanical loading of bone-anchored implants during functional performance tests in service members with transfemoral limb loss

Introduction

For individuals with limb loss, bone-anchored implants create a direct structural and functional connection to a terminal prosthesis. Here, we characterized the mechanical loads distal to the abutment during several functional performance tests in Service members with transfemoral (TF) limb loss, to expand on prior work evaluating more steady-state ambulation on level ground or slopes/stairs.

Methods

Two males with unilateral TF limb loss and two males with bilateral TF limb loss participated after two-stage osseointegration (24 and 12 months, respectively). Tri-directional forces and moments were wirelessly recorded through a sensor, fit distal to the abutment, during six functional tests: Timed Up and Go (TUG), Four Square Step Test (FSST), Six Minute Walk Test (6MWT), Edgren Side-Step Test (SST), T-Test (TTEST), and Illinois Agility Test (IAT). Additionally, participants performed a straight-line gait evaluation on a 15 m level walkway at a self-selected speed (0.93-1.24 m/s). Peak values for each component of force and moment were extracted from all six functional tests; percent differences compared each peak with respect to the corresponding mean peak in straight-line walking.

Results

Peak mechanical loads were largest during non-steady state components of the functional tests (e.g., side-stepping during SST or TTEST, standing up from the ground during IAT). Relative to walking, peak forces during functional tests were larger by up to 143% (anterior-posterior), 181% (medial-lateral), and 110% (axial); peak moments were larger by up to 108% (flexion-extension), 50% (ab/adduction), and 211% (internal/external rotation).

Conclusions

A more comprehensive understanding of the mechanical loads applied to bone-anchored implants during a variety of activities is critical to maximize implant survivability and long-term outcomes, particularly for Service members who are generally young at time of injury and return to active lifestyles.

Prosthetic Rehabilitation of a Female With Bilateral Transfemoral Amputation in Japan: A Case Report

Individuals with bilateral transfemoral (TF) amputation experience difficulties when walking with lower limb prostheses. Walking with prostheses is even more difficult when the cause of the amputation is nontraumatic, or the gender is female. We provided prosthetic rehabilitation to a woman who underwent bilateral TF amputation due to internal disease.  A 42-year-old woman underwent bilateral TF amputation for ischemic necrosis of the lower extremities during septic shock treatment. Upon admission to our convalescent rehabilitation ward 3 months after surgery, the patient weighed 32 kg and was underweight. After admission, she underwent strength training of the trunk and hip muscles, hip joint range of motion exercises, and bottom shuffle exercises on the physical therapy table. The prosthetist created stubby prostheses for standing and standing-up exercises on the floor, as well as gait exercises. We gradually extended the length of her prostheses and subsequently switched her knee joints to Ottobock locking and polycentric knees and eventually to Kenevo, which are microprocessor-controlled prosthetic knees (MPK). During occupational sessions, she practiced household activities such as washing dishes, cleaning, and cooking while wearing her prostheses. Six months after admission, the patient was discharged and could walk outdoors alone with two canes without using a wheelchair. At discharge, the Kenevo modes were Mode C on the right and Mode B + on the left. The patient's weight recovered to 41 kg. The patient completed the 10-meter walk test at 0.50 m/s at a comfortable walking speed, the 6-minute walk test at 180 meters, and the timed up and go (TUG) test in 26 seconds. The motor Functional Independence Measure (FIM) score was improved from 60 on admission to 83 on discharge.  Strengthening the hip and trunk muscles, improving endurance and balance, preventing hip contracture, and maintaining the hip range of motion are necessary for walking with bilateral TF prostheses. In the prosthetic rehabilitation of bilateral TF amputations, stubby prostheses, protocols for gradual extension of the prosthetic length, and Kenevo, a mode-changeable MPK, are helpful. MPK is essential for individuals with bilateral TF amputations to walk independently and use their prostheses daily. This report is a valuable reference for healthcare professionals involved with bilateral TF amputees in the future who need prosthetic rehabilitation.

'It's more than just a running leg': a qualitative study of running-specific prosthesis use by children and youth with lower limb absence

PURPOSE

The purpose of this study was to investigate the use of running-specific prostheses (RSPs) by children with lower limb absence (LLA) along with the benefits and challenges of RSPs.

MATERIALS AND METHODS

In this descriptive qualitative study, eight children (ages 8-20 years) and their parents participated in semi-structured interviews. The interviews were audio-recorded and transcribed. Coded data were the foundation for central theme development.

RESULTS

Three main themes were generated. "Run faster, jump higher, do more" (the benefits of RSP use), "Every leg serves its purpose" (comparing functionality between daily use prostheses and RSPs), and "A lot more to think about" (additional considerations with RSP use).

CONCLUSIONS

RSPs have a positive impact in promoting children's engagement in sports and physical activities. While some children used their RSP primarily for running, others wore it for a broader range of physical activities. Issues with balance and discomfort caused by leg length discrepancies and/or ill-fitting sockets limited daily wear time. Limitations related to current RSP designs and clinical implementation should be addressed to optimize the functional potential of children with unilateral or bilateral LLA.Implications for rehabilitationRunning-specific prostheses (RSPs) positively impacted children's ability to participate in some sports with peers promoting their physical and social well-being.The main issues that children faced were discomfort, difficulty balancing, and inability to use RSPs for certain sports, while parents' issues focused on supporting prosthesis use and transport, and adjustments of different prostheses to keep up with their child's growth.Clinicians should be aware of the challenges of RSP use to best support children and their families.Designers should focus on addressing limitations with current RSPs to facilitate the diverse needs of pediatric users.

Assessment of the relationship between rectus femoris cross-sectional area and knee extension strength in the prosthesis users with transtibial amputation: A case-control study

Objectives

This study aims to investigate cross-sectional area of the amputated-limb rectus femoris compared to the intact-limb and controls and to determine its correlation with functional strength and walking tests in prosthesis users with transtibial amputation.

Patients and methods

Between October 2018 and April 2019, a total of 14 prosthesis users (12 males, 2 females; mean age: 47.1±16.2 years; range, 26 to 73 years) who met the inclusion criteria, and 14 age-, sex-, and dominancy-matched able-bodied controls (12 males, 2 females; mean age: 47.1±16.2 years; range, 26 to 73 years) were included in this case-control study. Cross-sectional area of rectus femoris (CSA-RF) was evaluated bilaterally by two independent examiners. Knee extension strength was measured bilaterally by using a handheld dynamometer. Functional strength and walking were assessed by Step-Up-Over and Walk-Across tests of the NeuroCom Balance Master® device.

Results

The CSA-RF was found to be reduced in amputated-limb compared to the intact-limb and able-bodied controls (p<0.01). In the prosthesis users, the cross-sectional area difference between both limbs rectus femoris muscles was shown to be correlated with actual and functional knee extension strength, step length, and walking speed (p<0.05). Intra- and inter-observer reliability of CSA-RF on both sides were found to be good to excellent (intraclass correlation coefficient: 0.856-0.936).

Conclusion

Ultrasonographic measurement of CSA-RF is a valid and reliable tool to assess the functional strength and walking in the prosthesis users with unilateral transtibial amputation.

Analysis of patient outcome and owner satisfaction with double limb amputations: 14 dogs and four cats

OBJECTIVE

To evaluate the indications for, complications of, and surgical outcomes of dogs and cats that were treated with double limb amputations.

ANIMALS

14 dogs and 4 cats that underwent double limb amputations.

PROCEDURES

Data collected retrospectively included patient-specific (species, age, weight, breed, sex, existing comorbidities) and amputation-specific (indication for amputation, full or partial limb amputation, associated complications, need for revision surgeries) variables. Owner satisfaction scores were also collected.

RESULTS

The most common indication for double amputations was trauma (12/18) patients. Eleven patients had both amputations performed simultaneously. Nine patients had double partial limb amputations versus full limb amputations. Twelve patients underwent bilateral pelvic limb amputations, 4 underwent bilateral thoracic limb amputations, and 2 had 1 pelvic and 1 contralateral thoracic limb amputated. Five patients had reported complications over the course of the follow-up period, and complications for 3 patients were considered major. Revision surgery was reported for 2 animals. Owner satisfaction scores were reported as very satisfied/excellent (14/18), mildly satisfied (3/18), and strongly dissatisfied (1/18). Median time to follow-up was 450 days (range, 85 to 4,380 days).

CLINICAL RELEVANCE

Double limb amputation may be a viable alternative to advanced limb-sparing procedures or humane euthanasia based on the owner satisfaction data and the relatively low rate of major complications in this study. Future studies should clarify patient selection criteria and differences in function between surgical types.

Selecting, Administering, and Interpreting Outcome Measures among Adults with Lower-Limb Loss: An Update for Clinicians

Purpose of review

To summarize outcome measurement research among adults with lower-limb loss (LLL) for clinicians.

Recent findings

Houghton Scale, Prosthetic Evaluation Questionnaire-mobility subscale (PEQ-m), Prosthetic Limb Users Survey of Mobility (PLUS-M™), Activities-Specific Balance Confidence Scale (ABC), Amputee Mobility Predictor (AMP), Comprehensive High-Level Activity Mobility Predictor, Four Square Step Test (FSST), Narrowing Beam Walking Test (NBWT), L Test, 10 Meter Walk Test (10MWT), and 6 Minute Walk Test (6MWT) are appropriate for evaluating individual patient changes post-LLL. Post-LLL, Socket Comfort Score, Patient-Specific Functional Scale, Patient-Reported Outcomes Measurement Information System 29-Item Profile, Timed Up and Go, and 2 Minute Walk Test may be more appropriate for evaluating groups. Minimal detectable change is available for 15/20 reviewed measures. Many measures differ between mobility levels.

Summary

Quick, reliable measures for evaluating patient functional change include ABC, PEQ-m, PLUS-M™, FSST, and L Test; when resources allow, NBWT, 10MWT, 6WMT and AMP may be considered.