Tele-rehabilitation of patients with gait abnormalities could benefit from continuous monitoring of knee joint angle in the home and community. Continuous monitoring with mobile devices can be restricted by the number of body-worn sensors, signal bandwidth, and the complexity of operating algorithms. Therefore, this paper proposes a novel algorithm for estimating knee joint angle using lower limb angular velocity, obtained with only two leg-mounted gyroscopes. This gyroscope only (GO) algorithm calculates knee angle by integrating gyroscope-derived knee angular velocity signal, and thus avoids reliance on noisy accelerometer data. To eliminate drift in gyroscope data, a zero-angle update derived from a characteristic point in the knee angular velocity is applied to every stride. The concurrent validity and construct convergent validity of the GO algorithm was determined with two existing IMU-based algorithms, complementary and Kalman filters, and an optical motion capture system, respectively. Bland–Altman analysis indicated a high-level of agreement between the GO algorithm and other measures of knee angle.

Background: Achieving mobility with a prosthesis is a common post‐amputation rehabilitation goal and primary outcome in prosthetic research studies. Patient‐reported outcome measures (PROMs) available to measure prosthetic mobility have practical and psychometric limitations that inhibit their use in clinical care and research.Objective: To develop a brief, clinically meaningful, and psychometrically robust PROM to measure prosthetic mobility.Design: A cross‐sectional study was conducted to administer previously developed candidate items to a national sample of lower limb prosthesis users. Items were calibrated to an item response theory model and two fixed‐length short forms were created. Instruments were assessed for readability, effective range of measurement, agreement with the full item bank, ceiling and floor effects, convergent validity, and known groups validity.Setting: Participants were recruited using flyers posted in hospitals and prosthetics clinics across the United States, magazine advertisements, notices posted to consumer websites, and direct mailings.Participants: Adult prosthesis users (N = 1091) with unilateral lower limb amputation due to traumatic or dysvascular causes.Interventions: Not applicable.Main Outcome Measures: Candidate items (N = 105) were administered along with the Patient Reported Outcome Measurement Information System Brief Profile, Prosthesis Evaluation Questionnaire – Mobility Subscale, and Activities‐Specific Balance Confidence Scale, and questions created to characterize respondents.Results: A bank of 44 calibrated self‐report items, termed the Prosthetic Limb Users Survey of Mobility (PLUS‐M), was produced. Clinical and statistical criteria were used to select items for 7‐ and 12‐item short forms. PLUS‐M instruments had an 8th grade reading level, measured with precision across a wide range of respondents, exhibited little‐to‐no ceiling or floor effects, correlated expectedly with scores from existing PROMs, and differentiated between groups of respondents expected to have different levels of mobility.Conclusion: The PLUS‐M appears to be well suited to measuring prosthetic mobility in people with lower limb amputation. PLUS‐M instruments are recommended for use in clinical and research settings.

Background: Postural asymmetries are thought to lead to impairment of body structure and function such as muscle imbalance, gait asymmetry and possible chronic conditions, which result in limitation of mobility and restriction of daily activity for transfemoral amputees (TFAs). Despite the potential clinical impact, postural asymmetries have not been confirmed or quantified in TFAs. Objectives: To identify the presence of postural asymmetries in TFAs utilizing clinical evaluation measures. Study design: An observational cross-sectional study in which participants were evaluated at a single time point without intervention or follow-up. Methods: Forty-seven unilateral TFAs were measured for standing limb length, pelvic innominate inclination (PII), lateral trunk flexion and hip extension. Results: Limb length discrepancy was present in 66% of participants and 57% had a short prosthetic limb. PII was greater than has been reported in the literature, and the shorter the prosthetic lower limb, the greater the PII on the amputated side (r = −0.422, p = 0.004). Limb length discrepancy and decreased lateral trunk flexion accounted for 26% of the variance in amputated side PII. Conclusion: Three postural measurements, namely leg length, pelvic innominate inclination and hip extension, were found to differ between the intact and amputated limb in this study sample. Clinical relevance Clinicians should include postural assessment as part of their routine evaluation of TFAs in an effort to achieve postural symmetry and reduce the risk of chronic conditions associated with impairment of body structure and function.

The purpose of this study was to examine the possible relationship between factors modifiable by rehabilitation interventions (rehabilitation factors), other factors related to lower-limb loss (other factors), and high-level mobility as measured by the Comprehensive High-Level Activity Mobility Predictor (CHAMP) in servicemembers (SMs) with traumatic lower-limb loss. One-hundred eighteen male SMs with either unilateral transtibial amputation (TTA), unilateral transfemoral amputation (TFA), or bilateral lower-limb amputation (BLLA) participated. Stepwise regression analysis was used to develop separate regression models of factors predicting CHAMP score. Regression models containing both rehabilitation factors and other factors explained 81% (TTA), 36% (TFA), and 91% (BLLA) of the variance in CHAMP score. Rehabilitation factors such as lower-limb strength and dynamic balance were found to be significantly related to CHAMP score and can be enhanced with the appropriate intervention. Further, the findings support the importance of salvaging the knee joint and its effect on high-level mobility capabilities. Lastly, the J-shaped energy storage and return feet were found to improve high-level mobility for SMs with TTA. These results could help guide rehabilitation and aid in developing appropriate interventions to assist in maximizing high-level mobility capabilities for SMs with traumatic lower-limb loss.

Background: The literature comparing bone-anchored prosthesis (BAP) with socket prosthesis (SP) consistently reports improvement in physical health and quality of life using primarily patient-reported outcome measures (PROMs). Objective: To determine the differences in mobility and balance using performance-based outcome measures and PROMs in people with transfemoral amputations (TFAs) fitted with BAP vs. SP. Study design: Causal comparative. Methods: Two groups of people with TFAs were recruited: one using a BAP (N = 11; mean age ± standard deviation, 44 ± 14.9 years; mean residual limb length as a percentage of the intact femur, 68% ± 15.9) and another group using a SP (N = 11; mean age ± standard deviation, 49.6 ± 16.0 years; mean residual limb length as a percentage of the intact femur, 81% ± 13.9), and completed the 10-meter walk test, component timed-up-and-go, Prosthetic Limb Users Survey of Mobility™ 12-item, and Activities-specific Balance Confidence Scale. Results: There were no statistically significant differences between the BAP and SP groups in temporal spatial gait parameters and prosthetic mobility as measured by the 10-meter walk test and component timed-up-and-go, yet large effect sizes were found for several variables. In addition, Activities-specific Balance Confidence Scale and Prosthetic Limb Users Survey of Mobility™ scores were not statistically different between the BAP and SP groups, yet a large effect sizes were found for both variables. Conclusions: This study found that people with TFA who use a BAP can demonstrate similar temporal spatial gait parameters and prosthetic mobility, as well as self-perceived balance confidence and prosthetic mobility as SP users. Therefore, suggesting that the osseointegration reconstruction surgical procedure provides an alternative option for a specific population with TFA who cannot wear nor have limitations with a SP. Future research with a larger sample and other performance-based outcome measures and PROMs of prosthetic mobility and balance would further determine the differences between the prosthetic options.