Changes in lower extremity joint moments one-year following osseointegration in individuals with Transfemoral lower-limb amputation: A case series.

BACKGROUND: Dissatisfaction with socket prostheses has led to the development of bone-anchored prostheses through osseointegration for people with transfemoral amputation, eliminating the need for a prosthetic socket. Gait deviations of transfemoral prosthesis users may be linked to increased risk of osteoarthritis, and it remains unknown if gait biomechanics change following osseointegration. The purpose of this case series was to evaluate the longitudinal changes in joint kinetics one year post-osseointegration in patients with transfemoral amputation during walking. METHODS: Knee, hip, and trunk internal moments were evaluated in the prosthetic and intact limbs during walking at a self-selected speed in four participants pre- and one-year post-osseointegration. Longitudinal changes were quantified using the percent change (%∆) in peak joint moments between the two time points and Cohen's d (d) effect size was used to determine the magnitude of effect on joint moments during walking one year following osseointegration. FINDINGS: Participants demonstrated increased peak knee extension moment (224 ± 308%∆, d = -1.31) in the prosthetic limb, while demonstrating reduced peak knee extension moment (-43 ± 34%∆, d = 1.82) in the intact limb post-osseointegration. Participants demonstrated bilateral reduction of peak hip extension moment (prosthetic: -22 ± 37%∆, d = 0.86; intact: -29 ± 10%∆, d = 1.27) and bilateral increase of peak hip abduction moment (prosthetic: 45 ± 40%∆, d = 1.20; intact: 23 ± 44%∆, d = 0.74) post-osseointegration. Participants demonstrated reduced peak trunk moments on both the prosthetic (extension: -31 ± 16%∆, d = 1.51; lateral flexion: -21 ± 20%∆, d = 0.63) and intact side (extension: -7 ± 22%∆, d = 0.38; lateral flexion: -22 ± 18%∆, d = 1.12) post-osseointegration. INTERPRETATION: This case series suggests improved gait symmetry in individuals with transfemoral amputation one year following osseointegration, justifying future investigation.

Improvements in disability and function in people with lower-limb amputation one year after prosthesis osseointegration.

BACKGROUND: People with lower-limb amputation (LLA) are routinely prescribed a socket prosthesis; however, many socket prosthesis users experience severe complications with the fit of their prosthesis including residual limb wounds and pain. Osseointegration is a procedure that creates a direct connection between the bone and prosthetic limb through a bone-anchored prosthesis, eliminating the need for a socket interface. It is offered as a secondary procedure to people with LLA who experience significant complications with socket prostheses. OBJECTIVES: To evaluate change in disability and function 1 year postosseointegration compared with preosseointegration in people with LLA. STUDY DESIGN: Single group, pretest, and post-test. METHODS: Twelve participants (9 transfemoral and 3 transtibial amputations, age: 44 ± 10 years, 7 female participants, 14 ± 12 years since amputation) with unilateral LLA underwent osseointegration with press-fit implants. Disability was measured with the World Health Organization Disability Assessment Schedule 2.0, and function was measured with both Prosthetic Limb Users Mobility Survey and the Activities-Specific Balance Confidence Scale. Questionnaires were administered preosseointegration and 1 year postosseointegration. Paired t tests assessed change in outcomes between time points. RESULTS: Postosseointegration, participants demonstrated reduced disability measured with World Health Organization Disability Assessment Schedule 2.0 (%Δ = -52.6, p = 0.01), improved mobility measured with Prosthetic Limb Users Mobility Survey (%Δ = 21.8, P < 0.01), and improved balance confidence measured with the Activities-Specific Balance Confidence Scale (%Δ = 28.4, P < 0.01). CONCLUSIONS: Participants report less disability and greater function in their prosthesis postosseointegration. Osseointegration is a novel procedure for people experiencing complications with their socket prosthesis, and this study is the first to show improvements in disability postosseointegration.