Associations between weight-bearing asymmetry and demographic factors during quiet standing in individuals with unilateral transfemoral amputation.

Background: Individuals with unilateral transfemoral amputation (uTFA) are at increased risk of secondary musculoskeletal conditions due to excessive loading on the intact limb during functional activities. However, limited evidence exists regarding weight-bearing asymmetry during quiet standing in this population.

Research question: Is weight-bearing asymmetry during quiet standing associated with demographic characteristics in physically active individuals with uTFA?

Methods: Thirty-four individuals with uTFA were recruited. Participants stood naturally with each foot on a separate force platform while vertical ground reaction forces were recorded over 5 s. The weight-bearing ratio (WBR) was calculated as the ratio of load on the intact limb to that on the prosthetic limb. Correlation analyses assessed associations between WBR and age, height, body mass, and time since amputation (TSAmp). Group comparisons were conducted based on sex, residual limb length, prosthetic knee type (microprocessor vs. non-microprocessor), and athletic proficiency (Paralympian vs. non-Paralympian).

Results: No significant correlations were found between WBR and demographic variables, sex, residual limb length or prosthetic knee type. However, Paralympians exhibited significantly more symmetrical weight-bearing than non-Paralympians.

Significance: These findings indicate that athletic proficiency may be associated with more symmetrical weight-bearing during quiet standing in individuals with uTFA. However, the underlying mechanisms remain unclear, and further research is needed to confirm these observations and explore the role of sports participation in postural balance and asymmetry-related outcomes.