Gait speed as an indicator of prosthetic walking potential following lower limb amputation

Background: The relationship between gait speed and prosthetic potential (K-level classifications) and function has not been explored among people transitioning from hospital rehabilitation to the community. Objectives: To examine gait speed at discharge from inpatient rehabilitation among people prescribed a prosthetic leg after unilateral lower limb amputation, and associations between gait speed, prosthetic potential and functional ability. Study design: Cohort. Methods: Gait speed (10-m walk test), K-level (Amputee Mobility Predictor) and Functional Independence Measure motor were compared for 110 people (mean (standard deviation) age: 63 (13) years, 77% male, 71% transtibial amputation, 70% dysvascular causes). Results: Median (interquartile range) gait speed and Functional Independence Measure motor were 0.52 (0.37-0.67) m/s and 84 (81, 85), respectively. Median (IQR) gait speed scores for each K-level were as follows: K1 = 0.17 (0.15-0.19) m/s, K2 = 0.38 (0.25-0.54) m/s, K3 = 0.63 (0.50-0.71) m/s and K4 = 1.06 (0.95-1.18) m/s. Median (IQR) FIM-Motor scores for each K-level were as follows: K1 = 82 (69-84), K2 = 83 (79-84), K3 = 85 (83-87) and K4 = 87 (86-89). Faster gait speed was associated with higher K-level, higher FIM-Motor, being younger, male and having transtibial amputation with nonvascular aetiology. Conclusion: Gait speed was faster among each higher K-level classification. However, gait speeds observed across all K-levels were slower than healthy populations, consistent with values indicating high risk of morbidity and mortality.