Gait Patterns Differ In Patients With Knee Osteoarthritis With And Without Transfemoral Amputation

PURPOSE: To compare gait kinematics between individuals with knee osteoarthritis (KOA) with and without unilateral transfemoral amputation (TF) and measure the relationship between strength and gait mechanics. METHODS: Five individuals with unilateral TF (3F/2M, 61.0 ± 5.8 years, 90.4 ± 20.3 kg, 168.7 ± 11.7 cm) and symptomatic KOA in the intact limb were matched with 9 individuals with KOA (CON) without leg amputation (4F/5M, 66.1 ± 9.9 years, 87.6 ± 21.0 kg, 173.0 ± 10.2 cm) for strength measures and gait analysis on a split-belt treadmill at a self-selected speed. Gait kinematics were analyzed using waveform analysis with 90% confidence intervals. Differences between groups were considered significant if the 90% confidence intervals did not overlap for three or more consecutive points and were reported as mean differences (MD) ± standard deviation. Associations between kinematic measures during the first and second 50% of stance and quadriceps and hamstring isokinetic peak torque (PT) were evaluated using Pearson’s correlation coefficient (r) for the involved limb (with symptomatic KOA). RESULTS: The TF group demonstrated greater knee flexion (6.1 ± 1.5°), knee external rotation (6.6 ± .86°), hip external rotation (3.5 ± .25°), and trunk rotation (6.4 ± 1.4°) compared to the CON group during stance. The TF group also demonstrated reduced knee varus (2.5 ± .31°) and hip adduction (4.0 ± .69°) compared to the CON group. The TF group exhibited significant negative correlation between quadriceps PT and peak hip abduction (r = -.89;p = .043) while the CON group had significant negative correlation between quadriceps PT and peak trunk flexion (r = -.76;p = .017) during the first 50% of stance. During the second half of stance, the TF group exhibited significant negative correlation between hamstring PT and peak hip abduction (r = -.88;p = .049), while the CON group exhibited significant negative correlations between quadriceps PT and peak trunk flexion (r = -.79;p = .011) and peak trunk lateral flexion (r = -.67;p = .05). CONCLUSIONS: Patients with unilateral TF and KOA in their intact limb demonstrate significantly different gait patterns than CON with KOA during stance. Further, isokinetic strength is associated with peak hip abduction in the TF group while it is associated with trunk kinematics in the CON group during stance. UIC Applied Health Sciences Interdisciplinary Pilot Award