Context: Symptomatic Femoroacetabular Impingement Syndrome (FAIS) is a painful condition that leads to decreased function. It is currently unknown how walking gait changes over time following surgery for FAIS earlier than one year, or how these changes present in females.
Objective: The purpose was to determine biomechanical gait differences between females with FAIS/labral tears and controls pre-operatively, and three- and six-months post-operatively.
Design: Case-Control Study.
Setting: Gait laboratory.
Participants: The study included 18 female participants (n=9 FAIS patients, n=9 controls).
Main Outcome Measures: Between-group comparisons of the Hip Outcome Score activity of daily living subscale (HOSadl) and gait biomechanics were evaluated at pre-operative and three- and six-months post-operative sessions. Statistical parametric mapping was conducted on normalized time-series data.
Results: Pre-operatively, the FAIS group had poor HOSadl scores [Pre-operative: 64.1 (15.4), Controls 100.0 (0), p<0.001;], walked 15% slower, and had several gait differences compared to controls. Three months post-operatively, the FAIS group had greater vGRF (p=0.013), ankle dorsiflexion angles (p=0.021), and external dorsiflexion moment (p=0.012) in midstance, as well as greater knee flexion through the second half of stance (p<0.001). The FAIS group also demonstrated less hip extension (p=0.024) and hip abduction (p=0.010) through the second half of stance, which transitioned into less hip extension (p=0.040) and hip abduction (p=0.025) during the subsequent swing phase. The FAIS improved their HOSadl to 87.6 (7.6) by 6-months post-operatively and had greater dorsiflexion moment (p=0.003) and ankle external rotation during stance (p=0.033). The FAIS patients also showed greater external hip ER moment in late stance (p<0.001).
Conclusions: The most biomechanical differences between groups occurred 3-months post-operatively, suggesting that female FAIS patients have more post-operative gait compensations in the short term after surgery. By six-month post-operatively, the patient reported outcomes greatly improved and there were few gait differences compared to the control group.