Walking biomechanics in women with patellofemoral osteoarthritis differ compared to men with and women without patellofemoral osteoarthritis

Background: Differences in walking biomechanics between women and men with patellofemoral joint (PF) osteoarthritis (OA) may contribute to the development or progression of persistent symptoms in people with PF OA.

Objective: Evaluate how walking biomechanics of women with PF OA differ from: (i) men with PFJ OA; and (ii) women without PF OA. Second, explore the relationship between knee-related symptoms/function and walking biomechanics in individuals with PF OA, and whether these are modified by sex.

Methods: Sixty-seven individuals with PF OA (43 women) and 14 women without PF OA were included. Biomechanics data were recorded during walking. Patient-reported symptoms and function were obtained using the Knee injury and Osteoarthritis Outcome Score. Differences in continuous biomechanical data were assessed using statistical parametric mapping, with discrete data and relationships evaluated using linear models.

Results: Women with PF OA walked with a greater hip adduction angle throughout stance (t > 2.757) and lower impulses for the hip flexion, knee flexion, and ankle dorsiflexion moments (adjusted mean differences [95% CI]:3.3 × 10^-2 [-4.9 × 10^-2, -1.6 × 10^-2], -2.9 × 10^-2 [-5.3 × 10^-2, -0.4 × 10^-2], -5.1 × 10^-2 [-8.2 × 10^-2, -2.0 × 10^-2] Nms/kg, respectively) compared to men with PF OA. Compared to their asymptomatic peers, women with PF OA displayed a 5° offset towards greater hip flexion. Higher knee adduction moment impulse correlated with worse KOOS-ADL scores in men, not women.

Conclusion: Observed biomechanical differences were small in nature with moderate to weak relationship observed with the KOOS. Findings were not limited to the knee, indicating that women with PF OA display unique biomechanical features across the kinetic-chain.