Walking Biomechanics Associated With Patellofemoral Pain In Sedentary And Active Emerging Adult Women

Abstract

About 50% of emerging adults do not meet the national physical activity recommendations. Risk of injury, like patellofemoral pain (PFP) during walking, may be a barrier to meeting the physical activity recommendations for sedentary emerging adults. PURPOSE: To determine if sedentary emerging adult women had walking biomechanics related to PFP compared to active emerging adult women. METHODS: As part of a larger study, 26 (12 sedentary, 14 active) emerging adult women (age:22(3) years; height: 1.58(0.08) m; mass: 58.4(8.7) kg) participated in the study. Anatomical and tracking retro-reflective markers were placed on body segments to record movement. Participants completed 5 good walking trials at 1.4 m/s (± 5%). Three-dimensional gait analysis was performed using motion capture sampling at 200 Hz and force platforms sampling at 1000Hz. Joint angles were determined using the joint coordinate system and moment was determined using inverse dynamics. The variables of interest were peak knee flexion angle, peak internal knee extensor moment (PKEM), knee abduction and external rotation angles at PKEM, and hip adduction and internal rotation angles at PKEM. Independent t-tests compared variables between sedentary and active emerging adult women. Effect sizes (d) were calculated for each variable. RESULTS: Knee external rotation angle at PKEM was significantly larger in sedentary compared to active emerging adult women (Table 1). There were no other significant differences between the sedentary and active groups for the remaining variables of interest. CONCLUSION: A larger knee external rotation angle at PKEM suggests higher pressure on the lateral patella in the sedentary versus active group. According to the pathomechanical model for PFP, high lateral pressure and associated high cartilage stress is a mechanism for the develop of PFP. Therefore, sedentary women may be more at risk for developing PFP during walking for exercise compared to active women.Table 1:: hip and knee biomechanics during walking in sedentary and active emerging adult women