Peak Muscle Activity During Stance Phase in Women with Patellofemoral Pain versus Without Patellofemoral Pain

Background: Weak hip external rotation has been speculated to be connected to PFP. However, muscle activity of hip musculature has yet to be investigated during gait with individuals who report PFP. Objective: The purpose of this study was to compare peak muscle activity in the hip during stance phase of a ۱۰ meter walk between females with and without patellofemoral pain (PFP). Methods: Eight females with PFP and eleven females without PFP volunteered for this study. Peak muscle activity of the adductor longus (AL), tensor fascia latae (TFL), gluteus medius (GMED), and gluteus maximas (GMAX) were measured using surface electromyography (EMG). Participants completed ۳ trials of a ۱۰m walk while surface EMG was recorded. Muscle co-activation, total time spent in stance, and total walk time were also compared between groups. Four separate independent sample t-test were conducted to compare participants without PFP (n = ۱۱) and participants with PFP (n = ۹) for peak muscle activation, muscle co-activation, total stance time, and total walk time. Results: Peak muscle activity in the AL, TFL, GMED, and GMAX were not significantly different in female participants with and without PFP. Although, peak TFL muscle activity in participants with PFP (M = ۰.۱۶۶۴, SD = ۰.۱۱۳۶۰) was higher compared to participants without PFP (M = ۰.۱۰۱۶, SD = ۰.۵۹۳۷). There were no statistically significant differences in muscle co-activation or ۱۰m walk time between participants with and without PFP. However, time spent in stance time approached statistical significance, p = ۰.۰۵۹. Conclusion: There are no differences in peak muscle activity in the AL, TFL, GMED, and GMAX between females with and without patellofemoral pain (PFP) during stance phase of a ۱۰m walk.

Keywords:

Patellofemoral Joint , Electromyography (EMG) , Walking