By Jordana Bieze Foster
Patients with patellofemoral pain (PFP) have less medial longitudinal arch excursion during stair descent than healthy individuals, according to a Brazilian study that may help explain the effects of foot orthoses in patients with PFP.
Researchers from the University of Sao Paulo analyzed foot posture and motion in 15 healthy women and 15 women with PFP as they descended five stairs at a controlled cadence of 96 steps per minute. All participants in the PFP group had been symptomatic for at least two months.
Static medial longitudinal arch angle (MLAA) was significantly greater, indicating a lower arch, in the PFP group than the control group. Dynamic MLAA did not differ significantly between groups, but arch excursion was significantly smaller in the PFP group.
Pain levels increased significantly in the PFP group after the stair descent task, which is typically challenging for patients with PFP; the researchers theorized that the limited arch excursion was a compensatory response to the pain. The findings were presented in September at the annual ASB meeting.
Aliberti S, Mezencino B, Amadio AC, et al. Static and dynamic medial longitudinal arch angle in patellofemoral pain syndrome individuals. Presented at the American Society of Biomechanics 2013 Annual Meeting, Omaha, NE, September 2013.