By Jordana Bieze Foster
A pain-inducing protocol significantly reduces hip extension strength in patients with patellofemoral pain (PFP), suggesting that hip weakness associated with the condition may be a result and not a cause, according to research from the University of Wisconsin-Milwaukee presented in June at the NATA meeting.
Nineteen runners with PFP of at least four weeks duration completed a pain-inducing protocol involving single-leg squats on the affected limb and repeated for 10 sets of 20 repetitions or until a previously determined pain threshold was reached. Participants completed a median of three sets.
Compared to baseline, the increased pain was associated with significant decreases in hip extensor strength, hip extensor moment, and hip abduction moment during running.
“These findings seem to indicate that pain causes weakness and is not just a symptom,” said David Bazett-Jones, PhD, a lecturer in the Physical Therapy Program at the university, who presented the findings at the NATA meeting.
Rehabilitation to restore hip weakness in patients with PFP is still important, Bazett-Jones noted.
Bazett-Jones DM, Cobb SC, O’Connor K, et al. Functionally increased pain decreases strength and influences mechanics in patients with patellofemoral pain. Presented at the 63rd annual meeting of the National Athletic Trainers Association, St. Louis, MO, June 2012.