Proximal and distal kinematics in female runners with patellofemoral pain

Abstract

Background: Female runners have a high incidence of developing patellofemoral pain. Abnormal mechanics are thought to be an important contributing factor to patellofemoral pain. However, the contribution of abnormal trunk, hip, and foot mechanics to the development of patellofemoral pain within this cohort remains elusive. Therefore the aim of this study was to determine if significant differences during running exist in hip, trunk and foot kinematics between females with and without patellofemoral pain.

Methods: 32 female runners (16 patellofemoral pain, 16 healthy control) participated in this study. All individuals underwent an instrumented gait analysis. Between-group comparisons were made for hip adduction, hip internal rotation, contra-lateral pelvic drop, contra-lateral trunk lean, rearfoot eversion, tibial internal rotation, as well as forefoot dorsiflexion and abduction

Findings: The patellofemoral pain group had significantly greater peak hip adduction and hip internal rotation. No differences in contra-lateral pelvic drop were found. A trend towards reduced contra-lateral trunk lean was found in the patellofemoral pain group. No significant differences were found in any of the rearfoot or forefoot variables but significantly greater shank internal rotation was found in the patellofemoral pain group.

Interpretation: We found greater hip adduction, hip internal rotation and shank internal rotation in female runners with patellofemoral pain. We also found less contra-lateral trunk lean in the patellofemoral pain group. This may be a potential compensatory mechanism for the poor hip control seen. Rehabilitation programs that correct abnormal hip and shank kinematics are warranted in this population.

Fig. 1

A) Hip adduction ensemble averages for the PFP group and the healthy control group. Hip adduction is positive. B) Hip internal rotation ensemble averages for the PFP group and the healthy control group. Hip internal rotation is positive. C) Contra-lateral pelvic drop ensemble averages for the PFP group and the healthy control group. Contra-lateral pelvic drop is negative. D) Contra-lateral trunk lean ensemble averages for the PFP group and the healthy control group. Contra-lateral lean is negative.

Fig. 2

A comparison between hip internal rotation between PFP subjects who overly compensated vs. those who did not. Both subgroups of PFP subjects landed in greater hip internal rotation than the control group. Hip internal rotation is positive.

Fig. 3

A) Rear foot eversion ensemble curves for the PFP group and healthy control group. Rear foot eversion is negative. B) Forefoot dorsiflexion curves for the PFP group and healthy control group. Forefoot dorsiflexion is positive. C) Forefoot abduction curves for the PFP and healthy control group. Forefoot abduction is negative. D) Shank internal rotation for the PFP and healthy control group. Shank internal rotation is negative.