Matthew J. Mastenbrook, BS
Study Design
Secondary analysis, cross-sectional study.
Background
Chronic hip joint pain (CHJP) can lead to limitations in activity participation, but the musculoskeletal factors associated with the condition are relatively unknown. Understanding the factors associated with CHJP may help develop rehabilitation strategies to improve quality of life of individuals with long-term hip pain.
Objectives
To compare measures of hip abductor muscle volume and hip abductor muscle strength between women with CHJP and asymptomatic controls.
Methods
Thirty women, 15 with CHJP and 15 matched asymptomatic controls (18-40 years of age), participated in this study. Magnetic resonance imaging was used to determine the volume of the primary hip abductor muscles, consisting of gluteus medius (GMed), gluteus minimus (GMin), a small portion of gluteus maximus (GMax), and tensor fascia latae (TFL), within a defined region of interest. Break tests were performed using a handheld dynamometer to assess hip abductor strength. During the strength test, the participant was positioned in sidelying with the involved hip in 15° abduction. Independent-sample t tests were used to compare muscle volume and strength values between those with CHJP and asymptomatic controls.
Results
Compared to asymptomatic controls, women with CHJP demonstrated significantly increased gluteal muscle volume (228±40cm3 versus 199±29cm3; p=.032), but decreased hip abductor strength (74.6±16.8Nm versus 93.6±20.2Nm; p=.009). There were no significant differences in TFL muscle volume between the two groups (p=.640).
Conclusions
Women with CHJP appear to have larger gluteal muscles, but decreased hip abductor strength compared to asymptomatic controls. J Orthop Sports Phys Ther, Epub 9 Oct 2017. doi:10.2519/jospt.2017.7380