Effects of a hip brace on biomechanics and pain in people with femoroacetabular impingement.

OBJECTIVES

This study evaluates whether hip bracing in patients with femoroacetabular impingement (FAI) (a) immediately reduces range of hip internal rotation, flexion, adduction, and pain during functional tasks; and (b) improves patient-reported outcomes when worn daily over 4 weeks.

DESIGN

Within-participant design followed by a case series.

METHODS

Twenty-five adults with symptomatic FAI underwent 3D kinematic assessment with and without a hip brace during single-leg squat, double-leg squat, stair ascent, and stair descent. A subset of this population (n=17) continued to wear the brace daily for 4-weeks. A linear mixed statistical model was used to assess pain and kinematic differences between the braced and unbraced conditions at baseline testing. Patient-reported outcomes (NRS pain, iHot-33 and HAGOS questionnaires) at 4-weeks were compared to baseline using paired t-tests.

RESULTS

Bracing resulted in significant but small reductions in peak hip flexion ranging between 5.3° (95% CI 0.8°-9.7°) and 5.6° (95% CI 1.1°-10.0°), internal rotation ranging between 2.5° (95% CI 0.6°-4.4°) and 6.4° (95% CI 4.5°-8.2°), and adduction ranging between 2.2° (95% CI 0.5°-3.8°) and 3.3° (95% CI 1.6°-5.0°) during all tasks, except flexion during single-leg squat, compared with the unbraced condition; pain was not significantly improved with the brace. Bracing over four weeks did not significantly change patient-reported outcomes.

CONCLUSIONS

Bracing subtly limited impinging hip movements during functional tasks, but did not immediately reduce pain or improve patient-reported clinical outcomes after 4 weeks in a young adult cohort with long-standing FAI.