Context : Individuals with chronic hip-related groin pain display impaired dynamic postural control as measured by the modified star excursion balance test; however, the kinematics and kinetics displayed have not been reported in chronic hip-related groin pain populations. Hip joint kinematics during various tasks differ between males and females with chronic hip-related groin pain; however, few studies have reported trunk kinematics or hip joint loading. We were curious if sex differences exist in trunk, hip, and pelvis kinematics and hip joint loading during the modified star excursion balance test among those with chronic hip-related groin pain. Design : Cross-sectional. Methods : Patients with chronic hip-related groin pain performed 3 trials of the modified star excursion balance test, reaching in anterior, posteromedial, and posterolateral directions. We used a motion capture system and force plates to capture hip, pelvis, and trunk kinematic and kinetic data. Variables of interest included reach distance, normalized by leg length, and sagittal and frontal plane hip, pelvis, and trunk kinematics and hip joint kinetics at the time of max reach. We used independent t tests or Wilcoxon rank sum tests to assess between-group differences. Results : Compared with males (n = 11, age = 28 years, body mass index = 25.0 kg/m 2 ), females (n = 17, age = 25 years, body mass index = 22.1 kg/m 2 ) displayed larger hip adduction angle during anterior (12.6° vs 6.1°, P = .048) and posteromedial (1.5° vs −4.6°, P = .043) directions, larger contralateral pelvic drop angle during anterior direction (−1.7° vs 2.3°, P = .014), smaller trunk flexion angle during posteromedial direction (25.8° vs 34.8°, P = .045), and smaller hip flexion moment during posterolateral direction (0.56 vs 0.87 N·m/kg, P = .021). Females and males displayed similar reach distances. Conclusion : Movement strategies differ between sexes, with females displaying more hip adduction motion, more contralateral pelvic drop, less trunk flexion motion, and smaller hip flexion moments.
Swick et al. (Thu,) studied this question.