Generalized Joint Laxity Is Associated With Dynamic Hip Ultrasonography Measures in Female Athlete Patients Who Are Not Hypermobile.

Abstract

To investigate ultrasound (US) femoroacetabular translation measurements in female athlete patients. A prospective cross-sectional study was conducted in female athlete patients <50 years. Demographic data, Beighton score/hypermobility status, and sport participation were collected. Hip dysplasia was determined using radiographic measurements (lateral center edge angle, anterior center edge angle, Tönnis angle); femoral version angles were measured with CT or MR. Femoroacetabular translation US measures included neutral (N), neutral flexed (NF), extension external rotation/apprehension (EER) positions. Maximal difference (delta) between US measures was calculated. 206/349 female hips were analyzed (median age 21.2 years [range, 12-49.5]). The primary sport group was performing arts (45%, 92/206). Mean Beighton score was 5.2 (SD, 2.5) with 61% (129/206) of hips exhibiting hypermobility (Beighton score ≥5). For each additional unit of Beighton score, N US measurement increased by 0.7 mm (β=0.7; 95% confidence interval [CI]=0.22-1.25; P < .001), NF by 1 mm ( = 0.9; 95% CI=0.3-1.43; P=.002) and EER by 0.8 mm ( = 0.8; 95% CI=0.27-1.37; P < .001) when adjusting for age and dysplasia status. A positive correlation was detected between NF (r=0.19; 95% CI=0.05-0.33; P=.007) and EER (r=0.19; 95% CI=0.05-0.32; P=.01) with Tönnis angle and a negative correlation between the delta and femoral version (r=-0.20; 95% CI=-0.35 to 0.03; P=.02). No difference in US measures was detected across sport groups (N [P=.24], NF [P=.51], EER [P=.20], delta [P=.07]). Beighton score was independently associated with dynamic US measures in female athlete patients who are not hypermobile when controlling for other factors.