Ligamentum Teres Tears and Femoroacetabular Impingement: Prevalence and Preoperative Findings.

ABSTRACT

PURPOSE: To determine prevalence of ligamentum teres (LT) injuries identified during hip arthroscopy for treatment of femoroacetabular impingement (FAI) and to identify physical examination findings or radiographic characteristics specific to patients with complete LT tears that could possibly assist in a preoperative diagnosis. METHODS: Between October 2006 and June 2015, prospective data were collected on consecutive hip arthroscopies. Inclusion criterion was primary hip arthroscopy in patients aged 18 years or older. All patients in the study were treated for chondrolabral dysfunction associated with FAI. Patients with prior hip surgery were excluded. A total of 2,213 out of 3,158 hip arthroscopies met the inclusion criterion. RESULTS: Of the 2,213 hips, 233 (11%) had a normal LT, 1,947 (88%) had frayed/partially torn, and 33 (1.5%) had a torn LT. A higher prevalence of torn LT was seen in female subjects. Patients with torn LT had lower body mass index (BMI) (22.5 v 24.7; P < .01) than those with hips with normal LT. On radiographs, patients with torn LTs had a lower center edge angle and had increased odds of having a center edge angle less than 25°. Isolated cam or isolated pincer were seen more often in hips with torn LT than in hips with normal LT. Hips with torn LT were 3.1 times more likely to have a chondral defect on the femoral head than were hips with normal LT (95% confidence interval [CI], 1.2-8.7) and were 3.6 times more likely to have capsular laxity diagnosed at hip arthroscopy than were hips with normal LT (95% CI, 1.4-9.4). CONCLUSIONS: Among patients with FAI and labral pathology, complete tears of the LT were rare and were more likely to be seen in women and those with lower BMI and low center edge angles at arthroscopy. LT tears were associated with hip laxity and chondral defects of the femoral head. LEVEL OF EVIDENCE Level IV, prognostic case series.