Background

Femoroacetabular impingement (FAI) is a frequent source of hip pain that may predispose one to early chondrolabral damage. Our study aimed to investigate the correlation between radiographic measurements and intraoperative hip pathology as well as the arthroscopic procedures performed between hips of patients who underwent staged bilateral hip arthroscopy.

Methods

A retrospective analysis was performed on a prospectively maintained multicenter registry of patients undergoing primary hip arthroscopy for FAI. All patients with complete demographic data and preoperative imaging were included. Patients were separated by their first and second surgery. Intra-patient correlations were determined for demographic data, radiographic findings, intraoperative pathology, and arthroscopic procedures performed. Univariate analysis was performed using ?² and Fisher’s Exact test and paired t-tests for ordinal and continuous variables, respectively. Pearson’s product-moment and point-biserial tests were used to determine correlations.

Results

Sixty patients were included in the study. There were significant differences between patient’s age at surgery (years; 29.7 ± 14.3 vs. 30 ± 14.2; P < 0.001) and Tönnis angle ( 4.8 ± 3.4° vs. 5.7 ± 3.4°; P = 0.044). Demographic data, including age, sex, body mass index (BMI), and laterality, demonstrated strong correlations (Pearson’s coefficients 0.999, 1.000, 0.944, -1.000, respectively; P < 0.001). Radiographic data, including Tönnis grade, Alpha Angle, Lateral Center Edge Angle, Tönnis Angle, Posterior Wall Sign, and Cross-Over Sign, demonstrated strong correlations (Pearson’s coefficients 1.000, 0.776, 0.543, 0.704, 0.765, 0.537, respectively; P < 0.001). Diagnosis of labral tear complexity, length, and degeneration, hyperplastic labrum, cam/pincer-impingement, articular cartilage damage (BECK grade > 2), and presence of loose bodies were all moderately to strongly correlated (Pearson’s correlations 0.705, 0.336, 0.541, 0.730, 0.425, 0.606, 0.805, 0.965, respectively; P < 0.001). Intraoperative findings of acetabular chondrosis were moderately correlated (Pearson’s correlation 0.323; P = 0.012). Arthroscopic procedures performed, including acetabuloplasty, femoroplasty, acetabular and femoral chondroplasty, synovectomy, Ligamentum Teres debridement, loose body removal, subspine decompression, capsulotomy type, and capsular treatment, were all moderately to strongly correlated (Pearson’s correlations 0.627, 0.602, 0.356, 0.482, 0.335, 0.449, 0.695, 0.907, 0.898, respectively; P < 0.01).

Conclusion

This study demonstrated a high degree of correlation between radiographic findings and intraoperative pathology as well as for the procedures performed between hips for patients. These findings may help inform presurgical planning for patients undergoing staged bilateral hip arthroscopies.