Clinical and radiographic predictors of intra-articular hip disease in arthroscopy

Background: The arthroscopic treatment of intra-articular hip disease and associated structural abnormalities continues to evolve. Nevertheless, contemporary diagnostic tools have significant limitations in predicting severity of disease preoperatively. Hypothesis: Clinical characteristics and radiographic parameters correlate with and predict intra-articular disease patterns in patients undergoing hip arthroscopy. Study Design: Cohort study; Level of evidence, 3. Methods: In sum, 355 hips in 338 patients undergoing hip arthroscopy by a single surgeon were retrospectively reviewed. Clinical characteristics and radiographic findings (on anteroposterior pelvis and frog lateral radiographs) of mild dysplasia, cam, and pincer-type femoroacetabular impingement were compared with intraoperative labral and chondral disease patterns. Results: Labral tears were present in 90.1% of hips, and acetabular cartilage lesions were present in 67.3%, including 41.7% with grade 3 or 4 chondromalacia. Multivariate logistic regression analysis found male sex, older age (<30, 30-50, >50 years old), Tönnis osteoarthritis grade, and alpha angle >50° on frog lateral radiograph to be independently associated with increased risk of grade 3 or 4 acetabular chondromalacia (all P <.001). Insidious onset of pain (in contrast to acute onset) was independently associated with the presence of acetabular chondromalacia (P =.002). Cam-type femoroacetabular impingement (alpha angle >50°) was strongly associated with more severe labral disease (P <.001). Findings of acetabular dysplasia and pincer femoroacetabular impingement did not remain significantly associated with acetabular chondral disease in the multivariate analysis. Conclusion: Several clinical and radiographic characteristics-most notably, male sex, older age, Tönnis grade, and elevated alpha angle-are associated with more severe intra-articular hip disease. The recognition of these associations between clinical and radiographic characteristics and hip disease patterns is important for patient selection, surgical planning, and patient counseling.