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.