Clinical Outcomes of Hip Arthroscopy in Radiographically Diagnosed Retroverted Acetabula
Background: Symptomatic global retroversion of the acetabulum, as diagnosed on plain radiographs of the pelvis, has traditionally been treated with reverse periacetabular osteotomy, which improves posterior undercoverage and eliminates the anterior pincer lesion. There is a paucity of literature on hip arthroscopy in this group, secondary to theoretical concern of iatrogenic dysplasia, subsequent instability, and arthritis.
Purpose: To evaluate the outcomes of hip arthroscopy for patients with a radiographic diagnosis of acetabular retroversion, using patient-reported outcomes, visual analog scale (VAS), patient satisfaction, and pre- and postoperative Tönnis grades.
Study design: Case series; Level of evidence, 4.
Methods: Pre- and postoperative data were prospectively collected and retrospectively reviewed for patients who underwent hip arthroscopy at 1 institution between June 2008 and February 2012. Data were analyzed for patients who had adequate radiographs of the pelvis that demonstrated global acetabular retroversion and who were treated with arthroscopic surgery. Complications were tracked in this institution's database. The modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score (HOS)-activities of daily living subscale, and HOS-sport-specific subscale, and VAS were analyzed preoperatively and at latest follow-up. Level of postoperative satisfaction was assessed on a scale of 0 to 10. Pre- and postoperative alpha angle, lateral center-edge angle, anterior center-edge angle, crossover percentage, and Tönnis grade were recorded. Tönnis grade at latest follow-up was utilized to determine progression of osteoarthritis.
Results: A total of 82 hips among 78 patients were identified who met the listed criteria. The mean age of the patients was 23 years, and the mean follow-up was 39 months. These patients showed statistically significant improvement in modified Harris Hip Score (preoperative to ≥2-year follow-up: 65 to 81), Nonarthritic Hip Score (65 to 86), HOS-activities of daily living subscale (69 to 88), HOS-sport-specific subscale (47 to 76), and VAS (5.9 to 2.5) (P < .0001). In terms of satisfaction with the surgery, they had an mean score of 7.4. There were 3 minor complications, none of which required reoperation. One patient underwent hip arthroplasty at 6 months after hip arthroscopy. Fifteen patients had >2-year radiographic follow-up; none of these patients had an increase in Tönnis grade as compared with the preoperative state.
Conclusion: This study demonstrates that hip arthroscopy can successfully treat femoroacetabular impingement associated with a globally retroverted acetabulum at a minimum 2-year follow-up. Survivorship was 99% at 2 years, with 1 patient requiring further surgery in the form of hip arthroplasty. There was no noted progression of Tönnis grade at final follow-up. The procedure was extremely safe, with a minor complication rate of 3.6%.