Minimum 2-Year Outcomes of Hip Arthroscopic Surgery in Patients With Acetabular Overcoverage and Profunda Acetabulae Compared With Matched Controls With Normal Acetabular Coverage
Background: Advancements in instrumentation and techniques have extended the scope of hip arthroscopic surgery to treat complex osseous deformities that were previously best addressed with an open approach. Global pincer-type femoroacetabular impingement is an example of an abnormality requiring osseous correction with a technically challenging access point.
Purpose: To report on the patterns of clinical presentation and intra-articular derangements, radiological associations, and minimum 2-year outcomes after hip arthroscopic surgery in patients with a lateral center edge angle (LCEA) >40° and profunda acetabulae in comparison with matched controls with normal acetabular coverage.
Study design: Cohort study; Level of evidence, 3.
Methods: Data were collected on all patients undergoing hip arthroscopic surgery during the study period from April 2008 to April 2013. All patients who had undergone hip arthroscopic surgery for symptomatic labral tears not responsive to a minimum of 3 months of physical therapy with both an LCEA >40° and profunda acetabulae, as defined by the ilioischial line lateral to the medial border of the teardrop, and without a history of hip surgery or hip conditions were included. This group was matched in a 1-to-1 ratio with a control group that had also undergone the arthroscopic management of symptomatic labral tears refractory to a minimum of 3 months of physical therapy with an LCEA between 25° and 40° according to age within 3 years, sex, body mass index category, Tönnis grade, labral treatment, and capsular treatment. Range of motion, impingement signs, and radiographic indices of coverage and version were recorded for each group. Four patient-reported outcome (PRO) scores, the visual analog scale (VAS) for pain, patient satisfaction, revision hip arthroscopic surgery, and conversion to total hip arthroplasty (THA) were also recorded.
Results: Thirty-nine patients met the inclusion criteria for the study (overcoverage) group, of which 36 (92.3%) patients had a minimum 2-year follow-up; 215 patients satisfied the inclusion criteria for the control (normal coverage) group, of which 183 (85.1%) had a minimum 2-year follow-up. Thirty-six patients were matched in each group using the above criteria. There was no difference with respect to range of motion and impingement signs between the groups. The study group had significantly higher radiological markers of overcoverage but not retroversion compared with the control group. The study group had a significantly higher incidence of Seldes type 2 tears compared with the control group: 50.0% versus 19.4%, respectively ( P = .013). Both groups demonstrated significant improvements in the mean scores of all PROs, but the study group had a lower magnitude of improvement for all the PROs compared with the control group, with the modified Harris Hip Score (mHHS) achieving statistical significance: 13.5 versus 21.7 points, respectively ( P = .032). The study group had a significantly lower mean patient satisfaction score compared with the control group: 6.61 versus 7.91, respectively ( P = .019). The study group also had a significantly higher incidence of conversion to THA compared with the control group: 4 versus 0, respectively ( P = .040).
Conclusion: Hip arthroscopic surgery for the management of symptomatic labral tears in patients with combined overcoverage and coxa profunda is associated with improvements in patient outcomes and pain at a minimum 2-year follow-up. However, the degree of improvement is of lower magnitude compared with a matched cohort with normal coverage undergoing the arthroscopic management of symptomatic labral tears. While hips with lateral overcoverage combined with coxa profunda may have a smaller potential for improvement compared with hips with normal coverage, this type of osseous morphology is still repairable with arthroscopic treatment.