Abstract
Objectives:
To analyze predictors of clinical failure as defined by revision hip arthroscopy or conversion to total hip arthroplasty (THA) as well as predictors of inferior outcomes defined as the not reaching Minimally Clinical Important Difference (MCID) or Patient Acceptable Symptomatic State (PASS) for Hip Outcome Score-Activities of Daily Living Subscale (HOS-ADL).
Methods:
Prospective data on all patients who underwent primary hip arthroscopy with routine capsular closure for the treatment of femoroacetabular impingement syndrome (FAIS) by a single, fellowship-trained surgeon between January 2012 and November 2015 were collected and analyzed. Inclusion criteria consisted of clinical and radiographic diagnosis of symptomatic FAIS, failed conservative management, and undergoing hip arthroscopy to correct FAIS with a minimum of two-year follow-up. Exclusion criteria consisted of prior ipsilateral hip surgery and hip arthroscopy for an indication other than FAIS. Baseline demographic data and radiographic parameters were collected and patient-reported outcomes (PROs) were obtained at baseline and at a minimum of two-years postoperatively. Rates of clinical failure and inferior clinical outcomes were recorded at a minimum of two-years postoperatively then stepwise linear regression was used to identify patient-related and imaging-related factors as predictors of each, respectively.
Results:
Out of 1,161 eligible patients, 949 (81.7%) completed PROs at a minimum of two-years postoperatively. The average age was 32.8 ± 12.4 years with a mean BMI of 25.4 ± 10.7 kg/m2. The overall clinical failure rate was 2.2% (n=21) including eleven cases of revision hip arthroscopy and eleven cases of conversion to THA (one patient underwent revision then subsequent THA). The inferior clinical outcome group consisting of patients who failed to reach MCID for HOS-ADL included164 patients while those who failed to reach PASS for HOS-ADL included 353 patients. In the regression model, poor articular cartilage, hypertension, lateral rim impingement on physical exam, history of back pain/spine pathology, limp on presentation, decreased daily physical activity, greater preoperative alpha angle, weakness in abduction with knees extended, and prolonged symptom duration were predictive of clinical failure (all p-values<0.05). Predictors of failing to reach MCID for HOS-ADL included: prolonged symptom duration, history of back pain/spine pathology, Tonnis grade >1, being a current/former smoker, pain with ischial palpation, lateral rim impingement, snapping iliotibial band, and pain with resisted sit-up and over the greater trochanter. Predictors of failing to reach PASS for HOS-ADL included: prolonged symptom duration, decreased daily physical activity, workman’s compensation, history of anxiety and/or depression, snapping iliotibial band, limp on examination, and pain with palpation of the spine/sacroiliac joint (all p-values<0.05).
Conclusion:
The clinical failure rate of hip arthroscopy may be lower than previously reported. Reoperation is predicted by medical comorbidity, lack of preoperative athletic activity, and multiple positive physical exams. Inferior clinical outcomes are predicted by prolonged symptom duration, back pain, being a current/former smoker, a history of a psychiatric comorbidity, as well as numerous signs on physical examination.