Risk of failure of primary hip arthroscopy-a population-based study

Abstract

The aims of this study are (i) to report on the rates of subsequent surgery following hip arthroscopy and (ii) to identify prognostic variables associated with revision surgery, survival rates and complication rates. The Statewide Planning and Research Cooperative System database, a census of hospital admissions and ambulatory surgery in New York State, was used to identify cases of primary hip arthroscopy. Demographic information and rates of subsequent revision hip arthroscopy or arthroplasty were collected. The risks were modeled with use of age, sex, procedure and surgeon volume as risk factors. Survival analyses were also performed, and 30-day complication was recorded. We identified 8267 procedures in 7836 patients from 1998 to 2012. Revision surgery occurred in 1087 cases (13.2%) at a mean of 1.7 ± 1.6 (mean ± SD) years. Revision arthroscopy accounted for 311 cases (3.8%), and arthroplasty for 796 (9.7%) cases. Survival analysis showed a 2-year survival rate of 88.1%, 5-year of 80.7% and 10-year of 74.9%. Regression analysis revealed that age >50 years [hazard ratio (HR) 2.09; confidence interval (CI) 1.82-2.39, P < 0.01] and a diagnosis of osteoarthritis (HR 2.72; CI 2.21-3.34, P < 0.01) were associated with increased risk of re-operation. Labral repair was associated with a lower risk of re-operation (HR 0.71; CI 0.54-0.93, P = 0.01). Finally, higher surgeon volume (>164 cases/year) resulted in a lower risk of re-operation versus lower volume (<102 cases/year) (HR 0.42; CI 0.32-0.54, P < 0.01). The 30-day complication rate was 0.2%. Older age and pre-existing osteoarthritis increased the likelihood of re-operation following hip arthroscopy, whereas performing a labral repair and having the procedure performed by a higher-volume surgeon lowered the risk of re-operation.

Fig. 1.

Annual volume of surgeons and centers performing hip arthroscopy.

Fig. 2.

Annual volume of primary hip arthroscopy cases.

Fig. 3.

Kaplan–Meier survival curve for primary hip arthroscopy over a 10-year time period. Failure was defined as the need for revision hip arthroscopy or conversion to total hip arthroplasty or hip resurfacing. x-axis represents time to failure in years, y-axis is the cumulative survival rate.

Fig. 4.

Kaplan–Meier survival curve for primary hip arthroscopy over a 5 year time period for the different volume-strata identified with SSLR threshold-analysis model. Failure was defined as the need for revision hip arthroscopy or conversion to total hip arthroplasty or hip resurfacing. x-axis represents time to failure in years, y-axis is the cumulative survival rate.