2021 ISAKOS Biennial Congress Paper
Risk Of Conversion To Arthroplasty Following Hip Arthroscopy: Validation Of A Published Risk Score Using An Independent, Prospectively Collected Database
Mario Hevesi, MD, PhD, Rochester, MN UNITED STATES
Devin Leland, MD, Rochester, MN UNITED STATES
Philip Joseph Rosinsky, MD, Skokie, IL UNITED STATES
Ajay C. Lall, MD, MS, FAAOS, Paramus, New Jersey UNITED STATES
Benjamin G. Domb, MD, Chicago, IL UNITED STATES
David E. Hartigan, MD, Robbinsdale , Mn UNITED STATES
Bruce A. Levy, MD, Orlando, Florida UNITED STATES
Aaron J. Krych, MD, Rochester, MN UNITED STATES
Mayo Clinic, Rochester, MN, UNITED STATES
FDA Status Not Applicable
Summary
This external validation study supports that the THA risk score proposed by Redmond et al. accurately predicts hip arthroscopy patients converting to subsequent arthroplasty, with satisfactory discriminatory, Receiver-Operator Curve (ROC), and Brier score calibration characteristics.
Abstract
Background
Hip arthroscopy is rapidly advancing and increasingly commonly performed. The most common surgery following arthroscopy is total hip arthroplasty (THA), which unfortunately occurs within 2 years of arthroscopy in up to 10% of patients. Predictive models for conversion to THA such as that proposed by Redmond et al. have potentially substantial value in preoperative counseling and decreasing early arthroscopy failures, however, these models need to be externally validated to demonstrate broad applicability.
Purpose
To utilize an independent, prospectively collected database to externally validate a previously published risk calculator by determining its accuracy in predicting conversion of hip arthroscopy to THA at minimum 2-year follow-up.
Study Design: Cohort Study, Level of Evidence, 3.
Methods
Hip arthroscopies performed at a single center November 2015–March 2017 were reviewed. Patients were assessed pre/intra-operatively for components of the THA risk score studied, namely age, modified Harris Hip Score (mHHS), lateral center edge angle, revision procedure, femoral version, and femoral/acetabular Outerbridge score, and followed for a minimum of 2 years. Conversion to THA was determined along with the risk score’s receiver-operator curve (ROC) and Brier score calibration characteristics.
Results
187 patients (43M, 144F, age: 36.0 ± 12.4 years) underwent hip arthroscopy and were followed for mean of 2.9 ± 0.85 years (Range: 2.0–5.5), with 13 patients (7%) converting to THA at a mean of 1.6 ± 0.9 years. Patients who converted to THA had a mean predicted arthroplasty risk of 22.6 ± 12.0% compared to patients who remained arthroplasty free with a predicted risk of 4.6 ± 5.3% (p<0.01). The Brier score for the calculator was 0.04 (p=0.53), which was not statistically different from ideal calibration, and the calculator demonstrated a satisfactory AUC of 0.894 (p<0.001).
Conclusion
This external validation study supports that the THA risk score proposed by Redmond et al. accurately predicts hip arthroscopy patients converting to subsequent arthroplasty, with satisfactory discriminatory, ROC, and Brier score calibration characteristics. These findings are important in that they provide surgeons with validated tools to identify patients at greatest risk for failure following hip arthroscopy and assist in patient counseling and decision making.