ToolsCalculators
RAPID Score for Acetabular Chondrolabral Disruption
Preoperative estimate of high-grade acetabular cartilage damage before hip arthroscopy.
RAPID Score for Acetabular Chondrolabral Disruption
Sex
Tonnis grade (radiographic osteoarthritis)
Preoperative AP pelvis radiograph.
Cam morphology (alpha angle >55 degrees on Dunn view)
Result0 points
Low predicted probability of grade 3-4 (high-grade) acetabular chondrolabral disruption at arthroscopy.
- Sex
- Female
- Tonnis grade points
- 0
- Cam morphology
- Absent
- Reported risk of high-grade damage
- ~10.5 %
When to use
- Counseling patients preoperatively about the likelihood of high-grade (ALAD grade 3-4) acetabular cartilage damage before hip arthroscopy for femoroacetabular impingement or labral tear.
- Supplementing indeterminate or artifact-limited MRI/MR arthrogram findings when planning for possible cartilage procedures (e.g., microfracture).
Formula
RAPID score (0-5) = points for male sex (1) + Tonnis grade (grade 0 = 0, grade 1 = 2, grade 2 = 3) + cam morphology, alpha angle >55 degrees on Dunn view (1). Derived by multivariable stepwise logistic regression (Akaike information criterion) from 652 primary hip arthroscopies; validated prospectively in 167 additional cases.
Pearls and pitfalls
- In the derivation and validation cohorts, risk of high-grade damage rose from about 10.5% at 0 points to about 88.0% at 5 points (AUC 0.75 and 0.76, respectively).
- A score of 5 had 99.1% specificity for high-grade damage in the original cohort.
- Age and BMI were significant on univariate analysis but were not retained in the final multivariable model.