Related Experiment Videos
A composite index for total hip arthroplasty in patients with hip osteoarthritis
Jean Francis Maillefert1, Alice Gueguen, Minh Nguyen
1Institute of Rheumatology, René Descartes University, Cochin Hospital, Paris, France.
Insights
A new composite index for total hip arthroplasty (THA) in hip osteoarthritis (OA) showed high negative predictive values, suggesting it can help identify patients unlikely to need surgery.
Area of Science:
- Orthopedics
- Rheumatology
- Medical Statistics
Background:
- Hip osteoarthritis (OA) is a common cause of pain and disability.
- Total hip arthroplasty (THA) is a common surgical intervention for advanced hip OA.
Purpose of the Study:
- To develop and evaluate a composite index to predict the need for total hip arthroplasty (THA) in patients with hip osteoarthritis (OA).
Main Methods:
- A 3-year longitudinal study of 508 patients with hip OA from 137 centers.
- Collected clinical and radiological data, including joint space width (JSW), pain, and functional indices.
- Used discrete Cox analysis with time-dependent covariates to predict THA occurrence.
Main Results:
- Composite indices incorporating symptomatic, therapeutic, and radiological variables were developed.
- Positive predictive values for THA were moderate (52.9-54.3%).
- Negative predictive values were high (86.7-90.6%), indicating reliability in identifying patients not needing surgery.
Conclusions:
- The developed composite indices have limitations in predicting which patients will undergo THA due to unmeasured factors.
- High negative predictive values suggest these indices are valuable tools for clinicians to identify patients unlikely to require THA.
Objective:
We propose a composite index for considering total hip arthroplasty (THA) in hip osteoarthritis (OA).
Methods:
We carried out a 3 year longitudinal study of patients with painful hip OA from 137 centers. Clinical data were collected at baseline and every 3 months; radiographs were taken at entry and each year. The decision to have surgery was made by the patient, the rheumatologist, and the surgeon, with no reference to outcome measures. Statistical analysis included discrete Cox analysis with time dependent covariates, on 3 month interval grouped data. The dependent variable was THA during the 3 months following the evaluated visit. Time dependent covariates collated at each evaluated visit included radiological joint space width (JSW), percentage decrease in JSW during the year preceding, patient's global assessment. Lequesne index, pain, and nonsteroidal antiinflammatory drug and analgesic intake. We compared 2 analyses differing in symptomatic variables entered: values obtained at a single time point vs mean values between 2 visits at a 3 month interval. Selection of the index was based on the best combination of variables to predict occurrence of THA.
Results:
Of the 508 patients recruited for study, 42 were excluded. During the 3 year followup, 75 patients underwent THA. Symptomatic, therapeutic, and radiological variables were included in the index resulting from the 2 analyses. Based on the selected cutoff, the positive and negative predictive values for occurrence of THA in the 2 years following were 54.3 and 90.6%, respectively (single point model), and 52.9 and 86.7%, respectively (model using mean values of symptomatic variables between 2 visits).
Conclusion:
The poor positive predictive value of the composite indices obtained in this study suggests that there are other unmeasured factors determining access to surgery. On the other hand, the high negative predictive values suggest that these composite measures should be used by clinicians to determine which patients should not be referred to THA.