Rates and Risk Factors of Conversion Hip Arthroplasty After Closed Reduction Percutaneous Hip Pinning for Femoral Neck Fractures-A Population Analysis.

Background: Closed reduction with percutaneous pinning (CRPP) for nondisplaced or valgus impacted femoral neck fractures is a relatively low-risk operation that can produce excellent union rates in some patients; however, failure can occur in selected patients requiring conversion to arthroplasty. The primary aim of this study was to perform a population-level analysis to determine the rate and timeframe of conversion from CRPP to total hip arthroplasty (THA) or hemiarthroplasty.
Methods: The PearlDiver database was queried from 2007-2015 for all patients who underwent CRPP for a femoral neck fracture. Survival analysis was used to evaluate the rate of conversion of CRPP to hemiarthroplasty or THA. Risk factors for conversion arthroplasty were identified using a multivariable cox proportional hazards model that included patient demographics and comorbidities.
Results: There were 5122 patients in the Humana database and 4840 patients in the Medicare database that were included in analysis. At 5 years after CRPP, the conversion rate was 10.0% in the Medicare patients and 10.8% in the Humana patients. Risk factors for undergoing conversion from CRPP to arthroplasty in the Medicare cohort included preexisting diagnoses of pulmonary and/or circulatory comorbidities, peripheral vascular disease, hypertension, hypothyroidism, and metastatic cancer. In the Humana cohort, the only risk factors were male gender and acute blood loss anemia.
Conclusion: Although CRPP remains a successful operation in elderly patients and patients with certain comorbidities, failure of CRPP for the treatment of a femoral neck fracture is high at approximately 10%-11%, which is much higher than reported failure rates for THA in the same population. Patients with femoral neck fractures being considered for CRPP should be counseled about the possibility of further surgery.
(Copyright © 2017 Elsevier Inc. All rights reserved.)