Causes, risk factors, and costs associated with ninety-day readmissions following primary total hip arthroplasty for femoral neck fractures.

INTRODUCTION

Risk factors associated with primary THA readmissions have not yet been thoroughly analyzed when stratified by underlying indication. Given that a majority of THAs are done electively in the context of osteoarthritis (OA), it remains to be explored whether or not THAs performed non-electively in the trauma setting have different readmission patterns. Therefore, the aims of this study were to identify: 1) causes of readmissions; 2) patient-related risk-factors for readmissions; and 3) costs associated with the reasons for readmissions.

MATERIALS AND

METHODS

Patients who sustained a femoral neck fracture and underwent primary THA from 2005 to 2014 were identified. Those subsequently readmitted within 90-days following the procedure comprised the study cohort whereas those not readmitted served as the comparison cohort. Primary outcomes included identifying causes of readmissions, identifying patient-related risk-factors associated with readmissions and determining healthcare expenditures associated with the different readmission etiologies. A regression analysis was used to calculate the odds (OR) for readmissions. A p-value less than 0.01 was considered to be statistically significant.

RESULTS

The regression model demonstrated the greatest patient-related risk factors included: electrolyte and fluid disorders (OR: 1.80, p < 0.0001), morbid obesity (OR: 1.60, p < 0.0001), pathologic weight loss (OR: 1.58, p < 0.0001), congestive heart failure (OR: 1.41, p < 0.0001), were the leading risk factors for readmissions. Pulmonary-related causes ($42,357.71) of readmission were the leading driver of costs of care.

CONCLUSION

Orthopaedic surgeons should identify and optimize pre-operative management of patient-related risk factors that increase readmissions following primary THA for femoral neck fractures. Additionally, pulmonary-related causes of readmission lead to the highest costs of care.

LEVEL OF EVIDENCE: III.