Inflammatory laboratory markers in periprosthetic hip fractures

The purpose of this study was to determine the prevalence of increased inflammatory laboratory markers in patients with periprosthetic fractures. We also studied the likelihood of the elevation of these values in predicting deep prosthetic joint infection. From 2000 to 2006, 204 patients with periprosthetic hip fractures were treated at our institution. Patients had white blood cell, erythrocyte sedimentation rate, and C-reactive protein obtained on initial evaluation; these were then compared with subsequent hip aspiration, surgical pathology, and deep cultures obtained at the time of revision surgery. A true infection was diagnosed in 11.6%. White blood cell count was increased in 16.2%, erythrocyte sedimentation rate increased in 33.3%, and C-reactive protein increased in 50.5%. The positive elaborate predictive value for these markers for infection was poor (18%, 21%, and 29%, respectively). These findings suggest that increased inflammatory laboratory values in patients with periprosthetic fracture are not good indicators for deep periprosthetic infection and do not necessarily warrant additional evaluations before definitive surgical treatment.