The infected hip: telltale signs and treatment options.

The diagnosis of deep infection after total hip arthroplasty may not be obvious. Mild pain may be the only symptom. Normal radiographs do not exclude infection. Screening blood tests include the erythrocyte sedimentation rate and the C-reactive protein. If either test is elevated with a painful total hip, aspiration of the joint is efficacious. Aspiration remains the cornerstone for the diagnosis and treatment of infection. Intraoperative frozen sections can also be of value in the diagnosis of infection; however, this method is dependent on tissue sampling. A 2-stage revision remains the criterion standard for treatment. An antibiotic-impregnated cement spacer can deliver a high concentration of antibiotic to the infected space, maintain soft tissue tension, and provide better function than a resection arthroplasty. Direct exchange is rarely indicated today.