Infected hip hemiarthroplasties and total hip arthroplasties: Differential findings and prognosis

Objectives: Infected hip hemiarthroplasties (HHA) are classically analyzed along with infected total hip arthroplasties (THA), but patients with either one or other device are different. We describe the clinical presentation, etiology and prognosis of infected HHA compared with infected THA.

Methods: Comparative study of patients with infected HHA and THA from a prospective database of prosthetic joint infection (PJI) cases in our hospital (2003-2011), focusing on patients managed with debridement, antibiotics and implant retention (DAIR).

Results: 210 episodes of hip-PJI (age 74 years, 63% women): 62 (39%) HHA and 148 (61%) THA. HHA-patients were older and had more comorbidities. Late-chronic and hematogenous infections were more frequent in THA. 123 (59%) patients were managed with DAIR: 72 THA and 51 HHA. Staphylococcus aureus was more frequent in THA (44% vs 26%, p = 0.032), while Gram-negative bacilli were more prevalent in HHA (73% vs 51%, p = 0.018), with a higher prevalence of fluoroquinolone-resistance in cemented-HHA. Overall failure was 37%, with no significant differences among groups. A higher mortality was observed in HHA cases (21% vs 4%, p = 0.005), particularly in cemented-HHA.

Conclusion: Infected THA and HHA have different characteristics, etiology and prognosis. Overall failure was similar, probably balanced by different predictors among groups, but mortality was higher among cemented-HHA.