Improving diagnostic efficiency: Analysis of pelvic MRI versus emergency hip aspiration for suspected hip sepsis

BACKGROUND: Accurately diagnosing and treating childhood hip sepsis is challenging. Adjacent bone and soft-tissue infections are common and can lead to delayed and inappropriate treatment. This study evaluated the effect of early advanced imaging (bone scan, magnetic resonance imaging) in the management of suspected hip sepsis. METHODS: A retrospective review of pediatric patients admitted between 2003 and 2009 with suspected hip sepsis was performed. Patients were classified into 2 categories: group I-immediate hip aspiration or group II-advanced imaging performed before intervention. RESULTS: In total, 130 patients (53 in group I and 77 in group II) were included. No significant differences were found between the groups with regard to laboratory values, temperature, number of anesthetics, and length of hospital stay. However, patients in group I were younger than in group II (5.4 vs. 7.3 y, P=0.02) and more patients in group I were unable to bear weight on the affected limb compared with group II (83% vs. 61%, P=0.009). In group I, 36 patients (68%) had a septic hip compared with 35 patients (45%) in group II. In group I, 16 patients (30%) required reoperation versus 13 (17%) patients in group II. Results from the multivariate analysis demonstrated that reoperation was required 2.8 times (95% confidence interval, 1.12-6.78) more often in group I as compared with group II (P=0.03). CONCLUSIONS: Advanced imaging performed before hip aspiration improves diagnostic efficacy and may decrease the need for reoperation. LEVEL OF EVIDENCE: III.