Abstract:Objective:To evaluate whether the microbial culture results of fluid or tissue obtained from the affected joint in patients with chronic periprosthetic joint infection (PJI) after total hip arthroplasty (THA) affect the effect of two-stage revision surgery. Methods:A retrospective study including 48 patients who underwent two-stage revision surgery with chronic PJI after THA from General Hospital of Beijing Military Region was conducted. The first stage comprised prosthesis extraction,radical debridement and insertion of vancomycin-loaded cement hip spacer. After eradicating the infection,a cementless THA was implanted in the second stage. Postoperatively,all patients were received sensitive antibiotics via intravenous drip for 6 weeks. Patients were assessed for infection control time,infection recurrence,pain evaluation[visual analog scale(VAS)]and hip joint function evaluation(Harris Hip score). X-ray photograph was routinely performed. Results:The numbers of microorganism in the culture-negative (CN)group and bacteria culture-positive(CP)group were 13 and 35,respectively. After debridement revision in the first stage,infection was controlled in all patients. The time for controlling infection in the CN group was longer than that in the CP group[(119.3 ± 30.1)d vs. (98.4 ± 25.9)d,P=0.03]. The average duration of follow-up was 29.6 (range,9~49)months in outpatient department. At last follow-up,Harris hip score and pain VAS score were significantly improved compared with preoperation in all patients. Compared with the CP group,patients in the CN group were with a higher pain VAS score[2.8 ± 1.6 vs. (1.8 ± 1.2),P=0.03],a lower Harris function score[(79.1 ± 9.1) vs. (85.6 ± 7.1),P=0.01]as well as excellent and good rate[53.8% vs. 85.7%,P=0.04]. There were 2 cases of recurrence respectively in the CN group and CP group,but no statistical difference of recurrence rate was observed between the two groups[15.4% vs. 5.7%,P=0.62]. Conclusion:Satisfactory outcomes can be obtained with two-stage revision using vancomycin-loaded cement hip spacers and cementless implants for prosthetic hip joint infections. However,microbial culture results may affect the efficacy of two-stage revision in PJI patients,patients with a culture negative result may get a poor prognosis. The improvement of the detection rate of microoganism and application sensitive antibiotics may have a profound meaning on the effect of PJI.