Medium-term curative effect of extensively coated non-modular femoral stem in two-stage infection revision after joint replacement

Abstract

Objective To determine medium-term curative effect of extensively coated non-modular femoral stems in twostage infection revision after joint replacement. Methods We retrospectively analyzed 33 patients (33 hips) who had a two-stage infection revision after total hip replacement arthroplasty from March 2005 to December 2006. Among of them, there were 20 men (20 hips) and 13 women (13 hips). Their mean age was 66.1±7.2 years with a range from 52 to 80. The two-stage revision protocol consisted of joint prosthesis taken out in the first stage, thorough debridement, hand-molded antibiotic bone cement spacer, and two-stage joint revision after anti-infective therapy. Anti-infective therapy included intravenous antimicrobial therapy for 4 weeks and oral antibiotics for 6 weeks. Harris hip score (HHS) was used to evaluate functions of hip joint. X-ray films were used to perform clinical and radiological evaluations of prosthesis stability, displacement and looseness. Reinfection criteria were the same as the criteria used to diagnose the joint infection. Results Follow-up visit was carried out for all patients for 5-9 years (6.1±1.7 years on the average). No infection or prosthesis looseness happened after two-stage revision. Microculture of samples taken during two-stage revision or pathological examination was negative. Harris hip joint score rose to 89.1±8.5 in the last follow-up visit from preoperative 42.3±6.5. 30 patients achieved stable bone ingrowths and the remaining three had stable fibrous ingrowths. Impacted bone graft at acetabulum side for 11 patients and all impacted bone graft in marrow cavity were fused well with the host bones. Allogeneic cortical bone plate grafts were used in 10 hips on the femoral side. Nine of these cortical bone plates fused with the host bones after postoperative 1 year, whereas one fused after 2 years. Conclusion Using extensively coated nonmodular femoral stems combined with intramedullary allograft in two-stage revision for treating infection can achieve satisfactory medium-term survival rate of prosthesis and infection clearance rate. Key words: Arthroplasty, replacement, hip; Prosthesis-related infections; Reoperation