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To determine the clinical role of rifampin containing antibiotic combination and modified two-stage exchange arthroplasty with a vancomycin loaded polymethylmethacrylate (PMMA) spacer for the treatment of orthopaedic implant related Staphylococcus epidermidis infections, a prospective study was initiated. A total of 10 patients, with a mean age of 59 years (range: 32 to 78 years) were included in the study. The mean follow up was 23.4 months (range: 16 to 36 months). Six patients had an infected hemiarthroplasty of the hip, three had infected total hip arthroplasty, and one had an infected femoral neck fracture with implant failure and pseudoarthrosis. All had culture-proven Staphylococcus epidermidis infections, six of the isolates were methicillin resistant. Following debridement and implantation of a PMMA spacer, a rifampin-vancomycin antibiotic protocol was initiated until the erythrocyte sedimentation rate and C-reactive protein levels were within normal limits. After reimplantation and discharge from the hospital, oral antibiotics with rifampin-ciprofloxacin were continued for three to six months. At the final follow-up none of the patients had any clinical or laboratory signs of infection. Although this study includes a limited number of patients and relatively short-term follow-up the results indicate that in the presence of orthopaedic implant infection with Staphylococcus epidermidis, modified two-stage exchange arthroplasty using a vancomycin-loaded PMMA spacer and a rifampin-containing antibiotic protocol may be beneficial.

In the USA, low velocity gunshot injuries (GSI) account for 13% of all urban spinal injuries, and they have become the second leading cause of all spinal cord injuries. The initial clinical evaluation should assess vascular, visceral, and/or neurological injury. Early imaging studies are required with computerized tomography in addition to plain radiographs to assess accurately the location and extent of the bone injury. The role of steroids is unclear, and if given, should be administered to GSI patients with complete or partial neurological deficit who present within eight hours of injury. The indications for prophylactic antibiotics have not been well established and although recommended, these are deemed essential only in patients with associated visceral perforation. Early surgical exploration is most appropriate to address associated vascular or visceral injury, while spinal decompression does not appear to influence neurological recovery. The majority of GSI spine fractures are stable; instability is usually due to ill-advised decompression of cervical spine GSI. Retained bullet fragments are rarely problematic; lead toxicity can occur due to missile contact with the synovial fluid, disc space, or contact with a pseudocyst.

Treatment of orthopaedic device related infections with antibiotics alone generally has been thought to be inadequate. A rabbit model was used to compare the efficacy of 4 different antibiotic regimens for treating orthopaedic device related infection caused by slime producing Staphylococcus epidermidis. After bacterial inoculation of a hole drilled through the intercondylar notch, a stainless steel screw was placed into the femur. Two weeks later, rabbits were randomized to receive a 2-week course of antibiotics: (1) 9 rabbits received vancomycin alone; (2) 10 rabbits received minocycline alone; (3) 10 rabbits received vancomycin plus rifampin; and (4) 10 rabbits received minocycline plus rifampin. Quantitative bone cultures were performed, and antibiotic levels in serum, bone, and biofilm were determined. Despite high levels of vancomycin in biofilm, infection was never cured by vancomycin alone and was eradicated in only 20% of rabbits that received minocycline alone. The highest cure rate (90%) was achieved with the combination of vancomycin and rifampin, whereas the combination of minocycline and rifampin yielded a cure rate of 70%. These results encourage the clinical evaluation of the combination of vancomycin and rifampin in patients in whom infected orthopaedic device cannot be removed.

From 1983 to 1992, nine above-knee amputations were performed in eight patients for complications after total knee arthroplasty. The mean time from the initial knee replacement to amputation was 9.7 years. The average age of the four men and four women was 72 years. Eight knees had chronic infection and one had intractable pain after four revision attempts for aseptic loosening. Most patients had two revision arthroplasties after the original implant. In this series, the common factors that lead to amputation were multiple revision attempts in the presence of chronic infection, severe bone loss, and intractable pain. Earlier consideration of arthrodesis rather than multiple revision attempts is recommended to avoid such a poor outcome.