Use of antibiotic-loaded polymethyl methacrylate beads in the management of musculoskeletal sepsis--a retrospective study.

OBJECTIVE: To assess the use of antibiotic-loaded polymethyl methacrylate beads in the management of chronic osteomyelitis of different aetiologies: infected osteosynthesis, infected open fractures, and haematogenous osteomyelitis.
METHODS: Records of 49 patients with chronic osteomyelitis who were treated at Department of Orthopaedics, Kasturba Medical College, from 1995 to 1999 were studied retrospectively. The diagnosis of chronic osteomyelitis was made on the basis of clinical and radiographic features. Of the 49 patients, 4 had haematogenous osteomyelitis, which later proved to be tuberculosis, and were thus excluded. Antibiotic-loaded acrylic beads were implanted in the remaining patients after thorough debridement. The implant was removed primarily in 16 patients with infected osteosynthesis, who then underwent decompression and sequestrectomy. All wounds were closed primarily. Peri-operative antibiotics were given for 7 days. Beads were removed at the end of 3 weeks followed by bone grafting in 26 patients. Patients were followed up for an average period of 3.7 years.
RESULTS: The infective organisms were sensitive to gentamycin in 26 cases and resistant in 19 cases; 14 cases were sensitive to cefuroxime, 11 to cloxacillin, 8 to ampicillin, and 5 to cotrimoxazole. Seven cases were resistant to all antibiotics tested. Of the 19 patients with gentamycin-resistant infection, only one had a poor result. No adverse systemic side-effects such as ototoxicity or nephrotoxicity were seen. Infection did not recur in 39 patients, but 6 patients had low-grade persistent infection at the last follow-up visit.
CONCLUSION: In chronic infections, especially those following osteosynthesis, antibiotic beads are a valuable adjuvant. The most valuable advantage is that the wound can be closed primarily, thereby reducing the incidence of nosocomial infections and requirement of nursing care.