Bone transport through an induced membrane in the management of tibial bone defects resulting from chronic osteomyelitis

Wide resection of infected bone improves the odds of achieving remission of infection in patients with chronic osteomyelitis. Aggressive debridement is followed by the creation of large bone defects. The use of antibiotic-impregnated PMMA spacers, as a customized dead space management tool, has grown in popularity. In addition to certain biological advantages, the spacer offers a therapeutic benefit by serving as a vehicle for delivery of local adjuvant antibiotics. In this study, we investigate the efficacy of physician-directed antibiotic-impregnated PMMA spacers in achieving remission of chronic tibial osteomyelitis. This retrospective case series involves eight patients with chronic osteomyelitis of the tibial diaphysis managed with bone transport through an induced membrane using circular external fixation. All patients were treated according to a standardized treatment protocol. A review of the anatomical nature of the disease, the physiological status of the host and the outcome of treatment in terms of remission of infection, time to union and the complications that occurred was carried out. Seven patients, with a mean bone defect of 7 cm (range 5-8 cm), were included in the study. At a mean follow-up of 28 months (range 18-45 months), clinical eradication of osteomyelitis was achieved in all patients without the need for further reoperation. The mean total external fixation time was 77 weeks (range 52-104 weeks), which equated to a mean external fixation index of 81 days/cm (range 45-107). Failure of the skeletal reconstruction occurred in one patient who was not prepared to continue with further reconstructive surgery and requested amputation. Four major and four minor complications occurred. The temporary insertion of antibiotic-impregnated PMMA appears to be a useful dead space management technique in the treatment of post-infective tibial bone defects. Although the technique does not appear to offer an advantage in terms of the external fixation index, it may serve as a useful adjunct in order to achieve resolution of infection.