What Are the Risk Factors and Management Options for Infection After Reconstruction With Massive Bone Allografts?

Abstract

Background Massive bone allografts have been used for limb salvage of bone tumor resections as an alternative to endoprosthesis, although they have different outcomes and risks. The use of massive bone allografts has been thought to be associated with a high risk for infection, and there is no general consensus on the management of this complication and final outcome. Because infection is such a devastating complication of limb salvage, at times leading to loss of a limb, recognizing the risk factors for infection and the results of treatment is important. Questions/purposes The purposes of this study were (1) to analyze the frequency of infection in a group of patients treated with massive bone allografts; (2) to analyze risk factors such as age, sex, affected bone, type of reconstruction, operative room used, primary or revision procedure, length of postoperative antibiotic administration, and use of chemotherapy; and (3) to determine the likelihood that treatment of an infected allograft will result in a successful reconstruction.Methods We retrospectively analyzed the records of patients treated with massive bone allografts for a benign or malignant bone tumor or as a revision for a previous limb salvage procedure between 1985 and 2011. During this period, 673 patients were reconstructed with massive bone allografts in long bones, which included 272 osteoarticular, 246 intercalary, and 155 allograft-prosthetic composite reconstructions. Using a chart review, we ascertained the frequency of infection and reoperations after the treatment of infected allografts. Minimum followup was 2 years unless death occurred earlier (mean, 106 months; range, 6-360 months), and no patient was lost to followup. The selected variables were analyzed using multivariate logistic regression to identify risk factors for infection. We analyzed survivorship free of infection as the endpoint. Results During followup, 60 patients (9%) had a bacterial infection of the allograft with a survivorship free from infection of 92% at 5 years (95% confidence interval [CI], 90%-94%) and 91% at 10 years (95% CI, 89%-93%). We found that tibia allografts (p\0.001; odds ratio [OR], 3.17; 95% CI, 1.80-5.60), male patients (p \ 0.029; OR, 1.92; 95% CI, 1.08-3.49), procedures performed in a conventional operating room (p \ 0.002; OR, 3.15; 95% CI, 1.58-6.62), and the use of longer periods of postoperative antibiotics (p \ 0.041; OR, 2.25; 95% CI, 1.02-4.88) were patient factors associated with a greater risk of infection. In 11 patients (18%, 11 of 60 infections) the infection was controlled with antibiotics and surgical débridement; however, in 49 patients (82%, 49 of 60 infections), this approach failed, so the allograft was removed and a temporary cement spacer with antibiotic was implanted to control the infection. Forty-one patients subsequently had the spacer removed and were reconstructed after infection control with another bone allograft in 24 and an endoprostheses in 17. Four patients underwent an amputation

CORR Insights®: What Are the Risk Factors and Management Options for Infection After Reconstruction With Massive Bone Allografts?

“…The crude infection rate of 9% at 10 years of followup found in the study by Aponte-Tinao and colleagues [1] remains consistent with previously published estimates in patients treated with bulk allograft infection, which range from 8.5% to 13% [5,6]. Infections frequently coexist with, or predispose to, the other dreaded allograft complications of fracture and nonunion.…”

“…Aponte-Tinao and colleagues [1] interestingly noted that prolonged postoperative antibiotic administration did not protect patients from infection, and may have actually resulted in a higher risk of infections in treated patients. However, there is a growing body of evidence, particularly within the spine literature, that topical antibiotic powder placed at the conclusion of procedures may markedly reduce postoperative infections [3].…”

“…These need not be randomized (although that would, naturally, be great), but should be large, and therefore likely should include patients from multiple centers. This aspect is important because, in spite of the much smaller number likely necessary to demonstrate important results given the high baseline infection rate, other aspects such as tibial allograft site and patient gender [1] may also impact the risk of infection. Simple univariate analysis, therefore, remains unlikely to be convincing and definitive unless the compared groups are both large and similar.…”

Salvage of infected proximal tibial tumour prosthesis using vacuum assisted closure (VAC) in seven patients

“…The proximal tibia is the second most common site of both benign and malignant bone tumours (second to distal femur). [1][2][3] The commonest benign tumour in proximal tibia is giant cell tumour and commonest malignant tumour is osteosarcoma. The treatment of such tumours has changed drastically from limb ablation (above knee amputation) to limb salvage (wide resection and endoprosthetic reconstruction using custom modular prosthesis±neo-adjuvant chemotherapy).…”

Editorial—Going Global: CORR ® Best-paper Awards for China and Latin America in 2015

“…This is an enormous clinical problem, and we congratulate the authors on a job well done. Through careful data collection and analysis, the authors determined that surgical débridement of the infected bone allograft generally was not sufficient treatment, and that complete resection generally was called for [1]. In those patients whose grafts were resected, repeat reconstruction with allograft proved to be a dangerous choice, and the authors conclude that alternatives-perhaps including endoprosthetic reconstruction-might be better.…”