ObjectiveTo summarize the experience in the treatment of infection after limb salvage surgery for malignant tumor around knee joint, and explore the risk factor related to infection after limb salvage surgery.MethodsA clinical data of 212 patients with malignant tumor around the knee joint underwent limb salvage surgery between January 2008 and December 2017 were retrospectively analyzed. Among them, 14 cases had infection after limb salvage surgery. Two cases of acute infection were treated with sensitive antibiotics; 12 cases of chronic infection were treated with debridement and antibiotic bone cement occupying device implantation in the first stage, and prosthesis revision (8 cases), knee joint fusion (2 cases), or amputation (2 cases) in the second stage after infection control. The age, gender, preoperative chemotherapy cycle, bone marrow suppression, serum albumin, hemoglobin, operation time, postoperative drainage time, and blood transfusion volume were analyzed to screen the risk factors related to infection after limb salvage surgery. The infection and tumor recurrence were observed, and the limb function was evaluated by Enneking scoring system.ResultsThe univariate analysis showed that the preoperative chemotherapy cycle, bone marrow suppression, operation time, and postoperative drainage time were the influencing factors of postoperative infection (P<0.05). Multivariate analysis showed that the operation time, preoperative chemotherapy cycle, and postoperative drainage time were risk factors of postoperative infection (P<0.05). Among the 14 patients, 1 patient died of traffic accident at 6 months after the second stage operation, and 13 patients were followed up 12.2-48.0 months (mean, 19.9 months). Two cases of acute infection cured. Among the 11 patients with chronic infection, 2 cases of subluxation of the antibiotic bone cement occupying device after the first stage operation occurred; 9 cases of infection cured and 2 cases recurred. At 12 months after operation, except 1 case died by accident, the Enneking scores of the other 13 patients were 12-26, with an average of 20. At last follow-up, 1 case of lung metastasis was still alive, and no tumor metastasis or recurrence was found in the rest.ConclusionThe time of limb salvage surgery, preoperative chemotherapy cycle, and drainage time after limb salvage surgery are the risk factors of infection after limb salvage surgery. Early etiological examination and drug sensitivity test is the key to the treatment of infection. One-stage debridement combined with antibiotic bone cement occupying device can effectively cure infection and save patients’ limbs.