Megaendoprostheses in the management of malignant tumors of the lower extremities—risk factors for revision surgery

ABSTRACT: BACKGROUND: Improved oncological and surgical measures now enable curative treatment of malignant lower extremity tumors in majority of cases. Complication rates associated with surgical resection of lower extremity tumors and replacement with megaendoprostheses are high. The aim of this study was to identify risk factors that predispose to revision surgery following the use of megaimplants in curative treatment of malignant tumors of the lower extremities. METHODS: this retrospective study included patients aged ≥ 18 years who underwent implantation of a megaendoprosthesis for tumors or metastatic lesions of the lower extremities between January 2010 and December 2020. Baseline characteristics and information on adjuvant treatment, hospitalization time, comorbidities, mobility, complications, and revision surgery were considered. Primary outcomes were revision surgery and reasons for revision. Secondary outcomes were in-hospital complications and the duration of hospitalization. RESULTS: Fifty-four patients (48% female, age 63 years, SD 15) were available for final analysis. Surgeries were performed at hip level in 37 patients (68.5%) and at knee level in 17 patients (31.5%). Revision for wound-related causes was performed in 12 cases (22.2%), with microbiological proof of infection in 8 cases (14.8%). Revision for hip joint instability was carried out in 4 cases (7.4%) and for disconnection between components of the megaimplant in 2 cases (3.7%). Those patients requiring a wound-related revision had undergone a longer primary surgical intervention than those who required an implant-related revision (276 vs 134 min, p = .002). Wound drains after the primary implantation remained longer in situ in patients who later required revision surgery for wound-related complications (5 vs 3 days, p = .020). An ASA > 3 was associated with an increased likelihood for in-hospital complications in general (p = .041), and in-hospital death in particular (p = .012). CONCLUSIONS: The management of malignant tumors of the lower extremities with megaendoprostheses is associated with a high rate of wound-related complications. Swift surgical performance and early postoperative removal of wound drains minimize the risk of complications in general and the necessity of revision surgery in particular. Patients with more comorbidities were more likely to suffer in-hospital complications.