Clinically significant thromboembolic disease in orthopedic oncology: an analysis of 986 patients treated with low-molecular-weight heparin.

Background and Objectives: Thromboembolic risk in orthopedic oncology is high due to several factors. The aim of this study was to assess clinically significant thromboembolic disease in 986 patients operated on with a prosthetic reconstruction of the lower limbs after the resection of bone tumors and prophylactically treated with low-molecular-weight heparin (LMWH). Methods: Between 1983 and 2006, 986 patients had uncemented megaprostheses after a resection of the lower limbs for bone tumors. Antithromboembolic prophylaxis was always administered with LMWH from the immediate postoperative time until the time of complete weightbearing. Phlebographies and vascular ecodoppler were not performed postoperatively on a regular basis. Patients were followed in the clinic with imaging studies for several years (lower limb CT, MRI, CT of the chest for malignant tumors). The diagnosis of symptomatic venous thromboembolism (VTE) was established or excluded on clinical evidence and MRI study. Results: Among the 986 cases treated, only 11 patients (1.1%) showed a major thromboembolic event confirmed clinically and through imaging. One of these patients died with pulmonary embolism a few days after surgery. Two cases of thromboembolism occurred in patients with a vascular bypass. Conclusions: Despite general oncologic and orthopedic factors favoring VTE, the clinical occurrence of this event was extremely low in this series, probably due to a consistent and careful prophylaxis, prolonged until the time of complete weight-bearing