Scoliosis after extended hemipelvectomy

Study Design: Retrospective review plus 2 representative case reports. Objective: To evaluate the prevalence of scoliosis after extended hemipelvectomy (EH) and illustrate the problem's severity. Summary Of Background Data: No published series has analyzed this problem. Data are needed to decide the potential need for and timing of spine fusion in these patients. Methods: We treated 14 patients with EH over 10 years. Mean age was 47 years. Diagnoses included osteosarcoma (6); chondrosarcoma (4); metastatic cancer (2); and MFH and undifferentiated sarcoma (1 each). Operating time ranged from 7 to 15 hours, and mean estimated blood loss was 8 L. Patients were observed for scoliosis, functional results, and for oncological outcome (survival, disease progression). Two patients who became scoliotic after EH illustrate the problem: a 31-year-old man underwent EH for pelvic osteosarcoma and progressively developed a painful 44° scoliotic curve; and a 27-year-old woman who developed a 60° painful scoliotic curve and radiculopathy years after EH including L5-S1 disc disruption. Results: Of 12 patients, 8 died within 7 months of EH. Only 2 of 12 patients are long-term survivors free of disease (3 and 6 years after surgery), and 2 are alive with disease more than 1 year after surgery. In patients >1 year survival, 3 of 4 patients had curves greater than 20°. Of 10 evaluable patients, 2 developed a curve greater than 30° that warranted fusion. Four others had curves between 20° and 30°. Of these 6, 5 developed a sharp-angled lumbar curve with the concavity away from the operated side. Risk factors for symptomatic scoliosis after EH include disc disruption, paraspinal muscle/ligament resection, or facetectomies in ambulatory patients with a lengthy survival. Conclusion: Primary spinal fixation should be avoided because of the high morbidity and early mortality of EH. Selected high-risk patients can be stabilized later if they develop painful instability.