Osteoarticular extracorporeally irradiated autograft following resection for primary malignant bone tumors - An assessment of functional outcome in 32 patients.

Background: Extracorporeally irradiated autografts at an osteoarticular location following resection of malignant bone tumors have unique considerations. While oncological outcomes remain similar to other modes of treatment, joint function is directly affected due to the articular location of the autograft. There is limited literature focusing specifically on long-term functional outcomes in such reconstructions. We report on the functional outcomes of extracorporeally irradiated osteoarticular autografts. Methods: 32 patients who underwent extracorporeally irradiated osteoarticular autografts following resection of malignant bone tumors between the years 2010-2022 were assessed for functional, radiological outcomes and complications. The functional outcome was assessed by the Revised Musculoskeletal Tumor Society Rating Scale and radiographic changes were documented by the International Society of Limb Salvage graft evaluation criteria. Complications following surgery were noted. Results: The median Revised Musculoskeletal Tumor Society (MSTS) score for the lower limb was 18 (Range 13-30) All three upper limb patients scored 21. The mean ISOLS radiographic score was 53.5 % (Range 46.4 %-74 %). The proximal humerus had the lowest radiological score. The most common complication was the collapse of the articulating condyles (94 %) which manifested clinically as joint instability. The infection rate was 9.3 % and major reoperation rates were 34.4 %. Conclusion: While oncological outcomes of osteoarticular extracorporeally irradiated autograft following resection for primary malignant bone tumors are comparable with other methods, the complication rate particularly joint instability and graft collapse are significant. The high rate of non-oncological complications may limit the long-term viability of such grafts.