Comparison of survival, function and complication between intercalary frozen autograft versus massive allograft reconstruction after malignant bone tumors resection

Purpose This study aims to compare the clinical outcomes of intercalary frozen autograft and allograft reconstruction for primary malignant bone tumors. Methods A retrospective study was conducted on 144 patients who underwent intercalary biological reconstruction for primary malignant bone tumors at a single institution between January 2012 and July 2023. Seventy-two patients underwent intercalary liquid nitrogen-frozen autograft reconstruction, and 72 patients underwent intercalary allograft reconstruction in this study. A modified International Society of Limb Salvage classification system was used to evaluate the complications. Results The mean follow-up time was 60.2 +/- 32.1 (range, 12-149) months. The mean union time was 9.6 months in the frozen autograft group and 15.9 months in the allograft group (p < 0.001). The 5-year overall survivorship was 86.8% in the frozen autograft group and 73.2% in the allograft group (p = 0.017). The average MSTS-93 score was comparable between the two groups (89.7% by autograft versus 87.6% by allograft, p > 0.05). Of the patients, 48.6% (70/144) had at least one complication. The most common complications were bone nonunion (20.8%, 30/144), followed by structural failure (17.4%, 25/144), tumor progression (10.4%, 15/144), infection (10.4%, 15/144), and soft tissue failures (5.6%, 8/144). Higher rates of bone nonunion (type 4B; p = 0.002) and structural failure (type 3B; p = 0.004) were obtained in the allograft group than in the frozen autograft group. Conclusions The intercalary frozen autografts had shorter union time and lower complication rates than allograft reconstruction. Therefore, we recommend that frozen autograft reconstruction be considered when the tumor bone has not suffered severe osteolytic injury or pathological fracture.