Mid- to long-term effects of two different biological reconstruction techniques for the treatment of humerus osteosarcoma involving caput humeri.

Background: The proximal humerus is one of the most common sites of primary or metastatic malignant tumors. Reconstruction of the shoulder after tumor resection is controversial and challenging. When intra-articular resection is performed, biological reconstruction (osteoarticular allograft and autologous bone implantation) may be the first choice rather than prosthetic reconstruction.

Objective: To observe the mid- to long-term effects of oncologic, reconstructive, and functional outcomes of two different biological reconstruction methods for resection of humerus osteosarcoma involving caput humeri.

Methods: This was a retrospective study of 13 consecutive patients who underwent humeral reconstruction of osteosarcoma including caput humeri using osteoarticular allograft (n = 7) and tumor bone inactivated and reimplantation (TBIR, n = 6) in our clinic between 2007 and 2017. Patients' general information, resection and reconstruction techniques, oncological and functional outcomes, and complications were collected and evaluated. Different complications of implantations were compared and analyzed for the different biological methods.

Results: The study included ten males and three females with an average age of 19.15 years. The operation time was about 3.65 h with an average blood loss of 631 ml. The resection tumor bones were 13-45 cm (23.54 cm on average). The mean follow-up period was 5.27 years. The shoulder movement was 10-70° (average, 44.00°) in abduction, 0-30° (average, 14.17°) in flexion, and 0-20° (average, 11.90°) in extention at the last follow-up. The complications included fracture in four TBIR patients and two allograft patients with an average of 2.67 years postoperation. Fracture rate was higher and appeared time was earlier in TBIR patients than in allograft patients (p = 0.04); caput humeri absorption occurred in all seven allograft patients and three TBIR patients at an average of 3.10 years after surgery; severe graft bone resorption appeared in five TBIR patients and two allograft patients at an average of 2.57 years of follow-up.

Conclusions: Humerus biological reconstruction involving caput humeri was associated with a high complication rate and acceptable limb function in the mid to long term. New combined biological methods should be explored and adopted in the future.