Fresh frozen allografts were obtained from our university bone bank, which harvests and stores the allografts according to the standards of tissue banking protocols for allograft processing and preparation. To minimize the joint incongruency as much as possible, we tried to match the size of the allograft with the host femur using comparative patient and donor imaging analysis. After 2015, the majority of reconstructions were performed using a rAPC technique. For this purpose, the femoral component of an unconstrained TKA prosthesis (Innex® Gender Solutions™ Primary Knee System, Zimmer) was cemented in the selected osteoarticular allograft and then fixed to the host femur with a lateral bridging plate and screw system. Resurfacing technique allowed remodeling of oversized allograft to match the size of the host tibial condyle. The medullary canal of all allografts was augmented with bone cement. The ligament and capsule of the allograft were sutured to its counterpart in the proximal tibia as much as possible. The knee stability was checked at the end of the procedure. To prevent joint subluxation, in patients with an unstable knee, we fixed the joint with two Steinmann pins at 15º flexion for six weeks . During the follow-up, the limb-length discrepancy was assessed clinically and radiographically. If the discrepancy was predicated on exceeding 3 cm, epiphysiodesis of the contralateral was implemented.  the knee was immobilized for six postoperative weeks in a long-leg cast. Isometric quadriceps exercises and passive mobilization were started afterward. Patients were kept on partial weight-bearing until the radiologic union of the allograft. ‎ Follow-up visits were performed every three months for the first two years, every six months for the next three years, and yearly thereafter.

Reference;

Jamshidi, Khodamorad, Abolfazl Bagherifard, and Alireza Mirzaei. "A comparison of osteoarticular allografts and allograft-prosthesis composites for reconstruction of the distal femur after resection of a bone tumour in childhood: a retrospective study." The Bone & Joint Journal 104.10 (2022): 1174-1179.