Promoting Bone Formation and Healing in Segmental Defects Through Ectopic Induced Membrane.

We aimed to determine whether addition of an in vivo ectopic induced membrane (EM) to the Masquelet Technique enhanced angiogenesis and bone formation in a segmental defect. After generating and stabilizing a diaphyseal femur defect, 10 rats received a polymethylmethacrylate (PMMA) spacer within the defect (control); 10 received another PMMA spacer implanted subcutaneously (EM). We removed the spacers and added autograft; the excised EM was added to their autograft (EM group). Post-mortem x-rays assessed bone formation and bridging. Osteogenesis in the proximal defect was significantly more uniform (p < 0.01), and there was greater amount of bone remodeling distally in the EM group (p < 0.05). There was no difference in bone formation (p = 0.19) but greater degrees of bridging in the EM group (2.20 vs. 1.20, p = 0.09). The EM resulted in more homogeneous proximal osteogenesis and increased bone remodeling distally. These findings could lead to more consistent and predictable bone healing. (Journal of Surgical Orthopaedic Advances 31(3):161-165, 2022).