Assessment of anterior spine fusion with the use of polyethylene cylindrical tubes in an animal model

Ten dogs of the same species underwent lumbar 5–6 discectomy and adjacent partial corpectomy filled with polyethylene cylindrical tube filled with autologous bone and stabilized with plate and screws. At the end of 5 months follow-up, the dogs were sacrificed and L5-L6 vertebrae were excised en bloc and CT scans were taken. All specimens underwent routine histological examination with hematoxylin and eosin (H&E) and viewed qualitatively with light microscopy. The plain X-rays and CT scans clearly showed the fusion in all dogs. Histological examination disclosed many viable cells and normal lamella of trabecular bone formation in the bone inside and outside of both ends of the polyethylene tube. Remodeling of the bone inside the tube was apparent. Combined reconstruction using anterior polyethylene tube with anterior instrumentation after partial corpectomy and discectomy makes it possible to achieve biological fusion of the bone inside the polyethylene tube with adjacent vertebral bodies. However, further animal studies from biomechanical standpoint will be helpful for their future human usage.