Comparison of Bony Healing and Cartilage Degeneration Following Strut Grafting and Trapdoor Procedures in an Ovine Model

Abstract

This experimental study compared bony healing and cartilage degeneration following strut grafting and trapdoor procedures for osteonecrosis of the femoral head in an ovine model. Osteonecrosis and a bony defect were created surgically in 16 hips of 8 Merino sheep, and the index grafting procedures were performed in a second session. Three months after surgery, the hips treated by strut grafting yielded better articular cartilage protection and bony healing compared to the osteonecrosis groups. The trapdoor group yielded better bony healing compared to the rest of the groups, but the grafts and the osteochondral flaps failed to unite with the host bone. These findings indicate elevating the osteochondral flap during the trapdoor procedure injures the cartilage and may cause degeneration.

A Canine Model of Femoral Head Osteonecrosis Induced by an Ethanol Injection Navigated by a Novel Template

“…These methods include cryogenic insult by liquid nitrogen 17-20, ethanol injection 11-14, osteotomy 21-24. Among these methods, cryogenic insult and ethanol injection have been most commonly used; however, there is no consensus on the best model that will mimic human ONFH.…”

“…Whilst this approach has been adopted and replicated 12-14, there are no reports on this application in canines. Both sheep and canines are usually used animals, which are especially suitable for testing procedures.…”