OTA 1997 Posters - Scientific Basis for Fracture Care

Infection Rate of Coralline Hydroxyapatite in Tibial Plateau, Tibial Pilon and Calcaneal Fractures: A Prospective Study

Alexandra K. Schmitt, MD, Stuart M. Gold, MD, Daniel M. Zinar, MD

Torrance, California, USA

Introduction: Bone grafts are an integral part of orthopaedics with over 200,000 bone grafts performed annually in the United States. Although harvesting of autologous bone graft is assumed to have low morbidity, several complications may ensue, including donor site infection, nerve damage and pain. Less common yet serious complications include fractures and hernias. In an effort to reduce donor site morbidity, allograft or synthetic bone graft eliminates all donor site morbidity and does not pose risk of disease transmission. A bone graft substitute known as coralline hydroxyapatite was introduced in early 1970's. After initial histologic, biomechanical and animal studies proved promising, clinical testing began in 1982. The obvious advantages of this xenograft include elimination of donor site pain, infection and stress-riser effects. The potential complications associated with implantation of foreign material are infection, host rejection and implant failure.

Methods: A prospective study was therefore initiated in November of 1993 at Harbor-UCLA Medical Center in order to examine the rate of complications (infection, union, collapse) encountered with the use of coralline hydroxyapatite in tibial plateau, tibial pilon and intraarticular ulnar calcaneal fractures. Ninety-three patients were treated with this bone graft substitute over a 39 month period. Minimal follow-up was 3 months; average follow-up was 11.3 months.

Results: The overall superficial infection rate was 4.2%, the deep infection rate was 3.1%. One patient with a tibial plateau fracture had greater than 5mm collapse at final follow-up. There were no nonunions.

Conclusions: Coralline implants have been shown to be biomechanically and structurally desirable as bone graft substitutes. They are biocompatible as evidenced by lack of reactive cells. Their microstructure closely resembles that of bone and therefore allows total incorporation by osseous ingrowth. In our experience, coralline hydroxyapatite is a safe and effective alternative to autogenous bone grafting in acute periarticular tibial and calcaneal fractures and completely eliminates all donor site morbidity.