STABILIZATION OF OSTEOCHONDRAL FRACTURES - AN EXPERIMENTAL-STUDY COMPARING POLYGLYCOLLIC ACID DEGRADABLE PIN WITH K-WIRE STABILIZATION IN RABBITS

Conventional metal implants may be unsuitable for the stabilization of osteochondral fractures as they may interfere with joint function and eventually require implant removal. We therefore compared the use of biodegradable implants with conventional metal ones in an animal exper imental study conducted in skeletally mature rabbits. Biodegradable po lyglycollic acid pins (PGA) 1.5 mm in diameter were used to stabilize an osteochondral fragment surgically created in the distal femur of ra bbits. In another group of 36 animals, conventional metal K-wire of th e same diameter was used for stabilization. The animals were killed at intervals of 3 to 24 weeks. Satisfactory union of the fragments was n oted in 92% of the PGA implants as compared with 50% with the metal im plants group. No implant migration was seen in the PGA group, while mi gration was noted in all animals with the metal implants, Histological studies showed that in 80% of the cases fixed with PGA implants, the fragment was viable. In the metal group 33% of the fragments underwent fragmentation and necrosis.