Experimental meniscal allografts in the rabbit

Abstract

Meniscal injury belongs to most common consequences of stifle trauma in humans. Its treatment usually consists of partial meniscectomy; this procedure, however, predisposes the knee to progression of gonarthrosis and thus increases morbidity and subsequently raises drug consumption. Progression of pathologic changes often leads to implantation of total knee prosthesis. With development of arthroscopy, the number of salvage procedures of injured menisci increased. This method also reduces progression of arthrotic changes. However, not every meniscal lesion is reparable and not every reinserted meniscus will heal. That is why the number of performed meniscectomies is still high. The purpose of this study was to verify on experimental model if transplantation of fresh and frozen medial meniscal allografts into the stifle joints after total meniscectomy reduces progression of gonarthrosis. Progression of arthrotic changes in stifle joints after total meniscectomy was evaluated in three groups of 8 rabbits: group 1: rabbits after total meniscectomy without meniscal transplantation (control); group 2: meniscectomy followed by transplantation of fresh meniscal allograft; group 3: transplantation of deep frozen (-80°C) meniscal allograft. The results of surgical procedures were evaluated both clinically and radiographically. The quality of allograph incorporation was evaluated both macroscopically and histologically 4 months after the surgery. Severe osteoarthritis developed in rabbits after total meniscectomy. In both groups after meniscal transplantation, allografts healed with well functional stifles and progression of gonarthrosis was reduced comparing to the group of rabbits after meniscectomy alone. The extent of arthrotic changes was smaller after transplantation of frozen allografts than after transplantation of fresh allografts. Histology of stifles with fresh meniscal transplants showed more pronounced perivascular inflammatory infiltration in site of transplant insertion to the joint capsule than in the frozen allografts. Promising results of this study need to be verified in clinical cases.