Meniscal allografts - Where do we stand?

Meniscal transplantation has been recommended for selected meniscus-deficie nt patients in an effort to forestall progressive joint degeneration. Menis cal allograft transplantation may be considered for patients with symptoms (pain and swelling) due to meniscal deficiency in an effort to prevent prog ressive articular cartilage degeneration. Medial meniscal transplantation m ay also be considered during concomitant anterior cruciate ligament reconst ruction, since absence of the medial meniscus results in increased forces i n the anterior cruciate ligament graft. Contraindications for meniscal tran splantation include advanced articular cartilage degeneration (especially o n the flexion weightbearing zone of the condyle), axial malalignment, and f lattening of the femoral condyle. Patient evaluation should include standin g, long-leg radiographs for assessment of the mechanical axis and magnetic resonance imaging with appropriate pulse sequences for evaluation of hyalin e cartilage thickness. Fresh-frozen and cryopreserved allografts are curren tly the most commonly used transplantation materials. Appropriate graft siz ing is critical; most tissue banks size the meniscus based on radiographic tibial plateau measurements. Early results of meniscal transplantation indi cate predictable improvements in pain, swelling, and knee function; however , no long-term results are available. Poor results have been reported in pa tients with advanced cartilage degeneration. Objective evaluations often de monstrate some degree of degeneration of the posterior horn of the transpla nt. Earlier transplantation should be considered for patients with known me niscal deficiency.