Degenerative changes after meniscectomy and meniscal regeneration.

In an experimental study on rabbit knees, regeneration of the medial meniscus occurred following 9 out of 10 meniscectomies, compared with only 1 out of 10 lateral menisci. Degenerative changes in the articular cartilage were seen in 8 of 9 knees where the lateral cartilage failed to regenerate, but in only 2 of 9 with a regenerated medial cartilage. The rate of regeneration is lower after lateral meniscectomy and this may partially explain the occurrence of more severe degenerative changes after this operation.