Viable Meniscal Transplantation

Abstract

It is postulated that restoring the normal congruency between femur and tibia with normal menisci could be a solution to many mechanical knee problems.

Good functional results have been achieved with the transplantation of menisci in compartmental meniscal degeneration. However, this type of chondroprotection can only be evaluated after 10 to 20 years of follow-up.

Satisfactory incorporation of meniscal transplants has been obtained with fresh allografts, but availability remains a problem with this method of meniscal substitution.

Incorporation and ingrowth of fibroblasts have been shown in freeze-dried and deep-frozen meniscal allografts. In a small number of transplants shrinking has been observed on repeat arthroscopy.

Viable meniscal allograft implantation has been initiated in a series of 25 patients. The value of this method has been studied. With the use of a semisynthetic medium the semilunar cartilages can be kept viable without apparent loss of fibrochondroblast cell activity. During this incubation period the appropriate recipient can be selected and prepared. There is sufficient time to conduct laboratory screening and to evaluate the culture results and disease transmission factors. In this way, live transplant hazards can be avoided which results in a higher success rate.

It should be kept in mind that the knee is a weightbearing joint. The patient himself is responsible for mechanical loading, and medical control of these conditions is not always possible.

The intensity of loading thus remains an aspect that cannot always be determined scientifically and must be considered in pathology.

In view of the promising results obtained with tendon allografts and with meniscal allografts in sheep [5], meniscus transplantation in humans has become an attractive treatment option, while the outcome of synthetic meniscus replacement has been rather disappointing. Meniscal transplantation involves the necessity to store and preserve meniscal material.