Articular cartilage degeneration after frozen meniscus and Achilles tendon allograft transplantation: experimental study in sheep

PURPOSE
The purpose of this study was to analyze cartilage degeneration in knees after total medial meniscectomy, transplantation of fresh-frozen meniscus allograft, and Achilles tendon allograft.

TYPE OF STUDY
Experimental study.

METHODS
We have studied the articular cartilage in the medial compartment of the left knees in 32 sheep aged 5 to 6 months, with 8 animals in each group. The study was performed after meniscectomy (group I), transplantation of fresh-frozen meniscus allograft (group II), use of fresh-frozen Achilles tendon allograft (group III), and in a control group (group IV).

For the histologic study, all samples were stained with Masson's trichrome and Safranine-O. Mankin's score was applied to grade the histologic damage to the articular cartilage.

RESULTS
The group with the greatest number of degenerative changes was group III, followed by groups I and II. The percentage of thickness of cartilage detected by Safranine-O stain was found to be significantly different in both tibia and femur between the control group and the other 3 groups, but not among groups I, II, and III.

The immunoreactivity of the articular surfaces in tibia and femur showed notable differences in all the groups. Collagen X was present in the degenerative hypertrophic chondrocytes in the damaged articular surfaces.

CONCLUSIONS
Meniscal replacement with meniscal and Achilles tendon allografts provides partial protection against articular damage after a meniscectomy.

CITA DEL ARTÍCULO  Arthroscopy. 2003 Oct;19(8):833-41