Fate of Vascularized Interposed Joint Capsule at Femorotibial Space in Rabbits

Kim, Jung Man; Kong, Joon Taek; Han, Chang Whan; Choi, Jin Wha

Abstract

The present study was designed to investigate the interposed joint capsule at the femorotibial space following meniscectomy which could contribute to the regeneration of meniscus. Thirty two rabbits were used for this study. The anterior half of the medial meniscus was resected and the joint capsule was cut transversely 4mm above the joint line. It was reflected and interposed at the meniscectomized site. Gross findings at 2, 6, 8, and 12 weeks were recorded, respectively. Hematoxylin-Eosin(H-E) and safranin-O staining were done for histological and histochemical study, respectively. The results were as follows : 1 . With tile passage of time, interposed joint capsules looked like normal meniscus in shape, and the surface was glistening. 2. At 12 weeks, the width and thickness of interposed tissue were gradually decreased until it became normal size (P>0.05). 3. Histologically(H-E stain), the interposed tissue consisted of dense connective tissue with fibrocyte at 2 weeks. The interposed tissue changed to wedge shape and consisted of dense connective tissue with fibrocyte and prolifelated synovial cells at 6 weeks. Immature chondrocytes appeared at the lower portion and fat cells appeared at the upper portion of the tissue at 8 weeks. The fat cells disappeared and more mature chondrocyte were found in the central portion of interposed tissue at 12 weeks after operation. 4. Histochemical study(safranin-O stain) showed the interstitial tissue was not stained at 2 and 6 weeks, but glycosaminoglycan synthetic activity increased in the newly formed chondrocytes at postoperative 8 weeks and 12 weeks. From these results, the interposed capsule at the femorotibial space could be a substitute material for postmeniscectomy patients.