Clinical and morphophisiological aspects of the rat knee articulation after immobilization and remobilization / Aspectos clínicos e morfofisiológicos da articulação fêmorotibio-patelar de ratos após imobilização prolongada e remobilização

AUTOR(ES)
DATA DE PUBLICAÇÃO

2005

RESUMO

The aim of this study was to evaluate the clinical and morphophisiological aspects of the rat knee articulation after immobilization and remobilization with free activity and swimming. Thirty four adult male rats (Wistar) were randomly allocated into one of four groups: without immobilization, (G1, n = 4), with immobilization (G2, n = 10), immobilization and remobilization with free activity (G3, n = 10), and immobilization and remobilization with free activity and swimming (G4, n = 10). Animals had the right knee joint immobilized for 45 days. Animals from G2 were killed after this immobilization period and so were those from G1. After the immobilization period animals from G3 were allowed to move freely in their cages and those from G4 add to that were submitted to a swimming program for 5 weeks and were than all killed. During the remobilization period animals from G3 and G4 had their march clinically evaluated. After being killed the articular amplitude of the right knee was assessed in all animals and histological slices from the articular capsule, cartilage and subchondral bone were obtained. The results showed that animals from G4 exhibited a better march evolution on the first five days period as compared to those from G3. After such period march evolution were similar in both G3 and G4. Animals from G2 displayed rigid joint while in those from G3 and G4 the articular movement was close to normal. The histological analysis pointed out that immobilization led to increase in articular capsule thickness evidenced by the presence of fibrous connective tissue replacing adipose tissue in G2, but proportionally less in G3 and G4. By the analysis of the articular cartilage and subchondral bone it was observed that immobilization determined loss of proteoglycans from the cartilaginous matrix, increase in the number of regularly arranged condrocytes, increase in calcified cartilage thickness, irregularity in the articular surface, proliferation of connective tissue in the intraarticular space and increase in subchondral bone thickness. A animals from G3 displayed a greater number of alterations in both articular cartilage and subchondral bone, as compared to those from G4. It was concluded that: immobilization degenerated synovial cells indicating decreased synovial fluid production and reduced nutritional supplying to the cartilage; and both free cage activity and its association with swimming influenced positively the return of the capsule morphologic conditions to those before immobilization.

ASSUNTO(S)

movimento rats cartilagem articular knees clinica e cirurgia animal articulation joelhos movement ratos articulações articular cartilage

Documentos Relacionados