Effects of movement and weightbearing on the glycosaminoglycan content of sheep articular cartilage

Abstract

Immobilised non-weightbearing joints show significant loss of proteoglycan. It is unclear whether this is due to a lack of compression, a lack of movement, or both. Evidence suggests that movement alone is insufficient to maintain proteoglycan levels. To investigate this problem, 20 sheep were divided into four groups and the right forelegs subjected to (1) normal weightbearing and movement, (2) movement without weightbearing, (3) weightbearing without movement and (4) non-weightbearing without movement. After one month, full thickness core samples of cartilage taken from the radio-carpal joints of both forelegs were analysed for glycosaminoglycan (GAG) content. Immobilised non-weightbearing joints showed a significant loss of GAG compared with the other groups. More importantly, movement alone without weightbearing was sufficient to maintain GAG content, as was weightbearing without movement.