Effect of ultrasound on glycosaminoglycan metabolism in the rabbit knee

The effect of ultrasound therapy on glycosaminoglycan metabolism in articular cartilages, menisci and capsular tissues of rabbit knee was studied using both autoradiography and biochemical methods. Glycosaminoglycans were examined by determining the uronic acid, glucosamine and galactosamine contents and the specific radioactivity of galactosamine of the purified substances. A total of 31 rabbits were used, 13 of which received ultrasound treatment, power 1 W/cm2, to the right knee 5 minutes a day for five days. The specific radioactivity in separated glycosaminoglycans of the medial collateral ligament of the treated knee was 69% higher than that of the controls and 36% higher than that of the contralateral ligament. The same effect was seen in autoradiography. Glycosaminoglycan concentrations of articular cartilage, menisci and collateral ligament were unaltered. The result may indicate that the main effect of ultrasound therapy is on the capsular tissues of a healthy joint.