GROSS AND HISTOMORPHOLOGICAL EFFECTS OF THERAPEUTIC ULTRASOUND (1-WATT CM2) IN EXPERIMENTAL ACUTE TRAUMATIC ARTHRITIS IN DONKEYS/

Acute aseptic arthritis was induced in 8 healthy donkeys aged 3-4 pear s and weighing 80-100 kg. The animals were divided into two groups (A and B) of four animals each, Group A served as a control where as in g roup B pulsed ultrasound therapy was applied for 10 minutes @ 1 Watt/C m-2 from day 2 to 8 after induction of arthritis, The gross changes in the joint capsule, synovial membrane and articular cartilage were qui te mild in ultrasound treated animals as compared to controls, Microsc opically, the joint capsule showed complete sloughing of the intimal l ayer and the subintimal layer showed severe inflammatory reaction or e ven complete necrosis of the fibrous capsule and synovial membrane in untreated animals, The joint capsule of ultrasound treated animals sho wed an advanced healing stage of the synovial membrane though still so me inflammatory reaction was present in the subintimal layer, Synovial membrane of untreated animals showed less of acid mucopolysaccharides material and more of neutral mucopolysaccharides as compared to treat ed animals, Calcium deposition was not detectable in the joint capsule of the treatment group. Degeneration of articular cartilage was obser ved microscopically in control animals as marked by fibrillation and d esquamation of perichondrial tissue with necrosis of chondrocytes in d ifferent layers or even complete sloughing of the articular cartilage. Articular cartilage of ultrasound treated animals had mild changes in the superficial layer (devoid of chondrocytes) and the rest of the ca rtilage layers were histologically normal.