Abstract The equine metacarpophalangeal joint (MPJ) is of significant clinical importance but there is limited data regarding the effects of immobilization and remobilization on potentially diagnostic biochemical parameters of the fluid within the joint. Five horses underwent clinical examination for lameness and joint flexure to document limb health before acceptance to the study. One of the thoracic limbs was randomly assigned to half-limb cast immobilization for a period of 5 weeks. After cast removal, the horses were subjected to increasing amounts of exercise, beginning with hand-walking and ending with trot. Synovial fluid of the immobilized joints was taken before casting and after cast removal at days 0, 7, and 14. Glucose, total protein, quality of mucin clot, alkaline phosphotase, aspartate aminotransferase (AST), lactate dehydrogenase (LDH), joint diameter, and cell count were measured. Joint diameter was significantly decreased when the cast was removed ( <0.05). Glucose, AST, and LDH were increased significantly only at day 7 after removing the cast ( <0.05), and thereafter no significant changes were observed. Immobilization and remobilization of the normal equineMPJ have no significant effects on the biochemical and cytological properties of the synovial fluid in this joint.

Keywords