Question of the Day

This is bone spavin, an osteoarthritis/degenerative joint disease of the distal hock joints, usually affecting the distal intertarsal and tarsometatarsal articulations. The number one hock problem (tarsus) in horses.

If the horse is lame due to bone spavin, it tends to drag toe or have « stabbing » gait in the affected hindlimb. Occasionally you may see thickening of the soft tissues over distal hock joints. The problem can be unilateral or bilateral with various degrees of lameness. 

Typical Tx: intra-articular steroids and hyaluronic acid, phenylbutazone as needed, continue with work. Over time distal hock joints are likely to ankylose (fuse) on their own and lameness ends. Additional treatments include shockwave, bisphosphonates, alcohol arthrodesis, cunean tenectomy or neurectomy.

Tarsal hydrarthrosis (bog spavin) is a chronic synovitis of the tarsocrural joint – look for swelling and distention of the joint capsule.

Image courtesy of Nora Grenager, VMD, DACVIM.