TENDINITIS IN HORSES

Inflammation of a tendon can be acute or chronic, with varying degrees of tendon fibril disruption. Tendinitis is most common in horses used at fast work, particularly racehorses. The problem is seen in the flexor tendons and is more common in the forelimb than in the hindlimb. 

Etiology

• Fast exercise  overextension
• Poor conditioning,
• Fatigue,
• Poor racetrack conditions,
• Persistent training when inflammatory problems in the tendon already exist.
• Improper shoeing may also predispose to tendinitis.
• Poor conformation
• Poor training

Clinical Findings and Diagnosis

acute stage, the horse is severely lame and the involved structures are hot, painful, and swollen.

chronic cases, there is fibrosis with thickening and adhesions in the peritendinous area. 
The horse with chronic tendinitis may go sound while walking or trotting, but lameness may recur under hard work.

Treatment

• Tendinitis is best treated in the early, acute stage.
• The horse should be stall-rested, and the swelling and inflammation treated aggressively with cold packs and systemic anti-inflammatory agents.
• Some degree of support or immobilization should be used, depending on the amount of damage to the tendon.
• Intratendinous corticosteroid injections are contraindicated. When a distinct hypoechoic or anechoic core lesion is present on ultrasound examination, tendon splitting has been recommended.
• More recently, cases have been treated with shock wave therapy, intralesional injection of fat-derived stromal cells or cultured bone marrow-derived mesenchymal stem cells, or autologous conditioned plasma.
• The horse should be rehabilitated using a regimen of increasing exercise. Superior check ligament desmotomy has been used as an adjunctive treatment to minimize recurrence of the problem when the horse is returned to training.
• Annular ligament desmotomy is also used when tendinitis involves the area of the digital tendon sheath.

 PREVENTIONS

• Checking the Legs: especially after hard work, it is important to feel each leg for swelling and heat, and to palpate it for pain.
• Correct Trimming and Shoeing: a good farrier will trim the horse's feet correctly, preserving the pastern-hoof angle, and will properly support the horse’s heels.
• Bandaging: using properly applied exercise bandages can help prevent the overextension of the fetlock.
• Correct Conditioning: with a base of long, slow distance work, and a fitness schedule that is not increased too rapidly.
• Suspending Training: if any sign of heat, swelling, or pain is detected

Reference

http://www.merckvetmanual.com/mvm/musculoskeletal_system/lameness_in_horses/tendinitis_in_horses.html