Lameness due to Joint Problems
Any athlete can suffer from joint pain or injury and the horse is no exception. When horses perform sudden stops and sharp turns, there is significant force placed on the joints of the rear limbs. Horses that gallop greatly extend their lower limbs and place significant force on their fetlocks. While joints may be affected differently depending on the equine discipline, lameness caused by joint pain can be a common problem in the performance horse.
Anatomically, joints act as hinges and shock absorbers which allow for smooth motion between long bones. All joint surfaces are lined with cartilage and the joint cavity is filled with joint (synovial) fluid. Cartilage absorbs and cushions the dynamic forces of movement, and synovial fluid nourishes the cartilage and lubricates the joint. Healthy joints have a smooth joint surface with balanced production and elimination of synovial fluid from the joint capsule.
Long-term joint inflammation or an sudden, severe injury can lead to permanent damage to the joint surface and the horse may develop arthritis. Joint enlargement can be one of the first signs of an unhealthy joint, although not all horses with joint enlargement have a significant problem. Excessive fluid in a joint can occur due to an injury, presence of a developmental bone chip (Osteochrondritis dissecans or OCD), or arthritis (inflammation of the joint leading to degenerative joint disease). Often, the joint will remain somewhat enlarged even after the cause has been corrected.
When performing a lameness examination, your veterinarian will carefully evaluate your horse's joints. Diagnosis of joint lameness involves examination of each limb and observation of the horse in motion, usually at a walk and trot. Monitoring the horse's gait following flexion of the limb (flexion test) can help to determine which joint is the source of pain. Your veterinarian may also “block” the joint by aseptically injecting a local anesthetic solution into the joint, to assess if the horse's lameness improves. Finally, your veterinarian may use additional diagnostic tests such as radiography, ultrasonographic evaluation, Magnetic Resonance Imaging (MRI) and nuclear scintigraphy (bone scan) to determine the extent of damage and develop appropriate treatment options.
Depending on the diagnosis, treatment options may include stall rest, anti-inflammatory medications and injecting the joint with medications such as corticosteroids and hyaluronic acid. For more severe problems such as bone chips, fractures or chronic arthritis, surgery may be recommended. Through careful evaluation and use of diagnostic techniques, your veterinarian will recommend treatment that will help your horse with lameness due to joint problems.
Lameness from joint pain will cause significant performance problems regardless the horse's age, breed or use. By careful evaluation and use of diagnostic techniques and procedures, your veterinarian can recommend a proper treatment that will help your horse safely perform to the best of his ability. If you have questions about a lameness issue or any concern regarding the health and well-being of your horse, do not hesitate to call your veterinarian who will be glad to assist you.