Sprain like sprained fetlock
The sprain is characterized by the achievement of a ligament or two. This condition is often caused by trauma or due to over-exertion of the horse kind breakdown. This is a common condition in horses. It is characterized by joint swelling in connection with an instability. There is also a warmth and a greater or lesser lameness depending on the intensity of the ligament reached. Diagnosis is clinical and ultrasound, see for MRI according to the location of the affected ligament.
In the ultimate case of severe sprain, you can go to a ligament tear and at that time the shutdown period is much longer and the recovery of the horse is not certain.