Short Ulna Syndrome
Short ulna syndrome is a term used to describe the condition whereby one or both of the ulnar physes (these are sometimes called growth plates and are areas of cartilage from where the bone grows) close prematurely, often secondary to trauma. In large breed dogs, the condition can also be caused by abnormal cartilage turnover. In addition to this, overnutrition (excess calcium, calories or an overweight puppy) is speculated to play a role in the development of this disease, particularly in breeds thought to be genetically predisposed e.g Great Danes, Irish Wolfhounds and the Bassett Hound.
The treatment, should treatment be required, is surgery. If diagnosed in a young puppy, where there is still substantial growth potential, cutting the ulna bone relieves the constraining effect on the radius allowing continued limb growth and releasing pressure upon the joint surfaces.
In more mature dogs, a corrective osteotomy and stabilisation (bone cut and fixation with plates and screws or an external frame) can be used to realign and stabilise the joint and limb for more normal configuration. If the condition is diagnosed later, joint instability and degenerative joint changes may be too far progressed and reconstructive surgery can be less effective.
In the Hungarian Wirehaired Vizsla the Association is aware of only 3 SUS cases. The puppies are siblings.