Page 582 - The Veterinary Care of the Horse

stabilize the joint. Pain arises when these ligaments are strained and subsequent joint

instability may lead to degenerative, osteoarthritic changes. However, our understanding of
VetBooks.ir sacroiliac disease is incomplete because the joint lies under a large muscle mass and is not
accessible to many of our diagnostic techniques and imaging methods.

Causes

Acute sacroiliac disease may be caused by:

• an acute traumatic injury, e.g. slipping or falling during work or flipping over backwards
• any injury that causes pelvic rotation can strain the sacroiliac ligaments and joint

• complete fractures of the ilial wing (see page 377) can cause instability of the sacroiliac

joint.

Chronic sacroiliac disease:

• may be the result of long-term overuse of the horse leading to sacroiliac joint
osteoarthritis rather than a single traumatic incident.

• can develop if an acute injury is not rested sufficiently

• may develop secondary to a lower hind limb lameness that changes the horse’s gait and
puts strain on the sacroiliac ligaments.

Clinical signs

These are variable and depend on whether the horse has an acute injury or chronic disease. If

the injury is acute, the horse is likely to show the following.
• Significant hind limb lameness on the affected side.

• Painful spasm of the overlying gluteal muscles and abnormal tension in the hamstring

muscles.
• Pain when firm pressure is applied to the tubera sacrale and surrounding soft tissues.

• If the sacroiliac ligaments rupture and the joint surfaces are partially or completely torn

apart (known as subluxation and luxation respectively), there may be an upward
displacement of the tuber sacrale on the side of the injury which was not present before
the injury occurred. Bilateral disruption and displacement can occur. These injuries are

uncommon.
• With a complete ileal wing fracture, the tuber sacrale is often displaced downwards on

the affected side (see Figure 12.24)