Cruciate Ligament Tear/Rupture

Overview:

This condition is the #1 orthopedic injury seen in veterinary hospitals. It is more common in larger breed dogs, but any breed dog and cats can tear their cruciate ligaments. Overweight pets are more at risk.

Causes:

There is usually a traumatic event that causes the tear, but some owners can not determine when their pet would have torn the ligament. Smaller pets that have medial luxating patellas that are not treated also can develop tears in the knee secondary to the condition.

Symptoms:

Pets will exhibit lameness in the limb affected, sometimes not bearing any weight at all. The knee can be swollen or develop a thickening on the inside aspect. Chronic symptoms include atrophy of the thigh muscles. Pets that have torn a ligament in one knee are predisposed to tear the other knee due to excessive weight bearing on that particular knee.

Treatment:

Surgical repair is generally the best option, especially if the patient is greater than 30 pounds or there is also a meniscal injury. However, if there is only a partial tear and the patient is less than 30#, medical management is possible. Strict rest is mandatory for at least 10-14 days and antiinflammatories are used to alleviate discomfort. These pets are at risk of tearing their ligament multiple times and will probably need surgery at some point in the future. Be aware the longer surgery is avoided, the more likely arthritis will develop in the knee. Weight loss is imperative, as heavier animals are more likely to have the surgery not be effective or to tear their ligaments multiple times.