Rex the fun loving kelpie was running in the park chasing his ball when he suddenly couldn’t put any weight on his left hind leg.

A veterinary examination revealed a suspected cranial cruciate ligament rupture (CrCl) – one of the most common orthopaedic conditions seen in the dog.

CrCl rupture can be an acute (sudden) or chronic degenerative injury and results in partial or complete instability of the knee joint.  It is similar to anterior cruciate ligament problems in humans, often seen in footy players or skiers.

There are two cruciate ligaments in the knee and they cross each other as they pass between the femur and the tibia.  If the knee is subjected to twisting (such as when chasing a ball or jumping off a large height) the ligament can tear and even rupture.

Rupture is often a gradual process, resulting from chronic inflammation of the knee joint.  Age-related changes, repetitive activities, poor conformation, obesity and immune-mediated diseases are some of the more common causes. More active and large breeds of dogs may be predisposed to cruciate ligament rupture.

Cruciate ligament rupture also predisposes other structures within the knee to injury resulting in the progression of the osteoarthritis and lameness. Bilateral disease, where both knee joints are affected, is common.

To definitively diagnose and accurately assess the extent of the problem, Rex’s injury needed further investigation.  Please click here to read the rest of Rex’s story in our newsletter.