A cruciate ligament injury is one of the most common causes of hind leg lameness in dogs. The cruciate ligament sits inside the knee joint and helps stabilise the joint during movement.

When this ligament becomes damaged or ruptures, the knee becomes unstable and painful.

Dogs with a cruciate injury may show:

 • sudden limping after running or playing
• ongoing limping that improves and then returns
• difficulty rising from a resting position
• reluctance to jump, climb stairs, or exercise
• stiffness after activity
• sitting with one leg extended outward rather than tucked underneath
• swelling around the knee joint

Some dogs develop cruciate injuries gradually as the ligament weakens over time. Others may injure the ligament suddenly during activity.

Because the knee joint becomes unstable after a cruciate injury, early assessment and treatment are important to help protect the joint from further damage.

→Diagnosis of Cruciate Injuries

If your dog has persistent hind leg lameness, a veterinary examination can help determine whether a cruciate injury may be present.