Cranial Cruciate Ligament (CCL) Injury
The canine equivalent of an ACL tear — a common cause of sudden hindlimb lameness.
What is Cranial Cruciate Ligament (CCL) Injury?
The cranial cruciate ligament stabilises the stifle (knee). In dogs, CCL rupture is usually the end result of chronic degeneration rather than acute trauma. Once one CCL fails, the other has a roughly 50% chance of failing within 1–2 years.
Common signs and symptoms
Signs vary between dogs and can be subtle at first. Watch for the following, especially if several appear together or persist for more than a few days:
- Sudden hindlimb lameness, often after a run or slip
- Toe-touching or holding the leg up when standing
- Sitting with the affected leg out to the side ('sit test')
- Swelling on the inner side of the knee (medial buttress)
- Chronic lameness that waxes and wanes
Risk factors
Certain dogs are more predisposed. Understanding risk helps you screen earlier and act sooner.
- Overweight body condition
- Labrador, Rottweiler, Bulldog, Newfoundland, Boxer
- Middle-aged dogs (5–7)
- Poor conditioning combined with weekend-warrior activity
When to see a vet
Use this as general triage guidance, not a substitute for veterinary advice.
- Book a routine appointment if: any hindlimb lameness lasting more than a few days.
- Seek urgent care if: complete inability to bear weight, or a knee that looks obviously swollen or unstable.
Diagnosis and management
Diagnosis is a physical exam ('cranial drawer', 'tibial thrust') often combined with sedated exam and X-rays. Surgical stabilisation (TPLO, TTA, or lateral suture) generally gives better outcomes than non-surgical management, especially in dogs over 15 kg. Rehab is critical to a good result.