We are not veterinarians, and this is not veterinary advice. Every clinical statement below is attributed to a named veterinary source and linked, so you can check it against the original rather than take our word for it. Where the evidence is genuinely unsettled, we say so instead of picking a side. If your dog is in pain or cannot bear weight, contact a vet today. Last updated 2026-08-19 · How we source our content

If your Labrador has started limping on a back leg, cruciate ligament disease is one of the first things a vet will check for. There is a reason for that.

Labradors are genuinely a high-risk breed

This is not marketing. The American College of Veterinary Surgeons lists the Labrador Retriever among breeds with a known higher incidence of cranial cruciate ligament disease, alongside the Rottweiler, Newfoundland, Staffordshire Terrier, Mastiff, Akita, Saint Bernard and Chesapeake Bay Retriever.

Independent research on breed predisposition in younger dogs has found overlapping results, identifying the Labrador Retriever among predisposed breeds.

So if you have been told "Labs are prone to this," that is accurate — which is unusual enough on the internet to be worth stating plainly.

What "torn ACL" actually means in a dog

The canine equivalent of the ACL is the cranial cruciate ligament (CCL), inside the stifle joint of the back leg.

The critical difference from human ACL injury: in dogs this is usually a degenerative disease, not an accident. The ACVS describes the ligament in most affected dogs as having deteriorated gradually over months or years before it fails. The moment your Labrador yelped chasing a ball was often the end of a long process, not the start of one.

Two consequences follow, and both matter:

1. Partial tears almost always progress to complete tears over time (ACVS).
2. The other knee may also be at risk. Because this is described as a disease of the ligament rather than a one-off trauma, contralateral rupture is a recognised concern in the veterinary literature and a question worth putting to your vet.

Signs to watch for

Per VCA Animal Hospitals, presentations range widely:

• Sudden severe lameness — some dogs will not put the leg down at all
• "Toe touching" — placing only a small amount of weight on the leg
• Intermittent limping that improves with rest and returns with activity
• Stiffness after lying down, easing as they move
• Sitting with the affected leg kicked out to the side rather than tucked
• Reluctance to jump into the car or onto furniture
• Over time, visible muscle loss on the affected thigh

That intermittent pattern is the one Labrador owners most often dismiss. A limp that comes and goes is very consistent with a partial tear — which is the stage where you have the most options.

How it gets diagnosed

Your vet will palpate the knee for abnormal forward movement of the tibia relative to the femur, typically using a drawer test or tibial compression test (VCA). Radiographs are commonly taken to assess joint changes and rule out other causes. Sedation is sometimes needed, because a tense, painful dog can mask the instability.

Labrador-specific factors

Weight is the lever you control. Body weight is an established risk factor in cruciate ligament research, and Labradors are a breed with a well-documented tendency to gain weight. Excess weight increases load on an already compromised joint and complicates both surgical recovery and conservative management. If your Lab is carrying extra kilos, addressing that is not a side note — it is one of the few parts of this you can directly influence.

Size affects the treatment conversation. A survey of ACVS Diplomates and primary-care veterinarians found that treatment recommendations differ by dog size. An adult Labrador sits firmly in the size range where surgical stabilisation is most commonly discussed. That is context for the conversation, not a decision.

Activity level. Labs are often high-drive dogs who will keep running on a painful leg. Activity restriction is genuinely harder to enforce with this breed and is genuinely important.

Your options

Surgical stabilisation — techniques including TPLO (tibial plateau levelling osteotomy), TTA (tibial tuberosity advancement) and extracapsular suture stabilisation. Which is appropriate depends on your dog's conformation and the surgeon's assessment. The University of Florida Small Animal Hospital outlines these approaches.

Conservative management — weight control, controlled activity, physiotherapy, pain management, and sometimes bracing, supervised by a vet or rehabilitation practitioner.

Bracing specifically — we have written honestly about whether dog knee braces are effective. The short version: the evidence is mixed, a brace does not repair anything, and for a large active Labrador it is not a straightforward substitute for surgical assessment. It has a place, usually within a supervised plan or where surgery is not viable.

We will not tell you which of these is right for your dog, because we cannot know. Ask a surgeon — you can find an ACVS board-certified one here.

The meniscus question worth asking

When you speak to your vet, ask specifically whether there is meniscal damage. The meniscus is cartilage within the joint that can be injured alongside a cruciate tear, and its status affects both the treatment recommendation and the outlook. It is a question owners rarely think to ask and vets are always happy to answer.

If you do end up considering a brace

Measure properly. Sizing is not standardised between manufacturers, and measurement error causes more failed braces than product quality does. Our measuring guide covers the three measurements every brand asks for — and note that a Labrador with several weeks of muscle loss on the affected leg will measure differently than they will once muscle returns.

Frequently asked

Will my Labrador tear the other one? Elevated risk is well recognised, because this is ligament disease rather than isolated injury. Ask your vet about monitoring the other knee, and take weight management seriously for exactly this reason.

Can a torn cruciate heal on its own? The ACVS describes cruciate disease as degenerative, with partial tears progressing to complete ones. Functional stabilisation without surgery is discussed more often for smaller, lighter dogs. Where an adult Labrador sits is a judgement for a vet who has examined the joint — ask directly.

How much does surgery cost? It varies enormously by region, technique and clinic, and any figure we quoted would mislead you. Ask two clinics directly and ask what the quote includes.

Should I stop walking my dog? Do not guess at this. Activity restriction is a specific clinical instruction — too much rest and too little are both harmful. Get the plan from your vet.