Limping is a sign of an injury or debilitation of one or more parts of the leg. The injury could be bone, muscle, nerves, tendons, ligaments or skin, and may be anywhere along the front or back leg regions (elbows, wrists, hips, knees, ankles and toes) so there are many different possible causes.
Some injuries are obvious especially if external – like broken bones or penetrating wounds or lacerations – but others have no visible signs.
You’ll need to see your vet to determine the underlying cause through a proper diagnosis. Although not a comprehensive list, the most commonly seen causes of limping seen in dogs are:
Soft Tissue Injury
These include sprains, strains, muscle injury, trauma or bruising. The majority of limping issues fit into this category, and typically result from trauma or overuse – anywhere from tripping or slipping, falling, car accidents to injuries in the dog park.
When minor, these soft tissue injuries tend to resolve themselves with rest over a short period of time. Some of these injuries require nonsteroidal anti-inflammatories (NSAIDs) from your vet to help settle them and keep your dog comfortable while healing.
It’s also worth mentioning that with puppies, sometimes they will be acutely restless and whining when injured – keep them calm and wait 1 hour to see if limping still persists. Often they are responding to the initial shock of the injury – but if the leg still looks bothersome after an hour, you’ll want to closely watch the leg and refrain from any exercise for a while.
Pro Tip: Keep puppies calm and wait 1 hour to see if limping persists. This helps determine the severity of the injury.
Osteoarthritis or Degenerative Joint Disease (DJD), aka “Arthritis”
Inflammation of the joints is often a result of another underlying cause, such as hip dysplasia or elbow dysplasia or an old trauma, etc. It presents with stiffness or limping particularly after rest. It usually eases with gentle exercise and is often aggravated with strenuous exercise.
“ACL tear” or Cranial Cruciate Ligament Injury
This is one of the most common hind leg injuries seen in dogs. It usually presents as an initial non-weight bearing lameness (not putting weight on the leg), then within a day, they start to put more weight on it (often “toe-touching”), but still obviously limping.
If left alone, the limping will often continue to improve, but will return if the dog does any strenuous exercise. Long term, an untreated ACL tear will likely lead to muscle loss, arthritis, and decreased activity. Any lameness like this should be seen by a vet as early intervention can help with the long-term outcome.
Shoulder Injury
There are many ligaments and joint capsules as well as bursa and tendon sheaths within the shoulder joint that can get torn or injured (particularly with splaying motions and over-extension).
These can also be caused by a breed predisposed condition (typically in large breed dogs). These can present as intermittent (off and on) limping in one or both front legs.
Elbow Dysplasia (and Arthritis of the Elbow(s))
A joint disorder typically affecting one or both front legs, elbow dysplasia typically presents as an intermittent limp (on and off) and will get worse after exercise. Dogs with elbow dysplasia need x rays to be diagnosed. This is often a hereditary issue that’s more common in certain larger breeds, such as Labrador Retrievers, Golden Retrievers, Rottweilers and German Shepherds.
Hip Dysplasia (and Arthritis of the Hip(s))
A joint disorder in the hips will typically affect one or both the rear legs. It can cause subtle lameness or acute and severe lameness, particularly as it progresses. This is often a hereditary issue (common in certain larger breeds). Other signs include a bunny hop gait when running in the early stages.
Pro Tip: Bunny hopping is typically a sign of early stage hip dysplasia, and should be addressed early with your vet.
Fracture
A broken bone is a serious injury, and most often a dog will not be willing to put weight on a fractured limb. However, it’s not always obvious if it’s only a hairline break (i.e. a small crack) or fracture of a small bone.
Paw (and Paw Pad) Wounds
Foreign objects stuck or penetrating the paw like nails, glass, sticks, rocks, etc. or lacerations to paw pads, or even a bee sting on the paw can cause your dog to limp. Usually in these cases, dogs will lick their paws constantly, and the onset will be sudden.
Food and environmental allergies will often cause paw infections, interdigital cysts (lumps between the toes), and skin lesions that look like cuts. These will often cause dogs to limp.
Neoplasia (Cancer)
Certain cancers that affect the bones (osteosarcoma) can cause limping in dogs. It usually develops gradually, but tends to get progressively worse over time (eventually causing very severe limping). Dogs will often lose weight and may be more lethargic than usual, and medications will not be as helpful. The earlier osteosarcomas are detected the better, so that treatment can start ASAP.
Other less common causes of limping include auto-immune diseases, Lyme disease, and other infectious diseases, as well as septic infections that cause inflammation of the joints, and thus limping.
These can be a “shifting lameness” where different limbs are affected at different times, and your dog may also have swollen joints. They usually coincide with other symptoms like fever and lethargy. These are diagnosed by doing blood work and other diagnostic tests with your veterinarian.