Causes and Treatments of Hindlimb Lameness in Dogs
Lameness in the Hindlimb
This article discusses lameness in the hind legs of dogs. A previous article published here discusses forelimb lameness in dogs. Hindlimb lameness is actually a much more common problem, and accounts for about three quarters of lameness cases in my veterinary hospital.
Much of what I discussed at the beginning of Part 1 regarding wounds, skin infections and nail problems applies to the hindlimb also. The same system of visually inspecting and palpating the structures of the legs should be followed. Muscle strains in the hindlimb are very common, and are most commonly located at the back of the thigh or the calf muscles. If muscle pain is found, the system of resting the leg and icing the injury described in this article should be followed.
The causes of bone pain are the same for the hindlimb as the forelimb. The most common sites for bone tumours in the back leg of the dog are the end of the femur (thigh bone), and the top of the tibia (shin bone); i.e. either side of the knee joint. Dogs with bone pain must be presented to your veterinarian as they will need to be x-rayed.
The most common reason for a dog to limp on a back leg is the presence of joint pain. When examining your dog be sure to flex and extend the ankle (or hock), knee (stifle), and hip joints. You may be able to palpate fluid swelling on the hock and stifle joints if they are injured.
Stiffness after rest usually indicates joint pain, and you may notice your dog 'loosening up' with activity. Lameness which worsens with exercise usually indicates soft tissue pain (muscle or tendon).
Pain in the hock and stifle joints may be first indicated by your dog changing his position when sitting—see image above. The foot is often held out to the side, or the leg may be extended forwards.
Osteochondrosis as a Cause of Joint Pain:
Osteochondrosis is a failure of joint cartilage development, and is seen in young dogs from 4 to 12 months of age who develop a limp that gradually worsens over weeks to months. It typically affects the hock and stifle, leaving an area of bone unprotected by cartilage which rubs painfully when the dog moves its leg. It is most commonly seen in large and giant breed dogs on poor quality food or being fed diets with inappropriate amounts of calcium and vitamin D. Early diagnosis is vital to prevent the development of osteoarthritis.
Problems in the Hock Joint
With the exception of osteochondrosis, most problems affecting the hock joint are the result of a significant trauma such as a road traffic accident, and so the problem will usually be very obvious. Fractures and dislocations of the joint are common, and almost always require surgical repair.
Stifle (knee) Injuries
The most common cause of lameness in active dogs is cranial (or anterior) cruciate ligament rupture (CCL/ACL rupture). The cruciate ligament is responsible for allowing the knee joint to 'hinge' without being unstable. It prevents the shin bone sliding forward when weight is put on the leg. The CCL is usually torn by a combination of braking and turning forces, so it is often seen in dogs that love to chase and fetch.
Without an intact CCL, the stifle joint becomes unstable, bone knocks on bone causing pain, and very often the cartilage 'island' within the joint, called the meniscus, is pinched and torn between the thigh and shin bones. Dogs with CCL rupture usually become suddenly very lame, not bearing weight, and with meniscal injuries there may be an audible 'click' or 'clunk' when the joint is flexed.
While there has been some controversy in the past about the best treatment for CCL rupture, there is now no doubt that dogs with the injury do much better following surgery than those managed without surgical repair. There are many techniques for CCL repair, your vet will advise you on his/her preferred method. Postoperative rehabilitation is at least as important as the surgery and must not be neglected by your veterinarian.
Another very significant problem within the stifle joint is patellar luxation, or a 'slipping kneecap'. It is a problem most commonly seen in small breed dogs such as Terriers and Cavaliers, and presents as a 'skipping' action. Most dogs will walk normally for much of the time, but occasionally (depending on the severity of the problem) pick up one or other hindlimb and skip along on three legs. Many dog owners mistakenly believe that this is normal for their dog, but as with most joint problems, arthritis is likely to develop in dogs with this problem. Again, there are several surgical techniques which may be used to correct the problem. In overweight dogs with mild patellar luxation, weight loss is very often enough to manage the problem.
Causes of Hip Pain in Dogs
The first of two common problems affecting the hip joint is Legg-Calve-Perthes Disease. It is seen in young Terrier dogs, and usually presents in pups between 5 and 8 months of age. Extension of the hip (stretching the leg backwards) is usually very painful. The condition is caused by a failure of the blood vessels 'feeding' the growing head of the thigh bone. The head of the femur forms part of the hip joint, and as it starts to decay without a blood supply, it becomes painful for the dog to move the joint, as each movement causes tiny microfractures of the bone. Surgery is necessary to remove the affected bit of bone; a femoral head and neck ostectomy effectively removes the hip joint, but these small dogs do very well after the procedure and very rarely show any long-term lameness.
Hip dysplasia is the most common disorder of the hip joint, and is usually seen in large breed pedigree dogs such as the Labrador and German Shepherd. The condition is a failure of the hip joint to develop properly, allowing the head of the femur to slip in and out of the joint, causing pain and damage to the joint surface. Signs are often seen in young dogs from 5 to 14 months of age, but often subside when the dog has grown to his/her adult size. However, even in dogs which appear sound after this period, osteoarthritis will develop later in life.
There are several factors involved in the development of hip dysplasia. The first is genetics, as parents with hip dysplasia are much more likely to produce puppies with the condition. For this reason, hip scoring schemes have been brought in by the Kennel Clubs to avoid breeding from affected parents. this has been partially effective in reducing the number of case.
Good nutrition is important; again, calcium and vitamin D amounts must be correct, and it is important that large breed dogs do not grow too quickly, thereby putting too much stress on immature joints. Despite what some eccentrics will argue, a commercial large breed puppy food is the best diet for your large breed puppy. Controlling the type and amount of exercise your puppy gets can also help prevent the condition. Regular moderate exercise rather than infrequent bursts of intense exercise are best.
Treatments for Lameness in Dogs
Although some of these causes of lameness in dogs may benefit from surgical treatment, many dogs with joint injuries may go on to develop osteoarthritis, stiffness, and/or long term lameness. These pets may benefit from medical treatments such as:
- glucosamine & chondroitin supplements, which are very safe and usually the first option I would pursue
- anti-inflammatory medications, but only for dogs without any signs of kidney problems
- opioids such as tramadol
Alternative treatments such as acupuncture may also have a place in treating pets with arthritis, but most veterinarians would see them as being complementary to the type of traditional treatments listed above rather than replacing them.
This article is accurate and true to the best of the author’s knowledge. It is not meant to substitute for diagnosis, prognosis, treatment, prescription, or formal and individualized advice from a veterinary medical professional. Animals exhibiting signs and symptoms of distress should be seen by a veterinarian immediately.