If a young dog suddenly becomes lame during the growth phase, its gait seems stiff and unsteady and it hardly wants to move, then a bone growth disorder with the medical name osteochondrosis dissecans, OCD for short, can be the cause. In this article you will find out exactly what OCD in dogs is, what the symptoms are and which dog breeds are particularly affected.
Definition – What is OCD in dogs?
Osteochondrosis dissecans (OCD) in dogs is a disease that occurs primarily in medium-sized and large dog breeds during the growth phase, usually from the 5th month of life. This leads to a disruption in bone formation in the large joints of the limbs, mainly in the shoulder joints (in about 3/4 of cases), but also in the elbow, knee or ankle joints.
During growth, soft cartilage tissue is only gradually converted into solid bone mass in the skeleton – if this were not the case, animals or even humans would not be able to grow. With the increasing ossification of the cartilage, the bones also become longer and the skeleton becomes more and more solid. In particular, the large tubular bones of the limbs grow longer than other bones in the body and thus determine the final body size. Since dogs of medium-sized to large breeds in particular grow quite quickly in relation to smaller breeds, there can be disturbances in the ossification of the cartilage tissue.
If the cartilage cells in a healthy dog are broken down with increasing growth and converted into bone by storing minerals such as calcium and phosphorus, this process is disrupted in a dog suffering from OCD. Instead, the articular cartilage continues to grow and becomes thicker and thicker. However, since cartilage, in contrast to bone, is not supplied with nutrients directly via blood vessels, but rather by diffusion from the surrounding synovial fluid (= synovia), the increasing thickness of the cartilage layer leads to an undersupply of nutrients and the affected cartilage eventually dies.
Due to the mechanical stress in the joint caused by the movements of the dog, small spaces between the bone and the cartilage layer, so-called fissures, develop. As the disease progresses, small pieces of the dead cartilage finally partially or completely detach and move as cartilage scales or “joint mice” within the joint capsule. Over time, these cause painful inflammation in the joint. The dog becomes increasingly reluctant to move and finally shows a clear lameness.
As the OCD progresses in dogs, the free cartilage scales can continue to grow and ossify. In the long term, this causes painful arthrosis. Since the clinically visible signs of the disease are only recognizable with a time lag, the diagnosis is usually made one to four months after the suspected onset of the bone formation disorder.
What is OCD in dogs?
OCD (=osteochondrosis dissecans) is a joint disease that occurs primarily in medium-sized to large dogs during the first year of life.
Genetic predisposition? These dog breeds are often affected
Several different factors are usually responsible for the development of OCD. However, there is much to suggest that there is a genetic disposition for this disease in fast-growing medium-sized and large dog breeds, i.e. the disruption of endochondral ossification is hereditary. Dog breeds that tend to have this defect include:
- German shepherd dog
- German Mastiff
- Belgian shepherd
- Rhodesian Ridgeback
- Boxer
- Rottweiler
- Labrador Retrievers
- Golden retriever
- Newfoundland
Male dogs are affected by OCD much more frequently than female dogs. The breeding associations of the affected breeds usually carry out appropriate breeding suitability tests on potential parents in order to prevent the passing on of genetic defects such as OCD as far as possible. So if you want to get a puppy of an affected breed, you should only buy it from a responsible, reputable breeder who can show proof of the appropriate examinations of his breeding animals.
However, since this bone formation disorder can also occasionally occur in smaller and lighter dogs, genetic disposition does not appear to be the sole cause of OCD. It is therefore a multifactorial event.
Causes – why does OCD develop in dogs?
In addition to the hereditary component in the dog breeds mentioned, other factors also play a role in the development of OCD, some of which can even be influenced by the dog owner. Above all, a wrong diet during the growth phase of the young dog promotes disorders of the musculoskeletal system.
On the one hand, if the energy content of the food is too high, it can unnaturally accelerate the dog’s growth. As a result, the bones simply do not have enough time to develop physiologically. At the same time, the dog’s rapidly increasing body weight puts additional strain on the joints, which aggravates the problem.
An incorrect nutrient composition in the feed also promotes disturbed bone growth. Above all, the concentration of the minerals calcium and phosphorus in connection with the vitamin D content plays a decisive role. While the minerals are stored in the bones and thus give them the necessary strength, the body needs vitamin D in order to first absorb enough calcium and phosphorus from food. Especially during growth, it is particularly important to ensure a balanced composition of these nutrients in dog food.
So that the calcium absorbed from food can finally be stored in the bones, different hormones have to be activated in the body. Estrogen and testosterone in particular, but also hormones from the adrenal glands and the thyroid play a role in bone growth. A disturbed hormone balance, for example in diseases of the thyroid gland or the adrenal glands, also has a direct influence on growth and bone formation.
And finally, purely mechanical factors also play a major role. If a young dog is physically very demanding, for example through wild playing with fast running and abrupt changes of direction or even through intensive use in dog sports, extremely large forces act on the not yet fully developed joints. Tiny tears, fissures or even fractures in the cartilage tissue can be the result. In the worst case, this can lead to permanent joint damage.
What does OCD-free mean in dogs?
Various breed associations prescribe medical examinations for the breeding approval of their dogs, with which the presence of certain hereditary diseases is to be ruled out. If a breeding dog is declared OCD-free, the veterinarian did not find any indication of the presence of OCD during the breeding suitability examination.
Symptoms of OCD – Early Detection
The earlier osteochondrosis dissecans is detected in young dogs, the greater the chances of successfully treating this disease conservatively. In fact, at a very early stage, OCD can heal spontaneously without any clinical symptoms occurring in the dog at all.
However, since the symptoms that are clearly visible to the dog owner, such as a lack of movement, lameness or even swelling of the affected joints, usually only appear in an advanced stage of the disease after about 1-4 months, OCD almost always requires medical treatment.
The most important symptom is the onset of sudden and pronounced lameness in the young dog. Although the disease is present on both sides of the respective joints in the majority of cases, most affected dogs are initially lame on one side. The gait seems stiff, the dog takes significantly shorter steps. This lameness occurs after periods of rest as well as after exercise.
Especially the OCD in the elbow joint is usually very quickly recognizable for the dog owner due to the acute lameness that occurs. Changes in the shoulder, knee or ankle joints usually only become apparent a little later. Only further examinations by a veterinarian can clarify the exact cause of the lameness.
Diagnosis of OCD in the dog
The veterinarian will first assess the dog’s movement before conducting an examination of the bones and joints. As a rule, the swelling of the affected joints due to the inflammatory processes can already be determined during palpation. Passive flexion and extension causes pain to the dog and is another clue to the condition.
To confirm the suspected diagnosis, X-rays of the affected joint are taken, if possible from both limbs. Even if the lameness often only affects one side at first, bilateral lesions of the corresponding joints must always be assumed. In many cases, the X-rays already show clear indications, such as a cartilage scale or an insufficiently mineralized area of the bone, which secure the diagnosis. Further examinations such as CT diagnostics should only be carried out for definitive confirmation if the findings are indistinct or unclear.
It is true that the best diagnostic results can be achieved with magnetic resonance imaging (=MRT), since a very detailed representation of the individual joints is possible here. However, only large clinics are usually equipped with this expensive technology. And an arthroscopy (=joint reflection) is usually only carried out in specially equipped small animal clinics.
Treatment of OCD in dogs
If OCD is detected at a very early stage, it may be possible to prevent worse from happening with conservative therapy (and without an operation). In addition to the administration of anti-inflammatory drugs and a precise analysis and adjustment of the feed composition, the dog is kept as calm as possible.
The affected joint may be moved as little as possible over a period of at least three months in order to allow the lesions that are already manifest to heal. This means that the young dog is only kept on a short leash and, if possible, is only given a very limited range of motion indoors.
At the same time, physiotherapeutic exercises can be used to counteract the breakdown of the muscles caused by the restricted movement. The additional use of painkillers makes the disease more bearable for the dog, but has the disadvantage that it no longer rests and thus moves the joint too much.
In the case of more advanced OCD with damage clearly visible in the X-ray image and cartilage scales within the joint capsule, only a surgical intervention can help. Depending on the severity of the case and which joint is affected, either the joint capsule is surgically opened or an arthroscopy is performed using a minimally invasive procedure. During the operation, all cartilage fragments are removed from the joint capsule and the bone is carefully smoothed to stimulate healing of the defect.
Even after the surgical treatment, the dog must be sedated for at least six weeks. So also as little exercise as possible and strict leash compulsion when going for a walk. In order to prevent excessive muscle loss, physiotherapy should also be used with the dog after the operation.
How much does an OCD surgery on a dog cost?
Depending on the severity of the joint changes, such an intervention leads to more or less high costs. Joint surgery usually costs between $1000 and $2000.
After the treatment: will my dog remain pain-free?
Whether a dog remains pain-free after treated OCD depends on the severity of the disease at the time of treatment. But the localization of the OCD, i.e. which joint is affected, also plays a major role in the prognosis. For example, dogs that have undergone surgery for OCD of the shoulder joints often have a very good recovery.
Nearly normal joint function can often be achieved. If, on the other hand, the defect occurs in other joints such as the elbow, knee or ankle, the damage is often so advanced that it cannot be fully repaired. These dogs require a lifetime of drug treatment to be able to move about with reasonably little pain.
If the OCD has been treated conservatively, the dog can still become lame again and again, since the degenerative processes in the joint, i.e. the breakdown of the cartilage and the deformation of the bone, have already progressed too far and in some cases even continue. In any case, even after treatment and improvement of the symptoms, a dog should only be moved and exercised moderately. Use as a working dog or in dog sports is not advisable for such dogs – on the contrary, it may even be relevant to animal welfare, since a dog with OCD and the resulting arthrosis can suffer from joint problems and pain for the rest of its life.
Due to the suspected genetic disposition in medium and large dog breeds, dogs diagnosed with OCD should under no circumstances be used in breeding to prevent the disease from being passed on. For dog breeds in which the heredity of the OCD is already considered to be almost proven, the responsible breeding associations usually already prescribe corresponding medical preliminary examinations of the potential parent animals.
Effective measures to prevent OCD in dogs
Since OCD is a multifactorial disease, the occurrence or at least the severity of the symptoms can be influenced by a few preventive measures. First and foremost, owners of medium-sized to large breeds should make sure not to exercise their dog excessively or even to overload it in the first months of life until the musculoskeletal system has finally matured.
Particularly playful activities that require fast running, abrupt changes of direction or overcoming high obstacles should be avoided if possible in the first year of life. Even regular stair climbing can be disease-causing in dogs that are predisposed to OCD.
With some breeds that are particularly active, such as German shepherds, it is not easy to keep the young dog’s level of movement permanently at a low level. For these breeds in particular, it is often advised to train the dogs in various dog sports disciplines so that they can work off their exuberant energy.
In view of the susceptibility of these fast-growing dog breeds to various diseases of the musculoskeletal system, of which OCD is just one, challenging sporting activities should be consistently avoided during the all-important growth phase. If the particularly sensitive phase of the first 10-12 months of life is over, the dog owner has already done a lot to significantly reduce the risk of osteochondritis dissecans.
Equally important for minimizing the causes is a particularly balanced diet tailored to the needs of the growing dog. Excessive energy intake in the form of protein should be avoided, as should an unbalanced ratio of the nutrients contained. Above all, the correct calcium, phosphorus and vitamin D content is crucial for normal, healthy development of the skeleton and thus helps to prevent the development of OCD or other diseases of the musculoskeletal system. A precise analysis and feeding advice from the treating veterinarian can be helpful.
