Dogs may have joint disorders right from birth (congenital joint disorders) or they may develop them later from abnormal skeletal growth, injury and infections or due to auto immune diseases. While some joint disorders involve the cartilage, tendons or bursae, others may affect the synovial fluid that is found inside the joint. In arthritis, it is the joint membranes that get affected.
Legg-Calvé-Perthes Disease In Dogs
This disorder prevalent in miniature dogs and other small breeds is characterized by femoral head deterioration. This occurs when blood supply to the head of the thigh bone (femur) is cut off due to the destruction or compression of the small blood vessels supplying it. The exact cause of the disease is not known, but it is thought to be hereditary in some breeds such as the Manchester terrier.
Lameness in the affected hind limb, and pain while moving the joint, are the most obvious symptoms of this disorder. The range movement may be reduced considerably. The thigh muscles as well as the joint become deteriorated in chronic cases.
Diagnosis of the disease can be confirmed with the help of x-rays. The preferred treatment is a surgical procedure called femoral head osteotomy (FHO). The damaged femoral head is removed along with the neck portion. It should be followed up with physiotherapy to regain the normal range of motion of the hip joint.
Kneecap Displacement In Dogs
In this inherited disorder, the knee cap or patella that covers the knee joint gets displaced due to its faulty formation. The hind limbs may have several other deformities in the thigh and shank bones, as well as in the hip, related to this condition. Knee cap displacement disorder is more frequently seen in small breeds of dogs, and the incidence is higher in female dogs.
Lameness or a typical skipping gait is the usual symptom but it may vary according to the severity of the disorder. In some cases, the dislocation is occasional and can be corrected by gentle manipulation. But in advanced stages, the kneecaps rarely stay in their proper positions, resulting in a persistent limp. Other structural deformities may also develop.
The veterinarian can assess the severity of the disease by examining x-ray images of the knee cap displacement and the associated structural deformities. In mild cases, simple surgical procedures may be sufficient to correct the condition and the dogs may recover completely. In case of severe disease, amputation may be the only option.
Osteochondrosis In Dogs
An abnormality in the bone and cartilage formation in young dogs is the cause of this disorder generally observed in larger breeds. It occurs at the time when the young dogs are growing rapidly. The cartilage that is still in the developing stage gets separated from the bone allowing fluid to enter the gap between them. The detached cartilage may develop cysts underneath or get fragmented into small pieces called ‘joint mice’ that float in the fluid, causing irritation and pain, which leads to inflammation and disruption of bone development. Arthritis and severe reduction in joint movement may result. Shoulder joint is the most affected, but it can occur in the knee and elbow joints too.
The exact cause of osteochondrosis is not clear, but rapid development of the bone, often aided by nutrient-rich diet is implicated. Hereditary factors may also be involved.
Typical symptoms are joint pain and inflammation accompanied by stiffness and reduced range of motion that makes the dog lame. X-rays may help the veterinarian to assess the severity of the condition. Another option is endoscopic examination of the joint to get a clearer picture.
The veterinarian may prescribe analgesic and anti- inflammatory medication to manage the pain and inflammation. The separated cartilage and the joint mice can be surgically removed to reduce irritation and movement difficulties. The use of joint fluid modifiers such as hyaluronic acid and glycosaminoglycans has been found to be promising in managing the condition and preventing further deterioration. But they are effective only on long-term use.
If the disease is mild and localized in the shoulder joint, the dog has a very good chance of recovery. But if it has affected other joints in the limbs and is complicated by other joint degenerative diseases, the prognosis is poor.