It is not uncommon for older pets to have chronic lameness (limping) or creakiness from the long-term buildup of arthritis. But lameness is not always an “older pet” issue — certain congenital or developmental problems can cause dogs and cats to limp from a young age.
In certain pets, especially in small breed dogs such as a Chihuahua or Yorkshire terrier, a condition called medially luxating patella can cause lameness. With MPL, the anatomy of the structures around the knee is abnormally formed (usually from a genetic predisposition), which causes the patella, or kneecap, to pop out of its groove. This can often be detected by a veterinarian just by examining and palpating the knee.
Dogs with mild MPL (where the kneecap only pops out occasionally) may just hold the leg up once in a while, or occasionally skip while walking. For these pets, exercise restriction, weight control, and as-needed pain medication can minimize the symptoms.
However, more severe MPL can be debilitating and usually necessitates surgery. Young animals with this condition usually are more mildly affected, but not always. And even if MPL is mild, the problem can worsen with time.
Panosteitis is a markedly painful inflammation of the long bones in the legs and is seen most commonly in younger, growing large-breed dogs (such as German shepherds). The inciting cause is not completely understood.
One or more bones can be affected; if there are multiple areas of inflammation, the lameness may appear to be on different legs at different times. The painful area is usually the shaft of the bone rather than at a joint. X-rays are needed to definitively diagnose this condition.
A dog with panosteitis will usually improve with pain medication and rest, although the recovery may take some time. Until the condition is fully cured, the lameness may flare up from time to time, especially under stressful conditions.
Another painful condition in young dogs and cats is osteochondrosis dissecans, or OCD. This occurs when a piece of cartilage in a joint (such as the shoulder, elbow, or hock) breaks away from the end of the bone, forming a flap. The flap itself may be irritating, as can the grinding of the bone exposed by the cartilage defect. There is a genetic component for the development of OCD, but an energy rich diet and rapid growth can contribute. The cartilage defect may be seen on X-rays or during exploratory arthroscopy/surgery of a painful joint.
In some cases of OCD it may be beneficial to surgically remove the loose cartilage, and in other cases it may be left alone. Secondary arthritis is likely to ultimately develop due to the bone being exposed and traumatized inside the joint
Finally, hip dysplasia and elbow dysplasia can cause lameness in young animals. Hip dysplasia is a loose fit of the “ball and socket” of the hip, causing instability of the joint. This instability is ultimately manifested as limping and through the development of chronic arthritis.
Pets with elbow dysplasia have one or more developmental abnormalities of the bones in the joint (including OCD in some cases), causing pain and inflammation. Both of these conditions have genetic components, and certain breeds are more affected than others. As with some other conditions, X-rays are needed to provide the diagnosis.
If discovered early enough, surgical or medical intervention can lessen the impact of dysplasia and may help reduce long-term arthritis. Surgical options are varied and depend on the exact anatomical abnormalities and the severity of the symptoms.
It would be difficult to argue that there is an epidemic of young dogs and cats with lameness secondary to these and other congenital/developmental abnormalities. However, for those pets that are affected, a rapid diagnosis is vital to institute appropriate therapy.
While early treatment of these conditions may not prevent all future problems (mainly arthritis), even some relief will greatly improve the quality of the many years ahead for a young pet.
— Keith Rode is a veterinarian at Woodland Veterinary Hospital and a graduate of UC Davis. For more information, call (530) 666-2461.