Muscle and bone disorders in dogs and cats

Muscle and Bone Disorders in Dogs and Cats

Contents:		Brought to you by...
Arthritis Avascular Necrosis of the Femoral Head Care of Fractures Cranial Cruciate Ligament Rupture Hip Dysplasia Intervertebral Disc Disease	Panosteitis Patellar Luxation Rheumatoid Arthritis Rickets Umbilical Hernia	Back to home page

Back to health info table contents

Arthritis

General Information: Arthritis is inflammation of a joint. It can occur in any joint, including the spine and jaw. Signs of arthritis include painful or stiff joint movement, joint swelling and a grating sensation during joint movement. Arthritis can also cause fever and redness of the skin over the joint.

Polyarthritis is inflammation of several joints at the same time. It is often associated with complex internal diseases.

Causes of arthritis include degeneration from aging, inherited arthritis, infection, injury, blood diseases, allergic or immune-mediated disease, and cancer.

Radiographs (x-rays) and laboratory tests are necessary to determine the type and extent of the arthritis. Follow-up examinations during treatment are necessary to evaluate the response to therapy. Arthritis is usually a controllable rather than a curable disease. Therapy is designed to minimize discomfort and delay or prevent progression of disease.

Notify your veterinarian if any of the following occur:

Your pet’s discomfort or lameness increases.
Your pet is reluctant to eat or seems unusually thirsty.
There is swelling or drainage from a joint.

Avascular Necrosis of the Femoral Head

General Information: Avascular necrosis is a disease of the hip joints of miniature and toy breeds of dogs, most often in poodles. It develops between 4 and 12 months of age. The disease causes bone destruction in the hip joint, resulting in a roughened, irregular joint surface. Moving the rear legs causes pain, and the leg muscles weaken and shrink from insufficient use. Occasionally the limbs actually shorten. One or both rear legs may be affected. If only one leg is involved, the dog usually refuses to bear any weight on that limb.

Avascular necrosis is hereditary and probably results from breeding for small body size. This selective breeding produces dogs that mature more rapidly, and the early effects of hormones on the developing hips may cause the disease. Some researchers also believe that injury to the developing hips may cause the condition.

If the condition is not treated, the dog may develop severe arthritis in later life.
1. Symptomatic treatment: This is designed to relieve pain and discomfort during recovery in mild cases.
2. Surgical treatment: Excision arthroplasty is the surgical removal of the ball portion (femoral head) of the ball and socket hip joint. It is used to treat more severe cases. A "false joint" of fibrous tissue then forms. This often increases both comfort and mobility. Mild exercise is advisable immediately after surgery, but keep your pet restrained on a leash.

Notify your veterinarian if any of the following occur:

Your pet’s discomfort or lameness worsens.

Care of Fractures

General Information: Certain basic principles apply to fracture care, whether the injury is simple or complicated. These principles include:

Reduction of the fracture: placing the broken ends together.
Fixation of the fracture: fastening any fragments in place.
Immobilization of the limb: keeping the parts motionless during the healing period.

To help your veterinarian employ these principles and achieve satisfactory healing, you must conscientiously follow home care instructions. Keep your pet away from wet grass, puddles, or damp ground. On rainy days, protect the splint or cast with a plastic trash bag. Remove the protective covering when indoors. Keep your pet away from dirt, piles of trash, garbage, or leaves. Isolate your pet from hazards such as throw rugs, slippery floors, and stairs. Remove objects or projections on which the splint or cast may get entangled. Notify your veterinarian if any of the following occur:

The cast or splint becomes wet, damaged, or soiled.
Your pet chews away part of the cast or splint.
The pin, wire, or splint is bent, broken, or loose.
Your pet seems uncomfortable.
Your notice a bad odor from the cast or fracture site.
The cast slips down on the limb.
The limb is swollen or discolored above or below the cast.

Remember: Successful fracture healing depends greatly on home care.

Cranial Cruciate Ligament Rupture

General Information: A ligament consists of tough, fibrous tissue connecting two bones. In the knee, rupture of the cranial cruciate ligament allows the femur (thigh bone) to slide back and forth over the tibia (shin bone).

The rupture first causes pain, then abnormal wear and tear lead to arthritis. This sequence of events occurs most frequently in overweight, middle-aged to old dogs.

Depending on the severity of the rupture, treatment may consist of limited exercise and rest or surgical repair of the torn ligament. Ordinarily no special diet is required for healing. If your pet is overweight, weight reduction can speed recovery and possibly prevent further injury.

Notify your veterinarian if any of the following occur:

Your pet seems to be in pain or is uncomfortable.
Your pet chews or damages the splint/bandage or stiches.

Hip Dysplasia

General Information: Hip dysplasia is a condition in which abnormal formation of the hip joint results in unstable hip joint. As the affected dog ages, the hips gradually become arthritic and may degenerate to cause total crippling of the rear limbs.

The exact cause is unknown, but it is believed to develop because the skeleton grows faster than the supporting muscles. The imbalanced growth rate is influenced by heredity and diet. Other unknown factors may influence the development and severity of hip dysplasia.

Not all dogs with hip dysplasia are affected to the same degree. The disease can be very mild and cause no signs at all, or it may be severe and crippling of the rear limbs. While the disease usually affects both hips, occasionally it only affects one side. Hindleg lameness, a swaying or swaggering gait, "bunny-hopping" while running, discomfort on rising, reluctance to climb stairs or stand on the rear legs, and reluctance to run or jump are all signs of hip dysplasia. Though this disease is most common in large breeds of dogs, it may occur in any breed.

Depending on the severity of the condition, treatment may require surgery or simply restricting exercise. Proper treatment often allows affected pets to live reasonably normal lives.

Notify your veterinarian if any of the following occur:

Your pet shows increasing discomfort or lameness in the rear legs.
Your pet develops weakness or lameness in the front legs..
Your dog has vomiting, increased urination, or increased water intake.

Intervertebral Disc Disease

General Information: The spine is made up of bony segments called vertebrae, which are joined by ligaments, muscles, and fibrous structures called intervertebral discs. The intervertebral discs act as shock absorbers between vertebrae. A disc consists of a fibrous outer ring and an inner section that is soft and jelly-like. The fibrous outer ring is thinner at the top portion than it is at the bottom. When a disc becomes diseased, either through gradual degeneration or injury, the thinner top portion of the outer ring gives way, and the disc bulges into the spinal canal located directly above the disc. If the disc ruptures completely, the outer ring collapses and the inner jelly-like portion is forced into the spinal canal. The spinal cord is located in the spinal canal. A bulging or ruptured disc causes pressure or damage to the spinal cord, resulting in pain, weakness, uncoordination, or paralysis.

Intervertebral disc disease is diagnosed by physical signs, neurological tests, and radiographs
(x-rays). In some cases, a dye must be injected into the spinal canal so that areas of damage will show up on the radiographs. This procedure is called myelography.

Both medical and surgical treatments are used for intervertebral disc disease. Such factors as age, severity and duration of signs, neurological findings, and physical status help determine whether surgery should be performed. In many cases, hospitalization is necessary for effective medical treatment. If your pet is overweight, weight reduction is desirable since excess weight puts additional strain on the back. In all cases, less food is necessary during the treatment period due to the exercise restriction.

Notify your veterinarian if any of the following occur:

Your pet is increasingly uncomfortable.
Your pet loses control of its bowel movements or is constipated.
Your pet has difficulty urinating.
Your pet has breathing problems, rigid front legs, or seizures.

Panosteitis in Dogs

General Information: Panosteitis is a disease primarily affecting young dogs of large breeds. It is characterized by inflammation within bones, especially those of the legs. Lameness of one or more legs is often apparent.
The disease may persist for 1-6 months, with the average case lasting 2-3 months. During the course of the disease, periods of pain and lameness are interrupted by intervals of good health. Lameness may switch from one leg to another, and the degree of discomfort may vary. Full recovery is common.

Panosteitis is considered a self-limiting disease. This means recovery occurs after the disease runs its course. The only treatment presently used is oral anti-inflammatory or pain releiving drugs. Repeated radiographs (x-rays) may be required to evaluate the progress of the disease. Inactivity is to be expected during the painful periods of the disease. Liniting exercise during this time is beneficial. There is no need to restrict your pet’s activity during the non-painful time.

Notify your veterinarian if any of the following occur:

Your dog’s legs become swollen.
Your dog seems unusually uncomfortable.

Patellar Luxation

General Information: Patellar luxation is a dislocation of the kneecap (patella). The kneecap may dislocate toward the inside (medial) or outside (lateral) of the leg or may move in both directions.

The crippling effects of patellar luxation are related to the severity and duration of the luxation. The milder forms, especially in small breeds, show little or no signs, and only minimal treatment is required. Severe cases cause more intense pain, with limping.

Treatment ranges from rest (decreasing your pet’s activity for 1-2 weeks) to surgical reconstruction of the knee joint. Treatment is based upon the severity of signs and your pet’s age, breed, and weight. Obesity complicates surgery and convalescence. A weight-reduction program may be required in conjunction with treatment.

Notify your veterinarian if any of the following occur:

Your pet seems unusually uncomfortable.
Soreness and/or swelling of the joint increases.
The leg opposite the affected one becomes lame.

Rheumatoid Arthritis

General Information: Rheumatoid arthritis is an uncommon joint disease that usually affects small or toy breeds of dogs. It can affect dogs as young as 8 months of age.

The disease first appears as lameness that changes from leg to leg, with swelling of the affected legs. Within weeks to months, the disorder settles in particular joints. Radiographs (x-rays) of involved joints show destruction of bone. As the disease progresses, the joints may dislocate and appear deformed.
The cause of rheumatoid arthritis is unknown, but the disease probably results from a defect in the immune system.

Rheumatoid arthritis is a difficult disease to treat, and lifetime treatment is usually necessary. The condition may Improve dramatically at first, but as time passes, it may become unresponsive. Very potent anti-cancer drugs are often used in treatment. This necessitates close monitoring of the dog’s general health with periodic laboratory tests. The pain of rheumatoid arthritis naturally restricts activity. Do not force your pet to exercise or allow it to jump from furniture, steps, etc.

Notify your veterinarian if any of the following occur:

Your dog’s signs recur after apparent recovery.

Rickets

General Information: Rickets is a disease of young, growing animals. It is characterized by improper bone development. Typical signs include swelling of the joints and bending or bowing of the bones in the legs. Fractures occur easily because of poor bone development.

Rickets is caused by a dietary imbalance of calcium, phosphorus, and vitamin D. Because most dogs are fed commercial dog foods that are properly balanced, the disease is not common. Improper mineral supplementation or a diet high in meats can cause rickets.

Diet control is extremely important in treating rickets. Do not make any diet changes without consulting your veterinarian.

Notify your veterinarian if any of the following occur:

Your pet refuses to use one or more legs.
Your pet becomes increasingly weak.

Umbilical Hernia

General Information: An umbilical hernia is the protrusion of abdominal contents beneath the skin at the navel (umbilicus).
The umbilicus is the healed scar ("belly button") in the mid-abdominal area. It marks the opening through which the prenatal blood vessels and other fetal structures passed before birth. After the umbilical cord is cut at birth, the opening rapidly closes. Occasionally, however, it does not close completely, and an opening in the abdominal wall remains.

The danger of a hernia is the potential entrapment of intestines through this opening. If the hernia interferes with the blood supply to the trapped bowel, passage of food through the bowel is blocked. Also, the strangulated tissue dies and releases toxins that may kill the animal.

Most small hernias are no danger to your pet’s health. Some may close before the animal reaches maturity; therefore, no treatment is necessary. Occasionally, surgical repair is delayed in female dogs until it is performed at ovariohysterectomy (spaying). Large hernias may be very serious, since a portion of intestine may become entrapped and its blood supply cut off.

Notify your veterinarian if any of the following occur:

You observe redness and tenderness at the hernia site.
Your pet vomits or shows sudden signs of distress.
Your pet has painful or difficult bowel movements.