Arthritis in Older Animals (Osteoarthritis)
Arthritis is a term used to describe the inflammation of joints. Osteoarthritis is a term for long-term or chronic inflammation and slow deterioration of the surrounding joint cartilage within the joint, which is progressive and permanent. This is also known as degenerative joint disease (DJD).
There are two divisions of osteoarthritis, primary and secondary. Primary is very rare and characterized as a genetic malformation of the joints with no known cause. (idiopathic osteoarthritis). This was once studied in depth in a colony of beagles, which you can read about more here. Secondary can be either due to congenital disorders seen in younger animals, animals presenting with DJD signs when older, or secondary to trauma at any age.
Some common causes for canines include:
- Hip Dysplasia
The abnormal development of the hip
- Elbow Dysplasia
The abnormal development of the hip
- Osteochondritis Dissecans (OCD)
The abnormal development of bone and cartilage, leading to a flap of the cartilage within the joint
-Dislocation of the kneecap (patellar luxation)
-Congenital shoulder dislocation (shoulder luxation)
-Cranial cruciate ligament rupture of the stifle (knee)
-Noninflammatory necrosis involving the femoral head with collapse of the bone
This is a death of tissue around the ball of the hip joint which collapses the bone over time. This is known as Legg-Calbe-Perthes disease.
Some common causes for felines include:
-Dislocation of the kneecap (patellar luxation)
Abnormal development of the hip
-And various joint diseases (arthropathy)
The most common symptoms in dogs is a decrease in activity level with an unwillingness to perform basic tasks with intermittent lameness or stiff gait with slow progression. This lameness or abnormal gait may be exaggerated with exercise, long period of laying down and resting, or with cold/wet weather. An unwillingness to use the affected leg(s) with a decreased range of motion may also be seen. Some signs that might be difficult for owners to notice is grating with joint movement (crepitus), joint swelling (joint effusion) and some thickening of the joint capsule. Joint pain with instability is also apparent, but difficult to detect in some animals.
Common symptoms in cats can be similar to dogs, but they may also have difficulty grooming, jumping onto furniture, increased irritability and accessing the litterbox (especially if it is high, or has a high lip; this can also lead to inappropriate elimination outside of the litterbox.)
Primary arthritis has no known cause. Secondary arthritis is a result of a initial cause including abnormal wear on normal cartilage. (example, secondary to joint instability, abnormal joints, trauma to cartilage or supporting soft tissues) or normal wear on abnormal cartilage (example, secondary to defects in the bone and cartilage (osteochondral defects)).
Dogs who have an increased risks of degenerative arthritis from trauma or age induced arthritis include working or very athletic dogs who put stress on their joints from constant and repetitive movements. Also at risk includes obese dogs whose increased weight will put strain on the joints.
Dogs at risk of congenital arthritis include dogs with disorders that affect collagen and cartilage (hyperadrenocorticism "Cushing's syndrome", diabetes mellitus "sugar diabetes", inadequate levels of thyroid hormone "hypothyroidism", excessively looseness in joints "hyperlaxity", or prolonged treatments of steroids.)
Treatments are varied and are generally case specific and tailored to a specific animal's needs. General overview of potential health care for animals with arthritis include:
-Medication Treatment, this can include steroids, non-steroidal anti-inflammatory
-Physical Therapy, this generally includes maintaining or increasing an animals range of joint motion, passive range of motion exercises, massages, and swimming.
Limiting activity to a level that minimizes aggravation of joints can help to decrease clinical signs. Diet can be a large part of keeping an animal's joints healthy. Weight reduction of overweight and obese pets will decrease stress on arthritic joints. Adding a supplement of omega fatty acids may also decrease inflammation, but always consult a veterinarian before starting your animal on any medication.
Surgical treatments are available for arthritic joints, which can help to improve joint geometry or to remove bone-on-bone contact areas. Surgical procedure of cutting into or entering a joint capsule is known as arthrotomy and is used to remove aggravating causes to joints, including bone and/or cartilage fragments or flaps. Surgeons can use a specialized lighted instrument called an arthroscope to see inside the joint, which helps to diagnose and remove aggravating causes, especially by flushing the joint with fluid. Surgeons can also do reconstructive procedures that help to eliminate joint instability and can correct structural or anatomic issues, generally used in pets with dislocation of the kneecap "patellar luxation". Another common surgery performed is the removal of the femoral head "the ball" of the hip joint in cases of abnormal development of the hip (hip dysplasia). This procedure is known as a "femoral head and neck ostectomy or FHO". Total joint replacements are also performed in pets, although some procedures are still experimental, such as total elbow replacements.
Medications listed in this section is a brief overview of potential medications to help mediate the issues faced by pets with arthritis, and this list is not all inclusive. Medications should always be discussed with your veterinarian for the best possible treatment plan for your pet and to ensure there are no pre-existing issues prior to starting certain medications.
-Nonsteroidal anti-inflammatory drugs (NSAIDs) are a common medication used to decrease pain caused by inflammation. These medications must be regulated under care from your pet's veterinarian. Certain combinations of these medications with other medications may cause adverse effects. Never give medications to your pet without consulting your veterinarian. Generally blood work should be performed before starting your pet on these types of medications to ensure there are no pre-existing conditions that would cause further damage by placing your pet on these types of medications. Examples of these medications include: Previcox, carprofen, and meloxicam for dogs and meloxicam or onsior for cats. There are many other medications available, but these are some very commonly used ones in veterinary medicine. With chronic use of these medications, routine monitoring blood work should be performed every 6 months to every year depending on your pets dose and frequency of taking the medication.
-Chondroprotective drugss are medications to slow the progression of arthritic changes and to protect joint cartilage. These medications help to limit cartilage damage and degeneration and can help to alleviate pain and inflammation in the joints. Active ingredients for these medications include: polysulfated glycosaminoglycans, glucosamine, and chondroitin sulfate. Common medication examples include: Adequan, Cosequin, and other glucosamine/chondroitin supplements.
-Steroids can help to decrease inflammation, however, long-term use may delay healing and may initiate damage to joints and cartilage. These medications must be regulated under care from your pet's veterinarian. Certain combinations of these medications with other medications may cause adverse effects. Never give medications to your pet without consulting your veterinarian. Generally blood work should be performed before starting your pet on these types of medications to ensure there are no pre-existing conditions that would cause further damage by placing your pet on these types of medications. Steroids can be given orally or by injection. A commonly used steroid is prednisone or prednisolone. With chronic use of these medications, routine monitoring blood work should be performed every 6 months to every year depending on your pets dose and frequency of taking the medication.
Patients should be monitored for clinical deterioration, which can indicate a pet needs a change in drug selection or dosage, or may even indicate that there is a need for surgical intervention. Early identification of conditions that lead to osteoarthritis and can prompt treatment early that can help to reduce progression of secondary conditions. Slow progression of osteoarthritis is likely for most pets and with medical and/or surgical treatment pets usually have a good quality of life.
Medical therapy of osteoarthritis "palliative treatment" is designed to help control signs of osteoarthritis
, but not to cure the condition. Prognosis of animals diagnosed with oseoarthritis is good, medications and/or surgery can lead to a good quality of life for the pet. The progression is usually slow, and can be slowed further with early detection and early start of supplement medications such as glucosamine/chondroitin supplements. Always discuss treatment options, activity level, and diet with your pet's veterinarian to evaluate your pet's unique needs.