Cruciate Disease in Large Breeds:
The knee is a fairly complicated joint. It consists of the femur above, the tibia below, the kneecap (or patella) in front, and the bean-like fabellae behind. Chunks of cartilage called the medial and lateral menisci fit between the femur and tibia like cushions. An assortment of ligaments hold everything together, allowing the knee to bend the way it should and keep it from bending the way it shouldn't.
Finding the Rupture
The ruptured cruciate ligament is the most common knee injury of dogs. Chances are that any dog that suddenly has rear leg lameness has a ruptured anterior cruciate ligament. The history usually involves a rear leg suddenly so sore that the dog can hardly bear weight on it. If left alone, it will appear to improve over the course of weeks but the knee will be notably swollen and arthritis will set in quickly. Dogs are often brought to the vet in either the acute stage (shortly after the injury) or in the chronic stage (weeks or months later). The key to the diagnosis of the ruptured cruciate ligament is the demonstration of an abnormal knee motion called a drawer sign. It is not possible for a normal knee to show this sign. You must consult with you family veterinarian if your animal shows signs of hind limb lameness.
How this Happens
There are several clinical pictures seen with ruptured cruciates. One is a young athletic dog playing roughly who takes a bad step and injures the knee while playing. This is usually a sudden lameness in a young large breed dog. A recent study identified the following breeds as being particularly at risk for this phenomenon: Neapolitan Mastiff, Newfoundland, Akita, St. Bernard, Rottweiler, Chesapeake Bay Retriever, and American Staffordshire Terrier. On the other hand, an older large dog, especially if overweight, can have weakened ligaments and slowly stretch or partially tear them. The partial rupture may be detected or the problem may not become apparent until the ligament breaks completely. In this type of patient, stepping down off the bed or a small jump can be all it takes to break the ligament. The lameness may be acute but have features of more chronic joint disease or the lameness may simply be a more gradual/chronic problem. Larger overweight dogs that rupture one cruciate ligament frequently rupture the other one within a year's time. An owner should be prepared for another surgery in this time frame. Without an intact cruciate ligament, the knee is unstable. Wear between the bones and meniscal cartilage becomes abnormal and the joint begins to develop degenerative changes. Bone spurs called osteophytes develop and chronic pain and loss of joint motion result. This process can be arrested by surgery but cannot be reversed.
Tibial Plateau Leveling Osteotomy (TPLO) This procedure uses a fresh approach to the biomechanics of the knee joint and is meant to address the lack of success seen with the above two techniques long term in larger dogs. With this surgery the tibia is cut and rotated in such a way that the natural weight-bearing of the dog actually stabilizes the knee joint. As before, the knee joint still must be opened and damaged meniscus removed. The cruciate remnants may or may not be removed depending on the degree of damage. The TPLO rotates (as indicated by the arrow) the sloped tibial plateau until it is perpendicular to the line between the stifle and the hock joint centers This surgery is complex and involves special training in this specific technique. Many radiographs are necessary to calculate the angle of the osteotomy (the cut in the tibia). At this time, the TPLO is felt to be the best way to repair a cruciate rupture regardless of the size of the dog and is probably the only procedure to be considered for dogs over 50lbs.
General Rehabilitation after Surgery
Rehabilitation after TPLO is gentler. Icing as above and rest are the main modes of therapy. After 3 to 4 weeks, an increase in light activity can be introduced. A water treadmill is helpful. No jumping, running or stair-climbing is allowed at first. Expect the osteotomy site to require a good 6 weeks to heal.
We mentioned the meniscus as part of the knee joint. The bones of all joints are capped with cartilage so as provide a slippery surface where the bones contact each other (if the bones contact each other without cartilage, they grind each other down). In addition to these cartilage caps, the stifle joint has two "blocks" of cartilage in-between the bones. These blocks are called the menisci and serve to distribute approximately 65% of the compressive load delivered to the knee. The only other joint with a meniscus is the jaw (tempero-mandibular joint). When the crucial ligament ruptures, the medial (on the inner side of the knee) meniscus frequently tears and must either be removed, partly removed, or ideally repaired. This is generally done at the time of cruciate ligament surgery and we would be remiss not to mention it. Pets with meniscal damage may have an audible clicking sound when they walk or when the knee is examined, but for a definitive diagnosis the menisci must actually be inspected during surgery. It is difficult to access the menisci and thus repairing a tear in the meniscus is problematic; furthermore, poor blood supply to the menisci also makes good healing less likely. For these reasons, removal of the damaged portion of the meniscus is the most common surgical choice. This leaves some meniscus behind to distribute the compression load on the knee but removes the painful, ineffective portion.
Elbow dysplasia is the most common cause of front limb lameness in the young dog, especially of the larger breeds.
Dysplasia comes from the Greek dys, (abnormal) and plassein (to form). Thus, dysplasia refers to abnormal development, in this case of the elbow joint.
The elbow is formed from the meeting of three bones: the humerus, which is the boney support of the upper limb from the shoulder to the elbow; the ulna, which runs from the elbow to the paw along the back of the limb; and the radius, which supports the major weight-bearing along the front of the lower limb. All three of these bones need to grow and develop normally and at the same rate such that they fit perfectly at the elbow. If there are any abnormalities along these lines or if the cartilage lining the elbow joint does not form properly then "dysplasia" or abnormal formation is the result.
Elbow dysplasia can take several different forms. Specifically, ununited anconeal process (UAP), fragmented medial coronoid process (FMCP), osteochondritis dessicans of the medial humeral condyle (OCD), ununited medial epicondyle (UME), and elbow incongruity all qualify as types of elbow dysplasia that can be present individually or in combination. While all of the variations are distinct and probably develop in different ways, they have in common that they produce loose pieces of bone and/or cartilage within the joint that act as irritants much as a pebble does in your shoe! All of these variations also have in common that they are primary problems that invariably lead to the secondary development of arthritis within the elbow. The term "arthritis" simply describes inflammation within a joint. The longer an elbow joint is ill-fitting or irregular, the more arthritis forms.
While traumatic episodes may affect the development of the elbow joint, the vast majority of elbow dysplasia cases are genetic in origin.
The first sign of a problem is a mild to moderate front limb lameness in a young dog between the ages of 4 to 10 months. If the problem is not diagnosed at this stage, more marked lameness may be noted as severe arthritis sets in. Large breed dogs predominate.
The use of an arthroscope provides the preferred means of diagnosis and treatment for many cases of elbow dysplasia. Some cases may be managed with open joint surgery and still others may do well with medications alone such as anti-inflammatories. Early surgical management of these problems provides the best chance for minimizing arthritic changes in these elbows, but it must be conceded that virtually all dysplastic elbows will develop some degree of arthritis. Older dogs, where arthritis is well established, may still benefit to some degree from arthroscopic surgery but the benefits are less predictable. The newest generation of canine anti-inflammatory drugs along with chondroprotectives such as glucosamine and diets high in omega-3 fatty acids can also provide some relief. Elbow replacement is an exciting new treatment that has been developed in the last couple of years and, although not widely available, holds great promise for the future.
Hip dysplasia is a common condition of large breed dogs and anyone owning a large breed dog or considering a large breed dog as a pet should become familiar with this condition. The larger the dog, the more likely the development of this problem becomes, particularly as the dog ages. The following is a review of this disease.
So What is Hip Dysplasia?
The term dysplasia means abnormal growth, thus hip dysplasia means abnormal growth or development of the hips. Hip dysplasia occurs during the growing phase of a puppy, usually a large breed puppy, and essentially refers to a poor fit of the ball and socket nature of the hip. The normal hip consists of the femoral head (which is round like a ball and connects the femur to the pelvis), the acetabulum (the socket of the pelvis), and the fibrous joint capsule and lubricating fluid that make up the joint. The bones (femoral head and acetabulum) are coated with smooth cartilage so that motion is nearly frictionless and the bones glide smoothly across each other's surface.
What Causes Hip Dysplasia?
The primary cause of hip dysplasia is genetic but inheritance of this trait is not as simple as a dominance/recessive relationship like we study in high school biology. Normal dogs can breed and yield dysplastic offspring as the condition may skip generations. Until a test based on the actual DNA can be developed, the best we can do to prevent this disease is to breed only dogs with normal hips (a challenge since often dogs are not apparently dysplastic until they have already started a breeding career.)
Nutritional factors are also important in the development of hip dysplasia. For example, it has been popular to try to nutritionally "push" a large breed puppy to grow faster or larger by providing extra protein, more calcium, or even just extra food. Practices such as these have been disastrous, leading to bones and muscle growing at different rates and creating assorted joint diseases of which hip dysplasia is one.
Treatment Of Hip Dysplasia
Hip dysplasia is a very progressive and painful disease. There continues to be medical and surgical means to treat and manage hip dysplasia. Consult with you family veterinarian to discuss all surgical and medical options.
Panosteitis is not a primary bone disease but a disease of the fatty bone marrow with secondary effects involving bone. It affects primarily long bones, but can affect any bone that has significant marrow tissue. The cause for this condition remains unknown but there is degeneration and regeneration of fat cells within the marrow cavity which result in clinical signs as well as radiographic signs. The condition is cyclic in nature, waxing and waning, under conditions of stress. Studies indicate a relationship between the incidence of panosteitis and the commercialization of various protein-rich, high-calorie dog foods. The theory is that an excessive accumulation of protein causes edema due to its osmotic effects. Because bone is a rigid compartment, this leads to an increase in pressure and compression of blood vessels.
Physical examination findings may include shifting leg lameness, fever, and pain. Frequently one limb is more consistently affected. The first incidence of lameness may be associated historically with a suspected trauma, or heavy activity such as running in the park. It can also be associated with the first heat cycle in the bitch. Generally the lameness subsides over a 2-week period of time to reoccur about 3 to 4 weeks later.
Radiographic signs are not always present when lameness is first noticed as there is a lag period of 5-7 days between the onset of clinical signs and the onset of radiographic signs. The clinical period lasts about 2-3 weeks. The radiographic course lasts 3-4 weeks, so there is usually a period of time at the beginning of the clinical course where there are clinical signs and not radiographic signs and at the end of the course there is a period where there are radiographic signs and no clinical signs. Therefore severity of lesions does not correlate with severity of clinical signs.
The disease is self-limiting resolving itself in most dogs at the time of sexual maturity; however, some animals may experience phases throughout their life.
Disease description in this species:
Panosteitis is a disease of the long bones of mostly young, growing large breed dogs, especially those from 5-18 months of age. But even younger dogs and dogs as old as seven years of age have been reported to be afflicted.
Panosteitis is frequently found in dogs with an abnormal factor VIII or von Willebrand's disease and therefore dogs with Panosteitis should be checked for von Willebrand's disease.
Genetic, hereditary, Idiopathic, unknown, Stress, Von Willebrand's disease.
Basset Hound, German Shepherd, Giant breed dogs, Golden Retriever, Labrador Retriever, Large breed dogs, Saint Bernard
Spondylosis (hypertrophic Spondylosis) is a noninfectious, nonseptic condition that is characterized by the formation of bony spurs and bridges in between vertebral bodies of the spinal cord. The condition is a degenerative condition of the spinal cord segments associated with proliferative changes and pain. The condition may be present anywhere in the spine but is most common in the thoracic and lumbar vertebrae.
Spondylosis rarely causes neurologic signs : however, it will cause spinal pain, especially after exercise. It will occur in most species but is most frequent in dogs, bulls, pigs. Dogs will present for lethargy, difficulty getting up after exercise, excessive panting and overall discomfort.
Spondylosis management involves multimodal pain protocols, including but not limited to: non-steroid anti-inflammatories, nutritional management, acupuncture, massage and supplements.
Wobbler's syndrome (cervical spondylopathy, cervical spondylomyelopathy, cervical vertebral malformation) is a very common syndrome affected the cervical vertebrae. This disorder appears with greater frequency in Great Danes and Doberman Pinchers but has been recognized in several other breeds of dogs.
In affected animals neurologic signs develop because of progressive spinal cord compression from surrounding vertebral bony and soft tissue structures. Malformation of the cervical vertebrae results is stenosis (narrowing) of the vertebral canal. This malformation are more consistently present in young Great Danes and include narrowing and flattening of C5, C6, C7. The sixth cervical vertebrae (C6) is usually most severely affected. Another aspect of this syndrome involves malarticulation and vertebral instability.
Clinical signs develop at 3-18 month of age. Male dogs are considered pre-disposed. Dogs typically develop mild pelvic limb weakness and abnormal gait. As the disease progresses severe weakness and paralysis may develop.
The diagnosis is confirmed radiographically as well as MRI/CT. The Syndrome is multi-faceted with many different causes of cervical instability and spinal cord compression.
Dogs with mild neurological signs improve with cage rest and medications. The best long term treatment involves surgical stabilization and /or decompression. The prognosis is guarded and depends on many different factors including: irreparable spinal card damage, failure to provide adequate decompression / stabilization, post surgical complications to name a few.