What Is Elbow Dysplasia?
Elbow dysplasia is a congenital condition that starts in puppies and progresses into elbow arthritis as the dog ages. The elbow is a very complicated joint that is comprised of 3 bones that must grow together at the correct rate. If one bone grows quicker or shorter than the other bones, then it can lead to an malalignment called elbow dysplasia. This can lead to boney protuberances that hit the neighboring bones leading to cartilage defects, fragments, and osteophyte formations.
Components of elbow dysplasia includes fragmented medial coronoid process (FCP), ununited anconeal process (UAP), incongruity, and osteochondritis dissecans (OCD). Typically dogs will only have one of these three conditions. Elbow dysplasia can also include elbow incongruity, which is where the radius and ulna grow at different speeds and can lead to FCP or UAP. Poor nutrition (high energy and high calcium diets), genetics and trauma are factors leading to elbow dysplasia, and it commonly affects large and giant breed dogs. Elbow dysplasia is bilateral, but one elbow may be affected more severely.
Fragmented medial coronoid process
Fragmented medial coronoid process is when the medial coronoid process cracks and separates from the ulna. Dogs with FCP typically present between 4 and 7 months of age with a mild to moderate weight bearing forelimb lameness. Physical exam shows pain with elbow extension, elbow flexion, palpation of the elbow joint medially and effusion of the elbow joint. Diagnosis can be made with the Edge-Hughes FCP technique, which assesses for pain when the elbow is compressed while in extension. You may also see pain when internally rotating the antebrachium and flexing the elbow. This will put pressure on the medial aspect of the joint. The lesion may not be seen on radiographs, but may show degenerative changes in the elbow. As the patient ages, there will be general thickening of the elbow joint, decreased range of motion and crepitus (typically dogs older than 11 months). Arthroscopy or CT scan is needed to confirm the diagnosis. Once confirmed, treatment is surgically removing the fragment. There is a better prognosis if surgery is performed prior to the onset of osteoarthritis. However, it is important to note that osteoarthritis is inevitable, but tends to be less severe with surgery. Patients need physical therapy post surgery to reduce swelling, speed healing, improve range of motion of the joint, improve weight bearing, and regain muscle strength.
Ununited anconeal process
Ununited anconeal process is when the anconeal process fails to fuse with the olecranon, which should occur by 5 months old. Dogs with UAP typically present with a weight bearing forelimb lameness. Physical exam shows palpable effusion on the caudolateral aspect of the elbow joint, elbow joint pain especially in extension, and decreased range of motion. Diagnosis can be made with lateral radiographs of the flexed elbow, as well as the Edge-Hughes UAP technique, which assesses for pain when the elbow is as 90 degrees and performing a cranial shear of the ulna on the humerus. Treatment is through various surgical procedures to remove the anconeal process, reattach the anconeal process, or resolve joint incongruity by elongating the ulna. Regardless of which surgery is performed, there will be elbow osteoarthritis.
Osteochondritis dissecans is a disease affecting medium and large breed dogs. It is a developmental disease affecting joint cartilage and growth plates, where the articular cartilage is thickened. These thickened areas are prone to injury even with normal activity, and can lead to a cartilage flap. The lesions tend to affect both limbs, but can be more severe in one. Rapid growth of young dogs, high calorie diets and/or diets with excess calcium can predispose dogs to this condition. Dogs with OCD typically present between 4 and 9 months old with a mild to moderate weight bearing forelimb lameness. Physical exam shows triceps and biceps muscle atrophy, elbow joint effusion and/or heat, decreased range of motion, crepitus, thickening of the surrounding soft tissue structures, and pain on full extension or flexion of the joint. You can also pick up on OCD lesions by pain exhibited when compressing and grinding the joint. Diagnosis is difficult to make with elbow radiographs. CT or elbow arthroscopy is best and will shows a defect in the bone below the cartilage flap, which is typically on the medial humeral condyle. Treatment is through various surgical procedures to remove the damaged cartilage flap and debride the lesion. Prognosis is better if surgery is performed early.
Sometimes surgery is not a curative option for pets with elbow dysplasia and even more so with pets that have progressed into elbow arthritis. The further progression into the disease the less likely surgery will be curative, but rather palliative. At Walking Paws Rehab we see patients pursue many routes. We rehab patients coming out of surgery. We rehab patients where surgery was not recommended by orthopedic specialists and instead physical therapy recommended. We even rehab patients that pursue regenerative therapies instead. At our first evaluation we can talk to you about the many opt
ions ahead and help guide you on a route that fits your pet’s needs, family, and finances.
Goals of Physical Therapy
Our goals of physical therapy are to reduce and manage elbow joint pain foremost. We focus on reducing compensation in surrounding joints and muscles. Often patients with elbow disease have taut biceps, triceps, lats, teres majors, and reduced range of motion in their shoulder. They compensate in their wrists due to changing forces when weight bearing while trying to off load the inside of their elbow. Often these pets stand with their elbows bowed out, putting excessive weight on the inside of their wrists and medial digits. So they may have some laxity and pain in their wrists. Their elbows are held in a more flexed position leading to the taut biceps. Compensation occurs all the way down to the toes and all the way up the back.
After pain is addressed we then focus on improving flexibility of the muscles surrounding the elbow and compensatory muscles from change in posture and gait. We work on improving range of motion of the joint safely being cautious of any bone chips.
Following improvements in comfort, flexibility, and range of motion we progress into improving weight bearing. Walking in the underwater treadmill is very beneficial for dogs with elbow disease since it allows us to build up muscle while off loading. The elbows don’t have a lot of cartilage and cushion so walking on land can be painful for these patients. Non weight bearing exercises allows us to strength building in a more pain free manner.
Our ultimate goal is to rebuild muscles so whenever your pet takes a step and bears weight through their limb, the muscles are absorbing the shock from the ground and less is going through the bones. Furthermore, improving muscle mass will provide stability to the joint. Maintaining a lean body mass is also important for patients with elbow disease.
If your pet has elbow disease, feel free to reach out to us for any further questions. We can help slow down the onset of arthritis and improve your pet’s quality of life.