WORKING THE AFFECTED DOG
Often, the dog that is diagnosed with mild ED of one sort or another belongs to someone active in the sport end of the dog game, having no plans to breed but wanting to do obedience or schutzhund work. Caution must be advised here, but it is possible for many dogs to live a happy life and compete in such events. Schutzhund is more demanding, as the dog has to clear a one-meter-high jump, run fast, and struggle with a “bad guy”, all of which can put sufficient stress on mildly dysplastic elbows as to cause trauma. AKC-CKC-type obedience is easier, as the jump heights have been lowered, the rings are small, and no really fast running for considerable distances is required. The retrieves are to be performed briskly, but that is nothing compared with the work demanded in schutzhund. Let your dog and your common sense guide you in how much you ask or encourage your dog to do. These dogs especially should be prevented from becoming heavy. Many of the Grade 1 dogs will not develop any lameness. As is recommended for any other sort of osteochondrosis, keep the nutritional volume and energy level (and hence the weight) down, and do not supplement with calcium. DeBoer recommends a diet with less than 17% fat, and lower than 4 kilocalories per gram energy density.
TREATMENT OF UAP
Even as late as the early 1980s, controversial forms of treatment were being promoted and practiced. Some advised rest, painkillers, and patience; others were experimenting with fixation with wires, screws, and the like; a fourth type of treatment proposed was surgical fusion of the elbow. All these have fallen out of favor as a result of comparisons, and removal of the offending particles is now generally agreed upon as the only reasonable treatment.
Upon diagnosis of UAP, the patient should be scheduled for surgery to remove the “loose” piece. While it might not be bouncing around like a ping-pong ball, there is enough movement in relation to other structures in the joint to cause irritation and promote worsening degenerative changes. If not diagnosed until gross changes in appearance and gait have become obvious, there may only be a 50/50 chance of improvement in gait and the rate of osteoarthritis development. Early correction is far better, and routine radiography of your young stock is cost-effective in the long run, as well as beneficial to your breed and your public image. In past years, attempts were made to screw the ununited piece onto the ulna, but for the most part, these were very disappointing. As late as 1989, some few practitioners in Australia were still advocating it as a treatment for 6- to 10-month old dogs. No matter what surgical or other treatment is chosen, joint incongruity is not improved.
Olsson’s work referred to in the 1990 Proceedings of veterinary meetings regarding orthopedics, trauma, and surgery also carried a reference to a new surgical technique he called “high osteotomy of the ulna”. While he didn’t elaborate on the procedure, it appeared that there was the idea of some promise to creating bony union between the ossifying anconeal process and the ulna by relieving the pressure and surgically replacing the cartilage and allowing callus or bone to grow in the gap. Wind attributes it mostly to the decrease in space and movement.
Here is what Olsson said about treatment as early as the mid-1970s: The most common procedure is to remove the ununited process via a lateral incision between the lateral epicondyle and the olecranon. There seems to be a time factor to consider when one decides to do surgery. It is the experience of the present author that surgery should not be done until the dog has reached an age of 9-12 months. If it is done earlier, during the period of very fast growth (four to eight months), secondary changes (remodeling and osteoarthrosis) seem more likely to develop after surgery than if the ununited anconeal process is left in place until a time when growth is almost completed.
TREATMENT OF FCP
In cases of FCP and OCD of the medial condyle of the humerus, surgery preferably should be done as soon as diagnosis is made. Only the medial approach to the elbow joint can be used. In early cases of OCD of the medial condyle of the humerus there is a defect in the weight-bearing surface, covered by a flap of cartilage. The flap should be removed and the edges trimmed. In later cases there is usually no flap. Instead it may have been turned into a large cartilaginous body that may be found adhering to the joint capsule. It may even have been resorbed. In a joint with only a defect and no flap, only the edges of the defect should be trimmed. Whatever the findings, the coronoid process should be carefully inspected, as OCD of the medial condyle is frequently combined with FCP.
The most common finding in FCP is an elongated, cartilage-covered ossicle, which lies between the coronoid process and the head of the radius. Sometimes the coronoid process is fragmented in several small pieces. On the opposing joint surface there always is considerable erosion caused by the loose fragments. All fragments should be removed. After surgery the dog is caged for about 10 days and kept on restricted exercise for a period of four to six weeks. If the only finding at early surgery is FCP and the fragments can be completely removed, prognosis is good. If surgery is done late (after the appearance of large osteophytes), prognosis is guarded. The joint usually will become pain-free but range of motion will remain limited. In cases of OCD of the humeral condyle or in cases with combination of these two lesions, prognosis is always guarded even if surgery is done early. However, surgery should always be tried, as an untreated case of either of the two lesions or a case with the two lesions combined usually develops into a case of very severe osteoarthrosis. It should be remembered, however, that in many dogs with FCP the lesion can remain undetected for years. This usually happens in dogs with bilateral lesions and with owners who are not very observant. These dogs often are first brought to a veterinarian when there is acute lameness due to trauma to one of the severely osteoarthrotic elbow joints.
Olsson also has said, “…early removal of loose cartilage and ossicles, although not a panacea, seems to be the only rational treatment of FCP and OCD.” Since early removal is needed, the veterinarian must become familiar with the signs and diagnosis of each as well as follow the procedures in his surgery textbooks. By the early 1980s surgical techniques were developed which will be sufficient today. Sometimes the fragment from the coronoid process becomes attached to the corresponding part of the medial humeral condyle, other times it lodges in the joint between the radius and ulna. Dr. Flo of Michigan State has reported on a 10-year old Lab with little or no DJD but with fragments of the coronoid. Apparently there was no earlier diagnosis; in fact, radiographs at a much younger age revealed normal anconeal process and no DJD or osteophytes. But here was this old dog who was slowing down because of pain, even though the owner for a while thought it was “just age”. Arthrotomy revealed the loose coronoid fragments, and indicated that some were “in the way” of articulation so much that they actually caused pieces of the anconeal process to fracture and contribute more bone fragments to the joint, with more inflammation a natural consequence. After removal of the pieces, the dog’s attitude and activity dramatically and immediately increased and lameness improved. It was deduced that this dog had semi-healed or stable coronoid fissures for a long time, but that continued use of the limbs over those ten years of high activity finally loosened those fragments, allowing them to move around in the joints.
In some minor cases, only cartilage damage rather than coronoid fragmentation may exist, and in others, the fragment may reunite and the process heal. Perhaps this is because the lagging growth rate of the ulna’s trochlear notch catches up with the growth of the humeral trochlea enough to recreate the greater measure of congruity, if indeed it does. If the lag is very temporary, not enough incongruity may appear on the radiograph although the lesion is seen upon necropsy.
Another technique, based on the differential growth rate theory, is the transverse (“horizontal”) slicing of the ulna with a saw, making it shorter than before, and giving the humerus the broad head of the radius to sit on as it is designed to do. At least one writer claims that this operation also has some sort of effect on the anconeal process, “allowing” it to unite.
TREATMENT OF ELBOW OCD
As in FCP, the only good way to handle OCD of the humeral condyle is by going in and removing the culprit responsible for the damage, and before much of that damage has been done. I can’t emphasize the word “early” enough, especially in OCD, since in this lesion, delay gives a worse prognosis than it does in the other two elbow dysplasias. Get the minor cases treated early enough, and you might slow the progression of arthritis and overcome lameness. If the flap hasn’t come loose yet, the results are best, and the size of the flap or mouse has a bearing on it, too. One approach is to saw through the epicondyle so the muscles and tendons attached to it can be pulled out of the way while the area of the fragment(s) can be scraped and washed out. The epicondyle is put back and held in place with a lag screw, and the joint closed.
Prognosis for surgical improvement of either FCP or OCD of the humerus is usually “guarded”, with about 50% of those operated on being relieved from lameness. The extent of degenerative change may have much to play in this scene, although some arthritis develops whether or not surgery is performed. Many of those who do not limp may simply not favor one bad elbow over the other, and decreased mobility of the joint is hard to objectively assess, as is the case with FCP.