There is no single best treatment for CHD. Treatment recommendations will depend on the dog’s age, body weight/size, degree of discomfort/dysfunction, examination, and X-ray findings, your expectations for your dog and your budget. Additionally, not every pet diagnosed with CHD requires treatment. Approximately 75% of young dogs with CHD can maintain acceptable function well into maturity without developing significant symptoms of hip pain. Medical and surgical options are available for young and mature pets with CHD. Most dogs are initially treated with medical management.
Medical treatment entails a combination of multiple modalities to improve your pet’s comfort as much as possible without surgical intervention and includes the use of aggressive weight loss/management, consistent exposure to lower-impact activities (walking, swimming etc.), nonsteroidal anti-inflammatory drugs, physical rehabilitation, fish oil supplements, and disease modifying osteoarthritis drugs. Dogs in Group 1 (see Signs and Symptoms) generally do not respond as well to medical treatment as do dogs in Group 2 (see Signs and Symptoms). For this reason, earlier surgical intervention with procedures such as juvenile pubic symphysiodesis (JPS) or pelvic osteotomy may be indicated.
JPS is a technique for stopping the growth of the pubis (part of the pelvis) to alter the growth/shape of the pelvis, while increasing the ball’s degree of coverage by the socket to diminish hip laxity. It is a relatively minor surgical procedure and puppies less than 18 weeks of age must have it performed. However, since most puppies of this age do not show symptoms of CHD, early diagnosis by way of examination and special X-ray techniques is critical.
Another option for immature dogs (ideally less than 10 months old) with CHD but no arthritic changes is a double or triple pelvic osteotomy (DPO/TPO) surgery. These procedures involve cutting the pelvic bone in two (DPO) to three places (TPO) and rotating the segments to improve coverage of the ball by the socket and decrease hip laxity (Figure 4). The TPO has been used in dogs for decades. Recent advancements in implant (locking plates and screws) technology now allow similar results with only two cuts made in the bone.
Immature dogs with evidence of hip arthritis are not ideal candidates for TPO/DPO, nor are dogs with very severe hip laxity. Dogs need to be screened by examination and X-rays to determine if they may benefit from these procedures. Manage non-candidates medically until they are mature enough for total hip replacement (THR) or femoral head ostectomy (FHO) surgeries.
Young dogs not meeting the criteria for TPO/DPO or JPS procedures, or Group 2 dogs who do not respond satisfactorily to medical treatment alone may benefit from FHO. This technique involves removing the femoral portion of the hip joint (i.e., the ball) in order to reduce the pain produced by abnormal hip joint contact and the stretching of the soft tissues around the joint due to laxity (Figure 5). Following an FHO, a “false joint” develops with the muscles around the hip now transferring the forces from the leg to the pelvis during limb movement. The goal of an FHO is to relieve the pain associated with CHD, not to maintain/recreate normal hip function. This latter fact is why FHO is generally considered less desirable in larger dogs.
THR is another option for Group 1 and 2 dogs. This procedure eliminates hip pain and, unlike an FHO, reproduces the mechanics of a normal hip joint producing, more natural range of motion and limb function. As with humans, canine THR involves replacement of both the ball and socket with metal and polyethylene (plastic) implants (Figure 6). These components are fixated in place with bone cement, metal pegs, or “press fit” (bone ingrowth) methods.
Previously, triple pelvic osteotomy (TPO) had been performed in selected young dogs with hip dysplasia to reorient the acetabulum (socket) over the femoral head (ball). The procedure was fairly successful but morbidity (postoperative complication and discomfort) was high compared to other routine orthopedic procedures. Because of this, the procedure has been modified to a double pelvic osteotomy. Double pelvic osteotomy involves making two osteotomies (bone cuts) in the pelvic bones, reorienting the acetabulum over the femoral head and securing the osteotomy with a bone plate. Because a portion of the pelvis is left intact with the DPO, postoperative discomfort and complication have been minimized.
Numerous factors are considered when deciding which patients will benefit from a DPO. Patient selection criteria must be adhered to for outcomes that are consistently good to excellent. Potential patients should be less than eight months of age, have no osteoarthritis, the femoral head should be normal in size and shape and the femoral head should fall into place within the acetabulum on palpation without excessive force or angulations.