Hip dysplasia is one of the most common hip conditions. Hip dysplasia is literally an abnormal development of the hip joint. Hip laxity begins as early as 4 months of age. The amount of hip laxity, and the chances of developing hip arthritis, can be determined using a special radiographic technique called PennHip. As dogs get older, secondary osteoarthritis becomes apparent. In the most severe cases, the hip can actually dislocate because the laxity and remodeling changes are so severe.
Owners frequently recognize the following signs and symptoms in dogs with "hip dysplasia"
Puppies seem to be "laid back" and not as active as other puppies (likely because they hurt)
Older dogs may be described by their owner as "slowing down"
Not sitting squarely (sit on one side of the pelvis)
Difficulty rising, stiff gait during the first few steps are getting up
Difficulty going up stairs, unwilling to jump up onto furniture or into cars (any activity involving hip extension is painful)
Bunny hopping gait (pushing off with both hind limbs simultaneously to reduce powerful hip extension in each limb -- it's less painful pushing off with both)
Personality changes -- may seem "grumpy"
Difficulty sleeping, trouble getting comfortable
Obvious lameness/limping -- this seems obvious, but because dogs are usually affected with hip dysplasia in both hips, an asymmetric gait may not be apparent unless one hip is substantially worse than the other
Treatment should begin as early as possible. Surgical and medical treatments are used to help reduce the pain and lameness of hip dysplasia.
4-5 months of age → Juvenile Pubic Symphysiodesis (JPS)
5-12 months of age → Triple Pelvic Osteotomy (TPO), Double Pelvic Osteotomy (DPO)
10+ months of age → Femoral Head and Neck Ostectomy (FHO), Total Hip Replacement (THR)
See section on Arthritis Management
For more information, see the Dog Owner's Guide to Hip Dysplasia
The radiographs on the left are from a dog with severe hip dysplasia, with much laxity of the hip. The dog on the right has more laxity in one hip than the other.
These radiographs are from a dog that has undergone a total hip replacement.
Legg-Calve-Perthes, sometimes called aseptic necrosis of the femoral head, is a condition found in small breeds of dogs. There may be a heritable component to the condition. Essentially, there appears to be compromised blood supply to the femoral head (ball part of the hip joint), which results in resorption of bone, and subsequent collapse and remodeling of the femoral head and neck. The condition occurs in skeletally immature dogs, between 5 and 10 months of age. It may affect both hips.
Dogs generally have severe lameness, even non-weight bearing lameness. There is pain with hip manipulation, especially hip extension. Radiographs confirm the diagnosis, with demineralization of the femoral head and neck, remodeling of those structures, and sometimes evidence of collapse of the femoral head.
Surgery is necessary to treat the condition. Most cases are treated with a femoral head and neck ostectomy to allow a false joint to form. Postoperative pain control to allow effective physical rehabilitation is critical to successful return to function. Another option is a total hip replacement, although most small dogs do well with a femoral head and neck ostectomy.
This dog has Legg-Calve-Perthes disease, indicated by the arrow. There is decreased bone density, and the femoral head and neck are beginning to collapse.
This dog has had a femoral head and neck osteotomy performed. This surgery was performed for Legg-Calve-Perthes, but could also be performed for end stage hip dysplasia.