The Normal Hip Joint
The normal hip is a ball and socket joint. The femoral head (ball) fits perfectly into the acetabulum/pelvis (socket). Both parts are covered by cartilage which allows smooth motion when a dog walks and runs.
What Is Hip Dysplasia
Hip dysplasia is a congenital disease characterized by excessive hip laxity. This laxity results in an imperfect fit between the femoral head and acetabulum. Ultimately, this leads to cartilage wear, bone-on-bone contact, arthritis, and pain.
What Causes Hip Dysplasia
Hip dysplasia is hereditary, especially in certain large breeds including the German Shepherd, Labrador Retriever, Saint Bernard, and Great Dane. Other factors may contribute to clinical signs of hip dysplasia such as rapid growth, excessive exercise, obesity, and improper nutrition.
Symptoms Of Hip Dysplasia
The signs of hip dysplasia are usually apparent in young dogs (5 months to 1 year of age) due to laxity, and then in older dogs when arthritis becomes severe. Most dogs either limp on one or both back legs. They can have difficulty rising, jumping, and using stairs; and they may be reluctant to play. It is common for dogs with hip dysplasia to bunny hop when running.
Diagnosis Of Hip Dysplasia
During a physical exam, dogs are usually painful and have a decreased range of motion in the affected hip. In young dogs before arthritis develops, a sedated exam can be performed which reveals a positive Ortolani sign, or a palpable and audible click when the hip pops back into place. Ultimately the diagnosis is made on x-rays of the hips.
Treatment Of Hip Dysplasia
The treatment of hip dysplasia can vary dramatically based on the age of the patient and severity of clinical signs. In older dogs or those with arthritis, initial treatment is medical in nature. This includes anti-inflammatory medications, pain medications, joint supplements, weight loss, exercise modification, and physical therapy. Most dogs improve with this regimen, but treatment can be life-long.
In dogs that continue to limp and cannot maintain a good quality of life with medical therapy, surgery is indicated to better control pain and discomfort.
Surgery For Hip Dysplasia/Arthritis
Femoral Head and Neck Ostectomy (FHO) - In this procedure, the femoral head (ball portion of the hip joint) is surgically removed, stopping abnormal bone-on-bone contact and relieving pain. Recovery from this procedure is 4-6 weeks and involves aggressive physical therapy to promote early limb use. Outcome is typically excellent for toy and small breed dogs.
Total Hip Replacement- In this procedure, the entire hip joint is replaced with size fitted metal implants. Total hip replacement is the only procedure to provide an anatomically normal joint. Recovery from this procedure is 8-12 weeks and involves initial strict rest followed by controlled formal rehabilitation. This is the procedure of choice in large and giant breed dogs.