Hips

The hip joint

Hip dysplasia

Hip dysplasia (HD) is a common condition of dogs and also occurs occasionally in cats, particularly the larger pedigree cats. Hip dysplasia is abnormal development of the hip during the first few months of life. This starts with excessive laxity of the joint which leads to instability between the ball of the joint (the femoral head) and the socket (the acetabulum). That instability leads to secondary remodelling of the developing femoral head and acetabulum such that the femoral head becomes flattened and the acetabulum becomes shallow resulting in a poorly fitting joint. This poor fit eventually leads to secondary osteoarthritis. There are many dogs that have a degree of HD which is tolerated and does not cause clinical signs but some dogs are not so lucky and have pain associated with the dysplasia when they are young (typically 6-12 months of age). Probably more dogs end up with pain from secondary osteoarthritis even though they did not have obvious pain when they were young.

So, broadly speaking there are two categories of dogs that present with hip pain associated with HD:

• Young dogs with pain from dysplasia
• Middle-aged to older dogs with secondary osteoarthritis

Management of hip dysplasia and secondary osteoarthritis also falls in to two categories:

Medical and supportive management

• Medication for pain relief (see our osteoarthritis information sheet)
  
• Support through weight control, environmental adaptations, exercise control, physiotherapy (see our osteoarthritis information sheet)

Surgical management

Total Hip Replacement

• This is the treatment of choice for the intractably painful hip that has not responded sufficiently to medical management. The most common age for a dog to have a hip replacement is 1-2 years of age and this is usually because the pain from dysplasia is such that it cannot be controlled with medical management. The hip replacement should last for the lifetime of the dog.
  
• Total hip replacement can be performed on almost any size of dog. It is generally a very successful procedure but complications can occur and so it is essential that clients are carefully counselled by an experienced surgeon so that they can understand the likely benefits but also the potential risks associated with the procedure.

At Movement Vets, all our orthopaedics surgeons are experienced in total hip replacement. We contribute to the British Veterinary Orthopaedic Association’s Canine Hip Registry. We contribute to the British Veterinary Orthopaedic Association’s Canine Hip Registry. The registry is a database of thousands of canine hip replacements and follows the long-term outcome of such operations so that vets can better understand the benefits and risks of the operation. The registry was founded by Movement Referrals Director, Professor John Innes.

Excision arthroplasty

Sometimes, when there is severe disease of the hip and a joint replacement is not possible, the femoral head and neck are removed in a procedure called an excision arthroplasty. Dogs can function quite well without a hip joint due to the muscular support around the hip.