Hip Dysplasia is the abnormal development of the coxofermoral (hip) joint. It is usually luxation (dislocation) or sublaxation of the fermoral head in younger dogs and mild to severe Dejenerative Joint Disease in older dogs.
The causes of hip dysplasia seem to be varied, from genetics, environmental and nutritional factors all being involved. Genetics is believed to have the most impact, however, rapid weight gain and growth when younger combined with poor nutrition also play a role. Recent studies are also linking sterilsation due to the impact on the hormonal system and growth development.
Clinical signs of hip dysplasia include:
- exercise intolerance
- muscle wastage (atrophy) in pelvic muslces
- waddling gait
- difficulty rising after rest/sleep
- lameness (continuous or intermittent) increased severity after exercise or possible injury
X-rays are normally taken in dogs around the age of 12months to identify hip dysplasia and provide hip scores for breeders.
If your dog has hip dysplasia and depending on the severity you can look at conservative therapies such as hydrotherapy, massage, kinesiology, acupuncture and herbal remedies. If surgery is required the most common surgical procedures include:
- Triple Pelvic Osteotomy. This stabilises the hip and reduces progression of degenerative joint disease. Involves 3 cuts to the pelvic bones and screwing in position using a special plate. Usually for younger dogs and not all that common today as more improved surgeries have emerged.
- Total Hip Replacement. This is very expensive and dogs must be skeletally mature, older than 10 months. A polyethylene acetabular cup and metal (cobalt chrome) femoral head and neck are used to replace the existing joint.
- Femoral Head Osteotomy. The femoral head and neck are removed and the scar tissue is eventually replaced by a new fibrous joint. Usually for dogs and cats under 20kg.
- DARthroplasty. A bone graft is used to extend the DAR (dorsal acetabular rim) and sutured to the adjancent joint capsule. Provides support through joint capsule fusion rather than bony fusion.