In 1996, John M. Olin founded the Orthopedic Foundation for Animals (OFA) as a private not-for-profit foundation to evaluate and determine if a dog will have problem hips. Canine Hip Dysplasia is a genetic condition that primarily affects larger breeds but can be diagnosed in a few smaller breeds as well. Hip dysplasia typically develops because of an abnormally developed hip joint but can also be caused by cartilage damage from a traumatic fracture. Cartilage damage or an abnormal hip joint, over time will lose its thickness and elasticity of the existing cartilage. This will eventually result in pain with any joint movement. Radiographs taken by a licensed veterinarian (DVM) is the only way to diagnose hip dysplasia or certify the hips free of any problems. OFA maintains a database for hip dysplasia and is classified into seven different categories:
- Excellent: Superior conformation; there is a deep-seated ball (femoral head) that fits tightly into a well-formed socket (acetabulum) with minimal joint space.
- Good: Slightly less than superior but a well-formed congruent hip joint is visualized. The ball fits well into the socket and good coverage is present.
- Fair: Minor irregularities; the hip joint is wider than a good hip. The ball slips slightly out of the socket. The socket may also appear slightly shallow.
- Borderline: Not clear. Usually, more incongruency present than what occurs in a fair but there are no arthritic changes present that definitively diagnose the hip joint being dysplastic.
- Mild: Significant subluxation present where the ball is partially out of the socket causing an increased joint space. The socket is usually shallow only partially covering the ball.
- Moderate: The ball is barely seated into a shallow socket. There are secondary arthritic bone changes usually along the femoral neck and head (remodeling), acetabular rim changes (osteophytes or bone spurs) and various degrees of trabecular bone pattern changes(sclerosis).
- Severe: Marked evidence that hip dysplasia exists. The ball is partly or completely out of a shallow socket. Significant arthritic bone changes along the femoral neck and head and acetabular rim changes.
The hip grades of excellent, good, and fair are within normal limits and are given OFA certification numbers. This information is accepted by AKC on dogs with permanent identification and is in the public domain. Dog showing signs of hip dysplasia are often treated with anti-inflammatory pain relievers, while some require surgical correction. OFA hip certification is conducted on dogs 2 years of age and older but preliminary evaluations are available for dogs over 4 months old.