Veterinary Services


PennHIP/OFA in Cary, NC

OFA and PennHIP

One way of achieving the goal of trying to reduce the risk of hip dysplasia is to have an accurate test for susceptibility to this disease.

Orthopedic Foundation for Animals (OFA)

The Orthopedic Foundation for Animals (OFA) hip joint scoring system uses a method of evaluating the hip joint using one radiograph that shows the extended view of the pelvis. A preliminary evaluation can be attained before 24 months of age or a permanent evaluation on or after 24 months of age.

This system rates a dog’s hip joint on a seven-point scoring system. The test relies on the interpretation of a radiograph of the hips, which is then assigned a score by three independent radiologists: Excellent, Good, Fair, Borderline, Mild, Moderate, and Severe.

University of Pennsylvania Hip Improvement Program (PennHIP)

The University of Pennsylvania Hip Improvement Program (PennHIP) involves evaluating the canine hip both qualitatively and quantitatively. The qualitative aspect involves assessing the hip joint conformation and any evidence of dysplastic changes, and the quantitative aspect involves measuring the joint itself for laxity. The PennHIP method can be performed on animals as young as 16 weeks of age.

PennHIP requires the dog to be anesthetized. Three radiographs are taken to measure the hip joint laxity. A score between 0-1 is assigned, with 0 being very tight hips and 1 being very loose. The test is not pass-fail, and the score is actually based on a measurement of the hip’s distraction index (DI).

The DI is an indication of the ‘percent out of joint’ that the femoral head is displaced from the acetabulum. The index is measured using circular gauges that are placed over the films, and the final number reflects factors such as the size of the dog and how it compares to the rest of the population. This method generally defines a DI of ≥0.30 as “osteoarthritis-susceptible”, and a DI of ≤0.30 as “osteoarthritis-non-susceptible.”

Program Components

The main components of both programs are using x-rays to examine the hips, procedures performed by trained Veterinarians, and a database containing the information. The goal is to reduce the occurrence and severity of hip dysplasia. Some breeders only use and believe in one of the two techniques, PennHIP or OFA, and use that technique exclusively. Very few breeders screen all breeding stock using both techniques.

Owners must complete the online paperwork directly with the chosen evaluation certification. Select the link below to be linked to the organization where you will locate the evaluation form.

The paperwork must be brought with you to your appointment with us.

DO NOT FORGET TO COMPLETE THE CREDIT CARD INFORMATION ON THE FORMS. We will complete our portion of the form and send it directly to the organization you have selected.