-Hip Dysplasia (HD)-

Hip dysplasia, or HD for short, is a developmental malformation of the hip joint and is one of the most common musculoskeletal disorders in dogs — although English Cocker Spaniels are less frequently affected compared to larger breeds.
It is a hereditary deformation: the femoral head (the “ball”) does not fit properly into the hip socket (the “joint”), which can lead to joint instability, pain, and limited mobility.
The predisposition is genetic and present from birth, but symptoms typically manifest during skeletal development. Environmental factors such as improper nutrition, rapid growth, overweight, or incorrect strain during puppyhood can also accelerate the progression.
A definitive diagnosis is usually only possible after growth has completed — typically between 12 and 18 months of age. The most important diagnostic tool remains the X-ray, which is mandatory for dogs intended for breeding.

HD Severity Grades in Dogs (according to FCI guidelines)
Hip dysplasia (HD) is classified into five severity grades. The assessment is primarily based on the Norberg angle measured on the X-ray — which describes how well the femoral head fits into the hip socket.
Below is an overview of the HD grades with explanations:

🅰️ Joints unremarkable in every respect.
✔️ Norberg angle of 105° or more.
💬 In cases of an exceptionally good fit, this is also called A1, when the acetabular rim covers the femoral head particularly well.
🔢 Approximately 25% of dogs achieve this ideal rating.

🅱️ HD-B – Borderline
👉 Very slight irregularities on the femoral head or acetabular roof.
✔️ Norberg angle of 105° or more, but with slight uneven shape
or
✔️ Norberg angle below 105°, but with even shape of the femoral head and acetabulum.
🔢 About 33% of dogs show this form.

🅲  HD-C Mild Hip Dysplasia

👉Noticeable irregularities of the joint surfaces.
✔️ Norberg angle 100° or less
✔️ Possible early signs of arthritis.
🔢 About 27% of dogs have mild HD.

🅳  HD-D – Moderate Hip Dysplasia

👉 More pronounced malformations, possibly partial dislocations (subluxations).
✔️ Norberg angle above 90°, but clearly abnormal joint
✔️ Significant arthritic changes and/or flattening of the acetabular rim.
🔢 About 11% of dogs show this grade.

🅴  HD-E – Severe Hip Dysplasia
👉 Severely deformed hip joints, poor fit.
✔️ Norberg angle below 90°
✔️ Marked flattening of the acetabulum, severe arthritis, susceptibility to pain.
🔢 About 4% of dogs are severely affected.

Breeding regulations of the Spaniel Club Germany
In Germany, English Cocker Spaniels may only be used for breeding if they have hip dysplasia grades A, B, or C.
A dog with grade C may only be mated with a partner with grade A to minimize the risk for the offspring and to promote the long-term health of the breed.