Hip Dysplasia

Hip dysplasia (DDH) refers to an “unstable hip”. This means that the hip socket has not fully developed over the femoral head. This may be a congenital abnormality, or it may develop during growth.

A fully developed hip joint can be compared to a soup bowl and a tennis ball. The tennis ball has a little bit of play in the bowl, but not much. Dysplasia can be compared to the tennis ball in a soup plate: this tennis ball has slightly more play in the plate than in the bowl. This means the femoral head is less stable in the socket.

Anterior: A shallow acetabular socket at the front.

Lateral: A shallow acetabular socket at the side.

Anterolateral: A shallow acetabular socket at the front and side.

Posterior (acetabular retroversion): A shallow acetabular socket at the back.

With hip dysplasia, people usually experience pain when:

• Getting in or out of the car
• Strolling
• Walking
• Sitting for extended periods
• Standing for extended periods
• High-impact sports
• …

This is often accompanied by back pain or discomfort.

Why does hip dysplasia cause pain?

Hip dysplasia can be present at birth, but symptoms may only become noticeable later in life as the body adapts and stress increases with age.

Your body is clever and tries to give your hip more stability with the help of the ‘labrum’. This is a ring-shaped structure attached to the rim of the hip socket, similar to a suction cup. The labrum has the following functions:

• Stability: The labrum helps to keep the femoral head securely in the hip socket by forming a kind of ‘cup’.
• Shock absorption: The labrum acts as a shock absorber and helps to absorb forces passing through the hip joint (e.g., during walking).

Due to dysplasia, the labrum has to work 4 to 11 times harder to stabilise the ball. If the labrum can no longer cope with this heavy load, it can tear. This is called a ‘labral tear’. A labral tear can cause the onset of pain and a feeling of instability, or a “clicking hip”, but it doesn’t have to be serious! After all, 54% of people without hip pain have a labral tear on medical imaging.

The muscles are then extra important for stabilising the ball in the socket. The most important muscles for this are the gluteal muscles (buttocks) and the muscles at the front of the hip.

With the right treatment and self-care measures, symptoms can often be well managed, and a good quality of active life can be maintained. Our data shows that 74% of patients do not need surgery thanks to exercise therapy. If symptoms persist, an injection may be given or surgery may be required.

Several surgical options are available for the treatment of hip dysplasia, depending on the degree of dysplasia:

• Peri-acetabular osteotomy
• Arthroscopy (for very mild hip dysplasia or in the presence of a labral tear)
• Total hip arthroplasty (if a severe form of hip osteoarthritis is also present)

We will discuss with you which treatment option is most suitable based on your specific situation and needs.