What is Borderline Hip Dysplasia?
Hip dysplasia is a medical condition where the acetabulum (hip socket) does not fully cover the ball-like head at the top of the femur (thighbone). Most people who have hip dysplasia are born with it.
Borderline hip dysplasia is a mild form of hip dysplasia that is typically found in young adults.
Overview of Borderline Hip Dysplasia
Your hip is a ball-and-socket joint where the ball of your thigh bone (femoral head) fully fits into the socket of the hip bone (pelvis) to form the hip joint. At birth, your hip joint is made of soft cartilage that later hardens into bone. Over time, the ball and socket help mold each other so that they develop an appropriate fit together.
At times, the ball of the hip joint may slightly move out of position when the space within the womb becomes constrained shortly before birth. In such cases, the socket may not form correctly and can end up being shallow as the child grows. This results in the socket not fully covering the ball leading to borderline hip dysplasia.
Significance of the Condition
Your hip is very important as it supports much of your body’s weight and allows you to move your upper legs so you can walk, climb stairs, and even sit. If your hips are normal, the ball can rotate freely in the socket to let you move.
With dysplasia, the socket does not fully cover the ball causing the hip joint to wear out faster than normal or easily dislocate. That is why a condition like hip dysplasia can have a big impact on your life.
Borderline hip dysplasia is mostly congenital and tends to run in families. It is common among teenagers, more so in girls. However, the risk of borderline hip dysplasia can be higher if you are born:
- In the breech position (bottom or feet-first position)
- With foot deformities (structural abnormalities)
Complications of Borderline Hip Dysplasia
- Partial dislocation of the hip joint
- Damage of soft cartilage rimming the socket
- Degeneration of cartilage (osteoarthritis) after middle age
Symptoms of borderline hip dysplasia can be any of the following.
- Pain during hip movement
- Reduced hip stability
- Marginal limping while walking
- Osteoarthritis or a hip labral tear
- Pain in the groin, lateral hip and buttock
- Unstable sensation in the hip
- Possibility of hip arthritis later in life
- Clicking and catching during physical activities
Borderline hip dysplasia can be difficult to diagnose as it might not cause problems until the teenage years. The diagnosis can include any or all of the following:
- Thorough physical examination and radiographic evaluation
- Imaging tests such as X-rays, ultrasound, or MRI
- Clinical examination of the hip followed by impingement tests
- Neurovascular examination to check for signs of joint laxity
Treatment of borderline hip dysplasia depends on the stability of your hip joint. In a stable hip joint, it can be treated both non-surgically and surgically.
- Physical therapy involving strengthening the muscles around the hip joint
- Patient education, activity modification or administration of simple analgesics (pain-relievers)
- Use of non-steroidal anti-inflammatory drugs (NSAIDs) or intra-articular injections
- Hip arthroscopy or surgical hip dislocation
- Osteotomy or periacetabular osteotomy (PAO)
If the dysplasia causes hip joint instability, your doctor may consider any of the following:
- Reorientation osteotomy with PAO
- Femoral osteotomy
- Acetabular reorientation (most common)
Regardless of procedure, the treatment is typically aimed at:
- Correcting the abnormal shape of the hip joint
- Reducing the pain related to borderline hip dysplasia
- Mitigating the risk of developing early arthritis