Hip Dysplasia
Explanation of Diagnosis of Hip Dysplasia
The hip is a ball-and-socket joint lined with cartilage. The socket, called the acetabulum, is typically deep and provides stability to the round femoral head. In hip dysplasia, the acetabulum is abnormally shallow, and the natural stability of the joint is reduced. This leads to increased joint stress—known as “edge loading”—along the rim of the acetabulum, which can cause labral and cartilage damage over time.
How did I get Hip Dysplasia?
Hip dysplasia can arise from a combination of genetic, developmental, and environmental factors.
Genetic factors: Hip dysplasia can run in families. It is more common in females, particularly those who are first-born and born breech. These risk factors are thought to relate to the natural joint laxity seen in females and the abnormal mechanical forces experienced during breech delivery.
Environmental and activity-related factors: Certain activities that involve extreme hip motion—such as dance or gymnastics—can contribute to the development of hip dysplasia. During growth, repetitive movements into extreme ranges (e.g., the splits) may prevent the acetabulum from forming a deep, stable shape.
Variation in severity: Hip dysplasia can range from very mild (slightly shallow acetabulum) to severe forms that cause significant instability and pain. Interestingly, a shallow hip socket may confer a flexibility advantage in some athletes, though it predisposes them to joint degeneration later in life.
How is Hip Dysplasia Diagnosed?
Diagnosis begins with a detailed history and physical examination. The most common symptom is groin pain that worsens with activity or prolonged standing. Patients often compensate by walking with a limp. Pain may radiate to the inner knee or outer hip. Many patients with hip dysplasia have greater-than-normal hip mobility (hypermobility) and may also display joint laxity in other parts of the body.
If hip dysplasia is suspected, X-rays are obtained to evaluate the shape of the acetabulum and femur. A CT scan may be ordered to further define the bony anatomy, while an MRI can assess the integrity of the labrum, cartilage, and capsule.
A diagnostic hip injection with local anesthetic (numbing medicine) may also be performed to confirm the hip as the true source of pain. Relief following the injection supports the diagnosis of intra-articular hip pathology.
What are the Indications for Nonsurgical Treatment?
Initial treatment focuses on conservative management, including:
Activity modification to reduce aggravating movements.
Physiotherapy to strengthen the hip and core muscles, improving stability and reducing symptoms.
Anti-inflammatory medications to control pain and inflammation.
Not all cases of hip dysplasia require surgery. Many individuals with mild dysplasia can remain symptom-free or manage well with targeted rehabilitation and strength training.
What are the Indications for Surgical Treatment?
Surgery is recommended for patients with symptomatic hip dysplasia who do not respond to conservative treatment. Surgical options depend on the severity of dysplasia and the condition of the joint:
Hip Arthroscopy: Performed through small incisions using a camera and instruments to repair labral tears, smooth cartilage damage, and tighten the hip capsule to improve stability. This is generally reserved for mild cases of dysplasia.
Periacetabular Osteotomy (PAO): A joint-preserving procedure that involves cutting and repositioning the acetabulum to improve femoral head coverage and stability. In some cases, the femur may also be reoriented to optimize joint alignment. These surgeries are best suited for younger patients with minimal cartilage wear.
Total Hip Replacement: Recommended for end-stage arthritis resulting from longstanding dysplasia. This option is most appropriate for older or lower-demand patients where joint preservation is no longer feasible.
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