The hip assumes a vital role in supporting upper body weight during standing, walking, and running, emphasizing the importance of hip stability. The hip joint is formed by the femur (thigh bone) and acetabulum (hip bone), while stability is upheld by the labrum (tissue rim sealing the hip joint) and ligaments lining the hip capsule. Damage or injury to these structures can precipitate hip instability, characterized by various symptoms.
Symptoms
Common indicators of hip instability encompass:
- Pain
- Laxity
- Hip giving way
- Clicking sensation
- Dislocation
Causes
Hip instability may arise from traumatic or atraumatic origins. Traumatic instability stems from sports injuries or motor vehicle accidents, which can harm bony structures, labrum, and cartilage of the hip joint, sometimes resulting in loose bodies. It ranges from severe dislocation to partial hip joint displacement (subluxation). Atraumatic instability may stem from overuse or developmental/congenital hip abnormalities.
Conditions contributing to hip instability include:
- Labral and ligament tears
- Hip dysplasia (misaligned hip joint bones)
- Femoroacetabular impingement (abnormally shaped hip joint bones)
- Ligamentum teres tears
Treatment
Initial treatment may involve conservative/non-operative measures like protected weight bearing (e.g., crutches, cane, wheelchair) and referral to a physical therapist for tailored exercises aimed at enhancing strength, balance, and flexibility.
If conservative methods fail to alleviate symptoms or in the presence of significant fractures, surgical intervention may be recommended. Surgery can be arthroscopic (minimally invasive) or open, depending on the severity. Common causes of hip instability, including damage to the hip capsule, ligaments, and labrum, can often be addressed arthroscopically. Your doctor will guide you through the best course of action to address your concerns and mitigate instability.
Diagnosis
Diagnosis of hip instability relies on medical history, physical examination, and imaging studies such as plain X-rays, MRI, and MRI arthrography (utilizing contrast agent) to confirm instability. Hip instability tests, such as posterior impingement or dial test involving range of motion exercises, may also be conducted.