What is Snapping Hip Syndrome?

Snapping Hip Syndrome: Definition, Classification, and Management

Snapping hip syndrome (coxa saltans) is a condition characterized by an audible or palpable snap that occurs around the hip during movement, which may be accompanied by pain and is commonly seen in athletes requiring increased hip range of motion.

Classification

Snapping hip syndrome can be classified into two main categories:

1. Extra-articular Snapping Hip

• Further subdivided into:
  • External snapping hip: Caused by the iliotibial band snapping over the greater trochanter 1, 2
  • Internal snapping hip: Attributed to an abrupt movement of the iliopsoas tendon against the iliopectineal eminence 3, 2

2. Intra-articular Snapping Hip

• Caused by loose bodies, labral tears, or other intra-articular pathologies 1, 4

Epidemiology

• Estimated to occur in up to 10% of the general population 1
• More common in athletes such as dancers, soccer players, weight lifters, and runners 1, 2
• Painless snapping is common in the general population, while symptomatic snapping with debilitating pain is often seen in activities requiring extreme hip movements 5

Clinical Presentation

• Audible or palpable snap during hip movement 1, 3
• May be accompanied by pain or locking 3
• May follow physical trauma, intramuscular injections, or surgeries 3
• For internal snapping hip, the snap is typically elicited by specific movements requiring contraction of hip flexors 2

Diagnostic Approach

Initial Imaging

• Radiographs: Should be obtained first in most cases, though results tend to be normal in extra-articular snapping hip 6
  • View of the pelvis and additional image of the proximal femur is better than radiographs limited to the ipsilateral hip 6

Advanced Imaging

• Dynamic ultrasound: Gold standard for diagnosing extra-articular snapping hip syndrome 3

  • Allows real-time visualization of the abnormal tendon friction during hip movement 3
  • Particularly useful for evaluating snapping iliopsoas tendon 6
  • Patient performs specific provocation tests during examination to reproduce the snap 3

• MRI: Useful after initial radiographs to detect osseous and soft tissue abnormalities 6

  • Can show secondary signs that may suggest snapping hip syndrome 6
  • Helps evaluate surrounding soft tissue entities that may contribute to symptoms 6

Management

Conservative Treatment

• Most patients with snapping hip can be treated conservatively 5, 2
• Treatment includes:
  • Anti-inflammatory medications 2
  • Stretching exercises 2
  • Avoidance of inciting activities 2
  • Diagnostic and therapeutic injections may be useful for determining the cause of hip pain and providing short-term relief 6

Surgical Treatment

• Indicated when the condition becomes chronically symptomatic and fails to respond to conservative management 4, 5

• Surgical options include:

  • For external snapping: Endoscopic release of the ilio-tibial band or the femoral insertion of the gluteus maximus tendon 4
  • For internal snapping: Lengthening of the iliopsoas tendon 2
  • For intra-articular causes: Arthroscopy to address intra-articular lesions 5

• Endoscopic techniques provide fewer complications compared to open surgery, lower recurrence rates, and good clinical outcomes 4

Clinical Pearls and Pitfalls

• Snapping hip syndrome must be differentiated from other causes of hip pain such as femoroacetabular impingement, acetabular dysplasia, and labral tears 6
• Internal snapping hip may be difficult to distinguish from intra-articular causes of snapping 2
• Radiographs may be normal in patients with extra-articular snapping hip, necessitating dynamic imaging studies 3
• Diagnostic injections can help confirm the location of pain and assist in treatment planning 6
• When evaluating snapping hip, it's important to rule out referred pain from the lumbar spine, sacroiliac joints, or knee 6