What is the treatment for a dislocation of a femoral head component?

Treatment for Dislocation of Femoral Head Component

The treatment for a dislocation of a femoral head component requires prompt closed reduction as the initial management, followed by appropriate stabilization measures based on the specific cause of dislocation and patient factors.

Initial Management

Closed Reduction

• Perform closed reduction under adequate sedation or anesthesia

• For posterior dislocations (most common):

  • Apply longitudinal traction with internal rotation of the hip 1
  • An assistant may need to stabilize the pelvis during the procedure

• For anterior dislocations:

  • Apply inline traction with external rotation
  • An assistant may push on the femoral head or pull the femur laterally to assist reduction 1

Post-Reduction Imaging

• Obtain immediate post-reduction radiographs to confirm:
  • Proper positioning of the femoral head component
  • Absence of fractures or component damage
  • Adequate joint space 2

Secondary Management Based on Etiology

For Traumatic Dislocations with Associated Fractures

• If femoral head fractures are present:
  • Consider surgical hip dislocation approach for direct visualization and repair
  • Use 2.7-mm nonabsorbable screws for fixation of displaced fragments 3
  • This approach allows for 360° view of the femoral head and facilitates anatomic reduction 3

For Prosthetic Hip Dislocations

• First-time dislocation:

  • Bracing or hip precautions for 6-8 weeks
  • Activity modification and physical therapy

• Recurrent dislocations:

  • Surgical revision may be necessary to address:
    • Component malposition
    • Inadequate soft tissue tension
    • Impingement issues 4

Special Considerations

Open Dislocations

• Require emergency management:
  • Immediate wound debridement
  • Intravenous antibiotics
  • Reduction and stabilization
  • Consider external fixation in severe cases 5

Chronic Dislocations

• Can lead to severe complications including:
  • Pressure sores
  • Potential protrusion through skin in neglected cases
  • May require partial or complete removal of prosthetic components 4

Complications to Monitor

• Avascular necrosis (AVN) of the femoral head

  • More common in traumatic dislocations
  • May require total hip arthroplasty if severe 5

• Post-traumatic arthritis

  • Monitor for joint space narrowing and osteophyte formation
  • May develop even after successful reduction 3

• Heterotopic ossification

  • Can occur following surgical intervention
  • May require prophylaxis in high-risk patients 3

Follow-up Protocol

• Regular radiographic assessment at:

  • 2 weeks post-reduction
  • 6 weeks post-reduction
  • 3 months post-reduction
  • 6 months post-reduction

• MRI may be indicated if:

  • Persistent pain despite reduction
  • Suspicion of occult fracture or osteonecrosis 2

The treatment approach should be determined by the specific type of dislocation, associated injuries, and patient factors. Timely evaluation and treatment are essential to minimize complications and optimize outcomes.