Hip Dislocation in a 3-Year-Old Girl
This is an orthopedic emergency requiring immediate closed reduction within 6 hours to minimize the risk of avascular necrosis (AVN) of the femoral head 1, 2, 3, 4.
Immediate Evaluation
Clinical Assessment
Look for these specific findings:
- Leg position: Shortened, adducted, and internally rotated (posterior dislocation - 90% of cases) 2, 3
- Severe pain with any attempted movement
- Limited passive range of motion of the affected hip 2
Imaging
- Plain radiograph of the pelvis is the initial and essential imaging study 2, 4
- This will confirm the dislocation and direction (posterior vs. anterior)
- No need for advanced imaging before reduction unless there's concern for associated fractures
Immediate Management
Urgent Closed Reduction
- Perform under general anesthesia or deep sedation 2, 4
- Use the Allis maneuver for reduction 2
- Time is critical: Reduction within 6 hours significantly reduces AVN risk; risk increases dramatically after 6 hours 1, 3, 4, 5
- Verify reduction with fluoroscopy/image intensifier 4
If Closed Reduction Fails
- Up to 25% of cases require open reduction in the operating room 1
- Do not delay beyond multiple gentle attempts - proceed to OR if unsuccessful 3, 4
Post-Reduction Protocol
Immobilization
- Apply hip spica cast (one and a half hip spica) with hips in 30° abduction 2, 4
- Duration: 3-6 weeks of immobilization 2, 4
Weight-Bearing
- After cast removal, refer to physical therapy
- Allow gradual weight-bearing as tolerated starting at 2-4 weeks post-reduction 5
- Progress to full weight-bearing over subsequent weeks
Follow-Up Monitoring
Critical Surveillance for AVN
- MRI at 6 months post-injury to detect early AVN 4, 5
- Repeat MRI at 12-18 months for continued surveillance 4
- Clinical follow-up with serial radiographs
Important Prognostic Factors
The risk of AVN (the most serious complication) is determined by:
- Time to reduction (most critical factor - keep under 6 hours) 1, 3, 4, 5
- Gentleness of manipulation during reduction (avoid iatrogenic injury) 4
- Open dislocations carry higher AVN risk 5
Key Clinical Pitfalls
Do not miss the "golden window" - pediatric hip dislocations require much less energy than adult dislocations and can occur with seemingly minor trauma 1, 2, 4. A high index of suspicion is essential, as this injury can result from low-velocity mechanisms like falls from playground equipment or twisting injuries 2, 4.
Avoid aggressive or repeated reduction attempts - gentle manipulation is paramount to prevent iatrogenic chondrolysis and osteonecrosis 4.
The prognosis is generally favorable with prompt recognition and reduction, with multiple case reports showing normal outcomes at follow-up when managed appropriately 1, 2, 4.