What are the treatment options for leg length discrepancy in a pediatric patient resulting from a fracture?

Treatment Options for Leg Length Discrepancy from Pediatric Fracture

Children with significant limb length discrepancy resulting from a pediatric fracture should be referred to a pediatric orthopedic surgeon for specialized management. 1

Assessment and Diagnosis

• Leg length discrepancy (LLD) is a common complication following pediatric femoral fractures
• Evaluation should include:
  • Clinical measurement of limb length
  • Weight-bearing radiographs with calibration rule for precise measurements 2
  • Assessment of mechanical axis of the limb
  • Determination of skeletal maturity

Understanding Post-Fracture LLD Patterns

• Femoral fractures in children aged 7-13 typically result in limb overgrowth of approximately 1 cm 3
• Factors affecting LLD after fracture:
  • Age at time of fracture (most significant overgrowth occurs between 4-9 years) 4
  • Number of repositions (2 or more increases overgrowth) 4
  • Degree of axial deviation (>10 degrees increases overgrowth) 4
  • Delayed surgical treatment (>48 hours) 4
  • Type of fixation (plate fixation particularly associated with overgrowth) 4

Treatment Options

Non-Surgical Management (For LLD <2 cm)

• Observation: Appropriate for mild discrepancies, especially in growing children where spontaneous correction may occur
• Shoe lifts/modifications:
  • External lift for discrepancies of 1-2 cm
  • Internal shoe lift for smaller discrepancies

Surgical Management (For LLD >2 cm or symptomatic cases)

1. Epiphysiodesis (growth arrest):

   • Indicated for growing children with predicted LLD of 2-5 cm
   • Involves surgical arrest of growth plate in longer limb
   • Timing is critical and based on bone age assessment

2. Limb lengthening procedures:

   • Indicated for LLD >5 cm or in skeletally mature patients
   • Options include:
     • Distraction osteogenesis using external fixation (Ilizarov method)
     • Intramedullary lengthening devices for older children/adolescents
     • Combined techniques may be necessary for complex cases 1

3. Shortening procedures:

   • Indicated in skeletally mature patients with moderate discrepancies
   • Involves surgical shortening of the longer limb

Treatment Algorithm Based on Severity

1. Mild LLD (0-2 cm):

   • Observation or shoe modification
   • Regular follow-up until skeletal maturity

2. Moderate LLD (2-5 cm):

   • In growing children: Epiphysiodesis of longer limb
   • In skeletally mature: Shortening procedure or limb lengthening

3. Severe LLD (>5 cm):

   • Limb lengthening procedures
   • May require multiple surgical interventions

Follow-up Recommendations

• Regular clinical and radiographic follow-up is essential until skeletal maturity 5
• Radiographs recommended at 12-month intervals or sooner if clinical worsening 2
• Monitor for potential complications including angular deformities, joint contractures, or neurovascular issues

Important Considerations

• Treatment should aim for equal limb lengths at skeletal maturity
• In children aged 7-13 with femoral fractures, anticipate approximately 1 cm of overgrowth 3
• Fracture management in children 7-13 years should aim for 1 cm overlap at union to compensate for expected overgrowth 3
• Angular deformities should be corrected, particularly in children over 10 years 3
• LLD may continue to change beyond the typical 2-year post-fracture period 4

Pitfalls to Avoid

• Assuming LLD will resolve spontaneously in all cases
• Delaying referral to pediatric orthopedic specialists for significant discrepancies
• Overlooking the psychological impact of LLD and visible deformity on children
• Failing to consider that LLD can continue to change more than 2 years post-fracture 4