Complications with Pediatric Femur Fractures

Courtesy: Martin Herman, MD

 

Pediatric femoral shaft fractures

• Common pediatric fracture.
• Excellent healing potential.
• Union is usually achieved without difficulty.
• Main concerns are limb length and alignment rather than fracture healing.

Common complications

• Shortening (most common).
• Malunion.
• Delayed union (rare).

AAOS Based Treatment Guidelines

0 to 6 months

• Pavlik harness.

6 months to 5 years

• Immediate hip spica cast.

5 to 11 years

• Elastic intramedullary nails.

More than 11 years

• Elastic nails or rigid locked intramedullary nails depending on patient factors.

Important point

• Age is only a guideline.
• Treatment should be individualized.

Factors Affecting Treatment Choice

Factors to consider

• Age.
• Weight of the child.
• Femoral canal size.
• Fracture pattern.
• Length stability.
• Associated injuries.
• Polytrauma.

Most important concept

• Failure to recognize length unstable fractures is the commonest cause of treatment failure.

Pavlik Harness

Indications

• Infants younger than 6 months.

Advantages

• Functional immobilization.
• Easy nursing care.
• Better skin monitoring.

Disadvantages

• Less pain control initially.
• Difficult in suspected child abuse cases.

Hip Spica Cast

Indications

• Children aged 6 months to 5 years.

Principles

• Accept 1.5 to 2 cm of shortening due to expected overgrowth.
• Accept up to 20° of angulation in appropriate patients.
• Overgrowth commonly occurs between 2 and 10 years of age.

Common problem

• Hygiene difficulties.

Elastic Intramedullary Nails

Ideal indications

• Midshaft fractures.
• Length stable fractures.
• Weight less than 50 kg.

Advantages

• Minimally invasive.
• Reliable outcomes when properly indicated.

Contraindications

• Comminuted fractures.
• Long oblique fractures.
• Heavy children.

Complications

• Shortening.
• Nail prominence.
• Malunion.

Key concept

• Flexible nails should not be used for length unstable fractures.

Rigid Intramedullary Nails

Indications

• Older children and adolescents.
• Larger femoral canal.
• Length unstable fractures.

Preferred entry point

• Lateral trochanteric entry.

Avoid

• Piriformis entry due to risk of avascular necrosis of the femoral head.

Submuscular Plating

Indications

• Comminuted fractures.
• Length unstable fractures.

Advantages

• Functions as an internal external fixator.
• Preserves fracture biology.

External Fixation

Indications

• Polytrauma.
• Open fractures.
• Temporary stabilization.
• Severe soft tissue injury.

Length Stability

Length stable fractures

• Transverse fractures.
• Short oblique fractures.
• Suitable for elastic intramedullary nails.

Length unstable fractures

• Comminuted fractures.
• Long oblique fractures.
• Segmental fractures.
• Better treated with plating, rigid intramedullary nails, or external fixation.

Common Clinical Pitfalls

Treatment errors

• Using elastic nails for length unstable fractures.
• Ignoring patient weight.
• Using undersized nails.
• Poor nail configuration.
• Leaving distraction at the fracture site.

Compliance issues

• Hyperactive children.
• Children with autism.
• May require supplementary hip spica immobilization.

Special Situations

Tweener age group (10 to 16 years)

• Treatment based on weight and canal size rather than age.
• Rigid intramedullary nail is often preferred.

Pathological fractures

• Always consider a simple bone cyst or other underlying pathology.

Exam Pearls

Most common complication

• Shortening.

Overgrowth phenomenon

• Approximately 1.5 to 2 cm.
• Common between 2 and 10 years of age.

Best indication for elastic nails

• Midshaft, length stable fracture in a child weighing less than 50 kg.

Contraindications to elastic nails

• Comminuted fractures.
• Long oblique fractures.
• Segmental fractures.
• Heavy children.

Piriformis entry nail complication

• Avascular necrosis of the femoral head.

Submuscular plating

• Functions as an internal external fixator.

Key Take Home Message

Management principles

• Pediatric femoral shaft fractures usually heal well.
• Success depends on choosing treatment according to fracture stability rather than age alone.
• Always assess length stability, patient size, and fracture pattern before selecting fixation.