CIM Case: Paediatric Forearm Fracture

Clinical Scenario

Patient: 13-year-old boy Presentation: Fall at football 2 hours ago, landed on outstretched right arm, obvious deformity of forearm, immediate pain and swelling Relevant history: No previous fractures, right-hand dominant, otherwise healthy, normal growth and development, competitive footballer Examination findings:

• Obvious angular deformity of right mid-forearm
• Swelling and tenderness over both radius and ulna
• Unable to rotate forearm due to pain
• Fingers warm, pink, moving freely
• Radial pulse palpable
• No compartment tension
• Full finger flexion and extension
• Sensation intact to light touch all digits
• Elbow and wrist joints above and below appear stable

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Investigations Provided

Laboratory Results

Imaging

Image 1: AP and Lateral Radiographs of Right Forearm

Radiological features:

• Both bone midshaft forearm fracture
• Radius: Complete transverse fracture at junction of middle and distal thirds
  • 25° apex dorsal angulation
  • 80% cortical contact
  • Mild rotational displacement
• Ulna: Complete oblique fracture at mid-diaphysis
  • 20° apex volar angulation
  • Bayonet apposition (no overlap)
• No extension to wrist or elbow joints
• No plastic deformation of either bone
• Radial head in normal position (not Monteggia)
• Open physes - approaching skeletal maturity

Classification: Diaphyseal both bone forearm fracture, displaced, closed

Questions & Model Answers

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Key Teaching Points

Pattern Recognition

This pattern suggests paediatric forearm fracture requiring intervention:

• Older child/adolescent (>10 years)
• Complete both bone fracture
• Angulation exceeding age-appropriate limits
• Midshaft location (limited remodelling)

Distinguish from Monteggia/Galeazzi:

Always get elbow and wrist X-rays to exclude associated injury.

Critical Management Points

1. Age determines acceptable angulation - <10 years more forgiving, >10 years stricter
2. Rotation does not remodel - must be corrected at initial reduction
3. MUA is reasonable first attempt - but set expectations for older children
4. ESIN for younger children, plates for adolescents - near skeletal maturity = adult fixation
5. Henry approach for radius - protect PIN proximally, ligate leash of Henry
6. Plate removal is optional - not mandatory if asymptomatic, refracture risk exists

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Common Examiner Follow-ups

Q: "This child is 6 years old with the same fracture. How would your management differ?"

For a 6-year-old:

• Greater remodelling potential - more growth remaining
• More forgiving limits - up to 15° acceptable at midshaft
• MUA more likely to succeed - greenstick patterns common
• If MUA fails, consider ESIN - works well in this age group
• Plate removal almost always done - avoid permanent hardware in growing child

The 6-year-old would likely be managed with MUA and cast, with ESIN reserved for failure.

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Q: "The fracture is plastic deformation of the ulna with a radius fracture. How do you manage this?"

Plastic deformation (bowing) management:

• Recognise on X-ray: Curved bone without clear fracture line
• Remodelling is limited for plastic deformation
• Correction needed if >10-15° bow
• Technique: Apply 3-point bending force under GA for 2-3 minutes
• May feel/hear cortical microcracking
• Cast in corrected position
• More difficult to correct than complete fracture

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Q: "At 1-week follow-up, the fracture has displaced in cast. What are your options?"

Re-displacement in cast:

• Common - up to 30% of both bone fractures
• If still within acceptable limits - continue cast, close follow-up
• If outside limits:
  • Re-manipulation (if within 2 weeks, single attempt)
  • ORIF if re-manipulation fails or already attempted once
• Prevention: Good initial moulding, close early follow-up, above-elbow cast

After 2 weeks, callus formation makes closed reduction difficult. Proceed to ORIF if unacceptable alignment at that point.

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Q: "What is the role of ESIN in paediatric forearm fractures?"

ESIN (Elastic Stable Intramedullary Nailing):

• Ideal age: 6-12 years
• Ideal fracture: Simple transverse or short oblique, midshaft
• Contraindications: Comminuted, very proximal/distal, open
• Technique: Retrograde radius, antegrade ulna, prebent nails
• Outcomes: 90%+ union, good functional results
• Complications: Hardware prominence, delayed union, loss of reduction
• Removal: At 6-12 months, often under local anaesthesia

ESIN offers a minimally invasive option between casting and plating.

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Related Topics

• Monteggia Fracture-Dislocation
• Galeazzi Fracture
• Paediatric Elbow Fractures
• Forearm Compartment Syndrome
• ESIN Technique
• Paediatric Fracture Principles