Summary

Supracondylar fractures of the humerus are the most common elbow fracture in children (5-7 years). They usually result from a Fall On Outstretched Hand (FOOSH) with the elbow in extension (Extension Type - 95%). The distal fragment is pushed posteriorly. The fracture is notoriously dangerous due to the proximity of the Brachial Artery and Median Nerve (specifically Anterior Interosseous Nerve). The Gartland Classification guides management: Undisplaced (I) are casted; Displaced (II/III) require Closed Reduction and Percutaneous Pinning (CRPP). [1,2,3]

Key Facts

• The "Fat Pad Sign": In a non-displaced fracture (Type I), the fracture line may be invisible. The only sign is elevation of the anterior or posterior fat pad (Sail Sign) due to haemarthrosis.
• Neurological Injury: 10-20% incidence. AIN (Anterior Interosseous Nerve) is most common (cannot flex IPJ of thumb/index). Radial Nerve is second.
• Vascular Injury: 1% have a pulseless hand. "Pink Pulseless" needs urgent reduction. "White Pulseless" needs vascular surgery.

Clinical Pearls

"Puckered Skin is a Warning": If you see a dimple in the skin anteriorly, the proximal bone spike has buttonholed through the Brachialis muscle. This is a "complex" reduction. Do NOT just yank it—you need to milk the soft tissue.

"The OK Sign": Always ask the child to make an OK sign. If they make a pincer (flat) pinch instead of a round O, the AIN is gone.

"Gunstock Deformity": Malunion leads to Cubitus Varus. It is cosmetic, not functional, but parents hate it.

                 ELBOW INJURY (CHILD)
                        ↓
                 ASSESS NEUROVASCULAR
             ┌──────────┴──────────┐
        PULSELESS              PULSE PRESENT
            ↓                      ↓
      REDUCE IN ED              X-RAY
      (immediately)                ↓
                              GARTLAND?
                     ┌─────────────┼─────────────┐
                   TYPE I        TYPE II      TYPE III
                     ↓             ↓             ↓
                CAST 3wks    REDUCE + K-WIRE   REDUCE + K-WIRE
                             (Urgent List)     (Urgent List)

1. Type I (Undisplaced)

• Treatment: Above Elbow Backslab (Cast) at 90° flexion.
• Duration: 3 weeks.
• Follow-up: X-ray at 1 week to ensure no slip.

2. Type II (Angulated)

• Treatment: Closed Reduction and Percutaneous Pinning (CRPP).
• Why pin?: Casting a Type II often leads to loss of reduction (varus drift) when swelling subsides.
• Technique: 2 Lateral Divergent K-wires.

3. Type III (Displaced)

• Treatment: CRPP.
• Urgency: As soon as possible (next available list), unless vascular compromise (immediate).
• Technique: Milk the soft tissue. Reduce. Pin with 2 Lateral wires (sometimes add a Medial wire if unstable, but watch the Ulnar nerve).

4. The "Pink Pulseless Hand"

• Hand is warm and pink (collateral flow) but no radial pulse.
• Action: Urgent Reduction and Pinning.
• Post-Op: If pulse returns -> Great. If hand remains pink -> Observe. If hand turns white -> Explore.

The BOAST 11 Guidelines

• Timing: Surgery can be done next day (daylight hours) if neurovascularly intact. No need to operate at 3am unless ischaemic or compartment syndrome.
• Pinning: Lateral entry pins are preferred to avoid iatrogenic Ulnar nerve injury.

Wilkins Modification

• Added Type IIA (No rotation) and IIB (Rotation). IIB definitely needs pinning.

What is broken?

The bone just above the elbow joint (humerus) has snapped. It's a very common break in kids who fall off climbing frames.

Does it need an operation?

Because the bones have moved apart (displaced), we can't just put a cast on. The bone ends are dangerously close to the main artery and nerves of the arm. We need to put the child to sleep, pull the bone back straight, and put 2 metal wires (pins) in to hold it.

The Pins

The pins stay under the skin (or stick out with a dressing). They hold the bone for 3-4 weeks. Once the bone is sticky (healed), we pull the pins out in the clinic (it feels weird but doesn't hurt much).

Will the arm be straight?

We try our best to get it perfect. Sometimes, even with perfect surgery, the arm heals with a slight bend (Gunstock), but this doesn't stop them using it for everything.

Q1: Describe the Anterior Humeral Line. A: On a true lateral X-ray, a line drawn down the anterior surface of the humerus should pass through the middle third of the capitellum ossific nucleus. If it passes anterior to the capitellum, the fracture is extended (Type I/II).

Q2: How do you assess the Anterior Interosseous Nerve (AIN) in a 5-year-old? A: Ask them to make an "OK Sign" (touch tip of thumb to tip of index finger). This requires FPL and FDP (supplied by AIN). If AIN is palsied, they will press the pulps together (flat pinch) because they can't flex the IPJs.

Q3: What is "Volkmann's Ischaemic Contracture"? A: The sequela of untreated compartment syndrome. Infarction of the deep flexor compartment leads to fibrosis and shortening of the muscles. Result: Flexed wrist, extended MCPJs, flexed IPJs (Claw), and sensory loss.

(End of Topic)