Summary

Supracondylar Humerus Fractures are the most common pediatric elbow fracture (60%) and a true orthopaedic emergency. They typically occur in children aged 5-7 due to a fall on an outstretched hand (FOOSH). The fracture line passes through the thin olecranon fossa. Gartland Type III (completely displaced) fractures are notoriously dangerous due to the proximity of the Brachial Artery and Median Nerve (specifically Anterior Interosseous Nerve). The "Pink Pulseless Hand" is a unique clinical entity requiring urgent reduction but not necessarily exploration. Treatment ranges from casting (Type I) to urgent closed reduction and percutaneous pinning (CRPP) for displaced fractures. [1,2,3]

Key Facts

• The Age Rule: Peaks at 5-7 years because the supracondylar bone is thin and remodeling, and ligament laxity allows hyperextension.
• Most Common Nerve Injury: Anterior Interosseous Nerve (AIN) (branch of Median). Test by asking child to make an "OK" sign.
• Most Common Vascular Injury: Brachial Artery. Kinked or entrapped.
• Volkmann's Ischaemic Contracture: The devastating end-result of a missed compartment syndrome / vascular injury. Flexion contracture of the wrist and fingers.

Clinical Pearls

"The Pucker Sign": A dimple in the skin anteriorly. This means the proximal bone spike has pierced the Brachialis muscle and is button-holing the dermis. Danger: The Neurovascular bundle is often trapped with it.

"Pink Pulseless Hand": The hand is warm and pink (collateral flow) but the radial pulse is absent.

• Action: Urgent Reduction.
• Outcome: Pulse returns in >80% after reduction. If pink/warm after reduction but still pulseless -> Observe. Do NOT explore immediately.

"White Pulseless Hand": The hand is cold and pale.

• Action: Urgent Reduction -> If no pulse -> Explore Brachial Artery.

              SUPRACONDYLAR FRACTURE
                        ↓
            GARTLAND CLASSIFICATION?
      ┌─────────┬───────────────┴───────────────┐
    TYPE I    TYPE II                        TYPE III
  (Undisplaced) (Hinge)                      (Off-ended)
      ↓         ↓                               ↓
    CAST       REDUCTION NEEDED?         IS HAND PINK OR WHITE?
   (3-4w)      ┌───────┴──────┐          ┌───────┴───────┐
              NO             YES       PINK            WHITE
              ↓               ↓         ↓                ↓
             CAST          SURGERY    URGENT          EMERGENCY
                          (K-Wires)  REDUCTION        REDUCTION
                                     (K-Wires)            ↓
                                        ↓             PULSELESS?
                                     PULSE?           ┌───┴───┐
                                    YES   NO        YES      NO
                                     ↓    ↓          ↓       ↓
                                    WARD OBSERVE   WARD   VASCULAR
                                        (48h)             EXPLORE

1. Conservative (Type I)

• Indication: Undisplaced. Anterior humeral line intersects capitellum.
• Device: Long Arm Cast (Above Elbow). Elbow at 90 degrees.
• Duration: 3-4 weeks.

2. Surgical: CRPP (Closed Reduction Percutaneous Pinning)

• Indication:
  • Type II (with malrotation or extension angulation).
  • Type III (All).
  • Neurovascular compromise.
• Technique:
  1. Reduction: "Milking" maneuver to free soft tissue -> Traction -> Flexion -> Pronation (locks the medial hinge).
  2. Pinning: Two or three 1.6mm K-wires.
• Pin Configuration (The Great Debate):
  • Lateral Divergent (2 pins): Safer. Avoids Ulnar nerve. (Preferred by most modern surgeons).
  • Crossed (1 Medial, 1 Lateral): Biomechanically stronger. Risk of Ulnar Nerve Injury (3-5%) from the medial pin.
  • Guideline: Use Lateral pins first. Add a Medial pin only if unstable, and extend the elbow to protect the nerve while drilling.

The Lateral vs Crossed Pin Debate (Skaggs et al. 2004)

• Study: Biomechanical and Clinical review.
• Findings: Lateral entry pins (if divergent) provide sufficient stability for almost all fractures. Crossed pins add stability but introduce Ulnar Nerve risk.
• Recommendation: Start with 2 Lateral pins. If unstable, adds a 3rd Lateral pin. Only use Medial pin as last resort.

AAOS Guidelines (2011)

• Pink Pulseless Hand: Do not explore immediately. Reduce, pin, and observe. Warmth is the best indicator of perfusion (collateral flow).
• Night Surgery: Type III fractures should be done urgently, but can wait until morning unless there is vascular compromise or compartment syndrome. (Operating with a fresh team is safer than tired team at 3am).

How bad is the break?

The bone has snapped just above the elbow joint. It's a common injury in kids because the bone is thin there.

Does he need surgery?

Because the bones have moved apart ("Type 3"), we need to put them back. If we just used a cast, they would slip, and the arm would heal crooked. We use metal wires (pins) to hold it.

Are there risks?

The main worry is the blood vessels and nerves that run right next to the jagged bone. We checked his pulse and nerve function, and they are okay right now. Sometimes the surgery can "stretch" the nerve, causing temporary numbness, but this almost always recovers.

What about the pins?

The pins stick out of the skin but are covered by the cast. We pull them out in the clinic in 3-4 weeks. It sounds scary, but it doesn't really hurt—it feels like a weird tug. No anaesthetic is needed for removal.

Will the arm be straight?

We aim for perfect alignment. Sometimes, if the bone collapses slightly while healing, the arm might look a bit "gunstock" (tilted in). This is usually just cosmetic and doesn't stop them playing sports.

Q1: What is the significance of the Anterior Humeral Line? A: On a lateral X-ray, more than 1/3 of the capitellum should be anterior to this line. If less (or none) is anterior, it indicates extension deformity of the distal fragment.

Q2: How do you manage a "Pink Pulseless Hand" post-reduction? A: If the hand is warm, pink, and has brisk capillary refill, simply admit and observe (48 hours). The collateral circulation is sufficient. Do not explore the artery. The pulse usually returns.

Q3: Which displacement causes which nerve palsy? A:

• Posterolateral displacement -> Median/AIN nerve (and Brachial Artery) risk. (The shaft goes Anteromedial, hitting the median nerve).
• Posteromedial displacement -> Radial nerve risk. (The shaft goes Anterolateral).

(End of Topic)