Summary

A Pulled Elbow (Radial Head Subluxation) is the most common upper limb injury in toddlers (1-4 years). It involves the Annular Ligament slipping proximally over the radial head and becoming entrapped in the radiocapitellar joint. The classic mechanism is axial traction on an extended, pronated forearm ("swinging the child"). The child presents with Pseudoparalysis: arm held by the side, pronated, refusing to use it, but not distressed unless moved. Reduction is famously satisfying (immediate fix). [1,2,3]

Key Facts

• The "Popcorn Test": After reduction, the child usually cries briefly, then settles. To confirm success, offer them a treat/toy (Popcorn/Smarties) that requires them to reach out and supinate. If they use the arm spontaneously within 10-15 minutes, it is fixed.
• Mechanism: Traction on a straight arm. (Lifting child by wrists, swinging, pulling child away from danger).
• Age Limit: Rare after age 5. (The radial head grows wider than the neck, preventing the ligament slipping off).

Clinical Pearls

"Hyper-pronation Beats Supination": The traditional teaching is Supination + Flexion. However, RCTs show that Hyper-pronation has a higher first-attempt success rate and is less painful.

"No X-rays Needed": If the history is classic (pull) and exam is classic (no swelling), do NOT X-ray. It's purely clinical. X-ray only if reduction fails or mechanism involves a fall.

"The Click": A palpable (sometimes audible) click during the reduction maneuver is the feeling of the ligament snapping back into place. It usually signifies success.

                 TODDLER NOT USING ARM
                        ↓
                  HISTORY OF PULL?
             (Exclude Fall / Swelling)
             ┌──────────┴──────────┐
           YES                    NO / UNSURE
            ↓                      ↓
      CLINICAL DIAGNOSIS          X-RAY ELBOW
      (No X-ray needed)         (Rule out #)
            ↓                      ↓
         REDUCTION               NORMAL?
      (Hyper-pronation)            ↓
            ↓                   REDUCTION
         CLICK?
        (Wait 15m)
            ↓
      FUNCTION RETURN?
      (Popcorn Test)
     ┌──────┴──────┐
    YES           NO
     ↓             ↓
 DISCHARGE      TRY SUPINATION
                   ↓
                 FAIL?
                   ↓
                 X-RAY

1. The Hyper-Pronation Method (First Line)

• Technique:
  1. Hold the child's elbow in one hand (thumb on radial head).
  2. Hold the child's hand in a handshake.
  3. Firmly Rapidly Pronate the wrist while extending the arm.
• Success: Palpable click.

2. The Supination-Flexion Method (Classic)

• Technique:
  1. Hold elbow and wrist.
  2. Supinate the forearm fully (palm to ceiling).
  3. Then Flex the elbow rapidly towards the shoulder.
• Success: Click felt on flexion.

3. Failed Reduction

• If "Click" felt but child still won't use it: Wait 20 mins. (Pain memory).
• If NO click and child won't use it: X-ray to rule out fracture.
• If X-ray normal: Place in collar-and-cuff sling. Spontaneous reduction usually occurs within 24h.

Cochrane Review (2017)

• Comparison of Pronation vs Supination methods.
• Result: Hyper-pronation has a higher success rate (90% vs 70% first attempt) and is perceived as less painful.
• Recommendation: Hyper-pronation should be the first-line technique.

What happened?

It's commonly called "Nursemaid's Elbow". A small ligament (like a rubber band) that holds the elbow bone in place has slipped over the bone and got stuck. It's like a jammed zipper.

Is it broken?

No, nothing is broken. It is a subluxation (a partial slip).

The Fix

I will do a quick movement to twist the arm. It will hurt for one second, they will cry, but then the ligament will pop back in. After about 10 minutes, the pain will vanish and they will use the arm normally.

Can it happen again?

Yes, the ligament is loose. Avoid swinging them by the arms or lifting them up by the hands until they are about 5 years old.

Q1: What is the anatomical pathology of a pulled elbow? A: Axial traction causes the radial head to move distally. The Annular Ligament slips proximally over the head. When traction is released, the ligament is trapped between the radial head and the capitellum.

Q2: Why does it rarely occur after age 5? A: The radial head ossifies and changes shape. It becomes more bulbous (mushroom-shaped), becoming wider than the radial neck. This bony mechanical block prevents the annular ligament from slipping over it.

Q3: Describe the "Popcorn Test". A: A functional test of reduction. Following the maneuver, the child is left alone for 10-15 minutes to allow the acute pain to subside. They are then offered a reward (popcorn/toy) with their good hand restrained. If they reach out, grab it, and supinate to put it in their mouth, the reduction is confirmed.

(End of Topic)