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Difficulty: HardOrthopedic Surgery

An otherwise healthy 7-year-old boy arrives at the trauma bay 45 minutes after falling from a playground structure onto his outstretched right hand. He complains of excruciating elbow pain and refuses to move his arm. Vital signs are within normal limits for his age. On physical examination, the right elbow is markedly swollen with an S-shaped deformity. The skin over the antecubital fossa is intact, taut, and slightly ecchymotic. Neurologic evaluation reveals an inability to flex the distal interphalangeal joints of the index finger and thumb to make an "OK" sign, though wrist extension and finger abduction are intact. The radial pulse is non-palpable and cannot be detected with a handheld Doppler ultrasound. However, the right hand is warm and pink, with a capillary refill time of 2 seconds. Radiographs of the right elbow reveal a completely displaced extension-type supracondylar humerus fracture. Which of the following is the most appropriate next step in management?

  1. Closed reduction and percutaneous pinningAnswer
  2. B
    CT angiography of the right upper extremity
  3. C
    Immediate open surgical exploration of the brachial artery
  4. D
    Application of a long-arm splint and admission for neurovascular observation
  5. E
    Intravenous heparin administration

Answer

Closed reduction and percutaneous pinning
This patient presents with a completely displaced (Gartland type III) extension-type supracondylar humerus fracture accompanied by a classic 'pulseless, pink hand.' The inability to make an 'OK' sign indicates an anterior interosseous nerve (AIN) injury, which is the most commonly injured nerve in this specific fracture pattern. In a pulseless, pink hand, collateral circulation is sufficient to maintain viability, and the primary issue is mechanical kinking, tethering, or localized vasospasm of the brachial artery over the sharp proximal bone fragment. The standard of care is urgent closed reduction and percutaneous pinning (CRPP). Reducing the fracture restores anatomic alignment, which relieves the tension on the neurovascular bundle and typically restores the palpable pulse. Because the hand is well-perfused, there is no indication to delay skeletal stabilization for advanced imaging or vascular surgery.

Step-by-Step Solution

1
Identify the primary diagnosis and specific complications based on the clinical presentation.
The patient has a completely displaced (Gartland type III) extension-type supracondylar humerus fracture complicated by Anterior Interosseous Nerve (AIN) neuropraxia (inability to make the 'OK' sign) and a 'pulseless, pink hand'.
Accurate identification of the fracture pattern and neurovascular status dictates the treatment algorithm.
2
Analyze the vascular status of the extremity.
The radial pulse is absent (even on Doppler), but the hand remains warm, pink, and has normal capillary refill (< 2 seconds), indicating adequate collateral perfusion.
Differentiating between a 'pulseless, pink hand' (well-perfused) and a 'pulseless, pale hand' (ischemic) is critical for determining the urgency and type of intervention.
3
Select the most appropriate intervention according to standard pediatric orthopedic trauma algorithms.
The standard of care for a pulseless, pink hand in this setting is urgent closed reduction and percutaneous pinning (CRPP) without delaying for vascular studies.
The absent pulse is typically due to mechanical kinking or local spasm of the brachial artery over the proximal fracture fragment. Realignment of the bone reliably relieves this kinking and often restores the pulse.

Key Concept

Management of a pulseless but well-perfused (pink) hand in the setting of a pediatric displaced supracondylar humerus fracture.
Estimated Time:1m 30s
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Topics

Orthopedic Surgery

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