Displaced Pediatric Supracondylar Fracture With a Pulseless Pink Hand
A 6-year-old boy fell approximately 2 meters from the monkey bars onto his left elbow 3 hours ago. He holds the arm in extension and refuses to move it. The elbow is markedly swollen with a superficial abrasion over the olecranon; there is no open wound. Radiographs show a supracondylar humerus fracture with complete displacement, no cortical contact between the distal fragment and the shaft, and the distal fragment displaced posteriorly and medially; the radiocapitellar line is intact. The radial pulse is not palpable and is not detected by Doppler, but the hand is pink and warm, capillary refill is 2 seconds, and oxygen saturation is 99 percent. Sensation to light touch is intact; he will not cooperate with motor testing because of pain. He weighs 22 kg, has no allergies, and last ate at 11:00; it is now 15:00. His mother is anxious and asks whether the arm will be straight again.
1. Classify the fracture, explain the significance of the pulseless pink hand, and outline your immediate priorities and disposition.
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This is a Gartland III supracondylar humerus fracture: completely displaced with no cortical contact between the distal fragment and the shaft. The intact radiocapitellar line confirms the elbow joint itself is reduced.
A pulseless pink hand is a vascular injury with adequate collateral perfusion. The brachial artery is tethered against the anterior distal humerus and is kinked, contused, or intimal-injured. Because the hand is warm and pink with brisk capillary refill, the limb is not immediately unsalvageable, but this is not a fracture to observe overnight. It warrants urgent closed reduction and percutaneous pinning in the operating room, ideally within a few hours, because reduction restores flow in the majority of cases.
Plan: keep him NPO, obtain IV access, give weight-based analgesia (about 0.1 mg/kg morphine), splint in a position of comfort and avoid excessive elbow flexion, notify the on-call orthopaedic surgeon, and consent for closed reduction and pinning with possible open reduction or vascular exploration. If the pulse does not return after an anatomically acceptable reduction, or if the hand becomes cool or dusky, proceed to vascular assessment (CT angiography or formal exploration) rather than continued observation. Document serial vascular checks.
2. Eight hours after closed reduction and pinning with two lateral pins and a long-arm cast, he wakes crying with pain 10/10 that is unrelieved by morphine. The forearm is tense and he cries with passive extension of the fingers. What is your interpretation and immediate management, and which findings would you not rely on?
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This is acute compartment syndrome until proven otherwise. Pediatric compartment syndrome is easy to miss because children cannot articulate the pain and the classic signs are late. The warning signs here are escalating analgesia requirement, pain out of proportion, a tense forearm, and pain with passive stretch.
Immediate actions: cut the cast and all padding down to skin along its full length, remove the underlying dressing, and keep the arm at heart level rather than elevated above the heart, which lowers perfusion pressure. Reassess within 15-30 minutes. Give opioid analgesia and reassess.
A palpable radial pulse does not exclude compartment syndrome; pulses are usually preserved until very late. Do not wait for pallor, paralysis, or pulselessness. If pain, tension, or pain with passive stretch persist after cast release, or the child becomes agitated or difficult to examine, proceed to fasciotomy without waiting for pressure measurement. If the examination is unreliable, measure compartment pressures: a delta pressure (diastolic minus compartment pressure) below 30 mmHg supports fasciotomy. Time to fasciotomy is the main predictor of long-term function; delay causes Volkmann contracture.
3. At 3 weeks, the mother calls because he has a temperature of 38.4 degrees Celsius and the pin sites look red with a small amount of clear drainage. How do you handle this call?
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Fever with pin-site erythema raises pin tract infection, but also cellulitis and, rarely, septic arthritis or osteomyelitis, so this needs a same-day assessment rather than a telephone prescription.
Ask about the height and duration of fever, character of the drainage (serous versus purulent), whether erythema is spreading or fluctuant, whether he is using the arm differently, and whether he appears systemically unwell. Arrange a clinic visit and photograph the site.
Management: superficial pin-site infection with serous drainage, no fluctuance, and a well-appearing child is usually treated with an oral antistaphylococcal agent (for example cephalexin, weight-based) plus saline pin-site care and a clean dry dressing, with the pins left in place if the fracture is not yet stable. Purulent drainage, a fluid collection, deep tenderness, systemic symptoms, or a child who looks unwell requires urgent evaluation and imaging, and often pin removal with washout.
Context: at 3 weeks the fracture may not be stable, so pins should not be pulled outside a supervised setting. Give return precautions for fever above 38.5 degrees Celsius, spreading redness, or refusal to use the arm.