Pediatric brachial artery injury due to supracondylar humerus fractures: A case series

Introduction

Supracondylar humerus fractures make up 60–70% of pediatric elbow fractures.^1,2 Two to 20% present with abnormal vascular examinations ranging from ischemic hands to warm, well-perfused hands without palpable radial pulses, known as pink or perfused pulseless hands (PPH).^1–5 For ischemia, brachial artery exploration is mandatory. For PPH, there is no clear consensus on operative management given the high propensity for arterial vasospasm in children and profuse collateralization. However, long-term complications can occur if reversible injuries are not repaired.

Report of cases

Four patients presented with PPH with absent pulses, but intact Doppler signals. Two of these patients were discharged following reduction of the fracture and returned one to three days later with pain and evidence of compartment syndrome. Surgical exploration revealed a tethered artery between fracture fragments. This was released along with the compartments with return of normal function. Mild motor defect and slight contracture of two fingers at one-year follow-up was noted in one child.

Two other children with PPH who were admitted for observation progressed to acute ischemia. Duplex ultrasound revealed brachial artery occlusion, and surgical exploration revealed a transected brachial artery requiring thrombectomy and a basilic vein interposition graft. The other was found to have a large hematoma requiring decompression of the artery with restoration of normal function in both patients.

The fifth child presented with an acutely ischemic hand secondary to a thrombosed tethered artery. Thrombectomy after release of the artery restored normal function.

Discussion

For the PPH associated with supracondylar humerus fracture, the first step in management is prompt fracture reduction and percutaneous pinning by orthopedic surgery (see Figure 1). Post-reduction ischemia mandates immediate exploration, but 53–83% of patients have return of palpable pulses, most within a few hours and some months later.^1–5 Although there is no consensus on management after return of palpable pulses, all patients require close monitoring for delayed ischemia and compartment syndrome and are inappropriate for same-day discharge. ⁶ Observation mandates frequent assessment of pulse and Doppler signal, capillary refill, hand temperature, pallor, increasing pain, compartment status, and nerve function with comparison to the contralateral side.^1,3,7 Many studies recommend monitoring for at least 24 h and longer with traction neuropraxia, given the association between nerve and arterial injury.^1,7

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Figure 1.

Management of pediatric upper extremity arterial injury.

For persistent PPH after reduction, the decision lies between non-operative management and immediate surgical exploration. This is challenging given the tendency for small pediatric vessels to spasm and mimic actual injury, the risks of general anesthesia and surgery, and conflicting functional complication rates reported for non-operative cases. We recommend considering Doppler signal status, symptom progression, and duplex imaging to guide decision-making.

When Doppler signals are present, observation is required. Monitoring is essential for early diagnosis of delayed ischemia or compartment syndrome. Younger children are at higher risk for delayed diagnosis due to unreliable exams and inability to communicate symptoms. Close watch for the three A’s of compartment syndrome (anxiety, agitation, and increasing analgesia) can help. ⁸ Children with multiple fractures in the same limb, signs of significant swelling or displacement, neurologic deficits, and injury-to-reduction time greater than 6 h should be considered at higher risk for compartment syndrome.^1,8 Lack of Doppler signals should prompt immediate surgical exploration given associated high rates of reversible arterial injury, as seen in three of our five cases and up to 82% in reports in the literature.^1,9 In our series, duplex ultrasound was reliable for suggesting arterial compromise with all explorations identifying actual reversible injury. A series of 98 patients found 70% of explored PPH had documented brachial injury. ⁹ Duplex ultrasound imaging for brachial artery injury is a simple, non-invasive, readily available, and highly reliable exam to guide surgical exploration.

Immediate surgical intervention affords a prompt diagnosis, definitive management, and avoids complications due to unidentified arterial injury. Injuries include kinked, stretched, tethered, or entrapped artery in the fracture site, intimal tears, thrombosis, traumatic aneurysm with thrombus, and partial or complete transection with collateral flow around the elbow that allows continued perfusion of the hand.^3,9 While pediatric arteries are prone to spasm, it should not be presumed to be the cause of persistent PPH. Vasospasm should resolve within minutes of releasing the external stimulus and has been found in only 9 to 26% of intraoperative cases.^8,9

If true arterial injury is not repaired, this could lead to cold intolerance, delayed thrombosis, neuropathy, pseudoaneurysms, growth retardation with limb length discrepancy, and ischemic contracture.^1–2 Blakely et al. describe 22 children who presented with ischemic contracture as delayed referrals for PPH managed non-operatively. Twelve (52%) underwent delayed exploration finding entrapped arteries and all had return of pulsatile flow after decompression. This underscores that while overall complication rates are low, they are due to delayed surgical intervention of reversible injury when they develop. ¹⁰

There is no consensus for the management of PPH after fracture reduction due to a lack of high-quality, adequately powered studies. The American Academy of Orthopedic Surgeons makes management recommendations regarding appropriate use criteria for supracondylar humerus fractures with vascular injury.^6,7 We recommend additionally the use of duplex imaging of the brachial artery as a guide to therapy.