The Journal of Bone and Joint Surgery

Image Quiz

An Uncommon Complication of an Injury to the Shoulder¹
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Answer: Avascular necrosis of the humeral head

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Fig. 2: Anteroposterior radiograph of the right shoulder, made seven months after the injury, showing a subchondral fracture (arrow) of the humeral head indicative of avascular necrosis.

Fig. 3: Magnetic resonance imaging of the right shoulder confirmed the diagnosis of avascular necrosis. Note the well demarcated band of low signal intensity (arrows) surrounding a region of normal bone marrow in the humeral head.

Discussion

Several large series of fractures of the proximal humeral physis have been reported, but avascular necrosis of the humeral head has not been noted as a complication in any of them^2-4.

Complications of these fractures, although rare, include malunion, humeral shortening, varus angulation, valgus angulation, and restricted motion of the shoulder⁵. Neurovascular injury can also occur⁶.

Arterial injection studies of the humeral head have shown that the anterolateral ascending branch of the anterior humeral circumflex artery provides the most important blood supply to the head of the humerus⁷. We speculate that this vessel, or one of its major branches, was injured in our patient.

References:

1. Martin RP, Parsons DL. Avascular necrosis of the proximal humeral epiphysis after physeal fractures. A case report. J Bone Joint Surg Am. 1997;79:760-2.
2. Baxter MP, Wiley JJ. Fractures of the proximal humeral epiphysis. Their influence on humeral growth. J Bone Joint Surg Br. 1986;68:570-3.
3. Dameron TB Jr, Reibel DB. Fractures involving the proximal humeral epiphyseal plate. J Bone Joint Surg Am. 1969;51:289-97.
4. Fraser RL, Haliburton RA, Barber JR. Displaced epiphyseal fractures of the proximal humerus. Can J Surg. 1967;10:427-30.
5. Curtis RJ Jr, Rockwood CA Jr. Fractures and dislocations of the shoulder in children. In: Rockwood CA Jr, Matsen FA III, editors. The shoulder. Volume 2. Philadelphia: WB Saunders; 1990. p 991-1002.
6. Sullivan CA, Burman JA. Blunt axillary artery injury in children: case reports. Vasc Surg. 1988;22:60-5.
7. Gerber C, Schneeberger AG, Vinh T-S. The arterial vascularization of the humeral head. An anatomical study. J Bone Joint Surg Am. 1990;72:1486-94.