Posterior Arm Compartment Syndrome After a Combined Supracondylar Humeral and Capitellar Fractures in an Adolescent

Abstract

Supracondylar humeral fractures in children are common, with associated bony injuries typically being fractures of the forearm or distal radius. To our knowledge, a combined supracondylar humeral fracture associated with a Hahn-Steinthal capitellar fracture has not been reported earlier. Similarly, posterior arm compartment syndrome is extremely rare, with most instances having occurred after chronic compression and bleeding into the compartments from anticoagulation, direct trauma including crush, or tendon ruptures. Only 2 cases have been reported after a fracture of the humerus. One of these described fractures was localized to a distal shaft and the other involved the surgical neck. No cases have been reported in children, nor have any been reported after a supracondylar humeral fracture. In this case report, we describe a patient who presented with an ipsilateral Wilkins type-3A supracondylar humeral fracture, Hahn-Steinthal capitellar fracture, Salter-Harris II distal radius fracture, and posterior arm compartment syndrome. The patient was taken to the operative room for closed reduction and percutaneous pinning of the radius fracture with open reduction, internal fixation of the distal humeral fractures. Elevated compartment pressure measurements were anticipated because of the nature of the injuries. After fixation of the fractures, the mobile wad, volar, and dorsal compartments measured 9, 9, and 8 mm Hg, respectively. The absolute pressure in the posterior arm compartment was measured multiple times in different locations ranging from 34 to 39 mm Hg. The patient's blood pressure throughout the case averaged 115/65 mm Hg. A diagnosis of posterior arm compartment syndrome was confirmed and the fascia was released. Our patient ultimately suffered 2 uncommon injuries involving the arm. She sustained a complex fracture of the distal humerus with an extension type supracondylar fracture, a separate Hahn-Steinthal capitellar fracture, and isolated posterior arm compartment syndrome. This is an unusual case that required specialized care and follow-up. Level IV.