What is the diagnosis?

This is a humeral shaft fracture.

• Pearl: Humeral shaft fractures account for ~1-3% of all adult fractures. 

• Pearl: Injury to the radial nerve is the most common associated nerve injury. The humeral shaft is divided into proximal, middle, or distal, and injury to the radial nerve occurs more commonly in the middle and distal thirds of the shaft [1,2].

What is the mechanism of injury?

This usually occurs via a lower energy mechanism in elderly women, often a fall from standing onto an outstretched arm, or high energy mechanism in younger men [3].

What physical exam findings are expected?

On examination, there will often be a deformity of the upper arm including shortening, pain to touch, and swelling. 

• Pearl: Radial nerve functioning should be tested upon initial evaluation and post-splinting. Radial nerve testing can be done via wrist extension, supination, or finger extension (particularly of the thumb). Patients will often present with wrist drop.

• Pearl: Open Fractures have a higher incidence of radial nerve injury [4].

Which imaging modalities can be used?

Plain radiographs of the humerus should be obtained pre- and post-reduction and splinting. CT exam may be requested or performed to evaluate for occult fracture or for Orthopedics operative planning.

Image 2. Post-reduction and splinting of the right humeral shaft fracture. Author’s own images.

What is the management in the ED?

A coaptation splint extending up to the axilla and over the shoulder or functional bracing of the humeral shaft fracture after attempted reduction is the gold standard if the patient does not meet any exclusion criteria such as an open fracture, neurovascular compromise, or polytrauma.

• Pearl: Remember to perform neurovascular testing pre- and post-splinting, particularly of the radial nerve and brachial artery distribution [5,6]. 

When do you consult Orthopedics?

Orthopedics can be consulted for the splinting and reduction of the humeral fracture (depending on your institution) and should be consulted emergently for open fractures and those with neurovascular compromise [6]. Those without closed fractures and without neurovascular compromise can be followed closely outpatient.