What is the diagnosis?

Diaphyseal (midshaft) radius and ulna fracture.

• Pearl: Forearm fractures are relatively common injuries, with diaphyseal radius and ulna (commonly referred to as “both-bone”) fractures representing a unique subtype. They are more common in the pediatric population, representing an estimated 5% of all pediatric fractures and they are increasing in frequency [1,2].

What is the mechanism of injury?

This typically occurs after a high-energy traumatic force such as direct trauma to the forearm, falling from height onto an outstretched hand, or a motor vehicle accident [3]. It is less commonly seen after ground-level falls, usually when there is underlying bone fragility due to pathologic causes such as osteoporosis or cancer [4].

What physical exam findings are expected?

On examination, both bone forearm fractures will typically present with obvious deformity of the forearm. There is increased potential for an open fracture so a close examination of the skin should be performed [5]. Neurovascular deficits are not as common, but a thorough exam should be performed.

• Pearl: Anterior interosseous nerve (AIN), posterior interosseous (PIN) and ulnar nerves should all be tested in the physical exam. Motor testing involves doing the “okay” sign (AIN), “thumbs-up” sign (PIN), and abducting fingers (ulnar nerve) [5].

Which imaging modalities can be used?

Plain orthogonal radiographs of the forearm in AP and lateral views should be obtained. Oblique views and above and below films such as wrist and elbow radiographs can also be considered [3,5].

What is the management in the ED?

These patients should undergo thorough physical exam to assess for open fracture, neurovascular deficits and compartment syndrome. Patents with open fractures should be irrigated with normal saline, receive IV antibiotics, tetanus prophylaxis as indicated, and cover the wound in a sterile dressing [3]. Reduction and provisional stabilization in a sugar-tong splint at neutral is recommended [3,6,7].

• Pearl: Use of finger traps can help reduce significantly displaced fractures. Place the forearm in neutral position with the elbow held in 90 degrees of flexion [6]. 

• Pearl: Both bone fractures are difficult to reduce due to the instability - if attempting a reduction, a splint should be applied concomitantly.

When do you consult Orthopedics?

Consider consulting orthopedics for both-bone forearm fractures, especially in adults. Depending on the fracture pattern, pediatric patients can often be treated nonoperatively, but most adults require open reduction and internal fixation with intramedullary nailing and/or plate fixation [7,8].

• Pearl: Long-term outcomes after this type of injury include grip strength deficits and decreased ROM in supination-pronation (18 degree loss) and wrist flexion-extension (19 degree loss). The outcomes are similar in those who were skeletally immature and mature at the time of injury [9].