Fractures of the radius and ulna are the most common fractures of the upper extremity, with distal fractures occurring more often than proximal fractures.^1–3 The rate of distal radius fractures is highest (nearly double) in people younger than 18 years and older than 65 years.¹

The most common mechanism of injury for radius and ulna fractures is sudden axial loading onto the radius/ulna, often from a fall onto an outstretched hand with wrist extension.^1,2 Although nondisplaced, or minimally displaced, fractures of the radius and ulna usually can be managed by family physicians, it is important to identify fractures that require referral to an orthopedist. The most common radius and ulna fractures, with a summary of their management and indications for referral, are shown in Table 1.^2,4–11

Most fractures of the radius or ulna seen by family physicians are distal radius, midshaft, or radial head fractures. Other fractures, such as proximal ulna fractures of the coronoid and olecranon, are less common and therefore not addressed in this article. Application of the various splints and casts discussed in this article was detailed previously in American Family Physician.¹²

Initial Evaluation

Patients with radius or ulna fractures often present with reduced range of motion in the joint adjacent to the fracture (i.e., wrist for distal fracture and elbow for proximal fracture).^2,3,9 Among the examination findings that suggest a wrist fracture, painful dorsiflexion is the most sensitive (95.7%) and ecchymosis is the most specific (97.8%).¹³ Additional predictors of a distal fracture include wrist edema, deformity, and pain with forearm pronation.¹³ Proximal fractures often cause limited forearm pronation or supination and limited elbow flexion or extension.

Although initial studies of the elbow extension test (ability to fully extend the elbow) for ruling out elbow fractures were promising, more recent studies have not demonstrated high accuracy, even with concurrent focal tenderness.¹⁴

However, when evaluating patients for suspected proximal radius or ulna fractures, physical examination should include assessment for ulnar and radial collateral ligamentous injury using elbow varus and valgus stress testing¹⁴ (see https://www.youtube.com/watch?v=bCqPTSgW3-c). In addition, patients with a suspected fracture should be evaluated for neurovascular compromise or skin puncture, which require urgent orthopedic consultation.^2,3,9

Imaging

There are no well-validated clinical prediction rules to help guide when to use radiography for suspected radius and ulna fractures, as with other fractures (e.g., the Ottawa rules for ankle fractures). In most cases, radiography is performed when fractures of the radius or ulna are suspected based on presentation and physical examination findings.

A two-view (posteroanterior and lateral) radiograph is generally sufficient for forearm fractures; however, a third (oblique) view should be obtained for suspected wrist or elbow fractures to assess the extent, angulation, and displacement of the fracture.^2,3,9 If initial radiograph findings are negative but fracture is still suspected (e.g., there is pain, tenderness, or weakness), splinting and follow-up imaging in seven to 14 days are warranted.

Ultrasonography is an alternative to radiography for detection of forearm fractures, with a sensitivity of 97% and specificity of 95%.¹⁵ Ultrasonography can be performed at the point of care, costs less than radiography, and avoids radiation exposure. However, availability, technician expertise, and lack of patient cooperation with the imaging procedure may limit its use. Radiography and ultrasonography can detect pathognomonic features of injury, such as the presence of a posterior and elevated anterior elbow fat pad (sail sign) associated with proximal radius and ulna fractures (Figure 1).