Indications

PITFALLS

• Distal radioulnar joint (DRUJ) instability is associated with the location of the radial shaft fracture: 55% of isolated radial shaft fractures located within 7.5 cm from the midarticular surface of the radius were associated with DRUJ instability, whereas only 6% of fractures located beyond 7.5 cm from the midarticular surface of the radius were associated with DRUJ instability.

• Proximal-third ulnar shaft fractures are often associated with posterior radial head dislocation or radial head fracture. Proper clinical and radiologic examination of the radiocapitallar joint is necessary with these injuries.

Forearm fractures of both bones in an adult

Isolated radial shaft fractures

Proximal-third ulnar shaft fractures

Displaced distal two-thirds ulnar shaft fractures with greater than 10° of angulation or less than 50% opposition

Open radius or ulnar shaft fractures

Examination/Imaging

Examination of the skin for open lacerations

Palpation of the radial and ulnar arteries

Examination of motor and sensory function of the median, ulnar, and radial nerves

Anteroposterior (AP) and lateral radiographs of the forearm. Figure 1 shows orthogonal radiographs of combined radial and ulnar shaft fractures.

Dedicated wrist and elbow radiographs of the affected arm

FIGURE 1

Surgical Anatomy

Volar anatomy of the radius

• Superficial layer: brachioradialis muscle, flexor carpi radialis muscle, superficial branch of the radial nerve, radial artery

♦ Figure 2 shows the superficial layer of the volar forearm; note the interval between the brachioradialis (radial side) and the pronator teres/flexor carpi radialis (ulnar side).

♦ Figure 3 shows a view of the volar forearm with the brachioradialis and flexor carpi radialis cut away. Note the position of the radial artery and the superficial branch of the radial nerve.

• Deep layer

♦ Figure 4 shows the deep layer of the volar forearm. Note the insertion of the pronator quadratus on the distal third, the flexor pollicis longus and flexor digitorum superficialis on the middle third, and the pronator teres and supinator on the proximal third of the radius.

♦ Proximal third of radius: supinator muscle, posterior interosseous nerve (see Fig. 4)

♦ Middle third of radius: pronator teres muscle, flexor pollicis longus muscle, flexor digitorum superficialis muscle (see Fig. 4)

♦ Distal third of radius: pronator quadratus muscle (see Fig. 4)