A 34-year-old man is brought to the emergency department after being involved in a motor vehicle collision. He was a restrained driver and used his arm to brace the impact. The patient has severe pain in his right arm. Vital signs are within normal limits. Examination shows a deformed right upper arm that appears shorter than the left. The midportion of the right arm is swollen and tender. He has limited extension at the wrist joint and decreased sensation over the dorsoradial aspect of the right hand. Radial pulse is 1+ on the right and 2+ on the left. An x-ray of the arm shows an oblique fracture of the midshaft of the right humerus. Which of the following is the best next step in management of this patient?

Question

A 34-year-old man is brought to the emergency department after being involved in a motor vehicle collision.  He was a restrained driver and used his arm to brace the impact.  The patient has severe pain in his right arm.  Vital signs are within normal limits.  Examination shows a deformed right upper arm that appears shorter than the left.  The midportion of the right arm is swollen and tender.  He has limited extension at the wrist joint and decreased sensation over the dorsoradial aspect of the right hand.  Radial pulse is 1+ on the right and 2+ on the left.  An x-ray of the arm shows an oblique fracture of the midshaft of the right humerus.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

This patient with arm pain, deformity, and swelling and evidence of radial nerve injury (eg, limited extension at wrist joint) has a midshaft humeral fracture, confirmed by x-ray. Fractures of the humeral shaft are generally seen following a direct blow to the arm, a fall, an automobile injury, or a crushing injury. The radial nerve is commonly stretched in such fractures, leading to limited wrist extension and associated sensory deficits, as seen in this patient; however, most cases represent neurapraxia that resolves after management of the fracture. Although most cases of isolated diaphyseal (midshaft) humeral fracture can be treated nonsurgically (eg, closed reduction followed by arm immobilization with a coaptation or sugar-tong splint), open reduction and surgical exploration are indicated with open fractures, significant displacement (eg, arm shortening, as in this patient), neurovascular compromise (eg, asymmetric radial pulses, as in this patient), polytrauma, and pathologic fractures. (Choices A and C) A neutral wrist splint alone might help this patient's radial nerve symptoms but would not provide definitive management of the fracture. A long arm hanging cast (with the cast hung from the neck and the elbow flexed at 90 degrees) can be used in some cases of midshaft humeral fracture, but this patient's neurovascular compromise is an indication for open reduction and surgical exploration. (Choice B) Although an electromyogram (EMG) can evaluate nerve injuries, radial nerve neurapraxia due to midshaft humeral fracture resolves in up to 90% of cases, including with nonsurgical management. EMG can be considered if radial nerve function does not recover following surgery. (Choice E) External fixation (eg, with external pins) is used in cases of polytrauma; severe, comminuted open fractures with defects in skin, bone, or soft tissue; and some burn-related injuries. Educational objective: Midshaft humeral fractures occur due to direct blows to the arm and can cause pain, swelling, deformity, and shortening. Associated radial nerve neurapraxia is common and often resolves with appropriate management of the fracture. Many midshaft humeral fractures can be treated nonsurgically. Indications for open reduction and surgical exploration include open fractures, neurovascular compromise, and significant displacement.

A 34-Year-Old Man Is Brought to the Emergency Department After