Larry Mellick, MD, MS, FAAP, FACEP
Professor of Emergency Medicine
Medical College of Georgia
Cline Jackson, MD
Emergency Medicine Physician
Cartersville Medical Center
Pearl: Brachial plexus injuries are common and should not be confused with a central nervous injury or vascular accident.
Case One: A 13-year-old male presents to the pediatric emergency department complaining of one week of numbness of his right upper extremity. The patient reports that one week prior to his visit, he boxed with a friend and immediately afterward lifted weights. The numbness began after these activities. While the patient denies any weakness, the examination of this right-hand dominant patient demonstrates a subtle strength difference, with the right upper extremity slightly weaker than the left (although the strength in both extremities was rated 5/5). The sensory examination is significant for numbness of all dermatomes except for C5. A subsequent examination by a neurology resident for sharp and dull sensation produces blood without the patient flinching. There is no pain in the cervical region, and the patient has full range of motion of his neck without associated discomfort. A cervical spine series is normal.
Case Two: A 16-year-old male football player is brought to the emergency department after an injury sustained during this afternoon’s practice. According to the patient, he and another teammate were involved in a tackling drill. On impact, he felt a searing pain in his left shoulder and neck where he struck the other player. He reported a tingling sensation in his left upper extremity and transient weakness, which resolved after about 15 minutes. Since the injury occurred at the end of practice, he did not continue training activities after the event. The boy’s mother, who accompanied him to the emergency department, demands x-rays and asks if he is O.K. to return to practice.
Diagnosis: A brachial plexus injury commonly called a “stinger” or “burner.”
Discussion: These patients are suffering from an acute brachial plexus injury, also known commonly as a “stinger” or “burner.” According to a recent survey of Division III athletes, this common injury occurs in more than 50% of those who play college football at one time or another in their careers. The recurrence rate is equally high.1 The majority of these injuries go untreated, with little or no medical attention sought.
The mechanism of injury is generally that described above, including nerve compression by hyperextension of the neck and rotation toward the affected side, traction of the neck laterally away from the affected side, and impact or compression directly over Erb’s point.1,2 Erb’s point is located at the angle of the clavicle and sternocleidomastoid muscles in the neck and is at the level of C6.( See Figure 1.) The injury involves the nerve roots of C4-C8. (C4 innervates the superior shoulder; C5 the deltoid, shoulder abduction, and lateral upper arm/distal radius; C6 involves the biceps, rotator cuff, and thumb; C7 has the triceps and index and middle fingers; C8 performs finger extension for the 4th and 5th fingers.)
Initial symptoms normally include parasthesia or a burning sensation in the neck along with weakness on the ipsilateral side. These symptoms commonly resolve over a matter of seconds to minutes, but have been reported to persist for as long as 2 weeks. The initial evaluation should include a complete neurologic examination. An assessment of the cervical spinal cord should be accomplished as well as a mental status examination (acknowledging the possibility of an associated closed head injury). The cranial nerves, grip strength, cervical nerve function, and Spurling’s test are recommended examination components. Spurling’s test is performed by placing the patient’s head in extension while it is rotated toward the affected shoulder and an axial load is placed on the head. This maneuver should reproduce the shoulder pain and symptoms previously described. Bilateral weakness is a red flag that should prompt further evaluation. X-rays or MRI may be considered if the mechanism of injury or diagnosis is in doubt. When the associated mechanism is a motor vehicle accident, one should be on the look out for major vascular or thoracic injuries.3 Important historical items to garner are loss of consciousness, mechanism of injury, duration of symptoms, and description of any other motor deficits.
Injuries to the brachial plexus have been classified as mild, moderate, or severe. The most common brachial plexus injuries are mild (grade I injuries), and symptoms and signs generally resolve within minutes to hours. This grade of injury is a neuropraxia of the brachial plexus, and complete recovery is the rule. When the injury is more severe it is labeled moderate (grade II injuries). The outcome of these injuries is thought to result from nerve fiber axonotmesis. In reality, the presentation is almost identical to the milder plexopathy, but with grade II injuries recovery is longer. Weakness, particularly of the deltoid and biceps may persist for 4 to 6 weeks even though sensation may quickly return to normal. For some athletes, full strength does not return for up to six months and may involve neurotmesis of nerve fibers (both the nerve sheath and nerve are injured). Weakness persisting beyond six months is considered a grade III injury.4 Additionally, the diagnoses of acromioclavicular separation, shoulder dislocation, thoracic outlet syndrome, cervical spine injury, and radiculopathy should all be considered when evaluating these patients.
Treatment generally is mild and usually begins with early mobilization of the joint, active stretching exercises, and strength training of the affected shoulder and neck.2 Applying ice to the injured area and using nonsteroidal anti-inflammatory drugs are the initial phase of treatment. Opioids may be added briefly for acute pain control. Injury prevention is best accomplished by ensuring appropriate technique, in tackling especially, as well as checking all equipment to confirm proper fit and protection. A “cowboy collar” or other protective devices may be considered if the risk of re-injury is high.5
From the perspective of the emergency medicine physician, follow-up, further rehabilitation, and the return to play decision should reside with the patient’s primary care provider or a sports medicine physician.