Author: Ruikang (Kong Kong) Liu, MD
Co Author #1: Jessica Butts, MD
Senior Editor: Kristine Karlson, MD, FAMSSM
Editor: Drew Duerson, MD

Patient Presentation:
15yoM football player with L arm weakness.

History:
One-month prior to presentation he was hit on the facemask with forced left lateral neck rotation. He described a burning and tingling sensation along his left neck down the arm lasting less than one minute. He reported decreased strength and function of his left arm with weight lifting, but he was able to do activities of daily living so did not tell anyone of this injury. Then one week prior he saw a chiropractor, with improvement in his neck spasm and soreness but the arm weakness persisted. Finally, three days prior he was hit again in football with a forced left lateral neck rotation. He again described the same transient burning and tingling down the left anterior neck but now has worsened persistent left arm weakness.

Physical Exam:
Inspection: Well-defined musculature of trapezius, upper back, shoulders, and chest. Subtle loss of the sharp definition of left trapezius and periscapular muscles, concerning for early atrophy.

ROM: Full active and passive range of motion of neck and shoulders in all directions.

Right arm: 5/5 strength throughout.

Left arm:
-Shoulder: 4/5 abduction, 3+/5 forward elevation, 3+/5 external rotation, 4/5 internal rotation.
-4/5 biceps and triceps.
-5/5 wrist extension/flexion, interosseous muscles, finger extension, grip equal/symmetric.

Negative Spurling's maneuver. Negative provocative rotator cuff testing including no pain or weakness with Jobe’s, resisted external rotation, or lift off tests. No sensory deficits.

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