Backpack Paralysis - A Report of 3 Cases -

J Korean Assoc EMG Electrodiagn Med 2002;4(2):88-92.
Published online May 10, 2002.

Abstract

Upper extremity numbness, weakness and atrophy associated with the use of a heavy backpack have been reported in military personnel and termed pack palsy. The following characteristics should lead one to suspect this diagnosis. A previously well individual who has used a pack for hours first complains of pain or sensory symptoms in the shoulder or arm. The pain is frequently followed by gradual weakness and atrophy mainly in the shoulder girdle. Physical examination will reveal decreased strength in the deltoid, supraspinatous, infraspinatous and, occasionally, in the wrist extensors. Sensory loss may be present but is less common than the motor weakness. Compression of the upper trunk of the brachial plexus or peripheral nerve supply to the shoulder girdle by backpack straps is implicated as the causative mechanism. But many mechanisms and electrodiagnostic findings are proposed. We report 3 cases of backpack paralysis with history, physical examination and electrodiagnostic study.

Key Words: Backpack paralysis, Brachial plexus injury