Over-exertion (Not Elsewhere Classified)
EE was on elevated platform erecting equipment; reached back with left arm (fully extended) to guide/pull scissor lift to platform; felt a ""pop"" and left arm went temporarily numb with tingling in fingertips of 4th and 5th fingers; took a break but declined offer to come down; attempted to ""work out"" discomfort; later, left arm ""went out"" and miner requested assistance.