JM Pardal Fernandez, JL Beato-Perez, E Lozano-Setien, I Iniesta-Lopez
A 47-year-old white male with a background history of chronic left sciatic pain developeda lump on the left thigh. Muscle MRI showed changes consistent with myotomeL5 hypertrophy, while a lumbosacral MRI showed a disc protrusion at L4-L5. Continuouscomplex repetitive discharges became evident through needle electromyogramwith a muscle biopsy showing chronic denervation changes. Botulinum toxin (BT) administered for a year produced a significant electrophysiological improvement.This is a rare case of BT responsive L5 radicular denervation hypertrophy involvingthe muscle tensor fascia lata.