Stiff-man syndrome: case report.

Stiff-man syndrome is a rare neurologic disorder characterized by progressive, fluctuating muscle rigidity with painful muscle contractions affecting predominantly the back and proximal extremities. In the ED, the diagnosis can be easily overlooked and misdiagnosed as acute or chronic low back pain and muscle spasm. This syndrome is often associated with diabetes, autoimmune diseases, and cancer. This report describes an illustrative case of a 39-year-old woman who presented to the ED with a two-year history of right leg spasms and low back pain that had become so severe in the preceding two days that she was unable to ambulate. Clues to the patient's proper diagnosis coincide with the diagnostic criteria for stiff-man syndrome: the presence of a slowly progressive stiffness of the axial muscles and proximal limb muscles, making ambulation difficult; hyperlordosis of the lumbar spine; episodic spasms precipitated by jarring or sudden movement; a normal intellectual, sensory, and motor examination when not in spasm; and a marked amelioration of symptoms with the IV administration of diazepam. High-dose oral diazepam is the maintenance drug of choice.