Cramp,fasciculation syndrome

A treatable hyperexcitable peripheral nerve disorder

Tahmoush, A. J. MD
Alonso, R. J. MD
Tahmoush, G. P.
Heiman-Patterson, T. D. MD

Department of Neurology (Drs. A.J. Tahmoush and T.D. Heiman-Patterson), Thomas Jefferson University, Philadelphia, PA, and the Department of Neurology (Dr. R.J. Alonso), Indiana University, Indianapolis, IN.

Address correspondence and reprint requests to Dr. Albert J. Tahmoush, Jefferson Medical College, 111 South 11th Street, Suite 9606, Philadelphia, PA 19107.

Received June 4, 1990. Accepted for publication in final form December 21, 1990.

Neurology 41(7):p 1021-1024, July 1991.

Article abstract

We report nine patients with muscle aching, cramps, stiffness, exercise intolerance, and peripheral nerve hyperexcitability. Neurologic examination showed calf fasciculations in seven, quadriceps myokymia in two, and deltoid myokymia in one patient. Two patients had mild increase in serum creatine kinase. Muscle biopsy showed either no abnormality (three patients) or mild neurogenic changes (four patients). Fasciculations were the only abnormality on routine electrodiagnostic studies. Supramaximal stimulation of the median, ulnar, peroneal, and posterior tibial nerves at frequencies of 0.5, 1,2, and 5 Hz produced showers of electrical potentials following the M response in at least one nerve. In three patients, the fasciculations and evoked electrical potentials were abolished by regional application of curare but not nerve block. Carbamazepine therapy caused moderate-to-marked reduction of symptoms and nerve hyperexcitability. We designate this hyperexcitable peripheral nerve disorder as the “cramp-fasciculation syndrome.”