The most common rapid repetitive stimulation studies are recorded from the Median (APB) or Ulnar (ADM) motor nerves.  However, rapid repetitive stimulation studies can be performed on any motor nerve.

After performing the routine motor nerve conduction study distally, Postexercise motor responses evaluations are performed before considering rapid repetitive stimulation.  The following procedure should be used (this could be done on any motor nerve):

1.    Obtain a supramaximal distal motor response.

2.    Exercise the recording muscle for 10 seconds.

3.    Repeat a single stimulation at the same site with the same current.

4.    An increment of more than 50 – 100% is a positive finding.

Consider performing (for confirmation) with the physician a rapid tetanic stimulation.  Obtain a supramaximal distal motor response from the median or ulnar nerves.  Change the settings of the repetitive stimulations into 30 or 50 Hz and the number of stimuli to 200.  Stabilize the hand and wrist (with two hands (or a board) and explain to the patient that this very painful but brief.  Stimulate the train once.  An increment of more than 50 – 100% is a positive finding.