Transcutaneous Tibial Nerve Stimulation for Spinal Cord Injury Neurogenic Bladder

Electrodes 2 inch by 2 inch will be placed according to anatomic landmarks, with the negative electrode behind the internal malleolus and the positive electrode 10cm superior to the negative electrode, verified with rhythmic flexion of the toes secondary to stimulation of the flexor digitorum and hallicus brevis. The intensity level will be set to the amperage immediately under the threshold for motor contraction. If there is no contraction seen, patients will be excluded. In addition, if the patient perceives pain, the intensity will be lowered until comfortable. Stimulation frequency of 20 Hz and pulse width of 200ms in continuous mode will be used.

Toe flexion will be attempted, as in the TTNS protocol. Then the stimulation will be reduced to 1 mA for 30 minutes. This will continue at 5x weekly until 1-year post-injury.

At the 4 month CMG, subjects initially randomized into the variable dose protocol of 2 x weekly will start doing so for the remainder of the study.