Interferential electrical stimulation for improved bladder management following spinal cord injury.

Patients with spinal cord injury (SCI) with neurogenic bladder (NB) represent a major medical problem, which initiated the search for a non-invasive and effective treatment that is easy to apply and without side effects. A study was performed using interferential medium frequency current electrical stimulation (IMFC ES) on 332 patients shortly after SCI diagnosed with NB dysfunction. All subjects received standard care and patients of the experimental group additionally received IMFC ES. Urinary management results included volitional control of voiding, intermittent catheterization, post-voidance residuum (PVR) quantity and quantity of urine lost (LOSS). Results were assessed based on the American spinal cord injury association impairment scale (AIS). The IMFC ES included two channels of medium frequency stimulation that were marginally different. Within the body, a low frequency field was generated through the interaction of the medium frequencies, which stimulated the urinary structures. In the IMFC ES group, interference stimulation was applied for 10 min with frequencies cycling from 0-100 Hz and back in 10 sec intervals. The strength of the low frequency stimulation, achieved by the interference of the two medium-frequency fields, was adjusted to the patients' vibration sensation. The intensities triggering vibration sensation were between 20-80 mA for patients with AIS levels B, C and D. For patients with AIS level A intensities <20 mA were used for therapeutic effects without causing skin injuries. Safety of IMFC ES was based on occurrence of adverse events of which none were recorded in the experimental group. IMFC ES was effective in patients with AIS levels B and C, significantly decreasing PVR and LOSS compared with patients receiving standard care No significant improvements in urinary management were observed following IMFC ES treatment of patients with AIS level A. Patients with SCI and NB classed as AIS levels B and C that exhibit preserved sensitivity were the best beneficiaries of IMFC ES therapy.