A reusable, self-adhesive electrode for intraoperative stimulation in the lower limbs

A suction-based stimulating electrode was designed and fabricated to allow intraoperative testing of lower-limb muscles during routinely scheduled sur gical procedures. The suction device can adhere to a small exposure of musc le surface with reproducible contact forces and can maintain its geometric relationship to the underlying tissue for sufficient time to grade the resu lting muscle contraction before removal and repositioning. When operated wi th a 10-cc syringe, the device can generate between 0 and 23 N of contact f orce; correlation between measured contact forces and those analytically pr edicted was 0.989. Preliminary animal testing indicates that the reusable d evice maintains its position over the nerve entry point even during vigorou s active contractions of the stimulated muscle. Thus, it may be a valuable useful tool for locating the optimal site for a permanent electrode for fun ctional electrical stimulation (FES) applications, as well as an ideal mean s of providing accurate and repeatable stimulation in various locations.