Tissue Response: Muscle : Page 8

Peak force at dislodgement (PFD) during explant for each electrode type. Electrodes were explanted immediately following implant in one group and after periods of one and four hours, one, three and five days, one week, ten days, two and four weeks in others.
The dislodgement force at immediate explant represented the degree of mechanical fixation due to the barb design. The CWRU type had the most compliant barb and the lowest PFD at this time. The NEC electrode fabricated from a hard drawn wire matched the fixation of the Peterson type electrode at immediate explant. The change in PFD at the later implant periods resulted from the change in the amount and properties of the tissues around the electrode coils and barb. In the CWRU, Peterson and Scheiner type of electrodes, the most rapid increase in peak dislodgement force was observed between five and seven days.