A pelvic implant assembly and associated methods. The confining element preferably includes elongate members running axially along the sheath, which compress the sheath and the stent to reduce hoop stress in the system without promoting undesired adhesion between layers of the sheath. The demultiplexer produces adaptation layer data units, which are processed by the adaptation layer to produce an application layer bitstream. In various embodiments, reflective layers are deposited within and over the channel to form the optical path. An insulating film is provided to electrically insulate the end portions of signal electrodes drawn outside pixel regions.