Yes.
Would you know how to describe it? Really describe it.
Thankfully, a patent has done that for you, in gruesome detail.
An implantable penile prosthesis for implanting completely within a patient’s penis comprising at least one elongated member having a flexible distal forward section for implantation within the pendulous penis, said forward section being constructed to rigidize upon being filled with pressuring fluid; a proximal, rearward section adapted to be implanted within the root end of the penis, said rearward section containing a fluid reservoir chamber, externally operable pump means in said member for transferring fluid under pressure to said flexible distal forward section of said member for achieving an erection; and valve means positioned within said member which open when said pump is operated so that fluid is forced from said pump through said valve means into said flexible distal forward section of said chamber.
( Scott v. Finney, 34 F.3d 1058)
How *sexy* is that, huh?