Patent ID: 7914532

Claim:
A method of installation of a rod member in a bone, comprising: placing a rod member along a medullary canal of a bone, the rod member defining one or more transverse apertures, at least one of the transverse apertures being a locking aperture having opposing ends and including at least two internal threads following distinct helical paths centered about a same axis, each internal thread having a distinct thread lead disposed adjacent a same opposing end of the locking aperture; and attaching the rod member to the bone with a fastener (a) capable of alternative threaded engagement with each of the internal threads of the locking aperture and (b) disposed in threaded engagement with only one of the internal threads, to lock the fastener to the rod member, wherein the fastener includes a head and a shank, wherein the shank has a single external thread formed on leading, central, and trailing portions of the shank, wherein the single external thread has a substantially uniform pitch and is substantially deeper than each of the internal threads, and wherein the step of attaching results in the single external thread being in threaded engagement with a thread of about a same depth formed in bone adjacent the opposing ends of the locking aperture and in threaded engagement with an internal thread of the locking aperture.