Patent ID: 7753866

Claim:
A flexion control ankle joint apparatus, comprising: 1) a proximal plate having an upper end and a lower end; 2) a distal plate coupled to the proximal plate through a spherical dome coupling, said spherical dome coupling comprising: a) a spherical dome; b) a mating cavity surface, said mating cavity surface in contact with said spherical dome, said mating cavity surface having a through hole; said spherical dome presenting a spherical surface for contacting said mating cavity surface, said spherical surface consisting of a portion of a hemisphere less than a full hemisphere; c) a captive pin attached to said spherical dome, said captive pin having a shank portion passing through said through hole in said mating cavity surface, said captive pin having an enlarged portion incapable of passing through said through hole in said mating cavity surface; and d) a spring for providing a preload force to hold said spherical dome and said proximal plate in contact; and 3) a range limiting system, comprising: a) a tongue connected to the lower end of the proximal plate; b) two tongue-stops connected to the distal plate at a generally perpendicular orientation, wherein each of the tongue-stops includes a threaded hole through which a threaded rod is connected to the tongue-stops in threaded engagement.