Patent ID: 8657830

Claim:
A pelvic locating frame, adapted to adjustably mount in opposition to an adjustable backrest, and suitable for use in connection with computer assisted surgery for finding the orientation of a patient's pelvic plane, comprising: a support assembly, comprising: at least two anterior superior iliac spine (ASIS) locating features, adapted to press against and superficially engage the patient's ASIS; at least one pubic locating feature, adapted to engage the patient's pubic symphysis, said ASIS and pubic locating features defining an anterior pelvic plane (APP); a group of index features, said group constrained to maintain a predetermined rotational relationship to said anterior pelvic plane (APP) defined by said ASIS and pubic locating features; and a plurality of elongated members to which said at least two ASIS locating features, said at least one pubic locating feature, and said group of index features are mounted; a horizontal adjustment rod distinct from said support assembly to which said support assembly is mounted, said horizontal adjustment rod having an associated first axis along its length; and a vertical adjustment rod distinct from said support assembly to which said horizontal adjustment rod is mounted, said vertical adjustment rod being substantially perpendicular to said horizontal adjustment rod and having an associated second axis along its length, said elongated members arranged such that each can move independently of said vertical adjustment rod, said horizontal and vertical adjustment rods arranged such that said support assembly is capable of being rotated about said first and second axes, said pelvic locating frame arranged such that the position of said second axis does not move when said support assembly is rotated about said first axis, and does not move when said support assembly is rotated about said second axis.