Patent ID: 9241682
Filing Date: 2016-01-26
CPC Classification: A61B

Claim Text:
1. An x-ray calibration apparatus, comprising: a radiolucent knee alignment jig configured to receive a knee of a patient, the knee alignment jig comprising (i) a bottom plate, (ii) a lateral sidewall secured to and extending upwardly from a lateral side of the bottom plate, and (iii) a medial sidewall secured to and extending upwardly from a medial side of the bottom plate, a radiolucent cushion configured to hold a patient's knee at a fixed angle of flexion, the cushion being secured to an upper surface of the bottom plate and positioned between the lateral sidewall and the medial sidewall of the radiolucent knee alignment jig, a first plurality of radio-opaque fiducial markers positioned within the lateral sidewall, comprising (i) an upper lateral plurality of radio-opaque fiducial markers, positioned within the lateral sidewall such that when viewed in an x-ray image taken perpendicularly to the lateral sidewall, each of the upper lateral plurality of radio-opaque fiducial markers appears above an upper ridge of the radiolucent cushion, and (ii) a lower lateral plurality of radio-opaque fiducial markers, positioned within the lateral sidewall such that when viewed in an x-ray image taken perpendicularly to the lateral sidewall, each of the lower lateral plurality of radio-opaque fiducial markers appears below the upper ridge of the radiolucent cushion, and a second plurality of radio-opaque fiducial markers positioned within the medial sidewall, wherein the second plurality of radio-opaque fiducial markers are positioned such that (i) when viewed in an x-ray image taken perpendicularly to the bottom plate, each of the second plurality of radio-opaque fiducial markers are distinct from the first plurality of radio-opaque fiducial markers, and (ii) when viewed in an x-ray image taken perpendicularly to the lateral sidewall, each of the second plurality of radio-opaque fiducial markers are distinct from the first plurality of radio-opaque fiducial markers.