Method and apparatus for performing an open wedge, high tibial osteotomy

A method for performing an open wedge, high tibial osteotomy, the method comprising:

• providing:
• an adjustable base assembly, the adjustable base assembly comprising:
• a base;
• an anterior arm attached to the base;
• a first opening extending through the anterior arm and the base for receiving a frontal fixation pin for pivotally mounting the adjustable base assembly to a tibia;
• a hinge pin slider slidably mounted to the anterior arm for selective disposition along the anterior arm, the hinge pin slider including a hinge pin aimer for receiving a hinge pin;
• and
• a second opening extending through the base for receiving an antero-medial fixation pin for pinning the base to the tibia;
• a keyhole drill guide assembly for mounting to the base of the adjustable base assembly, the keyhole drill guide comprising:
• at least one keyhole drill guide;
• a medial locator tab;
• and
• an antero-medial locator tab;
• a biplanar alignment assembly for mounting to the adjustable base assembly, the biplanar alignment assembly comprising a biplanar alignment bar formed at least in part out of a radio-opaque material;
• a hinge pin for deployment through the hinge pin aimer and into the tibia;
• a cutting guide for mounting to the base of the adjustable base assembly, the cutting guide comprising:
• at least one keyhole locating boss;
• and
• a saw guide slot;
• and
• an implant for disposition in the wedge-like opening in the bone;
• mounting the keyhole drill guide assembly to the base of the adjustable base assembly and mounting the biplanar alignment assembly to the base of the adjustable base assembly;
• positioning the antero-medial locating tab against the medial aspect of the tibia, positioning the medial locating tab against the medial aspect of the tibia and, when viewing from the lateral view, aligning the biplanar alignment bar with the tibial plateau;
• pivotally mounting the adjustable base assembly to the tibia with a frontal fixation pin;
• rotating the anterior arm of the adjustable base assembly about the frontal fixation pin, and adjusting the position of hinge pin slider on the anterior arm, so as to align the hinge pin aimer with a desired position for the hinge pin;
• passing the hinge pin through the hinge pin aimer and into the tibia;
• drilling at least one keyhole in the tibia using the keyhole drill guide assembly;
• replacing the keyhole drill guide assembly with the cutting guide;
• forming a saw cut in the tibia using the cutting guide;
• opening the saw cut so as to form a wedge-like opening in the bone;
• and
• inserting the implant into the wedge-like opening in the bone.