Bone cutting method for alignment relative to a mechanical axis

A method of bone preparation for a prosthetic joint comprising the steps of:

• coupling a bone cutting jig to a bone;
• coupling a shim to a sensored insert;
• coupling a tab of the shim into a slot of the bone cutting jig where the sensored insert is configured to measure alignment relative to a mechanical axis and where the sensored insert includes a three-axis accelerometer;
• positioning a joint to a target flexion value as measured by the three-axis accelerometer of the sensored insert;
• rotating the joint between a first point and a second point where the first and second points are on opposing sides of the joint;
• monitoring rotation of the joint on a remote system where the sensored insert transmits three-axis accelerometer data to the remote system;
• calculating alignment of the first bone relative to the mechanical axis from quantitative measurement data from the three-axis accelerometer;
• and
• positioning the bone cutting jig such that the bone is cut at a predetermined angle relative to the mechanical axis.

A method of bone preparation for a prosthetic knee joint comprising the steps of:

• coupling a first bone cutting jig to a tibia;
• coupling a sensored insert to the first bone cutting jig where the sensored insert is configured to measure load and position of load and where the sensored insert includes a three-axis accelerometer;
• positioning a knee joint to a target flexion value as measured by the three-axis accelerometer of the sensored insert;
• rotating the knee joint between a first point and a second point where the first and second points are on opposing sides of the knee joint;
• monitoring rotation of the knee joint on a remote system where the sensored insert transmits three-axis accelerometer data to the remote system;
• calculating alignment of the tibia relative to the mechanical axis using at least one of position, rotation, and tilt data from the three-axis accelerometer;
• and
• positioning the first bone cutting jig such that the tibia is cut at a predetermined angle relative to the mechanical axis.