A bone cutting system is disclosed that supports one or more bone cuts that are aligned relative to a mechanical axis. The system comprises a first bone cutting jig, a second bone cutting jig, a sensored insert, a bone jig adapter shim, and a device having at least two reference surfaces. The sensored insert includes a three-axis accelerometer to measure position, rotation, and tilt and includes a plurality of sensors to measure a parameter of the muscular-skeletal system. The reference surface device can be an operating table having a first reference surface and a second reference surface that is perpendicular to the first reference surface for referencing the three-axis accelerometer. The bone jig adapter shim can include a tab that fits into a slot of the first or second bone cutting jigs. A remote system receives accelerometer data to calculate offset relative to a mechanical axis.
