Force and rotation sensing device and method

A method for measuring force within a knee joint, the method comprising:

• setting a reference orientation of a housing against a resected condyle in a knee joint;
• inserting a distal portion of the housing into the knee joint, the distal portion of the housing including a force sensor;
• positioning the knee joint at a plurality of positions between flexion and extension, inclusive;
• at each position of the plurality of positions, reading a measurement of flexion/extension position of the housing from a display on the housing;
• and
• at each position of the plurality of positions, reading a measurement of force exerted by the knee joint on a distal portion of the housing from a display on the housing.

A force and rotation sensing device, comprising:

• an elongate housing extending along a longitudinal axis;
• a force sensor configured to measure a force exerted between opposing surfaces of the housing at a distal portion of the housing;
• a force display positioned on the housing and configured to visually represent a value of the measured force, the force display including a dual-sided light-emitting diode display that is visible from opposing sides of the housing;
• a reference surface positioned on the housing and formed as one of the opposing surfaces, the reference surface defining a plane that includes the longitudinal axis, the reference surface further defining a flexion/extension axis as being parallel to the plane and perpendicular to the longitudinal axis;
• a zero button on the housing, the zero button configured to set a reference orientation of the housing;
• a first rotation sensor configured to measure a flexion/extension position of the housing, the flexion/extension position being a relative rotational position about the flexion/extension axis with respect to the reference orientation, the first rotation sensor including at least one of an accelerometer or a gyroscope;
• a flexion/extension display positioned on a proximal end of the housing, opposite the distal portion, the flexion/extension display configured to visually represent a value of the measured flexion/extension position;
• a second rotation sensor configured to measure a varus/valgus position of the housing, the varus/valgus position being a relative rotational position about the longitudinal axis with respect to the reference orientation, the second rotation sensor including at least one of an accelerometer or a gyroscope;
• a varus/valgus display positioned on the proximal end of the housing, the varus/valgus display configured to visually represent a value of the measured varus/valgus position;
• and
• circuitry configured to wirelessly transmit data corresponding to the value of the measured flexion/extension position and the value of the measured varus/valgus position.