A surgical equipment kit for a knee replacement or revision procedure comprising: a first inertial measurement unit (IMU) having a gyroscope, an accelerometer, and a magnetometer; a second inertial measurement unit (IMU) (173/274) having a gyroscope, an accelerometer, and a magnetometer; at least one of (i) a tibial patient-specific anatomical mapper (PAM) that includes a surface precisely and correctly mating with a tibial surface in only a single location and orientation, where the tibial PAM is configured to be mounted to the tibial surface; and (ii) a femoral patient-specific anatomical mapper (PAM) that includes a surface precisely and correctly mating with a femoral surface in only a single location and orientation, where the femoral PAM is configured to be mounted to the femoral surface; a cutting guide configured to be repositionably coupled to the at least one of the tibial PAM and the femoral PAM , the cutting guide including at least one of a cutting slot and a pin orifice , the guide configured to couple to the first IMU in a predetermined known position and orientation; and a mechanical connection comprising at least two joints to operatively couple the cutting guide to the at least one of the tibial PAM and the femoral PAM ; wherein the second IMU (173/274) is configured to be operatively coupled to the at least one of the tibial PAM and the femoral PAM , wherein the at least two joints comprise a pair of revolute joints and a spherical joint . a first inertial measurement unit (IMU) having a gyroscope, an accelerometer, and a magnetometer; a second inertial measurement unit (IMU) (173/274) having a gyroscope, an accelerometer, and a magnetometer; at least one of (i) a tibial patient-specific anatomical mapper (PAM) that includes a surface precisely and correctly mating with a tibial surface in only a single location and orientation, where the tibial PAM is configured to be mounted to the tibial surface; and (ii) a femoral patient-specific anatomical mapper (PAM) that includes a surface precisely and correctly mating with a femoral surface in only a single location and orientation, where the femoral PAM is configured to be mounted to the femoral surface; (i) a tibial patient-specific anatomical mapper (PAM) that includes a surface precisely and correctly mating with a tibial surface in only a single location and orientation, where the tibial PAM is configured to be mounted to the tibial surface; and (ii) a femoral patient-specific anatomical mapper (PAM) that includes a surface precisely and correctly mating with a femoral surface in only a single location and orientation, where the femoral PAM is configured to be mounted to the femoral surface; a cutting guide configured to be repositionably coupled to the at least one of the tibial PAM and the femoral PAM , the cutting guide including at least one of a cutting slot and a pin orifice , the guide configured to couple to the first IMU in a predetermined known position and orientation; and a mechanical connection comprising at least two joints to operatively couple the cutting guide to the at least one of the tibial PAM and the femoral PAM ; wherein the second IMU (173/274) is configured to be operatively coupled to the at least one of the tibial PAM and the femoral PAM , wherein the at least two joints comprise a pair of revolute joints and a spherical joint . <EOS>