MAKO Surgical Corp. has developed a robotic surgical system using a robotic arm equipped with a saw that allows more patients to have partial knee replacement surgery, which is difficult to do by eye.

The MAKO system generates a 3-D model of a patient’s knee, which surgeons use to determine how much bone to remove from the tibia and femur, and where to place the implants that replace inflammed parts of these bones. They manipulate a robotic arm. Haptic feedback creates a wall of resistance if the surgeon moves outside the pre-planned bone-removal area, and the system turns the saw off if the surgeon persists.

The robotic arm is based on one developed in the 1990s at MIT by Rodney Brooks.