Computer-assisted surgery system

A computer-assisted surgery system for treating a region of interest of an anatomical structure with a surgical tool according to a surgical plan, comprising:

• a robotic arm comprising at least three motorized joints;
• a surgical tool attached to the robotic arm;
• a handle comprising:
• a fixing part attached to the robotic arm in a fixed position relative to the surgical tool, and
• a movable part mounted on the fixing part so as to be movable relative to the fixing part according to at least three degrees of freedom,
• at least one activation mechanism configured to control at least one working parameter of the surgical tool;
• a localization unit comprising at least one first tracker configured to be coupled to the surgical tool and at least one second tracker configured to be coupled to the anatomical structure defining a reference frame of the patient, the localization unit being configured to determine in real time a position and orientation of the surgical tool in the reference frame of the patient;
• and
• a control unit configured to send instructions to at least one motorized joint to move the robotic arm,
• the computer-assisted surgery system being operable in an operative mode allowing a user to control movements of the surgical tool by providing to the control unit inputs in the form of measured displacements of the movable part with respect to the fixing part applied by the user to the movable part of the handle while treating the region of interest with the surgical tool,
• wherein the control unit is configured to, as long as the operative mode is enabled:
• enable motion of the surgical tool with respect to the anatomical structure only if a user moves the movable part of the handle,
• receive the measured displacement of the movable part with respect to the fixing part of the handle,
• based on said measured displacement, determine an intended direction of displacement along which the user wants the surgical tool to be displaced and a requested displacement speed,
• receive from the localization unit the position and orientation of the surgical tool in the reference frame of the patient,
• based on the intended direction of displacement of the surgical tool, on the requested displacement speed, on the surgical plan and on the position and orientation of the surgical tool in the reference frame of the patient, compute an optimal trajectory and an optimal displacement speed of the surgical tool and compute at least one instruction to be sent to at least one of the motorized joints to move the robotic arm to operate the surgical tool according to the optimal trajectory and optimal displacement speed, and
• send the computed instruction to at least one of the motorized joints.