Robotic surgical systems for preparing holes in bone tissue and methods of their use

Abstract

Described herein are systems and methods for use in preparing holes in bones. In certain embodiments, the trajectory followed in preparing a hole in a bone is optimized by adjusting characteristics of rotation of a drill bit (e.g., an anti-skiving drill bit). In certain embodiments, a change in material is determined once a hard outer layer of a bone has been drilled. Subsequently, characteristics of rotation of a drill bit are altered to allow natural features of a patient's anatomy to guide the drill bit. In this way, certain hard walls of certain bones can act to redirect a drill bit. The change in material may be determined, and/or characteristics of rotation altered, by a surgeon or a robotic surgical system (e.g., automatically). In certain embodiments, a robotic surgical system notifies a surgeon of a change in material to prompt the surgeon to alter the characteristics of rotation.

1 . A method of drilling a hole in bone of a patient with a robotic arm of a robotic surgical system, the method comprising:
 determining a change in material at a terminal point of a drill bit; and   altering one or more characteristics of rotation of the drill bit based, at least in part, on the change in material.   
     
     
         2 . The method of  claim 1 , wherein the one or more characteristics of rotation are selected from the group consisting of rotational speed, rotational velocity, rotational direction and rotational mode. 
     
     
         3 . The method of  claim 1 , wherein the one or more characteristics of rotation is rotational speed. 
     
     
         4 . The method of  claim 1 , wherein, the method comprises measuring prior to the determining step, haptic feedback; and the determining step comprises determining the change in material based, at least in part, on the haptic feedback. 
     
     
         5 . The method of  claim 4 , wherein the haptic feedback is measured by at least one force sensor and at least one of the at least one force sensors is attached to one of the end effector, the drill, and the robotic arm. 
     
     
         6 . The method of  claim 1 , comprising: moving the drill bit along a pre determined trajectory, wherein motion of the drill bit is constrained to along the pre-determined trajectory. 
     
     
         7 . The method of  claim 1 , wherein the determining step comprises:
 determining the change in material based, at least in part, on medical image data.   
     
     
         8 . The method of  claim 1 , wherein the determining step comprises:
 determining the change in material based, at least in part, on a position of the terminal point of the drill bit.   
     
     
         9 . The method of  claim 1 , comprising: notifying a surgeon, upon determination of the change in material, with a notification, wherein the notification comprises at least one member selected from the group consisting of: haptic feedback provided to the surgeon, a sound, a graphic, and a light signal. 
     
     
         10 . The method of  claim 9 , wherein the notification prompts the surgeon to alter the one or more characteristics of rotation. 
     
     
         11 . The method of  claim 10 , wherein the one or more characteristics of rotation are selected from the group consisting of rotational speed, rotational velocity, rotational direction, and rotational mode. 
     
     
         12 . (canceled) 
     
     
         13 . A method of notifying a surgeon of a change while drilling a bone of a patient with a robotic arm of a robotic surgical system, the method comprising:
 determining a change in material at a terminal point of a drill bit; and   notifying the surgeon, upon determination of the change in material, with a notification, wherein the notification comprises at least one member selected from the group consisting of: haptic feedback provided to the surgeon, a sound, a graphic, and a light signal.   
     
     
         14 . The method of  claim 13 , wherein the notification prompts the surgeon to alter one or more characteristics of rotation. 
     
     
         15 . The method of  claim 14 , wherein the one or more characteristics of rotation are selected from the group consisting of rotational speed, rotational velocity, rotational direction, and rotational mode. 
     
     
         16 . The method of  claim 13  comprising: altering one or more characteristics of rotation of the drill bit based, at least in part, on the change in material. 
     
     
         17 . The method of  claim 16 , wherein the one or more characteristics of rotation are selected from the group consisting of rotational speed, rotational velocity, rotational direction, and rotational mode. 
     
     
         18 . The method of  claim 16 , wherein the one or more characteristics of rotation are rotational speed. 
     
     
         19 . The method of  claim 13 , wherein the method comprises measuring, prior to the determining step, haptic feedback; and the determining step comprises determining the change in material based, at least in part, on the haptic feedback. 
     
     
         20 . The method of  claim 19 , wherein the haptic feedback is measured by at least one force sensor and at least one of the at least one force sensors is attached to one of the end effector, the drill, and the robotic arm.