Electric motor driven tool for orthopedic impacting

Abstract

An orthopedic impacting tool comprises a motor, an energy storage chamber, a striker, and an anvil. The motor stores energy in the energy storage chamber and then releases it, causing the striker to apply a controlled force on an adapter to create a precise impact for use in a surgical setting. The tool may further comprise a combination anvil and adapter. The tool further allows forward or backward impacting for expanding the size or volume of the opening or for facilitating removal of a broach, implant, or other surgical implement from the opening. An energy adjustment control of the tool allows a surgeon to increase or decrease the impact energy. A light source and hand grips improve ease of operation of the tool.

What is claimed is: 
     
       1. An orthopedic impacting tool for striking an object, the tool comprising:
 a motor;   a linear motion converter;   an energy storage means;   a detent;   a control means;   an adapter, said adapter capable of holding a broach, chisel or other surgical implement; and   a striker, said striker capable of impacting at least two distinct impact surfaces, wherein a first impact surface moves said adapter forward and a second impact surface moves said adapter rearward,   wherein said control means directs said motor to store an energy in said energy storage means and said energy storage means thereafter releases the energy onto said striker causing said striker to move from a first position to a second position such that said striker is capable of imparting a force upon said adapter in a direction that is dependent at least in part on which surface said striker impacts.   
     
     
       2. The tool as claimed in  claim 1 , wherein said impact surface being impacted is controlled by a bias that a user puts on the tool. 
     
     
       3. The tool as claimed in  claim 1 , wherein said energy storage means includes a chamber operating at less than 9 psia or a pressure in excess of 50 psia at or near the point of peak energy storage. 
     
     
       4. The tool as claimed in  claim 1 , wherein said detent retains said striker in said first position until said detent is released or overcome thus allowing said energy storage means to release the energy onto said striker. 
     
     
       5. The tool as claimed in  claim 1 , wherein said energy storage means further comprises a valve. 
     
     
       6. The tool as claimed in  claim 1 , wherein the tool further comprises an energy control element, said energy control element used to adjust the impact energy said striker exerts on said adapter. 
     
     
       7. The tool as claimed in  claim 1 , wherein the tool further comprises a stroke limiter, said stroke limiter limiting a stroke of said adapter to less than fifty percent of a stroke of said striker. 
     
     
       8. A surgical impactor for striking an object with a repeatable, controlled striking force to impel a surgical implement in one of at least two opposing directions, the impactor comprising:
 a motion generation mechanism for producing the striking force;   an impact controller for controlling storage and release of energy output from the motion generation mechanism to an energy storage device to produce the repeatable, controlled striking force;   an anvil;   a surface of a striker operable to impact a first surface and a different second surface of the anvil responsive to the repeatable, controlled striking force delivered thereto, the impact of the surface of the striker on the first surface impelling the surgical implement in a first direction and the impact of the surface of the striker on the second surface impelling the surgical implement in a direction opposite the first direction; and   a detent mechanism to bias the striker in a start position.   
     
     
       9. The impactor of claim 8, wherein a selection of a direction of impact on the first and second surfaces of the anvil is based upon a user bias force applied to the impactor. 
     
     
       10. The impactor of claim 9, wherein the user bias force in a direction of the object causes the surface of the striker to impact the first surface of the anvil. 
     
     
       11. The impactor of claim 9, wherein the user bias force in a direction away from the object causes the surface of the striker to impact the second surface of the anvil. 
     
     
       12. The impactor of claim 8, wherein the energy storage device includes a chamber operating between 0 and 9 psia for a portion of a storage cycle. 
     
     
       13. The impactor of claim 8, wherein the energy storage device includes a chamber that is under at least a partial vacuum when the surface of the striker impacts the first surface to impel the surgical implement in the first direction. 
     
     
       14. The impactor of claim 8, wherein the energy storage device is a compressed air storage chamber. 
     
     
       15. The impactor of claim 8, further comprising:
 an impact adjustment mechanism to adjust the striking force the striker delivers to the first surface or the different second surface of the anvil in accordance with a patient profile.   
     
     
       16. The impactor of claim 8, further comprising:
 a linear motion conversion mechanism to convert the output of the motion generation mechanism to a linear motion.   
     
     
       17. The impactor of claim 16, further comprising:
 a sensor operably linked to the energy controller to regulate the linear motion conversion mechanism to a preferred cyclic operation.   
     
     
       18. The impactor of claim 17, wherein the sensor detects a position of the linear motion conversion mechanism to limit a stroke to a percentage less than full power. 
     
     
       19. The impactor of claim 8, wherein upon release of the detent mechanism, a retention force of the dent on the striker is reduced by at least fifty percent within a first thirty percent of a stroke of the striker. 
     
     
       20. The impactor of claim 8, further comprising:
 an adapter for receiving the surgical implement to interface the object.   
     
     
       21. The impactor of claim 20, wherein the striker is operably linked to the adapter by the impact of the striker on the first and second surfaces of the anvil. 
     
     
       22. The impactor of claim 20, wherein the adapter is releasably connected to the surgical implement. 
     
     
       23. The impactor of claim 8, wherein the striker moves in a substantially axial direction along a guide portion having openings therein for venting air during operation. 
     
     
       24. A surgical impactor for striking an object with a repeatable, controlled striking force to impel a surgical implement in one of at least two opposing directions, the impactor comprising:
 a motion generation mechanism for driving the impactor;   an impact controller for controlling storage and release of energy output from the motion generation mechanism to an energy storage device to produce the repeatable, controlled striking force;   an anvil;   a surface of a striker operable to impact a first surface and a different second surface of the anvil responsive to the repeatable, controlled striking force delivered thereto, the impact of the surface of the striker on the first surface impelling the surgical implement in a first direction and the impact of the surface of the striker on the second surface impelling the surgical implement in a direction opposite the first direction; and   a detent mechanism to bias the striker in a start position.