Ultrasound surgical saw

Abstract

This invention discloses methods and devices using ultrasound energy for resecting bone tissue during surgical procedures. The disclosure describes the use of ultrasound surgical saw consisting of an ultrasound generator, ultrasound transducer and ultrasound horn including a cutting blade to resect bone tissue without excessive temperature rise during typical surgical procedures. The cutting blade provides a self-clearing design that includes at least two teeth disposed to prevent accumulation of bone chips within the proximity of the teeth. The design of the cutting blade allows the mechanical motion of the blade and the emission of the ultrasound energy to remove accumulated bone chips and prevent excessive temperature rise.

1 . An apparatus for use in surgery comprising:
 an ultrasound generator driving an ultrasound transducer;   an ultrasound horn attached to an ultrasound transducer, the ultrasound horn having a cutting blade disposed along a longitudinal axis;   the cutting blade having a support structure holding a plurality of teeth;   the teeth having a cutting edge extending partially across the width of the cutting blade;   the teeth disposed along a radial edge of the longitudinal axis; and   a gullet formed between adjacent teeth interconnecting all teeth along the longitudinal axis.   
     
     
         2 . The apparatus according to  claim 1  wherein the cutting blade has a width less than 1-millimeter. 
     
     
         3 . The apparatus according to  claim 1  wherein the ultrasound horn also has a conduit for transferring a fluid. 
     
     
         4 . The apparatus according to  claim 1  wherein the ultrasound horn is partially disposed within a shield. 
     
     
         5 . The apparatus according to  claim 1  wherein the ultrasound transducer receives a modulated signal. 
     
     
         6 . The apparatus according to  claim 1  characterized by the ultrasound transducer being capable of inducing the ultrasound horn to vibrate approximately in resonance at a frequency between approximately 15 kHz and approximately 3 mHz. 
     
     
         7 . The apparatus according to  claim 1  characterized by the ultrasound transducer being capable of inducing the ultrasound horn to vibrate approximately in resonance at a frequency of approximately 30 kHz. 
     
     
         8 . The apparatus according to  claim 1  producing an electrical signal of a voltage sufficient to induce the ultrasound horn to vibrate approximately in resonance with the amplitude of the vibrations being between approximately 1 micron and approximately 100 microns. 
     
     
         9 . The apparatus according to  claim 1  wherein the characterized by the generator being capable of producing an electrical signal of a voltage sufficient to induce the ultrasound horn to vibrate approximately in resonance with the amplitude of the vibrations being approximately 80 microns. 
     
     
         10 . The apparatus of  claim 1  wherein the housing has a grip portion having a substantially axial configuration along a longitudinal axis. 
     
     
         11 . The apparatus of  claim 1  wherein the housing has a grip portion in a pistol grip configuration radial to a longitudinal axis. 
     
     
         12 . An apparatus for use in surgery comprising:
 a drive mechanism communicating with a cutting blade;   the cutting blade having a high frequency vibration along the longitudinal axis;   the cutting blade also having a support structure holding a plurality of teeth;   the teeth having a cutting edge extending partially across the width of the cutting blade;   the teeth disposed along a radial edge of the longitudinal axis; and   a gullet formed between adjacent teeth interconnecting all teeth along the longitudinal axis.   
     
     
         13 . A method of surgery on bone tissue comprising the steps of;
 generating ultrasound waves with an ultrasound transducer;   transmitting the ultrasound waves to an cutting blade connected to the ultrasound transducer;   vibrating the cutting blade sufficiently to form a kerf;   ejecting bone tissue from the kerf using the vibrating cutting blade transmitting the ultrasound waves from the cutting blade; and   using the ultrasound waves in combination with the vibrating cutting blade to dislodge bone tissue from the cutting blade for a self-cleaning blade.   
     
     
         14 . The method of  claim 13  having an additional step of stabilizing the cutting blade by forming a center ridge within the kerf. 
     
     
         15 . The method of  claim 13  having the additional step of maintaining a temperature below 75 degrees centigrade without supplemental cooling. 
     
     
         16 . The method of  claim 13  having the additional step of maintaining a temperature of approximately 55 degrees centigrade without supplemental cooling. 
     
     
         17 . (canceled)