Apparatus for axial compression of a patient's spine

Abstract

A spinal compression device includes a shoulder harness, a footplate assembly connected to the shoulder harness by at least one connecting member, At least one hydraulic actuator is mechanically coupled to the footplate assembly. The hydraulic actuator has proximal and distal ends and a piston mechanically coupled to the connecting member. A hydraulic energy source is in fluid communication with the hydraulic actuator through hydraulic lines. The footplate assembly is only connected to the hydraulic source by the hydraulic lines.

1 . A spinal compression device, comprising: 
 a shoulder harness;    a footplate assembly connected to said shoulder harness by at least one connecting member;    at least one hydraulic actuator mechanically coupled to said footplate assembly, said hydraulic actuator having a proximal end, a distal end, and a piston mechanically coupled to said connecting member; and    a hydraulic energy source in fluid communication with said hydraulic actuator through hydraulic lines;    wherein said footplate is only connected to said hydraulic source by said hydraulic lines.    
   
   
       2 . The device of  claim 1 , wherein said hydraulic energy source comprises a flexible reservoir and a pump.  
   
   
       3 . The device of  claim 2 , wherein said pump comprises an input in fluid communication with said flexible reservoir and an output in fluid communication with said distal end of said hydraulic actuator.  
   
   
       4 . The device of  claim 3 , further comprising a valve intermediate and in fluid communication with said output of said pump and said distal end of said hydraulic cylinder.  
   
   
       5 . The device of  claim 4 , wherein hydraulic fluid is permitted to flow between said pump and said distal end of said hydraulic chamber when said valve is in a first position and hydraulic fluid is prevented from flowing between said pump and said distal end of said hydraulic chamber when said valve is in a second position.  
   
   
       6 . The device of  claim 2 , wherein said flexible reservoir comprises an input in fluid communication with said proximal end of said hydraulic actuator and an output in fluid communication with said pump.  
   
   
       7 . The device of  claim 1 , wherein adding hydraulic fluid to said distal end of said hydraulic actuator increases axial force on said shoulder harness in a direction toward said footplate.  
   
   
       8 . The device of  claim 1 , wherein adding hydraulic fluid to said proximal end of said hydraulic actuator decreases axial force on said shoulder harness in a direction toward said footplate.  
   
   
       9 . The device of  claim 1 , wherein said connecting member comprises a non-distensible strap.  
   
   
       10 . The device of  claim 1 , further comprising a gauge coupled to said footplate assembly for measuring a pressure exerted on said footplate assembly.  
   
   
       11 . The device of  claim 10 , wherein said gauge outputs an indication of intra-disc pressure experienced by a patient based on a correlation of said pressure exerted on said footplate assembly and said intra-disc pressure.  
   
   
       12 . The device of  claim 11 , wherein said gauge is located at a remote location away from said footplate assembly.  
   
   
       13 . The device of  claim 1 , wherein said hydraulic source is located at a remote location away from said footplate assembly.  
   
   
       14 . A method of examining a spinal intra-disc region, comprising: 
 coupling a shoulder harness to a patient;    placing the feet of said patient in contact with a footplate, said footplate being coupled on one side to said shoulder harness by a coupling member and to at least one hydraulic piston of a hydraulic actuator on another side;    pumping hydraulic fluid into an end of said hydraulic actuator; and    imaging said intra-disc region;    wherein said pumping retracts said hydraulic piston and exerts an axial force on said shoulder harness towards said footplate.    
   
   
       15 . The method of  claim 14 , further comprising performing a preliminary imaging operation on said intra-disc region before pumping said hydraulic fluid.  
   
   
       16 . The method of  claim 14 , wherein imaging said intra-disc region includes performing a magnetic resonance imaging operation.  
   
   
       17 . The method of  claim 14 , wherein said axial force produces a pressure within said intra-disc region of about 150 kPa.  
   
   
       18 . The method of  claim 14 , further comprising monitoring a gauge, said gauge being configured to display an intra-disc pressure value based on a correlation between pressure on said footplate assembly and intra-disc pressure.  
   
   
       19 . The method of  claim 14 , further comprising releasing said hydraulic fluid from said end of said hydraulic actuator if said force is maintained for a maximum time threshold.  
   
   
       20 . The method of  claim 14 , further comprising releasing said hydraulic fluid from said end of said hydraulic actuator if said force reaches a maximum threshold.