Instruments for expandable corpectomy spinal fusion cage

Abstract

An instrument set for an intervertebral expandable spacer having a pair of co-axial annuluses locked together by an engagement member, the set including an inserter/expander having both a rapid expansion mechanism and a fine tuning expansion mechanism.

We claim: 
     
       1. An inserter/expander instrument comprising:
 a) a first longitudinal member having a distal end portion adapted for engaging a first vertebral surface, an intermediate portion, and a proximal portion, 
 b) a second longitudinal member having a distal end portion adapted for engaging a second vertebral surface, and an intermediate portion, and a proximal portion, 
 c) first and second cross bars distally pivotally attached to the longitudinal members at distal pivots; pivotally attached together at a third pivot; and slidably attached at their respective proximal ends to the opposing longitudinal member by a pin and groove arrangement, 
 d) a first expansion actuation mechanism attached to the proximal portion of the first longitudinal member, the expansion actuation mechanism adapted to incrementally distally advance the proximal portion of the first cross bar to expand the distal portions of the longitudinal members, and 
 e) a second expansion actuation mechanism attached to the proximal portion of the first longitudinal member, the second expansion actuation mechanism adapted to incrementally distally advance the proximal portion of the first cross bar to expand the distal portions of the longitudinal members,
 wherein the second expansion mechanism comprises a knob having a threaded shaft extending therefrom, the thread of the shaft mating with a thread upon on an internal diameter of a tube located with within the first longitudinal member, and 
 wherein the shaft of the knob is connected to the pin of the pin and groove arrangement, so that distal movement of the shaft of the knob results in an opening of the cross bars. 
 
 
     
     
       2. The instrument of  claim 1  wherein the first expansion mechanism comprises a pistol grip comprising a handle and lever pivotally attached to the handle. 
     
     
       3. The instrument of  claim 2  wherein the lever is pivotally attached to a shaft located within the proximal portion of the first longitudinal member. 
     
     
       4. The instrument of  claim 1  wherein the proximal portion of the first longitudinal member is cannulated. 
     
     
       5. The instrument of claim 1, wherein the first longitudinal member distal end portion is adapted for engaging a first vertebral surface and the second longitudinal member distal end portion is adapted for engaging a second vertebral surface. 
     
     
       6. The instrument of claim 1, wherein the first longitudinal member distal end portion and the second longitudinal member distal end portion are each modular. 
     
     
       7. The instrument of claim 6, wherein the first longitudinal member modular distal end portion is adapted for engaging a first vertebral surface and the second longitudinal member modular distal end portion is adapted for engaging a second vertebral surface. 
     
     
       8. The instrument of claim 6, wherein the first longitudinal member modular distal end portion and the second longitudinal member modular distal end portion are each adapted for holding an expandable implant. 
     
     
       9. The instrument of claim 1, wherein the first longitudinal member distal end portion and the second longitudinal member distal end portion are each adapted for holding an expandable implant.