Lordotic spinal implant
AssigneeZimmer Spine, Inc.
InventorsDouglas W. Kohrs, Paul M. Sand
Life of this patent
Estimating the term…
Abstract
A lordotic implant has a frusto-conical shape with external threads. Prior to placement of the implant, vertebrae are distracted in a manner to provide a desired lordosis between the vertebrae. The pre-distracted vertebrae are then tapped to provide a tapped bore having a geometry matching the conical geometry of the implant. The threaded implant is then placed within the pre-tapped conical bore.
Claims16
A kit for placing an implant into a disk space between opposing vertebrae having opposing end plates to be separated by a predetermined degree of lordosis, said kit comprising:
- (A) an implant having:
- a generally frusto-conical hollow body having:
- a leading end
- trailing end comprising:
- a trailing end rise
- a terminal end
- a longitudinal axis
- a first taper increasing from said leading end to said trailing end rise;
- and
- a second taper increasing from said terminal end to said terminal end rise
- said first taper of said frusto-conical body having a conical angle approximating said degree of lordosis;
- an implant thread pattern surrounding said body;
- openings formed through a conical wall of said body into an interior
- of said body with said openings formed at least on diametrically opposite sides of said body;
- (B) a tap having:
- a shaft defining a longitudinal axis;
- a tapping head at a distal end of said shaft, said tapping head having a tapping thread surrounding said axis with a thread pattern substantially matching said implant thread pattern;
- said tapping thread includes a plurality of peaks and valleys defining a conical path around said axis with a leading end tap diameter adjacent said distal end and with a trailing end tap diameter spaced from said distal end, said trailing end tap diameter being greater than said leading end tap diameter;
- said leading end tap diameter being substantially equal to said leading end implant diameter.
An implant for placement into a disk space between opposing vertebrae having opposing end plates to be separated by a predetermined degree of lordosis, said implant comprising:
- (A) a generally frusto-conical hollow body having:
- (1) a leading end with a leading end diameter;
- (2) a trailing end comprising:
- a trailing end rise having a trailing end rise diameter;
- a terminal end having a terminal end diameter;
- (3) a first taper increasing from said leading end diameter to said trailing end rise diameter;
- and
- (4) a second taper increasing from said terminal end diameter to said trailing end rise diameter.
A distraction spacer for placing an implant into a disk space between opposing vertebrae having opposing end plates separated by a predetermined degree of lordosis, said distraction spacer comprising:
- a main body;
- first and second diametrically opposed surfaces having a leading end and a trailing with a longitudinal axis passing therethrough said first and second opposed surfaces extending predominantly in the direction of the longitudinal axis and said first and second diametrically opposed surfaces converging towards said longitudinal axis from said trailing end to said leading end;
- wherein said first and second diametrically opposed surfaces are flat surfaces.
A distraction spacer for placing an implant into a disk space between opposing vertebrae having opposing end plates separated by a predetermined degree of lordosis, said distraction spacer comprising:
- a main body;
- first and second diametrically opposed surfaces having a leading end and a trailing with a longitudinal axis passing therethrough;
- said first and second opposed surfaces extending predominantly in the direction of the longitudinal axis said first and second diametrically opposed surfaces converging towards said longitudinal axis from said trailing end to said leading end;
- wherein said main body is a frusto-conical shape and said first and second diametrically opposed surfaces are portions of said frusto-conical shape.
Dependencies are inferred from the claim text.