Patent ID: 8206397

Claim:
A medical instrument for preparation of a disc space between adjacent vertebrae of a patient, comprising: a distractor including a distraction head adapted to distract the adjacent vertebrae from an oblique approach with respect to a sagittal plane of the patient, said distraction head including opposite first and second side walls extending along a longitudinal axis to a leading portion, said leading portion of said distraction head further including a first leading edge extending from said first side wall and a second angled leading edge extending from said second side wall toward said first leading edge, said second leading edge forming an oblique angle with respect to said first leading edge, wherein said first leading edge and said second leading edge each have adjoining upper and lower tapered surfaces that extend away from one another in a direction away from respective ones of said first and second leading edges, wherein: said upper and lower tapered surfaces respectively adjoin upper and lower distraction surfaces, and said upper and lower distraction surfaces extend between said first and second side walls; said upper distraction surface terminates in an upper bone engaging surface, and said lower distraction surface terminates in a lower bone engaging surface; and said upper and lower bone engaging surfaces project outwardly in opposite directions from respective ones of said upper and lower distraction surfaces and are each defined by a concave arcuate surface facing toward said leading portion with said concave curvature extending away from said leading portion, said concave arcuate surfaces each defined by an off-centered radius of curvature, said upper and lower bone engaging surfaces each including a leading end adjacent said first side wall and an opposite trailing end adjacent said second side wall, said leading end extending more distally toward said first leading edge than said trailing end.