Patent ID: 8663227

Claim:
A tubular cutting head for removing a nucleus pulposus of a subject, the cutting head having an outer perimeter that circumscribes a lumen through the cutting head, the lumen having a central axis and in an operable communication with an at least substantially rigid tube; a cutting surface on the distal perimeter of the tubular cutting head, the cutting surface having a first plane and a second plane, the first plane having a plurality of cutting surfaces and positioned at an angle, θ FP , to the central axis of the lumen of the tubular cutting head; and, the second plane having a plurality of cutting surfaces and positioned at an angle, θ SP , to the central axis of the lumen of the tubular cutting head; wherein, each of θ FP and θ SP are independently selected to deviate up to 75° from a planar position that is orthogonal to the central axis of the cutting head; the cutting surface including a forward cutting blade having a forward-directed cutting surface on a distal edge of the outer perimeter, the forward cutting blade configured for (i) cutting the nucleus pulposus tissue in a forward stroke of the cutting head and (ii) excising and directing entry of the excised nucleus pulposus tissue into the lumen on the forward stroke; a backward cutting blade having a backward-directed cutting surface and configured with a barb to hook nucleus pulposus tissue for removal of the nucleus pulposus tissue in a backward stroke of the cutting head; a transverse cutting blade having a plurality of laterally-directed cutting surfaces and configured for cutting and excising the nucleus pulposus in a transverse stroke of the cutting head, each of the plurality of laterally-directed cutting surfaces adapted as a directional shift from the forward-directed cutting surface of the forward cutting blade to a laterally-directed cutting surface; and, a blade guard positioned distal to the forward cutting blade and configured to guard an annulus fibrosis tissue from the forward cutting blade upon the forward stroke, the blade guard having a transverse, cross-sectional width that is at least substantially smaller than the width of a transverse cross-section of the lumen to facilitate the entry of the excised nucleus pulposus tissue into the lumen on the forward stroke, such that the entry of the excised nucleus pulposus tissue into the lumen on the forward stroke is reduced by less than 50% due to the presence the blade guard; wherein, the cutting head and the cutting surface are formed from a single tube and adapted for removing the nucleus pulposus of a subject, the cutting head formed at the distal end of the single tube.