ACETABULAR REAMER

摘要

An acetabular reamer (10, 90) includes a base (12, 92), a first set (26, 120) of semi-circular blades attached to the base (12, 92), and a second set (18, 118) of semi-circular blades also contacting said base (12, 96), and crossing and intersecting with said first set of blades at right angles thereto. The base (12, 92) preferably comprises a circular plate having a hexagonal drive hole (16, 96) in the center thereof and a plurality of slots (14) in the periphery thereof for anchoring the blades. Each semi-circular blade (20-24, 28-37, 100, 104, 110-116) includes a first end having a projection thereon (46, 66, 72), a second end (48, 68) opposite from said first end (44, 64) and also having a projection (50, 70) thereon, a first edge (40, 60) having serrated cutting teeth (42, 62) thereon, a second edge (52, 72) opposite from said first edge (40, 60), and a first (22, 56) and second (24, 58) side surface. The cutting edge (60) of the first set of blades (26, 120) includes a plurality of outwardly facing slots (74a-74c) which mate with and engage a second set of inwardly facing slots (54a-54c) in the second edge of said second blades (18, 118). When the first (20, 120) and second set (18, 118) of blades are assembled in this fashion the cutting edges of both sets of blades lie in the same spherical plane. The projections can comprise snap-in projections (52, 84, 86) that automatically lock in position or projections (46, 50, 66, 70) that can be twisted and locked into position. Alternatively, the base (92) can comprise a pair of upper (94) and lower (96) plates with apertures (14) in the upper plate such that when the blade projections (102) mate with the apertures (14), riveting of the lower plate (96) with respect to the upper plate (94) locks the projections (102) and their related blades (100, 110, 112) into position on the base (92). When the reamer (10, 90) is assembled it has a hemispherical shape suitable for reaming the acetabulum of the hip so that the acetabular portion of a hip implant properly fits into the acetabulum.