| 摘要 |
<p>An instrument (10) for cutting elongated pins used in orthopedic surgery includes a housing (12) having a reduced diameter portion (14) in which is disposed a piston (30) reciprocable in a fluid chamber. An enlarged diameter portion (15) of the housing forms a further part of the fluid chamber in which is disposed a second piston (48) connected to a member forming a first cutting edge (68) which is movable toward an anvil (72) having a second cutting edge (70) cooperable with the first cutting edge (62) to shear a pin to a predetermined length. The smaller piston (30) is engaged by a screw actuator (28) disposed on the housing (12) and which may be rotated to provide a substantial force multiplication whereby a sufficient cutting force is exerted on a pin. The instrument is provided with a transverse handle portion (92) to facilitate handling and to hold the instrument against reaction forces of the screw actuator. The cutting edges are formed on cooperable anvil (72) and actuating member portions (54). A reduced diameter nose portion (16) of the instrument includes a transverse bore (74) for supporting a pin to be cut.</p> |
