Surgical Clamp For Cylindrical Stock
A U-type clamp has two arms and a base and tightens around cylindrical stock. The surface of the clamp that makes contact with the cylindrical stock is not itself entirely cylindrical in its loosened state. The preferred embodiment involves a first cylindrical profile extending around about ¾ of the contact surface which is intended to match the curvature of the post. The final ¼ or so of contact surface has a larger radius of curvature than the first cylindrical profile. The second cylindrical profile may also be offset relative to the first cylindrical profile.
1 . A U-type surgical clamp comprising:
a first leg of a U-shape;
a second leg of the U-shape; and
a base of the U-shape connecting the first leg to the second leg, such that the U-type surgical clamp can be tightened onto cylindrical stock by drawing the first leg and the second leg closer together, wherein the base defines a contact surface for contacting the cylindrical stock, wherein the contact surface, in its loosened state, comprises:
a first portion having a first curvature; and
a second portion having a second curvature distinctly different from the first curvature.
2 . The U-type surgical clamp of claim 1 , wherein the first portion is cylindrical, and wherein the second portion is cylindrical.
3 . The U-type surgical clamp of claim 2 , wherein the first portion has a first radius of curvature, and wherein the second portion has a second radius of curvature which is larger than the first radius of curvature.
4 . The U-type surgical clamp of claim 3 , wherein the first portion and the second portion are connected with a flat.
5 . The U-type surgical clamp of claim 4 , wherein the first radius of curvature defines a first central axis, wherein the second radius of curvature defines a second central axis, with the second central axis being offset relative to the first radius of curvature.
6 . The U-type surgical clamp of claim 4 , wherein the flat has a length of 0.001 to 0.05 inches.
7 . The U-type surgical clamp of claim 3 , wherein the second radius of curvature is within the range of 0.001 to 0.05 inches larger than the first radius of curvature.
8 . The U-type surgical clamp of claim 1 , wherein the first portion extends over at least 180° of contact area.
9 . The U-type surgical clamp of claim 8 , wherein the second portion extends over no more than 90° of contact area.
10 . The U-type surgical clamp of claim 1 , wherein the first portion has a first radius of curvature, and wherein the second portion has a second radius of curvature which is larger than the first radius of curvature.
11 . The U-type surgical clamp of claim 10 , wherein the first portion and the second portion are connected with a flat.
12 . The U-type surgical clamp of claim 10 , wherein the first portion extends over at least 180° of contact area, and wherein the second portion extends over no more than 90° of contact area.
13 . The U-type surgical clamp of claim 1 , wherein the first portion differs from the second portion in at least one of radius of curvature and axis location.
14 . The U-type surgical clamp of claim 1 , further comprising a bolt for drawing the first leg and the second leg closer together, a cam coupled to the bolt for moving the bolt, and a cam handle attached to the cam for rotating the cam.
15 . A U-type surgical clamp comprising:
a first leg of a U-shape;
a second leg of the U-shape; and
a base of the U-shape connecting the first leg to the second leg, such that the U-type surgical clamp can be tightened onto cylindrical stock by drawing the first leg and the second leg closer together, wherein the base defines a contact surface for contacting the cylindrical stock, wherein the contact surface comprises:
a first portion having a first radius of curvature; and
a second portion having a second radius of curvature which is larger than the first radius of curvature.
16 . The U-type surgical clamp of claim 15 , wherein the first portion and the second portion are connected with a flat.
17 . The U-type surgical clamp of claim 15 , wherein the first portion extends over at least 180° of contact area, and wherein the second portion extends over no more than 90° of contact area.
18 . The U-type surgical clamp of claim 15 , further comprising a bolt for drawing the first leg and the second leg closer together, a cam coupled to the bolt for moving the bolt, and a cam handle attached to the cam for rotating the cam.
19 . A surgical clamping system comprising:
a generally cylindrical bar having a bar radius; and
a U-type clamp for clamping onto the generally cylindrical bar, comprising:
a first leg of a U-shape;
a second leg of the U-shape; and
a base of the U-shape connecting the first leg to the second leg, the base being generally sized to mate with the generally cylindrical bar, the base defining a contact surface which comprises:
a first portion having a radius of curvature which matches the bar radius; and
a second portion having a radius of curvature which is larger than the bar radius;
a bolt for drawing the first leg and the second leg closer together;
a cam coupled to the bolt for moving the bolt; and
a cam handle attached to the cam for rotating the cam, the cam handle having a throw to tighten the clamp so as to force the second portion into contact with the generally cylindrical bar.