Clamp for positioning a superelastic osteosynthesis clip
View Patent ↗A clamp has two arms with gripping jaws for supporting and positioning a superelastic osteosynthesis clip, The osteosynthesis clip comprising a web from which two flanges to be inserted into two portions of bone emerge. The clamp also has a component for preventing the jaws from being opened beyond a point at which the angle between the flanges of a clamp supported clip is greater than 90°; and a second component for preventing the jaws from being closed beyond a point at which the angle between the flanges and the web is substantially 90°.
1. A clamp comprising two arms pivotally connected to each other, the arms having opposed gripping jaws supporting and positioning a superelastic osteosynthesis clip, said osteosynthesis clip comprising a web from which two flanges adapted to be inserted into two portions of bone emerge, said clamp further comprising:
a first means for preventing the jaws when supporting the clip from over-opening the clip beyond a limited extent at which an angle between the flanges and the web is greater than 90°; and
a second means for preventing the jaws from being closed beyond a point at which the angle between the flanges and the web is substantially 90°.
2. The clamp as claimed in claim 1 , wherein the first means comprises a component separately mounted on one of the arms.
3. The clamp as claimed in claim 1 , wherein the first means comprises a protuberance on one of the arms.
4. The clamp as claimed in claim 3 , wherein the first means comes into contact with an opposite arm of said two arms in order to prevent said opening of the jaws.
5. The clamp as claimed in claim 1 , wherein the second means comprises a component separately mounted on one of the arms and comprising at least one tooth that cooperates with a sharp edge on an opposite arm of the two arms.
6. The clamp as claimed in claim 5 , wherein the component can swivel relative to the arm on which the component is mounted.
7. The clamp as claimed in claim 1 , wherein the first means is adjustable so as to allow variation in an extent of over-opening of the clip.
8. The clamp as claimed in claim 1 , wherein the second means is adjustable so as to allow parallel positioning of the flanges of the clip depending on size of the web.
9. The clamp as claimed in claim 1 , wherein, for a superelastic osteosynthesis clip which has a deformation curve as a function of stress having a line B-C that represents opening of said clip and a line C-B′-A′ that represents clip closing, over-opening of said clip by the first means corresponds substantially to portion C-C′ of the curve where C′ corresponds to intersection of tangent lines between a return plateau, closure B′-A′ and a fall from C.