Minimally invasive surgical clamps, assemblies and methods
View Patent ↗A minimally invasive surgical assembly broadly includes an outer tube which has an outer diameter of 3.0 mm or smaller, and a coaxial surgical instrument having a shaft which extends through the outer hollow tube. The coaxial surgical instrument includes end effectors at the end of the shaft. The end effectors include spring arms and wire frame clamp elements defining fenestrations. The spring arms are biased to an open position such that when the end effectors of the surgical instrument extend out of the outer tube they open, and they are closed by relative movement of the outer tube over them. The wire frame clamp elements are biased to an open position such that when they extend out of the outer tube they open and they are closed by relative movement of the outer tube over them.
1. A surgical assembly, comprising:
a hollow tube having an outer diameter of 3 mm or less and an inner diameter; and
a surgical instrument having a shaft which extends through said hollow tube, said surgical instrument being movable relative to said hollow tube and including first and second end effectors at an end of said shaft, said first and second end effectors having corresponding first and second unitary spring arms extending to corresponding first and second clamp elements, the first clamp element including a first closed-loop wire frame that defines a corresponding first fenestration wherein the first closed-loop wire frame defines a closed loop that completely encircles the corresponding first fenestration and is disposed distally relative to the first unitary spring arm, the second clamp element including a second closed-loop wire frame that defines a corresponding second fenestration wherein the second closed-loop wire frame defines a closed loop that completely encircles the corresponding second fenestration and is disposed distally relative to the second unitary spring arm,
wherein said first and second unitary spring arms are biased to an open position, when said first and second unitary spring arms extend sufficiently out of said hollow tube, such that said first and second clamp elements span a distance at least twice the outer diameter of said hollow tube,
wherein, when said hollow tube extends sufficiently over said first and second unitary spring arms, said first and second clamp elements are forced into a closed position adjacent each other, and said first and second clamp elements are configured so that areas of the first and second fenestrations in said closed position of said first and second clamp elements are reduced relative to corresponding areas of the first and second fenestrations in said open position of said first and second unitary spring arms,
wherein said first and second unitary spring arms open and close relative to one another in a first direction, and the areas of the first and second fenestrations reduce in size by bending of the respective first and second closed-loop wire frames of said first and second clamp elements in a second direction orthogonal to said first direction independent of movement of said first and second unitary spring arms, and
wherein the first and second fenestrations of said first and second clamp elements are fully expanded when the first and second closed-loop wire frames initially extend completely out of said hollow tube, in a distal direction, while inner clamping surfaces of said first and second clamp elements remain in contact with each other as the first and second fenestrations expand in size.
2. The surgical assembly according to claim 1 , wherein, in said open position of said first and second unitary spring arms, the first and second fenestrations defined by the first and second closed-loop wire frames of said first and second clamp elements each have a maximal width that is larger than said outer diameter of said hollow tube.
3. The surgical assembly according to claim 2 , wherein said maximal width is at least 25% larger than said outer diameter of said hollow tube.
4. The surgical assembly according to claim 3 , wherein, in said open position of said first and second unitary spring arms, said first and second clamp elements span a distance therebetween which is at least four times said outer diameter of said hollow tube.
5. The surgical assembly according to claim 1 , wherein, said first and second clamp elements have a distal tip substantially 2 mm wide.
6. The surgical assembly according to claim 5 , wherein said first and second clamp elements are each substantially 0.5 mm thick.
7. The surgical assembly according to claim 1 , wherein said first and second clamp elements have opposed inner clamping surfaces having serrations.
8. The surgical assembly according to claim 1 , further comprising:
a first handle coupled to a proximal end of said hollow tube;
a second handle coupled to a proximal end of said shaft; and
a stop element which prevents removal of said surgical instrument completely from said hollow tube.
9. The surgical assembly according to claim 1 , wherein said hollow tube is a needle having a sharp angled distal end capable of puncturing skin of a patient.
10. The surgical assembly according to claim 1 , wherein said first and second clamp elements gradually transition from a partially opening position to a fully open position, where the inner clamping surfaces are no longer in contact with each other, as said first and second unitary spring arms are extended from said hollow tube.
11. The surgical assembly according to claim 1 , wherein said first and second clamp elements have an outer periphery forming a profile corresponding to an outer periphery of said shaft when said first and second clamp elements are retracted within said hollow tube.
12. A surgical assembly, comprising:
a hollow tube having an outer diameter of 3 mm or less and an inner diameter; and
a surgical instrument consisting essentially of a handle, a shaft which extends through said hollow tube, and first and second end effectors rigidly connected to said shaft, said surgical instrument being movable relative to said hollow tube, said first and second end effectors having corresponding first and second unitary spring arms extending to corresponding distal first and second clamp elements, the first clamp element including a first closed-loop wire frame that defines a corresponding first fenestration wherein the first closed-loop wire frame defines a closed loop that completely encircles the corresponding first fenestration and is disposed distally relative to the first unitary spring arm, the second clamp element including a second closed-loop wire frame that defines a corresponding second fenestration wherein the second closed-loop wire frame defines a closed loop that completely encircles the corresponding second fenestration and is disposed distally relative to the second unitary spring arm,
wherein said first and second unitary spring arms are biased to an open position, when extended out of said hollow tube, such that said first and second clamp elements span a distance at least twice the outer diameter of said hollow tube between entirely fenestrated portions of the first closed-loop wire frame and the second closed-loop wire frame,
wherein the first and second fenestrations defined by the first and second closed-loop wire frames of said first and second clamp elements automatically open such that the areas of the first and second fenestrations expand in size by bending of the respective first and second closed-loop wire frames of said first and second clamp elements in a direction orthogonal to a direction of opening and closing of said first and second unitary spring arms, and the first and second fenestrations expand independent of movement of said first and second unitary spring arms, and
wherein the first and second fenestrations of said first and second clamp elements are fully expanded when the first and second closed-loop wire frames initially extend completely out of said hollow tube, in a distal direction, while inner clamping surfaces of said first and second clamp elements remain in contact with each other as the first and second fenestrations expand in size.
13. The surgical assembly according to claim 12 , wherein, in said open position of said first and second unitary spring arms, the first and second fenestrations defined by the first and second closed-loop wire frames of said first and second clamp elements have a maximal width that is at least 25% larger than said outer diameter of said hollow tube, and said first and second clamp elements span a distance therebetween which is at least four times said outer diameter of said hollow tube.
14. The surgical assembly according to claim 13 , wherein said first and second clamp elements each have a distal tip substantially 2 mm wide, and said first and second clamp elements are substantially 0.5 mm thick.
15. The surgical assembly according to claim 12 , wherein said handle includes a stop element which prevents removal of said surgical instrument completely from said hollow tube.
16. The surgical assembly according to claim 12 , wherein said hollow tube is a needle having a sharp angled distal end capable of puncturing skin of a patient.
17. The surgical assembly according to claim 12 , wherein said first and second clamp elements gradually transition from a partially opening position to a fully open position, where the inner clamping surfaces are no longer in contact with each other, as said first and second unitary spring arms are extended from said hollow tube.
18. The surgical assembly according to claim 12 , wherein said first and second clamp elements have an outer periphery forming a profile corresponding to an outer periphery of said shaft when said first and second clamp elements are retracted within said hollow tube.