Deformable breaking member having multiple contact portions

A medical device configured to be inserted into a body lumen to break an object in the body lumen, the medical device comprising:

• an elongated shaft;
• a deformable breaking member having a plurality of wires, and wherein proximal-side end portions of each of the plurality of wires are arranged in a circumferential direction to form a sliding portion configured to be slidable with respect to and movable along the elongated shaft and distal-side end portions of each of the plurality of wires are arranged in a circumferential direction to form a fixing portion that is fixed to the elongated shaft;
• each of the plurality of wires including a first convex portion and a middle portion proximal to the first convex portion;
• wherein when the breaking member is in a contracted state, the middle portion is a straight shape and an outermost vertex of the breaking member in a radial direction is located in the first convex portion, and when the breaking member is in an expanded state, the middle portion is a curved shape and the outermost vertex of the breaking member in the radial direction is located in the middle portion;
• and
• wherein a curvature of the first convex portion is substantially identical in both the contracted state and a natural state in which no external forces acts on each of the plurality of wires and wherein the middle section is located substantially in a center portion of the breaking member in an axial direction.

A medical device configured to be inserted into a body lumen to break an object in the body lumen, the medical device comprising:

• an elongated shaft;
• a deformable breaking member having a plurality of wires, and wherein proximal-side end portions of each of the plurality of wires are arranged in a circumferential direction to form a sliding portion configured to be slidable with respect to and movable along the elongated shaft and distal-side end portions of each of the plurality of wires are arranged in a circumferential direction to form a fixing portion that is fixed to the elongated shaft;
• each of the plurality of wires including a first convex portion and a middle portion proximal to the first convex portion;
• wherein when the breaking member is in a contracted state, an outermost vertex of the breaking member in a radial direction is located in the first convex portion;
• and
• wherein when the breaking member is in an expanded state, the middle portion is a curved shape and the outermost vertex of the breaking member in the radial direction is located in the middle portion.