Electrically weldable suture material, and apparatus and method for forming welded suture loops and other welded structures

An end effector for a suturing device, the end effector comprising:

• a first arm having a tissue-engaging surface and defining a first suture passage;
• a second arm having a tissue-engaging surface, the second arm comprising an opening therein;
• at least one of said first and second arms being moveable (i) toward the other of said first and second arms so as to clamp tissue between said tissue-engaging surface of said first arm and said tissue-engaging surface of said second arm, and (ii) away from the other of said first and second arms so as to release tissue clamped between said tissue-engaging surface of said first arm and said tissue-engaging surface of said second arm;
• and
• a needle defining a second suture passage and having a penetrating tip configured to penetrate tissue, said needle moveably coupled relative to said first arm and the second arm so as to be moveable between a first position in which said penetrating tip of said needle is adjacent to said tissue-engaging surface of said first arm, and a second position in which said needle is spaced from said tissue-engaging surface of said first arm,
• wherein said needle is configured to pass through said opening in said second arm as said needle moves between said first position and said second position, and
• wherein, in said first position of the needle, said first suture passage and said second suture passage form a continuous suture passage configured to receive suture along a loop shape path defined by said continuous suture passage;
• wherein a portion of said needle is spaced apart from said second arm and said second arm is between said needle and said first arm in said second position of said needle.