Interrupted sutures require the needle to be inserted at right angles to the incision and then to pass through both aspects of the suture line and exit again at right angles. It is important for the needle to be rotated through the tissues rather than to be dragged through, to avoid unnecessarily enlarging the needle hole.
As a guide, the distance from the entry point of the needle to the edge of the wound should be approximately the same as the depth of the tissue being sutured, and each successive suture should be placed at twice this distance apart (Figure). Each suture should reach into the depths of the wound and be placed at right angles to the axis of the wound. In linear wounds, it is sometimes easier to insert the middle suture first and then to complete the closure by successively inserting sutures, halving the remaining deficits in the
wound length.