The agreement may be to retract the incision and expose the surgical field. In life, the role of hooking is to make an agreement between the two parties, and it is a way to identify an agreement between children.

In surgery, a retractor means that after the skin and muscles are incised during surgery, the assistant fully exposes the surgical field by pulling the subcutaneous tissue, muscles, tendons, fascia or ligaments around the incision. Improve the quality of surgery.