Background: The optimal jaws of laparoscopic graspers can be used to manipulate the tissue properly with minimal damage. The criteria jaws should satisfy are investigated.
Methods: The cecum of pigs was clamped between 13 pairs of jaws differing in size and profile. Various pinch and pull forces were applied. At 5 N pull force, the minimally required pinch force to prevent slip and the pinch force that is maximally allowable without causing damage were obtained.
Results: With increasing size of the jaws, the contact area with the tissue increases. With increasing contact area, the pinch force leading to tissue damage was increased from 15 to 37 N. A profile of the jaws decreased the pinch force needed to prevent slip of tissue from 22 to 3 N.
Conclusion: An optimal jaw possesses a large contact area to prevent tissue damage and a slight profile to prevent tissue slip.