Date of this Version
A thesis presented to the faculty of the Graduate College at the University of Nebraska in partial fulfillment of requirements for the degree of Master of Science
Major: Mechanical Engineering and Applied Mechanics
Under the supervision of Professor Carl Nelson
Lincoln, Nebraska, November 2023
Colectomies are a common procedure used to treat a variety of diseases including colon and rectal cancers. In recent years, surgeons have been gradually transitioning from open surgery colectomies to a minimally invasive approach, which has been shown to have markedly superior outcomes for the patient in both the near and long term. However, in some cases where a resection operation is required in the pelvic region, due to a combination of space and instrument mobility limitations, current devices are unable to make the optimal cut, resulting in sub-optimal outcomes for the patient. Of concern in such a scenario is that the length of the jaw and articulation joint, in combination with the deflection limit of the joint itself, which together make proper orientation of the instrument in the constrained environment difficult to achieve. To address this, a surgical stapler design is developed with enhanced mobility and compactness at the working end for colorectal minimally invasive surgery. This is achieved by a novel articulation and cabling system, which reduces the bulk of the articulation joint, decreases overall size of the jaw, and allows deflection of up to +/-90 degrees without a decrease in surgical functionality. The design process and associated design decisions are discussed, and the instrument's underlying kinematics and subsystems are explained. Overall performance of a prototype is presented.
Advisor: Carl Nelson