A medical device is provided with a flexible shaft having a first beam element with a first elongated cross section and a second beam element having a second elongated cross section. An end effector is located at a distal end of the flexible shaft and actuated by relative movement between the first beam element and the second beam element. In another example, a handle is located at a proximate end of the flexible shaft. A first control is mounted on the handle and is directly coupled to the first beam element for placing the first beam element in tension relative to the second beam element to thereby cause bending of at least a portion of the flexible shaft toward the first beam element.