A surgical instrument 10 for surgically joining tissue is disclosed. The instrument comprises a handle assembly 20, an elongated portion 30, an end effector 40, and an articulation mechanism 100. The elongated portion extends distally from the handle assembly. The end effector is disposed adjacent a distal portion of the elongated portion. The articulation mechanism is disposed in mechanical cooperation with the end effector for articulating the end effector. The articulation mechanism comprises a lever 120, a knob 140, a plate 260 and a lower clutch 240. The plate is disposed at least partially within a portion of the knob. The lower clutch is disposed in mechanical engagement with the plate. The plate is disposed at least partially between the lower clutch and the knob. The lower clutch is keyed to the plate to limit rotation therebetween. The lower clutch is keyed to the knob to limit rotation therebetween.
