A surgical instrument includes an elongated shaft having a distal portion and a proximal portion coupled to a housing. An inner shaft member extends at least partially through the elongated shaft and is selectively movable in a longitudinal direction. An end effector is supported by the distal portion of the elongated shaft. The end effector includes upper and lower jaw members pivotally coupled to the distal portion of the elongated shaft about a pivot axis and including a pair of laterally spaced flanges. The pairs of flanges of the jaw members are arranged in an offset configuration such that one flange of the upper jaw member is positioned on a laterally exterior side of a corresponding flange of the lower jaw member, and the other flange of the upper jaw member is positioned on a laterally interior side of the other flange of the lower jaw member.