Electrosurgical forceps

An electrosurgical forceps includes a pair of first and second shaft members pivotably coupled to one another, an end effector assembly coupled to the pair of first and second shaft members, a knife selectively translatable through the first shaft member and the end effector assembly, and a knife deployment mechanism. The second shaft member has a flange extending therefrom toward the first shaft member. The knife deployment mechanism includes a distal extension movably coupled to the first shaft member and configured to engage the flange of the second shaft member when the knife is an extended position and the end effector assembly is in a closed configuration. The engagement between the distal extension and the flange resists movement of the end effector assembly from the closed configuration.