A forceps includes first and second shaft members each having a jaw member disposed at a distal end thereof. The shaft members are moveable relative to one another between spaced-apart and approximated positions to move the jaw members between open and closed positions. A knife assembly is engaged within the second shaft member. The knife assembly includes an arm extending through a trough defined within the second shaft member and has a knife disposed at a distal end thereof. The arm is moveable between a first position, corresponding to a retracted position of the knife, wherein the arm defines an arched portion extending from the second shaft member, and a second position, wherein the arched portion defines a more linear configuration to elongated the arm distally to advance the knife between the jaw members to cut tissue grasped therebetween.