An end effector assembly, comprising: first and second jaw members (110, 120) having a curved configuration and disposed in opposed relation to each other, at least one of the jaw members moveable from a first, open position to a second, closed position for grasping tissue therebetween, at least one of the first and second jaw members including an electrically conductive sealing surface, and at least one of the jaw members including: a ledge disposed along the length of the at least one of the jaw members, the ledge including a top portion and a bottom portion (122b within the jaw member); a first knife channel defined along the length of at least a portion of the ledge, and a second knife channel defined along the length of at least a portion of the jaw member, and within the jaw member, below the bottom portion of the ledge such that the ledge covers a portion of the second knife channel; and a knife body including a knife blade at a distal end thereof and a recessed portion proximal to the knife blade, wherein the knife blade is configured to travel at least in the first knife channel and the recessed portion is configured to travel within the second knife channel, wherein the recessed portion has a height less than a height of the second knife channel and a width such that the recessed portion is captured and retained underneath the bottom portion of the ledge, characterised in that the ledge is formed by a portion of an electrode plade and in that the height of the knife body along the recessed portion is lower than the height of the knife blade. first and second jaw members (110, 120) having a curved configuration and disposed in opposed relation to each other, at least one of the jaw members moveable from a first, open position to a second, closed position for grasping tissue therebetween, at least one of the first and second jaw members including an electrically conductive sealing surface, and at least one of the jaw members including: a ledge disposed along the length of the at least one of the jaw members, the ledge including a top portion and a bottom portion (122b within the jaw member); a first knife channel defined along the length of at least a portion of the ledge, and a second knife channel defined along the length of at least a portion of the jaw member, and within the jaw member, below the bottom portion of the ledge such that the ledge covers a portion of the second knife channel; and a ledge disposed along the length of the at least one of the jaw members, the ledge including a top portion and a bottom portion (122b within the jaw member); a first knife channel defined along the length of at least a portion of the ledge, and a second knife channel defined along the length of at least a portion of the jaw member, and within the jaw member, below the bottom portion of the ledge such that the ledge covers a portion of the second knife channel; and a knife body including a knife blade at a distal end thereof and a recessed portion proximal to the knife blade, wherein the knife blade is configured to travel at least in the first knife channel and the recessed portion is configured to travel within the second knife channel, wherein the recessed portion has a height less than a height of the second knife channel and a width such that the recessed portion is captured and retained underneath the bottom portion of the ledge, characterised in that the ledge is formed by a portion of an electrode plade and in that the height of the knife body along the recessed portion is lower than the height of the knife blade.