A surgical instrument comprises an elongate shaft having a proximal end and a distal end. The shaft tapers distally. An actuator is connected to the proximal end of the elongate shaft. An end effector is adapted for in vivo attachment and detachment from the distal end of the elongate shaft connected to the distal end of the elongate shaft. The actuator may comprise a manual handle. The elongate shaft may comprise an outer tube and an inner rod positioned in the outer tube, with the outer tube comprising a wall thickness increasing proximally. The surgical instrument may further comprise an intermediate tube positioned between the outer tube and inner rod. The elongate shaft may be adapted for direct percutaneous insertion.
