An apparatus for detecting the presence of a connecting rod during percutaneous spinal surgery comprises a tubular member and an elongate strip extending therethrough. The strip has a flag at the proximal end and an elastically flexible rod detection tip projecting outwardly from the distal end for contacting a connecting rod. The strip is supported in the tubular member for pivoting movement relative to the longitudinal axis of the member. A biasing member biases the strip to a first position in which the flag is adjacent a first side of the tubular member and the detection tip at the distal end is adjacent an opposite second side. Upon application of a force to elastically flex the detection tip, in which the force is sufficient to overcome the bias, the flag is shifted to a second position adjacent the second side of the tubular member.