Medical diagnostic instruments/systems are provided that include (i) a proximal handle configured and dimensioned to permit an operator to manually grasp the instrument; (ii) an ultrasound probe including a longitudinal shaft extending distally from the handle and terminating in a distal end, and an ultrasound transducer mounted with respect to the longitudinal shaft, the ultrasound transducer including an array of ultrasonic energy generation elements (iii) a tactile feeler probe mounted with respect to the ultrasound probe; and (iv) at least one hollow receiver member mounted with respect to the longitudinal shaft of the ultrasound probe, the at least one hollow receiver member configured to receive a K-wire to permit the instrument to be slidably mounted thereto for purposes of guiding the ultrasound and tactile feeler probes axially relative to a desired anatomical location. Advantageous methods for use of the disclosed instruments/systems are also provided.