A bone connector system comprises first and second connector members. At least one and preferably both of the connector members carries an external bone screw thread to permit securance within a bone. One of the connector members defines a sleeve having an outer end with longitudinal slots extending through the outer end, and a plurality of loops of an external screw thread positioned adjacent to the outer end. The other of the connector members defines a bore having a multiple loop, internal screw thread proportioned to engage the external thread when the connectors are brought together. Either or both of said connector members may define guidewire lumens.