An electrode assembly for the positioning of an electrode of an implantable medical lead includes a housing and an electrode subassembly. The housing includes a proximal end for connecting to the lead and a distal end. The housing defines a housing lumen extending between the proximal end and the distal end. The housing lumen includes internal screw threads extending along at least a portion of the housing lumen. The electrode subassembly is disposed at least partially within the housing lumen. The electrode subassembly includes a needle electrode and a coupler. The needle electrode is disposed coaxially with the longitudinal axis of the housing lumen. The coupler is disposed at a proximal end of the needle electrode. The coupler includes external screw threads engaged with the internal screw threads of the housing lumen such that rotation of the coupler moves the needle electrode along the longitudinal axis of the housing lumen.