An implantable electrode paddle is adapted to receive an electrical signal from a medical device and generate an electrical field to stimulate selected body tissue. The paddle includes a housing including walls that define an interior space and a plurality of windows formed through at least a first one of the walls for transmitting the electrical field to the body tissue, an electrode array including a plurality of electrode groups, each electrode group including at least two electrodes individually secured in a respective window and spaced between about 0.1 mm and about 10 mm apart, and a plurality of wires, each of the wires being coupled to a respective electrode and routed within the interior space to receive the electrical signal. A lead assembly and an implantable medical device can include the paddle.