An electrode assembly includes electrodes and a cuff, shaped so as to define a tubular housing that defines a longitudinal axis therealong, two edges, and a slit between the two edges. When the housing is closed, respective contact surfaces of the two edges touch each other, and the housing defines an inner surface that faces and surrounds the axis, to which inner surface the electrodes are fixed. The cuff further defines three or more annular insulating elements that extend toward the axis from the inner surface of the housing at respective longitudinal positions along the housing, such that the inner surface of the housing and pairs of the insulating elements define, at respective longitudinal positions along the housing, respective chambers open toward the axis. The housing is shaped such that the contact surfaces of the two edges extend toward the axis and protrude into the chambers.
