A device for introduction into a body along a substantially straight elongated-element-restricting structure, the device assuming within the body a predefined curved configuration, the device comprising: an elongated element formed primarily from a plurality of segments sequentially interconnected so as to form an effective hinge between adjacent of the segments, the segments and the effective hinges being configured such that: (a) when the elongated element is confined to a substantially straight state, the effective hinges transfer compressive forces from each segment to the next so that the elongated element can be pushed so as to advance through the substantially straight elongated-element-restricting structure; and (b) when the elongated element is not confined to a substantially straight state, the effective hinges allow deflection of each segment relative to adjacent segments until at least one abutment surface of each of the segments comes into abutment with at least one corresponding abutment surface of each adjacent segment, thereby defining a fully flexed state of the elongated element, the fully flexed state corresponding to a predefined curved configuration of the elongated element, characterised in that the effective hinges in at least a portion of said elongated element are oriented at an oblique angle to a direction of elongation of the elongated element such that the predefined curved configuration has non-planar geometry. an elongated element formed primarily from a plurality of segments sequentially interconnected so as to form an effective hinge between adjacent of the segments, the segments and the effective hinges being configured such that: (a) when the elongated element is confined to a substantially straight state, the effective hinges transfer compressive forces from each segment to the next so that the elongated element can be pushed so as to advance through the substantially straight elongated-element-restricting structure; and (b) when the elongated element is not confined to a substantially straight state, the effective hinges allow deflection of each segment relative to adjacent segments until at least one abutment surface of each of the segments comes into abutment with at least one corresponding abutment surface of each adjacent segment, thereby defining a fully flexed state of the elongated element, the fully flexed state corresponding to a predefined curved configuration of the elongated element, (a) when the elongated element is confined to a substantially straight state, the effective hinges transfer compressive forces from each segment to the next so that the elongated element can be pushed so as to advance through the substantially straight elongated-element-restricting structure; and (b) when the elongated element is not confined to a substantially straight state, the effective hinges allow deflection of each segment relative to adjacent segments until at least one abutment surface of each of the segments comes into abutment with at least one corresponding abutment surface of each adjacent segment, thereby defining a fully flexed state of the elongated element, the fully flexed state corresponding to a predefined curved configuration of the elongated element,