A lead anchor includes a lead passageway defined along a central body and configured to receive a lead. The central body includes a twistable region that reversibly twists and stretches. First and second hubs are coupled to opposing ends of the central body. The first hub is rotatable relative to the second hub about the central body. Rotation of the first hub relative to the second hub causes twisting of the twistable region. When a lead is inserted into the lead passageway and the twistable region is twisted into a twisted configuration the central body compresses against the lead to retain the lead within the lead passageway. A locking mechanism transitions the hubs between an unlocked position, where the first hub is rotatable relative to the second hub, and a locked position, where the hubs resist rotation relative to one another.

A stimulation lead anchoring system includes a lead anchor and a removable inner core. The lead anchor includes an anchor body that includes a lead lumen that extends longitudinally along the anchor body and is configured and arranged to receive a portion of an electrical stimulation lead. The removable inner core includes a core body that includes an inner lumen that extends longitudinally along the core body. The lead anchor and removable inner core are configured and arranged to expand the anchor body when a portion of the core body is inserted into the lead lumen to facilitate receiving the portion of the electrical stimulation lead into the lead lumen and inner lumen and slidably positioning the lead anchor along the lead. The anchor body is configured and arranged to engage the portion of the electrical stimulation lead upon withdrawal of the core body from the lead lumen.

A fixation mechanism of an implantable lead includes a plurality of depressions of an outermost surface of the lead and a relatively flexible sleeve mounted around the outermost surface. The depressions are spaced apart from one another along a length, and each extends circumferentially, wherein a longitudinal center-to-center spacing between each adjacent depression is uniform along the length, and each depression is of substantially the same size. The sleeve has an internal surface in sliding engagement with the outermost surface of the lead, and an external surface, in which suture grooves are formed. A longitudinal center-to-center spacing between adjacent suture grooves may be substantially the same as, or a multiple of, the longitudinal center-to-center spacing between adjacent depressions of the outermost surface of the lead. The sleeve may also include a ridge protruding from the internal surface, aligned with, or offset (by center-to-center spacing of depressions) from, the grooves.

Radiopaque markers represent that a lead is suitable for a particular medical procedure such as a magnetic resonance image scan and are added to the lead or related device. The markers may be added after implantation of the lead in various ways including suturing, gluing, crimping, or clamping a radiopaque tag to the lead or to the device. The markers may be added by placing a radiopaque coil about the lead, and the radiopaque coil may radially contract against the lead to obtain a fixed position. The markers may be added by placing a polymer structure onto the lead where the polymer structure includes a radiopaque marker within it. The polymer structure may include a cylindrical aperture that contracts against the lead to fix the position of the polymer structure. The polymer structure may form a lead anchor that includes suture wings that can be sutured to the lead.

A medical electrical lead includes a plurality of longitudinally spaced electrodes and a fixation element helix located between a proximal-most pair of adjacent electrodes of the plurality, so that a piercing tip of the helix is centered therebetween. A grip sleeve of a connector terminal of the lead may be gripped to apply a torque which is transferred to the fixation element, thereby engaging the helix thereof with tissue. The lead may include means for limiting the amount of torque that can be transferred from the connector terminal grip sleeve to the fixation element. The torque limiting means may be an external contour of the lead along a length thereof that extends between the connector terminal grip sleeve and the fixation element. The plurality of lead electrodes may further include a distal-most pair of adjacent electrodes, between which the lead extends in pre-set a curvature.

A lead anchor for a neuromodulation lead has an anchor body that receives a portion of the lead. A mesh is arranged so as to at least partially surround the portion of the lead when the portion of the lead is received in the anchor body.

A fixation mechanism of an implantable lead includes a plurality of depressions of an outermost surface of the lead and a relatively flexible sleeve mounted around the outermost surface. The depressions are spaced apart from one another along a length, and each extends circumferentially, wherein a longitudinal center-to-center spacing between each adjacent depression is uniform along the length, and each depression is of substantially the same size. The sleeve has an internal surface in sliding engagement with the outermost surface of the lead, and an external surface, in which suture grooves are formed. A longitudinal center-to-center spacing between adjacent suture grooves may be substantially the same as, or a multiple of, the longitudinal center-to-center spacing between adjacent depressions of the outermost surface of the lead. The sleeve may also include a ridge protruding from the internal surface, aligned with, or offset (by center-to-center spacing of depressions) from, the grooves.

Implantable medical leads and implantable lead extensions include a shield. The implantable medical lead is coupled to the implantable lead extension. Stimulation electrodes of the implantable medical lead contact stimulation connectors within a housing of the implantable extension to establish a conductive pathway for stimulation signals from filars of the implantable extension to filars of the implantable medical lead. Continuity is established between the shield of the implantable medical lead and the implantable extension by providing a radio frequency conductive pathway within the housing. The radio frequency conductive pathway extends from a shield of the implantable extension to a shield connector that contacts a shield electrode of the implantable medical lead. The radio frequency conductive pathway may have various forms such as a jumper wire or an extension of the shield within the implantable extension.

A shield located within an implantable medical lead may be terminated in various ways. The shield may be terminated by butt, scarf, lap, or other joints between insulation layers surrounding the lead and an insulation extension. For lap joints, a portion of an outer insulation layer may be removed and a replacement outer insulation layer is positioned in place of the removed outer insulation layer, where the replacement layer extends beyond an inner insulation layer and the shield. The replacement layer may also lap onto a portion of the insulation extension. Barbs may be located between the replacement layer and the inner insulation layer or the insulation extension. The shield wires have ends at the termination point that may be folded over individually or may be capped with a ring located within one of the insulation layers of the jacket.

A retention device for use with an implantable medical device (IMD) are disclosed. An illustrative retention device may comprise an elongate body including a configured to receive the lead of the IMD. The retention device may also include securing mechanisms coupled to the elongate body and configured to push against tissue of a patient. The securing mechanisms may also include linking elements coupled to the elongate body and a portion of the securing mechanisms.