Abstract:
Methods and devices for restricting movement of a spinal segment by providing an adjustable constraining device that includes a tether and a compliance member coupled together. The tether is coupled to a superior spinous process and an inferior spinous process or a sacrum so that the construct of the compliance member and tethers provides a force resistant to flexion and a force resistant to extension of a spinal segment. In some embodiments, the construct of the compliance member and tethers may provide only a force resistant to extension.
Abstract:
Methods, apparatus and systems for constraining spinous processes to elastically limit flexion of two or more adjacent spinal segments rely on placing a tether structure over at least three adjacent vertebral bodies or two adjacent vertebral bodies and the sacrum. The tether structures may be continuous, for example in the form of a continuous loop, or may be discontinuous, for example in the form of a loop or elongate element having at least two anchor structures for securing in bone.
Abstract:
Fastening mechanisms for releasably locking a tether are provided. The mechanisms find application with orthopedic internal-fixation implants and make the implants more reliable and their implantation less invasive. A method for releasably locking a tether comprises advancing the tether through a tether aperture in a clamp body. The tether enters the tether aperture in a first plane and exits in a second plane generally transverse to the first plane. Positioning a fastener element in a fastener aperture in the clamp body captures the tether between the clamp body and the fastener element thereby releasably locking the tether in position relative to the clamp body.
Abstract:
A spinal implant for limiting flexion of the spine includes a tether structure for encircling adjacent spinal processes. Usually, a pair of compliance members will be provided as part of the tether structure for elastically limiting flexion while permitting an extension. A cross-member is provided between the compliance member or other portions of the tether structure to stabilize the tether structure and prevent misalignment after implantation.
Abstract:
A surgical fastening mechanism for releasably locking an implantable tether includes a housing having a central channel. The housing has an entry aperture, an exit aperture and a side channel extending therebetween. A roller element has a sidewall with an aperture therethrough and the roller is slidably disposed at least partially in the central channel such that the entry and exit apertures are at least partially aligned with the roller aperture. This permits passage of the tether therethrough. Rotation of the roller element in a first direction winds the tether around the roller thereby creating a friction interface between the roller element, the housing and the tether. A locking mechanism is operably connected with either the housing or the roller element and is adapted to prevent rotation of the roller in the central channel and also adapted to prevent release of the tether from the roller.
Abstract:
Methods, apparatus and systems for constraining spinous processes to elastically limit flexion of two or more adjacent spinal segments rely on placing a tether structure over at least three adjacent vertebral bodies or two adjacent vertebral bodies and the sacrum. The tether structures may be continuous, for example in the form of a continuous loop, or may be discontinuous, for example in the form of a loop or elongate element having at least two anchor structures for securing in bone.
Abstract:
Spinous process constraint structures include a first attachment element for placement over a first spinous process and a second attachment element for placement over a second spinous process. The attachment elements are joined by a single connector which may optionally include a compliance member for providing controlled elasticity between the spinous processes.
Abstract:
A system for restricting spinal flexion includes superior and inferior tether structures joined by a pair of compliance members. Compliance members comprise tension members which apply a relatively low elastic tension on the tether structures. By placing the tether structures on or over adjacent spinous processes, flexion of a spinal segment can be controlled in order to reduce pain.
Abstract:
A spinal implant for limiting flexion of the spine includes a tether structure for encircling adjacent spinal processes. Usually, a pair of compliance members will be provided as part of the tether structure for elastically limiting flexion while permitting an extension. A cross-member is provided between the compliance member or other portions of the tether structure to stabilize the tether structure and prevent misalignment after implantation.