Patent ID: 8668719

Claim:
A method for improving shear loading capacity of a spinal segment, the spinal segment having a superior vertebra, a superior spinous process on the superior vertebra, an inferior vertebra, an inferior spinous process on the inferior vertebra, or a sacrum, and a facet joint therebetween, said method comprising: providing a constraint device having an upper portion, a lower portion and a compliance member coupled therebetween, wherein the upper portion comprises a flexible and non-distensible tether, and wherein the lower portion comprises a flexible and non-distensible tether; coupling the constraint device with the spinal segment, wherein the flexible and non-distensible tether of the upper portion of the constraint device is disposed around a superior surface of the superior spinous process and the flexible and non-distensible tether of the lower portion of the constraint device is disposed around an inferior surface of the inferior spinous process or coupled to the sacrum, and wherein the constraint device provides a force resistant to flexion of the spinal segment without substantially restricting extension; and adjusting length or tension in the constraint device so as to increase engagement between an upper portion of the facet joint and a lower portion of the facet joint, thereby increasing capacity of the spinal segment to resist shear loading, and reducing or eliminating further progression of degenerative spondylolisthesis in the spinal segment without fusion thereof.