Spine
-
Comparative Study
Biomechanical testing of posterior atlantoaxial fixation techniques.
An in vitro biomechanical study of C1-C2 posterior fusion techniques was conducted using a cadaveric model. ⋯ The results clearly indicate the screw-rod system's equivalence in reducing relative atlantoaxial motion in a severely destabilized upper cervical spine, as compared with the transarticular screw-wiring construct. These findings mirror the previously reported clinical results attained using this new screw-rod construct. Thus, the decision to use either screw construct should be based on safety considerations rather than acute stability.
-
An anatomic study of pedicle dimensions and orientation was performed for upper thoracic vertebrae from elderly human subjects. ⋯ Even the largest patients had some pedicles that could not accommodate the smallest standard pedicle screw, and more than one half of the pedicles average patients were too small. Transpedicular screw placement is not safe in these patients. Proper placement must avoid penetration of the medial pedicle wall.
-
A literature review and synthesis were performed. ⋯ Some clinical or experimental support can be found in the literature for 10 specific mechanisms or proposed mechanisms of spinal cord stimulation.
-
A randomized comparison of conventional and image-guided technology techniques for pedicle screw placement was performed. ⋯ Accuracy of pedicle screw placement in the thoracolumbosacral spine is improved with the use of image-guided methods, particularly guidance by computed tomography. This is especially relevant clinically when the anatomy is obscured or altered as a result of inflammatory spondyloarthropathy (e.g., ankylosing spondylitis in which spontaneous fusions obscure surgical landmarks for pedicle access), or when used postsurgically in the setting of a posterolateral fusion.
-
The literature on diagnostic tests available to the spine clinician for the evaluation of chronic low back pain was reviewed. ⋯ There are inherent limitations in the accuracy of all diagnostic tests. The tests used to diagnose the source of a patient's chronic low back pain require accurate determination of the abolition or reproduction of the patient's painful symptoms.