Brown Mark D, Holmes David C, Heiner Anneliese D
Department of Orthopaedics and Rehabilitation, University of Miami School of Medicine, Miami, Florida 33101, USA.
Spine (Phila Pa 1976). 2002 May 1;27(9):918-22. doi: 10.1097/00007632-200205010-00006.
Prospective.
To measure lumbar spine motion segment stiffness and relate it to the degree of disc degeneration.
The association between the instability of the lumbar spine motion segment and disc degeneration remains unclear. The traditional method for determining motion segment instability at the time of decompressive surgery is a manual test performed by the surgeon. To quantify instability of the lumbar spine, a vertebrae distractor was developed in the authors' laboratory to measure motion segment stiffness by applying a defined load at a constant rate.
Lumbar stiffness was measured by subjecting cadaver lumbar spine motion segments to a constant rate flexion-traction load and recording the magnitude of the resistance to distraction versus the range of motion. Disc degeneration was measured by pressure-volume discography and by grading of disc morphology.
Motion segment stiffness decreased with the initial stages of disc degeneration and then increased with severe disc degeneration. This measure of motion segment stiffness correlated well with a manual stiffness measure.
The observed results follow an accepted hypothesis of motion segment instability associated with disc degeneration.
前瞻性研究。
测量腰椎运动节段的刚度，并将其与椎间盘退变程度相关联。
腰椎运动节段的不稳定与椎间盘退变之间的关联仍不明确。减压手术时确定运动节段不稳定的传统方法是由外科医生进行的手动测试。为了量化腰椎的不稳定性，作者所在实验室研发了一种椎骨撑开器，通过以恒定速率施加规定负荷来测量运动节段的刚度。
通过对尸体腰椎运动节段施加恒定速率的屈伸牵引负荷，并记录抗撑开阻力大小与运动范围，来测量腰椎刚度。通过压力-容积椎间盘造影和椎间盘形态分级来测量椎间盘退变。
运动节段刚度在椎间盘退变初期降低，然后在严重椎间盘退变时增加。这种运动节段刚度测量方法与手动刚度测量结果相关性良好。
观察结果符合与椎间盘退变相关联的运动节段不稳定的公认假说。
