Orthopaedic Research Center at Orthopaedic Hospital/University of California Los Angeles, Los Angeles, CA 90007, USA.
Spine (Phila Pa 1976). 2011 Sep 1;36(19):E1251-8. doi: 10.1097/BRS.0b013e318206cd84.
A biomechanical study using human cadaveric lumbar spinal motion segments and three different posterior stabilization devices.
To compare the range of motion, disc height, and foraminal area of a spinal motion segment intact, injured, and fixed with each of three posterior lumbar motion preservation devices.
Motion-sparing lumbar posterior dynamic stabilization devices are gaining increasing popularity, particularly for the treatment of degenerative disc disease.
The PercuDyn, the X-Stop, and the Isobar posterior stabilization devices were compared using an in vitro cadaveric model. First, pure moments of ±8 Nm were applied in all three planes, then a follower load of 700 N was applied, and finally, sagittal bending tests were repeated. All tests were conducted using an 8-df servohydraulic load frame. Experiments were performed intact, with a simulated injury, and then with each of the three devices for a total of four specimens per device. Foraminal area and disc height (posterolateral and anterior surface) were measured under neutral and peak torques in all three planes and range of motion was recorded for all experimental conditions.
Overall, the injury model successfully increased range of motion and decreased disc height and foraminal area. Once treated with one of the three implants, the PercuDyn was most effective at preventing hyperextension, decreasing extension with a follower load by a mean of 52% compared to injured conditions (P = 0.07). The X-Stop stabilized the posterior column, increasing foraminal area under all conditions, particularly extension with a follower load, by 27% compared to injured conditions (P = 0.01). The Isobar, the only device to stabilize the anterior column, increased anterior disc height under flexion with a follower load by 22% (P = 0.03).
All three devices functioned as intended by their respective manufacturers, but each appeared to excel in different areas; therefore, each should be used for unique clinical applications.
一项使用人体腰椎运动节段和三种不同后路稳定装置的生物力学研究。
比较完整、损伤和用三种后路腰椎运动保留装置固定的运动节段的活动范围、椎间盘高度和椎间孔面积。
保留运动的腰椎后路动态稳定装置越来越受欢迎，特别是在退行性椎间盘疾病的治疗中。
使用体外尸体模型比较 PercuDyn、X-Stop 和 Isobar 后路稳定装置。首先，在所有三个平面施加±8 Nm 的纯力矩，然后施加 700 N 的跟随力，最后重复矢状弯曲试验。所有试验均在 8 自由度伺服液压加载框架上进行。实验在完整、模拟损伤以及三种装置各进行一次，每个装置共进行 4 个标本。在所有三个平面上，在中立和峰值扭矩下测量椎间孔面积和椎间盘高度（后外侧和前表面），并记录所有实验条件下的活动范围。
总体而言，损伤模型成功地增加了活动范围，降低了椎间盘高度和椎间孔面积。一旦用三种植入物之一进行治疗，PercuDyn 最有效地防止过度伸展，在跟随力下减少伸展，与损伤状态相比平均减少 52%（P = 0.07）。X-Stop 稳定了后柱，在所有条件下增加了椎间孔面积，特别是在跟随力下的伸展，与损伤状态相比增加了 27%（P = 0.01）。Isobar 是唯一稳定前柱的装置，在跟随力下增加了前椎间盘高度，增加了 22%（P = 0.03）。
所有三种装置都按照各自制造商的意图发挥作用，但每种装置似乎在不同的领域表现出色；因此，每种装置都应用于独特的临床应用。
