Department of Spinal Surgery, General Hospital of Ningxia Medical University, Yinchuan, China; Department of Spine Surgery, The Third Affiliated Hospital of Chongqing Medical University (General Hospital), Chongqing, China.
Department of Orthopedics, Three Gorges Central Hospital, Chongqing, China.
World Neurosurg. 2019 May;125:e435-e441. doi: 10.1016/j.wneu.2019.01.100. Epub 2019 Jan 30.
To observe anatomic relationships between lumbar bicortical pedicle screws (BPSs) at 2 sagittal section angles (SSAs) and lumbar artery (LA).
We observed 2 SSAs, vertical angle and cephalic angle, of the BPS. The positions at which the BPS breaks through the anterior vertebral cortex were defined as point A and point B. Distances from point A and point B to LAs were measured. The percentage of risk of injury to LAs was calculated according to these distances.
At the same transverse section angle on the left and right side in L1 and L2, distance from point A to LA was significantly greater than distance from point B to LA (P < 0.001) except at a transverse section angle of 0° on the right side in L2 (P > 0.05). At the same transverse section angle on the left in L3 and L4, distance from point B to LA was significantly greater than distance from point A to LA (P < 0.001). The percentages of high risk of injury to the LA resulting from BPSs at the vertical angle in L1 and L2 were 0%-6.2%. The percentages of high risk of injury to the LA resulting from BPSs at the cephalic angle on the left side in L3 and L4 were 0%-18.5%.
Lumbar BPSs present a risk of injury to the LA. The vertical angle is the recommended SSA for BPSs in L1 and L2, and the cephalic angle is the recommended SSA in L3 and L4.
观察两种矢状面角度（SSA）下腰椎双皮质椎弓根螺钉（BPS）与腰动脉（LA）的解剖关系。
观察 BPS 的两个 SSA，即垂直角和头倾角。将 BPS 突破前侧皮质的位置定义为 A 点和 B 点。测量 A 点和 B 点到 LA 的距离。根据这些距离计算 LA 损伤风险的百分比。
在 L1 和 L2 的左右两侧相同的横断面上，A 点到 LA 的距离明显大于 B 点到 LA 的距离（P < 0.001），除了 L2 右侧的 0°横断面上（P > 0.05）。在 L3 和 L4 的左侧相同的横断面上，B 点到 LA 的距离明显大于 A 点到 LA 的距离（P < 0.001）。在 L1 和 L2 的垂直角处，BPS 对 LA 造成高度损伤的风险百分比为 0%-6.2%。在 L3 和 L4 的左侧头倾角处，BPS 对 LA 造成高度损伤的风险百分比为 0%-18.5%。
腰椎 BPS 存在损伤 LA 的风险。垂直角是 L1 和 L2 中推荐的 BPS SSA，头倾角是 L3 和 L4 中推荐的 BPS SSA。
