Elfiky Tarek Anwar, Patil Nirmal Dhananjay, Luk Keith Dk, Faheem Mohamed Esam, Samartzis Dino
Spine Unit, Al-Hadra University Hospital, Alexandria, Egypt.
Department of Orthopaedics, Seth GS Medical College and KEM Hospital, Mumbai, India.
Asian Spine J. 2021 Feb;15(1):81-88. doi: 10.31616/asj.2019.0114. Epub 2020 Feb 14.
Retrospective radiographic study.
We hypothesized that the pedicle is almost perpendicular to the interlaminar line in the sagittal plane of the lumbar vertebrae. The current study aimed to define the lumbar lamina-pedicle inclination to verify the right-angle concept and to estimate the safety zones of sagittal inclination during pedicle screw insertion. To the best of our knowledge there are no previous similar studies.
Based on our observations in different spinal disorders including deformities, we noted that following a sagittal (cranial-caudal) trajectory perpendicular to the interlaminar line joining the two adjacent vertebrae would work well in most of the vertebral levels.
This was a retrospective study on normal lumbar spine lateral radiographs of patients who presented with low back pain and were reviewed by two observers. Different inclination angles were constructed to estimate the safety zones of the pedicle screws' sagittal inclination.
Radiographs of 30 consecutive patients, 25 females and five males, with a mean age of 39.43±11.18 years, were studied. The mean angle of the interlaminar line and the pedicle axis was almost orthogonal at all the levels, with a range of 89.16°-94.63°, which was not affected by the lumbar sagittal profile. The safety zones of the pedicle screws were measured, and they revealed a safe sagittal range of 19.73°-24.40° if the screw was inserted from the pedicle axis, 21.03°-22.59° if inserted from the most cephalic part, and 13.31°-17.03° if inserted from the most caudal part.
Our results confirmed the perpendicularity of the interlaminar line with the pedicle axis in the lumbar spine at all the levels. The interlaminar line is a useful guide for pedicle screw sagittal inclination.
回顾性影像学研究。
我们假设在腰椎矢状面中椎弓根几乎垂直于椎板间线。本研究旨在确定腰椎椎板 - 椎弓根倾斜度，以验证直角概念，并估计椎弓根螺钉置入过程中矢状倾斜的安全区。据我们所知，此前尚无类似研究。
基于我们在包括畸形在内的不同脊柱疾病中的观察，我们注意到，在大多数椎体节段，沿着垂直于连接两个相邻椎体的椎板间线的矢状（头 - 尾）轨迹操作效果良好。
这是一项对因腰痛就诊患者的正常腰椎侧位X线片的回顾性研究，由两名观察者进行评估。构建不同的倾斜角度以估计椎弓根螺钉矢状倾斜的安全区。
对连续30例患者（25例女性，5例男性）的X线片进行研究，平均年龄为39.43±11.18岁。在所有节段，椎板间线与椎弓根轴线的平均角度几乎呈正交，范围为89.16° - 94.63°，不受腰椎矢状形态影响。测量了椎弓根螺钉的安全区，结果显示，如果螺钉从椎弓根轴线置入，矢状安全范围为19.73° - 24.40°；从最头侧部分置入时为21.03° - 22.59°；从最尾侧部分置入时为13.31° - 17.03°。
我们的结果证实了腰椎各节段椎板间线与椎弓根轴线的垂直性。椎板间线是椎弓根螺钉矢状倾斜的有用导向。
