Vijayeswaran N, Venkatesh Raju, Murugesan G, Balamurugan S, Indunesh K, Pradeep T T
Department of Neurosurgery, Coimbatore Medical College and Hospital, Coimbatore, Tamil Nadu, India.
J Neurosci Rural Pract. 2019 Apr-Jun;10(2):256-260. doi: 10.4103/jnrp.jnrp_183_18.
Pedicle screw fixation is one of the widely used procedures for instrumentation and stabilization of the thoracic and lumbar spine. It has the advantage of stabilizing all the three columns in single approach. Various assistive techniques are available to place the pedicle screws more accurately but at the expense of increased exposure to radiation, prolonged surgical duration, and cost.
The objective of this study is to determine the accuracy and safety of pedicle screw fixation in the thoracolumbar spine using freehand surgical technique.
We evaluated all patients who underwent pedicle screw fixation of the thoracolumbar spine for various ailments at our institute from January 2016 to December 2017 with postoperative computed tomography scan for placement accuracy. We used Gertzbein classification to grade pedicle breaches. Screw penetration more than 4 mm was taken as critical and those less than that were classified as noncritical.
A total of 256 screws inserted in T1-L5 vertebrae were included from 40 consecutive patients. Six screws were excluded according to selection criteria. The mean age was 39 years. Trauma (36 patients) was the common reason for which the pedicle screw fixation was done followed by degenerative disease (2 patients) and tumour (2 patients). A total of ten pedicle screw breaches (4%) were identified in eight patients. Among these, three critical breaches (1.2%) were occurred in two patients which required revision. The remaining seven breaches were noncritical and kept under close observation and follow-up.
Pedicle screw had become the workhorse of posterior stabilization of the spine. Based on external anatomy and landmarks alone, freehand technique for pedicle screw fixation can be performed with acceptable safety and accuracy avoiding cumulative radiation exposure and prolonged operative time.
椎弓根螺钉固定术是胸腰椎器械内固定和稳定手术中广泛应用的方法之一。其优点是通过单一入路可稳定脊柱的三柱结构。有多种辅助技术可更精确地置入椎弓根螺钉，但代价是增加了辐射暴露、延长了手术时间并增加了费用。
本研究的目的是确定徒手手术技术在胸腰椎椎弓根螺钉固定中的准确性和安全性。
我们评估了2016年1月至2017年12月在我院因各种疾病接受胸腰椎椎弓根螺钉固定术的所有患者，并通过术后计算机断层扫描评估螺钉置入的准确性。我们使用Gertzbein分类法对椎弓根穿破情况进行分级。螺钉穿透超过4mm被视为严重穿破，小于4mm则被分类为非严重穿破。
连续40例患者中，共纳入了在T1-L5椎体置入的256枚螺钉。根据选择标准排除6枚螺钉。平均年龄为39岁。创伤（36例患者）是进行椎弓根螺钉固定的常见原因，其次是退行性疾病（2例患者）和肿瘤（2例患者）。共在8例患者中发现10处椎弓根螺钉穿破（4%）。其中，2例患者出现3处严重穿破（1.2%），需要进行翻修。其余7处穿破为非严重穿破，进行密切观察和随访。
椎弓根螺钉已成为脊柱后路稳定手术的主要手段。仅基于外部解剖结构和体表标志，徒手进行椎弓根螺钉固定技术可在可接受的安全性和准确性下完成，避免了累积辐射暴露和手术时间延长。
