Lonner Baron, Verma Kushagra, Roonprapunt Chanland, Ren Yuan, Slattery Casey A, Alanay Ahmet, Kassin Gabrielle, Castillo Andrea, Bazerbashi Mohamad, Buehler Mark A, Kodigudla Manoj K, Kelkar Amey V, Serhan Hassan, Goel Vijay
Mount Sinai Hospital, New York, New York.
Verma Spine, Los Alamitos, California.
Int J Spine Surg. 2021 Apr;15(2):315-323. doi: 10.14444/8041. Epub 2021 Apr 1.
This study evaluates the accuracy, biomechanical profile, and learning curve of the transverse process trajectory technique (TPT) compared to the straightforward (SF) and in-out-in (IOI) techniques. SF and IOI have been used for fixation in the thoracic spine. Although widely used, there are associated learning curves and symptomatic pedicular breaches. We have found the transverse process to be a reproducible pathway into the pedicle.
Three surgeons with varying experience (experienced [E] with 20 years in practice, surgeon [S] with less than 10 years in practice, and senior resident trainee [T] with no experience with TPT) operated on 8 cadavers. In phase 1, each surgeon instrumented 2 cadavers, alternating between TPT and SF from T1 to T12 (n = 48 total levels). In phase 2, the E and T surgeons instrumented 1 cadaver each, alternating between TPT and IOI. Computed tomography scans were analyzed for accuracy of screw placement, defined as the percentage of placements without critical breaches. Axial pullout and derotational force testing were performed. Statistical analyses include paired test and analysis of variance with Tukey correction.
Overall accuracy of screw placement was comparable between techniques (TPT: 92.7%; SF: 97.2%; IOI: 95.8%; = .4151). Accuracy by technique did not differ for each individual surgeon (E: = .7733; S: = .3475; T: = .4191) or by experience level by technique (TPT: = .1127; FH: = .5979; IOI: = .5935). Pullout strength was comparable between TPT and SF (571 vs 442 N, = .3164) but was greater for TPT versus IOI (454 vs 215 N, = .0156). There was a trend toward improved derotational force for TPT versus SF (1.06 vs 0.93 Nm/degrees, = .0728) but not for TPT versus IOI (1.36 vs 1.16 Nm/degrees, = .74). Screw placement time was shortest for E and longest for T for TPT and SF and not different for IOI (TPT: = .0349; SF: < .0001; IOI: = .1787) but did not vary by technique.
We describe the TPT, which uses the transverse process as a corridor through the pedicle. TPT is an accurate method of thoracic pedicle screw placement with potential biomechanical advantages and with acceptable learning curve characteristics.
This study provides the surgeon with a new trajectory for pedicle screw placement that can be used in clinical practice.
本研究评估了横突入路技术（TPT）与直接入路（SF）和进出-进出入路（IOI）技术相比的准确性、生物力学特征和学习曲线。SF和IOI已用于胸椎固定。尽管广泛使用，但存在相关的学习曲线和有症状的椎弓根穿孔。我们发现横突是进入椎弓根的可重复路径。
三名经验不同的外科医生（有20年实践经验的经验丰富者[E]、实践经验少于10年的外科医生[S]和无TPT经验的高级住院医师实习生[T]）对8具尸体进行手术。在第1阶段，每位外科医生为2具尸体进行器械操作，从T1到T12在TPT和SF之间交替进行（共48个节段）。在第2阶段，E和T外科医生分别为1具尸体进行器械操作，在TPT和IOI之间交替进行。对计算机断层扫描进行分析，以评估螺钉置入的准确性，定义为无严重穿孔的置入百分比。进行轴向拔出和抗旋转力测试。统计分析包括配对t检验和采用Tukey校正的方差分析。
各技术之间螺钉置入的总体准确性相当（TPT：92.7%；SF：97.2%；IOI：95.8%；P = 0.4151）。每种技术的准确性在每位个体外科医生中无差异（E：P = 0.7733；S：P = 0.3475；T：P = 0.4191），或按技术的经验水平也无差异（TPT：P = 0.1127；FH：P = 0.5979；IOI：P = 0.5935）。TPT和SF之间的拔出强度相当（571对442 N，P = 0.3164），但TPT与IOI相比更大（454对215 N，P = 0.0156）。TPT与SF相比有抗旋转力改善的趋势（1.06对0.93 Nm/度，P = 0.0728），但TPT与IOI相比无此趋势（1.36对1.16 Nm/度，P = 0.74）。TPT和SF中，E的螺钉置入时间最短，T最长，IOI中无差异（TPT：P = 0.0349；SF：P < 0.0001；IOI：P = 0.1787），但未因技术而异。
我们描述了TPT，它利用横突作为穿过椎弓根的通道。TPT是一种准确的胸椎椎弓根螺钉置入方法，具有潜在的生物力学优势和可接受的学习曲线特征。
本研究为外科医生提供了一种可用于临床实践的椎弓根螺钉置入新路径。
