Background
Variations in the pedicle morphology and presence of spinal deformities can make pedicle screw placement challenging. Recently, computerized tomography (CT) guided screw placement has reportedly improved the surgical accuracy of pedicle screw insertion. However, it is time consuming and expensive. We combined single-plane fluoroscopy in AP projection alone with tactile guidance for placing pedicle screws more efficiently and accurately. This report presents our results with this technique.
Materials and Methods
An Institutional Review Board (IRB) approved retrospective study was carried out on 308 patients who underwent lumbar spinal fusion with 1806 pedicle screws placed using fluoroscopy only in the AP plane. There were 182 patients with two-level fusion, 79 with single-level fusion, 26 with three-level fusion, and 21 with more than three-level fusions. The indications of surgery included spondylolisthesis, adult scoliosis, revision surgery, lumbar canal stenosis, and discogenic pain. Pedicle screws were inserted under fluoroscopic guidance in the AP plane alone with a final lateral image after completion of implant placement. Radiographs were performed postoperatively in all patients and CT scans were obtained on 78 patients with 588 screws.
Results
Twenty nine (5%) cortical wall perforations were noted amongst the 588 screws that were evaluated with a CT scan and did not result in postoperative vascular or neural complications. Anterior cortical vertebral violation was noted in 14 patients, while in 9 patients the screws penetrated the lateral wall of the pedicle. The medial wall of the pedicle was encroached in six patients with no frank perforations.
Conclusion
Placement of pedicle screws under fluoroscopic guidance using AP plane imaging alone with tactile guidance is safe, fast, and reliable. However, a good understanding of the radiographic landmarks is a prerequisite.
Similar content being viewed by others
References
Park Y, Ha JW, Lee YT, Sung NY. Percutaneous placement of pedicle screws in overweight and obese patients. Spine J 2011;11:919–24.
Gelalis ID, Paschos NK, Pakos EE, Politis AN, Arnaoutoglou CM, Karageorgos AC, et al. Accuracy of pedicle screw placement: a systematic review of prospective in vivo studies comparing free hand, fluoroscopy guidance and navigation techniques. Eur Spine J 2011;21:247–55.
Chang KW, Wang YF, Zhang GZ, Cheng CW, Chen HY, Leng X, et al. Tai Chi. Pedicle screw placement for severe scoliosis. J Spinal Disord Tech 2011;25:E67–73.
Wood M, Mannion R. A comparison of CT-based navigation techniques for minimally invasive lumbar pedicle screw placement. J Spinal Disord Tech 2011;24:E1–5.
Silbermann J, Riese F, Allam Y, Reichert T, Koeppert H, Gutberlet M. Computer tomography assessment of pedicle screw placement in lumbar and sacral spine: Comparison between free-hand and O-arm based navigation techniques. Eur Spine J 2011;20:875–81.
Desai S, Sethi A, Ninh CC, Bartol S, Vaidya R. Pedicle screw fixation of the C7 vertebra using an anteroposterior fluoroscopic imaging technique. Eur Spine J 2010;19:1953–9.
Learch TJ, Massie JB, Pathria MN, Ahlgren BA, Garfin SR. Assessment of pedicle screw placement utilizing conventional radiography and computed tomography: a proposed systematic approach to improve accuracy of interpretation. Spine (Phila Pa 1976). 2004;29:767–73.
Wiesner L, Kothe R, Rüther W. Anatomic evaluation of two different techniques for the percutaneous insertion of pedicle screws in the lumbar spine. Spine (Phila Pa 1976). 1999;24:1599–603.
Castro WH, Halm H, Jerosch J, Malms J, Steinbeck J, Blasius S. Accuracy of pedicle screw placement in lumbar vertebrae. Spine (Phila Pa 1976) 1996;21:1320–4.
Gertzbein SD, Robbins SE. Accuracy of pedicular screw placement in vivo. Spine (Phila Pa 1976) 1990;15:11–4.
Vaidya R, Carp J, Bartol S, Ouellette N, Lee S, Sethi A. Lumbar spine fusion in obese and morbidly obese patients. Spine (Phila Pa 1976) 2009;34:495–500.
Kim MC, Chung HT, Cho JL, Kim DJ, Chung NS. Factors affecting the accurate placement of percutaneous pedicle screws during minimally invasive transforaminal lumbar interbody fusion. Eur Spine J 2011;20:1635–43.
Sterba W, Kim DG, Fyhrie DP, Yeni YN, Vaidya R. Biomechanical analysis of differing pedicle screw insertion angles. Clin Biomech (Bristol, Avon) 2007;22:385–91.
Zindrick MR, Wiltse LL, Doornik A, Widell EH, Knight GW, Patwardhan AG, et al. Analysis of the morphometric characteristics of the thoracic and lumbar pedicles. Spine (Phila Pa 1976) 1987;12:160–6.
Yoo JU, Ghanayem A, Petersilge C, Lewin J. Accuracy of using computed tomography to identify pedicle screw placement in cadaveric human lumbar spine. Spine (Phila Pa 1976) 1997;22:2668–71.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Sethi, A., Lee, A. & Vaidya, R. Lumbar pedicle screw placement: Using only AP plane imaging. IJOO 46, 434–438 (2012). https://doi.org/10.4103/0019-5413.98832
Published:
Issue Date:
DOI: https://doi.org/10.4103/0019-5413.98832