DOI: https://dx.doi.org/10.18203/issn.2455-4510.IntJResOrthop20222709
Published: 2022-10-27

New classification of S1 pedicle morphometry impacting pedicle screw insertion technique

Atit Tiwari, Sandeep V. Sonone, Nishant P. Jaiswal

Abstract


Background: The conventional entry point for the S1 pedicle screw insertion has been described as ‘at the base of and lateral to the superior S1 superior facet’. However, many orthopaedic surgeons complain that this technique is extremely demanding and is faced with many challenges in execution. Therefore, alternative entry points and modifications of existing techniques are explored for a greater convenience.

Methods: We conducted a survey amongst 136 spine surgeons on the technical difficulties faced during insertion of the S1 pedicle screw. We also classified the S1 pedicles based by measuring their geometric parameters on 100 random computed tomography (CT) images.

Results: The S1 pedicle entry technique was considered to be the most difficult and challenging by the orthopaedic surgeons in our survey due to an inadequate medial angulation due to paraspinal muscle mass tension and an overhanging iliac crest. This could be explained by the hourglass shaped pedicle (type 3) with a desired medial angle more 50 degrees (type III) observed as the most common S1 pedicle in the study population. To overcome this limitation, most of them preferred a tri-corticate approach.

Conclusions: A more lateral entry point and a longer screw might be considered as solutions for a better and safer S1 pedicle entry. Also, the use of pre-operative CT can be considered to visualize the type of S1 pedicle and hence, decide on the most appropriate technique of screw insertion.

 


Keywords


S1, Pedicle shape, Hourglass, Chord length, Entry point, Iliac overhang

Full Text:

PDF

References


Kornblatt MD, Casey MP, Jacobs RR. Internal fixation in lumbosacral spine fusion. A biomechanical and clinical study. Clin Orthop Relat Res. 1986;(203):141-50.

Resnick DK, Choudhri TF, Dailey AT, Groff MW, Khoo L, Matz PG et al. Guidelines for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 7: intractable low-back pain without stenosis or spondylolisthesis. J Neurosurg Spine. 2005;2(6):670-2.

Sevrain A, Aubin CE, Gharbi H, Wang X, Labelle H. Biomechanical evaluation of predictive parameters of progression in adolescent isthmic spondylolisthesis: a computer modelling and simulation study. Scoliosis. 2012;7(1):2.

Mobbs RJ, Phan K, Malham G, Seex K, Rao PJ. Lumbar interbody fusion: techniques, indications and comparison of interbody fusion options including PLIF, TLIF, MI-TLIF, OLIF/ATP, LLIF and ALIF. J Spine Surg. 2015;1(1):2-18.

Reid PC, Morr S, Kaiser MG. State of the union: a review of lumbar fusion indications and techniques for degenerative spine disease. J Neurosurg Spine SPI. 2019;31(1):1-14.

Sorour I, Elbary MA, Rabie A, Elhabashy AM. An early experience of lumbopelvic fixation techniques at Alexandria University. Egypt J Neurosurg. 2021;36:11.

Kubaszewski L, Nowakowski A, Kaczmarczyk J. Evidence-based support for S1 transpedicular screw entry point modification. J Orthop Surg Res. 2014;9:22.

Carlson GD, Abitbol JJ, Anderson DR, Krag MH, Kostuik JP, Woo SL et al. Screw fixation in the human sacrum. An in vitro study of the biomechanics of fixation. Spine (Phila Pa 1976). 1992;17(6):S196-203.

Smith SA, Abitbol JJ, Carlson GD, Anderson DR, Taggart KW, Garfin SR. The effects of depth of penetration, screw orientation, and bone density on sacral screw fixation. Spine (Phila Pa 1976). 1993;18(8):1006-10.

Roy-Camille R, Saillant G, Mazel C. Internal fixation of the lumbar spine with pedicle screw plating. Clin Orthop Relat Res. 1986;(203):7-17.

Lee YP, Ihn HE, McGarry MH, Farhan SD, Bhatia N, Lee TQ. Biomechanical Analysis of an S1 Pedicle Screw Salvage Technique via a Superior Articulating Process Entry Point. Spine (Phila Pa 1976). 2016;41(13): E778-84.

Hoel RJ, Ledonio CG, Takahashi T, Polly DW Jr. Sacral bone mineral density (BMD) assessment using opportunistic CT scans. J Orthop Res. 2017;35(1):160-66.

Mobbs RJ, Sivabalan P, Li J. Technique, challenges and indications for percutaneous pedicle screw fixation. J Clin Neurosci. 2011;18(6):741-9.

Babu R, Park JG, Mehta AI, Shan T, Grossi PM, Brown CR et al. Comparison of superior-level facet joint violations during open and percutaneous pedicle screw placement. Neurosurgery. 2012;71(5):962-70.

Weinstein JN, Rydevik BL, Rauschning W. Anatomic and technical considerations of pedicle screw fixation. Clin Orthop Relat Res. 1992;34-46.

Merloz P, Troccaz J, Vouaillat H, Vasile C, Tonetti J, Eid A et al. Fluoroscopy-based navigation system in spine surgery. Proc Inst Mech Eng H. 2007;221(7):813-20.

Zhou SH, McCarthy ID, McGregor AH, Coombs RR, Hughes SP. Geometrical dimensions of the lower lumbar vertebrae--analysis of data from digitised CT images. Eur Spine J. 2000;9(3):242-8.

Katsuura Y, Chang E, Sabri SA, Gardner WE, Doty JF. Anatomic Parameters for Instrumentation of the Sacrum and Pelvis: A Systematic Review of the Literature. J Am Acad Orthop Surg Glob Res Rev. 2018;2(8):e034.

Kato M, Taneichi H, Suda K. Advantage of pedicle screw placement into the sacral promontory (tricortical purchase) on lumbosacral fixation. J Spinal Disord Tech. 2015;28(6):E336-42.

Le Cann S, Cachon T, Viguier E, Miladi L, Odent T, Rossi JM et al. Pedicle Screw Fixation Study in Immature Porcine Spines to Improve Pullout Resistance during Animal Testing. PLoS One. 2015;10(10):e0127463.

Chua MJ, Siddiqui S, Yu CS, Nolan CP, Oh JY. The Optimal Screw Length of Lumbar Pedicle Screws during Minimally Invasive Surgery Fixation: A Computed Tomography-Guided Evaluation of 771 Screws. Asian Spine J. 2019;13(6):936-41.

Carlson DA, Scheid DK, Maar DC, Baele JR, Kaehr DM. Safe placement of S1 and S2 iliosacral screws: the quot; vestibule" concept. J Orthop Trauma. 2000;14(4):264-9.

Amato V, Giannachi L, Irace C, Corona C. Accuracy of pedicle screw placement in the lumbosacral spine using conventional technique: computed tomography postoperative assessment in 102 consecutive patients. J Neurosurg Spine. 2010;12(3):306-13.

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. 2012;21(2):247-55.

Soriano-Sánchez JA, Ortega-Porcayo LA, Gutiérrez-Partida CF, Ramírez-Barrios LR, Ortíz-Leyva RU, Rodríguez-García M et al. Fluoroscopy-guided pedicle screw accuracy with a mini-open approach: a tomographic evaluation of 470 screws in 125 patients. Int J Spine Surg. 2015;9:54.

Yoshii T, Hirai T, Yamada T, Sumiya S, Mastumoto R, Kato T, et. al. Lumbosacral pedicle screw placement using a fluoroscopic pedicle axis view and a cannulated tapping device. J Orthop Surg Res. 2015;10:79.

Klein S, Whyne CM, Rush R, Ginsberg HJ. CT-based patient-specific simulation software for pedicle screw insertion. J Spinal Disord Tech. 2009;22(7):502-6.