Accuracy Assessment of Freehand Pedicular Screw Placement

Document Type : RESEARCH PAPER


Bahonar Hospital, School of Medicine, Kerman University of Medcal Science, Kerman, Iran


Background: The purpose of this prospective study was to determine the accuracy of pedicular screw insertion without
the use of fluoroscopy.
Methods: This study was conducted on patients with spinal diseases in need of pedicular screw fixation and fusion.
The included patients suffered from such conditions as vertebral fracture, spinal stenosis, kyphosis, tumor, and pelvic
fractures and were managed with triangular osteosynthesis fixation. However, those with scoliosis deformity were
excluded from the study. A total of 760 pedicular screws were inserted in C7 to S1 vertebrae without using fluoroscopy.
The locations of the screws were assessed by means of computed tomography scan after the surgery. The data were
analyzed in SPSS software (version 22) using the Chi-square test.
Results: Out of 387 thoracic screws and 373 lumbar screws, 65 (16.8%) and 34 (9.1%) screws perforated the pedicle
wall or vertebral body, respectively. The most frequent locations of perforation in the thoracic and lumbar spine were
the anterior cortex of the vertebral body and medial wall of the pedicle, respectively. Except for the perforation of the
anterior vertebral body (P=0.0001), there was no difference between the left and right sides or between thoracic and
lumbar sites in terms of the preformation of the screw. No complication was observed due to screw perforation.
Conclusion: Our findings revealed the unnecessity of using fluoroscopy in spine surgeries for the insertion of pediculate
screws. In this regard, the use of fluoroscopy for the placement of pedicular screw resulted in similar accuracy and
complications, as compared to the free hand procedure.
Level of evidence: I


1. Heshmati AA, Mirzaee M. Reliability and validity of
the swiss spinal stenosis questionnaire for Iranian
patients with lumbar spinal stenosis. Arch Bone Jt
Surg. 2018; 6(2):119-23.
2. Ghandhari H, Ameri E, Vahidtari H, Mobini B,
Behtash H, Heshmati AA. The association between
intermittent neurogenic claudication and spinal
sagittal balance in patients with lumbar canal
stenosis: a prospective study. J Res Orthop Sci. 2013;
3. Verlaan JJ, Diekerhof CH, Buskens E, van der Tweel
I, Verbout AJ, Dhert WJ, et al. Surgical treatment of
traumatic fractures of the thoracic and lumbar spine:
a systematic review of the literature on techniques,
complications, and outcome. Spine (Phila Pa 1976).
2004; 29(7):803-14.
4. Gertzbein SD, Robbins SE. Accuracy of pedicular
screw placement in vivo. Spine. 1990; 15(1):11-4.
5. Kamimura M, Ebara S, Itoh H, Tateiwa Y, Kinoshita T,
Takaoka K. Accurate pedicle screw insertion under
the control of a computer-assisted image guiding
system: laboratory test and clinical study. J Orthop
Sci. 1999; 4(3):197-206.
6. Laine T, Mäkitalo K, Schlenzka D, Tallroth K, Poussa
M, Alho A. Accuracy of pedicle screw insertion: a
prospective CT study in 30 low back patients. Eur
Spine J. 1997; 6(6):402-5.
7. Upendra BN, Meena D, Chowdhury B, Ahmad
A, Jayaswal A. Outcome-based classification for
assessment of thoracic pedicular screw placement.
Spine. 2008; 33(4):384-90.
8. Dinesh SK, Tiruchelvarayan R, Ng I. A prospective 
study on the use of intraoperative computed
tomography (iCT) for image-guided placement
of thoracic pedicle screws. Br J Neurosurg. 2012;
9. Peter O. Newton SJL. Thoracolumbar spine fractures.
In: John M, Flynn DL, Peter M, editor. Rockwood
fracture in adults. 8th ed. Philadelphia: Wolters
Kluwer Health; 2015. P. 901-17.
10. William C, Warner JR. Scoliosis and kyphosis.
In: Terry Canale M, editor. Campbell’s operative
orthopaedics. 13th ed. Philadelphia: Mosby; 2017. P.
11. Bogduk N. Clinical anatomy of the lumbar spine and
sacrum. New York: Elsevier Health Sciences; 2005.
12. 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.
13. Ameri E, Ghandhari H, Vahidtari H, Behtash H, Mobini
B, Ganjavian M, et al. Correlation between kyphosis
and flexibility of kyphoscoliosis curves. J Adv Med
Biomed Res. 2012; 20(80):115-22.
14. Aoude AA, Fortin M, Figueiredo R, Jarzem P, Ouellet
J, Weber MH. Methods to determine pedicle screw
placement accuracy in spine surgery: a systematic
review. Eur Spine J. 2015; 24(5):990-1004.
15. Castro WH, Halm H, Jerosch J, Malms J, Steinbeck J,
Blasius S. Accuracy of pedicle screw placement in
lumbar vertebrae. Spine. 1996; 21(11):1320-4.
16. Weinstein JN, Spratt KF, Spengler D, Brick C, Reid 
S. Spinal pedicle fixation: reliability and validity
of roentgenogram-based assessment and surgical
factors on successful screw placement. Spine. 1988;
17. Sim E. Location of transpedicular screws for fixation
of the lower thoracic and lumbar spine: computed
tomography of 45 fracture cases. Acta Orthop Scand.
1993; 64(1):28-32.
18. Williams KD. Fractures, dislocations, and fracturedislocations
of the spine. In: Frederick M, Azar
JH, Terry Canale S, editor. Campbell’s operative
orthopaedics. 13th ed. Philadelphia: Elsevier; 2017.
P. 1756-814.
19. Yahiro MA. Comprehensive literature review: pedicle
screw fixation devices. Spine. 1994; 19(20):2274S-8S.
20. Suk SI, Kim WJ, Lee SM, Kim JH, Chung ER. Thoracic
pedicle screw fixation in spinal deformities: are they
really safe? Spine. 2001; 26(18):2049-57.
21. Liljenqvist UR, Halm HF, Link TM. Pedicle screw
instrumentation of the thoracic spine in idiopathic
scoliosis. Spine. 1997; 22(19):2239-45.
22. Belmont PJ Jr, Klemme WR, Dhawan A, Polly DW Jr.
In vivo accuracy of thoracic pedicle screws. Spine.
2001; 26(21):2340-6.