A Comparison of Three Different Positioning Techniques on Surgical Corrections and Postoperative Alignment in Cervical Spinal Deformity (CD) Surgery.


Study design

Retrospective review of a prospective multicenter cervical deformity database.


To examine the differences in sagittal alignment correction between three positioning methods in cervical spinal deformity surgery (CD).

Summary of background data

Surgical correction for CD is technically demanding and various techniques are utilized to achieve sagittal alignment objectives. The effect of different patient positioning techniques on sagittal alignment correction following CD remains unknown.


Patients with sagittal deformity who underwent a posterior approach (with and without anterior approach) with an upper instrumented vertebra of C6 or above. Patients with Grade 5, 6, or 7 osteotomies were excluded. Positioning groups were Mayfield skull clamp, bivector traction, and halo ring. Preoperative lower surgical sagittal curve (C2-C7), C2-C7 sagittal vertical axis (cSVA), cervical scoliosis, T1 slope minus cervical lordosis (TS-CL), T1 slope (T1S), chin-brow vertebral angle (CBVA), C2-T3 curve, and C2-T3 SVA was assessed and compared with postoperative radiographs. Segmental changes were analyzed using the Fergusson method.


Eighty patients (58% female) with a mean age of 60.6 ± 10.5 years (range, 31-83) were included. The mean postoperative C2-C7 lordosis was 7.8° ± 14 and C2-C7 SVA was 34.1 mm ± 15. There were overall significant changes in cervical alignment across the entire cohort, with improvements in T1 slope (P < 0.001), C2-C7 (P < 0.001), TS-CL (P < 0.001), and cSVA (P = 0.006). There were no differences postoperatively of any radiographic parameter between positioning groups (P > 0.05). The majority of segmental lordotic correction was achieved at C4-5-6 (mean 6.9° ± 11). Additionally, patients who had bivector traction applied had had significantly more segmental correction at C7-T1-T2 compared with Mayfield and halo traction (4.2° vs. 0.3° vs. -1.7° respectively, P < 0.027).


Postoperative cervical sagittal correction or alignment was not affected by patient position. The majority of segmental correction occurred at C4-5-6 across all positioning methods, while bivector traction had the largest corrective ability at the cervicothoracic junction.Level of Evidence: 4.





Published Version (Please cite this version)


Publication Info

Morse, Kyle W, Renaud Lafage, Peter Passias, Christopher P Ames, Robert Hart, Christopher I Shaffrey, Gregory Mundis, Themistocles Protopsaltis, et al. (2021). A Comparison of Three Different Positioning Techniques on Surgical Corrections and Postoperative Alignment in Cervical Spinal Deformity (CD) Surgery. Spine, 46(9). pp. 567–570. 10.1097/brs.0000000000003851 Retrieved from https://hdl.handle.net/10161/28106.

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Christopher Ignatius Shaffrey

Professor of Orthopaedic Surgery

I have more than 25 years of experience treating patients of all ages with spinal disorders. I have had an interest in the management of spinal disorders since starting my medical education. I performed residencies in both orthopaedic surgery and neurosurgery to gain a comprehensive understanding of the entire range of spinal disorders. My goal has been to find innovative ways to manage the range of spinal conditions, straightforward to complex. I have a focus on managing patients with complex spinal disorders. My patient evaluation and management philosophy is to provide engaged, compassionate care that focuses on providing the simplest and least aggressive treatment option for a particular condition. In many cases, non-operative treatment options exist to improve a patient’s symptoms. I have been actively engaged in clinical research to find the best ways to manage spinal disorders in order to achieve better results with fewer complications.

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