Quantifying the Importance of Upper Cervical Extension Reserve in Adult Cervical Deformity Surgery and Its Impact on Baseline Presentation and Outcomes.

Abstract

BACKGROUND AND OBJECTIVES: The concept of upper cervical (C0-C2) extension reserve (ER) capacity, ER relaxation, and their impact on outcomes following surgical correction of adult cervical deformity (ACD) has not been extensively studied. We aimed to evaluate the impact of upper cervical ER on postoperative disability and outcomes. METHODS: Patients with ACD, from a retrospective cohort study of a prospectively collected multicenter database, undergoing subaxial cervical fusion with 2-year (2Y) follow-up data were included. ER was defined as: ΔC0-C2 sagittal Cobb angle between neutral and extension. Relaxation of ER was defined as the ER mean in those that met all ideal thresholds in radiographic parameters for Passias et al CD modifiers. We used multivariable logistic regression to adjust for confounding, with conditional inference tree approaches used to determine thresholds that affect postoperative ER resolution on patient-reported outcomes. RESULTS: A total of 108 patients with ACD met inclusion. Preoperative C0-C2 ER was 8.7° ± 9.0°, and at last follow-up was 10.3° ± 11.1°. Preoperatively 29% of the cohort had adequate ER, whereas 60% had improved ER postoperatively, with 50% achieving adequate ER by 2Y. Lower ER correlated with greater CD (P < .05). Preoperatively, greater ER had lower Neck Disability Index (P < .001). Controlled analysis found improved ER to have a greater likelihood of achieving Neck Disability Index minimum clinically important difference (odds ratio 6.94, [1.378-34.961], P = .019). In those with inadequate ER at baseline, the preoperative C2-C7 of < -18° and T1 slope-cervical Lordosis mismatch of >59° for T1 slope-cervical Lordosis mismatch was predictive of ER resolution. In those with preoperative C2-C7 >-18°, a T1PA of >13° was predictive of postoperative return of ER (all P < .05). Surgical correction of C2-C7 by > 16° from baseline was found to be predictive of ER return. CONCLUSION: Increased preoperative use of the C0-C2 ER in CD was associated with worse baseline regional and global alignment and adversely affected health-related measures. Most of the patients had ER relaxation postoperatively. In those who didn't, however, there was a decreased likelihood of achieving satisfactory outcomes.

Department

Description

Provenance

Subjects

ACD, Adult cervical deformity, Complications, High-risk, Optimization, Outcomes, Upper cervical extension reserve

Citation

Published Version (Please cite this version)

10.1227/neu.0000000000003538

Publication Info

Passias, Peter G, Jamshaid M Mir, Andrew J Schoenfeld, Anthony Yung, Justin S Smith, Virginie Lafage, Renaud Lafage, Bassel Diebo, et al. (2025). Quantifying the Importance of Upper Cervical Extension Reserve in Adult Cervical Deformity Surgery and Its Impact on Baseline Presentation and Outcomes. Neurosurgery. 10.1227/neu.0000000000003538 Retrieved from https://hdl.handle.net/10161/32491.

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Scholars@Duke

Passias

Peter Passias

Instructor in the Department of Orthopaedic Surgery

Throughout my medical career, I have remained dedicated to improving my patients' quality of life. As a specialist in adult cervical and spinal deformity surgery, I understand the significant impact our interventions have on individuals suffering from debilitating pain and physical and mental health challenges. Spinal deformity surgery merges the complexities of spinal biomechanics with the needs of an aging population. My research focuses on spinal alignment, biomechanics, innovative surgical techniques, and health economics to ensure value-based care that enhances patient outcomes.

Shaffrey

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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