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Related Experiment Video

Updated: Mar 21, 2026

Assessment of Static Graviceptive Perception in the Roll-Plane using the Subjective Visual Vertical Paradigm

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Published on: April 28, 2020

Predicting Cervical Alignment Required to Maintain Horizontal Gaze Based on Global Spinal Alignment.

Bassel G Diebo¹, Vincent Challier², Jensen K Henry³

¹Spine Service, Hospital for Special Surgery, New York, NY.

|May 20, 2016

Summary

This summary is machine-generated.

Cervical alignment depends on thoracolumbar alignment for horizontal gaze. A new formula predicts cervical curve (CC) using lumbar lordosis (LL) and thoracic kyphosis (TK).

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Area of Science:

Spine surgery
Orthopedics
Biomechanical analysis

Background:

Cervical Sagittal Curve (CC) shows high variability and is influenced by thoracic and global spinal alignment.
Previous research has not explored the impact of global spinal alignment on CC for maintaining horizontal gaze.

Purpose of the Study:

To investigate the relationship between cervical alignment and thoracolumbar alignment in maintaining horizontal gaze.
To develop a predictive model for cervical alignment based on global spinal parameters.

Main Methods:

Retrospective cohort study including patients without prior spinal surgery.
Patients stratified by thoracic kyphosis (TK) and sagittal vertical axis (SVA) modifiers.
Stepwise linear regression used to develop and validate a formula for predicting cervical alignment.

Main Results:

Lower cervical curve (C2-C7) was more lordotic with increased SVA across TK groups.
Lumbar lordosis minus thoracic kyphosis (LL-TK) was an independent predictor of CC.
A formula CC = 10 - (LL-TK)/2 predicted actual CC within 8.5° in 64.2% of patients.

Conclusions:

Cervical kyphosis can be normal, but cervical lordosis is necessary with significant SVA and thoracic kyphosis for gaze maintenance.
Cervical alignment is predictable from underlying thoracolumbar parameters (TK and LL).
This predictive capability may aid in surgical planning for spinal deformities.