Cervical spine alignment, sagittal deformity, and clinical implications: a review

Area of Science:

• Orthopedics and Spine Surgery
• Radiology and Imaging
• Biomedical Engineering

Background:

• Cervical alignment significantly influences spinal health and patient outcomes.
• Quantifying cervical alignment is essential for diagnosing and managing spinal conditions.
• Cervical deformity can affect global sagittal alignment and patient-reported outcomes.

Purpose of the Study:

• To review normal cervical alignment and methods for its quantification.
• To explore the association between cervical alignment and deformity, myelopathy, and adjacent segment disease (ASD).
• To discuss the relationship between cervical sagittal alignment and health-related quality of life (HRQOL).

Main Methods:

• Narrative review of existing literature on cervical alignment.
• Discussion of popular methods for quantifying cervical alignment (e.g., cervical lordosis, sagittal vertical axis, chin-brow to vertical angle).
• Analysis of studies correlating radiographic parameters with HRQOL and ASD.

Main Results:

• Cervical deformity impacts global sagittal alignment and can lead to ASD.
• Sagittal malalignment may promote ASD, particularly postoperatively.
• Cervical kyphosis can cause spinal cord compression and tension, contributing to cervical myelopathy.

Conclusions:

• Comprehensive assessment of global cervical-pelvic relationships is vital for understanding cervical deformities.
• Cervical sagittal alignment plays a substantial role in cervical myelopathy and ASD development.
• Further studies are needed to validate parameters correlating cervical alignment with HRQOL outcomes.