Cervical Sagittal Alignment: Literature Review and Future Directions

Area of Science:

• Orthopedics
• Neurosurgery
• Spine Surgery

Background:

• Cervical alignment has gained prominence in spine deformity research.
• Studies have evolved from normative data to exploring its correlation with global balance, prognosis, and surgical outcomes.
• Despite progress, defining normal cervical sagittal alignment and deformity remains challenging.

Purpose of the Study:

• To summarize existing literature on cervical sagittal alignment.
• To discuss key findings and identify gaps in current research.
• To outline future research directions using a '5W1H' framework.

Main Methods:

• Literature review of cervical sagittal alignment studies.
• Analysis of research trends and definitions.
• Application of the '5W1H' (Who, Why, What, How, When, Where) framework to guide future research.

Main Results:

• Current research lacks a definitive understanding of normal cervical sagittal alignment and deformity.
• Cervical alignment is often viewed as an extension of thoracolumbar deformity, neglecting unique cervical biomechanics.
• The role of musculature connecting the cranium-cervical-thoracic spine and upper extremities in cervical alignment is underappreciated.

Conclusions:

• Further research is needed to establish clear definitions and understanding of cervical sagittal alignment and deformity.
• Future studies should incorporate the unique biomechanical features of the cervical spine.
• A comprehensive '5W1H' approach will guide future research to address current knowledge gaps.