Illustration of a glowing human neck with the cervical spine visible, emphasizing the C1 vertebra.

Is Your Neck Normal? Unveiling the Truth About C1 Stenosis and Your Spine

Reese Marlowe in Health & Wellness November 2025 • 4 min read.

"Discover the surprisingly common variations in your upper cervical spine and what they mean for your health. Are you at risk?"

Have you ever wondered if that nagging neck pain or stiffness could be something more? The cervical spine, particularly the C1 vertebra (also known as the atlas), is a critical area often overlooked. Understanding its anatomy and potential issues like C1 stenosis is key to maintaining overall spinal health.

C1 stenosis refers to the narrowing of the spinal canal at the level of the atlas vertebra. This narrowing can put pressure on the spinal cord, potentially leading to various neurological symptoms. While some individuals may experience noticeable pain or discomfort, others might be completely unaware of the condition.

A recent study published in the European Journal of Orthopaedic Surgery & Traumatology sheds light on the variations in the C1 spinolaminar line and the prevalence of C1 stenosis in a normal population. This research helps us understand how common these variations are and what factors might contribute to the development of stenosis.

What Exactly is the C1 Spinolaminar Line and Why Does It Matter?

Illustration of a glowing human neck with the cervical spine visible, emphasizing the C1 vertebra.

The C1 spinolaminar line is an anatomical reference point used in radiology to assess the alignment and space within the upper cervical spine. Imagine drawing a line from the C3 vertebra through C2 to the C1 lamina. The position of the C1 lamina relative to this line is crucial.

Researchers use the relationship between the C1 lamina and the C3-C2 spinolaminar line to check for possible stenosis. This line helps determine if there is enough space for the spinal cord at the C1 level. The study categorizes this relationship into three types:

Positive: The C1 lamina sits ventral (in front of) the C3-C2 line by 2mm. This suggests potential narrowing.
Neutral: The C1 lamina aligns within 2mm of the C3-C2 line. This is considered normal alignment.
Negative: The C1 lamina lies dorsal (behind) the C3-C2 line by 2mm, indicating more space than a positive alignment.

The study highlights that even in individuals without any symptoms, there can be variations in the C1 spinolaminar line. The study of 315 volunteers revealed that 4.4% had a positive C1 spinolaminar line, 58.4% had a neutral alignment, and 37.1% had a negative alignment. This underscores that some degree of variation is normal, but a 'positive' alignment warrants further attention.

Taking Control of Your Cervical Spine Health

While the study indicates that variations in the C1 spinolaminar line are relatively common, it also emphasizes the importance of awareness. If you're experiencing persistent neck pain, stiffness, or neurological symptoms, it's essential to consult a healthcare professional. Early diagnosis and management can help prevent potential complications and ensure a healthy, pain-free future.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1007/s00590-018-2159-1, Alternate LINK

Title: Variation Of C1 Spinolaminar Line And Prevalence Of C1 Stenosis In Normal Population

Subject: Orthopedics and Sports Medicine

Journal: European Journal of Orthopaedic Surgery & Traumatology

Publisher: Springer Science and Business Media LLC

Authors: Sombat Kunakornsawat, Letho, Tinnakorn Pluemvitayaporn, Pritsanai Pruttikul, Chaiwat Piyasakulkaew, Kanthika Wasinpongwanich, Piyabuth Kittithamvongs

Published: 2018-03-03

Everything You Need To Know

What is C1 stenosis and how does it affect the body?

C1 stenosis is the narrowing of the spinal canal at the level of the C1 vertebra, also known as the atlas. This narrowing can put pressure on the spinal cord, potentially leading to various neurological symptoms. While some individuals may experience noticeable pain or discomfort, others might be completely unaware of the condition. This highlights the importance of understanding the potential issues in the upper cervical spine for overall spinal health. Further, if stenosis is suspected based on the C1 spinolaminar line, more advanced imaging such as MRI may be helpful to evaluate for spinal cord compression. Other causes of spinal cord compression such as disc herniations, ligament thickening, and bony overgrowth may be considered with advanced imaging.

What is the C1 spinolaminar line, and how is it used to assess potential problems in the cervical spine?

The C1 spinolaminar line is an anatomical reference point used in radiology to assess the alignment and space within the upper cervical spine. Researchers use the relationship between the C1 lamina and the C3-C2 spinolaminar line to check for possible stenosis. The position of the C1 lamina relative to the C3-C2 line helps determine if there is enough space for the spinal cord at the C1 level. The study categorizes this relationship into three types: Positive: The C1 lamina sits ventral to the C3-C2 line; Neutral: The C1 lamina aligns within 2mm of the C3-C2 line; Negative: The C1 lamina lies dorsal to the C3-C2 line.

The C1 spinolaminar line study showed 4.4% of people had a positive C1 spinolaminar line. What does that mean for me if I have neck pain?

The study of 315 volunteers revealed that 4.4% had a positive C1 spinolaminar line, 58.4% had a neutral alignment, and 37.1% had a negative alignment. A positive alignment warrants further attention. If you're experiencing persistent neck pain, stiffness, or neurological symptoms, it's essential to consult a healthcare professional. Early diagnosis and management can help prevent potential complications and ensure a healthy, pain-free future. A positive C1 spinolaminar line suggests potential narrowing at the C1 vertebra. However, the study does not address whether those with a positive C1 spinolaminar line had neck pain. There may be an incidental finding of a positive C1 spinolaminar line and other causes of neck pain may be present.

What are the different categories of C1 lamina alignment relative to the C3-C2 spinolaminar line, and what do they indicate?

The relationship between the C1 lamina and the C3-C2 spinolaminar line is categorized into three types: Positive, Neutral, and Negative. A 'Positive' alignment means the C1 lamina sits ventral (in front of) the C3-C2 line, suggesting potential narrowing. A 'Neutral' alignment indicates the C1 lamina aligns within 2mm of the C3-C2 line, considered normal alignment. A 'Negative' alignment means the C1 lamina lies dorsal (behind) the C3-C2 line, indicating more space than a positive alignment.

If variations in the C1 spinolaminar line are relatively common, should I be concerned about my cervical spine health?

The study indicates that variations in the C1 spinolaminar line are relatively common. It also emphasizes the importance of awareness. If you're experiencing persistent neck pain, stiffness, or neurological symptoms, it's essential to consult a healthcare professional. Early diagnosis and management can help prevent potential complications and ensure a healthy, pain-free future. The study does not describe the next steps in diagnosis if a patient has a positive C1 spinolaminar line. These next steps might include advanced imaging with MRI and consultation with spine specialists.