Spinal stenosis, defined by the narrowing of spaces within the spine, can cause severe headaches, though it rarely causes a true migraine. While a migraine is a specific neurological disorder, the structural changes from spinal stenosis can trigger a different, often debilitating, type of headache. Understanding the difference between these headache types and the underlying spinal mechanics is the first step toward effective relief.
Understanding Cervical Spinal Stenosis and Associated Symptoms
Spinal stenosis can develop anywhere, but only narrowing in the neck, known as cervical spinal stenosis, can cause symptoms affecting the head. This narrowing often results from age-related changes, such as thickening ligaments, bone spurs (osteophytes), or bulging intervertebral discs. These changes reduce the space available for the spinal cord and branching nerve roots.
Pressure in the cervical spine causes pain and stiffness. Compression of nerve roots can also cause radiculopathy, characterized by pain, weakness, numbness, or tingling traveling into the shoulder and arm. This nerve irritation in the upper spine allows pain to be referred or felt in the head, even though the structural problem is in the neck.
The Critical Distinction: Migraine Versus Cervicogenic Headache
Spinal stenosis rarely causes true migraines, but it frequently causes a condition known as a cervicogenic headache (CGH). True migraines are a primary headache disorder, originating from complex neurological and vascular processes within the brain. They typically present with throbbing or pulsating pain that is often bilateral, affecting both sides of the head. Migraines are frequently accompanied by neurological symptoms, such as aura, sensitivity to light (photophobia) and sound (phonophobia), and nausea or vomiting.
In contrast, CGH is a secondary headache resulting directly from an underlying disorder in the cervical spine. The pain is usually non-throbbing, described as a dull ache or pressure starting in the neck or back of the head. The pain is typically unilateral, remaining on the same side as the spinal issue. CGH is often triggered or worsened by specific neck movements, sustained awkward postures, or pressure applied to certain neck points. Cervical spinal stenosis is a common cause of CGH because the structural compression creates irritation in the upper spinal segments.
Mechanisms Linking the Cervical Spine to Head Pain
The pathway explaining how neck pain is perceived as head pain involves the trigeminocervical nucleus (TCN) in the brainstem. The TCN is a major relay center where sensory information from two separate nerve systems converges. The trigeminal nerve system carries sensation from the face and front of the head, while the upper cervical spinal nerves transmit sensory input from the back of the head and neck structures.
When cervical stenosis causes irritation or inflammation in the upper cervical nerves, pain signals are sent to the TCN. Because trigeminal nerve fibers also terminate in the same area, the brain misinterprets the signal originating from the neck as pain coming from the trigeminal nerve’s distribution, such as the forehead, temples, or behind the eye. This phenomenon is known as referred pain. Constant irritation from spinal compression also leads to protective muscle spasms in the neck and shoulders, further contributing to the referred head pain.
Addressing the Underlying Spinal Cause
Treatment for headaches caused by cervical stenosis focuses on reducing neck compression and inflammation. Conservative approaches are the first line of defense to alleviate cervicogenic pain. Physical therapy is often recommended to improve neck mobility, strengthen supporting muscles, and correct poor posture.
Anti-inflammatory medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), help manage pain and reduce inflammation around affected nerve roots. For localized and severe pain, epidural steroid injections may deliver anti-inflammatory medication directly to the compressed area. If conservative methods fail and symptoms are severe or progressive, surgical decompression may be necessary. Procedures like laminectomy or foraminotomy remove the source of compression, such as bone spurs or thickened ligaments, to create more space for the nerves and spinal cord.