Chronic Migraine: Diagnosis, Classification, and Evidence-Based Treatment Options

An Evidence-Based, Rehabilitation-Centered Approach

By Juliet Gaisey, MD

Board-Certified Physical Medicine & Rehabilitation Physician

Chronic migraine is one of the most disabling neurologic conditions worldwide. Although migraine is often perceived as simply a severe headache, it is a complex neurobiological disorder involving altered pain processing, trigeminovascular activation, and changes in central nervous system sensitivity.

Many patients with chronic migraine continue to experience disabling symptoms despite trials of medications, emergency department visits, or consultations with multiple specialists. Effective management requires accurate diagnosis, appropriate preventive therapy, and in selected cases, interventional approaches that address contributing cervical and peripheral pain generators.

Understanding Migraine Classification

The International Classification of Headache Disorders (ICHD-3) defines several primary headache disorders relevant to clinical practice.

Migraine Without Aura

Typical features include:

• Headache lasting 4–72 hours

• Unilateral, pulsating quality

• Moderate to severe intensity

• Associated nausea and/or photophobia and phonophobia

Migraine With Aura

Migraine with aura includes transient neurologic symptoms that occur before or during the headache phase. These may include:

• visual disturbances (flashing lights, zigzag lines)

• sensory symptoms such as numbness or tingling

• speech or language difficulty

Chronic Migraine

Chronic migraine is defined as:

• 15 or more headache days per month

• for more than three months

• with at least 8 days meeting migraine criteria

Chronic migraine often evolves from episodic migraine and may be worsened by medication overuse, sleep disturbance, stress, hormonal changes, or cervical musculoskeletal dysfunction.

Headache Disorders That May Overlap with Migraine

Many patients with chronic migraine present with overlapping headache types, including:

• tension-type headache

• cervicogenic headache

• occipital neuralgia

• medication-overuse headache

Accurate differentiation is important because treatment strategies differ.

In clinical practice, migraine frequently coexists with cervical muscle dysfunction and occipital nerve irritation, particularly in individuals with prolonged sitting, postural strain, or prior neck injury.

The Neurobiology of Chronic Migraine

Migraine involves activation of the trigeminovascular system, which leads to release of neuropeptides such as calcitonin gene-related peptide (CGRP). These processes contribute to inflammation and sensitization of pain pathways.

Central sensitization may also develop, resulting in heightened pain responsiveness and symptoms such as allodynia, where normally non-painful stimuli become painful.

Importantly, convergence of trigeminal and upper cervical afferent input within the trigeminocervical complex helps explain why many migraine patients experience neck pain or occipital tenderness.

This neuroanatomical overlap provides a physiologic basis for certain interventional treatments targeting cervical and occipital structures.

Evidence-Based Treatment Framework

Management of chronic migraine typically involves a combination of acute treatment, preventive therapy, and lifestyle interventions.

Acute Migraine Therapies

Acute treatments are used to stop or reduce individual migraine attacks and may include:

• Triptans

• Non-steroidal anti-inflammatory drugs (NSAIDs)

• Gepants

• Ditans

• Antiemetics for associated nausea

These medications are intended for use during migraine attacks rather than daily prevention.

Preventive Pharmacologic Therapy

Preventive treatment is often recommended for patients with frequent or disabling migraine attacks.

Common options include:

• Topiramate

• Beta blockers

• Amitriptyline

• CGRP monoclonal antibodies

• Oral CGRP antagonists (such as atogepant or rimegepant)

• OnabotulinumtoxinA for chronic migraine

Guidance for preventive migraine therapy is outlined by professional organizations including the American Headache Society.

OnabotulinumtoxinA (Botox) for Chronic Migraine

OnabotulinumtoxinA is an FDA-approved treatment for chronic migraine.

Treatment is administered using the PREEMPT protocol, which involves 155–195 units injected across 31–39 standardized sites in the head and neck.

Clinical trials demonstrated that this treatment can significantly reduce the number of headache days per month and improve quality of life in patients with chronic migraine.

Botulinum toxin therapy is specifically indicated for chronic migraine and is not typically used for episodic migraine.

Interventional Approaches in Chronic Migraine

For appropriately selected patients, particularly those with cervical myofascial involvement or occipital nerve tenderness, interventional procedures may play a supportive role.

Trigger Point Injections

Patients with chronic migraine frequently exhibit cervical and upper trapezius myofascial trigger points.

Trigger point injections may help reduce cervical myofascial pain that contributes to headache symptoms in selected patients. These procedures are generally considered adjunctive therapies rather than primary migraine treatment.

Greater Occipital Nerve (GON) Blocks

Greater occipital nerve blocks have been studied in both episodic and chronic migraine.

Research suggests these blocks may reduce headache severity or frequency in some patients when used as part of a broader treatment strategy.⁵

Ultrasound guidance can improve visualization of relevant anatomy and may enhance procedural precision.

Occipital nerve blocks are typically considered adjunctive therapies and do not replace preventive migraine management.

The Role of Rehabilitation Medicine in Migraine Care

Physical Medicine & Rehabilitation (PM&R) offers a function-centered approach to migraine management.

This approach may include:

• identification of cervical biomechanical contributors

• evaluation of posture and muscular imbalance

• coordination with physical therapy

• treatment of myofascial dysfunction

• consideration of interventional procedures when appropriate

For patients whose migraine is associated with neck pain or musculoskeletal dysfunction, a rehabilitation-focused perspective may help address peripheral contributors to headache symptoms.

Chronic Migraine Treatment in Clinton Township and Metro Detroit

Michigan Rehab Consultant PC provides evaluation and multidisciplinary management for patients with chronic migraine and headache disorders throughout:

• Clinton Township

• Macomb County

• Oakland County

• Wayne County

Care focuses on identifying contributing neurologic and musculoskeletal factors and developing individualized treatment plans that support long-term symptom control and functional improvement.

Frequently Asked Questions About Chronic Migraine

What qualifies as chronic migraine?

Chronic migraine is defined as headache occurring on 15 or more days per month for more than three months, with at least eight days meeting migraine diagnostic criteria.

When should preventive migraine treatment be considered?

Preventive therapy is often recommended when migraines occur frequently, cause significant disability, or require repeated use of acute medications.

Can neck problems contribute to migraine?

Many migraine patients experience neck pain or cervical muscle tension. Addressing cervical musculoskeletal factors may help reduce headache triggers in some individuals.

Clinical Takeaway

Chronic migraine is a complex neurologic condition that often requires multimodal treatment. Accurate diagnosis, appropriate preventive therapy, and, in selected cases, targeted interventional procedures may improve outcomes.

In patients with chronic migraine and cervical or occipital involvement, a rehabilitation-centered approach can help address peripheral contributors to headache symptoms while supporting long-term functional improvement.