Migraine, a pain in the neck, literally

Migraine and neck pain have significant overlap, as they share many neural pathways. Hence, migraine can result in neck pain, and migraine can also be predominantly provoked by neck pain. Differentiating these two entities is important as therapeutic strategies can be a bit different.

Migraine and neck pain

Migraine is not merely a headache, but rather a a state of brain dysfunction, resulting in heightened sensitivity to nerve input. When you look at migraine like this, it becomes easier to explain some migraine symptoms; the nausea and smell sensitivity, the light sensitivity, the noise sensitivity and the heightened pain feelings (and hence the headache).

Unfortunately, this heightened sensitivity occurs at the brainstem level, where many sensory nerves meet; one of the major nerves is the trigeminal nerve, which is the one innervating the face and forehead.

However, the nerves that innervate the upper neck and back of head also land here, and they also become more sensitive in migraine. These nerves are named the "occipital nerves", and there are three of them on each side; greater, lesser and third. They convey pain and touch sensations from upper neck and back of head, and they converge in the upper neck where they enter at the levels of upper cervical spine C2 and C3.

The command center of the trigeminal nerve (aka the nucleus where the nerve starts from) is a long one, and it makes very tight connection with the neurons that form these C2 and C3 nerves. Hence, when the trigeminal nerve becomes sensitized due to the migraine attack, these nerves become sensitized as well. Sensitization means they become easier to provoke, and more capable of augmenting any signal they get.

Once this process kicks in, patients start experiencing pain in their neck on top of their migraines, which at times can be more distracting that the migraine pain itself.

Cervicogenic headache, and migraine:

Here is where things get complicated; neck pain not only can be the result of migraine, but it also can be the cause of it (or the cause of it provocation to be accurate).

First, let's clear the terminology; cervicogenic headache basically means a headache originating from the neck. Neck pain (and pain in the spine in general) is frequently due to joint inflammation (i.e. arthritis). This is more common in the mobile segments of the spine such as the lower back (the lumbar spine), or the lower neck, while it is not as common in upper neck and thoracic area.

However, certain factors can predispose the upper neck joints to have arthritic changes, such as whiplash injuries, or non-ergonomic forward neck posture, like what is seen with long office work in front of screens.

When the cervical spine joints at C2/C3 become involved, it is quite common for the adjacent occipital nerves to become irritated, mainly because of their proximity and also because of the muscle tug on them as muscles become stiffer around these joints.

Once these irritated nerves send the signal to the trigeminal nerve via the connections we talked about above, patients start experiencing headache. Now the critical part is whether this headache will become a migraine or not, and this mainly has to do with the patient's own threshold for a migraine. The lower their threshold is for migraine (i.e. the easier it is to provoke a migraine), the more likely this headache will end up looking just like a migraine. In our experience, people with history of migraine headaches will usually have a significant deterioration of their migraines with any neck injury or arthritic changes.