This is part 2 of my
headache series and today’s discussion is all about Cervicogenic headaches. A
headache that is caused by a dysfunction within the cervical region; this is what
we call as chiropractors, a cervicogenic headache. As you may already know,
most headaches come from a number of sources, Jaw pain, Hypertension,
Dehydration and so on. What I will be
discussing with you today, are some the causes, diagnoses, and treatments of a
cervicogenic headache.
Cervicogenic headache
usually starts in what we call the suboccipital area, which is that muscular
area that is just under the occiput of the head. That pain starts there - it
can be on one or both sides - and it tends to radiate up into the head and
around the head. The easiest way to visualize it is to actually take the palm
of your hand and place it on the back of the head and that really is where the
pain spreads. More rarely, the pain can travel to the front of the head and
behind the eye. Once again, that's not common and it is even less common for it
to just appear in the front of the head or behind the eye, but it does happen.
What
causes a Cervicogenic Headache?
In order to discuss the
causes of cervicogenic headache, I need to take a step back for a second and
talk about the anatomy cervical spine “neck”. What we're looking at here is the back of the
head, the neck or cervical spine, and specifically what we're looking at is
these little joints. Now these are facet
joints - or
zygapophysial joints – the hinge-like joints in the spine. Now, these joints
are true joints - in other words, they have the synovial fluid, synovial
capsule, cartilage - and they can react like any other joint; in other words,
they can get irritated, inflamed, and can become painful. Now, what's important
in this context is that the innervations for these joints comes from a very
small branch - called medial branch - that comes around here and goes into the
joint. At times, that branch continues on and becomes another nerve. The nerve
we're concerned about specifically is called the third occipital nerve. This
nerve crosses the C2-3 facet joints and the facet joints are named for the
different vertebral
bodies that
are interfacing and forming that joint, so this is a C2 and C3. So a C2-3 is
crossed by the third occipital nerve, then continues onto the occiput and
around the scalp. If there is irritation at this joint, this nerve tends to
transmit pain and cause the pain that we're discussing - the pain that actually
encompasses the occiput and the back of the head.
Now, the causes of this,
there are many to discuss. If we are to group them together, the most common
cause is really similar to a whiplash injury.
If you think about the joint itself as a hinge-like joint that provides the
sliding motion. Whiplash is essentially an acceleration-deceleration injury
grinding that joint. That usually is the first step to precipitating this
cervicogenic headache because it irritates the joint, then the irritation
drives the whole process.
Now, whiplash or
acceleration-deceleration injury through that joint can mean motor vehicle
accidents, can mean just falls - commonly falls on ice - that cause this motion
of the head and that's usually more common in the younger population. When we
talk about the older population and when arthritis becomes more of a problem,
that arthritis in that same joint can also cause irritation, inflammation, and
irritation to that nerve, causing that cervicogenic headaches. Of course,
anything that would cause irritation to that nerve would cause the headaches
and muscle spasms,
grinding that joints, irritation to the joint from other causes, from the
laxity of the joint, in different conditions that really predispose the
hypermobility or increased mobility of that joint can also predispose to
inflammation and irritation of that nerve, once again predisposing one to
cervicogenic headaches.
How
is a Cervicogenic Headache Diagnosed?
Diagnosing cervicogenic
headache can be somewhat tricky because the headaches resemble a number of
different headaches and to complicate the matter, they can trigger other
headaches. So, for instance, patients can have cervicogenic headaches as
another trigger for a migraine. Cervicogenic headache in itself can cause
tension types of headache. But if there is suspicion for cervicogenic headache,
the studies have shown that a very precise diagnostic procedure can be very
accurate in diagnosing it.
The way this procedure is
done is under controlled conditions and the guidance of an x-ray or fluoroscopy. A needle is
actually placed at the joint at three separate spots - at the most likely
places of this nerve - and anesthetic is placed very precisely at the location
of the nerve. If this eliminates the pain, then that's a very positive
indication that that's the source of the pain.
How
is a Cervicogenic Headache Treated?
In discussing treatments for
cervicogenic headaches, it's important to remember that we have to look at it
as constellation of symptoms, even though we know that there is a third
occipital nerve that gets irritated and that's what we have to treat, that
resolves a part of the problem - a very important part of the problem - but
from literature we know that we see the best outcomes by approaching it from
several different directions. What I mean by that is: one of the main
treatments for cervicogenic headaches is addressing the pain generator. So,
reducing the inflammation at the joint and reducing the inflammation at that
third occipital nerve is one of the first things to do. That can be done by
placing medication right at the source of the inflammation and irritation.
Another way to do this - and this is a very well-studied approach - is to use radiofrequency rhizotomy.
Radiofrequency rhizotomy essentially eliminates those feeding nerve fibers and
the way this is approached is a probe is placed along the path of this nerve
and then radiofrequency energy is used in order to treat this area to eliminate
those nerve fibers.
Besides using these
techniques, what's important to remember is that chiropractic
care and theruapeutic modalities such as Ice and Interferntial units to
decrease inflammation and reduce pain, along with PNF stretching,
or proprioceptive neuromuscular facilitation stretching,
is a set of stretching techniques
commonly used in clinical environments to enhance both active and passive range
of motion in order to improve motor performance and aid rehabilitation. So,
it is important to address this from a point of controlling the pain because,
as we know, pain really drives a lot of the muscle spasms and prevents one from
doing the exercises and manipulations that are necessary in order to get
better. Once everything comes together and all of the components of the biomechanical
chain are treated, the myofascial component is treated, the irritation and
inflammation is eliminated, most patients tend to recover very well.