I have covered a number of subjects in my blog related to traumatic brain injury (TBI) and ocular function. As a person might suspect, head injuries are frequently connected to neck injuries. In fact, neck injuries from motor vehicle accidents are more common than concussions.
If one considers a whiplash injury, the brain can go through a significant acceleration/deceleration phase inside the skull, but the neck is almost always snapped backward and forward. There is nothing to protect the neck and cervical spine.
Injuries to the neck and cervical spine are usually referred to chiropractors and orthopedic/spine specialists if there are abnormal findings on an MRI scan. How are the neck and eyes connected?
Each time your head turns, your neck rotates, but your eyes also move often in the opposite direction to maintain the visual image on the retina. This is part of the vestibular apparatus which coordinates balance of head and eye movements. This can be disrupted in TBI and cause double vision and sometimes nystagmus (abnormal fluttering eye movements). Both of these subjects have been covered in previous blogs.
If just the neck is in pain, this alone can effect vision. Just try holding your neck still and looking around the room. It becomes very awkward because it’s much easier for your brain to move your neck than turn your eyes. When we look around our world, the head and neck move as a unit and the eyes automatically rebalance with small movements.
If a person’s neck is stiff or in pain, that person will want to move his/her neck less to avoid discomfort. In this case, the eyes need to move from side to side more frequently to cover for the lost neck function or the person would need to turn the entire body.
The eyes don’t like this extra exercise and frequently become fatigued. A common complaint of neck injury becomes visual fatigue, eye strain, and headaches even if there is no TBI. Now as previously discussed, these symptoms can overlap with those of TBI. An experienced ophthalmologist used to evaluating head and neck trauma can often be helpful in making this distinction- it may have implications on treatment.
Chiropractors and eye doctors usually don’t work together, but I frequently get referrals from chiropractic doctors because their patients frequently have visual complaints. Neck strain and pain is treated by chiropractors after automobile accidents. I have just described one simple mechanism by which neck immobility can effect eye movement and cause visual symptoms. It’s often hard to tell if it’s just the neck or more is going on in the brain and eyes. I encourage my chiropractic colleagues to ask patients about eye stain and visual fatigue. These patients deserve an eye evaluation to make sure nothing else is going on with the eyes or brain. A one time consultation is usually all that is necessary.