Poor posture.
A straightened cervical lordosis is what seems to be commonly referred to as "head forward" posture, which is WRONG for so many reasons: the neck vertebrae loses its natural curve, causing tension in the neck muscles (which actually reach all the way to the side just before the shoulder joint, then tapers down the back to a point between the shoulder blades), which will cause tension in the entire back...you get the drift.
At my follow-up check up after the 6th therapy session, my doctor taught me how to hold my head: he told me to push my chin back. This stopped me from tilting my head up, and also encouraged my neck vertebrae to assume their natural curve. It was SO uncomfortable!! Not to mention almost ugly: my double chin came out!!
AAAARGH!!
But vanity is worthless if it causes self-injury. I finished 6 more sessions of therapy, and at the final check up was discharged. I then told the doctor that I would be going back to my dentist to get braces to fix my jaw alignment because it turns out that my jaw was too far back -- what they call a "deep bite" -- and was continually getting pushed back by a badly-designed bridge. He said that would really help, and that my deep bite was one of the things making me hold my head forward instead of back.
Now I've learned enough to be able to catch myself when I'm slipping back into old habits. It's hard to be accused of getting fat again -- my double chin! -- but I know that as the braces do their work in correcting my jaw structure and I continue working out, eventually even the double chin will disappear. I'll try not to be impatient.
So a summary of the solution -- which is a lot harder than it sounds:
Proper posture: stomach in, chest out, head back. Tip: think of drawing your head back like how a chicken does.
It was uncomfortable like (insert profanity here) when I started doing it myself, but eventually, I began to sense how it was actually relaxing my neck, shoulders and upper back. Now, when I accidentally hold my head forward or tilt my chin up, I'm able to catch and correct myself quickly.
I still have a long way to go. But there's no sense in rushing. I was 43 when the problem was finally diagnosed properly, and corrective therapy was initiated. I'll get there in time. : )