“Räta på ryggen! (Straighten your back!)” everybody seemed to be telling me during my formative years:
My mother said it, and so did my gym teachers all the way through school, not to speak of my drill sergeant during basic training in the Swedish army. Even my own inner voice in many situations, including standing next to my wife, one inch shorter than I but sometimes wearing two or three inch heels.
I never thought much about it, because I never had back pain, except when I tried to stand straight. I went on three-day hikes with a 40 lb. backpack as a Boy Scout and Explorer and during my brief stint in the army without experiencing more of a backache than anyone else.
More than 25 years into my medical career, I suddenly realized what was going on.
My wife and I were taking private ballroom dance lessons in a dusty upstairs studio with mirrored walls. One time, while our octogenarian instructor was rewinding his cassette tape with foxtrot tunes, my wife looked at my image in the mirror and said:
“Your belt looks crooked.”
It did look crooked, but it wasn’t. I shifted my weight around and made my old, familiar movements to straighten my back. It didn’t feel comfortable at all. Still waiting for the music to start, I shifted my weight from one leg to the other while trying to keep my back straight. With my weight on my left leg and my back straight I felt serious pain in my back and my right leg seemed too long to know what to do with. Shifting my weight to my right leg while lifting my left heel so that only my toes touched the parquet floor, something magical happened.
My back stopped hurting and I felt tall and straight. My belt looked horizontal in the mirror and I looked almost taller than my wife.
My simple leg length difference explained years of poor posture and occasional back pain trying to straighten a back that wasn’t crooked in the first place.
There is a medical lesson here, and as a physician in my early fifties I had heard it and probably preached it many times myself:
Don’t assume the pain originates where it is felt, examine the joints and other structures above and below.
In my case, I don’t even need a heel lift, I just stand square on my right foot and on my left tiptoes and I’m tall and straight. When I walk, I’m only on one foot at a time, so there is no problem then. And these days, I don’t stand still very often.
Physician, heal thyself.
A Country Doctor Writes: 
I enjoyed this. I think that most people have something that’s a bit off. I have one ear slightly higher than the other. It certainly doesn’t bother me, and nobody tells me to straighten my ears, but when I get eye glasses fitted, some people in the optical shop get a bit frustrated.
Another thing about my ears, one sticks out like Dumbo, and one is neatly next to my skull. I must say that often fascinated my students. They generally decided to inform me of this oddity in mid-October.