Keyboard jockeys pretty much always have tight pec minors. I started watching other people's body mechanics years ago and I had to stop looking at my coworkers because it was distressing. Tight pecs can cause a lot of mid back problems which is how I got diagnosed.

I had this weird muscle spasm a couple inches below my shoulder blade on one side, when holding my arms out in front of me for long. Asked someone about it and they checked my shoulder rotation and told me I needed to work on that.

Test: Stand up and relax your arms at your sides. Get your arms into your most comfortable 'resting' position.

Now look at your hands. In a healthy, balanced adult body your palms are supposed to be facing each other, not pointing straight backward. When I first started working on mine, I was at almost 170 degree angle between my palms. Shoulders nearly totally rolled forward from tight pec minors. After working on it for a while I had it briefly down to around 30 degrees, but I just checked and I'm back up around 80. Back to work I guess...