I have a desk job and I notice quite a bit of stiffness around the upper spine. I remember hearing in an episode of Barbell Shrugged that the number one reason people end up in nursing homes is loss of thoracic spine mobility (because they can no longer clean up after using the restroom). Of course I'd like to avoid that, but I'd also like to increase the mobility and strength in that area, and hopefully combat the stiffness.
For mobility, I do upper-spine foam rolling for stretching, and also some spinal rotation stretches, but I imagine having stronger surrounding musculature would improve the situation. For strength training, I do deadlifts occasionally, and squats and cleans frequently, but I'm not sure if there's something else I could add to my routine to improve on the thoracic area of the spine. Any recommendations?