Not withstanding all of the other constructive input, your husband may be suffering from muscular back pain. Most of us in treatment find ourselves fatigued and lacking physical activity. As such, the upper back muscles, which are intricately intertwined can cause severe pain at the point of a muscle knot or beyond as referred pain. I'm 6 weeks post esophagectomy and have been experiencing significant pain in my scapular shelf with referred in my latimus dorsi. I'm also a personal trainer and am now engaging in my own physical therapy to strengthen and stretch these muscles. I'm making good progress so far. If your husband hasn't done physical therapy, I highly recommend it. It's sometimes amazing the relief a good therapist can bring. Best of luck to you.