Suggest Treatment For Weakened Left Arm

General weakness in left arm, and both hands, which are also some what cold. I had pain in my left shoulder for about a year, but cortisone injections, and laser treatments did virtually nothing to ease the pain. An orthopedic surgeon, did an MRI and described the shoulder as grossly inflamed. Surgery was suggested as an ultimate possibility, at which point I stopped going to see him. In subsequent years the pain has virtually disappeared in my left arm, but it has grown weaker and weaker, along with both hands. Any ideas. PS. I do have a family doctor, but I really hate to visit if it s something trivial.