Occupational Therapists are trained in upper body anatomy and kinesiology, and furthermore are trained in task analysis. I recommend a consultation with an Occupational Therapist, particularly one who is also a Certified Hand Therapist. The OT can design a home exercise program for you and can make recommendations about either changing your environment (changing the seat height, therefore different ergonomics?) and/or changing your body mechanics. A doctor's referral is necessary for an OT visit. Occupational Therapy has its roots in crafts, so an OT will have a deep appreciation for what you do.