I just joined the forum and saw this message, which is 2 years old. If you or others are still looking for relief from muscle stiffness, pain, and spasms, try using a supplement called "Tonalin CLA," 1000 mg geltabs. It worked for me! (CLA stands for conjugated linoleic acid and Tonalin is the trademark for the type of CLA.) It's usually in the fitness area of the supplement department/store and is supposed to reduce fat and build lean muscle.
I was desperate to find something to relieve the muscle pain and spasms, and thought it might help the muscles relax by "clearing out" the fat. It seems to be very fact-acting--I get relief within a half hour of taking the first one in the morning. It's available in large grocery stores, some discount and warehouse stores, and supplement shops, and is reasonably priced (around $20 for 90 softgels in the Seattle area).
Hope this helps someone else.