Stiff ##ness Syndrome is a rare disorder that causes painful muscle weakness and stiffness . Although SPS is a neurological disorder , it has `` features '' of an autoimmune disease , according to the National Institutes of Health . An estimated one in every 1 million people has SPS . Stem cell transplantation can successfully treat this debilitating disease .
Stiff ##ness Syndrome is a rare disorder that causes painful muscle weakness and stiffness . An estimated one in every 1 million people has SPS . Stem cell transplantation can successfully treat this debilitating disease .