In 1980 Alberca et al. described a patient with a syndrome of increased muscle irritability, who presented ondulating muscle rolling movements and electrically silent cramps, myoedema and muscle reactions to mechanical stimulation similar to myotonic response, suggesting a disfunction at myofibrillar level.
For c-3po, it was a costume, Anthony Daniels played c-3po: For R2-D2, It was a costume and a remote controlled robot. CGI was also used in the prequel trilogy. So, they had Kenny Baker to play him : And from Portrayal section of wookieepedia article on R2-D2 :
Sean Penn met with El Chapo while he was on the run in Mexico last year and the actor is now under investigation; Jungle meeting organized by Penn, Mexican actress Kate del Castillo and a fixer, with permission of Sinaloa cartel; Penn did not turn El Chapo in as he did not want to 'f***' with his trust'. The drug lord was recaptured in raid Friday