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 :
Shippo is the first character to join Inuyasha and Kagome in the quest to defeat Naraku and purify the Shikon no Toma. He is an adolescent fox demon or kitsune youkai as he is refereed to in the Japanese version of the anime. Although Shippo's age is never mentioned he appears approximately five years old.