In humans and other tailless primates ( e.g . great apes ) since Nakalipithecus ( a Miocene hominoid ) Masato ( 2004 ) , Acquisition of bipedalism , the coccyx is the remnant of a vestigial tail , but still not entirely useless .
The coccyx is an important attachment for various muscles , tendons and ligaments which makes it necessary for physicians and patients to pay special attention to these attachments when considering surgical removal of the coccyx .
Coccyx