There is not just one pterygoid muscle... actually there are internal, external, lateral and medial pterigoids, that are involved in the movement of the mandible. The reason that these muscles come up so often in relationship to the issue that we are all interested in so much is that they are affected when surgery is part of the treatment protocol, and they actualy come into contact with and protect the maxillary arteries. They are frequently tissues that invasive carcinomas can affect. More knowlege than this about their locations and functions serves doctors that are working on us but does not help us. By the way, the "big honkin muscle" that stand out on the side of your neck is the sternocleiodmastoid and runs to your sternum from the upper part of your neck behind your ear, so that you can rotate your head......