'proprioceptor' is a noun. It refer to a sensory receptor, found chiefly in muscles, tendons, joints, and the inner ear, that detects the motion or position of the body or a limb by responding to stimuli arising within the organism. 'proprioceptive' is the adjective describing the sensory receptor.

Thank you verrrrrrrrrrrrrrrry much Mohamed, your explanation is so clear, I got it completely! :)))))I was reading an article about touch and somatic sensory, I wonder why they put his case in that article then :O Any way thank you445746784318648 times!

proprioceptive sensations are the sensations that carry info about your muscles and where they are and are they contracted or relaxed, he didn't lose any skin sensation at all, he still can sense touch, fine or crude, temperature and pain. He just doesn't know where his muscles are :) so he can't give the order to move them. Hope you got my point, If you want more info about it just ask. and It's NOT that unusual actually.