Besides an emg what other tests can be done to determine what nerve or nerves are being compressed in the elbow my x rays just showed arthritis of the?

Nerve compression. X-rays show bony structures; could show bone spurs that might press on nerves. Emg tests nerve function. Mri might show actual compression of nerve at elbow. Physical exam can also help determine if u have ulnar nerve entrapment. Trust doc.
Ncv. It is usually paired with the emg. It is a nerve conduction velocity test. A good clinical exam carries much weight as well.
NCS. Nerve conduction studies are often done with EMG to get a better idea of whether or not nerves are involved. Here's a link to information on nerve conduction studies: http://abcnews.Go.Com/health/diagnosingpain/story?Id=4040291#.Ulffqyf7kag.