When the MRI shows a bulging or herniated disc, what percent of the time is this false positive result?
In an article by Jensen (Jensen MC, Brant-Zawadzki MN, Obuchowski N, Modic MT, Malkasian D, Ross JS, Magnetic resonance imaging of the lumbar spine in people without back pain., N Engl J Med. Jul 14;331(2):69-73..1994) his group reported that in a sample of 91 patients, WITHOUT any back pain, 27 of these patients have a bulging or herniated disc on MRI images. Therefore, 30% of the time (27/91) the MRI shows a disc abnormality, but the patient does not have any symptoms. Therefore, for discs in the lower back, the MRI has a false positive rate of 30%. #2- Question: Can EMG/nerve conduction studies tell if a patient has pain. Answer: Not very well. Electromyographic studies and nerve conduction studies primarily measure motor fiber conduction speed and the integrity of the muscle fibers. Peripheral nerves are really a collection of both sensory and motor nerves. Various nerve roots coming off the spinal cord mix in the plexus (brachial or lumbar plexus) and go to the arms and legs as mi
