Do you ever wonder what neurologists are really doing to you during your physical exams and what they are looking for?
In general, the neurologic exam concentrates on several specific areas: mental status, cranial nerves, motor function, sensation and reflexes.
Depending on whether it is your first visit or a routine follow-up visit, the exam's length and complexity may vary. It actually begins before you realize it!! The neurologist checks the forms you filled out to see if the handwriting is small or shaky, then closely observes you during the initial interview - is there a lack of facial expression, a lack of movement of one arm or leg, a tremor and is the voice loud or indistinct? Often the diagnosis of Parkinson's disease is reached within the first minute or two the neurologist is in the room.
Then the neurologic examination begins. Although the exams performed by different neurologists vary widely, and also from one visit to the next, there are certain things a neurologist checks to determine the diagnosis (is it Parkinson's disease?) or to see how well you are responding to medication.
Mental Status: During the interview, and often with additional questioning, us¬ing standardized tests of cognitive function, the neurologist assesses your memory, concentration skills, language skills and orientation.
Gait: Usually you are asked to walk back and forth, on your toes and heels, then in a straight line. Observing whether you swing your arms normally or not may provide an early tip-off to the diagnosis of Parkinson's disease. You may be pushed or pulled to see how well you can maintain your balance (postural stability). You also watched to see if you have trouble rising from a chair and whether you stand straight or stooped.
Cranial Nerves: The cranial nerves are those that supply the eyes, face, ears, mouth/tongue and neck. A lack of facial expression (masked facies) may be noted, but there can be certain abnormalities that indicate a diagnosis of something other than typical Parkinson's disease (an inability to normally move the eyes, for example).
Motor Function: During this portion of the examination, your doctor checks your strength, pulling or pushing your arms and legs, comparing one side of the body to the other, and seeing if there is a difference between the upper and lower limbs. Your doctor will also move your arms and legs while you relax, to decide if there is increased tone or stiffness. (In Parkinson's disease we are looking for "cogwheeling," which is a type of stiffness with a "ratchety" feeling.) The speed of your movements is also examined: you are often asked to hold your arms in front of you and rapidly move them from "palm up" to "palm down," something called "rapid alternating movements." Additional maneuvers may be performed, such as finger tapping and repetitive "hand opening-closing," looking for bradykinesia (slowness of movement). The speed of these rapid movements often helps in making the diagnosis. It is important to note whether the abnormalities are worse on one side or the other.
The search for tremor actually continues throughout the entire time with your doctor. A tremor observed while a person is sitting quietly is known as a resting trem¬or and is the most typical type seen in PD. Often, this tremor is visible while you are walking, and is also called a "pill-rolling" tremor, named after the movement that an old-time pharmacist would make as he created a pill between his fingers. Tremor can also be seen with certain activities (holding objects, writing, etc.), and may or may not be seen in PD. Often you are asked to hold your arms outstretched, or to touch your finger to your nose.
Sensation: The sensory exam consists of being poked with a pin, lightly brushed with cotton/tissue, or asked whether you feel a vibrating tuning fork, or if a finger or toe is moved upward or downward. Again, the physician wants to know whether you feel these sensations equally on both sides of the body and whether it differs between how it feels in your feet/hands (distal sensation) or closer portions of the limbs (proximal sensation). This portion of the exam is probably the least important in the diagnosis of PD. However, certain abnormalities might be clues to a different neurologic disorder.
Reflexes: Here the doctor observes how your limbs react to being tapped with a reflex hammer (deep tendon reflexes). In particular, are the responses equal on both sides and are they increased or decreased in a particular pattern? Another very important reflex commonly tested is the plantar reflex, when the bottom of your foot is stroked unpleasantly to see what direction your toes move. This is one of the most important tests in neurology. If the toes move upward in a specific way, it is known as a "Babinski sign." This is not usually seen with PD, but may indicate another disorder.
The neurologic examination remains the most accurate way to diagnose Parkinson's disease, coupled with the history that you give. Testing is generally not required to make a diagnosis, but is occasionally ordered to rule out a different diagnosis, if there are unusual features noted during the exam. Remember: the length of the neurologoc exam may vary from visit to visit, with the initial consultation generally being the most extensive examination, and follow-up visits being shorter. When it is only a brief office visit, only a few things may be tested to decide if medication is helping, or if changes are required. While the examination is very informative and can usually result in a definite "yes" or "no" to the question of whether you have PD, some of you may have experienced exams where the neurologist is not certain and asks you to return in a few months or a year to see if your physical exam changes.
Despite all the advances that have been made in the field of neurology, the examination remains essential.
Neurologist Dr. Glen Ackerman, M.D., is a past Chairman of the Michigan Parkinson Foundation Professional Advisory Board and is a cur¬rent Member. He is Assistant Professor of Neurology, Michigan State University School of Human Medicine and School of Osteopathic Medicine, and is Head of its Movement Disorders Clinic.