One of the first steps in receiving an MS diagnosis is a neurological exam. Neurological exams can also help track the progression of MS. Neurological exams are part of the overall physical exam done by a doctor. Just like a doctor checks your heart and lungs by listening to them with a stethoscope, they can also check your nervous system.
An MS neurological exam
People with MS may have abnormal findings on a neurological exam. However, in some cases, MS brain lesions may be in areas that do not directly impact things tested on the exam. For this reason, brain imaging is helpful to use together with a full neurological exam.
Common things tested in a full neurological exam include:
- Cranial nerves
- Motor nerves
- Sensory nerves
- Autonomic nervous system
- Mental status
We have 12 pairs of cranial nerves. These nerves control many functions of the head and neck. Some are sensory nerves. An example of this is cranial nerve 1 (the olfactory nerve), which controls our sense of smell. Cranial nerve 2, the optic nerve, controls our vision. Others are mainly motor nerves. These include cranial nerves 3, 4, and 6, which control the movements of the eye.
Each cranial nerve has its own function. Working cranial nerves allow us to feel and move our face, chew, swallow, and talk. It is not uncommon for 1 or more cranial nerves to be affected by MS. Your doctor will test each nerve individually and look for anything unexpected.1
Motor nerves are usually tested by assessing the body’s strength. Your doctor will apply pressure to your arms, legs, and feet and ask you to push back. Your doctor can sense how much force you can use to resist their pressure and see if there are any differences between each arm or leg.
Sensory nerves can be tested in several ways. Your doctor may ask if you can feel their touch on different areas of your arms or legs. They may also ask if this sensation is the same on both sides of your body. Another way to test sensation is to determine whether you can tell the difference between dull pressure and sharper touch.1,2
Your doctor may also test for Lhermitte’s sign. This is an electrical sensation that travels down your spine and into your limbs when you bend your head forward. This may feel like a buzzing or tingling feeling. This is a common finding in people with MS.3
Reflexes are involuntary movements of different parts of your body. An example is the patellar reflex. When a doctor taps a reflex hammer underneath your knee, your foot kicks outward. This movement happens immediately and without you needing to think about it. Reflexes that are working normally (also called intact) are signs of good neurological function. Your doctor will use a reflex hammer to check several common reflexes in the elbows, knees, and ankles. They will make note of any weak, absent, intense, or unequal reflexes from side to side.2
Another reflex that is commonly tested is the Babinski reflex. When the bottom of the foot is scraped from heel to little toe, the toes should all curl inwards. In an abnormal Babinski reflex, the toes all fan outwards instead. An abnormal Babinski reflex can be a sign of underlying neurological issues.
Coordination can be tested by asking a person to touch a finger to their nose and then to a doctor’s finger in front of them. The doctor will continue to move their finger after each touch to see if they can be followed. This is called the finger-to-nose test. Other tests involve quickly flipping the hands back and forth between palm side up and palm side down as well as touching the heel of one foot to the knee of another and sliding the foot up and down the leg.
Your doctor will also watch the way you naturally walk to assess your coordination. This is called checking your gait. They may also ask you to walk on your toes or heels to watch different types of walking. They will look for signs of abnormal movements, changes in speed, and any issues with balance.2
Autonomic nervous system
Our nervous system also plays a role in other functions. The autonomic nervous system (ANS) plays a role in our heart rate and blood pressure. Your doctor will look at your vital signs, the way your pupils dilate in response to light, and more to assess your ANS.2
Throughout the entire exam, your doctor can pay attention to your mental status. This includes your attention, memory, mood, communication, and more. They may ask orientation questions. Examples of this include asking what your name is, where you are currently located, and what day of the week it is. They may also ask you to repeat or remember a series of words, objects, or colors.2
When used with a good personal account of symptoms, brain imaging, and other testing, a neurological exam can be a great tool for diagnosing or monitoring MS.