EVALUATING PATIENTS FOR NEUROMUSCULAR DISEASE: TOWARD A TIMELY DIAGNOSIS AND/OR REFERRAL

Chapter 2: cranial nerves

Dr. Mark Tarnopolsky: What we are going to do is just take a look first and you can see that there is no ptosis, some disorders like OPMD, myasthenia there can be ptosis. What I am going to do is just put my hand here and move over, look up, down. We are moving in an H. Up and down. You did not see double through any of that did you?

Patient: No, not at all.

Dr. Mark Tarnopolsky: No, so we did not see any ophthalmoparesis nor did she report any diplopia, certainly things like OPMD, we see ptosis but not ophthalmoparesis. With things like mitochondrial disease, there can be ophthalmoparesis or things like Myasthenia gravis. Now, we are going to take a look at the eyes and this does not need to be onerous with the ophthalmoscope. First what we do is just take a look at the pupillary response, so just look straight ahead. And they are nice and symmetric, going from 4 millimeters to 2 and now we are going to take a look at the cataracts and fundi and this can be done very quickly. First when you look at cataracts you usually put it on Green 7 on the scope and if I can get you just to sit straight and look straight ahead. I am just going to touch your shoulder here so it is right eye to right eye look off into distance and then usually if you go in and out with a Round Green 7 if there is cataracts you will see them come into view but we did not see anything there, so there is no cataracts. We can see cataracts in certain things like mitochondrial disease. We can see this in different types of muscular dystrophy such as myotonic dystrophy type 1 and type 2. I am just going to touch your shoulder, left eye to left eye looking straight ahead and in and back, no cataracts.

Then to look at the fundi put it on 2 and look straight ahead. We can see the optic nerve and the back of the eye. No retinitis pigmentosa. Everything looks good. Things like mitochondrial disease we can see optic atrophy and other things. If you do not feel comfortable doing this exam, that is fine, but if someone has visual symptoms, refer them to ophthalmology. Just look straight ahead, and the disc looks good and there is no retinitis pigmentosa. I will put that away. Any swallowing issues at all?

Patient: No.

Dr. Mark Tarnopolsky: None whatsoever. If she did have swallowing issues we would take a look at the throat. Just using your otoscope, open up your mouth, big ah, and you can see that her palate moves symmetric and just listening to the voice as part of the examination. Patients who have a weakness in the back of the throat, such as OPMD or myasthenia will often have a nasal voice and Erin does not have any issues like that.

Chapter 3: motor examination

Dr. Mark Tarnopolsky: We will move on to the motor examination. The main thing is to check the bulk, the tone and the strength. Looking first of all at the bulk, have you lost any muscle mass anywhere? Like if has any muscle shrunk?

Patient: No.

Dr. Mark Tarnopolsky: You do not feel that anything has gotten thin or anything?

Patient: No.

Dr. Mark Tarnopolsky: Again, we would just to take a look to see if there is any atrophy at the calf muscles, which she does not have, other calf here there is no asymmetry. Calves can be enlarged in some of the muscular dystrophy such as Becker's or Limb-girdle dystrophy. We see no changes in her muscle bulk. We will take a quick look at tone, so that I can just get you to relax. That is good. Her tone is nice and normal. With upper motor neuron findings, we would get a catch and release, if it is a cortical spinal tract issue. If there is Basal Ganglia issues, there will be stiffness in the tone which we can see in kids who are floppy and hypotonic with muscle disease, we call that hypotonia, which is a form of weakness.

Now we are going to take a look at the proximal muscles. If you can hold your arms up, push up, and you were trying hard there, Erin?

Patient: Yeah, trying hard.

Dr. Mark Tarnopolsky: There was no pain involved?

Patient: No pain at all.

Dr. Mark Tarnopolsky: Okay, so painless weakness is real weakness. Sometimes if people have a shoulder problem, it will appear that they are weak and that is more due to the pain. There is definitely some weakness there that we can see, Erin. Can you hold your arms like this? Pull your arms up. Okay. All right. A little bit of weakness there. And push down. Okay. That felt weak too, right?

Patient: A little bit, yeah.

Dr. Mark Tarnopolsky: Good. It is arm flexion and extension and she has a little bit of weakness. The weakness is graded from essentially 0 to 5. 0 means there is no contraction at all, 1 is a flicker of contraction, 2 would mean that you can contract the muscle but you have to eliminate gravity. For example, she was able to pull-up and give me some resistance but if she was very weak and we put her arm like this, now try and bring your arm in, good, so if she could not bring the arm up like this but could like this that would be a grade 2 because I have eliminated gravity in this situation. Grade 4 is a little subjective. 4 plus means almost full power, 4 means that there is a loss of power, 4 minus means it is barely giving you some power. Erin’s strength there in the proximal muscles was a Grade 4.

Now, we are just going to check for some scapular winging. Put your arm forward and push-up, push-up, push-up and the scapula actually did come off the back there and you can feel that coming up or if the patient did not have a gown on you could see the scapula winging. We can see that in Pompe disease, we can see that in FSH dystrophy so we do have some weakness there. Now, let us take a look on this side and just push straight up push, push, push and there is some scapula winging there. There is definitely proximal weakness. Now, let us take a look distally. Can you squeeze my fingers strong as you can strong, oh that is good and strong okay. I am going to ask you now to squeeze strong and let go as fast as you can, let go, good. Her distal strength is totally normal and there was no myotonia. There is a thing called myotonic dystrophy which I do not think you have. Type 1 would definitely show stiffness in the hands. We will just do one another quick check. Spread your fingers apart push, push nice and strong push so distal myopathies and neuropathies which show weakness distally, her strength is normal but we are seeing some proximal weakness.

Now, let us turn our attention to the lower extremities and finish the motor exam. Bring your knee up. Can you get up to my hand push, push okay all right let us try it on this side, bring it up push, push so she can just barely get it up. In this side she could not move through gravity so that would be a 2, on the left she can move through gravity that is a 3. Clearly, we have some weakness there. Try and push your legs apart, okay that is nice and strong. That is abduction taking away, bringing together is adduction adding it back to the body.

She clearly demonstrates some weakness with hip flexion and adduction but not abduction. We often see that in different muscle disorders. Now, we can take a look at the more distal muscles down here. Just relax pull the toes up as strong as you can pull, good, and that is nice and strong, and this one here pull, so we did see some weakness there where we can test other muscles but to a first approximation in family medicine office or internal medicine those are really the main muscles that we would check. What we see is definitely some proximal weakness and we are going to just check a few other things.

Chapter 4: reflexes, sensory exam and gait

Dr. Mark Tarnopolsky: Next part of the exam is the reflexes. I will just take a look let it go nice and loose and this is the Brachioradialis you can see how nice and perfect that is. Really, that is all you need to do unless somebody had neck pain or weakness on one side of the arm showing that the reflexes are normal. In the lower extremities here, let it go loose and we still can generate a reflex and we have a reflex it is nice and normal down here. Reflexes are zero if they are completely absent. If we could not get it the first time we can distract people and this is Grade 1. For example, if I could not get the reflex here I could ask her to take your hands and pull them apart and then if I could get the reflex that would be a Grade 1 and that is called the Jendrassik maneuver but her reflexes are normal. In patients with muscle disease if they are getting very weak eventually they will lose the knee reflex because the muscles are just too weak to generate a reflex. In clinical practice, we really only need to do the Brachioradialis, knee jerks and ankle jerks. Ankle jerks are lost early in neuropathy and lost late in myopathy in the knees.

Sensory examination, Erin told us that there was no problems at all with numbness or tingling, so we just are going to do a quick screen. Sometimes patients with muscle disease and other neurologic disorders can have deficiencies. Things like Vitamin D deficiency, Vitamin B-12, or even prediabetes which can affect the nerves. With the tuning fork, it has to be a 128 not a 256 when you are testing this. What we are going to do is just let your legs go loose. Do you feel the buzz down here?

Patient: Yes.

Dr. Mark Tarnopolsky: Good. Tell me when it stops.

Patient: Stops.

Dr. Mark Tarnopolsky: Okay. Perfectly normal. We will just check it here. Do you feel the buzz?

Patient: Yes.

Dr. Mark Tarnopolsky: Tell me when it stops.

Patient: Stop.

Dr. Mark Tarnopolsky: Perfectly normal. We are just going to check sensation now. She does not have any issues at all with numbness and tingling. Just a quick screen can be as simple as taking your tuning fork, which is cold, touching it here. Does that feel cold?

Patient: Cold.

Dr. Mark Tarnopolsky: Cold up here?

Patient: Cold.

Dr. Mark Tarnopolsky: Yeah, so she can feel the cold there, so we are testing the two main sensory pathways. Pain and temperature is carried by one fiber and vibration and proprioception is carried by another. Those are both perfectly normal. We would not expect those to be abnormal in a muscle disease. I do not believe that you have a nerve disease because usually these would be affected with a peripheral neuropathy.

Either with your tuning fork, you could do it here or with your reflex hammer. You could also just scratch the toes and just a bit of withdrawal response. But if she had the corticospinal tract issues the toe would go up. For example, if there was a stroke or a spinal cord problem, and the toes will usually fan out, but her toes were going like this, but not up. That is normal. Usually they will stay the same or sometimes curl down. The abnormal response is toe up and the toes fan out and you do not have any issues there at all. Okay. What we have established is that there is definitely some proximal weakness there, you did tell us that it was hard sometimes to get out of the chair, to get up from the ground.

You said that your gait was off a bit too. I think what we will do now is just if you could sit in this chair just a little bit lower and we will just see how you get out of the chair and take a few steps for me please.

Patient: Okay.

Dr. Mark Tarnopolsky: I will have you sit there. Good. I will just stand over here and what I would like you to do whenever you are comfortable just try and stand up the way you normally would at home and then if you could just take a couple of steps for us.

Patient: Okay.

Dr. Mark Tarnopolsky: Go ahead.

Patient: Okay.

Dr. Mark Tarnopolsky: Okay that is great. Have you come back and then just sit down. Okay. That is the gait that people were talking about, is that correct?

Patient: That is right.

Dr. Mark Tarnopolsky: Okay. What we saw is that getting up from a chair, because of the proximal weakness that we saw, it was impossible to use the strength just to stand up. Erin, what you were doing is you had to put your hands down to compensate and get yourself up from the chair and because these muscles are weak here, when you are starting to walk, the hips are dropping a little bit and it is giving you a bit more of a sway.

Chapter 5: examination conclusions

Dr. Mark Tarnopolsky: Looking at the complete package with the weakness that you have had, the muscle enzymes being elevated, weakness in the shoulders and the hips, there is a variety of muscle disorders I think that we need to look into. I am not seeing any toxins, drugs that could have done this. So we have to think about things that could be genetic. Good news is most of these with your negative family history, do not worry about your kids. Usually these are things where your mom and dad would carry the bad gene. Things we are going to look into are limb-girdle muscular dystrophies and a thing called Pompe disease. Pompe disease can look like the limb-girdle dystrophies and there is a specific treatment for that. That is why we want to really get the diagnosis for you. Also, I think important for you to know because once we have the gene diagnosis, prognosis, family risk and all of these things we can talk about, but most importantly for you, what can we do to help treat these things. Good. Thanks.