Guest guest Posted January 20, 2004 Report Share Posted January 20, 2004 Sandy, There is not yet a test that determines whether one has ALS or PLS. (They're working on it.) Currently, the diagnosis is one of exclusion--every other known cause of the symptoms must be ruled out to arrive at a diagnosis. Generally, PLS affects only the upper motor neurons (UMN's). What are UMN's? The cell body of an UMN resides in the brain. It has a long tail (an axon) that extends down the spinal cord. The axons of UMN's that control the legs extend far down the spinal cord. Those that control the arms extend only to about the shoulders. There are also lower motor neurons (LMN's). The cell bodies of these nerve cells reside in the spinal cord, at the end of UMN's. They also have axons. A LMN axon extends out of the spinal cord to the various muscles of the body. A signal to move the big toe begins in the brain (in the cell body of an UMN) and travels down the UMN's axon in the spinal cord to its' end. There it meets the cell body of the LMN. The signal is sent from the end of the UMN to the cell body of the LMN. That signal then travels down the LMN's axon to the big toe. Once at the muscle for the big toe, the nerve signal is sent to activate the muscle. Generally, only the UMN's are affected in PLS. ALS affects both the UMN's and the LMN's. However, sometimes PLS can also affect LMN's. The affect is usually not significant. The diagnosis of both ALS and PLS begins by ruling out all other causes of the symptoms presented by a patient. To distinguish ALS from PLS, neurologists look for significant muscle wasting. This is a symptom of ALS. They also conduct EMG exams to detect damage of the LMN's. Mark > I was just wondering, how can a doctor determine if you have pls or als, is there a test that determines this? Also what is the difference between the two? > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 20, 2004 Report Share Posted January 20, 2004 > Sandy, > A signal to move the big toe begins in the brain (in the cell body > of an UMN) and travels down the UMN's axon in the spinal cord to > its' end. There it meets the cell body of the LMN. The signal is > sent from the end of the UMN to the cell body of the LMN. That > signal then travels down the LMN's axon to the big toe. Once at the > muscle for the big toe, the nerve signal is sent to activate the > muscle. > > Generally, only the UMN's are affected in PLS. ALS affects both the > UMN's and the LMN's. However, sometimes PLS can also affect LMN's. > The affect is usually not significant. Mark, my right side is my affected side....I haven't been able to move either my right foot or any toes on my right for maybe 5 years. is this considered " not significant " ? my neuro knows, but has never said anything about it. does anyone else have this problem? i just assumed it was fairly normal for PLS. maggie Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 20, 2004 Report Share Posted January 20, 2004 Good write up, in order to picture this I always tell people to view ALS/PLS as a scale. On the far left is the very aggressive ALS, your told you have ALS and in 5 months your dead. Far right is the people who have PLS but after 20 years of it, they are just starting to use the cane. The messy part comes in the middle, people with ALS but live 30+years and right next to them is the very aggressive PLS. Hopefully this helps to see why it's so difficult sometimes to determine between the two. dale Re: pls-als > Sandy, > > There is not yet a test that determines whether one has ALS or PLS. > (They're working on it.) > > Currently, the diagnosis is one of exclusion--every other known > cause of the symptoms must be ruled out to arrive at a diagnosis. > > Generally, PLS affects only the upper motor neurons (UMN's). What > are UMN's? > > The cell body of an UMN resides in the brain. It has a long tail > (an axon) that extends down the spinal cord. The axons of UMN's > that control the legs extend far down the spinal cord. Those that > control the arms extend only to about the shoulders. > > There are also lower motor neurons (LMN's). The cell bodies of > these nerve cells reside in the spinal cord, at the end of UMN's. > They also have axons. A LMN axon extends out of the spinal cord to > the various muscles of the body. > > A signal to move the big toe begins in the brain (in the cell body > of an UMN) and travels down the UMN's axon in the spinal cord to > its' end. There it meets the cell body of the LMN. The signal is > sent from the end of the UMN to the cell body of the LMN. That > signal then travels down the LMN's axon to the big toe. Once at the > muscle for the big toe, the nerve signal is sent to activate the > muscle. > > Generally, only the UMN's are affected in PLS. ALS affects both the > UMN's and the LMN's. However, sometimes PLS can also affect LMN's. > The affect is usually not significant. > > The diagnosis of both ALS and PLS begins by ruling out all other > causes of the symptoms presented by a patient. To distinguish ALS > from PLS, neurologists look for significant muscle wasting. This is > a symptom of ALS. They also conduct EMG exams to detect damage of > the LMN's. > > Mark > > > I was just wondering, how can a doctor determine if you have pls > or als, is there a test that determines this? Also what is the > difference between the two? > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 20, 2004 Report Share Posted January 20, 2004 Thank you Maggie and Mark, Thank you for all the info. My right side is mostly effected. Right leg,foot,shoulder,arm and hand. So I am just a little confused with the diagnosis of PLS. sANDY Re: pls-als > Sandy, > A signal to move the big toe begins in the brain (in the cell body > of an UMN) and travels down the UMN's axon in the spinal cord to > its' end. There it meets the cell body of the LMN. The signal is > sent from the end of the UMN to the cell body of the LMN. That > signal then travels down the LMN's axon to the big toe. Once at the > muscle for the big toe, the nerve signal is sent to activate the > muscle. > > Generally, only the UMN's are affected in PLS. ALS affects both the > UMN's and the LMN's. However, sometimes PLS can also affect LMN's. > The affect is usually not significant. Mark, my right side is my affected side....I haven't been able to move either my right foot or any toes on my right for maybe 5 years. is this considered " not significant " ? my neuro knows, but has never said anything about it. does anyone else have this problem? i just assumed it was fairly normal for PLS. maggie ------------------------------------------------------------------------------ Quote Link to comment Share on other sites More sharing options...
Guest guest Posted January 21, 2004 Report Share Posted January 21, 2004 Maggie, In PLS with some LMN involvement I have not heard of any observable muscle wasting. The LMN damage that I heard of was observable at autopsy (other causes), and bt EMG. That you can't move your right foot could be caused by damage to (1) UMN's, (2) LMN's or (3) both UMN's and LMN's. If the damage is to UMN's you have PLS. If it is to LMN's, you have spinal muscular atrophy. If it is to UMN's and LMN's, you have ALS. ( This assumes that all other possible causes of the symptoms have been ruled out). I'm guessing that you have a PLS diagnosis (since you're here). Your neurologist has probably found no LMN damage. Mark Mark .. > > Sandy, > > > A signal to move the big toe begins in the brain (in the cell body > > of an UMN) and travels down the UMN's axon in the spinal cord to > > its' end. There it meets the cell body of the LMN. The signal is > > sent from the end of the UMN to the cell body of the LMN. That > > signal then travels down the LMN's axon to the big toe. Once at > the > > muscle for the big toe, the nerve signal is sent to activate the > > muscle. > > > > Generally, only the UMN's are affected in PLS. ALS affects both > the > > UMN's and the LMN's. However, sometimes PLS can also affect > LMN's. > > The affect is usually not significant. > > > Mark, > my right side is my affected side....I haven't been able to move > either my right foot or any toes on my right for maybe 5 years. > > is this considered " not significant " ? my neuro knows, but has never > said anything about it. > > does anyone else have this problem? i just assumed it was fairly > normal for PLS. > > maggie Quote Link to comment Share on other sites More sharing options...
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