Left side versus right side

[JeffS]

Hi, I am right handed and right domonate. I have the same issue. The issue is because through years you have worked your right arm more than the left, so the muscle has broken down quicker.

[mike-huddleston]

Interesting question. It may be overuse as both you and Jeff suggest, or it could be that you’ve had a higher rate of loss with the motor neurons on the now weaker side. Or a combination. It’s odd that we all have some similarities and some differences in how SMA progresses. Our Venn diagrams are quite different between different sets of patients. The old YAMMV applies.

For me, I’m right side dominant and was an ambulatory Type 3 until about 10 years ago. My right side has always been stronger than my left side. And to this day, major muscles like my right thigh and hamstring, as well as my right bicep and triceps, are larger and stronger than my left ones. So, make of that what you will. 🙂

You also mention the myostatin inhibitors that should be approved later this year by the FDA. That will obviously be more effective in the muscles with more and still viable motor neurons, so this is very exciting. I’ve mentioned it previously in comments, but the big game changer will be when we can get motor neurons to either be newly generated or regenerated. This is critical since currently we are born with the number of motor neurons we will have for our lives and until that changes, all treatments, amazing as they are, have limited effectiveness due to this motor neuron loss. I’ve read there is work on anthrobots in labs that has shown possibilities and have also had recent discussions about peptides improving nerve function.

These are indeed very exciting times and I continue to be thankful that there are hundreds, if not thousands, of people working on our and other conditions that will improve our lives. Progress is happening and as Andy Dufresne says in The Shawshank Redemption, “Hope is a good thing, maybe the best of things”.

[jsi]

I have SMA 3 I am right handed and over 65 years old. My right side side is stronger than my left.The difference in strength seems to be more significant as I age. I walked with a walker until 18 months ago. I am in wheelchair full time now.

[chrisr]

Thanks for the info. I spoke to my neurologist this week, and crispr is the cure. It looks like it will be available in 5 years

[chrisr]

Also the inhibitors will help repair muscles because I used my right side to transfer a lot before Spinraza and it caused more wear and tear on my body

[mike-huddleston]

I just realized who this is. Should have paid more attention or realized. 🤨

Although this may be one of the benefits of myostatin inhibitors, the biggest benefit whether for repair or strength gains is somewhat, if not largely, dependent on the viable/salvageable motor neurons. The weakness in any area may be related to overuse and/or higher motor neuron loss for that area/muscle group or some unknown combination of the two. Neurologist can speculate or hypothesize about which is the more likely cause since we all progress in different (albeit similar) ways, but they cannot answer this definitively. If it’s overuse, the repair by and building strength is more likely than if the cause is higher motor neuron loss.

Regardless, I’m looking forward to the FDA approval later this year and hoping insurance doesn’t cause too much heartburn in approving this in combination with other available treatments of Evrysdi or Spinraza.

[alyssa-silva]

Just had to pop in here to say that the insurance-induced heartburn is real. I’ve never heard anyone say it like that before lol. I love it.

[mike-huddleston]

Sad but true, Alyssa. And I have little doubt that most, if not all, of us here have experienced this to some degree.

[diana-a]

I’m also type 3 with 4 copies of SMN2. I’m 63 yrs old and ambulatory using a walker. I’m right hand dominant and my right side has always been stronger. Going up the stairs to lifting heavy objects, etc. were always accomplished using my right side. My left side is getting weaker I feel by the day. My left hip is unreliable and I lose my balance easily. My fear of falling is overwhelming at times. I’ve been on Spinraza since Fall 2017 and am looking forward to a higher dose as well as a muscle therapy. It can’t come soon enough. I’ve been using a walker for about 3 years.

[mike-huddleston]

Very similar experience that I can completely relate to. 62 years old, Type 3 with 4 copies as well. I was ambulatory until 2015 and now use a power wheelchair. Much stronger on my dominant right side. I do PT twice a week (1 land and 1 pool) and have a rigorous HEP in an effort to maintain as much as possible until myostatin inhibitor and other future treatments become available. Not waiting on them, but thankful they’re on the way. Still, where I’ve apparently lost more motor neurons, the weakness progresses more quickly. When I was ambulatory, especially the last few years with Lofstrands, the worry or concerns of falling could be overwhelming and mentally exhausting at times. I actually started reducing some of my activities due to this concern. It’s real Diana, so I so feel this comment/concern.

Personally, I couldn’t use a walker (tried various devices with a PT) because I’m almost 6 feet tall with long-ish legs and when I “threw” them, I kept kicking the walker’s legs. Not a good outcome for me.