Neuroplasticity and PPMS

Q: On the neurology congress in Philadelphia in 2014 there was a topic about neuroplasticity and PPMS.

http://conferencecenter.msworld.org/american-academy-of-neurology-2014/day-three-at-aan/study-on-therapy-for-progressive-multiple-sclerosis

Did they continue to find the influence of neuroplasticity on PPMS patients?

A: There were many exciting findings related to MS research shared at the American Academy of Neurology in May 2014.  Of great interest to many were reports specifically related to treatment for people with progressive MS (PMS).  Dr. Gary Cutter, Professor of Biostatistics at the University of Alabama, briefly spoke about preliminary findings related to  non-pharmacologic therapy for improvements in the arm and hand, as well as legs, in people with PMS. 

In this study, Dr. Victor Mark and colleagues examined the effects of a rehabilitation strategy called “constraint-induced movement therapy”.  This approach has been studied most extensively in people with paralysis or weakness due to stroke.  Constraint-induced therapy involves constraining, or tying down, the less affected arm or leg to force the affected (paralyzed or weak) arm or leg to work for a certain period of time.  The idea is that the more affected limb is limited in function in part because the individual has learned to not use that limb, therefore causing it to get worse.  In constraint-induced therapy, restricting activity to the more affected limb forces the nervous system to work to restructure itself and restore function in the pathways that cause movement.  In other words, by using this approach of forcing the affected limb to work, this is causing neuroplasticity in this system, and hopefully restoring function.

Five people (study participants) with either primary or secondary PMS were treated with constraint-induced therapy with direct supervision of a therapist 3 hours per week for 2 to 10 consecutive weeks (a total of 30 hours of therapy).  Study participants performed repetitive tasks that were functionally relevant to them, such as stacking cups or turning items, and tasks were increased in difficulty by the study therapist as the participant demonstrated improvements in performing the tasks.  Participants also wore a padded mitt on the constrained limb for a target of 90% of waking hours on training days.  The investigators measured arm function before and after the 30 hours of treatment.  They also redid the measures 4 weeks after the last therapy session.

Participants demonstrated an improvement in their movement activity log, which measured their real life use of their arm and hand.  They also reported a decrease in fatigue with use of their arm and hand.

It is important to note that there were no measures of what was happening in the nervous system.  For instance, there were no measures of brain or spinal cord activity before and after the therapy.  Thus, it is not clear if changes in function were matched by changes in the nervous system, and due to neuroplasticity.

It is also important to note, and specifically as it relates to this question, that the changes that they saw were still there at 4 weeks post-treatment.  However, they were not measured again and it is therefore not clear if the changes last much longer than that.  Further study is required to determine how long these changes will persist in people with PMS

Finally, this study had only 5 participants, and a larger study is important to see how much these findings can be generalized to the larger population of people with PMS.  However, it is particularly exciting that some people with primary and secondary PMS were able to demonstrate improvements in function.  This challenges the traditional dogma that people with moderate to severe MS cannot benefit from rehabilitation. 

-Deborah Backus, PT, PhD, Shepherd Center

Reference:

Mark, V. W., Taub, E., Bashir, K., Uswatte, G., Delgado, A., Bowman, M. H., ... & Cutter, G. R. (2008). Constraint-Induced Movement therapy can improve hemiparetic progressive multiple sclerosis. Preliminary findings. Multiple Sclerosis.