Neuromuscular Microstimulators

Chris Morino BME 281

Neuroplasticity The brain ability to actively

rewire itself in response to external stimuli

This ability inspired people to create the microstimulator

History 1960 Liberson’s drop foot stimulator 1989 AMF began working on the mircostimulator late 1990s Mayo clinic performs Occipital nerve stimulation

for medically refractory headache pain 2008 AMF develops working prototypes of injectable

microstimulators without exoskeleton system

Old New

Old verse new

How does it work? Send little electrical shocks to muscles to induce movement Contains the pulse generator and the electrode together in a

package the size of a matchstick Controlled wirelessly with a cell phone like controller that tells

each independent implant when to stimulate

Inside look

Different types

How is it implanted? Bion insertion tool Makes the small implants

into precisely localized sites within the body a simple task for surgeons

Reason for Microstimulartors Over 32 million (70% women) suffer from migraines 11, 000 suffer a spinal cord injury 750,000 people suffer a stroke 5.3 million with after affects of traumatic brain injury

What they have to offer Can be implanted directly

into the damage muscle tissue

Helps reteach the brain how to reuse damaged muscles

No side affects for having it implanted for long period of time

Experimentation Alfred Mann Foundation funded research for this device Dr. Ross Davis responsible for the implantation Dr. Daniel Merrill consultant on the research Goal: to examine the effect of home based electrical

stimulation using closed- loop control of implanted microstimulators on upper limb function

Results 5 out of 6 patients said it changed their lives Over a 12 week period patients had dramatic change Improved their function with the impaired upper limbs Although external components were inconvenient for patients

Availability The internal device is unfortunately restricted to

investigational use only Although similar experiments were performed in the United

Kingdom using the internal device Results came back positive after 12 weeks of stimulating

Future Working on stimulators that can also sense changes in

pressure, limb angle, muscle activity and temperature Application for lower extremities Get past the investigative stage in the United States to truly

tap the potential this device is capable of.

References URI BME 281 BME Seminar II <www.ele.uri.edu/courses/bme281>. Burridge, Jane H., Ruth Turk, Daniel Merrill, Bridget Dibb, Ann-Marie

Hughes, Owen Sparrow, Helen Roberts, and Ross Davis. "A Personalized Sensor-Controlled Microstimulator System for Arm Rehabilitation Poststroke. Part 2: Objective Outcomes and Patients' Perspectives." Neuromodulation: Technology at the Neural Interface (2010): No. Print.

"Microstimulators Hold Promise for Some Medically Refractory Headaches."Microstimulators Hold Promise for Some Medically Refractory Headaches. N.p., n.d. Web. 19 Sept. 2013.

http://aemf.org/our-research/current-focus/neuromuscular-disorders/ "SpringerImages." SpringerImages. N.p., n.d. Web. 19 Sept. 2013. http://link.springer.com/article/10.1007%2Fs10439-009-9739-5