Myomo Therapeutic Theory Overview
For many decades, it was believed that once an individual had a stroke there was a three to six month window of recovery. After that period passed, whatever impairments remained were accommodated by substituting with the non impaired side or using an arsenal of gadgets used to replace function. Approximately fifteen years ago, neuroscientists discovered that recovery time is not absolute. With the correct types of external stimuli and dosing, areas of the brain can create new neuronal connections to undamaged areas of the brain and recovery of lost motor function can still occur. This phenomenon is what scientists refer to as neuroplasticity, and it persists years even decades post injury.1
One of the most significant contributors to Neuroplasticity is Randolph J. Nudo, Director of the University of Kansas Landon Center on Aging and Professor in the Department of Molecular and Integrative Physiology. In one area of his research, Nudo’s team damaged an area of the brain in rhesus monkeys, paralyzing one side of the body similarly to what would happen in a stroke. He then tied down their non-impaired side. The monkeys either had to figure out how to use the weakened side to eat or starve. Many of them figured out how to eat. Nudo took brain images both before and after the damage was inflicted. Significant changes in the activity centers of these monkeys were observed. The damaged side that once provided the control for the function of using the weak arm was still damaged. However, new areas on the opposite side of the brain now had activity and new neuronal connections, leading to an exciting discovery that the brain was somewhat plastic and different areas could be trained to learn new tasks and re-establish function for an area of the brain that was no longer functioning if it was “forced” to do so.2
This led to a new form of therapy called “Constraint Induced Movement Therapy,” or “Forced Use Movement Therapy.” The person who is credited most with this approach is Dr. Edward Taub, a neuropsychologist from the University of Alabama. Dr. Taub and his medical team found a way to create a very structured, intense physical and mental therapy program. The patient would wear a mitt on the strong arm, preventing its use for 6 hours a day, and was forced to perform activities of daily living (ADLs) with the impaired side during this time. The patient would ideally be in a therapy setting under the guidance of a therapist for these 6 hours. This intense regimen of therapy is sometimes referred to as Repetitive Task Practice/Training. After several weeks of Repetitive Task Practice, both subacute (patients who have had recent stroke) and chronic (patients who have had a stroke in the past) patients showed statistically significant changes in function.3 This approach is one of the few approaches in the neuro-rehabilitaiton space that has been validated by a large randomized multi-site control trial called XCITE.4
Although this approach was extremely encouraging to professionals in the neuro-rehabilitation field, it was impractical from a staffing and reimbursement standpoint. In the United States, the average therapist treats anywhere from 1-3 patients per hour. The therapy is typically reimbursed in 2-4 unit increments under the CPT codes of neuromuscular re-education or therapeutic exercise. Six hours of patient/therapist interaction was extremely impractical from both a payer and provider vantage point. Several clinics tried to start cash-based Constraint Induced Movement Therapy Programs or Group Constraint Induced movement therapy programs because they believed in the theory and the research, but they needed to get paid for their treatment time.
In the meantime, several other researchers were looking for more cost-effective ways to deliver the same benefits and to offer the intervention to a larger group of patients since post-stroke patients who are impaired and have wrist extension (a criteria for Constraint Induced Movement Therapy), are in the small minority of 5-15%. The approaches they came up with involved Repetitive Task Practice similar to that performed by Nudo et al. but done in the home setting. These approaches all had a single element in common with the Constraint Induced Movement Therapy group - force the individual with the impairment to use the impaired side. However, the time commitment was shorter and the patient could perform the activities in their own home, eliminating the need for costly therapy hours. The key consistent element involved the patient performing hundreds if not thousands of repetitions of a given task using the weak side.5,6
Notably, Rosenstien et al. and Frick et al. have determined that Repetitive Task Practice is especially helpful in improving functional tasks and motor function, specifically when used in conjunction with new Robotic Technology. 8,9 Myomo’s technology allows the patient a more self-guided, yet intuitive way to use the involved extremity - utilizing the concepts of CIMT and Repetitive Task Practice. Similar to a myoelectric upper extremity prosthetic, the biofeedback allows self-initiation of movement. The poweredd assistance, replaces the need for a therapist to be standing over the patient at all times. The therapist can then use their expertise to set up the correct programs and levels of assistance for the patient and leave the grunt work of lifting the limb to the device. As patients become skilled at controlling the orthosis and progress from closed chain to more complex open chain activities, they are able to use the device to accomplish activities that previously could not be accomplished.
Nudo RJ, Plasticity. NeuroRx. 2006 Oct;3(4):420-7.
Dancause N, Barbay S, Frost SB, Plautz EJ, Chen D, Zoubina EV, Stowe AM, Nudo RJ.
Extensive cortical rewiring after brain injury. J Neurosci 2005;25:10167–10179.
Taub E, Uswatte G, King DK, Morris D, Crago JE, Chatterjee A. A placebo-controlled trial of
constraint-induced movement therapy for upper extremity after stroke. Stroke. 2006;37:1045–1049.
Wolf SL, Winstein CJ, MillerJP, Taub E, Gitendra U, Morris D, Guiliani C, Light K, Nichols-Larsen
D. Effect of Constraint-Induced Movement Therapy on Upper Extremity Function 3 to 9 Months After Stroke: The EXCITE Randomized Clinical Trial JAMA, November 1, 2006; 296: 2095 — 2104.
Wu CY, Chen CL, Tsai WC, Lin KC, Chou SH. A randomized controlled trial of modified constraint-induced movement therapy for elderly stroke survivors: Changes in motor impairment, daily functioning, and quality of life. Arch Phys Med Rehabil. 2007;88:273–278.
Page SJ, Levine P, Leonard AC. Modified constraint-induced therapy in acute stroke: A randomized controlled pilot study. Neurorehabil Neural Repair. 2005;19:27–32.
Stein J., Narendran K., McBean J., Krebs K., Hughes, R. Electromyography-Controlled
Exoskeletal Upper-Limb-Powered Orthosis for Exercise Training after Stroke. Am. J. Phys. Med. Rehabil. Vol. 86. No. 4. 2007 Erratum April 2008.
Page SJ, Hermann V, Levine P, Lewis E, Stein J, DePeel J. Portable neurorobotics for the severely affected arm in chronic stroke. J Neurol Phys Ther 2011 Mar;35(1):41-9.
Lum PS, Burgar CG, Shor PC, Majmundar M, Van der Loos M. Robot-assisted movement training compared with conventional therapy techniques for the rehabilitation of upper-limb motor function after stroke. Arch Phys Med Rehabil. 2002;83:952-959.
Rosenstein, L, RIdgel AL, Thota A. Effects of combined robotic therapy and repetitive task practice on upper-extremity function in a patient with chronic stroke. Am J Occ Ther. 2008; 62(1): 28-35.
Frick EM, Alberts JL. Combined use of repetitive task practice and an assistive robotic device in a patient with subactue stroke. Phys Ther. 2006; 86: 1378-86.
Myomo Specific Research Overview
Myomo® has been an active part of several clinical research studies since being incorporated in 2004. We partner with the leading experts in rehabilitation to make sure that the most comprehensive clinical studies are completed. Our studies are focused on providing a tool that supports the evidence based practice model of therapy delivery.
The technology has been clinically tested with scientific partners that are experts in stroke upper extremity rehabilitation. Their partnership along with the help of over 50 stroke subjects has allowed us to come up with clinical protocols and guidelines that work for both acute and chronic patients. These guidelines are given to our certified therapists during our CE accredited training for PTs and OTs.
InREACH Study [ 1 ]
In December 2010, a randomized control study of 30 subjects was completed. The goal of the study has been to compare therapy with Myomo to standard treatment. Currently, thirty chronic stroke survivors are receiving six weeks of therapy three times per week for one hour. The treatment sessions focus on three outcome measures that have been proven to be valid and reliable in the literature. The outcome measures include the Fugl Meyer ( Impairment Measure ), COPM ( Functional Measure) and the SF36 ( Quality of Life Measure ). Additionally, kinematic data is being collected. The initial outcome measures have been very promising, with patient improvement seen in all areas. Publication of the first data set is pending.
A case study from this research titled "Neurorobotics for the Severely Affected Arm in Chronic Stroke" was published in The Journal of Neurologic Pysical Therapy in March 2011. As cited in the article, after completing an evidence-based treatment program using Myomo, the subject exhibited reduced affected arm impairment (+2 points on the FM), increased ability to perform valued activities, increased satisfaction with performance of these activities (indicated by score increases of +2 and +1.8 points on the COPM Performance and Satisfaction scales, respectively), improved strength, performance of activities of daily living, hand function, participation, and physical function (as indicated by increases in respective SIS scores). To acquire the full case study, click here.
Contact: Enrollment in this study has been completed.
Functional Reach Study [ 2 ]
Scott Bleakley, a doctoral candidate in the Department of Occupational Therapy at University of Pittsburgh, has commenced a study examining the effects of the Myomo Neuro-robotic System on the recovery of reaching performance after stroke. Mr. Bleakley, who is currently the Director of Physical Therapy at HealthSouth Sewickley Rehabilitation Hospital, was first introduced to the Myomo orthosis in his clinical practice at HealthSouth Harmarville Hospital. His clinical experiences with the device gave rise to his dissertation study at the University of Pittsburgh.
NIH funded Study [ 3 ]
Dr. Stephen Page at the University of CIncinnatti received national funding to continue his research using the Myomo technology. He is the first researcher to test the now the lighter and smarter mPower 1000 on chronic stroke survivors. The study will progress patients from simple movements to everyday functional activities using the new technology's simplified interface and enhanced design. The study starts in early 2011 and will run until 2012.
Interested participants should contact Dr. Page directly at the following email: firstname.lastname@example.org
1 - Dr. Stephen Page at the University of Cincinnati, Drake
2 - Scott Bleakely and Dr. Elizabeth Skidmore at the University of Pittsburgh
3 - Dr. Stephen Page at the University of Cincinnati, Drake
The American Journal of Physical Medicine & Rehabilitation published in April 2007 the results of a clinical study with MIT and Spaulding Rehabilitation Center using the Myomo Neuro-robotic System with severe chronic stroke patients (1.5-to-10-years post CVA) with upper extremity hemiparesis. (Stein J., Narendran K., McBean J., Krebs K., Hughes, R. Electromyography-Controlled Exoskeletal Upper-Limb-Powered Orthosis for Exercise Training after Stroke. Am. J. Phys. Med. Rehabil. Vol. 86. No. 4. 2007).
Based on these results, clinical experts have suggested that the Myomo device may serve as a Therapy Gateway for severe chronic patients who are so impaired that they currently are ineligible for other upper extremity stroke treatments.