Targeted Muscle Reinnervation: Occupational Therapy - Rehabilitation Institute of Chicago

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Targeted Muscle Reinnervation: A Neural Interface for Artificial Limbs

Targeted Muscle Reinnervation: A Neural Interface for Artificial Limbs (CRC Press, 2013) can be purchased at the CRC Press website or on Amazon.

RIC Center for Bionic Medicine

TMR research was pioneered at the Center for Bionic Medicine (CBM). The CBM combines science, engineering, and clinical skill to improve function and life quality for persons with limb loss.

Development of this website was supported by the National Library of Medicine of the National Institutes of Health, Award Number G13LM011221. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Occupational Therapy for the Targeted Muscle Reinnervation Patient

Occupational Therapy

Principles of Occupational Therapy

Effective occupational therapy after TMR surgery ensures that patients gain intuitive control of their prostheses and receive the full benefits of TMR. During pre-operative and post-operative training sessions, therapists must consider issues unique to TMR patients and plan accordingly. Following fat removal and soft tissue revision during TMR surgery, the size and shape of a patient’s residual limb may be altered, resulting in the need for socket modification or replacement. Any alteration of control methods, socket or electrode locations will require the OT to train the patient in using the prosthesis as intended. Knowledge of the location of each brachial plexus nerve transfer and the functions of each nerve is therefore essential for developing optimal control strategies.

Read about the treatment phases below to learn more, though the overall time schedule varies on the needs and progression of each specific patient.


Thoroughly discuss with the patient expectations and the post-operative program. Provide them with written and visual information.

Immediately after Surgery

All initial efforts after surgery should be focused on wound healing and controlling any surgical pain. Usually, it takes about 2–3 weeks for the surgical incision to heal and for the soft tissues to consolidate.

3–4 Weeks after Surgery

After the surgical incisions have healed, patients should begin an “exercise” program to strengthen relevant muscles for myoelectric prosthesis control. Individuals can first begin with mental practice—the repetitive motor imagery of a given movement. This mental practice generates changes in brain activation [1,2], improves motor performance [3], and can increase muscular force [4] without direct muscle activation [3, 5]. Individuals should attempt to move each segment of the missing limb (fingertips, fingers, wrist, etc.) several times daily. They can do this by thinking about past activities they performed with their hands or arms, such as buttoning a shirt, making a sandwich, or playing an instrument. Initially there will be no visible response to this effort, as reinnervation has not yet occurred.

6–15 Weeks after Surgery

RIC Occupational TherapyExamples of gross motor patterns flexions (median and
ulnar nerves, top) and extension (radial and ulnar nerves,
bottom). (Click image to enlarge)

When specific muscle twitching occurs in response to efforts to move limb segments, patients should begin practicing gross motor movement patterns. The objective is to strengthen the targeted muscles by having the patient perform gross movement patterns using maximal contractions. Patterns that incorporate the distribution of the nerve transfers should be used, and movements should be performed bilaterally to further promote motor recruitment. Strengthening is achieved by progressively increasing the force and duration of muscle contractions, so exercise sets should be repeated at least four times per day. Early in training, the reinnervated muscle will still be weak and temporarily paralyzed, so muscles may tire quickly and patients will need to take frequent rest breaks.

The elbow should be excluded from all patterned exercises, as the coupling of elbow-flexion with hand-close, and elbow extension with hand-open can prevent successful TMR prosthetic fitting.

10–20 Weeks after Surgery

When consistent muscle target activation is palpable by the occupational therapist during gross movement exercises, patients should begin discrete movement strengthening. With discrete actions, the goal is to develop central actions that are strong, independent and isolated in preparation for fitting the new targeted reinnervation-control prosthesis. A discrete exercises program guide (PDF) can be downloaded here.

24+ Weeks after Surgery

When myo-testing indicates three or more potential independent isolated myoelectric sites, prosthesis control training can begin. In particular, muscle relaxation techniques, which help patients avoid overexertion and fatigue, allow EMG signals to fall below a certain threshold so they can be used as an “off” signal.

Assessments and Education before Surgery

Before TMR surgery, physiatrists and OTs should particularly note a patient’s proximal shoulder on the injured side, as other joint injuries commonly coincide with traumatic arm amputations. Additionally, they should focus on a patient’s posture and core condition, which can affect prosthesis control, and:

  • Make sure patients are strong and capable as possible using their current prosthesis.
  • Assist patients in understanding the TMR concept.
  • Prepare patients for the healing and recovery process, and foster realistic expectations and goals.
  • Educate patients on techniques needed for increasing independence in basic self-care without a prosthesis.

In order to develop a unique occupational therapy plan, several outcome measures should be used to document changes in patients’ abilities to control prostheses, including the Canadian Occupational Performance Measure (COPM) and Patient Specific Functional Scale (PSFS).

Quantitative Outcome Measures

Qualitative Outcome Measures

Southampton Hand Assessment Procedure (SHAP)

Orthotics & Prosthetics User-Survey-Upper Extremity Functional Status (OPUS-UEFS)

Assessment of Capacity for Myoelectric Control (ACMC)

Trinity Amputation & Prosthetics Experience Scales (TAPES)

UNB Test of Prosthetics Function

Canadian Occupational Performance Measure (COPM)

Box & Block Test

Disabilities of the Arm, Shoulder & Hand Outcome Measure (DASH)

Jebsen Taylor Hand Function Test

Patient Specific Functional Scale (PSFS)

Diagnostic Fitting and Four-Site Training

Patients should first begin EMG testing of attempted movements with a single degree of freedom (DoF), such as elbow flexion/extension. The goal is to identify a physiologically relevant movement that provides the strongest, most independent EMG signals.

Once the patient has mastered control of each degree of freedom, OTs should help patients achieve separate control of multiple degrees of freedom. During this time, patients and OTs should first focus on increasing the speed of movement drills and then on using the prosthesis to perform various tasks. The goals are to:

  1. Verify electrode locations and allow for alternative site exploration if necessary, and for the patient to demonstrate clearly differential flexion and extension signals. Patients must get used to the weight of the prosthesis and the movements of its components.
  2. Achieve isolated, independent movement of each DoF to achieve separate control of both DoFs.
  3. Train the patient to quickly and easily move from one function to another.
  4. Operate additional prosthetic components and alternative component options.


  1. Lafleur MF, Jackson PL, Malouin F, Richards CL, Evans AC, Doyon J. Motor learning produces parallel dynamic functional changes during the execution and imagination of sequential foot movements. NeuroImage. May 2002;16(1):142-157.
  2. Jackson PL, Lafleur MF, Malouin F, Richards CL, Doyon J. Functional cerebral reorganization following motor sequence learning through mental practice with motor imagery. NeuroImage. Oct 2003;20(2):1171-1180.
  3. Yue G, Cole KJ. Strength increases from the motor program: comparison of training with maximal voluntary and imagined muscle contractions. Journal of neurophysiology. May 1992;67(5):1114-1123.
  4. Cornwall MW, Bruscato MP, Barry S. Effect of mental practice on isometric muscular strength. The Journal of orthopaedic and sports physical therapy. 1991;13(5):231-234.
  5. Ranganathan VK, Siemionow V, Liu JZ, Sahgal V, Yue GH. From mental power to muscle power--gaining strength by using the mind. Neuropsychologia. 2004;42(7):944-956.


Kathy A. Stubblefield

Kathy A. Stubblefield, OT, received a BS degree in occupational therapy from the University of Kansas. Ms. Stubblefield worked as a Research Therapist for the Center for Bionic Medicine at the Rehabilitation Institute of Chicago until her retirement in May 2012. She has more than 35 years of experience and expertise in the treatment of patients with stroke, spinal cord injury, and upper limb amputation. In addition, Ms. Stubblefield has participated in research, training, and testing of TMR patients using conventional and experimental prosthetic components and control schemes.

Todd A. Kuiken, MD, PhDTodd A. Kuiken, MD, PhD, leads an interdisciplinary team that includes physicians, prosthetists, therapists, neuroscientists, engineers, software developers, graduate students, and post-doctoral researchers at the Center for Bionic Medicine within the Rehabilitation Institute of Chicago.

Dr. Kuiken received a BS in biomedical engineering from Duke University, and a PhD in biomedical engineering and an MD from Northwestern University. He completed a residency in physical medicine and rehabilitation at the Rehabilitation Institute of Chicago and Northwestern University Medical School. In addition to leading the Center for Bionic Medicine, Dr. Kuiken is Director of Amputee Services at the Rehabilitation Institute of Chicago. He is also a Professor in the Departments of Physical Medicine and Rehabilitation, Surgery, and Biomedical Engineering at Northwestern University. Dr. Kuiken is the recipient of many awards and honors for his work on TMR and is an internationally respected leader both in research and the clinical care of people with limb loss.

Kristi Turner, OTR/LWebsite Contributor

Kristi Turner, OTR/L, earned a BS degree in occupational therapy from Saginaw Valley State University. She works as a research therapist at the Center for Bionic Medicine and also treats patients at the Rehabilitation Institute of Chicago's Outpatient Center. She is a member of the American Academy of Orthotists and Prosthetists, the International Society for Prosthetics and Orthotics, and is a contributing faculty member at Northwestern University’s Prosthetics-Orthotics Center. She has been an occupational therapist for more than 15 years and specializes in the treatment of upper limb amputation, multiple limb amputations, and burn injury. She has been involved in research, training, and testing with both TMR and non-TMR patients using conventional and experimental prosthetic components as well as conventional and advanced control schemes.