SYM02: Jedi Mind Tricks: Targeted Muscle Reinnervation and Advanced

Prosthetics

Moderator(s): David M. Brogan, MD, MSc.

Faculty: Kyle R. Eberlin, MD, Jason H. Ko, MD, MBA, Jason M. Souza, MD, and Scott M. Tintle, MD

Session Handouts Friday, October 02, 2020

75TH VIRTUAL ANNUAL MEETING OF THE ASSH OCTOBER 1-3, 2020

822 West Washington Blvd Chicago, IL 60607 Phone: (312) 880-1900 Web: www.assh.org Email: [email protected]

All property rights in the material presented, including common-law copyright, are expressly reserved to the speaker or the ASSH. No statement or presentation made is to be regarded as dedicated to the public domain.

9/2/2020

Symposium #2: Jedi Mind Tricks: Targeted Muscle Reinnervation and Advanced Prosthetics

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Symposium Objectives

• Explain the principles of Targeted Muscle Reinnervation as well as its indications in neuroma management

• Have an appreciation of the variety of myoelectric prosthetics currently available for upper extremity amputees

• Understand the post-operative protocols and rehabilitation necessary to maximize functional results.

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Program & Faculty

• Upper Extremity Targeted Muscle Reinnervation: Basic Principles and Technique • Jason Ko, MD, MBA (Northwestern University)

• Osseointegration of Upper Extremity Prosthetics • Jason Souza, MD (Walter Reed National Military Medical Center)

• Efficacy of TMR in Reducing Neuroma & Phantom Limb Pain • Kyle Eberlin, MD (MGH / Harvard)

• Beyond Skywalker’s Hand: Current Prosthetic Options • David M. Brogan, MD, MSc (Washington University in St. Louis)

• Future Directions in TMR Research • Scott Tintle, MD (Walter Reed National Military Medical Center)

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DISCLOSURES Jason H. Ko, MD, MBA

Consulting Fee: Integra LifeSciences Corporation EDGe Surgical, Inc. Speakers Bureau: Checkpoint Surgical, Inc. Others: Mesh Suture, Inc. (Scientific Advisory Board)

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Upper Extremity Targeted Muscle Reinnervation (TMR): Basic Principles and Techniques

Jason H. Ko, MD, MBA Associate Professor Division of Plastic and Reconstructive Surgery Department of Orthopedic Surgery Northwestern University Feinberg School of Medicine Chicago, IL USA

Jedi Mind Tricks: TMR and Advanced Prosthetics ASSH Annual Meeting October 2, 2020

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WHY

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WHY WHO

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WHY WHO HOW

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1891

Courtesy of Gregory Dumanian, MD 9

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2020?

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Myoelectric prostheses

• Major limitations – Can only move one “joint” at a time – Controlled by the “wrong” muscle signals

Courtesy of Gregory Dumanian, MD

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1. NEURAL SIGNALS STILL EXIST

TARGETED MUSCLE REINNERVATION

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The brain still creates signals that go to the nerves. Can we tap into these signals to control an artificial arm?

TARGETED MUSCLE REINNERVATION

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CAN WE RECORD CONTROL SIGNALS FROM THE BRAIN??

TARGETED REINNERVATION 18

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CAN WE RECORD CONTROL SIGNALS FROM THE NERVES??

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1. NEURAL SIGNALS STILL EXIST

2. AVAILABLE MUSCLE SITES

TARGETED MUSCLE REINNERVATION

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1. NEURAL SIGNALS STILL EXIST

2. AVAILABLE MUSCLE SITES

3. INTUITIVE CONTROL

TARGETED MUSCLE REINNERVATION

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TARGETED MUSCLE REINNERVATION (TMR) COMBINES AVAILABLE TECHNOLOGY WITH MODIFICATION OF THE RESIDUAL ANATOMY

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• 54-year-old electrical utility lineman

• May 2001: suffered 7200 volt burns

• Immediate bilateral shoulder disarticulation

• Split-thickness skin grafts for closure of painful wounds First TMR Patient 24

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Gregory Dumanian, MD Todd Kuiken, MD, PhD Feinberg School of Medicine Rehabilitation Institute of Northwestern University Chicago

* Surgery performed January 2002

TMR Nerve Transfer Surgery 25

Surgical Considerations

• No plexopathy • Good pectoralis function • Tinel’s signs at anterior axillary line We know his nerves work!!! 26

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Surgical Technique

• Mobilize nerve stumps • Divide normal innervation • Create distinct segments of pectoralis muscle • Coapt nerves & muscle segments

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Surgical Technique

• Mobilize nerve stumps medial • Divide normal pectoralis major lateral innervation • Create distinct segments of pectoralis muscle • Coapt nerves & muscle segments

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Surgical Technique

• Mobilize nerve stumps medial 1 • Divide normal 4 pectoralis major 2 lateral innervation • Create distinct segments of 3 pectoralis muscle • Coapt nerves & muscle segments

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Surgical Technique

• Mobilize nerve stumps • Divide normal pectoralis major innervation • Create distinct segments of pectoralis muscle • Coapt nerves & muscle segments

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Targeted Muscle Reinnervation

Pre-Op: 1 myoneurosome Post Op: 4 myoneurosomes

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Thumb Abduction Thumb Wrist Supination Adduction

PATTERN RECOGNITION

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Elbow Flexion Elbow Extension

Hand Close Hand Open

PATTERN RECOGNITION

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Myoelectric

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Myoelectric Prosthesis

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Original Prosthesis Nerve Transfer Prosthesis (Used more than 20 months) (Used about 2 months) 39

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Targeted Muscle Reinnervation

• Left upper extremity prosthesis created with myoelectric controls

“Doc, now I don’t have to think about what I’m doing so much—I just do it.”

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Who is a candidate?

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Courtesy of Gregory Dumanian, MD

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Courtesy of Gregory Dumanian, MD

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Targeted Muscle Reinnervation (TMR) Transhumeral amputees

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Transhumeral Targeted Muscle Reinnervation A different amputation... A different surgery!

Proximal Radial n. to Triceps (no change) Elbow Down

Musculocutaneous n. to Lateral Biceps (no change) Elbow Up

Median n. to Medial Biceps Hand Close

Distal Radial n. to Brachialis Hand Open

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Transhumeral Surgical Procedure

Median nerve Medial biceps Lateral head triceps Ulnar Brachialis (if long limb)

Musculocutaneous nerve Lateral biceps Proximal radial nerve Long head triceps

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Conventional Treatment TMR Post-Op 2 signals 4 to 5 signals

Surface Electrode

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Transradial TMR

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Median, ulnar, and radial Transferred to motor nerves in neuromas forearm 1) Median to AIN 2) Ulnar to FCU 3) DSBRN to FDS

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1 week old crush injury transferred to me

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1) Median to AIN 2) Ulnar to FCU 3) DSBRN to FDS

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1) Median to AIN 2) Ulnar to FCU 3) DSBRN to FDS

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Partial Hand TMR

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Partial Hand TMR

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Epithelioid sarcoma

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2 years later… recurrence

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Partial hand TMR

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TMR nerve transfers: Digital nerves to motor branches of lumbrical muscles

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Partial hand TMR

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3 months post-op

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WHY

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WHY WHO

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WHY WHO HOW

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1891

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The future is now…

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Thank you!

[email protected]

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DISCLOSURES

Jason M. Souza, MD

Speaker has no relevant financial relationships with commercial interest to disclose.

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SYM02: Jedi Mind Tricks: Targeted Muscle Reinnervation and Advanced Prosthetics (VAM20)

Jason M. Souza MD, FACS

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The views expressed in this presentation are those of the author and do not reflect the official policy of Walter Reed National Military Medical Center, the Uniformed Services University of Health Sciences, Department of the Army, Department of the Navy, the Department of Defense or the United States Government.

Faces and Tattoos Are Shown with Permission

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Jason M. Souza MD, FACS

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a.Inclusion Criteria • The Patient must be a transhumeral amputee, age 22 -65 • The Patient with a residual ≥ 10 cm in length • Documented difficulty with prosthetic wear due to conditions including (not limited to) inadequate soft tissues, ulceration(s), socket discomfort, excessive perspiration, intolerance to interface materials, or other inadequate methods of suspension. • Cortical thickness of at least 1.5mm • Residual humerus suitable for size 13-25 fixtures by radiographic templating. • The Patient must be suitable for surgery based upon medical history and physical examination. • The Patient must be likely to comply with treatment, rehabilitation and follow- up requirements.

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a.Inclusion Criteria • The Patient must be a transhumeral amputee, age 22 -65 • The Patient with a residual humerus ≥ 10 cm in length • Documented difficulty with prosthetic wear due to conditions including (not limited to) inadequate soft tissues, ulceration(s), socket discomfort, excessive perspiration, intolerance to interface materials, or other inadequate methods of suspension. • Cortical thickness of at least 1.5mm • Residual humerus suitable for size 13-25 fixtures by radiographic templating. • The Patient must be suitable for surgery based upon medical history and physical examination. • The Patient must be likely to comply with treatment, rehabilitation and follow-up requirements.

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Artificial Limb

Osseointegrated Human-Machine Muscular Gateway Interface (OHMG)

Neural Interface

Artificial Limb Controller Bio-amplifiers & PatRec

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The DoD Osseointegration Program Team

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THANK YOU

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DISCLOSURES

Kyle R. Eberlin, MD

Consulting Fees: AxoGen, Integra, Checkpoint, Tissium

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Efficacy of TMR in Reducing Neuroma and Phantom Limb Pain

Kyle R. Eberlin, MD

Assistant Professor of Surgery, Harvard Medical School Program Director, Harvard Plastic Surgery Residency Program Associate Program Director, MGH Hand Surgery Fellowship

October 2nd, 2020

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Why has TMR become popular for addressing Neuroma and Phantom Limb Pain?

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Outline • Definition and Pathophysiology of Neuroma • Diagnosis and Decision for Surgical Intervention • Surgical Options Including TMR

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Outline • Definition and Pathophysiology of Neuroma • Diagnosis and Decision for Surgical Intervention • Surgical Options Including TMR

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This problem is more common than surgeons think…

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What are Neuromas?

• Definition: disorganized growth or tumor of nerve tissue following nerve injury • Occurs when a nerve ending is “not connected” to its target organ

• Neuroma vs. symptomatic neuroma • Classified as stump (“end”) neuroma or neuroma in continuity

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Origin Target

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Origin Target

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Origin Target

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Origin Target

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Neuroma Pathophysiology • Does not require nerve transection (!) • May occur following poorly performed neurorrhaphy • i.e. fasicular overlap, undue tension, axonal escape • Cause pain through central and peripheral mechanisms1 • Peripherally mediated pain through axonal irritation • Centrally mediated pain through development of spontaneous activity within dorsal root ganglion and CNS

1. Birch R. The peripheral neuroma. In: Green DP, Hotchkiss RN, Pederson WC, Wolfe S. Green’s operative hand surgery. 5th ed. New York: Churchill Livingstone, 2005:1102–1111. 128

Outline • Definition and Pathophysiology of Neuroma • Diagnosis and Decision for Surgical Intervention • Surgical Options Including TMR

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How does one diagnose a symptomatic neuroma?

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Diagnosis of Symptomatic Neuroma

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Decision for Intervention

• Decision making sometimes easy, sometimes difficult • Obvious stump neuromas are relatively easy to diagnose, decision making can be straight-forward • Neuroma in continuity much more difficult – depends on symptoms and degree of preserved function • How symptomatic is the patient?

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Outline • Definition and Pathophysiology of Neuroma • Diagnosis and Decision for Surgical Intervention • Surgical Options Including TMR

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Categorization of Surgical Interventions for Neuroma Paradigm Shift

Passive/Ablative Active/Reconstructive

• Excision only or traction • Hollow tube reconstruction neurectomy • Allograft or autograft reconstruction • Excision and implantation (muscle, bone) • “End-to-side” neurorrhaphy • Centro-central connector • TMR assisted neurorrhaphy • RPNI

• Nerve Cap Eberlin KR, Ducic I. Surgical Interventions for Pain Management: A Changing Treatment Paradigm. • Relocation Nerve Grafting PRS-GO

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Surgical Options for Stump Neuroma

Eberlin KR, Ducic I. Surgical Interventions for Pain Management: A Changing Treatment Paradigm. PRS-GO

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Surgical Options for Stump Neuroma

Eberlin KR, Ducic I. Surgical Interventions for Pain Management: A Changing Treatment Paradigm. PRS-GO

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Question 1: Is TMR efficacious in patients with established neuropathic pain following amputation?

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DELAYED TMR

N=14 N=14

Reduction in phantom limb pain scores at one year was significantly greater in the TMR group compared to standard treatment. Change scores for residual limb pain were favorable for TMR.

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RCT Results: Buried in Muscle Failures with Crossover to TMR RESIDUAL LIMB PAIN

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RCT Results: Buried in Muscle Failures with Crossover to TMR PHANTOM LIMB PAIN

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Question 2: Is TMR efficacious acutely, at the time of amputation?

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Age (Mean, SD) 48.2 (16) Male 30 (58.8%) Reason for amputation Cancer 20 (39.2%) Infection 5 (9.8%) Ischemia 2 (3.9%) Trauma 16 (31.4%) Other 8 (15.7%)

Level of amputation ACUTE TMR Above elbow 4 (7.8%) 18 (35.3%) Above/ through knee N=51 TMR within 14 days Below elbow 4 (7.8%) Below knee 18 (35.3%) Shoulder 7 (13.7%) disarticulation 146

Immediate TMR significantly reduces NRS pain scores * Inverse probability of treatment (IPTW) weighting to balance demographics and amputation details

TMR General Outcom Median Median p- e (IQR*) (IQR*) value Phantom Limb Pain Worst 1 (0-5) 5 (1-7) 0.003 pain Best <0.001 0 (0-0) 0 (0-3) pain Current <0.001 0 (0-1) 1 (0-4) Pain

Residual Limb Pain Worst 1 (0-3) 4 (1-7) <0.001 pain Best 0 (0-0) 1 (0-3) <0.001 pain Current 0 (0-0) 2 (0-4) <0.001 Pain 147

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Immediate TMR significantly reduces PROMIS pain scores

* Inverse probability of treatment (IPTW) weighting to balance demographics and amputation details TMR General Median Median Outcome (IQR*) (IQR*) p-value Phantom Limb Pain Intensity 36.3 (31-40)48.4 (41-54) <0.001

Behavior 50.1 (37-52)56.6 (51-61) <0.001

Interference 40.7 (41-41)55.8 (41-63) <0.001

Residual Limb Pain Intensity 30.7 (31-36)46.8 (41-52) <0.001

Behavior 36.7 (37-50)57.3 (52-61) <0.001

Interference 40.7 (41-41)57.3 (41-64) <0.001

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Figure 1. Narcotic Use Before and After Amputation with Targeted Muscle Reinnervation 100% 90% 80% None 70% 60% Infrequent 50% Acute 40% 30% Acute on Chronic Percent of Patients of Percent 20% Chronic 10% 0%

Follow-up 149

PROMIS

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Conclusions • Symptomatic neuromas are more common than you think (!)

• There are many available techniques for the surgical treatment of symptomatic neuroma, and one should consider TMR

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Thank You [email protected]

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DISCLOSURES

David M. Brogan, MD, MSc.

Contracted Research: Depuy - Synthes

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Symposium #2 Beyond Luke Skywalker’s Hand: Current Prosthetic Options David M. Brogan, MD, MSc

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Disclosures

• Research Support from Depuy / Synthes • Royalties from Springer

• Thanks to Jon Wilson, CPO, LPO for contribution of some slides

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Objectives

• Understand the types of prosthetics available

• Describe the major components of a prosthetic

• Discuss the incorporation of Targeted Muscle Reinnervation to prosthetic design and function

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CAUSES OF UPPER EXTREMITY AMPUTATION 2 3 20 2% Cancer 3% Congenital 20% Vascular Disease Diabetes & PVD 7575% Trauma

Approximately 40,000 Americans lose a limb annually and approximately 30% of those lose a hand or arm.

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Amputation Levels

• Partial Fingers • Partial Hand • Wrist Disarticulation • Trans-radial (Below Elbow) • Elbow Disarticulation • Trans-humeral (Above Elbow) • Shoulder Disarticulation • Forequarter (Interscapular Thoracic)

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Washington University Orthopedics | Barnes Jewish Hospital Level of Amputation Informs Functional Needs

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Early Prosthetic Intervention Process

Keys to successful outcomes • Early prosthetic intervention • Experienced team approach • Prosthetic training • Patient education • Patient monitoring and follow-up

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Main Post-op Goals for fitting Upper Limb Amputees

• Allow patient to be able to feed themselves • Promote healing (minimizing edema) • Gain and Maintain ROM • Prevent limb complications • -limb contractures • -adherent scars • Promote Self-care and Preserve self- image • Scar massage once completely healed

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Rehabilitation Timeline

PREVENTION IMPRESSION CONDITIONING 8-12 Weeks 3 Weeks 2 Weeks and beyond

Healing. Incision line Custom cast of Work with an OT/PT is FULLY healed, and limb is taken, fit is to learn swelling is stable, the confirmed and how to use UE Pros fitting process final device taken Inpatient or begins! home. ~3 total Outpatient Setting Sutures Removed (3-5 weeks) visits. Edema Reduced

Approximately 3-6 Months

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Initial Care

Post-op compression therapy utilizing a Upper extremity Juzo, compresso grip and Silicone Sleeves, Desensitizing Techniques

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Types of Prosthetics

Passive Body Powered Hybrid Myoelectric Functional Conventional Controlled Cosmetic External Power

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Passive Cosmetic

• Advantages • Lightweight • Cosmetic • Less Harnessing • Simple • Little maintenance • Great for partial hands • Provides Opposition

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Passive Cosmetic

Disadvantages • Limited active prehension • Limited function • Decreased durability • Unrealistic expectations of cosmesis • Custom silicone very expensive (not covered by Medicare)

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Right Shoulder Disarticulation Passive Cosmetic Prosthesis

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Body Powered

• Components on the prosthesis, such as the elbow and terminal device are operated by a harness system. The harness system is controlled by the gross body movements ( bi- scapular abduction, glenohumeral flexion, chest expansion, shoulder depression, extension.

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Body Powered

Advantages • Heavy duty construction • Proprioception • Less Expensive • Lighter in weight • Reduced cost • Low maintenance

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Body Powered

Disadvantages • Grip Force can be limited (shoulder strength and number of rubber bands) • Functional Envelope (ROM) is limited • Harness can be uncomfortable and restrictive • Poor cosmesis • Possible Over-use, peripheral neuropathies

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Prosthetic Components

• Terminal Device • Suspension System • Mechanical / Electrical Interface

For Myoelectric prosthetics, components include various control options: • Single or dual electrode sites • Pro control switch – rocker, pull, push, Touch pad • Pattern Recognition Software • Gesture technology=Gyroscopic technology

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Terminal Devices

• Voluntary Opening • Pinch force is determined by the number of rubber bands or springs (1RB=1-1.5#) • Varity of sizes and shapes

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Terminal Devices

• Voluntary Closing • Pinch force determined by strength of wearer. • Average adult can generate 40-60lbs of pinch force

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Special Use Prosthesis for Upper Extremity

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Designing a Sports Prosthesis

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Custom Seal Hypobaric System

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Harnessing for Body Power Triple Control Harness -Three independent motions allow Activation of the terminal device, Elbow joint lock/release, Forearm flexion

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Myoelectric Prosthetics

Advantages • Grip force is independent of the patient’s strength and ROM • Limited Harnessing • Less energy consuming • More accurate control over TD • More cosmetic than Body Powered

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Myoelectric Prosthetics

Disadvantages • Increased cost and maintenance • Increased weight • Charging Battery • Environmental interference • Weight limitations?

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CoAPT/Infinity/Ottobock Pattern Recognition

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Co-APT MyoTesting Interscapular Thoracic

9-16 Domed Shaped Electrodes

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Case 1: JW Myoelectric Partial Hand Prosthesis

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38 yo M s/p industrial log splitting accident

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Immediate Post-Op

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1st Diagnostic fitting

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Pre-programmed positions

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Washington University Orthopedics | Barnes Jewish Hospital Case #2 - BM

• 42 yo M involved in MCC with mangling injury of R forearm • Underwent initial revascularization by on call hand team • Ultimately, degree of injury was too severe, patient elected for trans-radial forearm amputation • Goals of TMR: • Prevent / minimize neuroma pain • Maximize potential for myoelectric prosthetic

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First Generation Prosthetic (Mechanical)

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2nd Generation Prosthetic (myoelectric)

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3rd Generation Prosthetic (Myoelectric)

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Transhumeral Amputation

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Take Home Points

• The end goal should guide the early surgeries • Satisfactory fitting of a prosthetic requires a stable soft tissue envelope • TMR has potential to expand the capacity of myoelectric prosthetics • Myoelectric prosthetics continue to improve with regards to residual limb fixation, neural signal interface, control mechanisms and terminal components

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Thank You

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Washington University Orthopedics | Barnes Jewish Hospital

David Brogan, MD, MSc Assistant Professor Campus Box 8233 425 S. Euclid Ave. St. Louis, MO 63110 (314) 747-2813

[email protected] Washington University Orthopedics

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Scott M. Tintle, MD

Speaker has no relevant financial relationships with commercial interest to disclose.

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TARGETED MUSCLE REINNERVATION: FUTURE DIRECTIONS IN RESEARCH

Scott M. Tintle MD CDR, MC, USN Chief of Hand Surgery Fellowship Director Walter Reed National Military Medical Center

Associate Professor Uniformed Services University

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MANDATORY DISCLAIMER

The views expressed in this presentation are those of the authors and do not necessarily reflect the official policy or position of Walter Reed National Military Medical Center, the Department of the Navy, Department of the Army, Department of Defense, nor the U.S. Government

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WITH THANKS TO THE FOLLOWING PEOPLE

• COL Kyle Potter • LCDR Jason Souza • CAPT George Nanos

• Dr Todd Kuiken • Dr. Gregory Dumanian

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• What do we know about TMR – Improves function – Decreases pain – Creates more normal nerve anatomy

• What do we need to know about TMR? – How does it work ? – Is it warranted in every amputation?

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WHAT IS TMR?

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FUNCTIONAL IMPROVEMENT

• Simultaneous control of a two degree of freedom experimental prosthesis

• Doubling of Box and Blocks test

• 26% increase in speed of clothes pin moving test

• Subjectively pt liked it more, it was easier, faster, and felt more natural

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• Return to prior 1 Month with TMR prosthesis prosthetic use after initial post-operative recovery

• Predictable reinnervation in 5-6 month

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• “Moreover, they suggest that TMSR may counteradt maladaptive cortical plasticity found after limb Loss, in M1, Partially in S1, and in their mutual connectivity.”

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PAIN CONTROL MY NUMBER 1 REASON

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PAINFUL NEUROMA AND TMR

Effects of Targeted Reinnervation (TR) on Neuroma Pain. No. of Pre-TR Post-TR Amputation level Patients neuroma pain neuroma pain Transhumeral 18 10 1 Shoulder disarticulation 10 5 0 Total (%) 28 15 (54%) 1 (3.5%)

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Conclusions: In this first surgical RCT for the treatment of postamputation pain in major limb amputees, TMR improved PLP and trended toward improved residual limb pain compared with conventional neurectomy.

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Preemptive surgical intervention of amputated nerves with TMR at the time of limb loss should be strongly considered to reduce pathologic phantom limb pain and symptomatic neuroma-related residual limb pain. (J Am Coll Surg 2019;228:217e226. ! 2019)

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DOES EVERY AMPUTATION NEED TMR?

• Neuromas – 2nd most common reason

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100 UE AMPUTATIONS

Complication Data Complication Data Percent of amputations Total Number of patients 42 Heterotopic Ossification 19% with complications Excision Wound infection 13% Neuroma Excision 9% Wound dehiscence 6%

Total Number of 56 Scar Revision 5% Complications Contracture Release 4%

Total number of surgeries 103

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300 LOWER EXTREMITY AMPUTATIONS

Complication Data Complication Data Percent of amputations Heterotopic Ossification 24% Excision Total Number of 156 (53%) Wound infection 27% patients with complications Neuroma Excision 11% Wound dehiscence 4% Scar Revision 8% Total Number of 261 Myodesis Revision 6% Complications

Total number of 465 surgeries

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(Ann Plast Surg. 38: 563, 1997.) 1997 (Br. J Plast Surg. 50: 194, 1997.) 236

2008 237

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MORE BASIC SCIENCE

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MORE BASIC SCIENCE

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SEGMENTAL INNERVATION

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Normal Neuroma After TMR nerve

Cross section of a rabbit single median nerve before transection (left), 6 weeks after neuroma formation (center), and 10 weeks post-TMR (right). Peter Kim et al, JBP&PNI, 2010

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Phantom data

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WHAT IS NEEDED?

• Large numbers- prospective, randomized trial • RPNI versus TMR in acute amputations

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THANK YOU

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