Transcript M5 - Tetra Hand 2013

Natasha van Zyl MBChB, FRACS
Plastic and Reconstructive Surgeon
The Upper Limb Program
Victorian Spinal Cord Service
Austin Health
Heidelberg, Victoria, Australia
Co-Authors:
Stephen Flood
Michael Weymouth
Catherine Cooper
Jodie Hahn
Andrew Nunn
To reconstruct: Elbow extension
 Grasp
 Release
To do it: By using nerve transfers alone
 With no/little morbidity from donor nerve harvest
 While keeping the all the options for standard
tendon transfer reconstruction available
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Background to the conception of this project
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Therapeutic & investigational techniques involved
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Logistics of delivery & assessment of safe nerve
transfer reconstruction in tetraplegia
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Inspiration: Success of nerve transfers in BPI & PNI
Reanimate the native muscle directly
Careful choice of donor nerves can preserve
muscles used for tendon transfers
These muscles can be used to reconstruct distal
functions e.g. opposition, intrinsic function
No more grafts, tendon tensioning, stretching or
adhesion problems, no long immobilisations
Greater than 1:1 functional exchange
Surgical reinnervation of a denervated muscle by transferring an
expendable, intact donor nerve to the non-functional nerve of a
paralysed muscle in order to reanimate that muscle with axonal
ingrowth from the donor nerve
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Donor nerves
Use “obscure” muscles – difficult to be sure
they are under voluntary control
Recipient nerves
May be LMN or UMN denervated or a
combination of both so time to surgery is an
issue
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3 Surgeons
2 Specialist Tetraplegia OT’s
Spinal Rehabilitation Physicians
Spinal Physiotherapists and OT’s
Neurologist
Neuroscience technician
(Histopathologist)
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SCI Adults, C5-C7 motor level of injury
Complete or incomplete
Seeking surgical improvement of upper limb
function
No head, BPI or PNI
No pre-existing neurological condition
Able to comply with therapy pre and post op
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Initial consult - 3/12
Routine motor and sensory examination
Upper limb AROM and PROM
Upper limb spasticity assessment
Examination of all potential donor nerve muscles
FES of recipient nerve’s muscles
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Details of operation
Hospital stay
Immobilisation and upper limb therapy
Time till first reinnervation expected
Full maturity may take up to 12-18m
Expected outcomes nerve vs tendon transfer
Specific risks: motor or sensory disturbance,
failure of transfer
Opportunity to meet previous patients
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Measurement of pinch and grip strength
Modified pinch meter by Jaymar which allows testing of
weak/little strength
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Action Research Arm Test
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Grasp Release Test
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A timed test of lateral pinch and grasp which records how many
objects can be picked up and released in a given time
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Canadian Occupational Performance Measure
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Spinal Cord Independence Measure
Donor Muscles
 Are they under voluntary control?
 Is there evidence of any denervation?
Recipient muscles
 Are they UMN or LMN denervated?
 Or a combination of both?
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Microscope/microsurgery instruments
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Nerve stimulator -Biphasic nerve/muscle stimulator with a range
of stimulation control (Checkpoint® Stimulator/Locator, Cleveland, OH, USA)
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Intraoperative Motor Evoked Potentials -Using
trained multi pulse trans-cranial electrical stimulation of the motor cortex
Elbow Extension
 Teres Minor  Triceps Nerve(s)
(Bertelli, J. A., et al. (2011) J Neurosurg 114(5): 1457-1460)
Grasp
 Brachialis  Anterior Interosseous Nerve
(Gu, Y., et al. (2004). Microsurgery 24(5): 358-362)
Release
 Supinator  Posterior Interosseous Nerve
(Bertelli, J. A., et al. (2010). J Hand Surg Am 35(10): 1647-1651)
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Hospital stay 48hrs
Plaster changed to thermoplastic forearm
splint and broad-arm sling
Outpatient hand therapy begins immediately
Surgical review 3 monthly for first year, then
6 monthly for second year
Outcome assessments at 12,18 and 24m
Phase 1
 Protect the transfer
Phase 2
 Activate donor & watch for flicker in recipient
muscle
Phase 3
 Strengthen recipient muscle
Phase 4
 Disassociate donor from recipient
Relatively easy to expand the team & services
needed
 Learning curve:
– Patient selection
- Surgical techniques and timing of surgery
- Utility of NCS/EMG and MEPs
 Development of protocols including:
- Pre op clinical evaluation
- Intra op data collection
- Post op nerve transfer therapy
- Timing of post op reviews/outcome assessments
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