sym19: scapholunate reconstruction 2020: addressing the

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SYM19: Scapholunate Reconstruction

2020: Addressing the Critical Ligaments

Moderator(s): Scott W. Wolfe, MD

Faculty: Greg Bennett Couzens, MD, Mark Ross, FRACS, Michael J. Sandow, BMBS,

FRACS, FAOrthA, and Abhijeet L. Wahegaonkar, MD

Session Handouts

Saturday, October 03, 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]

http://www.assh.org/

mailto:[email protected]

8/31/2020

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SYM19: Scapholunate Reconstruction

2020: Addressing the Critical

LigamentsSession Chair: Scott W. Wolfe, MD

Faculty: Abhijeet L. Wahegaonkar, MD, Greg Bennett Couzens, MD, Mark Ross, FRACS and Michael J. Sandow, BMBS, FRACS, FAOrthA

SYM19: Scapholunate Reconstruction 2020: Addressing the Critical Ligaments

www.thehandsurgeryclinics.com

75th Annual Meeting of the ASSH

October 1-3, 2020

Abhijeet L. WahegaonkarAdjunct Professor of Hand Surgery

Distinguished Clinical Tutor of Orthopedic Surgery

Director- Upper Limb, Hand & Microsurgery Fellowship Program

Consultant & Head

Department of Upper Extremity, Hand & Microvascular Reconstructive Surgery

Sancheti Institute for Orthopaedics & Rehabilitation

Jehangir Hospital

Pune, INDIA

A Global Perspective on Outcomes of Scapholunate

Ligament Reconstruction

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COI/ Disclosures

• No disclosures

Scapholunate Dissociation

• Most commonly recognized pattern of carpal instability



• known predisposition for development of DJD

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• Known predisposition for development of DJD

• Thorough understanding of anatomy and mechanics is

prerequisite for appropriate management and optimum

outcomes

Treatment

• Depends on classification

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Treatment

Duration

• Acute: Good healing potential

• Subacute: Some healing potential

• Chronic: Little healing potential;

repair/reconstruction needed

• Chronic with DJD:

Reconstruction/salvage

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Treatment


• Depends on surgeons preference*

•

• *Zarkadas PC et al. A survey of the surgical management of acute and chronic scapholunate instability. J Hand Surg Am. 2004;29(5):848-857

Treatment


• Depends on surgeon’s preference/training/experience*

• Depends on patient needs and expectation

• Treatment of SLD is difficult, not always predictable, and seldom entirely satisfactory.

*Zarkadas PC et al. A survey of the surgical management of acute and chronic scapholunate instability. J Hand Surg Am. 2004;29(5):848-857.

Considerations

• 1) Is the dorsal SLL intact?

• 2) Does the dorsal SLL have sufficient tissue to be repaired?

• 3) Is the scaphoid posture normal?

• 4) Is any carpal malalignment reducible?

• 5) Is the cartilage on the radiocarpal and mid-carpal surfaces normal?

• 6) Does the abnormal SL relationship involve two distinct planes of deformity

(widening and rotatory)?Garcia-Elias M, et al Three-ligament tenodesis for the treatment of scapholunate dissociation: indications and

surgical technique.J Hand Surg Am. 2006 Jan; 31(1):125-34.

• Kitay A, Wolfe SW Scapholunate instability: current concepts in diagnosis and management. J Hand Surg Am.

2012 Oct; 37(10):2175-96.

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Considerations

How does the Classification help in Decision Making?

Garcia-Elias et al. JHS 2006



Dynamic

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Static

Stage 4: Complete SL ligament injury- nonrepairable with

easily reducible rotary subluxation of the scaphoid and

normal cartilage



normal cartilage

• Tenodesis Procedures

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normal cartilage




normal cartilage



IRReducible rotary subluxation of the scaphoid and normal

cartilage

Options

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Ligament Reconstruction Techniques

Martin Langer MD


Martin Langer MD


Martin Langer MD

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Martin Langer MD


Martin Langer MD


Martin Langer MD

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Martin Langer MD


Martin Langer MD


Modifications:Sanj KakarGabor Szalay

www.Arthrex.com

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Outcomes

Long term – recurrence

(Megerle K, et al. Long-term results of dorsal intercarpal ligament capsulodesis for

the treatment of chronic scapholunate instability. J Bone Joint Surg [Br] 2012;94-

B:1660-1665.)

Loss of arc of motion

Kinematics/ kinetics not restored

Outcomes

Wang P, et al Equivalent Clinical Outcomes Following Favored Treatments of Chronic Scapholunate Ligament Tear. HSS J. 2017;13(2):186-193.

Outcomes


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Outcomes


• No significant difference in outcomes from capsulodesis or reconstruction for treatment of chronic scapholunate instability.

• However, the retrospective studies examined were notably heterogeneous in design with high estimates of variance. Further prospective trials are necessary to determine an ideal treatment strategy.

Outcomes

Outcomes

Montgomery SJ, et al: Surgical outcomes of chronic isolated scapholunate interosseous ligament injuries: a systematic review of 805 wrists, 2019 Mar 22]. Can J Surg. 2019;62(3):1-12.

• Analysis of clinical, radiographic and patient-reported outcomes

• Used a fixed effects model weighted by sample size with combined outcomes estimated via least squares means with 95% confidence intervals

• Performed a subgroup analysis of static versus dynamic instability.

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Outcomes


• No statistically significant differences in outcomes between surgical techniques or in subgroup analysis

• Overall, postoperative wrist flexion and pain scores decreased, and grip strength and patient-rated outcomes improved.

Outcomes


Outcomes


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Outcomes


• Based on the current standard of literature, it will be difficult to advance our knowledge on chronic isolated SLIL tears. It is time to stop putting our energy into single surgeon retrospective case series.

• Collaboration in the form of multicentre prospective RCT and consistent reporting using common data elements offer an opportunity to truly understand the problem, learn about the natural history and potentially flesh out optimal treatment strategies.

Dilemma

What is the solution for treating a scapholunate dissociation that has a

static deformity and/or unusable ligament and still maintain the greatest

range of motion, preserve near normal kinematics and last?

Summary

• Proper patient selection and indication

• Multicentre prospective RCT

• Accurate detailed documentation of all patients (non-op and op)

• documentation of diagnostic method

• Stratification of patients by degree of injury

• Standardized outcome measures including patient-reported outcomes

• Long-term follow-up.

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Question

The concept that a scapholunate ligament injury

visualized arthroscopically, without static x-ray

changes, inevitably leads to SLAC wrist is supported

in the literature by what level of evidence?

A. I

B. II

C. III

D. IV

E. None

Preferred response: E

Question

The scaphoid shift test, as described by Watson, requires:

A. Ulnar-directed pressure on the scaphoid

B. Volarly-directed pressure on the scaphoid proximal pole

C. Volarly-directed pressure on the lunate

D. Dorsally-directed pressure on the lunate

E. Dorsally-directed pressure on the scaphoid distal pole

Preferred Response: E

Thank you!

www.thehandsurgeryclinics.com

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Scott W Wolfe, MD

Royalty: Trimed, Extremity Medical, ElsevierConsulting Fees: Extremity MedicalSpeakers Bureau: TriMed

None relevant to this talk

SYM19: Scapholunate Reconstruction 2020:Addressing the Critical Ligaments

SCOTT W. WOLFE, M.D.

Anatomy of the Dorsal Scapholunate Complex:Implications of Injury

Hospital for Special Surgery, New YorkWeill Medical College of Cornell University

Scott W. Wolfe, MD

© Scott W. Wolfe, MD 2020

75th Annual Meeting of the ASSH SYM19: Scapholunate Reconstruction 2020: The Critical Ligaments October 3, 2020

CapitateHamate

Triquetrum Lunate

Scaphoid

dSLT complex

The Dorsal ScapholunotriquetralLigament Complex

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THE DORSAL SLT LIGAMENT COMPLEX LIGAMENT ANATOMY

Richard A. Berger, MD, Ph.D., Hand Clinics 1997

Extension Flexion

Viegas et al., JHS 1999DRC

DIC

Dorsal SLT ligament complex

• 90 cadaveric specimens• DIC is an intrinsic ligament (carpal to carpal) • Both DIC and DRC consistently insert on lunate• DICL hypothesized to be a restraint to DISI• DRC hypothesized to be a restraint to VISI

J.Hand Surg. 1999DIC DRC

99%90%DIC

J.Wrist Surg. 2012

• Dorsal capsulo-ligamentous fold• Attaches to dorsal SLIL• Part of the complex binding DIC to SLIL• Arthroscopic repair described

J.Wrist Surg. 2014

Controversy: Dorsal Ligament Anatomy

Berger, Bishop, Bettinger 1995

Hagert, E. 2008Nagao, S. et al., 2005

Richard A. Berger, MD, Ph.D., 2003

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Controversy: Dorsal Ligament Anatomy

Berger, Bishop, Bettinger 1995

Hagert, E. 2008Nagao, S. et al., 2005

Richard A. Berger, MD, Ph.D., 2003

Labral-like acetabular roof of the dST ligament

Tq

Sc

DIC

Dorsal Scaphotriquetral ligament

DST

D

The 2018 Linscheid-Dobyns Excellence in Wrist Research Award: ASSH

2019

• Isolated SLIL injuries don’t produce DISI

• LRL, STT and DICL are critical lunate stabilizers

• The greatest increase in RLA (DISI) was noted when STT or DICL + DICS were cut

• There is a differential effect of the DICL and DICS

2019

• MRI study: 90 patients with SLIL tear• 2mm or more gap associated with increased

signal in DIC and/or DRC ligament• Reinforces cadaveric studies that show DIC

injury is critical to scapholunate dissociation

JHS 2019

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ARE WE CAUSING DISI?

Berger, RA., Bishop, AT, Bettinger, PC:

Ann Plast.Surg., 1995

**** * * ??

* ** * *

*

IS THE “LIGAMENT SPLITTING APPROACH” LIGAMENT-SPARING? PURPOSE1. Define the anatomy and insertional area

of the DIC, DRC and DST ligaments

2. Establish a novel dorsal surgical “window” approach to the carpus that preserves the dorsal scapholunotriquetral ligament complex

Loisel, F., Wessel, L., Morse, K., et al, JBJS, submitted, 2020

HYPOTHESIS

The “ligament-splitting” approach to the carpus leads to greater kinematic

abnormalities than a “window” approach.

METHODSAnatomy

• 17 FF cadaveric specimens, no prior injury/DJD – 7♂, 10♀ Age: 67.1 (range 48-86)

• DIC and DRC inspected, photographed, measured; then lifted from triquetral insertion

• DST exposed and measured• Scaphoid, lunate and trapezoid insertions

measuredWessel, L., Kim, J., Morse, K. et al, JHS (A), submitted, 2020

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METHODSImaging

• 3 imaged with thin-cut high-res (4T) MR imaging (GE Medical systems) prior to dissection

• Ligaments identified on 0.7-1.0mm serial sections in three planes (axial, coronal, sagittal)

• Bones and ligaments segmented using ITK-SNAP (ver. 3.8.0) [SCI, Univ. Penn]

• 3D interactive carpal model constructed with layered ligaments

• Highest density likely represents most aligned (isometric) ligament fibers

METHODSKinematics

• 24 cadaveric wrist-forearms, no prior injury/DJD• Mounted in a custom frame• 4 phases, each cycled with load

I. IntactII. SLIL cut percutaneouslyIII. Ligament-split vs Window approachIV. Anchor vs “baseball stitch” closure

RESULTSAnatomy

Insertion site MeanArea (mm2)

St. Deviation

Conjoined insertion on the triquetrum 88.5 6.4

DST Insertion on the lunate 59.0 5.0

DST insertion on the scaphoid ridge 23.9 5.4

DRC insertion on the lunate 29.3 27.6

DRC insertion on the radius 66.0 7.9

DIC insertion on the scaphoid ridge 41.4 2.6

DIC Insertion on the trapezoid 46.4 7.7

DIC

DRC

H C S

Anatomy of Dorsal SLT Ligament ComplexOverlying DIC fibers excised for exposure

DSLT

@Lauren Wessel, MD

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Anatomy of Dorsal SLT Ligament Complex

SCH

Overlying DIC fibers excised for exposure

DSLT

@Lauren Wessel, MD Hagert, E. 2008 Wessel/Wolfe modifications, 2020

RESULTSImaging

Hagert, E. 2008 Wessel/Wolfe modifications, 2020

RESULTSImaging

We believe the dorsal scapho(luno)triquetral ligament binds the proximal carpal row, and is the deep anchoring

subcomponent of the DIC. It also represents a dorsal labrum for

the capitate.

The DIC proper overlies the DSLT and attaches

predominantly to the trapezoid & trapezium.

Fiber splitting capsulotomy « Window » approach

APPROACH

RESULTSKinematics

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Fiber splitting capsulotomy Active dorsal scaphoid translation produced

APPROACH

RESULTSKinematics

Fiber splitting capsulotomy « window » approach

CLOSURE

RESULTSKinematics

Mean scapho‐ lunate Gap (mm)

RESULTSKinematics

Mean radio lunate angle (°)

RESULTSKinematics

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CONCLUSIONS• The dorsal SLT ligament complex is

critical to the stability of the proximal row• The DIC, DRC and DST each insert on the lunate• The dorsal scapho(luno)triquetral ligament is the

insertional subcomponent of the DIC• The ligament-splitting approach creates

additional postural and kinematic abnormalities• A window approach enables safe open repair of

the SLIL and DIC/DRC/DST

THANK YOU!!

Lauren Wessel, MDFrancois Loisel, MDAlfonso Perez, MD

Kyle Morse, MDDavid J. Kim, MS

Ubaldo Alaya Gamboa, MD

Matthew Koff, PhDRyan Breighner, PhDKathleen Meyer, MSStephen Doty, PhD

Christian Victoria, MSHollis Potter, MD

© Scott W. Wolfe, MD 2020

The 75th Annual Meeting of the ASSH SYM19: Scapholunate Reconstruction 2020: The Critical Ligaments October 3, 2020

Special thanks to the entire DSLT team:

Funded in part by the American Foundation for Surgery of the Hand, Fast Track Grant #2236

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DISCLOSURES

Greg B. Couzens, MD

Speakers Bureau: Medartis, LMT (Australian

distributor for Trimed, Integra)

Ownership Interests: Shares in Field

Orthopaedics.

Beyond the SLIL:Diagnostic workup of the

critical ligaments of the carpusGreg Couzens, MBBS, FRACS (Orth)

1. Brisbane Hand & Upper Limb Clinic.2. Princess Alexandra Hospital.3. Queensland University of Technology.

ASSH 75

SYM19 – Scapho-lunate Reconstruction 2020: Addressing the Critical Ligaments. 2:30-2:38pm

Extrinsic

ligaments

Dorsal radio-

carpal ligament

Dorsal intercarpal

ligament

Long radio-lunate

ligament

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Xray other side

Courtesy of Mark Ross

RadiusCapitate

Radio-lunate

Luno-capitate

Scapho-lunate

Alignmentof both

sides

Infer ligament injury from plain films

Image critical extrinsic ligaments on MR

Visualise injured structure with arthroscopy

Visualise carpal motion on animated CT

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Infer ligament injury

▪ pattern of static deformity on

plain films

▪ stress films

Image critical extrinsic ligaments on MR

▪ injury to extrinsic ligaments often

identified

▪ Significance varies, needs correlation

with x-rays, clinical findings

Visualise carpal motion on

animated CT

▪ Disruption of normal

smooth pattern of

motion

▪ Excessive motion

Using the method described by Leng et al

2011 & Shore et al 2013

Effective dose: 0.07 mSV per scan

maneuvre equating to <1mSV for entire CT

scan Skin dose: 33mgy / <1mSV

128 slice cardiac CT

4D CT

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Visualise injured

structure with

arthroscopy

▪ Bare area at

site of avulsion

▪ Swollen

ligament

▪ Test integrity of

attachment

Lateral X-Ray

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Lateral X-Ray

99%90%

Viegas, S.

1999

Identify on PDFS sequences

▪ Gradient or T2 weighted for small bony

avulsions

Trace course of ligament in sequential slices

Identify ligament in all three planes

▪ Sagittal sequences will be the most useful

Absence of normal ligament

High signal in ligament

Swelling of ligament

MR Arthrogram only if plain MR unhelpful and

you are convinced of an extrinsic ligament

injury

Magnetic Resonance Imaging

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Attachments of dorsal ligaments

to proximal row

Normal MR

appearance

Dorsal Extrinsic ligaments

▪ Dorsal Radio-carpal

ligament

▪ Dorsal Intercarpal

ligament

DICL

DRCL

Dorsal Extrinsic ligaments▪ Dorsal Radio-carpal

ligament

▪ Dorsal Intercarpal ligament

Normal MR

appearance

Normal triquetral insertion of DIC ligament

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ligament

▪ Dorsal Intercarpal ligament

Normal MR

appearance

Dorsal Extrinsic

ligament injury

▪ Dorsal Radio-

carpal ligament

Positive findings

▪ Swollen

▪ High signal

▪ Absent

Intact

attachment

of DICL

Dorsal Extrinsic

ligaments

▪ Dorsal Radio-

carpal

ligament injury

▪ Intact dSLL

▪ Torn vSLL

▪ Disrupted

DRCL towards

insertion

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ligament

▪ Dorsal Inter-carpal

Ligament

TFC

disc

Dorsal Extrinsic

ligaments

▪ Avulsion injury

▪ Dorsal Radio-

carpal ligament

▪ Dorsal Inter-

carpal Ligament

DRC ligament

stripped up off

insertion


▪ Swelling and disruption

▪ Dorsal Radio-carpal ligament

▪ Dorsal Inter-carpal Ligament

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Course▪ Anterior to

proximal pole

of scaphoid▪ No

attachment to scaphoid

▪ Overlaps

vSLLcompletely

▪ May have attachment to triquetrum

Volar extrinsic ligaments

▪ Long Radio-lunate

ligament

▪ Radio-scapho-

capitate ligament

Normal

appearance

RSC ligRSC lig

LoRL lig

Normal

appearance



ligament

▪ Radio-scapho-

capitate ligament

RSC lig

LoRL lig

RSC lig

LoRL lig

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Normal

appearance



ligament

▪ Radio-scapho-

capitate ligament

RSC ligRSC lig

LoRL lig

LoRL lig

LoRL

LoRL

LoRL

Normal

appearance

PDFS

sequences

RSC

RSC

RSC

Normal

appearance

PDFS

sequences

Long radio-lunate ligament

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Volar extrinsic ligamentsLong radio-lunate ligament

▪ Swollen

▪ High signal

Complete disruption with oedema in lunate



▪ Swollen

▪ High signal

Torn

LoRLL

21 yo

Normal

LoRLL



▪ Swollen

▪ High signal

LoRL Lig.

Near

insertion

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▪ Swollen

▪ High signal

Associated

with non-

displaced

scaphoid

fracture

In plaster

LoRL sprain

LoRL sprain

LoRL sprain


Intact dSLLTorn vSLL and LoRL lig


Torn

Scapholunate

ligament with

intact Long

Radio-lunate

ligament

Acute subtotal SLL

tear with intact LoRL lig

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Arthroscopic

Assessment

▪ Bare area at site of avulsion▪ Swollen ligament▪ Test integrity of attachment

In my (limited) experience▪ DRL avulsion best seen from RC

joint

▪ DICL avulsion best seen from MC joint

▪ Use 6R or 1/2 portal for visualising▪ ‘horizon view’

Tq

Lu

View from

MCR portal

Tq

Lu

Tq

Lu

Lu

Tq

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View from 6R portal

DICL separated from lunate

Swollen SLL

Summary▪ Awareness of patterns of injury.

▪ High index of suspicion

▪ XR contralateral side

▪ Identify critical extrinsic ligaments on

MR

Thankyou

[email protected]

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The Lunate Bare Area and the RADICL (Reduction/Augmentation DICL) repair

Mark Ross Professor of Orthopaedic Surgery

University of Queensland Brisbane Hand and Upperlimb Clinic

Brisbane, Australia

Greg Couzens , Francois Loisel , Scott Wolfe

In relation to carpal instability there has been an excessive focus on intrinsic ligaments • Perhaps we should dispense with the term Secondary stabilisers

• Perhaps extrinsic ligaments are the PRIMARY stabilisers

• DRC and DIC insert on almost the entire non articular surface of dorsal lunate

• In many cases of partial and complete intrinsic ligament injury and in CIND-T there is an identifiable loss of insertion of the extrinsic dorsal capsular ligaments to the dorsal lunate (the pathological “Bare Area”)

Diagnosis of Bare Area • MRI

• MRA?

• A/S

Arthroscopic Assessment of Capsular Attachments • Must put scope in :

• 1/2 or 6 R/U

• MC U or R

Arthroscopic treatment • RADICL

• Repair / Augmentation DICL ( DRCL)

G2 / Ewas 3

• Symptomatic after trial of rehab

• Rupture volar band SLIL

• Intact dorsal band SLIL

• Assess for Luante Bare area ( MRA or A/S)

• Reattach – A/S RADICL

Arthroscopic treatment of acute perilunate

• Radicl repair can form part of repair

Implications for Open Treatment

• Avoid “creating” detachment of capsular attachment to dorsal lunate through surgical approach

• Favour window approach

• If lunate Bare Area identified during reconstruction ensure reattachment performed as part of repair

Summary

• PRIMARY Stabilisers

o LRL o vSTTJ , o DICL/DRCL

• Extrinsic ligaments→ primary stabilisers

• Assess and treat in all grades of carpal instability

• Identify dorsal capsular dissociation from lunate – Dorsal Lunate Bare Area

• MRI vs MRA not resolved

• A/S – must use correct portals and look for lesion – easy to miss from 3/4 portal

Summary - Treatment

– Don’t make it worse with approach – capsular windows

– Reattach dorsal ligaments to lunate in A/S and open cases

• A/S -Partial SL – G2/ EWAS 3

• A/S - (?)Dynamic SL – G3/ EWAS 4

• CINDT DISI and VISI

• Open – after reconstruction

• A/S – Perilunate

30-Aug-20

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Targeting the palmar and dorsal critical

stabilizers: Novel techniques to address

DISI and carpal translation.

Michael J. SANDOW FRACS PhD

Wakefield Orthopaedic Clinic

&

Centre for Orthopaedic and Trauma Research

University of Adelaide

Adelaide

Declaration of InterestI declare that in the past three years I have:

• held shares in: True Life Anatomy (3D Imaging Technology)

Macropace Products

RuBaMAS

• received royalties from: nil

• done consulting work for: nil

• given paid presentations for: nil

• received institutional support from: nil

Signed: Michael JSandow

Developing interactive 3D imaging since 1997.

1998 1999 2001

Disclosure / COI

True Life Anatomy

How do you explain the wrist?

Why has the Wrist been so difficult to sort?

All wrist are different

Current “theories” generally based on attempts to reconcilevoluminous empirical observations

all wrists perform basicallythe same functions and tasks

6

Unifying model of carpal mechanics based on computationally derived

isometric constraints and rules-based motion

– the stable central column theory

M. J. Sandow, T. J. Fisher, C. Q. Howard, S. Papas

May 2014

30-Aug-20

2

The complexities of wrist function are enabled by the presence of the Stable Central Column

>> Radius > lunate > capitate > 2/3rd metacarpal

VOLAR

DORSAL

L-TqLongR-LSc-Tm

Sc-L

3D CT models in: RD / Neutral / UD

➢ ISOMETRIC CONNECTIONS

Each row – proximal / distalOnly moves in a single

FLEXION – EXTENSION axis

Same ISOMETRIC Constraints for RD/UD and Flex/Extend

Moritomo -2006Distal row motion is

uniaxial with the scaphoid

Two single axis cylinders with variable offset

When cylinders in line and moving in same direction

>> Flexion / Extension

When offset and moving in opposite directions

>> Radial / Ulnar deviation Flexion Extension

30-Aug-20

3

Radial Deviation Ulnar Deviation

Carpus - Two linked Rows

The combined binary output of two offset unitary arc joints,

→ two degrees of freedom

Each moves througha single arc of motion

components and they can each vary, but in combination create function

>> Rules Based Motion

1. Bone morphology

2. (Isometric) constraints

3. Surface interaction

4. Load

shape x linkage x friction x force = Wrist function

Four components / rules

16

Unifying model of carpal mechanics based on computationally derived

isometric constraints and rules-based motion

– the stable central column theory

M. J. Sandow, T. J. Fisher, C. Q. Howard, S. Papas

May 2014

- the stable central column theory -

30-Aug-20

4

What controls Lunate Extension

DCSS

LRL

dSLIL

LTq

What controls Lunate Flexion

Ref: C. Mathoulin

“Scapho-lunate” gapOnly measurable in 2D on x-rays and CT

? Radiological gap

? SLIL attachments

? Dorsal displacement of Scaphoid

3mm

17.3mm

Pre-operative

“2D” X-ray Gap

“3D” S-L Gap

7.4mm

3mm

17.3mm

Pre-operative Computer (virtual) reduction

“2D” X-ray Gap

“3D” S-L Gap “3D” S-L length

Ligaments creating oblique external linkage, with translation creating rotationally stable carpus on radius

Adding the short Radio-Lunate ligament prevent distraction

Two Degrees of Freedom➢ Flexion / Extension

➢ Radial Dev / Ulnar Dev

30-Aug-20

5

If we can understand how the wrist works, then can work out how to fix it when it does not!

FCR stripSynthetic tape

(anchor)No K-wires

ANAFAB (for Scapho-lunate dissociation)Anatomical Front and Back Reconstruction

Technique overview:www.woc.com.au/ANAFAB

November 2019

The Stable Central Column Theory explains how the wrist works

and how to fix it.

www.woc.com.au/Wrist_explainedwww.woc.com.au/wrist.pdf

sym19: scapholunate reconstruction 2020: addressing the

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