Carpal

Instability By: Fahad Al Hulaibi Orthopedic Resident

National Guard Hospital - 2015

- Definitions

- DISI

- VISI

- Mid-carpal CIND

- Radio-carpal

dislocation

- Peri-lunate

dislocation

Objective:

definitions

Definitions:

Dynamic instability - (incomplete injury)

maintains normal alignment at rest but will

collapse under applied load.

Carpal Instability

Static Instability - (complete injury)

abnormal intercarpal alignment on static

radiographs.

Carpal Instability

Carpal Instability – Dissociative:

Instability occurs between the individual

bones. (in the same row) E.g: DISI & VISI

Carpal Instability

Carpal Instability – Non-Dissociative:

Instability occurs between the row of

bones

Carpal Instability

DISI “Dorsal intercalated segmental instability”

Carpal Instability

DISI

Scapholunate ligament disruption.

Dorsal ligaments are stronger.

scaphoid will hyperflex. and the lunate will

hyperextend.

Carpal Instability

Presentation

Hx:

acute FOOSH injury vs. degenerative

rupture

Symptoms:

dorsal and radial-sided wrist pain

Carpal Instability

Examination:

- Dorsal wrist pain.

- Diminished grip strength.

- pain increased with extreme wrist

extension and radial deviation

Carpal Instability

Watson test

Palpable clunk

Carpal Instability

Terry Thomas sign

Static &

Dynamic

>3 mm

Carpal Instability

Terry Thomas sign

Static &

Dynamic

>3 mm Clenched-fist

Carpal Instability

cortical ring sign

Duo to frontal projection of volar tubercle

Carpal Instability

SL angel:

Carpal Instability

Treatment

• acute, undisplaced

• chronic, asymptomatic NSAIDS, rest +/- immobilization

• SL ligament injury W/o carpal malalignment

• reducible SL ligament injuries

SL reconstruction

• rigid and unreducible

• DISI with severe DJD wrist fusion

Carpal Instability

Scapholunate advanced collapse (SLAC)

untreated DISI deformity

Carpal Instability

VISI “Volar intercalated segmental instability”

VISI

Instability of the lunotriquetral ligament.

Volar ligaments are stronger.

scaphoid & Lunate will hyperflex.

Carpal Instability

Presentation

Symptoms:

Ulnar side wrist pain

Increase with ulnar deviation

Carpal Instability

Ballottement test

Laxity, crepitation or reproduction of pain

Carpal Instability

Gilula arc on AP

Break this line

Carpal Instability

< SL angel on Lateral

Carpal Instability

Treatment

• acute instability

CRPP with

lunotriquetral repair

• chronic instability

LT fusion

• chronic instability secondary to ulnar positive variance

arthroscopic debridement

with ulnar shortening

Carpal Instability

Carpal instaability

Dissociative(CIND)

CIND

Midcarpal instability

Radiocarpal dislocation

Carpal Instability

Extrinsic ligamentous

disruption.

- radioscaphocapitate (SRC)

- long radiolunate

- short radiolunate

- radioscapholunate

Carpal Instability

Carpal Instability

Associated conditions:

Intracarpal injury (scapholunate or

lunotriquetral ligament)

acute carpal tunnel syndrome

compartment syndrome

Carpal Instability

Prognosis:

Volar dislocation more severe than dorsal.

Carpal Instability

Presentation:

No history of trauma (midcarpal)

High energy trauma (radiocarpal)

generalized ligamentous laxity

irritating clunking sign

complain of wrist giving way

Carpal Instability

Radiocarpal dislocation

Carpal Instability

Carpal Instability

Treatment

• first line of treatment immobilization +/- splinting

• ulnar translation with styloid fractures

open repair, reduction, and

pinning

• failed nonoperative management

midcarpal joint fusion

• distal radius malunion Osteotomy

• failure of above treatments

wrist arthrodesis

Carpal Instability

Peri-lunate dislocation

mechanism

Forced dorsflextion,

Ulnar deviation

Supination.

Carpal Instability

25% are missed in the ER

diagnosed

75%

missed

25%

Carpal Instability

Mayfield

commonly associated with a scaphoid fracture

Carpal Instability

Stage I :

scapholunate dissociation

Stage II:

+ lunocapitate disruption

Stage III:

+ lunotriquetral disruption,

"perilunate“

Stage VI:

Lunate Dislocation

Most severe of carpal instabilities

space of

Poirier

break in Gilula's arc

Carpal Instability

triangular lunate

"piece-of-pie sign"

Treatment

• definitive management

Closed reduction and

casting

• all acute injuries <8 weeks old

closed reduction/splinting followed by open reduction,

ligament repair, fixation, possible carpal tunnel release

• chronic injury (defined as >8 weeks after initial injury)

Proximal row carpectomy

• chronic injuries with degenerative changes

Total wrist arthrodesis

Carpal Instability

Summery:

Carpal Instability

Case 1

Lunate dislocation

Sources: Review of Orthopaedics, 6th Edition, Mark D. Miller MD, Stephen R.

Thompson MBBS MEd FRCSC, Jennifer Hart MPAS PA-C ATC, an imprint of Elsevier, Philadelphia, Copyright 2012

AAOS Comprehensive Orthopaedic Review, Jay R. Leiberman.

Published by American Academy of Orthopaedic Surgeons, Rosemont IL. Copyright 2009

Orthopaedic Knowledge Update 10, John M Flyn. Published by American Academy of Orthopaedic Surgeons, Rosemont IL. Copyright 2011

Hoppenfeld SP. Surgical Exposures in Orthopaedics: The Anatomic

Approach. Lipponcott, Williams, and Wilkins, Philadelphia, PA, Copyright 2009

Orthopaedic In-training Examination (OITE) Questions 2004-2012, American Academy of Orthopaedic Surgeons, Rosemont IL. Copyright 2004-2012

Self-Assessment Examination (SAE) Questions 2004-2012, American Academy of Orthopaedic Surgeons, Rosemont IL. Copyright 2004-2012