central dorsal zone

Question 1

Central dorsal zone structures

Answer 1

1. Lister’s tubercle
2. Dorsal rim radius
3. Lunate
4. Scapholunate interval
5. dorsal wrist ganglion
6. ECRL, ECRB tendons

Question 2

most likely central dorsal zone structures

Answer 2

1. SL ganglion
2. SL ligament injury
3. ECRB, ECRL tendons
4. Lunate

Question 3

Lister’s tubercle

Answer 3

MOI: Common in gymnasts: gymnast’s wrist – repetitive loading OR acute fracture

Palpate Lister’s Tubercle + Dorsal Rim Radius

Question 4

Lunate - KEINBOCK’S DISEASE

Answer 4

• Avascular necrosis of lunate
• MOI: FOOSH or repeated trauma
• Complains of: Chronic dorsal or volar wrist pain & Loss of grip strength

Ax: Start at Lister’s tubercle, move distally and ulnarly. Lunate more prominate in wrist flexion.
Tenderness: may be Kienbock’s

differential:
• Scaphoid #
• TFCC tear
• Avascular necrosis of scaphoid

Question 5

Lunate - KEINBOCK’S DISEASE Mx

Answer 5

\+ xray
Acute
•	Immobilisation
Chronic
•	Surgery (refer for x-ray for confirmation)
•	Revascularisation with bone graft
Prognosis: 6-8 weeks to heal

Question 6

SL/ dorsal wrist ganglion

Answer 6

• Commonly at scapholunate joint
• Fluid-filled cyst on dorsal aspect of the hand that arises from synovial joints or tendon sheaths herniated fluid cyst
• Benign and often asymptomatic can disappear spontaneously

MOI: insidious

Ax: May have visible lump in the wrist (cyst or herniation)
More evident in wrist flexion, light shines through it
Not to be confused with carpal bos

Question 7

SL/ dorsal wrist ganglion Mx

Answer 7

Conservative
• pain may subside with rest
o wrist immobilisation in a splint for 2-4 weeks to ‘quiet’ the discomfort
o uncommon for immobilisation to resolve a ganglion

Surgery (ganglionectomy)
• Aspiration
o Recurrence rate of 10-15%
o Scar management

Question 8

CARPAL INSTABILITIES (SCAPHOLUNATE INSTABILITY)

Answer 8

o Scapholunate instability: DISRUPTION OF SL LIGAMENTS
• Scaphoid naturally wants to flex
o Triquetrum wants to extend
o Lunate goes along with triquetrum
• Angle between scaphoid and lunate that is greater than 60 degrees from a lateral view = DISI (dorsal intercalated segmental instability)
• Symptoms are due to excessive movement between the scaphoid and the lunate

•	MOI
o	Ligament tear resulting from FOOSH
o	Degeneration of ligaments (work)
•	Complaints:
o	Dorsal central pain
o	Pain or clicking at the joint with activity

Ax: 
Physical examination
•	Palpation: scapholunate interval 
o	Dorsal central pain and swelling
•Movement exam
o	Glides  to test SL ligament
•	Positive signs: Watson’s test/scaphoid shift test
o	Positive with pain or clunk
o	NB: 1/3 people have a shift normally so compare sides

Question 9

Watson’s shift test: biomechanics

for SL instability

Answer 9

• In a normal wrist, the proximal row of carpals (scaphoid, lunate, and triquetrum) move as a single unit. They flex in wrist flexion or radial deviation and extend in wrist extension or ulnar deviation.
• In a normal wrist, when starting Watson’s test in ulnar deviation, the scaphoid will initially be in extension (i.e. not prominent under the examiners thumb). As the wrist is bought into radial deviation, the scaphoid will flex and become more prominent under the examiners thumb
• In an abnormal wrist (SL ligament tear) the scaphoid will not push into the examiners thumb when the wrist is bought into radial deviation and therefore when the thumb is let go, the scaphoid will ‘shift’ with a clunk back into position.

Question 10

CARPAL INSTABILITIES  (SCAPHOLUNATE INSTABILITY)
Mx

Answer 10

differential diagnosis:
• Scaphoid fracture
• Lunate fracture
• TFCC tear

considerations: 
•	Extent of ligament injury
•	Repairability: healing potential
•	Reductibility
•	Status of cartilage

Grades
•	Grade 1: immobilise, therapy (4 weeks)
o	Initial immobilisation in splint
o	Commencement of ROM
o	Exercises	
-	Dart throwing motion
-	Highly function- radial extension to ulnar flexion
-	Most stable position for proximal carpal row
•	Grade 2: surgical, pinning, thermal, shrinking, repair, capsulodesis
•	Grade 3: open repair, fusion
Manual therapy
•	Avoid grip strengthening  compresses down, avoid WB
•	Proprioception retraining
o	Open chain
o	Power ball
o	Slosh pipes
o	Bod blades

Question 11

ECRB, ECRL tendinopathy

Answer 11

MOI: overuse
Ax: Physical examination
•	Palpation
o	Pain and tenderness
o	Local swelling
•	Movement exam
o	Pain on resisted wrist extension - 
Manual muscle testing for ECRL and ECRB
o	Pain after repeated mvmt with stiffness after a period of rest
-	i.e. morning stiffness

Question 12

ECRB, ECRL tendinopathy Mx

Answer 12

• deload
• address biomechanics
• ADL modifications
• Gradually reload to facilitate healing