ulnar wrist pain and salvage procedures

Question 1

DRUJ- where is axis of rotation and greatest bony contact?

Answer 1

greatest bony contact in neutral forearm - sigmoid notch to ulnar head. Axis of rotation is from ulnar head>radial head

Question 2

what position does ulnar head move during pronation

Answer 2

more distal, more dorsal ~ 2mm

Question 3

components of TFCC (6)

Answer 3

dorsal and palmar radioulnar ligaments (deep and superficial 4 total) ;

ulnocarpal ligaments;

ECU tendon sheath/

ulnar collateral ligament;

meniscus homologue;

articular disc

Question 4

what is taut? TFCC in pronation

Answer 4

superficial DRUL, Deep PRUL

Question 5

what is taut? TFCC in supination

Answer 5

superficial PRUL, Deep DRUL

Question 6

normal force distribution through wrist

Answer 6

80% scaphoid/lunate> radius; 20% triquetrum>TFCC>ulna

Question 7

Positive ulnar variance- what is impact on force transmission

Answer 7

60% of load to radius, increase stress on lunate and triquetrum; 40% on ulnar = double

Question 8

positie ulnar variance causes

Answer 8

distal radius fractures, TFCC tears

Question 9

positive ulnar variance can cause…

Answer 9

ulnar impaction syndrome

LT tears

Question 10

ulnocarpal abutement syndrome (impaction, loading, impingement)
Definition? Causes? Symptoms?

Answer 10

degenerative syndrome associated with + ulnar variance. wearing of articular disc of TFCC> chondromalacia of ulnar head and ulnar aspect of lunate>disruption of LT ligament.

causes: malunion radial shortening or dorsal angulation, DRUJ ligament injuries,

Sx: pain dorsal lateral wrist, clicking, dec strength and motion

Question 11

GRIT test

Answer 11

For ulnocarpal abutment “Gripping rotary impaction test”. Measure grip strength in 3 forearm positions, Sup/Pro value calculated as ratio. Ratio >1=potential for impaction or radial disc tear

Question 12

surgical tx of ulnar abutment

Answer 12

ulnar shortening osteotomy if radial alignment good;

bad radial alignment= corrective radial osteotomy vs. radial lengthening vs. Darrach

Question 13

normal distal radius anatomy

Answer 13

21-25* radial inclination

10-13mm radial height

11* palmar tilt

Question 14

ulnar styloid impaction syndrome

Answer 14

ulnar styloid tip + triquetrum - excessively long ulnar styloid. avoid wrist flex/UD, OR partial resection

Question 15

S shape of the wrist

Answer 15

DRUJ instability - ulnar head prominence, S shape from radial shortening, + ulnar variance

Question 16

After TFCC injuries- what is progression of exercise/strengthening?

Answer 16

start in supination, pronation harder/more painful

Question 17

negative ulnar variance is associated with…

Answer 17

Kienbocks disease - AVN of lunate

Question 18

4 stages of Kienbock’s

Answer 18

1. linear compression fx of lunate,
2. abnormal density,
3. lunate collapse,
4. extensive arthritic changes

Question 19

Kienbocks disease treatment

Answer 19

RADIAL SHORTENING, STT fusion, ulnar lengthening, capitate shortening (HORI), vascular bone graft to lunate, salvage procedures if stage 4 - PRC, TWA, denervation)

Question 20

Darrach Procedure

Answer 20

distal ulna resection, ulnar stump remains and can be unstable, elderly or not active patients,

Question 21

Suava-Kapandj

Answer 21

fusion of DRUJ + pseudoarthrosis in distal ulna, TFCC and ECU remain stable ,

Question 22

Bower’s Hemiresection interposition arthroplasty

Answer 22

resect articulating portion of ulna and interpose soft tissue - does not correct ulnar + or DRUJ instability

Question 23

one bone forearm

Answer 23

fusion - elimainates all rotation

Question 24

DRUJ prosthesis

Answer 24

bipolar vs. unipolar

Question 25

LT special tests

Answer 25

ballotment, shear test, ulnar snuffbox compression