Flashcards in Wrist Deck (57):
Ossification begins where in carpal bones?
Capitate (present at 1 year)
Ossification order of carpal bones?
Last carpal bone to ossify?
Pisiform (9 years)
Order of carpal ossification?
Location of ossification centers for metacarpals?
Body (primary--8 weeks gestation) and neck (secondary--3 years)
Which metacarpal is a primordial phalanx and why?
First metacarpal--its secondary ossification center is located at the base (like the phalanges)
Which metacarpal has a styloid process?
Which metacarpal has a tubercle and what attaches there?
5th (small) = ECU
Strongest ligament of radiocarpal joint?
Palmar/volar radiocarpal ligament
Where is the weak spot of the volar radiocarpal ligament?
Space of Poirier (radial side)--lends less support to the scaphoid, lunate and trapezoid
Scaphoid, lunate, triquetrum
Strongest ligaments of dorsal row?
Dorsal intercarpal ligaments
Which ligaments help extend the pull of the FCU?
Pisohamate and pisometacarpal ligaments
Trapezium, trapezoid, capitate, hamate
How many synovial sheaths are in the extensor retinaculum?
1st dorsal compartment?
1) APL--contains multiple tendon slips which should be addressed during de Quervain's
2nd dorsal compartment?
3rd dorsal compartment?
4th dorsal compartment?
2) extensor indicis proprius
5th dorsal compartment?
6th dorsal compartment?
de Quervain's involves which tendons?
APL and EPB
Intersection syndrome (extensor tendinitis)
ECRL and ECRB
Which tendon passes around Lister's tubercle?
EPL--can be ruptured after wrist fxs
What tendon can rupture in RA and Vaughn-Jackson syndrome?
What tendon can snap at the ulnar styloid?
Transverse carpal ligament attachments?
Medially = pisiform and hook of hamate
Laterally = tuberosity of scaphoid and ridge of trapezium
What wrist motion decreases volume of carpal tunnel?
Contents of carpal tunnel?
Median n, FPL, 4 FDS, 4 FDP
Orientation of tendons in carpal tunnel?
FDS of middle and ring fingers are volar to tendons of index and small fingers
Floor of Guyon's canal?
Roof of Guyon's canal?
Volar carpal ligament
Sagittal band action?
Transverse (sagittal) band action?
MCP flexion (interossei)
Lateral band action?
PIP extension (lumbricals)
Oblique retinacular ligament (Landsmeer) action?
DIP extension (passive)
How many annular pulleys and cruciates?
A1-5 and C1-3
Which pulleys attach to bone?
A2 and A4 (A1, 3, 5 orignate from palmar plates of metacarpal, PIP, and DIP joints)
Most critical pulley?
A2 (covers proximal phalanx), followed by A4 (covers middle phalanx)
Which pulley involved in trigger fingers?
Which branch of the median n enters wrist proximal to TCL?
Palmar cutaneous branch--innervates thenar skin
Superficial branch of ulnar n innervates what?
Palmaris brevis and skin
Deep branch of ulnar n passes bt what 2 muscles?
Abductor digiti minimi and flexor digiti minimi brevis
Radial artery reaches the dorsum of the carpus by passing bt what structures?
2) APL and EPB tendons (snuffbox)
Deep palmar arch of hand?
Superficial palmar arch of hand?
Blood supply to scaphoid?
Dorsal carpal branch of radial a
What artery lies on the TCL?
Surgical approaches to wrist?
1) Dorsal wrist
2) Volar (Russe's) wrist
3) Volar scaphoid
4) Dorsolateral scaphoid
Interval for dorsal approach?
1) 3rd extensor compartment (EPL)
2) 4th extensor compartment (ED)
Risk during dorsal approach?
Interosseous scapholunate ligament
What line is used to make incision during CTR?
Kaplan's line--from crease of thumb to hook of Hamate
Intersection of Kaplan's line and webspace of 2-3rd digits?
Recurrent motor branch of median n
Interval of volar (Russe's) approach?
2) Radial a
How do you protect superficial radial n and radial a during the dorsolateral approach?
Make incision within anatomic sniffbox
Volar approach to flexor tendons (zigzag incision)