hand

Question 1

1st CMC saddle joint:

Answer 1

• BIAXIAL
• F–E in plane o fpalm 
• ABD–ADD
perpendicular to palm
 OPPOSITION = F + ABD + MR
CONJUNCT ROTATION occurs as a consequence of the oblique CMC ligaments

Question 2

2nd – 5th CARPOMETACARPAL JOINTS: Common joint capsule

Answer 2

2nd MC wedged / least mobile
Mobility increases 2nd to 5th 2nd – 4th plane synovial
5th = saddle

Question 3

METACARPALPHOLANGEAL JOINTS

Answer 3

1ST – 5TH = BIAXIAL ellipsoid joint 
•F–E
• ABD – ADD
1ST MCP = variable ABD – ADD less mobile than 2nd – 5th MCP’s
NO hyperextension
UCL of the 1st MCP
Resists valgus re pinch grip
•Loose joint capsule
•Large metacarpal head + small base of phalanx

Question 4

Metacarpophalangeal (MCP) joints: Volar plate

Answer 4

fibrocartilage plate attached to base of phalanx
•Proximally continuous with volar capsule
•Increases joint contact area
•Protects volar side of joint when gripping/manual activities

Question 5

INTERPHALANGEAL JOINTS:

Answer 5

• Synovial hinge joints
• Collateral ligaments & volar plates •Little or no hyperextension
• IP of the 1st is least mobile
• Most finger F occurs at PIP joints

Question 6

volar aspect of the head of the metacarpal

Answer 6

is wider than the dorsal aspect. collat. lig are taut in flx.

Question 7

bases of the intermediate and distal phalanges

Answer 7

have double facets for the phalangeal trochlea.

Question 8

HAND FORCE TRANSFER

Answer 8

• 2nd & 3rd MC
• Capitate
• Scaphoid > Lunate
• Distal radius > Ulna
• Proximal ulna > radius
• Humerus