Hand Anatomy

Question 1

CMC Joint

Answer 1

Carpals at the wrist articulating with the
Metacarpals of the hand.
Little motion at 2nd and 3rd digits, a bit more at 4th and 5th, a
great deal at the thumb (1st digit) that is a saddle joint.

Question 2

Ray

Answer 2

Includes metacarpal bone and all phalanges, referred to related to amputation

Question 3

How are the joints of the 1st digit, thumb, different than the other digits?

Answer 3

The
thumb has only an IP joint, as there is only one - no distal or proximal. The CMC is
much more mobile than the other digits with a large loose joint capsule to allow so much
motion, but the MCP is less mobile than the other digits allowing only flexion and
extension.

Question 4

What is the “keystone” of the proximal transverse arch?

Answer 4

The Capitate

Question 5

What is the “keystone” of the distal transverse arch?

Answer 5

The 2nd and 3rd MCP Joints

Question 6

What is the “keystone” of the longitudinal arch?

Answer 6

The 2nd and 3rd MCP Joints

Question 7

Which CMC joint in the hand is the most mobile?

Answer 7

The 1st CMC (thumb)

Question 8

Which two CMC joints are the most stable?

Answer 8

The 2nd and 3rd (index and middle)

Question 9

What is the function of the volar plates at the fingers?

Answer 9

To prevent hyperextension of

the joints and to increase the surface area to allow increased ROM.

Question 10

What is the function of the palmar fascia?

Answer 10

Protection of the underlying structures and

improved grip

Question 11

What is the function of the collateral ligaments at each joint?

Answer 11

To prevent any, or

excessive abduction/adduction at that joint - increase stability.

Question 12

Describe the difference in Skier’s Thumb and Gamekeeper’s Thumb:

Answer 12

Skier’s is
related to an acute trauma while Gamekeeper’s is related to a gradual onset wearing of
the UCL at the MCP of the thumb until it ruptures.

Question 13

Describe the differences between Gamekeeper’s Thumb and Bennett Fracture:

Answer 13

Gamekeeper’s and Skier’s Thumb occur at the MCP, Bennett Fracture and Rolando
Fracture occur at the CMC of the thumb.

Question 14

What is Dupuytren’s Contracture?

Answer 14

Contracture - shortening and thickening of the
palmar fascia into rope-like cords that limit extension of the digits affected. More
common in men of Northern European descent, and more common in 4th or 5th digit.

Question 15

What structures run through the carpal tunnel and what are the symptoms of
carpal tunnel syndrome?

Answer 15

4 tendons of the FDS, 4 tendons of the FDP, 1 tendon of the
FPL, Median Nerve. Symptoms are numbness, tingling, burning in the thenar eminence
and digits 1-3 or if severe also atrophy of the thenar eminence muscles (FPB, APB,
OP).

Question 16

Which bone is considered the “keystone” or central anchor point of the longitudinal arch of the hand?

Answer 16

The Capitate

Question 17

What motion is limited by the volar plate at the PIP?

Answer 17

Hyperextension

Question 18

Which joint is MOST mobile in the hand?

Answer 18

CMC of the 1st digit

Question 19

Which digit has the least number of joints?

Answer 19

1st

Question 20

In the thumb, Rolando/Bennett fractures happen at the ________ joint, whereas Skier’s/Gamekeeper’s Thumb happen at the _________ joint

Answer 20

CMC, MCP

Question 21

he function of the lumbricals is

Answer 21

MCP flexion, DIP & PIP extension

Question 22

The name of the area where the FDP tendon comes up through the split FDS tendon is: *

Answer 22

Camper’s Chiasm

Question 23

The most important pulleys around the flexor tendons of the hand, in terms of preventing bowstringing of the tendons are the:

Answer 23

A2 & A4