Wrist and Hand

Question 1

What type of bone are metacarpals? phalanges? carpals?

Answer 1

metacarpals and phalanges are long bones; carpals are short bones

Question 2

What is the radiocarpal joint? What is its structural classification?

Answer 2

radius with the scaphoid and lunate; synovial ellipsoid joint

Question 3

What is the structural classification of the mid carpal and intercarpal joints?

Answer 3

gliding joints

Question 4

What does the midcarpal joint space consist of?

Answer 4

all carpal bones except pisiform

Question 5

What does the distal row consist of? How does it move?

Answer 5

trapezium, trapezoid, capitate, hamate; moves as a unit

Question 6

What does the proximal row consist of? How does it move?

Answer 6

scaphoid, lunate, triquetrum, pisiform; moves independently

Question 7

What carpal bone moves most independently?

Answer 7

scaphoid- can move independent to lunate and in different directions

Question 8

How does the proximal and distal row contribute to flexion-extension?

Answer 8

similar contributions to ROM from the proximal and distal rows

Question 9

How does the proximal and distal row contribute to abduction-adduction?

Answer 9

distal row follows the fingers; proximal row moves in opposite direction (note- during abduction the scaphoid flexes to avoid impinging on the radial styloid)

Question 10

What are the attachments of the radial collateral ligament?

Answer 10

radial styloid -> scaphoid

Question 11

What are the attachment of the ulnar collateral ligament?

Answer 11

ulnar styloid -> triquetrum

Question 12

What does the palmar radiocarpal ligament resist?

Answer 12

excessive wrist extension

Question 13

What does the palmar ulnocarpal ligament resist?

Answer 13

excessive wrist extension

Question 14

What does the dorsal radiocarpal ligament resist?

Answer 14

excessive wrist flexion

Question 15

What are the intrinsic ligaments? Where are the attachments?

Answer 15

palmar midcarpal ligament, dorsal midcarpal ligament, interosseous ligament between adjacent carpal bones (all attachments are within the carpal region)

Question 16

What would occur if the ulna was shorter than the radius?

Answer 16

ulna shorter=negative ulnar variance (not going to have force going through triquetrum and lunate to the TFCC to the ulna; more force loading to your radius putting it at risk also removing support for lunate)

Question 17

What would occur if the ulna was longer than the radius?

Answer 17

ulna longer=positive ulnar variance (TFCC loading- compressing TFCC)

Question 18

What does the radius articulate with?

Answer 18

scaphoid and lunate

Question 19

What carpal bone has the greatest contact with the radius?

Answer 19

scaphoid

Question 20

What does the TFCC articulate with?

Answer 20

lunate and triquetrum

Question 21

Does the wrist have greater range of flexion or extension?

Answer 21

flexion

Question 22

Does the wrist have greater range of abduction or adduction?

Answer 22

adduction

Question 23

What is the significance of a ligamentous injury on the carpal bones?

Answer 23

if someone has ligamentous injury (such as rheumatoid arthritis) than you get a carpal drift or deformity (carpal drifts when you take away their ligamentous support) (each carpal bone drift towards the ulnar in an anterior direction)

Question 24

What is the most common carpal fracture? Why?

Answer 24

scaphoid bc it is the bone that receives the most force and has greater contact with the radius

Question 25

What is avascular necrosis?

Answer 25

death of bone tissue due to a lack of blood supply which can lead to tiny breaks in the bones and bones eventual collapse

Question 26

What carpal is the key stone of the proximal row? Why?

Answer 26

lunate; it is important to the stability of the proximal row- since no muscles attach to it, its stability relies on the shape of articular surfaces and ligaments

Question 27

What is scapholunate dissocation?

Answer 27

capitate pushes through and seperates the lunate and scaphoid disrupting the scapholunate ligament

Question 28

What is the structural classification and movements of the 1st carpometacarpal joint?

Answer 28

structural classification- synovial saddle movements- F-E in plane of palm, Abd-Add perpendicular to palm, opposition- abd+f+mr, conjuct (medial) rotation occurs as a consequence of the oblique CMC ligaments tightening

Question 29

What is the structural classification and movements of the 2nd-4th carpometacarpal joints?

Answer 29

structural classification- synovial plane movements- gliding (2nd MC wedged/least mobile, most stable)(mobility increases 2nd to 5th)

Question 30

What is the structural classification and movements of the 5th carpometacarpal joint?

Answer 30

structural classification- synovial saddle | movements- F-E, Abd-Add/gliding

Question 31

What is the structural classification and movements of the 2nd-5th intermetacarpal joints?

Answer 31

structural classification- synovial plane | movements- gliding

Question 32

What is the structural classification and movements of the 1st-5th metacarpophalangeal joints?

Answer 32

structural classification- synovial ellipsoid movements- F-E, Abd-Add (1st is most stable, function relevance- good to have mobility at CMC to oppose and then less mobility at your MCP)

Question 33

What is the structural classification and movements of the 1st-5th interphalangeal joints?

Answer 33

structural classification- synovial hinge movements- F-E (IP of the 1st is least mobile, PIP increasing ROM from 1st-5th, most finger flexion occurs at PIP joints)

Question 34

What are the thenar hand muscles?

Answer 34

abductor pollicis brevis, flexor pollicis brevis, opponens pollicis

Question 35

What is the common proximal attachment between all the thenar hand muscles?

Answer 35

flexor retinaculum and trapezium

Question 36

What are the hypothenar hand muscles?

Answer 36

abductor digiti minimi, flexor digiti minimi brevis, opponens digiti minimi