The Wrist- Palastanga

Question 1

What joints functionally comprise the wrist

Answer 1

Intercarpal, midcarpal and radiocarpal articulations

Question 2

Classification of the radiocarpal joint

Answer 2

Synovial ellipsoid

Question 3

Articular surfaces of the radiocarpal (rc) joint

Answer 3

Distal radius and articular disc with scaphoid, lunate and triquetral of the proximal row of carpals

Question 4

When combined with supination/ pronation at the forearm the hand appears to move as

Answer 4

A ball and socket

Question 5

Why is there great inherent stability at the wrist/ hand

Answer 5

Because of the separation of the 3 axes about which movement occurs
Also because of the flexor retinaculum and many tendons crossing the region

Question 6

Describe the joint capsule of the rcj

Answer 6

Fibrous completely enclosing the joint
Thickened anteriorly and posteriorly and hence strengthened in these regions
Blends with collateral carpal ligaments medially and laterally

Question 7

Capsular ligaments of the rcj

Answer 7

Dorsal radiocarpal
Palmar radiocarpal
Palmar ulnocarpal

Question 8

Functions of the capsular ligaments of the rcj

Answer 8

Strengthen the capsule and determine that the hand follows the radius in its movements and displacements
Are taut in flexion and extension

Question 9

Other supporting ligaments of the rcj

Answer 9

The collateral ligaments
Radial collateral carpal ligament is taut and limits adduction
Ulnar collateral carpal ligament is taut and limits abduction

Question 10

Movements possible at the rcj

Answer 10

Flexion/ extension

Abduction/ adduction

Question 11

Describe flexion/ extension at the rcj

Answer 11

Occur about a transverse axis more or less in the sagittal plane
Flexion freer than extension

Question 12

ROMs of flexion/ extension at the rcj

Answer 12

Flexion max 50d

Extension max 35d

Question 13

Describe abduction/ adduction at the rcj

Answer 13

Also referred to as radial and ulnar deviation respectively

Movement of proximal row of carpals in relation to the distal radius

Question 14

Which movement of ab/adduction at the rcj is more limited and why

Answer 14

Abduction/ radial deviation is more limited due to the further extension of the radial styloid process compared to the ulnar styloid process

Question 15

ROMs of ab/adduction of the rcj

Answer 15

Abduction/ radial deviation = 7d

Adduction/ ulnar deviation = 30d

Question 16

How are the carpal bones arranged

Answer 16

Into 2 rows, proximal and distal, between which lies the midcarpal joint

Question 17

Classification of the intercarpal joints (icj)

Answer 17

Most are plane synovial and have various ligaments between them permitting very little movement

Question 18

Articular surfaces of the midcarpal joint (mcj)

Answer 18

Laterally - trapezium and trapezoid with scaphoid forming a slight convexity
Medially/ centrally - capitate with scaphoid and lunate, also hamate with lunate and triquetral forming a slight concavity

Question 19

Describe the joint capsule of the mcj

Answer 19

Composed primarily of irregular fibrous bands running between the 2 rows of bones
Anteriorly and posteriorly these fibres constitute the palmar and dorsal inetrcarpal ligaments

Question 20

Describe the synovial cavity of the mcj

Answer 20

Is large and complex extending between the bones and may be interrupted by interosseous ligaments

Question 21

Ligaments associated with the mcj

Answer 21

Palmar intercarpal ligament is the largest
Dorsal intercarpal
Radial and ulnar collaterals

Question 22

Movements possible at the midcarpal joint

Answer 22

Flexion/ extension

Abduction/ adduction

Question 23

Which movement of flexion/ extension if freer at the mcj

Answer 23

Extension

opposite to the rcj

Question 24

ROMs of flexion/ extension of the mcj

Answer 24

Flexion 35d

Extension 50d

Question 25

Abduction/ adduction at the mcj is accompanied by what

Answer 25

Torsion between the 2 rows of bones

Question 26

ROM of ab/adduction at the mcj

Answer 26

Abduction 8d | Adduction 15d

Question 27

What is the principal structure responsible for maintaining the transverse arch of the 2 rows of carpal bones

Answer 27

The flexor retinaculum

Question 28

The rows of carpals + the flexor retinaculum form what important structure

Answer 28

The carpal tunnel

Question 29

What passes through the carpal tunnel

Answer 29

MEDIAN nerve | Tendons of flexor pollicis longus, flexor digitorum profundus, flexor digitorum superficialis

Question 30

A fall onto an outstretched hand may result in a dislocation where

Answer 30

Radiocarpal and/or midcarpal joints

Question 31

What is important about the movements occurring at the wrist

Answer 31

Movements occurring at the radiocarpal and midcarpal joints are happening at the same time so combine to give the wrist its full ROM

Question 32

What is the total range of flexion/ extension possible at the wrist

Answer 32

85d in each direction Flexion - 50d at rcj and 35 at mcj Extension - 35d at rcj and 50d at mcj

Question 33

Where does the axis of flexion/ extension of the wrist fall through

Answer 33

The head of the capitate

Question 34

When is flexion least effective and what limits this movement

Answer 34

Limited by tension in the extensor tendons and is greatly reduced if fingers are flexed I.e. wrist flexion is greatest when fingers are extended

Question 35

What are the total ROMs for ab/adduction at the wrist complex

Answer 35

Abduction - 15d | Adduction - 45d

Question 36

Muscles producing wrist flexion

Answer 36

Flexors carpi radialis and ulnaris Palmaris longus Flexor digitorum profundus/ superficialis Flexor pollicis longus

Question 37

Muscles producing wrist extension

Answer 37

``` Extensors carpi ulnaris and radialis longus and brevis Extensor digitorum Extensor indicis Extensor digiti minimi Extensor pollicis longus ```

Question 38

Muscles abducting the wrist

Answer 38

Flexor carpi radialis | Extensor carpi radialis longus and brevis

Question 39

Muscles adducting the wrist

Answer 39

Flexor carpi ulnaris | Extensor carpi ulnaris

Question 40

What happens at the wrist during flexion/ extension of the fingers

Answer 40

The carpal flexors/ extensors fix the wrist preventing loss of digital power n.b. grip is not as strong when wrist strongly extended or flexed

Question 41

Why is the wrist slightly extended when powerful grip is needed

Answer 41

This extension stretched the digit flexors allowing a powerful grip This is the position the wrist is fused in to allow the maintenance of grip power