Topic 4: BONES AND JOINTS OF THE WRIST AND HAND Flashcards
Which bones make up the “wrist joint complex”?
- carpal bones
- radius
- ulna
Which bones does the radius articulate with?
the proximal carpal bones
What does the ulna articulate with?
doesnt directly articulate with carpals
Order of carpal bones
Some, Lovers, Try, Positions, THat, THey, Cant, Handle
scaphoid, lunate, triquetrum, pisiform
Trapezium, trapezoid, capitate, hamate
2 joints of the wrist complex
- Radiocarpal
2. Mid carpal
Articular surfaces of the radiocarpal jt
- scaphoid, lunate, triquetrum
- distal surface of radius
- distal surface of Inf RU jt disc
Articular surfaces of the Midcarpal jt
- scaphoid, lunate, triquetrum
- trapezium, trapezoid, capitate, hamate
(between the 2 rows of the carpals)
Classification of the radiocarpal joint
synovial, biaxial, ellipsoid
Movements of the radiocarpal jt
- flexion - extension (palmarflexion- dorsiflexion)
- transverse axis - abduction - adduction (radial deviation- ulnar deviation)
- anteropostierior axis
Articular surfaces of the Radiocarpal jt
- distal surface of scaphoid, lunate, triquetrum
2. proximal surface of radius & of inferior RU disc
Where does the articular capsule of the RC jt attach?
to the articular margins of the bones involved
What is the RC jt capsule reinforced by?
by capsular ligaments at sides and anteriorly & posteriorly
Synovial membrane of the RC jt
- usually restricted to RC jt space
- sometimes communicates with synovial cavity of the inf RU jt
What is the Triangular Fibrocartilage Complex?
Ligamentous & cartilaginous complex of structures
What are the components of the TFCC?
- triangular fibrocartilage (articular disc)
2. ligaments
Ligaments of the TFCC
ulnotriquetral, ulnolunate, palmar and
dorsal radioulnar ligaments, ulnar collateral
ligament
Functions of the TFCC:
- stabilizes distal radioulnar and ulnocarpal joints
- transmits & distributes loads from carpals to ulna
- helps facilitate complex movements of the wrist
How is the TFCC commonly injured (lateral)
by acute/ repetitive loading in an extending wrist position (FOOSH)
Ligaments of the RC jt
- collaterals
2. dorsal & palmar radiocarpal
Radial collateral ligament of the wrist limits:
adduction
Ulnar collateral ligament of the wrist limits:
abduction
Fibres of the dorsal & palmar radiocarpal ligaments
- run inferiorly & medially –> ensure that carpals move with the radius and ulna during pronation & supination
Dorsal radiocarpal ligament of the wrist limits:
flexion
Palmar radiocarpal ligament of the wrist limits:
extension
Midcarpal joint classification
synovial, biaxial, condyloid
midcarpal joint movements
- flexion - extension (palmarflexion - dorsiflexion)
- -> transverse axis - abduction - adduction (radial deviation - ulnar deviation)
- -> anteroposterior axis
Articular surfaces of the MC joint
- distal surface of scaphoid, lunate, triquetrum
2. proximal surface of trapezium, trapezoid, capitate, hamate
What does the articular capsule of the MC joint attach to?
the articular margins of the bones