
The Wrist and Hand Great Mobility = Many Joints
Joints You know the bones…
The Wrist • Radiocarpal • wrist joint • condyloidjoint • Carpals • two rows of four bones • carpal joints • gliding joints
The Hand Metacarpals carpometacarpal joint intermetacarpal joints metacarpal-phalangeal joints interphalangeal joints
Ligaments of the wrist(radiocarpal joint) • volar (palmar) radiocarpal • volar (palmar) ulnarcarpal • ulnar collateral • dorsal radiocarpal • dorsal ulnarcarpal • radial collateral
Movements of theHand at the Wrist Joint • Flexion • Extension • Hyperextension • Radial flexion (abduction) • Ulnarflexion (adduction) • Circumduction
Carpal Tunnel • finger flexors and median nerve pass through it • overuse my result in pain caused by nerve compression and numbing of the fingers caused by blood vessel involvement.
Movements of the Thumb(saddle joint) • Abduction • Adduction • Flexion • Extension • Circumduction • Opposition
Movements of the Fingers(Hinge joints) • Flexion • Extension • Abduction • Adduction • Circumduction
Muscles Of the wrist and hand
Muscles of theHand • Of the 19 muscles that move the fingers and thumb • 10 are located entirely in the hand – called intrinsics • Those located outside the hand on the forearm but with tendon attachments on the thumb or fingers are extrinsic muscles
Naming muscles • Digitorium • fingers • Superficialis • Superficial or outermost • Pollicis • thumb • Palmus • palm • Digit minimi • Little finger • Indicis • Index finger • Brevis • short • Longus • long
Intrinsic Muscles • Opponenspollicis- flexion • Abductor pollicisbrevis- abduction • Flexor pollicisbrevis- flexion • Oponens digit minimi- opposition • Abductor digit minimi- abduction • Flexor digit minimibrevis- circumduction of thumb • Adductor pollicis- adduction • Palmarinterosseus- adduction • Dorsal interosseus- abduction • Lumbrical Thenareminance: Move thumb; circumduction Hypothenar eminance grasping
Muscles of the Wrist • Wrist Flexors (proximal attachment) – medial epicondyle
Muscles of the Wrist and Hand • Wrist Extensors (proximal attachment) – lateral epicondyle • These attachments allow these muscles to remain effective across the wrist joint regardless of the position of the forearm – they also contribute to the stabilization of the elbow • Disadvantage is the limiting ROM when there is simultaneous movement across all joints
Flexors/Extensors of Wrist and Hand* flexors extensors • Flex. Digitoriumprofundus* • Flex. Pollicislongus* • Flex. Digitoriumsuperficialis* • Flex. Carpi ulnaris • Palmaris longus • Flex. Carpi radialis • Ext. indicis* • Ext. pollicislongus* • Ext. pollicisbrevis* • Ext. carpiulnaris • Ext. digitiminimi* • Ext. digitorum* • Ext. carpiradialislongus • Ext. carpiradialisbrevis
Other cool stuff How it all works
Cooperative Action of theWrist and Digits • The length of the long finger muscles is relative to the ROM in the wrist and fingers • Long finger muscles do not have sufficient length to permit the full range of motion in the joints of the fingers and wrist at the same time. • Try and flex the wrist and fingers at the same time • Try and extend the wrist and fingers at the same time
Using the Hands for Grasping (Prehension) • Power grip • flexion of all fingers • thumb being primarily a stabilizer • palm is not involved • depends on size and shape of object • uses more extrinsic muscles
Precision handling – involves the use of the thumb and one or two fingers in various positions in order to accommodate a variety of grasping functions • great variability in pressure and fine motor control • more intrinsic muscles being used