Wrist and Hand muscles (wk9) Flashcards
Hand muscle names and functions (muscle names indicate functions)
-Digitorum, Digiti minimi, Indicis, Pollicis, Carpi, Carpi Radialis, Carpi Ulnaris
-Digitorum-> Muscles move the fingers
-Digiti minimi -> Muscles move the little finger
-Indicis -> Muscles moves the index finger
-Pollicis -> Muscles moves the thumb
-Carpi -> Muscles move the wrist
-Carpi radialis -> Muscles cause radial deviation (abduction) of the wrist
-Carpi Ulnaris -> Muscles causes ulnar deviation (adduction) of the wrist
Full muscle names
-Extensor digitorum, Extensor indicis, Flexor pollicis longus, Extensor digiti minimi, Flexor carpi ulnaris, Extensor carpi radialis
-Extensor digitorum -> Extension of the fingers
-Extensor indicis -> Extension of the index finger
-Flexor pollicis longus -> Flexion of the thumb
-Extensor digiti minimi -> Extension of the little finger
-Flexor carpi radialis -> Flexes the wrist + Radial deviates the wrist
-Extensor carpi ulnaris -> Extends the wrist + Ulnar deviation of the wrist
Forearm flexors
-Lie on the anterior aspect of the forearm and flex the wrist and/ or digits (including the thumb)
-3 layers -> deep (2 muscles) , intermediate (1 muscle) and superficial (3 muscles)
-REMEMBER -> forearm=football, 2 deep muscles are defenders, 1 intermediate is a midfielder and the 3 superficial are strikers
Forearm flexor muscles
-Deep muscles
(flexorpollicis longus, flexor digitorum profundus)
- Flexor pollicis longus (thumb muscle) -> O: Anterior radius, I: Distal phalanx of thumb, F: Flexes the thumb
- Flexor digitorum profundus (finger muscles) -> O: Ulna, I: Distal phalanges of fingers, F: Flexes fingers
Forearm flexor muscles
-Intermediate muscles, Superficial muscles
(Flexor digitorum superficialis, Flexor carpi-radialis, Palmaris longus, Flexor carpi ulnaris)
- Flexor digitorum superficialis -> O: Medial epicondyle (common flexor tendon), I: Middle phalanges of fingers, F: Flexes fingers (but not distal interphalangeal joint). The superficialis tendon splits and the flexor digitorum profundus tendon runs through it.
-Superficial muscles:
1. Flexor carpi radialis -> O: Medial epicondyle (common flexor tendon), I: Base Metacarpal 2, F: Flexes wrist and radial deviation
2. Palmaris longus -> O: Medial epicondyle (common flexor tendon), I: Palmar fascia, F: Weak wrist flexor and anchor for skin and fascia of the hand
3. Flexor carpi ulnaris -> O: Medial epicondyle (common flexor tendon), i: Metacarpal 5 (also pisiform and hamate), F: Wrist flexion and ulnar deviation
Superficial forearm extensors
-Lie on the posterior aspect of the forearm and extend wrist and/or digits
-2 layers -> superficial (5 muscles) and deep layer (4 muscles)
Superficial forearm extensors
-Superficial muscles (Extensor carpi radialis longus, Extensor carpi radialis brevis, Extensor digitorum, Extensor digiti minimi, Extensor carpi ulnaris)
- Extensor carpi radialis longus -> O: Lateral epicondyle (common extensor tendon), I: Base metacarpal 2, F: Wrist extension and radial deviation
- Extensor carpi radialis brevis -> O: Lateral epicondyle (common extensor tendon), I: Base metacarpal 3, F: Wrist extension and radial deviation
- Extensor digitorum -> O: Lateral epicondyle (common extensor tendon), I: Dorsal digital expansion (known as the extensor hood and is a fibrous extension of extensor digitorum tendons on back of fingers), F: Extend fingers
- Extensor digiti minimi -> O: Lateral epicondyle (common extensor tendon), I: Dorsal digital expansion, F: Extends little finger
- Extensor carpi ulnaris -> O: Lateral epicondyle (common extensor tendon), I: Base metacarpal 5, F: Wrist extension and ulnar deviation
Superficial forearm extensors
-Deep muscles (Extensor indicis, Extensor pollicis longus, Extensor pollicis brevis, Abductor pollicis longus
- Extensor indicis -> O: Posterior surface of distal surface of ulna , I: Dorsal digital expansion, F: Extends index finger
- Extensor pollicis longus -> O: Posterior surface of ulna, I: Distal phalanx, F: Extends thumb
- Extensor pollicis brevis -> O: Posterior surface of radius, I: Proximal phalanx, F: Extends the thumb but not interphalangeal joint
- Abductor pollicis longus -> O: Posterior surface of ulna and radius, I: Base metacarpal 1, F: Abducts thumb and extends the thumb + only carpometacarpal joint (CMC)
Superficial forearm extensors
-Anatomical snuffbox
-Includes the Extensor Pollicis Longus, Extensor Pollicis Brevis and Abductor Pollicis Longus
Intrinsic hand muscles
-Includes Thenar eminence and Hypothenar eminence
-The intrinsic muscles of the hand allow us to do fine and precise movements of the hand and fingers (digits). The extrinsic muscles allow us to get greater power in our hands so we use this to do movements such as gripping.
* Thenar eminence -> Fleshy bit of the hand at the base of the thumb. 3 muscles are involved and can move the thumb. Movements involved are: flexion (thumb coming across hand), abduction (thumb moving away from hand), opposition (thumb coming round in more circular motion towards other side of the hand)
* Hypothenar eminence -> Fleshy bit of the hand at the base of the little finger. 3 muscles are involved and can move the little finger. -> Movements involved are: flexion (little finger coming across hand), abduction (little finger moving away from hand), opposition (little finger coming round in more circular motion towards the other side of the hand)
Intrinsic hand muscles
-Opponens pollics muscle and Opponens digiti minimi
-Opposition movement for thumb and little finger to meet is through the Opponens pollicis muscle (thumb side) and the Opponens digiti minimi muscle of hand (little finger side)
Intrinsic hand muscles
-Flexor muscles
-Flexor muscles -> Flexor pollicis brevis muscle (thumb side) and Flexor digiti minimi muscle of hand (little finger side)
Intrinsic hand muscles
-Abductors
-Abductors -> Abductor pollicis brevis muscle (thumb side) and Abductor digiti minimi muscle of hand (little finger side)
Intrinsic hand muscles:
-Demonstrate abduction and adduction of the fingers and name the muscles which produce this action
- Abduction -> Interosseous (palmar and dorsal side) -> Dorsal is abducting
- Adduction -> Interosseous (palmar and dorsal side) -> Palmar is adducting
Intrinsic hand muscles:
-Palmar interosseous muscles (located on the side of the finger towards the middle finger + lumbricals:
- First palmar interosseous muscle
- Second palmar interosseous muscle
- Third palmar interosseous muscle
-The lumbricals are more superficial to the interosseus on the palmar aspect of our hand. The lumbricals link the flexor and extensor tendons of our hand. They allow flexion at the metacarpal joints whilst extending up the interphalangeal joints.
