Hand Flashcards
Describe the features of the skin of the hands and the impact that it has on its function
Thick, immobile, creased skin
Enables firm grip
What is the function of superficial fascia?
Binds skin to deep dascia
What are the functions of the deep fascia of the hands?
Forms flexor retinaculum.
Forms palmar apponeurosis.
Flexor sheaths of fingers
What are the muscles of the hand?
- Muscles of the thumb – **Thenar eminence **
- Muscles of the little finger – **Hypothenar eminence
- Lumbricals
- Interossei
What are the muscles of the thenar eminence?
- Abductor pollicis brevis
- Flexor pollicis brevis
- Opponens pollicis
- Adductor pollicis
Movements of the thumb
Origin of the abductor pollicis brevis?
(Thenar eminence)
Tubercle of scaphoid & trapezium & flexor retinaculum
Insertion of the abductor pollicis brevis?
Lateral side of base of proximal phalanx of the thumb
Nerve supply of abductor pollicis brevis?
Median Nerve
Action of abductor pollicis brevis?
Abduct the thumb
Origin of the flexor pollicis brevis
(Thenar emminence)
Superficial head: Tubercle of trapezium & flexor retinaculum
Deep head: Trapezoid & capitate bones
Insertion of the flexor pollicis brevis
Lateral side of base of proximal phalanx of the thumb
Nerve supply of flexor pollicis brevis
Median nerve
Action of flexor pollicis brevis
Flexes the thumb
Origin of opponens pollicis
(Thenar eminence)
Tubercle of trapezium & flexor retinaculum
Insertion of the opponens pollicis
Lateral half of palmar surface of the first metacarpal bone
Nerve supply of opponens pollicis
Median nerve
Action of opponens pollicis
Opposition of the thumb
Origins of the adductor pollicis
(Thenar eminence)
Oblique head: Capitate bone, bases of 2nd and 3rd metacarpal
Transverse head: Palmar aspect of 3rd metacarpal
Insertion of adductor pollicis
Lateral half of palmar surface of the first metacarpal bone
Nerve supply of adductor pollicis
Ulnar nerve
Action of the adductor pollicis
Adduction of the thumb
What are the muscles of the hypothenar eminence?
- Abductor digiti minimi
- Flexor digiti minimi
- Opponens digiti minimi
- Pamaris brevis
Origin of the abductor digiti minimi
(Hypothenar eminence)
Pisiform bone
Insertion of the abductor digiti minimi
Ulnar side of base of proximal phalanx of little finger
Nerve supply of the abductor digiti minimi
Ulnar nerve
Action of abductor digiti minimi
Abduction of the little finger
Origin of flexor digiti minimi
(Hypothenar eminence)
Hook of hamate, flexor retinaculum
Insertion of flexor digiti minimi
Ulnar side of base of proximal phalanx of little finger
Nerve supply of flexor digiti minimi
Ulnar nerve
Action of flexor digiti minimi
Flexion of little finger
Origin of opponens digiti minimi
(Hypothenar eminence)
Hook of hamate, flexor retinaculum
Insertion of opponens digiti minimi
Medial surface of shart of 5th metacarpal
Nerve supply of opponens digiti minimi
Ulnar nerve
Action of opponens digiti minimi
Laterally rotates little finger for opposition
Origin of palmaris brevis
(Hypothenar eminence)
Flexor retinaculum & palmar aponeurosis
Insertion of palmaris brevis
Skin along the medial border of hand
Nerve supply of palmaris brevis
Ulnar nerve
Action of palmaris nerve
Helps in gripping by making hypothenar eminence prominent
Origin of the lumbricals
Tendon of flexor digitorum profundus
Insertions of lumbricals
1st lumbrical: Insertion on 2nd MCP joint
2nd lumbrical: Insertion on 3rd MCP joint
3rd lumbrical: Insertion on 4th MCP joint
4th lumbrical: Insertion on 5th MCP joint
Nerve supply of lumbricals
1st & 2nd lumbricals – Median nerve
3rd & 4th lumbricals – Ulnar Nerve
What are the interossei muscles?
4 small muscles between the metacarpal bones
Origins of interossei muscles
1st, 2nd, 4th, 5th metacarpals
Insertions of interossei
Extensor expansions of 1st, 2nd, 4th, 5th fingers
Nerve supply of interossei
Ulnar Nerve
Action of the interossei
Adduct the thumb (1st), index (2nd), the ring (3rd) and little (4th) fingers towards the central axis which pass through the middle finger around which the other fingers move
Origin of the interossei
(All are bipennate)
Metacarpal bones
Insertion of the dorsal interossei
Extensor expansions of the 2nd, 3rd, 4th fingers
The middle finger has two
Nerve supply of the dorsal interossei
Ulnar nerve
Action of the dorsal interossei
Abduct the index (1st), middle (2nd, 3rd) & the ring (4th) fingers from the central axis which pass through the middle finger
What are the arteries of the hand?
Main arteries:
Ulnar artery
Radial artery
Branches:
Superficial branch
Radialis indicis and princeps pollicis
Ulnar artery pathway
Enters the hand superficial to flexor retinaculum on the radial side of pisiform bone
Divides into superficial and deep branches
Radial artery pathway
Appears in the palm between two heads of adductor pollicis and continues as deep arch
What is the superficial palmar arch?
Anastomosis between ulnar artery & superficial branch of radial artery
Located between the palmar aponeurosis and long flexor tendons
What are the branches of the superficial palmar arch?
3 palmar metacarpal arteries run in 2nd, 3rd and 4th spaces
What is the deep palmar arch?
Formed from radial artery & deep branch of ulnar artery
Arises in front of flexor retinaculum and terminal branch of radial artery
What are the branches of the deep palmar arch?
Palmar metacarpal arteries supplying lateral one and a half digits
What are the veins of the hand?
Dorsal venous network drains into cephalic vein laterally and basilic vein medially
Describe the pathway of the basalic vein
Runs medially, deep in the midarm
Along with brachial veins forms the axillary vein
Describe the pathway of the cephalic veins
Runs laterally in deltopectoral groove
Drains into axillary vein
