Upper limb gross anatomy 4: The hand Flashcards
What mnemonic can be used to remember the carpal bones?
Some Scaphoid Lovers Lunate Try Triquetral Positions Pisiform They Trapezium Cannot Capitate Handle Hamate
Where are the carpometacarpal joints?
Between the carpal and metacarpal bones.
Which carpal bones are involved in the first carpometacarpal joint and what shape is the joint?
Trapezium and first metacarpal. Saddle-shaped joint.
Describe the movements that the thumb is capable of making.
Abduction Adduction Extension Flexion Opposition Reposition
What is the function of the palmar aponeuronsis?
- Extended tendon of the palmaris longus
- Forms four digital bands that radiate from the apex and attach distally to the bases of the proximal phalanges.
- Part of deep fascia of the palm
What are the muscles of the hypothenar eminences?
Abductor digiti minimi
Flexor digiti minimi brevis
Opponens digiti
What are the attachments of abductor digiti minimi?
Proximal - pisiform
Distal - medial side of base of 5th proximal phalanx
What is the innervation to the abductor digiti minimi?
Deep branch of ulnar nerve (C8&T1)
What is the main action of abductor digiti minimi?
Abduct 5th digit, assists in flexion of its proximal phalanx.
What are the attachments of flexor digiti minimi brevis?
Proximal - hook of hamate and flexor renitaculum
Distal - medial side of base of 5th proximal phalanx
What is the innervation to the flexor digiti minimi brevis?
Deep branch of ulnar nerve (C8&T1)
What are the actions of flexor digiti minimi brevis?
Flexes proximal phalanx of 5th digit
What are the attachments of opponens digiti?
Proximal - hook of hamate and flexor renitaculum
Distal - medial border of 5th metacarpal
What is the innervation to opponens digiti?
Deep branch of ulnar nerve (C8&T1)
What are the actions of opponens digiti?
Draws 5th metacarpal anteriorly and rotates it, bringing 5th digit into opposition with thumb.
What are the muscles of the thenar eminences?
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
Adductor pollicis
What are the attachments of opponens pollicis?
Proximal - flexor retinaculum and tubercles of scaphoid and trapezium
Distal - Lateral side of base of proximal phalanx of thumb
What is the innervation to opponens pollicis?
Recurrent branch of ulnar nerve (C8, T1)
What are the actions of opponens pollicis?
To oppose the thumb - draws 1st metacarpal medially to the centre of the palm and rotates it medially.
What are the attachments of abductor pollicis brevis?
Proximal: flexor retinaculum and tubercles of scaphoid and trapezium
Distal: Lateral side of base of proximal phalanx of thumb
What is the innervation to the abductor pollicis brevis?
Recurrent branch of ulnar nerve (C8, T1)
What is the action of abductor pollicis brevis?
Abducts thumb and helps oppose.
What are the attachments of flexor pollicis brevis?
Proximal: flexor retinaculum and tubercles of scaphoid and trapezium
Distal: Lateral side of base of proximal phalanx of thumb
What is the innervation to flexor pollicis brevis?
Superficial head - recurrent branch of ulnar nerve (C8, T1)
Deep head - deep branch of ulnar nerve (C8,T1)
What is the action of flexor pollicis brevis?
Flexes thumb.
What are the attachments of the oblique head of adductor pollicis?
Proximal - base of the 2nd and 3rd metacarpals, capitate and adjacent carpals
Distal - medial side of base of proximal phalanx
What are the attachments of the transverse head of adductor pollicis?
Proximal - anterior surface of shaft of 3rd metacarpal
Distal - medial side of base of proximal phalanx
What is the innervation to adductor pollicis?
Deep branch of ulnar nerve (C8,T1)
What are the actions of adductor pollicis?
Adducts thumb towards lateral border of palm.
What movements are possible at the 1st carpometacarpal joint?
- Abduction and adduction occur around the antero-posterior axis
- Flexion and extension occur around the lateral axis
What movements are possible at the 1st carpometacarpal joint?
- Flexion/extension
- Supinatory rotation 10-15 degrees
- Abduction/adduction
What is the nerve supply to the muscles of the hypothenar eminence?
Deep branch of ulnar nerve (C8, T1)
Why is the ulnar nerve clinically important?
Supplies motor innervation to opponens pollicis, abductor pollicis and superficial part of flexor pollicis brevis.
Very superficial to the palm - prone to damage if the wrist/hand is cut.
What is the nerve supply to adductor pollicis?
Deep branch of ulnar nerve (C8, T1)
What are the attachments of the 1st lumbrical?
Origin - radial side of the most radial tendon of flexor digitorum profundus
Insertion - extensor near the metacarpophalangeal joint of the index finger
What are the attachments of the 2nd lumbrical?
Origin - radial side of 2nd most radial tendon of flexor digitorum profundus of the middle finger
Insertion - extensor near the metacarpophalangeal joint of the middle finger
What are the attachments of the 3rd lumbrical?
Origin - one head on radial side of flexor digitorum profudus of ring finger, the other on the ulnar side of tendon of the middle finger.
Insertion - Exstensor expansion of ring finger
What are the attachments of the 4th lumbrical?
Origin - one head the radial side of flexor digitorum profundus of the little finger, the other on ulnar side of ring finger
Insertion - radial side of little finger, inserts on extensor expansion
What are the actions of the lumbricals?
They flex the fingers at the metacarpophalageal joints and extend the interphalangeal joints.
What is the nerve supply to the lumbricals?
1st&2nd - median nerve
3rd&4th - deep branch of ulnar nerve
Which muscle abducts digit 5?
Abductor digiti minimi
Which muscle adduct and abducts digit 1?
Abductor pollicis brevi, adductor pollicis
Where do the digital branches originate?
Common digital branches originate from the superficial palmar arch. Proper palmar digital arteries arise from the common.
