Hand Flashcards
Abductor Digiti Minimi
(most lateral)
O: Pisiform Bone & tendon of flexor carpi ulnaris
I: base of PROXIMAL phalanx of little finger (5th digit)
A: Abduction of pinky
N: Ulnar N. (deep branch)
Flexor Digiti Minimi Brevis
(medial) O: Flexor Retinaculum, hook of hamate I: base of Proximal Phalanx (same as abductor) A: Flexion of proximal phalanx of pinky N: Ulnar N. (deep branch)
Opponens Digiti Minimi
(found under the abductor digit minimi) O: Flexor Retinaculum & hook of hamate I: palmar surface of 5th metacarpal A: Opposition of the little finger (draws pinky anteriorly + rotates to face thumb) N: MEDIAN N.
Abductor Pollicis Brevis
(most lateral) O: Flexor retinaculum, tubercles of SCAPHOID and Trapezium I: base of proximal phalanx of thumb A: abducts thumb N: Median Nerve (recurrent branch)
1/2 LOAF
MEDIAN nerve innervates the 1st and 2nd lumbricals and the opponent pollicis, abductor pollicis brevis, and flexor pollicis brevis
(the rest of the intrinsic muscles of the hand = ULNAR N. _
Flexor Pollicis Brevis
(medial) O:Flexor Retinaculum, tubercle of TRAPEZIUM I: base of proximal phalanx of thumb A: Flexion of Proximal phalanx of thumb N: Median N (recurrent branch)
Opponens Pollicis
(underneath the abductor pollicis brevis)
O: flexor retinaculum and tubercle of trapezium [ same as flexor p.brevis]
I: 1st metacarpal**
A: draws thumb forward and rotates medially
N: Median N. (recurrent branch)
ADDuctor Pollicis
has 2 heads - oblique and transverse
O: oblique: bases of 2nd 3rd metacarpals +capitate
transverse: surface of 3rd metacarpal (middle f.)
I: base of proximal phalanx (medial side)
A: adducts thumb
N: Ulnar Nerve**
Dorsal Interossei
DABS (4 of them)
O: on both sides of metacarpal bones
I: base of proximal phalanges, EXTENSOR EXPANSION HOOD of fingers 2-4
A: Abducts fingers AWAY from midline
-flex at MCP joints, extend at DIP and PIP
N: Ulnar N. (deep branch)
Palmar Interossei
PAD (only 3 - on 2, 4, 5)
O: Sides of metacarpals 2, 4, 5
I: extensor expansion hood and base of proximal phalanx
A: ADDuct fingers 2,4,5 TO midline
-flex at MCP joints, extend at DIP and PIP
N: Ulnar N. (deep branch)
Palmaris Brevis
(rarely seen, unimportant)
Superficial branch of Ulnar nerve innervates
1st and 2nd Lumbricals
O: lateral 2 tendons of flexor digitorum profundus
I: Extensor Expansion HOOD of digits 2, 3
A: flex at MCP (metacarpal) joints, extend at DIP and PIP (distal and proximal)
N: Median N. (digital branches)
3rd and 4th Lumbricals
O: medial 3 tendons of flexor digitorum profundus
I: Extensor Expansion HOOD of digits 4, 5
A: flex at MCP joints, extend at DIP and PIP
N: Ulnar N. (deep branch)
Name the carpal bones
So Long To Pinky, Here Comes The Thumb
Scaphoid (most often fractured) Lunate (most dislocated) Triquetrum Pisiform Hamate Capitate Trapezoid Trapezium
Superficialis Splits in two,
To Permit Profundus Passing through.
Superficialis Digitorum splits and Profundus continues to the Distal Phalanx
Why is Brachioradialis such an odd muscle?
Function: Its the Beer Raising muscle, flexes elbow, strongest
when wrist is oriented like holding a beer.
Innervation: Breaks Rule: it’s a flexor muscle, But Radial.
Important relation: Behind it is the Radial nerve in the cubital
fossa.
Attachment: Attaches to Bottom of Radius.
Cubital fossa contents “N-MAN”:
From lateral to medial: Nerve Muscle Artery Nerve 1. radial Nerve 2. biceps Muscle tendon, 3. brachial Artery 4. median Nerve.
Where does the extensor retinaculum attach?
Laterally to radius, medially to pisiform and triquetrum
Where does the flexor retinaculum attach?
Laterally - hook of hamate and pisiform
Medially - scaphoid tubercle and ridge of trapezium
What are the 10 components that pass through the transverse carpal ligament (flexor retinaculum)
- Flexor Digitorum Superficialis (4)
- Flexor Digitorum Profundus (4)
- Flexor Pollicis Longus (1)
- MEDIAN Nerve
(flexor carpi radialis lies superficial)
What are the causes and results of Carpal Tunnel Syndrome?
Causes: excessive exercise, infection, fluid retention
Symptoms: thenar wasting, paresthesia(tingling)/hypoesthesia/anesthesia of lateral 3 1/2 fingers
** ADDUCTION is spared (since innervated by ulnar nerve)
What are the components of the extensor expansion hood?
- Lumbricals
- Interossei (PAD/DABS)
- Extensor Digitorum**
The common palmar digital arteries pass between what? The proper palmar digital arteries?
- Metacarpals
- either sides of digits 2-5
Which artery becomes the superficial palmar arch?
Ulnar Artery
The deep branch of the ulnar artery passes between what two muscles?
- abductor digiti minimi
2. flexor digiti minimi
The deep palmar arch is formed by which artery?
Radial Artery
USRD
The radial artery supplies blood vessels for the 1st and 2nd digits. What are these vessels called?
The Radial artery passes between 2 dorsal interossei** then becomes: PRINCEPS Pollicis (medial side of thumb ) & Radialis Indicis (lateral side of 2nd digit)
The palmar cutaneous branch provides sensation to the skin of the central palm from the ______ nerve.
Median
(ulnar N. to the medial side of the palm)
What nerve is responsible for the common palmar digital nerves and then the proper palmar digital nerves?
Ulnar Nerve (superficial branch)
Name the six muscles innervated by the Deep Branch of the Ulnar Nerve:
- Palmaris Brevis
- Hypothenar
- 3rd and 4th Lumbricals
- Dorsal Interossei
- Palmar Interossei
- Adductor Pollicis Muscles
Which nerve is ONLY cutaneous in the hand?
Radial Nerve
Claw Hand is due to ______ nerve palsy. What are some of the symptoms?
ULNAR nerve palsy
- Weakness in most intrinsic hand muscles (especially lumbricals 3 and 4)
- unopposed activity of extensor digitorum
- hyperextension of 4th and 5th MCP jnt.
- flexion of PIP and DIP
- lose ability to spread fingers –> interossei
Ape Hand is due to _____ nerve palsy. What are the symptoms?
MEDIAN nerve palsy
- wasting of thenar muscles
- inability to oppose/abduct thumb
(lose of million dollar nerve)
Hand of benedictine is due to proximal injuries of what nerve? What are some Symptoms?
Median Nerve
- no flexion of MCP at digits 2-3
- no flexion/extension PIP and DIP
(due to loss of innervation of 2 LUMBRICALS)
+ lateral half of flexor digitorum profundus
- extensor digitorum is unopposed (fingers 2 and 3 can’t make a fist)
Wrist Drop is due to an injury where and to which nerve?
Proximal injury at or below the elbow
- damages the RADIAL nerve
- loss of wrist extensor innervation in forearm
What causes Dupuytren’s Contracture?
Fibrosus of Aponeurosis – results in flexion at MCP (can’t extend after***)
What is the function of the synovial sheath?
Allows the tendons to slide past one another
