The hand Flashcards
Dorsal Interossei
Origin:
1: 1st metacarpal (medially) and 2nd metacarpal laterally
2: 2nd metacarpal (medially) and 3rd metacarpal laterally
3: 3rd metacarpal medially and 4th metacarpal laterally
4: 4th metacarpal medially and 5th metacarpal lateral
Insertion:
1. proximal phalanges of 2-4 (2nd=lateral, 3=medial and lateral, 4-medial)
Action:
1. MCP abduction of fingers 2,3,4 (dab)
Innervation:
1. ulnar nerve C8,T1
Palmar Interossei
Origin:
1. Medial 1st metacarpal
2. Medial 2nd metacarpal
3. Lateral 4th metacarpal
4. lateral 5th metacarpal
Insertion:
1. Medial 1st proximal phalanx
2. medial 2nd proximal phalanx
3. Lateral 4th proximal phalanx
4. Lateral 5th proximal phalanx
action:
1. adduct fingers 1,2,4,5
Innervation:
1. ulnar nerve C8,T1
Opponens Pollicis
origin:
1. tubercle of trapezium and flexor retinaculum
Insertion:
1. 1st metacarpal
Action:
1. medially rotates thumb
Innervation:
1. recurrent branch median nerve C8,T1
Abductor Pollicis Brevis
origin:
1. tubercle of scaphoid and trapezium, flexor retinaculum
Insertion:
1. proximal phalanx, extensor hood of thumb
Action:
1. abduct the thumb MCP joint
Innervation:
1. recurrent branch median nerve C8,T1
Flexor Pollicis Brevis
origin:
1. tubercule of trapezium, flexor retinaculum
Insertion:
proximal phalanx of thumb
Action:
1. flexes thumb MCP joint
Innervation:
1. recurrent branch median nerve C8,T1
abductor Digiti Minimi
Origin:
1. pisiform, pisohamate ligament, tendon of FCU
Insertion:
1. proximal phalanx of little finger
Action:
1. abducts 5th finger MCP joint
innervation:
1. deep branch ulnar nerve C8,T1
Flexor Digiti Minimi Brevis
Origin:
1. hook of hamate, flexor retinaculum
Insertion:
1. proximal phalanx of little finger
Action:
1. flexes 5th finger MCP joint
innervation:
1. deep branch ulnar nerve C8,T1
Opponens Digiti Minimi
Origin:
1. hook of hamate, flexor retinaculum
Insertion:
1. 5th metacarpal
Action:
1. laterally rotates 5th metacarpal
innervation:
1. deep branch ulnar nerve C8,T1
Lumbricals of the hand
origin:
1. tendons of flexor digitorum profundus
Insertion:
1. extensor hood
Action:
1. flex MCP joints
2. extend IP joint lumbrical position
Innervation:
1. 1st and 2nd (laterally) = median nerve
2. 3rd and 4th (medially) =deep branch ulnar
Adductor Pollicis
origin:
1. transverse head: 3rd metacarpal
2. oblique head: capitate and bases of 2nd and 3d metacarpals
Insertion:
1. base of proximal phalanx of thumb
action:
1. adducts the thumb
Innervation:
1. ulnar never (deep branch) C8,T1
Blood supply into the hand
- radial artery
- ulnar artery
Radial artery
- enters deep into palm to form deep palmar arch
- supplies thumb and lateral index finger
Ulnar Artery
- forms superficial palmar arch
- supplies medial index finger and fingers 3-5
Nerves of the hand
- Median nerve
- radial nerve
- ulnar nerve
What does the median nerve supply
- motor- thenar muscles and lateral 2 lumbricals
- sensory: thumb, index, middle and 1/2 ringfinger
Median nerve entrapment
location, cases, clinical findings
- Location: in the carpal tunnel under transverse carpal ligament
Causes:
- sprains
- wrist fx
- arthritis
- ganglion cysts
Clinical findings:
- numbness or pain in wrist/hands/fingers
- tingling, difficulty with fine motor movements
Radial Nerve (superficial branch)
supplies
- sensory only
- dorsal lateral palm, dorsal aspect of finges 1-3 and the lateral 1/2 of the ring finger
Radial nerve entrapment at the hand
location, causes, clinical findings
Location:
- wartenberg’s syndrome
- between brachioradialis and ECRL
Clinical findings:
- pain over distal radial forearm and paresthesia over dorsal radial hand
Causes:
- trauma
- stretch injury
Ulnar Nerve Supplies
Sensory:
- medial dorsal and palmar aspect of the hand, 5th digit and medial half of 4th digit
Motor:
- all intrinscis EXCEPT 2 lateral lumbricals and thenar muscles
Ulnar nerve Entrapment
location, causes, clinical findings
Location
- tunnel of Guyon
Causes
- ganglion cysts
- trauma
- repetitive wrist movements
- arthritis
- wrist fx
Clinical findings
- wrist pain
- numbeness/tingling in pinky and ring fingers
- weakness in pal of hand and thumb
- difficulty with grip
Review Laceration zones
review picture
MRI medical imaging in the hand
- MRI is the most important imaging that takes place when lacerations of the hand occur, due to the ability to view the integrity of the tendons within the hand.
X-ray at the hand
- Depending on how a laceration occurs,
- possible through a crushing accident,
- an Xray may be required to assess bone integrity and see if there are any loose bodies within the hand.
Ultrasound at the hand
- bedside US in ED
- takes less time to preform than traditional wound exploration techniques or MRI
