Hand Flashcards
deep and superficial transverse metacarpal ligaments
connect the heads on the metacarpals at the MP joints
restrict the movement of the bones relative to each other
scaphoid fracture: mechanism and risks
FOOSH
waist of scaphoid can fracture
blood supply from distal to proximal from radial artery, if fractured proximal portion loses blood supply
palmar radiocarpal ligament
distal radius and scaphoid, lunate, triquetrum
palmar aspect
radial collateral ligament
radial styloid process to scaphoid
limit ulnar deviation
ulnar collateral ligament
ulnar styloid process to triquetrum and pisiform
limit radial deviation
dorsal radiocarpal ligament
distal radius to scaphoid, lunate, triquetrum
dorsal aspect
distal radioulnar ligament
palmar and dorsal
wraps around distal ulna to connect to radius
flexor retinaculum
aka transverse carpal ligament
attach to pisiform, hook of hamate; scaphoid, trapezium
covers carpal tunnel
extensor retinaculum
radius, pisiform, triquetrum
hold extensor tendons in place
can be removed to use as a surgical graft
palmar aponeurosis
from flexor retinaculum and palmaris longus
insert base of MP joint into transverse metacarpal ligament
muscle attachment, grip, protect deep tendons
carpal tunnel
made by flexor retinaculum and deep arch of carpal bones
contains tendons of: flexor digitorum profundis, flexor pollicis longus, flexor digitorum superficialis, median nerve
carpal tunnel syndrome
entrapment of median nerve within carpal tunnel
numbness, tingling, pain in hand and forearm
pregnancy, work, systemic health
fibrous digital sheath
cruciate, annular ligaments and distal extensions of palmar aponeurosis
sheaths continuous with carpal tunnel to hold tendons to bony plane and prevent bowing
extensor hoods
tendons of ext digitorum and extensor pollicis longus form these on proximal phalanges
attachments for many intrinsic muscles
allow MP joint to flex while extending IP joints
What muscles of the forearm or hand are involved in a power grip? precision?
power: forearm, extrinsic hand muscles
precision: hand, intrinsic hand muscles
palmaris brevis
origin: flexor retinaculum
insertion: dermis on ulnar border
innervation: ulnar n
action: wrinkle skin on side of palm
adductor pollicis
oblique head and transverse head
origin: oblique, 2 and 3 metacarpals and capitate
transverse:3rd metacarpal
insertion: proximal 1st phalanx
innervation: ulnar n
action: adduction of thumb
lumbricals
origin:
1 and 2: lateral tendons of flex dig profundus
3 and 4: medial tendons of flex dig profundus
insertion: lateral side dorsal expansion 2-5
innervation: 1-2 median, 3-4 ulnar
action: flex MCP, extend DIP PIP
dorsal interossei
origin: adjacent side of metacarpals (lateral to midline, middle finger, so they can abduct, not pinky or thumb)
insertion: dorsal expansion, base of 2-4 proximal phalanges
innervation: ulnar
action: abduct digits, flex MP, extend IP
palmar interossei
origin: palmar surface 2, 4, 5 metacarpals
insertion: dorsal expansion, base of 2, 4, 5 proximal phalange
innervation: ulnar
action: adduct digit to center of hand, flex MP, extend IP
none on 3rd digit bc midline of hand
flexor pollicis brevis
origin: deep - trapezium, flexor retinaculum; superficial - trapezoid, capitate
insertion: proximal phalange 1st digit
innervation: median
action: flex thumb
opponens pollicis
origin: trapezium and flexor retinaculum
insertion: lateral side first metacarpal
innervation: median
action: bring 1st digit to center of palm
abductor pollicis brevis
origin: flexor retinaculum, scaphoid, trapezium
insertion: proximal 1st phalanx
innervation: median
action: abduct thumb
opponens digiti minimi
origin: hook of hamate, flexor retinaculum
insertion: 5th metacarpal
innervation: ulnar
action: lateral rotation of 5th metacarpal to center of palm (opposition)
