Week3Anatomy Flashcards
bones of the proximal row (hand)
(radial to ulnar, in palmar view) scaphoid lunate triquetrum pisiform
bones of the distal row (hand)
(radial to ulnar, palmer view) Trapezium Trapezoid Capitate Hamate
How many carpal bones are there?
8
-total of proximal and distal rows
How many metacarpals are there?
5
How many phalanges are there
14
- each finger has proximal phalanx (PP), medial phalanx (MP), & distal phalanx (DP)
- EXCEPT thumb [or P1] is missing MP
Name the 3 joints of the phalange
- metacarpophalangeal joint (MP)
- Proximal interphalangeal joint (PIP)
- Distal interphalangeal joint (DIP)
Palmar aponeurosis
thickened area of deep fascia into which the palmaris longus attaches
transverse carpal ligament
under palmarcarpal ligament [is palmar aponeurosis same thing??]
- dense, tough band of connective tissue continuous with the antebrachial fascia.
- extends from the pisiform and hamate medially to the scaphoid and trapezium laterally
- ***forming the carpal tunnel
Dupuyten contracture
shortening, thickening, & fibrosis of palmar fascia 7 aponeurosis
Which tendons & nerve(s) pass through the carpal tunnel?
9 tendons: - 4 from flexor digitorum superficialis -4 from flexor digitorum profundus -1 from flexor pollicus longus 1 nerve: median nerve
how do you test for carpal tunnel syndrome?
Phalens manuever:
hold pt’s wrists in acute flexion (back to back like upside down prayer) for 30 -60 secs
-If numbness and tingling develop over the distribution of the median nerve (palmar surface of the thumb, and index, middle, and part of the ring fingers), the sign is positive
Thenar muscles
(Thenar think thumb side) 3 muscles: -abductor pollicis brevis -opponens pollicis -flexor pollicis brevis N: recurrent branch of the median nerve
recurrent branch of the median nerve
In: thenar muscles
Hypothenar muscles
(pinky side) 3 muscles: Abductor digiti minimi Opponens digiti minimi Flexor digiti minimi brevis N: ulnar nerve
dorsal branch of the ulnar nerve
- becomes superficial in the distal forearm
- receives cutaneous sensory information from the ulnar side of the dorsal hand and one and one-half digits.
Deep Ulnar nerve
supplies motor fibers to the: hypothenar muscles lumbricals for the fourth and fifth digits all of the interossei muscles adductor pollicis muscle
superficial ulnar nerve
supplies cutaneous sensory fibers to one and one-half digits
Ulnar Canal Syndrome
aka Guyon tunnel syndrome
-hypoesthesia of the medial one and one-half fingers and weakness of intrinsic hand muscles
superficial palmar arterial arch
-found immediately beneath the palmar aponeurosis. –major contributor to the arch is the ulnar artery
ulnar artery
- passes lateral to the pisiform bone along with the ulnar nerve to enter the palm of the hand.
- gives rise to the common palmar digital arteries and then near the web of the digits gives rise to the proper palmar digital arteries that continue distally to the finger tips
common palmar digital arteries
stem from superficial palmar arterial arch (ulnar artery)
- 4 of them?
- from palm to finger branching sites
proper palmar digital arteries
continue distally to the finger tips (1 on either side of finger) from common palmar digital arteries
fibrous digital sheaths
- hold tendons of the flexor digitorum superficialis and profundus in place over the digits
- inside fibrous sheaths are the synovial digital sheaths
synovial digital sheaths
lay inside fibrous digital sheaths
where does tendon of flexor pollicus longus terminate?
base of DP of thumb
where does tendon of flexor digitorum superficialis terminate?
- go to all 4 fingers
- split over the body of the proximal phalanx and inserts into the base of the middle phalanx.
Where do the tendons of flexor digitorum profundus terminate?
- goes to all 4 digits
- pass through the split in the tendons of the flexor digitorum superficialis and continue distally to insert into the base of the distal phalanx
Vincula
- are connective tissue bundles that extend from the tendons of the flexor digitorum muscle to the periosteum of the bone
- thought to carry a blood supply from the bone to the tendons
Lumbrical muscles
O: from the deep extensor tendons
I: tendons pass on the radial side of the metacarpal-phalangeal joint (MP joint) to insert into the extensor hood.
N: Lumbricals 1 and 2 are innervated by the median nerve
-lumbricals 3 and 4 are innervated by the ulnar nerve.
Fxn: The lumbricals flex the MP joint and extend the PIP and DIP joints by acting through the extensor hood
adductor pollicis
O: deep in the hand from 2nd & 3rd metacarpal bones and adjacent carpal bone
I: medial side of the base of the proximal phalanx of the thumb
N: deep branch of the ulnar nerve.
palmar interossei muscles
- found between the metacarpal bones
O: on the metacarpals
I: into the proximal phalanx and extensor hood.
Fxn: adduct the 2nd, 4th and 5th fingers towards the midline (palmar interossei adduct – PADs)
N:ulnar nerve.