Exam 2 Flashcards
what comprises the carpus, or wrist
- a core structure of 8 bones
- more than 20 radiocarpal, intercarpal, and carpometacarpal joints
- 26 named intercarpal ligaments
- the six or more parts of the triangular fibrocartilage complex (TFCC)
the hand accounts for about ___ % of upper limb funciton
90%
the thumb is involved in _____ of hand function
40-50%
the index finger (2nd digit) is involved in about ____ of hand function
20 %
this finger accounts for about 20% of all hand function, is the strongest finger, and is important for both precicsion and power fucntions
the middle finger (3rd digit) aka chiropractic index finger
distal radio-ulnar joint is what kind of joint
double pivot joint
distal radio-ulnar joint unites the
distal radius and the ulna and an articular disc (TFCC)
what does the rounded head of the ulnar head contact
it contacts both the ulnar notch of the radius laterally, and the TFCC distally
since the ulnar styloid process is approximately one-half inch shorter than the radial styloid process what does this result in
more ulnar deviation than radial deviation (ROM 30 degrees vs 20 degress)
fracture of the radius within 20-35 mm of the wrist joint with posterior angulation of the distal fragment
colle’s fracture
colle’s fracture is also known as a
dinner fork fracture
Mr. Smiths at the front door and cole is at at the back door
.
fracture of the radius within 20-35mm of the wrist joint with anterior angulation of the distal fragment
smiths fracture
smiths fracture is aka
garden spade deformity
the fibrocartilage disc in between the medial proximal row and the distal ulna within the medial aspect of the wrist
Triangular fibrocartilage complex (TFCC)
what is the primary function of the TFCC
to imporve joint congruency and to cushion against compressive forces
Scaphoid, lunate, and radius
3 bones involved in a direct articulation of the wrist
bones involved in indirect articulation of the wrist
ulna, triquentrium, pisiform
the TFCC transmits about _____ of the axial load from the hand to the forearm
20%
TFCC is made of
fibrocartilage (so are IVD’s * you should know this you future doc)
what is the wrist comprised of
distal radius and ulna, 8 carpal bones, 5 metacarpal bones
the carpal bones lie in
two transverse rows
what does the proximal row contain
(lateral to medial) scaphoid (navicular) lunate triquetrum pisiform
what does the distal row contain
trapezium
trapezoid
capitate
hamate
what is the most commonly fracture wrist bone
navicular
what is the largest bone of the proximal row
navicular (scaphoid)
ulnar deviation helps to slide which bone
navicular bone slides out from under the radial styloid process for palpation
what is the largest most prominent of the MCP bases
capitate
which is the largest of all carpal bones
capitate
what is the 2nd most often fractured and the most commonly subluxated
lunate
what bones are covered up by the extensor carpi radials brevis tendon which inserts into the base of the 3rd metacarpal
lunate
capitate
base of the 3rd metacarpal
which bones is the easiest to fall and become subluxed
lunate
(this forms the arch on the dorsum of the hand and a lot of our actions flatten out this curve and cause it to fall anterior)
the mid carpal joint lies between the
two rows of carpals
a _____ articulation because each row has both a concave and convex segment
compound
the proximal row of the carpals is ____ laterally and ____ medially
convex
concave
which bones present with a concave surface to the distal row of carpals
scaphoid lunate trapezium trapezoid triquetrum
which bones present with a convex surface to a reciprocally arranged distal row
scaphoid
capitate
hamate
articulation between he distal borders of the distal carpal row bones and the bases of the metacarpals
carpometacarpal joints
____ of the CMC joints is provided by the palmar and dorsal carpometacarpal and inter metacarpal ligaments
stability
what do the 2nd-5th metacarpals articulate with
the respective proximal phalanges in biaxial joints
the MCP joints allow ____ -____ and _____-_____ deviation associated with a slight degree of axial rotation
flexion-extension
medial-lateral
what shape is the first carpometacarpal joint
functionally the seller (saddle-shaped) carpometacarpal (CMC)
which joint is the most important of the thumb
first carpometacarpal joint
what articulation does the first carpometacarpal joint consists of
the articulation between the base of the first metacarpal and the distal aspect of the trapezium
what motions occur in the first carpometacarpal joint
flexion/extension
adduction/adduction
and opposition (which includes varying amounts of flexion, internal rotation, and palmar adduction)
how are the MCP’s and the IP’s normally held in during rest
a position of slight flexion
consider inspecting for damage
fracture though the base of the first metacarpal neck with dorsal and radial displacement of the shaft
bennett’s fracutre
posterior lateral
(doral medial)?
what type of joint is the metacarpophalaneal joint of the thumb
a hinge joint
what does the metacarpophalangeal joint of the thumb consists of
a convex surface on the head of the metacarpal, and a concave surface not he base of the phalanx
how many phalanges
14
what does a phalange consist of
base
shaft
head
what mark the concave proximal bases of the phalanges
two shallow depressions, which correspond to the pulley-shaped heads of the adjacent phalanges
what produce the pulley-shaped configuration of the phalangeal heads
two distinct convex condyles
fracture of the fourth or fifth metacarpal neck with ANTERIOR displacement of the head
Bar Room Fracture
fracture of the second or third metacarpal neck with ANTERIOR displacement of the head
Boxer’s fracture
what type of joints are interphalangeal joints
hinge joints that allow motion in only one plane
what contributes greatly to finger joint stability
the congruency of the IP joint surfaces
this joint is a hinged joint capable of flexion and extension
Proximal IP (PIP) joint
this joint has similar structures but less stability and allows some hyperextension
distal IP (DIP)
explain Heberden’s Nodes
1) found on one or more fingers, except the thumb
2) distal joints are enlarged by hard nodules, 2 to 3 mm in diameter, one on either side of the dorsal midline
3) nodules are painless; motion is unlimited
4) process is a localized OA
5) involvement of several joints is more common in women in home they appear at the menopausal age
6) condition in women is usually hereditary
7) single joint is more commonly involved in men
8) condition in men is usually the result of trauma
abnormal fusiform enlargement at the PIP joint which can indicate SYNOVITIS secondary to RA
Bouchard’s Nodes
MOI=RA
PIP joint deforms into hyperextension and the DIP joint is flexed
Swan Neck Deformity
the central slip of the extensor digitorum communist tendon is avulsed from the insertion in to the middle base of the middle phalanx, the PIP is flexed and the DIP is extended
MOI=trauma
Boutonniere Deformity
looks like a button over the PIP joint
what do the major ligaments of the wrist include
palmar instrinsic ligaments
volar extrinsic
dorsal extrinsic
intrinsic ligaments
the extrinsic palmar ligaments provide the majority of the
wrist stability
the intrinsic ligaments serve at _____ _____, binding the proximal row into a unit of rotational stability
rotational restraints
medial and lateral collateral ligaments of the fingers are named
Graysons (medial) and Cleland’s (lateral)
formed by the large articular concave surface of the distal end of the radius, the scaphoid and lunate of the proximal carpal row, and the TFCC
radiocarpal joint
a dense CONNECTIVE tissue “bracelete” that encases the forearm and maintains the relationships of the tendons that cross the wrist
antebrachial fasica
serves to prevent the tendons from “bow stringing” when the tendons turn a corner at the wrist
extensor retinaculum (this sister cries a lot)
what are the tunnel-like structures formed by the retinaculum and the underlying bones called
fibro-osseous compartments
what are the extensor retinaculum compartments, from lateral to medial,
- abbudctor pollicis longus and extensor pollicis brevis
- extensor pollicis longus
- extensor digitorum and indicis
- extensor digiti minimi
- extensor carpi ulnaris
this transforms the carpal arch into a tunnel, through which pass the median nerve and some of the tendons of the hand
flexor retinaculum
proximally, the retinaculum attaches to the
tubercle of the scaphoid and the pisiform
distally the retinaculum attaches to the
hook of hamate, and the tubercle of the trapezium
what is the condition known as when the median nerve is compressed in this relatively unyielding space
carpal tunnel syndrome
phalanx sign
avulsion of the flexor digitorum profundus tendon
jersey finger
what is the MOI for the jersey finger
the finger gets caught int an object and actively flexed DIP joint is suddenly and forcible extended resulting in a rupture
serves as a conduit for the median nerve and nine flexor tendons
carpal tunnel
what make the floor of the canal
the palmar radoiocarpal ligament + palmer ligament complex
what is the root of the tunnel
the flexor retinaculum (transverse carpal ligament)
within the tunnel the ulnar and radial borders are
trapezium and hook of hamate respectively