Exam 2 Thoracic Limb Flashcards
point of shoulder in horse
cranial part of the greater tubercle of the humerus
which animal has cranial and caudal parts
idk
id parts of bones
k
what passes through the medial gorrove in the radius
extensor carpi obliquus tendon
what passes through the middle groove in the radius
extensor carpi radialis tendon
what passes through the lateral groove in the radius
common digital extensor tendon
radius and ulna in the horse
fused distally
radius and ulna in the ruminants
shaft of ulna comes all the way down
dorsoscapular ligament is present in the
horse
what is the dorsoscapular ligament
part of the thoracolumbar fascia in the area of the withers
dorsoscapular ligament has several
layers or lamella
dorsoscaplar ligament attaches to
thoracic spins (and supraspinous ligament) at the withers (T3 to T5)
What is the dorsal part of the dorsoscapular ligament composed of
dense, colagenous connective tissue
ventral part of dorsoscapular ligament
thinner and has numerous elastic fibers as well as CCT
Ventral part of dorsoscapular ligament has numerous
lamellae that intersect scapular part of serratus ventralis m.; lamellae attach to deep surface of the scapula
what is the function of the dosroscapular ligament
helps absorb concussive force of the foot as it strikes the ground to reduce upward (dorsal) movement of the scapula
origin of dorsoscapular ligament is next to
supraspinous bursa
infection of supraspnous bursa can lead to
draining tracts that follow lamellae of dorsoscapular ligament; over days to weeks, swelling can occur; can be in multiple locations-swellings rupture and release mucopurulent discharge
how to cure this
difficult to cure; medical management alone is rarely effective- need surgical debridement as well as medical treatment
in the horse, superficial thoracic vein (spur vein) drains into
thoracodorsal vein which drains into the axillary vein
OR the spur vein drains directly into the axillary vein
subclavious attachments in the horse
originates at cranial sternum (1st to 4th costal cartilages) and inserts at aponeurosis over dorsal part of supraspinatus m. and shoulder fascia
what is the innervation of the subclavious
pectoral nn.
what is the action of the subclavious
adduct and retract the thoracic limb; when limb is advanced and fixed, to draw the trunk cranially
supraspinatus attaches to
greater and lesser tubercles of humerus
infraspinatus superficial tendon attaches to
on lateral surface of the greater tubercle of umerus distal to the supraspinatus attachment
what bursa is between the superficial tendon of infraspinatous and the caudal part of the greater tubercle of the humerus
infraspinatus bursa
where does the deep tendon of the infraspinatous
on the caudal part of the greater tubercle
what muscle stabilizes the shoulder joint
supraspinatus m.
what muscle is a lateral stabilizer of the shoulder joint
infraspinatous
what is the medial stabilizer of the shoulder joint
subscapularis m.
triceps brachii m. origin of long head
caudal border of scapula
triceps brachii m. origin of lateral head
deltoid tuberosity, proximal lateral humerus, fascia along lateral brachium
triceps brachii m. origin of medial head
middle third of medial humerus, caudal and distal to teres major tuberosity
insertion of the muscles of the triceps brachii
olecranon
innervation of the tricpes brachii
radial nerve
action of the triceps brachii mm.
extned the elbow jt, long head also flexes the shoulder joint
subtendinous bursa location
between long head of the triceps brachii and the olecranon
subcutaneous bursa location
between the tricpes brachii tendon and the skin “capped elbow”
biceps brachii m. origin
supraglenoid tubercle
biceps brachii m. insertion
radial tuberosity of th eradus, medial collateral ligament of the elbow joint, antebrachial fascia, tendon of extensor carpi radialis via lacertus fibrosus
lacertus fibrosus
tendinous insertion of biceps brachii on the extensor carpi radialis; part of the stay apparatus; poorly developed in ruminant
intertubercular bicipital bursa in horse and ox
separate from the shoulder joint
intertubercular bursa of sheep and goat
a pouch of shoulder joint capsule that extends into the intertubercular groove
review osteology of distal limb
x
what bone is often missing in the horse
first carpal bone
if the first carpal bone is present in the horse, where is it located
embedded in the medial collateral ligament
in the ruminant, what does the accessory carpal bone articulate with
ulnar carpal bone in ruminants only
cannon bone of horse
metacarpal 3
what are splint bones in the horse
metacarpals II and IV
distal ends of the splint bones are called
buttons
long pastern bone
proximal phalanx (PI)
short pastern bone
middle phalanx (PII)
coffin bone
distal phalanx (PIII)
Proximal sesamoid bones in horse
meidal and lateral
distal sesamoid bone o fthe horse is also called
navicular bone
in ruminant, what metacarpals are present
fused metacarpals III and IV
What metacrapal is rudimenatry in ruminant
metacarpal V
vestiges
“dewclaws” digits 2 and 5
what are the weight bearing digits of the ruminant
digits 3 and 4
what proximal sesamoid bones are present in the ruminant
axial and abaxial for each digit
distal sesamoid bone
1 per digit
chestnuts
vestigial carpal/tarsal pads in the horse
where are chestnuts located
medial aspect of the thoracic and pelvic limbs
in the thoracic limb, chestnuts are _____ to carpus
proximal
in the pelvic limb, chestnuts are located _____ to the hock
distal
ergots
rudimentary metacarpal/metatarsal pads on each limb palmar to the fetlock
ligament of ergot
deep to skin, cross over digital vessels and nerve and blends into digital vessels
shoulder joint capsule
extension surrounding tendon of biceps brachii m. in small ruminants but no tin horse and ox
elbow joint capsule
has cranial and caudal pouches
medial collateral ligament of elbow joint
extends from medial epicondyle of the humerus to the medial border of the radius
lateral collateral ligament of the elbow joint
extends from the lateral epicondyle of the humerus to the lateral border of the radius
joint compartments of the carpus in large animals includes
raadiocarpal (antebrachiocarpal) joint
middle carpal joint
carpometacarpal joint
flexion of antebrachiocarpal joint
90-100 degrees
middle carpal joint flexion
45 degrees
carpometacarpal joint
little to no movement
what carpal joints communicate
middle carpal joint and carpometacarpal joint
synovial sheaths of extensor tendons
carpal extensors and digital extensors
carpal sheath
common tendon sheath for superficial and deep digital flexor tendons from proximal tot he carpus to the proximal 1/2 of the metacarpus
lateral digital extensor of eqine attaches on
proximal end of proximal phalanx (PI)
Lateral didgital extensor of ruminants attaches to
proximal end of middle and distal phalanges (PII and PIII OF DIGIT 4)
Common digital extensor of equine attaches to
extensor process of distal phalanx (PIII) with additional attachments at proximal ends of proximal nd middle phalanges
common digital extensor m. of ruminants
medial had attaches on proximal end of middle and distal phalanges
lateral head divides into 2 tendons to attach to extensor process of distal phalanx of digits 3 and 4
where carpal canal located
medial to accessory carpal bone and deep to flexor retinaculum
what is the dorsal boundary of the carpal canal
palmar carpal ligament
what is the lateral boundary of the carpal canal
accessory carpal bone
what is the palmaromedial boundary of the carapal canal
flexor retinaculum
what is located in the carpal canal
deep digital flexor tendon
superficial digital flexor tendon
median artery and medial palmar nerve
flexor carpi radialis m.
interosseus muscle of horse origin
3rd interosseus m.; originates from distal row of carpal bones and proximal metacarpal III
interosseus muscle of horse insertion
abaxial surfaces of proximal sesamoid bones; and to common digital extensor tendon by way of extensor branches
action of interosseus muscle of horse
works with other ligaments of the proximal sesamoids to support the fetlock by preventing overextension
interosseus m. of ruminants
composed of both msucle and tendon
in young animals it may be almost entirely muscle
predominately tendinous in older animals
interosseus m. of ruminants origin
palmar carpal ligament and proximal palmar surface of metacarpal III/IV
interosseus m. of ruminatns insertion
proximal sesamoids of both digits; branches to extensor tendons; accessory ligament attaches to suprficial digital flexor m.
what is the action of the interosseus m.
support fetlock joints; helps form flexor manica for deep digital flexor m.
what is the function of the suspensory apparatus of the fetlock joint
suspends the fetlcok joint to prevent hyperextension when bearing weight; energy is stored in the apparats due to stretching of the ligaments on the hoof impact with ground; this energy is released at the end of the stride allowing forward movement. Acts like a spring.
what does the supsenosry apparatus consist of
interosseous m., proximal sesamoid bones, and distal sesamoidean ligaments
proximal sesamoid bones are anchored distally by the _____
distal sesamoidean ligaments (XYZ ligaments)
straight sesamoidean ligament
Z ligament
most superficial- attaches to proximal end of middle phalanx
oblique sesamoidean ligament
Y ligament
deep to straight sesamoidean ligament to roughened area on palmar aspect of proximal phalanx
cruciate sesamoidean ligaments
X ligament
deepest; from base of each sesamoid bone to the opposite eminence on proximal end of proximal phalanx
what is the proximal check ligament
accessory ligament of superficial digital felxor tendon
course of proximal check ligament
runs between distal, caudal radius and superficial digital flexor tendon; proximal to carpus
distal check ligament
accessory ligament of deep digital flexor tendon
course of check ligament
runs between palmar carpal ligament and deep digital flexor tedon; located distal to the carpus
what is the function of the check ligaments
check or limit the action of the superficial and deep digital flexor muscles; part of the stay apparatus of the toracic limb
know synovial parts of the distal limb
x
where is the navicular bursa located
between deep digital flexor tendon and the distal sesamoid bone; close proximity to coffin bone
do navicular bursa and coffin joint communicate
not usually
deep digital flexor m. tendon _____ along its attachment ot the flexor surface of the distal phalanx
fans out
digital tendon sheath in the horse is caudal to
distal end of interossues m.
digital tendon sheath is clost to
proximal palmar pouch (recess) of fetlock joint; does not communicate with fetlock joint
digital tendon sheath is shared by
deep digital flexor m. tendon and superficial digital flexor m. tendon
where does the digital tendon sheath start
a few centimeters proximal to the fetlock joint
where does the digital tendon sheath end
at middle of PII
digital tendon sheath is a common site for
inflammation
deep digital flexor m. tendon crosses the fetlock joint in the ____ formed by the superficial digital flexor m. tendon
sleeve
digital flexor tendons are held in place by waht 3 ligaments
palmar annular ligament
proximal digital annular ligament
distal digital annular ligament
in the ruminant, the fetlock, pastern and coffin joints are all
duplicated joints
all joints in the ruminant distal limb have
dorsal and palmar pouches
large joint capsules at
fetlock
_____ pouches of fetlock joints are larger than _____ pouches
palmar; dorsal
________ communicate between the 2 fetlock joints
left and right feltock joint capsules
the pastern and coffin joints are all
separate
equine foot
hoof and everything inside of the hoof
hoof
outer part of foot (epidermis and dermis)
hoof capsule
epidermal part of hoof
hoof divides externally into
walll
frog
sole
coronet
junction of skin andhoof
wall highest at the _____
toe; height decreases over the quarters
angle of wall at toe
about 50 degrees in the thoracic limb (range 48 to 60)
periople
widens at palmar aspect of hoof wall; covers bulbs of the heels
peirople is
stratum externum composed of tubular and intertubular horn
stratum externum is a ____ layer
thin
majority of hoof wall is
stratum medium; composed of tubular and intertubular horn
growth of wall
0.6 to 0.8 cm per month
takes ________ for newly formed stratum corneum to move width of the hoof wall (proximal to distal)
8 months
depression in center of frog
central groove
groove coresponds to
internal spine (frog stay)
frog separated from bars by
paracuneal grooves (collateral grooves)
grooves are common sites of
thrush
base of frog blends into
bulbs of the heels
frog (and sole) horn consists of
tubular and interubular horn
what is the function of the dermis
supports the 5 different epidermal regions
what attaches dermis to deeper structures
subcutis (hypodermis)
what produces the hoof capsule
stratum basale of epidermis
peiroplic dermis supports
stratum externum
coronary dermis supports
stratum medium
laminar dermis supports
stratum internum
sole supports
sole
frog of dermis supports
frog
due to the presence of dermal papillae, tubular and intertubular horn is produced in
perioplic, coronary, frog, and sole regions of epidermal hoof
stratum internum has
primary and secondary laminiae
primary dermal laminae interdigitate with
primary epidermal laminae
basement membrane located between
stratum basale and dermis
what is the white zone
junction between sole and wall
white zone ncludes
innermost part of stratum medium of the wall
distal ends of primary laminae of stratum internum
pigmented horn produced by stratum basale over terminal papillae located at distal end of laminar dermis
subcutis is thickened in 2 places
coronary cushion and digital cushion
coronary cushion
deep to coronary dermis
highly elastic
coronary dermis and cushion fill the coronary groove of hoof
contains coronary venous plexus
digital cushion
subcutis deep to palmar part of hoof capsule
digital cushion is composed of
collagenous connective, elastic fibers, and adipose tissue
bulbs of cushion undely
bulbs of heel
digital cushion contains
modified sweat glands and the fat rich secretions help keep frog pliable
the duct pass through the
dermis of the frog
digital cushion assits with
shock absorption and venous return
blood supply of the dermis
branches of the medial and lateral digital arteries supply all regions of the dermis and the coronary and digital cushions; veins do not parallel the arteries in the foot
veins form
interconnected networks especially in the coronary band (coronary plexus), laminar dermis (dorsl plexus) and palamar aspect of the hoof (palmar plexus)
what pumps blood from plexuses into medial and lateral palmar digital veins, which have valves
pressure on foot
minimum radiographic views of the limbs & head
orthogonal veiws: dorsopalmar/craniocaudal; lateral
view rads
x
