Bones of the Proximal Forelimb & Shoulder Joint Flashcards
what is the orientation of the scapula in man and primates
horizontal orientation
what is the orientation of the scapula in domestic animals
vertical orientation –> shoulder joint relatively lower in limb, increases limb length
do domestical animals have a clavicle
absent, muscular attachment between forelimb & trunk
allows scapular glide & rotation about pivota point
produces increased stride length
restricted lateral movement (abduction/adduction)
what type of bone is the scapula
flat bone
what surfaces of the scapula are palpable
- dorsal border - palpable
- cranial border - palpable
- caudal border - not palpable (beneath muscle)
- scapular spine - palpable (supraspinous fossa, infraspinous fossa)
- acromion process - palpable (locate shoulder joint)
what is present on the ventral surface of the scapule
- glenoid cavity
- supraglenoid tubercle
what is the glenoid cavity
concave
smooth subchondral/articular surface for shoulder joint
what is the supraglenoid tubercle
attachment of biceps brachii muscle
what are the structures of the scapula
what are the medial/costal surface
flat & featureless –> scapular glide
rough bone - muscle attachment
how many centres of ossification does the scapula develop from
2 centres
body
supraglenoid tubercle
what are the features of cat scapula
more rounded cranial angle than dog
suprahamate process –> proximal to acromion process
what are the features of the scapula in larger species
tuber on spine
cartilage extension to dorsal border
what region is the humerus located in
brachium
what type of bone is the humerus
long bone
what is the shape of the humerus
S-shaped
what is on the proximal end of the humerus
- head
- greater tubercle
- lesser tubercle
- intertubercular groove
what is the shape of the humerus
convex
smooth articular surface for shoulder joint
is the greater tubercle palpable and what is this landmark used for
palpable (lateral)
location of shoulder joint
what passes through the intertubercular groove
biceps tendon
where is the lesser tubercle
medial
what are the structures of the humerus head
what is the shaft of the humerus
body
–what are the structures of the distal end
- condyle
- medial epicondyle - palpable
- lateral epicondyle - palpable
- trochlea (central depression, smooth articular surface for elbow joint)
- ulnar/olecranon fossa
- radial fossa
- supratrochlear foramen
what are these structures
medial and lateral epicondyles
* trochlea
where is the ulnar/olecranon fossa
caudal aspect
where is the radial fossa
cranial aspect
what are the features of the supratrochlear foramen
nothing passes through
may not be present in short legged dogs
absent in larger species (horse)
what structures do cats not have
no supratrochlear foramen
supracondyloid foramen –> blood vessels and nerves pass through
how many centres of ossification does the humerus develop from
5 centres
- proximal epiphyses
- body
- condyle –> medial epicondyle, medial half, lateral half