Bones - SA Flashcards
What are the regions of the forelimb?
Omo - shoulder Brachium Antebrachium Carpus Manus Digits
The scapula glides over the thorax at what point? Where is this?
Pivotal point
Half way down the scapula
What muscles attach the forelimb to the body?
Serratus ventralis
Subscapularis
What is different about the scapula of a cat? (3)
Rounded cranial border
Suprahamate process
Cats have bony remnant of clavicle, dogs have cartilaginous
How many ossification centres does the scapula have?
2 - body and supraglenoid tubercle
Which part of the scapula is not palpable?
Caudal border - beneath muscle
What is the name of the synsarcosis (fleshy, muscular joint) between the forelimb and the thorax?
Omothoracic junction
What type of joint is the shoulder joint? What about it is different from the typical joint features?
Synovial
Poorly developed collateral ligaments
What is the bicipital bursa? What does it wrap around?
Extension of joint capsule into inter tubercular groove
Tendon of biceps brachii
What ligament holds the bicipital bursa in place?
Transverse ligament
Which muscle wraps around the musculospiral groove of the humerus?
Brachialis
What passes through the supratrochlear foramen in dogs? When might this foramen not be present?
Nothing
Short legged dogs
What passes through the supracondylar foramen in cats?
Brachial artery
Median nerve
What part of the humerus is vulnerable to fractures?
Supratrochlear foramen
How many ossification centres are in the humerus?Where are they?
5 - proximal epiphysis, body, 3 on condyles
What are the functions of the radius and ulna bones?
Radius - short and weight bearing
Ulna - long and for leverage
What keeps the radial notch of the ulna in contact with the radius?
Annular ligament
Is the ulna or radius most medial?
Proximal - ulna most medial
Distal - radius most medial
What ligament is found between the radius and ulna (interosseous space)?
Interosseus ligament
What is different about the ante brachium in cats?
Radius and ulna similar diameter
Square olecranon
Why do ulna fractures not always need repairing?
Non-weight bearing
How many ossification centres does the radius have? What are they?
3 - proximal epiphysis, body, distal epiphysis
How many ossification centres does the ulna have? What are they?
4 - anconeal, olecranon, body, distal epiphysis
What type of joint is the elbow?
Typical synovial (with collateral ligaments)
What 2 ligaments are present between the radius and ulna? Do these allow movement in cats and dogs?
Annular ligament
Interosseus ligament
Yes - more in cats
What type of bones are present in the forelimb (long etc)
Flat
Long
Short
Sesamoid
How many ossification centres do bones of the carpus have?
1
Except accessory and fused radial intermediate carpal have 2
What are the 3 joints present in the carpus?
Antebrachiocarpal joint
Middle carpal joint - between proximal and distal row
Carpo-metacarpal joint
Which joints in the carpus have most and least movement?
Antebrachiocarpal joint - most
Middle carpal joint - some
Carpo-metacarapl joint - least
What supports the palmar aspect of the carpal joint?
Fibrocartilaginous support
What is the retinaculum? What does it form?
Sleeve of deep fascia enclosing the carpus
Carpal canal
What runs through the carpal canal in small animals?
Deep digital flexor tendon (SDFT runs OUTSIDE of carpal canal)
Blood vessels and nerves
What type of walkers (e.g. plantigrade) are cats and dogs?
Digitigrade
What is the dew claw?
Vestigial first digit, non weight bearing
How many ossification centres do the metacarpals have?
2
How many ossification centres do the proximal and middle phalanx?
2
How many ossification centres does the distal phalanx have?
1
What joints are in the manus?
Metacarpo-phalangeal joint
Proximal interphalangeal joint
Dital interphalangeal joint
What type of joints are in the manus? What provides stability to them?
Synovial (typical)
Collateral ligaments, sagittal ridge/groove
How many sesamoids are in the manus per digit?
2 proximal
1 dorsal -
What is the function of the sesamoid bones?
Proximal - protect flexor tendon
Dorsal - protect extensor tendons
Are the sesamoid bones within or outside of the joint capsule?
Proximal are within joint capulse
Dorsal are outside of joint capsule
What is the horse equivalent to the interosseous muscle in dogs?
Suspensory ligament
How many interosseous muscles are there per manus? Where do they insert?
4 - split and insert onto each proximal sesamoids
How are the claws not visible in the cat?
Retracted due to strong dorsal elastic ligament and hyperextended DIP joint
Why are claws not visible in cat?
Rest in sheath so remain sharp for hunting
When are cats claws exposed?
If deep digital flexor flexes joint
If manual pressure applied to digital pad
Which bones do the DDF T and SDFT insert on?
DDFT - Proximal phalanx 1 (P1)
SDFT - P2
Why does the SDFT form a tunnel for the DDFT to pass through?
SDFT is superficial, but DDFT needs to bypass it to insert onto P1