Forelimb Flashcards
The shoulder joint capsule envelops which tendon?
Tendon of origin of biceps
The shoulder joint capsule is reinforced by what?
2 thickenings- the medial and lateral glenohumeral ligaments
Subscapularis is innervated by which nerve?
Subscapular nerve
Supraspinatus and infraspinatus are innervated by which nerve?
Suprascapular nerve
Why is the suprascapular nerve liable to damage?
It passes close to the bone at the scapular notch
What clinical signs might an owner be aware of to indicate suprascapular nerve damage?
Prominent scapular spine (due to wasting away of supra- and infraspinatus)
Lameness
Which muscle runs in the musculospiral groove?
Brachialis
Which nerve and artery run in the musculospiral groove?
Radial nerve
Brachial artery
Which words are used to describe the joint connecting the forelimb to the trunk?
Omothoracic junction
Is a synsarcosis
What does the radial nerve do?
Extension of elbow
Flexion of shoulder (long head of triceps)
Extension of carpus and digits
What clinical signs would you see in proximal and distal radial nerve damage?
Proximal: Can’t extend elbow or weight-bear
Distal: Can’t extend carpus (if triceps are intact, can still extend elbow). Dog would drag paw along floor
Whart do the collateral ligaments connect in the elbow?
Humerus to the ulna and radius
Where does the annular ligament run in the elbow joint?
Runs from medial to lateral coronoid processes of the ulna, and encircles the radius, allowing it to rotate during pronation and supination
How would you access the medial elbow joint for surgery?
Between the superficial digital flexor muscle, and flexor carpi radialis
Where does the greatest movement occur within the carpal joint?
At the antebrachiocarpal joint and the middle carpal joints
Where are the interosseus muscles located in the dog?
What is its function?
(Analogous to the suspensory ligament in the horse)
4 in the dog. Each arises from the caudal, proximal end of the metacarpal bones, and divides in 2 as they run distally, to insert on a proximal sesamoid
Supports the caudal aspect of the metacarpophalangeal joint
The brachial plexus supplies which muscles?
All intrinsic forelimb muscles
Selected extrinsic muscles: pectorals, latissimus dorsi, serratus ventralis
Which nerves come off the brachial plexus?
Brachiocephalic nerve Suprascapular nerve Subscapular nerve Musculocutaneous nerve Superficial (or cranial) pectoral nerve Axillary nerve Radial nerve Thoracodorsal Median nerve Ulnaer nerve Deep (or caudal) pectoral nerve
Which 2 vessels supply most of the blood to the foot?
Caudal interosseus artery (branch of common interosseus which is final branch of brachial artery), along with the main continuation of the median artery
Where does the cephalic vein run?
Up the cranial aspect of the limb. Deep to brachiocephalicus. Joind the jugular vein
What is the origin, insertion, action and innervation of extensor carpi radialis?
O=lateral supracondylar crest of humerus
I=metacarpals 2 and 3 (dorsal surface)
A=extends the carpus
In=Radial nerve
What is the origin, insertion, action and innervation of common digital extensor?
O=lateral epicondyle of humerus
I=distal phalanx of digits 2-5
A=extends the carpus and digits 2-5
In=radial nerve
What is the origin, insertion, action and innervation of the lateral difital extensor?
O=lateral epicondyle of humerus
I=all phalanges of digits 3-5 (mainly distal phalanx)
A=extends the carpus and digits 3-5
In=radial nerve
What is the origin, insertion, action and innervation of ulnaris lateralis?
O=lateral epicondyle of humerus
I=lateral aspect of metacarpal 5, and accessory carpal bone
A=abduct the manus, flex the carpal joint, support carpus when extended
In=radial nerve
Where is the abductor pollicis longus located?
Lies in the groove between radius and ulna
What is the origin, insertion, action and innervation of abductor pollicis (digiti I) longus ?
O=lateral border and cranial surface of ulna, and interosseous membrane
I=proximal end of metacarpal 1
A=abduct the first digit, extend the carpal joints
In=radial nerve
What is the origin, insertion, action and innervation of flexor carpi ulnaris?
O=ulnar head: olecranon of ulna (smaller)
humeral head: medial epicondyle of humerus (larger)
I=accessory carpal bone
A=flex the carpus
In=ulnar nerve
What is the origin, insertion, action and innervation of flexor carpi radialis?
O=medial epicondyle of humerus, medial border of radius
I=palmar aspect of metacarpals 2 and 3
A=flex the carpus
In=median nerve
What is the origin, insertion, action and innervation of the superficial digital flexor muscle?
O=medial epicondyle of humerus
I=palmar aspect of middle phalanx of digits 2-5
A=flex the carpal, metacarpophalangeal and proximal interphalangeal joints of digits 2-5
In=median nerve
What is the origin, insertion, action and innervation of the deep digital flexor?
O=humeral head (biggest): medial epicondyle of humerus radial head (smallest): medial border of radius ulnar head: caudal border of ulna I=palmar surface of distal phalanx, digits 1-5 A=flex the carpal, metacarpophalangeal, proximal and distal interphalangeal joints of the digits In=median and ulnar nerves
Where does pronator quadratus lie?
Fills the interosseous space between the ulna and radius
What passes through the carpal canal in a dog and cat?
What is the carpal canal formed by?
Median and ulnar nerves
DDFT
Blood vessels and nerves
Laterally: accessory carpal bone
Dorsally: fibrocartilagenous reinforcement of carpal joint capsule
Palmar: flexor retinaculum
What passes through the carpal canal in the horse?
What about ruminants and pigs?
Horse: Both DDFT and SDFT
Ruminants and pigs: DDFT and half of SDFT (splits)
What is the main route of blood supply to the forelimb?
Subclavian artery becomes axillary artery, becomes brachial artery at the teres major tuberosity, gives off common interosseous (which branches into cranial and caudal interosseous), brachial artery becomes median artery, gives off ulnar and radial branches
