What are the MAJOR muscle groups of the forelimb?
Triceps brachii - long head, lateral head, median head, accessory heads in the dog. NB other species only have three heads.
Long head originates at infraglenoid tubercle of scapula; lateral & medial originate from shaft of humerus; all insert at olecranon of ulna; innervated by radial n.
Biceps brachii - originating at supraglenoid tubercle of scapula, inserting at radial tuberosity; innervated by musculocutaneous n.
Which nerve innervates the triceps brachii?
Which nerve innervates the biceps brachii?
What are the extrinsic muscles of the forelimb?
Where is the long head of the triceps brachii? Medial? Lateral? Cranial? Caudal?
The long head of the triceps brachii is caudal & medial.
Which nerves exit the brachial plexus & are visible on the MEDIAL aspect of the dissected brachium?
Musculocutaneous nerve - remember this innervates MEDIAL muscles, which tend to be flexors of the forelimb. It provides motor to biceps brachii and brachialis mm. Sensory to dorsomedial aspect of antebrachium
Median nerve - motor to flexors of the carpus and digits. Sensory to the palmar antebrachium and manus. Remember, medial muscles are FLEXORS.
Ulnar - motor to flexors of carpus and digits. Sensory to the palmar antebrachium and manus.
What muscles are innervated by the musculocutaneous nerve?
The musculocutaneous nerve runs medially down the forelilmb from the brachial plexus.
It innervates the biceps brachii & brachialis muscle.
The biceps brachii and brachialis muscles are flexors of the elbow.
The median nerve comes off the musculoskeletal. What does the median nerve innervate?
Like the musculoskeletal, the median nerve, as per its name, runs medially along the forearm, and thus innervates medially placed muscles that are FLEXORS of the carpus & digits.
What does the ulnar nerve innervate?
The ulnar nerve runs medially out of the brachial plexus along with the musculoskeletal & median nerves. At the elbow, it goes to the caudal aspect of the forearm.
It provides motor to flexors of carpus and digits. Sensory to the palmar antebrachium and manus.
The elbow is composed of 3 joints:
proximal radio-ulnar joint.
The anconeal process of the ulna fits into the
olecranon fossa of the humerus.
The elbow is a very stable joint allowing movement in the sagittal plane only, owing largely to the ligaments that hold it together. What are the ligaments of the elbow of the forelimb?
Lateral and medial collateral ligaments - between the humerus and radius
Olecranon ligament - between the olecranon fossa of the humerus and olecranon
Annular radial ligament - arranged as a semi-circle around the cranial edge of the head of the radius
Interosseus antebrachial ligament (or radio-ulnar ligament) - lies in the proximal space between the radius and ulna. It is ossified in the horse and ruminant.
Which nerve innervates the infraspinatus & supraspinatus muscles?
What are the major muscles GROUPS of the hindlimb?
Medial Muscles of the Thigh
Inner Pelvic Muscles
Muscles of the Stifle