Damage To Thoracic Limb Nerves Flashcards
What happens if the suprascapular nerve is damaged?
Atrophy of the infraspinatus and supraspinatus and subsequent prominent scapular spine.
Decreased ability to laterally stabilize the shoulder.
Called “Sweeney” in the horse –> horse has no acromion to protect this nerve
What happens is the subscapular nerve is damaged?
Decreased ability to medially stabilize the shoulder.
No significant clinical signs.
What happens if the musculocutaneous nerve is damaged?
Flexor reflex at elbow is weak.
Loss of cutaneous sensation on medial aspect of antebrachium.
What happens if the axillary nerve is damaged?
Weakened shoulder flexor reflex (deltoideus m.)
Decreased ability to stabilize the shoulder
Loss of cutaneous sensation on the lateral aspect of the brachium nad caudal scapular region .
What happens if the lateral thoracic nerve is damaged?
Loss of skin twitching reflex may or may not be indicative of damage to this nerve.
Panniculus reflex makes use of this nerve to test ascending sensory spinal pathways.
What happens if the radial nerve is damaged proximal to the branches supplying the triceps brachii?
Produces complete loss of extension of all joints distal to the shoulder.
Inability to bear weight on this limb.
Loss of cutaneous sensation on dorsal and lateral aspects of antebrachium and dorsal paw.
What happens if the radial nerve is damaged distal to the nerves supplying the triceps brachii?
Permits extensions of the elbow, but you will see knuckling over onto the dorsal aspect of the forepaw.
Loss of cutaneous sensation on dorsal and lateral aspects of antebrachium and dorsal paw (distal to where nerve is damaged)
What happens is the median nerve is damaged?
Loss of active flexion of the carpus.
Slight weakness of carpus and fetlock resulting in a slight sinking of the carpus and fetlock.
What happens if the ulnar nerve is damaged?
Loss of cutaneous sensation on lateral aspect of the paw.
What is brachial plexus avulsion?
Where the roots of spinal nerve that contribute to the brachial plexus are torn (either partial or complete).
What happens in brachial plexus avulsion of the radial nerve roots (C7-T1)?
Inability to support weight
What happens in brachial plexus avulsion of the suprascapular and subscapular nerve roots (C6, C7) and supply to brachiocephalicus m. (C6)?
Animal cannot stabilize the shoulder or advance the limb
What happens in brachial plexus avulsion of the musculocutaneous nerve roots (C6-C8)?
Animal cannot lift limb off the flow; inability to flex elbow.
