The brachial plexus of ox derives from the ventral branches of the last three cervical and first two thoracic nerves. If you want to get the best guide to learn the anatomy of the brachial plexus of an ox, this article is for you. Here, I will show you the formation of brachial plexus, branches, and their innervation in an ox, sheep, and goat.
I will also show you the distribution of three significant nerves (radial, median, and ulnar) from the brachial plexus; these innervate the digits of an ox. You will get the brachial plexus of ox and goat labeled diagram that might help you identify all the nerves from the actual sample.
I will try to simplify the courses of radial, median and ulnar nerves with a labeled diagram. Don’t forget to grab the resources (radial nerve course) that I have attached to this article. Fine, let’s start to learn the brachial plexus anatomy from an ox or a goat.
Formation of brachial plexus of ox
First, I would like to inform you how the brachial plexus forms in animals (like – ox, goat, sheep, and dog). The brachial plexus of the ox is formed by the convergence of ventral branches of the last three cervical and two thoracic spinal nerves. But, in sheep and goats, the ventral branches of the last three cervical and only the first thoracic spinal nerves from the brachial plexus.
If you don’t know about the term plexus, then these few words are for you. The plexus is a branching network of vessels (blood or lymphatic) or nerves (axons outside the central nervous system). So, the term nerve plexus means – a plexus of intersecting nerves.
Major plexus of the animal body (nerve)
There are several nerve plexus in the animal body, like – spinal plexus and autonomic plexus. In the spinal plexus of an ox, you will find cervical plexus, brachial plexus, lumbar plexus, sacral plexus, and coccygeal plexus.
Again, in the autonomic plexus, you will find celiac plexus, Auerbach’s plexus, and Meissner’s plexus. I hope you could understand the term “plexus”. So, let’s get into the main part of the article.
Location of brachial plexus of ox
So, where the brachial plexus of the ox is located? The brachial plexus is located in between the thoracic wall and the medial of the shoulder. Could you find this location in ox?
If you open this area in ox, you will also find some essential muscles. I hope you have heard the name of the scalenus muscle of an ox or a goat. The brachial plexus remains superficial between the two branches of the scalenus muscle.
The major supply of brachial plexus
I will tell you the specific supply of every nerve from the brachial plexus of an ox or a got. Overall, the primary supply of a brachial plexus are as follow –
- Muscles and skin of the forelimb of an ox, sheep, and goat
- The particular parts of the thorax and neck of the ox.
List of significant branches of brachial plexus of ox
You will find more than eleven nerves in the brachial plexus of an ox. I will enlist all these nerves with their specific supply or innervation in an ox and goat. If you have a good piece of knowledge on the anatomy of forelimb bones and important muscles, it will be easy for you to memorize the name of all brachial plexus’s nerves.
- Suprascapular nerve of brachial plexus
- Subscapular nerve of ox
- Pectoral nerve (caudal and cranial pectoral in ox)
- Musculocutaneous nerve (have two branches – coracobrachialis and biceps brachii nerves)
- The axillary nerve of the brachial plexus
- The radial nerve of the ox (important nerve, and you might know the course of this nerve)
- Median nerve of the ox (another important nerve and don’t avoid learning the course of this nerve)
- The ulnar nerve of an ox (you might also learn the course of this nerve with their primary supply)
- The thoracodorsal nerve of ox
- Long thoracic nerve of brachial plexus and
- The lateral thoracic nerve of an ox.
I will discuss the detailed course and innervation of radial, median, and ulnar nerves from the brachial plexus. But, I would like to provide a little information about the other nerves of the brachial plexus of ox.
Suprascapular and subscapular nerve of ox
The suprascapular nerves derive from the sixth and seventh cervical components of the brachial plexus. It crosses the lateral surface of the brachial plexus and supplies to subscapularis, supraspinatus, and infraspinatus muscles.
Again, the subscapular nerve derives from the ventral branches of the sixth and seventh cervical nerves in ox. You will find two subscapular nerves in the brachial plexus of ox. These nerves innervate the subscapularis muscle of the ox.
The pectoral and axillary nerve of ox
The formation of a pectoral nerve may vary in ox. It may form essentially by the ventral branches of the brachial plexus’s seventh and eighth cervical components. Again, you may also find the ventral branch of the first thoracic spinal nerve in ox.
The most identifying feature of a pectoral nerve is the formation of a loop. These features might help you to identify the pectoral nerve from the brachial plexus.
As I informed you before, there are two parts of the pectoral nerve – cranial and caudal. The pectoral nerve forms a loop between the cranial pectoral nerve and the axillary nerve. This cranial pectoral supplies most of the pectoral muscle of an ox.
Again, the caudal pectoral have no association with the formation of any loop. It supplies the pectoralis ascending muscle of an ox.
The axillary nerve of an ox is formed by th e ventral branch of a brachial plexus’s seventh and eighth cervical spinal component. It passes between the subscapular artery and the subscapularis muscle (caudal to the shoulder joint). It innervates to the teres major, teres minor, deltoideus, and caudal part of the subscapularis muscles of an ox. The axillary nerve of an ox has a close association with the radial nerve.
The musculocutaneous nerve of ox
The musculocutaneous nerve is very easy to identify as it forms a distinct loop in the brachial plexus. This might also help you identify the other structure (median nerve) from the brachial plexus of ox. So, you might know how the musculocutaneous nerve forms the loop in the brachial plexus?
The musculocutaneous nerve crosses the lateral face of the axillary artery and joins the median nerve to form a loop ventral to the vessels. The name of this loop is ansa axillaries. I hope you could identify and make the difference between a nerve and an artery grossly.
So, first, you might identify the artery, then find the loop formed by the musculocutaneous and median nerve.
You will find two branches of a musculocutaneous nerve of ox. These branches will supply to coracobrachialis and biceps brachii muscles.
After coursing caudal to the biceps brachii muscle, the muscular musculocutaneous divides into one branch. It supplies to the brachialis and continues as the antebrachial nerve.
Thoracodorsal and long thoracic nerve of ox
The thoracodorsal nerve of ox derives from the ventral branches of the seventh and eighth cervical spinal nerves. It locates just caudal to the axillary nerve and supplies mainly to the latissimus dorsi muscle of ox.
The long thoracic nerve courses laterally between the scalene muscles in an inconsistent manner without entering the brachial plexus of ox. It supplies to the serratus ventralis thoracic muscle of an ox. In addition, the lateral thoracic nerves of ox supply to the skin and lateral thoracic wall.
Radial nerve from brachial plexus of ox
Do you think the course of a radial nerve from the brachial plexus of an ox is too much hard to memorize? If your answer is yes, you are wrong. I will show you the easy way to learn the courses of any nerve of the animal’s body. Here, I will present the course of a radial nerve of an ox most simply. You may grab the resource (course of radial nerve pdf) to learn the radial nerve quickly.
Okay, make sure you know at least the name of forelimb bones, major muscles, and joints from an ox. First, let’s make a list of what you should require to learn a radial nerve course.
Bones and joints of the forelimb of an ox
If you have a good piece of knowledge on the different segments of the forelimb with their bones involvements in an ox, you may skip this part. You will find four different segments in the forelimb of an ox.
- Thoracic girdle of ox – consists of the scapula bone
- The arm of an ox – consists of the humerus bone
- Forearm of an ox – consists of radius and ulna bones and
- The maneus of ox – consists of carpal, metacarpal, and phalanges
You will find the shoulder joint in between the scapula and humerus of the ox. Again, the elbow joint of ox locates in between the humerus and radius and ulna bones. You might also know the location of other joints (like carpal, metacarpal, fetlock, pastern, and coffin) from the forelimb of an ox. I have shown everything from the forelimb of an ox in the labeled diagram.
You might know the following essential muscles from ox forelimb to learn the course of radial nerve –
- The long and lateral head of triceps brachii muscles of ox
- Brachialis muscle of ox
- Extensor carpi radialis muscle of ox
- Extensor digitorus medialis muscle of ox
- Extensor digitorus communis muscle of ox
- Extensor digitorum lateralis muscle of ox
- Ulnaris lateralis muscle of ox and
- Flexor carpi lateralis muscle of ox
Make sure you could identify these muscles from the forelimb of an ox. Let’s start to learn the course of the radial nerve of an ox (from the thoracic girdle to digits).
“Before going to the course of radial nerve from the brachial plexus of ox, you might know in which aspect of digits they are supplying. That might help you to understand and learn the course of radial nerve perfectly. The radial nerve of ox supply the cranial and cranio-medial aspects of digits.”
So, you may prove that the radial nerve supplies the cranial and cranio-medial aspects of digits. Haha, I know this is not a math or any scientific method of studying the nerve course. But, this might be your method for better understanding. At the end of the course, I will show you how you could prove the radial nerve supply at cranial and cranio-medial aspects of digits.
The radial nerve in a thoracic girdle of an ox
The radial nerve of ox derives its fibers entirely from the ventral branches of the seventh and eighth cervical and first thoracic spinal nerve. It inclines ventrally and caudally at the thoracic girdle region of an ox.
The radial nerve of the ox brachial plexus relates to the subscapular and thoracodorsal arteries. In addition, this nerve also relates with the external thoracic vein medially.
The radial nerve in the arm region of an ox
You will find the radial nerve at the lateral aspect of the arm of an ox (at the musculospiral groove of the humerus). It runs in between the long and lateral head of the triceps brachii muscles of ox. Here, you will also find a collateral radial artery accompanying the radial nerve of an ox.
At the cranio-distal border of the lateral head of the triceps brachii muscle, the radial nerve divides into two branches – superficial and deep branch. The superficial branch of the radial nerve has a definite course and supply to the digits of the ox.
In addition, the deep branch of the ox radial nerve passes in between the brachialis and extensor carpi radialis muscles. It provides variable numbers of muscular branches that supply extensor carpi radialis, extensor digitorum medialis, extensor digitorum communis, extensor digitorum lateralis, and ulnaris lateralis.
The superficial branch of the ox radial nerve runs in between the brachialis and extensor carpi radialis muscles of the ox. Here, it gives some twigs that innervate the cranio-lateral aspect of the capsule of the elbow joint.
A radial nerve in forearm region of ox
You will find the radial nerve at the cranio-medial aspect of the forearm of an ox. It courses in between the extensor carpi radialis and flexor carpi radialis muscles of the ox. Here, the radial nerve remains more superficial and then enters deep into these two muscles.
The radial nerve in maneus region of ox
You will find the radial nerve at the dorso-medial aspect of the carpus of ox. In addition, at the metacarpus, the radial nerve will run along the dorsolateral aspect. Again, slightly proximal to the fetlock joint, it divides into dorsal common digital nerve II and III.
The dorsal common digital nerve II will supply digit II (as dorsal proper digital nerve II), and digit III as dorsal proper digital nerve III (abaxial).
Again, the dorsal common digital nerve III will supply to the digits III and IV. The dorsal common digital nerve will supply digit III on it’s axial surface as dorsal proper digital nerve III (axial). In addition, dorsal common digital nerve III will also supply the axial surface of digit IV as dorsal proper digital nerve IV (axial).
If you notice, the dorsal common digital nerve II supply the whole digit II and the medial aspect of digit III. So, you may say, this nerve supply to the cranio-medial aspect; ok?
Again, the dorsal common digital nerve III supplies the cranial (axial) surface of digits III and IV. That means it supplies the cranial aspect of the digits III and IV.
So, you have proved that the radial nerve of ox supplies to the cranio-medial and cranial aspect. I hope you will learn the course of median and ulnar nerves of an ox in the same way.
Median nerve from brachial plexus of ox
I will also show you the short course of the median nerve from the brachial plexus of ox. The median nerve of the ox will supply to the caudal and caudo-medial aspects of the digits. You might follow the same method to learn the median nerve of the ox.
The median nerve in a thoracic girdle of ox
The median nerve of ox derives from the ventral branches of the eighth cervical and first thoracic spinal nerves. It crosses the medial face of the axillary artery and forms the ansa axillary with the musculocutaneous nerve of an ox.
The median nerve in the arm region of ox
You will find the median nerve at the medial aspect of the humerus bone of the ox. First, the median nerve runs cranially to the coracobrachialis muscles and then the biceps brachii muscle. Here, you will see the median and ulnar nerve run together within a common covering. At the middle of the humerus bone, the median nerve of ox separates from the ulnar nerve.
The median nerve in the forearm region of ox
You will find the median nerve just caudal or posterior to the radius bone of ox. This nerve is lying in between the flexor carpi radialis and flexor digitorum superficialis muscle.
The median nerve in maneus region of ox
The median nerve runs posteriorly from slightly upper to the carpus of the ox. At the half of the metacarpus bone, the median nerve divides into median and lateral branches. There you will find some other branches that supply to the flexor group of muscles.
The lateral branch of the median nerve gives off the palmar axial digital nerve IV and communicating branch in ox. This communicating branch of the median nerve joins directly with the palmar branch of the ulnar nerve (I will show you in the ulnar nerve section). It forms the palmar common digital nerve IV (abaxial).
Okay, let’s come to the main branch of the median nerve of an ox. The medial branch runs the palmar aspect of the metacarpus bone and forms the palmar common digital nerve II and III.
The palmar common digital nerve II further divides into palmar proper digital nerve II and palmar digital nerve III (abaxial) at the fetlock joint. In addition, the palmar common digital nerve III supply the digits III and IV. It supplies digit II as the palmar digital nerve III (axial) and digits IV as palmar digital nerve IV (axial).
So, the palmar common digital nerve II supply the caudo-medial surfaces of the digits and the III supply the caudal surface of the digits.
The ulnar nerve from the brachial plexus of ox
Now, I will also show you the course of the ulnar nerve from the brachial plexus of ox. The ulnar nerve of ox supplies to the cranio-lateral and caudo-lateral surfaces of the digits.
I will try to make a concise course of the ulnar nerve for you. But, you might follow the same procedure that was performed in the radial nerve.
An ulnar nerve in the thoracic girdle of ox
The ulnar nerve derives from the ventral branches of eight cervical and first and second thoracic spinal nerves. It descends over the medial surface of the axillary artery and with the median nerve of the ox.
The ulnar nerve in the arm region of ox
At the middle third of the arm, the ulnar nerve inclines caudally and crosses the medial face of the brachial artery. Here, you will also find the brachial vein at the caudal aspect of the ulnar nerve.
It gives the caudal cutaneous antebrachial nerve at the proximal to the point of elbow joint of ox. The caudal cutaneous antebrachial nerve innervates to the caudal aspect of the forearm.
An ulnar nerve in forearm region of ox
The ulnar nerve of ox continues distally caudal to the medial epicondyle of the humerus bone. It descends between the flexor carpi ulnaris and ulnaris lateralis muscles of the ox.
Ulnar nerve in maneus region of ox
Slightly proximal to the accessory carpal bone, the ulnar nerve of ox divides into dorsal and palmar branches. The palmar branch of the ulnar nerve again divides into deep and superficial branches in ox.
The deep branch innervates to the interosseous muscle distal to the carpus of ox. In addition, the palmar branch of the ulnar nerve joins with the communicating branch of the median nerve and forms the palmar common digital nerve IV. Again, it innervates digit V as lateral accessory digital nerve V and digits IV as palmar proper digital nerve IV (abaxial). So, the superficial branch of the ulnar nerve innervates the caudolateral surfaces of the digits of an ox.
On the other hand, the dorsal branch of the ulnar nerve runs between the tendon of flexor carpi ulnaris and ulnaris lateralis muscles. You will find this ulnar nerve palmar lateral in the carpus and dorsolateral aspect of the metacarpus bones.
After passing the carpus and metacarpus of an ox, it becomes a dorsal common digital nerve IV in ox. At the fetlock joint, it divides into two and innervates digits V and IV. It innervates the digit V as lateral accessory digital nerve V and digits IV as dorsal proper digital nerve IV (abaxial).
So, the dorsal common digital nerve IV of ox innervates the cranio-lateral surfaces of the digits.
I tried to show you all the courses in the brachial plexus of ox labeled diagram. If you need a more specific diagram or actual nerve pictures, you may follow the anatomy learner on social media.
Summary of innervation (brachial plexus nerves)
The radial nerve of ox, supply to the digits II, III, and IV (cranial, and cranio-medial surfaces). In addition, the median nerve of ox supply to the digits III, and IV (caudal and caudomedial). Again, the ulnar nerve of ox supplies to the digits IV and V (cranio-lateral and caudolateral).
Blocking of radial, median, and ulnar nerve of ox
You may read this (nerve blocking) article if you want to know the blocking sites for the radial median and ulnar nerve. Here, I will provide a little information about the blocking site of ox’s radial, median, and ulnar nerves.
Radial nerve – at the halfway in between the acromion process of scapula and point of elbow or olecranon process or lateral condyle).
Median nerve – The site is a groove caudal to the radial bone and between flexor carpi radialis and flexor digitorum superficialis muscles.
Ulnar nerve – the site is above the accessory carpal bone of ox.
Common questions for viva
I will enlist some common questions (sample) from the brachial plexus of animals. Try to make the proper answers to the following questions on radial, median, and ulnar nerves.
- Mention the specific location of radial, median, and ulnar nerves at the forearm of an ox
- How is ansa axillary formed?
- Which surfaces and digits are supplied by the radial, median, and ulnar nerves?
Frequently asked questions on brachial plexus.
Fine, in this section of the article, I will try to answer all the reader’s questions. You may also ask anything about the brachial plexus, and I will try to reply.
What is a brachial plexus in anatomy?
In anatomy, the brachial plexus means the plexus of intersecting nerves. It forms with the convergence of the ventral branches of the cervical and thoracic spinal nerves. The number of the cervical and thoracic spinal nerve may vary with the different animal species.
In cattle, the brachial plexus forms by the ventral branches of the last three cervical and two thoracic spinal nerves. Again, in goats, it forms by the ventral branches of the last three cervical and first thoracic spinal nerves.
What is the function of the brachial plexus?
The major function of the brachial plexus is innervating to the muscles and skin of the forelimb of animals. It also innervates the specific parts of the thoracic cavity and the neck of an animal.
What are the branches of the brachial plexus?
You will find almost eleven major branches in the brachial plexus of an animal. Among these branches, the radial, median, and ulnar nerves are more important as they supply animals’ digits. If you want to know all these branches of the brachial plexus, please go to the list above.
What is the pathway of the brachial plexus?
I have already described the pathway of the brachial plexus of the animal. Please read the full article carefully to learn the pathway of the brachial plexus.
Conclusion
I hope you got a basic idea of the brachial plexus of ox with its branches and primary supply from this article. The three major branches of the brachial plexus (radial, median, and ulnar nerves) supply the digits of ox, sheep, and goat. The radial nerve of ox supplies the cranial and cranio-medial surfaces of the digits (II, III, IV). The median nerve of ox supplies the caudal and caudomedial surfaces of digits (III, IV). In addition, the ulnar nerve supplies the cranio-lateral and caudolateral surfaces of the digits (IV, V). I want to remind you again to grab the resource that I provided in this article.
