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Hawk m.

Hawk m.

Have you ever wondered what was under the shoulder blade, aka. scapula of the dog? What is that broad flat muscle under there? What does it do? Is that what holds the scapula in place? If it is, does it affect how the scapula moves? Why would the scapula sometimes feel rigid in place; and other times, like it’s slip sliding away? (Did I just make another Simon and Garfunkel reference? Cecilia!) What happens if the muscle spasms? What can we do to calm it? What else does this muscle do?
 
The muscle that we are describing is a large, flat muscle group, the serratus ventralis m. Its primary function it to connect the scapula to the neck and to the ribs. Theserratus ventralis m. creates a fascial “sling” in which the trunk is supported. This muscle also depresses the scapula, pulls it forward and down, thereby carrying the shoulder forward and backward with respect to the forelimb
 
In a recent Trigger Point workshop with Ken Bain, we learned that this muscle is essentially the dog’s landing gear. The serratus ventralis is the muscle that transfers the weight of the body to the shoulder while the dog is standing; and when the dog jumps down and lands hard on his forelegs, it works as a shock absorber. 
 
And, any movement of the shoulder is dependent on the mobility of the “scapula, relative to the trunk,” so my notes remind me. [http://cal.vet.upenn.edu/projects/grossanat/general/test/smanswerkey.htm]
 
The serratus ventralis gets its name from having the shape of a saw. The Latin term for saw is serrare. A saw is flat, wide and has a jagged, zigzag edge. Ventralis comes from its location; it is ventral, or beneath, the scapula. 
 
The serratus ventralis is a beautiful muscle to behold. It appears to resemble the magnificent spread wings of a hawk. And like the hawk it has the ability to lead and influence movement. The hawk signifies initiative and activity. How appropriate for the muscle that is responsible for movement and stabilization of the front end. 
 
Imagine the tapered feathers of the broad wings originating on the transverse processes of the five lower cervical vertebrae, C3-C7 and also on the ventral (lower) halves of the first seven ribs, T1-T7. These are the tips of the wings of this flat powerful, muscle beneath the scapula. From its five cranial origins they reach back, and from its seven caudal origins they reach forward to insert on the medial dorsal (middle upper) face of the scapula.
 
When the serratus ventralis is in optimal wingspread, the muscle is tightly affixed to its origins, and holds the scapula to the trunk. 
 
The multiple origins on the cranial wing are innervated by ventral branches of the cervical spinal nerves. The multiple origins on the caudal wing, are innervated bythe long thoracic nerve (C7). 
 
This is significant for canine massage and especially for Trigger point work because the points that get, as Ken says, “all jacked up,” are all at neuromuscular junctions. He knows. He has spent the last decade mapping them out with sporting dogs at competitions and his private clients.
 
We know that when muscles flex, they shorten. When any of these points at the muscle bellies or attachments are spasming, they are stuck in a perpetual state of flexion. Trigger point work uses compression on the point that is “triggering” the dysfunction. The type of compression that we learned sedates the function at the junction, so that the energy can flow through.
 
How can you tell if any of the points on either wing is spasming? Identification comes from observing and measuring Range of Motion of the scapula. We check flexion and extension of the shoulder, identify possible triggers in the neck and sides of the ribs, and after sedating points that appear to be excited, recheck Range of Motion. Invariably, we see a measureable increase. Note: the Range of Motion that we are assessing is before the dog moves into an involuntary stretch that might warm the muscles.
 
What else does this muscle do? Along with another group of serrated muscles, the external intercostalis m., it aids in respiration. It also is a protective armor that supports the thorax. And, the high point of the scapula is the measurement used for the height of the dog.
 
PetMassageTM offers 2 home study courses in canine anatomy. 
Basic Anatomy of the Dog http://petmassage.com/?product=basic-anatomy-of-the-dog-distance-learning-course 
Medical Terminology, Canine Physiology, Kinesiology and Pathology for the Canine Massage Practitionerhttp://petmassage.com/?product=medical-terminology-canine-physiology-kinesiology-and-pathology-for-the-canine-massage-practitioner
You can see that we take a more spiritual interpretation of even the driest of anatomy instruction. Bring us your feathers, your pendulum, and your book of huddled totems. Come learn with us. We make learning fun!
The graphic shown here is fromhttps://classconnection.s3.amazonaws.com/940/flashcards/3852940/png/capture-1414C8D9A6B341C4B83.png 

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