Raise Your Paddle: The Mammalian Rotator Cuff
- Ryan O'Hern
- Feb 29, 2016
- 3 min read
As I work with these animals on the butcher block, I see a mirror of my own anatomy. The muscle groups and Latin names are nearly identical to my own. There are only minor differences in structural anatomy between humans and other four-legged mammals. We are more similar than we are different.
Of course we move across the landscape differently and these species-specific locomotive patterns determine which muscles we rely on the most. As humans we walk on our hind legs and this frees up our arms to do non-locomotive work. Our arms have access to such a dynamic range of motion due to the unique structural design of the shoulder joint and rotator cuff.
The shoulder can move in ways that other joints cannot. The muscles surrounding the shoulder blade allow free movement across the ribcage. Needless to say that the health of these muscles are very important whether you walk on four legs or two. Each muscle has an identity and a function, but collectively they are called the Rotator Cuff.
The Rotator Cuff is only four muscles (supraspinatus, infraspinatus, subscapularis, teres minor). I have included the triceps brachii and teres major in certain photos because they border the rotator cuff.
(Lft to Rt) triceps brachii, teres major, infraspinatus, supraspinatus.
(Lft to Rt) triceps brachii, teres major, infraspinatus, scapula, supraspinatus, (below) subscapularis.
Humans have been encountering the muscles and bones of the animal rotator cuff for as long as they have been hunting and eating these animals. One of the gems of the rotator cuff is the Scapula. It is a long, wide and flat bone that’s hard to miss during the butchering process.
(scapula. paddle bone.)
Ancient humans knew this bone well. It served as a paddle for their fishing boats. It could be fashioned into weaponry or made into jewelry. In many agrarian communities it would be mounted on a stick for use as a “Scapula Hoe.” (link to Scapula Hoe images)
Every day at the butcher block I ponder the details of animal remains. In modern times there are only a few like me, while at many stages of human history every member of society was involved in the work of subsisting on dead animals. I am linked to a time when familiarity with animal bones and tissues was the norm. A time when every man, woman, and child knew where the scapula bone came from, what it was used for, and understood it's value.
Muscles in Order of Most Commonly Injured by Humans:
1) Injury to Rotator Cuff muscles and tendons is very common among humans. The Supraspinatus muscle and tendon is the most likely to get torn or inflamed. It is the most important muscle for moving your arm away from your side (lateral abduction).
2) The Infraspinatus is the next most commonly injured rotator cuff muscle. It works in concert with Supraspinatus, and in addition plays a leading role in externally rotating the arm.
3) Subscapularis lays on the rib cage side of the shoulder blade bone, or “scapula.” It is third most likely to be injured. It’s job is to internally rotate the arm.
4) Lastly Teres Minor (not pictured) is least likely to be injured. It plays a supporting role in external rotation alongside Infraspinatus.
Teres Major is worth mentioning although it is not technically part of the Rotator Cuff. It works together with the Latissimus Dorsi to draw the arm down from an extended position, and depress the scapula.
(There are a number of outstanding exercises that can help strengthen and fortity the human shoulder. The Turkish Get Up is a great one.)
Muscles Ranked by Tenderness:
Flat Iron (infraspinatus&teres minor) is the 2nd most tender muscle on a quadruped animal. All it needs is salt, pepper, garlic, and high heat searing.
Underblade Flap (subscapularis) is the 6th most tender muscle. Though this is very tender, a dry-rub or marinade can enhances it's flavor.
Mock Tender (supraspinatus) is the 25th most tender muscle. It's lack of tenderness is certainly the result of it's frequent use. It could be roasted, but is more enjoyable when brined, dry-cured, or made into jerky.
Comments