This article does not address injuries to the cartilage or ligaments of the gleno-humeral joint, as these are outside the scope of massage therapy and require medical or surgical intervention. This article is about the muscles, kinesiology, and massage treatment of the shoulder/arm muscles.
Let’s start by listing the muscles that surround the shoulder joint and then we will define what constitutes the joint itself.
MUSCLE AND ACCESSORIES:
At the front is the pectoralis major which stabilizes the front of the shoulder by joining the sternum to the clavicle (clavicle) and upper arm (humerus).
There are two pectoral muscles, the second being the smaller. It originates from the 3-5 rib and attaches to the acromion process, which is the protruding finger that sticks out on top of the shoulder blade (scapula).
The muscle that counteracts the pectoralis in the back is the rhomboid major and minor. These muscles originate from the spinous or vertebral border of the scapula and are attached to the sides of the thoracic vertebrae. The rhomboid minor attaches to T1-3 while the rhomboid major attaches to vertebrae T3-5. They slope downward from the inside to the outside of the body, from medial to lateral. Also on the back is the trapezoid. This is a large muscle with three components: upper, middle, and lower. The upper part attaches to the occiput of the head, and as it descends the neck, it makes a turn at the inner corner of the scapula, and then attaches to the outer edge of the scapula. Its participation is to elevate the shoulder-arm complex of the scapula. The middle trapezius assists the rhomboids and is more superficial to the surface. The clasps of the lower trapezius cross the crest of the scapula (shoulder blade) and then continue downward in a diagonal inward direction to the spinous process of the vertebrae and clasps from the 6-12 thoracic. This part of the muscle is used to lower the scapula.
The next most important muscles that are involved with the shoulder are the rotator cuff muscles. These surround the humerus (upper arm bone), are anchored to the scapula, and support the humerus in the glenohumeral socket with ligaments that help provide stability. This joint is loosely packed to allow for the greatest range of motion, as is evident with the 360-degree rotation of the arm.
The anterior rotator cuff muscle originates below the scapula and is called the subscapularis. It attaches to the front of the humerus. The top of the humerus is held in place by the supraspinatus, which originates just above the spine of the scapula and attaches to the top of the humerus. It passes under the hook in the acromion process before joining there. This offers you some protection.
The deltoid muscle covers the shoulder joint and provides the muscle strength needed to fully raise the arm. It is made up of three components, anterior (front), medial, and posterior (back). All three parts of the deltoid work with other muscles around the shoulder to allow circumferential rotation of the arm.
The other posterior muscle of the rotator cuff is just below the spine of the scapula and is called the infraspinatus. It covers the lower outer (dorsal) part of the scapula and attaches to the posterior part of the humerus near the joint capsule.
Another muscle that opposes the rhomboids is the serratus. It attaches to ribs 5-9 on the side of the body and attaches below the scapula to the vertebral border. When contracted, it extends the shoulder blade outward. The opposite movement of retraction is produced by the contraction of the rhomboids. Sometimes the serratus can become tight due to excessive protractive repetitive motion, eg golfing, batting, etc.
Beneath these muscles, the gleno-humeral (shoulder) joint is enclosed in a synovial joint capsule and surrounded by ligaments posteriorly, superiorly, and frontally. However, the weakest point of the joint is the front, and after tearing the frontal ligaments, the arm can dislocate and bulge more severely anteriorly (towards the front) with a sufficiently strong impact to the torso or arm. Oh!
Two other major muscles that surround the shoulder joint are the biceps brachii and the triceps. Both muscles are at the front and back, respectively, of the humerus or upper arm. The biceps brachii in front has two shoulder attachments, one short and one long. The short is attached to the front of the scapula and the long to the top via a long tendon. The arm also has brachio-radialis and brachialis which are on either side of the biceps brachii and which help the arm to flex. They also attach to the front of the scapula and provide some strength to the arm and shoulder joint.
On the back of the arm is the lattisimus dorsi which helps to extend the arm backwards. It attaches to the inner front of the arm near the gleno-humeral joint of the shoulder and passes under the arm, through the armpit, and joins the ribs on the scapular side and over the scapula.
The teres minor and major are both arm rotators. Both the teres minor and teres major attach to the arm and outer edge of the scapula.
The teres major attaches under the axilla to the front of the humerus next to the latissimus dorsi and internally rotates the arm when contracted.
The teres minor attaches to the upper back of the arm and when contracted rotates the arm outward.
So let’s add up all the muscles we’ve listed so far to see how many we have. Pectoralis major, pectoralis minor, rhomboid major, rhomboid minor, trapezius, serratus, subscapularis, supraspinatus, infraspinatus, biceps brachii, triceps, brachiradialis, brachialis, latissimus dorsi, teres minor, teres major. That makes sixteen muscles.
KINESIOLOGY – MOVEMENT OF THE SHOULDER JOINT
The movement of the arm over the shoulder works in many planes and axes. The axes are x, y, and z.
The ‘X’ axis is the easiest to learn as it moves the arm from front to back, or sagittally (the sagittal plane is a front to back cross section that divides the body from left to right). When the arm moves from the side forward toward the head, it is called flexion. When the arm moves back behind the body it is called extension. The muscles involved in flexion are the antero-anterior muscles: biceps, brachialis, radio-brachialis. The muscles involved in the extension are the latissimus dorsi and the triceps.
The ‘Y’ axis involves movement of the arm along the frontal plane (the frontal plane cuts the body from front to back vertically), from the resting side to abduction raising the arm to the top of the head. The muscles involved are the supraspinatus, deltoid, and trapezius. When the arm crosses the chest in horizontal adduction, the muscles involved are the pectoralis major, pectoralis minor, serratus, and anterior deltoid.
The ‘Z; axis implies the movement of the arm rotation. With the arm fully extended and raised to shoulder height, the ‘z’ axis runs through the body from the left arm to the right arm. When the arm is internally rotated, starting with the palm facing forward and the thumbs facing up, rotating the arms until the thumbs are facing down and the palms facing back, the muscles involved in this movement are the teres major and some of the dorsi. broad.
When rotating backwards or outwards, the muscle involved is the teres minor.
Rotator cuff stabilizers:
While these aforementioned muscles move the arm through its range of motion, the rotator cuff muscles stabilize the arm by holding it tight at the gleno-humeral joint. There are three main muscles of the rotator cuff: the supraspinatus, at the top that also raises the arm. The subscapularis, which is below the scapula (shoulder blade), the infraspinatus above the scapula, and the teres minor to a lesser degree due to their attachments, offer less stabilization than the other three muscles, but can be considered an accessory.
Due to the loose nature of the shoulder joint, which means that because the joint is shallow, there is maximum flexibility and movement of the joint, as can be experienced when performing a 360 degree rotation of the arm, either in flexion or extension.
Although it is not without some amount of resistance that this movement is performed because there are always antagonists to the agonists, that is to say: the agonists are the muscles that contract while the antagonists are the opposing muscles that relax. So it is quite a complex feat that when we circumrotate the arm we do not experience pain or limitations of movement.
Which is precisely what we experience when we have a shoulder injury or limitation that causes pain.
MASSAGE TREATMENTS
In my practice as a massage therapist at a fitness center, I have found that most shoulder injuries involve tendinitis, bursitis, and muscle contractures and adhesions.
All four types of injuries result from the repetitive nature of weight training or strengthening. Excessive stress is placed on tendons, bursae, and muscles, causing inflammation, tearing, bursa compression, and repeated muscle contractures and resulting adhesions.
Tendonitis and bursitis can only be cured by stopping exertion and applying ice to alleviate the inflammation process. Muscles can be treated for contractures and adhesions with massage.
Often gym clients refuse to modify or reduce their weight training to alleviate the injury and persist in training despite pain which magnifies their injury and pain. Those who choose to stop their weight training long enough for the inflammation process to subside and heal have a good or complete recovery.
I use general massage techniques on the pectoralis, deltoids, latissimus dorsi, biceps and triceps and other superficial muscles that surround the shoulder joint. This allows me to pay attention to the rotator cuff muscles. What I can do is reduce muscle tone, work on some contractures and adhesions in the deltoid and pectoral muscles and the rotator cuff, taking the tension off the tendons and bursae. Then time heals with a greatly reduced weight training regimen or complete termination of weight training until inflammation of the tendons and bursae occurs, which can take anywhere from one to four weeks depending on the severity of the tendinitis/bursitis.
I have found that weekly massage treatments of half an hour to an hour, depending on the client, are adequate for the complete treatment of this condition.