Skip to main content

📌 CLINIC NEWS & UPDATES: 👇🏽

Todays Trending Topic ♛

Environmental Factors Behind Thyroid Disease | Wellness Clinic

The thyroid gland is a butterfly-shaped organ located in the base of the neck. It's in charge of releasing essential thyroid hormones which control the body's metabolism, the way the body uses energy. The thyroid gland's hormones regulate vital body functions, such as breathing, heart rate, central and peripheral nervous systems, body temperature and more.

What causes autoimmune thyroid disease?
As essential as the thyroid gland is, however, the body's own immune system can sometimes malfunction and attack this important endocrine organ, ultimately affecting its function. Autoimmune thyroid diseases, like Hashimoto's thyroid disease and Graves' disease, have been on the rise in the United States. While the diagnosis of thyroid disease has increased, many doctors still don't know the cause of the issue, but these have been linked to several factors.

Environmental Factors for AITD
A number of environmental factors have been associated with the development an…

Shoulder Pain Caused by Serratus Anterior Injuries

Shoulder Pain Caused by Serratus Anterior Injuries - El Paso Chiropractor


Shoulder pain is a common complication which affects many athletes who participate in overhead sports, such as swimming, tennis and other throwing sports. Overhead, physical activities primarily utilize upper extremity movements that place tremendously high demands on the structures of the shoulder as these often require increased muscular activation around the scapula-thoracic joint and the glenohumeral joint. Researchers from previous studies determined that abnormal biomechanics of the shoulder girdle and constant or repeated overhead movements can lead to injuries in overhead throwing athletes.
blog picture of anatomical shoulder pectoralis major rupture
Share Free Ebook
Particularly, muscular imbalances around the complex structures of the shoulder can develop abnormal activation patterns and inherent myofascial restrictions, both which can cause a significant decrease in the athlete’s scapular control and dyskinesis, leading to glenohumeral joint injuries resulting from instability and impingement.
The serratus anterior, or SA, is one of the muscles of the scapula that functions by providing a connection between the shoulder girdle and the trunk, however, it’s often believed to be a dysfunctional muscle among shoulder pathologies. The serratus anterior is a primarily offers movement to the scapula, contributing to the maintenance of normal scapulo-humeral rhythm and motion. Due to its insertion on the inferior and medial border of the scapula, it can produce upward rotation and posterior tilting. Poor activation of the serratus anterior muscle may result in limited scapular rotation and protraction, causing a relative anterior-superior translation of the humeral head in relation to its glenoid articulation, leading to sub-acromial impingement and rotator cuff tears.

Serratus Anterior Diagram - El Paso Chiropractor

Anatomy of the Serratus Anterior

The serratus anterior is characterized as a flat sheet of muscle beginning from the lateral surface of the first nine ribs. Then, it passes behind and around the thoracic wall before inserting into the anterior surface of the medial border of the scapula. The most important function of the serratus anterior, or SA, is to protract and rotate the scapula, helping to maintain it close yet away from the thoracic wall, allowing for the proper positioning of the glenoid fossa to increase the efficiency of upper extremity motion to its maximum state. The anatomy of the SA can be broken down into three anatomical components as follows:
First, the superior component of the serratus anterior begins from the first and second ribs, which then inserts into the superior medial angle of the scapula. This fundamental section serves as the anchor that allows the scapula to rotate when the arms are lifted overhead. These fibres run parallel to the 1st and 2nd rib;
Second, the middle component of the SA begins from the second, third and fourth ribs, which then introduces into the medial border of the scapula anteriorly, in between the scapula and ribs. This basic part is essential for the protraction muscle of the scapula;
And last but not least, the inferior component of the serratus anterior originates among the fifth to ninth ribs and inserts on the inferior angle of the scapula. The fibres within this region are designed to form an arrangement similar to a quarter fan, which then implants onto the inferior border of the scapula. This third and last portion serves to both protract the scapula and rotate its inferior angle upwards and laterally. It’s been previously proposed that the lower section of the serratus anterior carries out the stability of the inferior border of the scapula, also functioning with the lower trapezius to create a simultaneous force to upwardly rotate the scapula during overhead movements for specific sports and physical activities.
Essentially, the serratus anterior primarily operates to upwardly rotate the scapula during shoulder abduction, principally from 30-degree shoulder abductions onwards, it also stabilizes and protracts the scapula during shoulder flexion movements, rotates the inferior angle, or the posterior tilt, of the scapula, balances the scapula against the thorax during forward pushing movements to prevent the abnormal function of the tissues, and it also functions to firmly hold the medial border of the scapula against the thorax to ensure that it can change the thorax posteriorly during a push up with the hands fixed.

Serratus Anterior with Thoracic Nerve - El Paso Chiropractor

For an athlete, certain movements in particular with their specific sport or physical activity can require a high level of function from the SA in order to achieve either full scapular protraction and/or upward rotation. Examples of athletic performances requiring the function of the serratus anterior include: throwing a punch in boxing to achieve maximum reach of the arm. Because of this, the SA is frequently referred to as the boxer’s muscle. Among boxers, the serratus anterior is crucial for the scapula to be able to brace on impact with the punch, allowing for maximum transfer of force from the lower limbs into the torso for it to transmit into the upper limb and punch. If the scapula were to collapse from the impact of a punch, the boxer would then lose power in their punch. In swimmers, a full upward rotation is necessary for the athlete to achieve a maximum reach in the water upon hand entry in freestyle and butterfly swimming. An overhead athlete, such as a tennis player, utilizes a full upward rotation when serving. Among the sweep style rower, the athlete needs full protraction on the longer region to achieve the required reach during the catch phase of the rowing stroke. And in baseball, for example, the pitcher requires high levels of protraction to follow through with a pitch, similarly, in the throwing events in athletics.
The long thoracic nerve can be found within the serratus anterior, which originates from the fifth, sixth and seventh cervical nerves. These nerves then pass through the scalenus medius muscle before they another cervical branch of nerves which travels through to the scalenus medius as well. The long thoracic nerve then passes through the brachial plexus and the clavicle to pass over the first rib. In this section, the nerve enters a fascial sheath and continues traveling along the lateral feature of the thoracic wall through the serratus anterior muscle.  

SA Dysfunction & Scapula Dyskinesis

The proper positioning of the humerus within the glenoid cavity, best referred to as the scapulo-humeral rhythm, is essential towards the proper function of the glenohumeral joint during overhead movements. Any alterations in the normal motion of the scapula may cause an inappropriate positioning of the glenoid relative to the humeral head, causing injury to the SA due to impingement and instability and resulting in shoulder pain and other symptoms. The right use of muscle activation and the adequate levels of muscle recruitment are also needed to position the scapula in the proper position. Small changes in the activation of the muscles around the scapula can affect its alignment as well as the forces involved in upper limb movement. The serratus anterior is one of the primary muscles responsible for maintaining normal rhythm and shoulder mobility.
Several healthcare professionals have helped reduce the pain caused by impingement by actively repositioning the injured individual’s scapula into a proper posture by reducing its anterior tilt, increasing the strength of the shoulder during overhead activities. The SA is a muscle that actively functions to position the scapula into posterior tilt during specific sports involving overhead motions.
If there is a lack of strength or endurance in the SA, the muscle also allows the scapula to rest while in a downwardly rotated and anterior tilted position, causing the inferior border of the structure to become more distinguishable. Moreover, an imbalance between the serratus anterior and the other muscles surrounding it, such as the pectoralis minor, may result in what is known as a winging scapula. Scapular winging may speed up or contribute to the development of constant symptoms among athletes with orthopedic shoulder pain and injuries.
Scapular winging can be identified by observing the position of the scapula during a push up exercise. Often, if the winging is due to a muscle imbalance and the primary scapula stabilizer is the pectoralis minor, this will generally correct itself if the individual is asked to protract their scapula. If the wing disappears then the cause is most likely muscle imbalance and if it remains, then it may be a pathological inhibition of the SA. Other instances of scapular winging can also occur due to pathological damage or injury to the long thoracic nerve found within the serratus anterior muscle.

The Significance of the SA

The necessary conditioning of the serratus anterior muscle among an athlete has been previously evaluated in studies regarding sports such as swimming, throwing, and tennis. A fatigued SA muscle can ultimately reduce the rotation and protraction of the scapula, which allows the humeral head to change, most commonly leading to secondary impingement and rotator cuff tears. Further studies on the role the serratus anterior plays in shoulder pathologies has also been analyzed by many other researchers. Some of the most important and noteworthy key points have been summarized and recorded by researchers as follows:
While the researchers conducting these studies evaluated the trapezius and serratus anterior among individuals suffering from shoulder pain and injuries, it was compared with those without damage or injury to the shoulder, and it determined that the upper trapezius can demonstrate increased activity during the raising and lowering of the arm. The results show how the SA can decrease activation at some elevation angles.
Then, the study also evaluated the muscle activation patterns of swimmers with shoulder pain, comparing it to those without, and found that the middle and lower serratus anterior decreased activity in all phases of swimming motion. This can be a possible cause for shoulder pain or other complications where the swimmer uses compensatory muscle activation patterns.

Scapular Winging & Winging Correction #1


Scapular Winging & Winging Correction - El Paso Chiropractor Scapular Winging & Winging Correction - El Paso Chiropractor

Similarly, other researchers have identified an inactivity or activation delay in the SA surrounding the painful shoulders of swimmers while they raise their arms in the scapular plane. It’s also been previously hypothesized that individuals with decreased serratus anterior activations have a closer association with an increased chance of developing shoulder pain and/or instability while the increase in lower trapezius activity may function to compensate for decreased serratus anterior activation. Other studies relating to various types of shoulder dysfunction, found decreased serratus anterior activity and increased upper trapezius activity, without a change in lower trapezius activity among subjects with shoulder injuries when compared to subjects without shoulder complications.

Scapular Winging & Winging Correction #2


Scapular Winging & Winging Correction #2 - El Paso Chiropractor Scapular Winging & Winging Correction #2 - El Paso Chiropractor

The specific position of the scapula has also been associated with the rotator cuff’s ability to function effectively. An excessive anterior tilt of the scapula, an internal rotation or an excessive elevations of the acromion are elements which can decrease rotator cuff activations, ultimately causing insufficient handling of tension along the tendons. These circumstances can debilitate the length-to-tension ratio of these muscles, leading to the loss of stabilization and an increasing risk of muscular disruption or degeneration within the serratus anterior or other tissues surrounding the shoulder. It’s been demonstrated that the function of the rotator cuff can improve the functioning of the scapula muscles, primarily the SA and lower trapezius.

Exercises for SA

A considerable amount of research has been conducted to find the best rehabilitation exercises for serratus anterior muscle damage or injuries. The majority of these studies analyzed the specific movements performed during push-ups, push-up-plus exercises and cable/dumbbell punch type movements. These exercises basically emulate the function of the SA in its protraction role. The studies noted several important findings.
First, resistance was applied with eight scapulo-humeral exercises performed below shoulder height that target the SA muscle in order to design a progressive rehabilitation plan of serratus anterior muscle exercises along with training. According to these researchers, the best exercises are push-ups, dynamic hugs, scaptions and SA punch exercises.   
The studies are found interesting effects of vibration on the activation of the serratus anterior muscles and found that the push-up plus exercise performed increased SA muscle activity. Additionally, the effects of an unstable surface on the upper and lower parts of the SA while performing variations of the push-up exercises were evaluated and the results indicated that different parts of the serratus anterior have distinct functions towards the stabilization process of the muscle. The authors of the study concluded that the main role of the lower SA is the fixation of the scapula onto the thoracic wall. Furthermore, they recommended athletes should perform the push-up plus on an unstable surface as a more effective strategy for the specific mobilization of this component of the SA.
The following exercises are examples of clinically used serratus anterior activation exercises which have been proven to increase the levels of function.

Shoulder Strengthening



The above shoulder strengthening stretches and exercises can also help strengthen the muscles surrounding the shoulder which can help prevent injuries and other complications common among many athletes. Performing the following stretches and exercises can be beneficial towards the rehabilitation of damage or injury to the serratus anterior muscles. Before participating in any form of physical activity after suffering an injury, make sure to consult a healthcare professional on the recommended workout routines for each individual.

Wall Slider


Wall Slider - El Paso Chiropractor Wall Slider - El Paso Chiropractor

To perform this exercise, using a foam roller or pool noodle on the wall, place the wrists against the roller with the forearm in a neutral starting position. Then, protract the scapula so the space between the shoulder blades fills with an increase in thoracic kyphosis. Slowly flex the shoulder so the roller moves up the wall, making sure to supinate the forearms, to reach as high as possible into shoulder flexion. The finish point is when the little fingers touch and the forearm is in maximum supination. Slowly descend and return to the starting point. Perform three sets of ten repetitions.

Swiss Ball Rotations


Swiss Ball Rotations - El Paso Chiropractor

The athlete can perform this exercise by holding a Swiss ball between the arms with the ball gently resting on the chest while the forearms are in a neutral position. Then, slowly rotate the trunk to the left. The arms will glide around the Swiss ball. As the arm protracts, slowly rotate the palm upwards to encourage supination of the forearm and external rotation of the shoulder. Return to the start positions and start again.

TrX Serratus Rollout


TrX Serratus Rollout - El Paso Chiropractor TrX Serratus Rollout - El Paso Chiropractor

The individual participating in the exercise should first place the forearms through the loops of a TrX or other suspension device, placing the straps at wrist level or just below the elbows to differentiate the exercise load. The start position is similar to that of the wall slider above followed by slowly flexing the shoulder to elevate the arms above the head while slowly externally rotating the shoulder by supinating the forearms. The finish position is when maximum flexion/elevation is achieved and the little fingers touch. Return to the start position and perform three sets of fifteen repetitions.

TrX Push Up Plus


TrX Push Up Plus - El Paso Chiropractor TrX Push Up Plus - El Paso Chiropractor

The athlete participating in the exercise should first position the handles on a TrX about two to three feet off the ground. Holding the handles in a push-up position, slowly perform a push up and slowly screw the hands into supination and shoulder external rotation. At the top of the exercise movement, protract the scapula and fill in the space between the shoulder blades with a slight thoracic kyphosis. Return to the bottom position and perform three sets of ten repetitions.
In conclusion, the serratus anterior, or SA, is a muscle that plays an essential role in the movement and control of the scapula during pushing movements and overhead activities. Specifically, it is a protractor, upward rotator, posterior tilt muscle of the scapula and additionally, it fixes the scapula against the rib cage during movement. Ultimately, It is a crucial muscle for the overhead athlete as dysfunction in this muscle can lead to shoulder injuries such as impingement, rotator cuff tears and performance issues during overhead tasks.


By Dr. Alex Jimenez

Today's Chiropractic

Trending: Back Pain Insights

Location Near You

MEET THE STAFF