GENERAL INFORMATION ABOUT INTERCOSTALIS EXTERNAL
The intercostalis external is a group of muscles found in the chest. Specifically, there are eleven on each side of the chest, located between the ribs. They aid in the mechanical aspect of breathing and are responsible for elevating the ribs, thus increasing the volume of the thoracic cavity during inspiration. Consequently, they play a crucial role in the respiratory process.
ORIGIN OF INTERCOSTALIS EXTERNAL
The external intercostal muscles originate from the inferior border of the ribs above. Therefore, their origin points are well-positioned to support their function in rib movement and stabilisation.
INSERTION POINT OF INTERCOSTALIS EXTERNAL
They are inserted into the superior border of the rib below. Thus, their insertion points are essential for facilitating rib movement during breathing.
MAJOR ARTERIES
The major arteries supplying these muscles are the posterior intercostal arteries. Consequently, these arteries ensure that the muscles receive adequate blood flow to perform their functions effectively.
NEURAL INNERVATION
These muscles are innervated by the intercostal nerves, which are the anterior rami of the thoracic spinal nerves. Therefore, proper nerve function is crucial for the activation and control of the external intercostal muscles.
TRIGGER POINT
Trigger points for these muscles can generally be found along the spaces between the ribs. Pain can often be felt in the chest and upper back region. Addressing these trigger points through massage or other therapies can alleviate discomfort and improve muscle function.
CONCENTRIC FUNCTION OF INTERCOSTALIS EXTERNAL
The concentric function of these muscles is to elevate the ribs during inspiration, aiding in breathing. Thus, they are essential for effective inhalation, particularly during deep breaths.
ECCENTRIC FUNCTION OF INTERCOSTALIS EXTERNAL
During forced expiration, these muscles control the rate of lowering the ribs. Consequently, they play a critical role in maintaining stability and control during the exhalation process.
ISOMETRIC FUNCTION
The intercostal external muscles’ isometric function is to maintain the spacing and alignment of the ribs. Therefore, they provide essential support during various physical activities.
RELATED MUSCLES (SCIENTIFIC NAMES)
- Internal Intercostal Muscles: Work in opposition to the external intercostals during forced expiration by pulling the ribs downward.
- Innermost Intercostal Muscles: Similar in function to the internal intercostals, aiding in decreasing the rib cage volume during exhalation.
- Diaphragm: The major muscles of respiration contract during inspiration to increase thoracic cavity volume, working synergistically with the external intercostals.
- Transversus Thoracis: Assists in pulling the rib cage downwards during expiration, complementing the internal intercostals.
- Subcostal Muscles: Located on the lower ribs, these muscles assist in the depression of the ribs, similar to the internal intercostals.
ANTAGONIST MUSCLES
- Internal Intercostal Muscles: Act during expiration to oppose the rib elevating action of the external intercostals, facilitating exhalation.
COMMON INJURIES
- Intercostal Muscle Strain: This can occur from overstretching or excessive force, leading to pain during breathing movements.
- Thoracic Outlet Syndrome involves compression that affects the nerves running between the ribs, potentially impinging on nerves related to the external intercostals.
EXERCISES
- Deep Breathing: This technique utilises the full range of the external intercostals to enhance lung capacity and strengthen these muscles.
- Thoracic Expansion Exercises: Focus on increasing the flexibility and mobility of the chest wall, which will promote better lung expansion.
- Rib Mobility Exercises: Target the ribs specifically to improve their range of motion, which is crucial for effective deep breathing.
- Segmental Breathing Exercises: Concentrate on isolated sections of the chest to enhance localised expansion and control.
- Pilates Breathing Techniques: Integrates breathing with movement, focusing on controlled and expansive thoracic movements.
STRETCHES
- Side Stretches: Target the intercostal spaces, expanding and relaxing the external intercostals.
- Chest Stretches: Open up the anterior aspect of the thorax, improving the range of motion and elasticity of the chest wall.
- Breathing Exercises with Extended Exhalation: Helps to elongate the respiratory cycle, which trains the muscles for more efficient function.
- Yoga Poses for Rib Cage Opening: Examples include the cobra pose and the bow pose, which emphasise stretching and expanding the thoracic region.
- Dynamic Arm Swings: These involve moving the arms in wide arcs to facilitate rib movement and actively engage the external intercostals.
Implementing these exercises and stretches can greatly enhance the function of the external intercostal muscles, leading to improved respiratory health, increased thoracic mobility, and a reduction in the risk of related muscle injuries.