Exploring Thoracic Mobility and Breathing Biomechanics

Introduction:

Thoracic mobility, the ability of the ribcage to move and expand plays a pivotal role in the mechanics of breathing. The thorax serves as the protective housing for vital organs while accommodating the intricate interplay between the respiratory and musculoskeletal systems. In this article, we delve into the profound relationship between thoracic mobility and breathing biomechanics, highlighting its significance for Natural Therapists.

Breathing biomechanics refer to the physiological and mechanical processes involved in the act of breathing, which is essential for providing oxygen to the body’s cells and removing carbon dioxide. Breathing involves the coordination of multiple anatomical structures and muscles, and understanding the biomechanics is crucial in order to identify dysfunctional breathing patterns and to develop specific treatment interventions.

Breathing involves two main phases: inhalation (inspiration) and exhalation (expiration).

Inhalation (Inspiration): During inhalation, the diaphragm and external intercostal muscles contract. The diaphragm moves downward, increasing the volume of the thoracic cavity. The external intercostal muscles between the ribs also contract, lifting the ribcage upward and outward. These actions collectively expand the thoracic cavity, causing a decrease in intra-thoracic pressure. This decrease in pressure relative to the atmospheric pressure causes air to rush into the lungs.

Exhalation (Expiration): Exhalation can be passive or active. In passive exhalation, the diaphragm and intercostal muscles relax, and the elastic recoil of the lung tissue, along with the relaxation of the ribcage, decreases the volume of the thoracic cavity. This results in an increase in intra-thoracic pressure, causing air to flow out of the lungs. In active exhalation, such as during exercise, the internal intercostal muscles and abdominal muscles can also contract to actively push air out.

The primary muscles involved in breathing are:

• Diaphragm: A dome-shaped muscle that separates the chest cavity (thoracic cavity) from the abdominal cavity. Contraction and relaxation of the diaphragm control the volume of the thoracic cavity.

• Intercostal Muscles: These are muscles located between the ribs. The external intercostal muscles aid in inhalation by lifting the ribcage, while the internal intercostal muscles assist in active exhalation.

• Accessory Muscles: These muscles, including the sternocleidomastoid, scalenes, pectoralis minor and certain muscles of the back, can become more active during heavy breathing or in conditions of increased respiratory demand.

The lungs themselves have elastic properties due to the presence of elastin fibers and the surface tension of the fluid lining the alveoli (tiny air sacs in the lungs). The elastic recoil of the lungs plays a crucial role in passive exhalation. Surfactant, a substance secreted in the alveoli, reduces surface tension and prevents the collapse of alveoli during exhalation.

Thoracic Mobility and Breathing:

Adequate thoracic mobility is essential for efficient ventilation. Physical restrictions in the thoracic spine or ribcage can hinder the diaphragm’s movement and limit the ribcage’s expansion, leading to lack of diaphragmatic involvement and upper respiratory compensation.

Different activities and situations can lead to varied breathing patterns. For example, during rest, breathing tends to be slow and shallow. During exercise or physical exertion, the body requires more oxygen, leading to faster and deeper breaths, which in turn provides the mobility and endurance required to maintain good breathing mechanics.

Emotions, stress, and certain medical conditions can also influence breathing patterns. These can manifest into altered breathing mechanics and over time cause pain and discomfort associated with cervical spine conditions. Psychological trauma, prolonged anxiety and stress or an overactive sympathetic nervous system can result in these conditions becoming apparent.

Pain may also contribute to dysfunctional beathing. High levels of pain, movement avoidance or movement that causes pain may force the patient to adapt their breathing patterns.

Limited thoracic mobility may force the body to rely more on accessory muscles for breathing, which can result in increased strain and fatigue. Over time, this can contribute to musculoskeletal imbalances and discomfort. The pattern built up over time represents a vicious cycle. Often patients will seek treatment to the painful area which can provide temporary relief. However, treating the symptoms may not resolve the condition and leaving patients seeking unnecessary ongoing treatment.

Assessment and Interventions:

Natural Therapists can employ various strategies to assess and improve thoracic mobility and breathing. Palpation and range-of-motion tests can provide valuable insights if breathing dysfunction is suspected. Patients with breathing dysfunction may present with hypertonicity within the accessory musculature of inhalation which is typically the primary location of their presenting symptoms.

However, there is a direct correlation to the range of motion of the thoracic spine and ribcage and utilisation of the lower thorax in breathing. Assessing thoracic mobility involves observing the range of motion, symmetry and ability to move all parts of the thoracic spine. Assessment of the ribcage movement during breathing, assessing joint mobility, and identifying asymmetries also forms part of a comprehensive assessment strategy.

Treatment Strategies:

Addressing breathing dysfunction requires a comprehensive and individualised approach, often involving collaboration among various health professionals. An evidence-based model that addresses the underlying condition and involves the patient in the decision-making process as much as possible should be used. Below are a number of different treatment approaches that may be used for patients that exhibit breathing dysfunction.

Education, Mindfulness and Biofeedback:

Education can be one of the most powerful treatment interventions. Patients must be informed of the importance of proper breathing techniques and how breathing dysfunction can impact their overall health. A step-by-step approach to breathing focussing on the lower thoracic and diaphragmatic movements can have a profound effect. Explaining the connection between stress, anxiety, and breathing patterns and teaching relaxation techniques, mindfulness, and stress management strategies are an integral part of the overall treatment strategy.

Breathing exercises should encourage slower, diaphragmatic breathing instead of shallow chest breathing. This can be achieved by the patient placing one hand on their belly and the other hand on their chest and observing which hand rises first or is dominant. This biofeedback strategy can be progressed to using a book or other moderately heavy object on the patient’s belly. The focus should be on diaphragmatic breathing which should move or press into the hand (or book) which is further validated visually. Breathing apps and wearable devices can also provide real-time feedback to encourage proper breathing techniques.

Lifestyle, Occupational and/or Behavioural Modifications:

Once the patient is able to master diaphragmatic breathing, it should be incorporated into activities of daily living, exercise or specific mobility techniques to further consolidate the pattern.

For patients with breathing dysfunction related to anxiety or panic disorders, Cognitive Behavioural Therapy can help address underlying psychological factors and modify maladaptive thought patterns. Further, the importance should be emphasised on the ability of the patient to recognise their breathing patterns and identify when sub-optimal biomechanics are utilised.

Patients should also be advised to quit smoking, maintain a healthy weight, and engage in regular moderate to high intensity physical activity to improve overall respiratory health.

Mobility and Preventative Training: Mobility exercises should encompass thoracic extension, rotation, lateral flexion, and ribcage expansion. Techniques such as thoracic spine mobilisation, foam rolling, and dynamic stretches can be effective. Incorporating breathing exercises that encourage deep diaphragmatic breathing can aid in improving thoracic mobility.

Some examples include an ‘Open Book’ exercise with deep breathing or a ‘Quadruped Reach’ or ‘Thread the Needle’ exercise. These are all beneficial when implemented gradually with deep breathing awareness.

Treatment strategies should be tailored to the individual patient’s needs, underlying conditions, and contributing factors. A holistic approach that combines education, retraining, psychological support, and medical interventions often yields the best outcomes for addressing breathing dysfunction.

Conclusion:

The intricate relationship between thoracic mobility and breathing biomechanics underscores its importance in maintaining optimal health and functionality. Health professionals, armed with a comprehensive understanding of this connection, can employ targeted interventions to enhance thoracic mobility, thereby positively impacting breathing mechanics and overall wellbeing. Through a holistic approach that combines assessment, exercise, and education, health professionals can empower their patients to achieve better respiratory function and a higher quality of life.

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