Breathing dysfunctions

Two common abnormalities: "Open Scissors Syndrome" and the "Hourglass Syndrome".

IAP is the pressure in the abdominal cavity that enables us to stabilize our core, allowing our limbs to move correctly. This pressure is generated by various muscles, fascia, and tendons, such as the diaphragm, pelvic floor, and abdominal wall muscles. Therefore, it's essential to note that IAP is a vital prerequisite for any movement and is the primary stabilizer of the trunk and pelvis.

In a previous article, we addressed the theoretical aspects of breathing biomechanics, including the impact of intra-abdominal pressure (IAP) on spinal stability and its significance as a prerequisite for all movements. In this article, we will discuss two respiratory dysfunctions, namely, Open Scissor Syndrome and Hourglass Syndrome. If you haven't read the prior article about IAP, I recommend doing so before continuing with this one.

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In today's world, our lifestyle, environment, and various types of stress can cause issues with the way our body is structured. This can lead to abnormalities in the sequence of co-activation between different structures, especially when it comes to breathing. In a correct structure, breathing is like a cylinder, with the abdominal wall expanding three-dimensionally in all directions. However, in an incorrect structure, the pelvic floor and the diaphragm may not be aligned, which can cause various structures in the core to be in an eccentric and concentric orientation, resulting in suboptimal functioning. Two common abnormalities are the "Open Scissors Syndrome" and the "Hour Glass Syndrome".

Open Scissors Syndrome:

Pavel Kolar coined the term "postural syndrome," but it is also known by various other names in literature. Czech neurologist Vladimir Janda called it "lower cross syndrome" (LCS), and Ron Hruska, the founder of Postural Restoration (PRI), referred to it as the "posterior extensor chain" (PEC). Richard Ulm named it the "extension compression stabilization strategy" (ECSS). Despite the different approaches, they all refer to a muscular imbalance and poor communication between the pelvic floor and the diaphragm. This instability can occur due to functional, structural, or neurological reasons.

According to Janda, LCS occurs due to a muscle imbalance between weak and tight muscles. The hip flexors and erector spinae are typically the tight muscles, and the abdominals and gluteal muscles are the weak muscles. Hruska's approach is similar to Janda's, with the difference being that he interprets the changes in muscle function as a result of a positional change of the structures. Kolar, on the other hand, has a different approach and defines the muscles as tonic (lumbar erectors, hip flexors, adductors, levator scapulae, and the pectoral group) and phasic (serratus anterior, abdominal wall, gluteals, and the deep neck flexors). During the first year of life, the CNS undergoes many changes. At the beginning of this maturation, tonic muscles play a key role in trunk stabilization and limb differentiation. During this process, the phasic muscles are activated only at a later time and ensure that the primary function of tonic muscles becomes stability, whereas the phasic muscles are responsible for movement.

However, maintaining the function of phasic muscles is often more complicated than that of tonic muscles, and their late development is also probable. As a result, the phasic muscles in our human body become inhibited, and the tonic muscles become the primary movers of the human body. According to some research, this inhibition occurs when a threshold called the "functional threshold" is exceeded, where intensity, volume, and fatigue play a key role in overcoming it. The hypertonicity of tonic muscles and inhibition of phasic muscles result in the postural syndrome of Open Scissors Syndrome (Figure 1). In the article above, I explain how this proximal stability can lead to changes distally and how we can approach the issue with exercises.

Figure 1: The Open Scissor Syndrome and the crossed connection of the muscles of Janda

Hourglass Syndrome:

The Hourglass Syndrome is a condition characterized by postural hyperactivity of the rectus abdominis and upper parts of obliques. This muscular imbalance within the core is caused by suboptimal timing between these muscles. There are three main causes of Hourglass Syndrome: early childhood development, post-injury/trauma, and anxiety-driven societal aspects. When observing the muscle tone distribution and contour of the abdominal wall, it should be fairly relaxed when standing. However, an "hourglass syndrome" can be observed, especially in women. For aesthetic reasons, some women perform hollowing of the abdominal wall, which compromises both stabilization and breathing patterns.

The diaphragm is a crucial respiratory muscle that serves as a stabilizer and sphincter. All three of these functions are interdependent, and their dysfunction in one aspect can compromise the others. The biomechanics of breathing play a fundamental role in postural problems, and training for an ideal posture goes hand-in-hand with breathing pattern training. During inhalation, the diaphragm moves downward through a concentric contraction, which expands the lower ribs laterally. The antagonists of the diaphragm, the abdominal wall, work eccentrically, causing an increase in the intra-abdominal pressure (IAP). The opposite happens during exhalation. In this phase, the diaphragm works eccentrically, the lower ribs rotate internally, and the abdominal wall works concentrically, leading to a decrease in IAP.

Under pathological conditions, the diaphragm does not flatten adequately, expanding the lower part of the chest and staying in an oblique axis. After the first three months of life, the baby begins to raise their head against gravity when prone or raise their legs when in a supine position. At that moment, the diaphragm begins to work both as a respiratory muscle and as a stabilizing muscle. This is the period of life in which trunk stabilization occurs. In a physiological situation, the diaphragm descends and expands the lower part of the ribs. However, with dysfunction, the diaphragm does not descend adequately during postural activities, reversing the direction of muscle activity and pulling it toward the centrum tendineum. Clinically, this results in the "Hourglass Syndrome." (Figure 2)

Figure 2: The Hourglass Syndrome and its diaphragm dysfunction

Figure 1 above shows the diaphragm's insufficient flattening due to its concentric rigidity. This rigidity prevents it from descending towards the centrum tendineum tendon, leading to stiffness in the lower ribs area and disproportionate activation of the abdominal wall towards the umbilicus. As a result, the navel moves upwards, creating a horizontal abdominal crease and a possible protrusion of the belly below the navel, leading to the hourglass shape.

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Hope you had a nice read! see you soon to read about specific exercises to improve your breathing pattern!