PT on the Net Research

Assessing the Fundamentals - The Thoracic Connection, Part 1


Whether you are part of the health care or fitness industries, it is hard to deny the overwhelming reality of the health care crisis facing the United States. Just consider some of these startling statistics:

As the population ages and becomes more sedentary, and as orthopedic injuries rise in both severity and frequency, people are looking for alternative solutions as evidenced by the nearly $50 billion Americans spend annually on alternative medicine such as chiropractic care, acupuncture, and supplements. However, with the increased opportunity to work with de-conditioned participants, individuals with chronic injuries, and the clients with special orthopedic considerations, there has never been a greater time for the fitness professional to be both a leader and a solution to the health care crisis.

However, in order to be the solution that clients both need and want, there are some fundamental principles that fitness professionals must include in their programs. Unfortunately, the fitness profession seems to be moving away from these fundamental principles with the perpetuation of programs like “training regular joes like pros,” mixed martial arts and boot camp-type training, as well as kettlebells, cross over fitness and similar type training methodologies.

While clients present to the fitness professional with a multitude of issues, one region that requires particular attention is the trunk. The trunk — including the thoracic spine and rib cage — is one of the most over-looked regions of the body, and may just be the most important in correcting dysfunctional patterns and improving performing. This article will focus on helping the fitness professional understand the function of the trunk as well as its relationship to the pelvis. Additionally, it will look at common movement patterns and associated movement dysfunctions while outlining a corrective exercise progression focusing on:

  1. Addressing and improving the alignment of the thoracic as a driving cause of movement dysfunctions.
  2. Using corrective exercise patterns designed specifically to improve thoracic stabilization and limb function.
  3. Integrating movement progressions aimed at restoring function and improving performance regardless of the client’s goals.

Introduction

The thorax functions as a mobile adapter to allow the ranges of motion needed to perform sports as well as activities of daily living. It must be mobile enough to enable proper ribcage motion to support respiration and for the ranges of motion required for sport and activities of daily living. At the same time, the thorax must be stable enough to create a solid foundation for activities like lifting a child or generating high levels of intensity needed for certain sports (like hitting a baseball or striking a golf ball). This stability forms a base for lifting movements while serving as a relay station between the upper and lower extremities. Because several of the largest muscles in the body (abdominals and erector spinae) have significant attachments to the thorax, it provides the trunk the dual ability to be both stable yet generate incredible rotary power.

Although the thorax may appear to be relatively immobile, its unique design allows for a dynamic expression of mobility. The thorax is comprised of 12 thoracic vertebrae and 12 pairs of ribs. The 12 pairs of ribs articulate with the thoracic vertebrae (posterior) and the sternum (anterior). The last 2 pairs of ribs are considered floating, as they are not attached to the sternum. The thoracic spine alone contains 96 joint articulations: 24 vertebral, 48 facet, and 24 costal articulations. The lumbar spine by comparison has only 20 joint articulations. This suggests that the thorax is uniquely designed for significant degrees of mobility while the lumbar spine is better designed for stability.

The Thoracopelvic Canister

A canister is comprised of a lid, a floor, and circumferential walls, making it a very stable structure even under pressure. The thoracopelvic region of the body is similarly designed. The thorax, lumbar spine, and pelvis form the bony architecture while the intrinsic musculature including the diaphragm, pelvic floor, transversus abdominis, psoas, and quadratus lumborum, respectively, form the lid, floor, and walls. Achieving ideal alignment of the thoracopelvic canister is key to establishing proper function of the trunk and ultimately the extremities. Proper alignment of the thoracopelvic canister (TPC) occurs when the thorax is aligned vertically over the pelvis. The muscles surrounding the bony framework of the canister maintain optimal alignment and stabilize the thorax over the pelvis and the pelvis under the thorax.

As noted, the diaphragm, transversus abdominis, psoas major and minor, quadratus lumborum, and pelvic floor are key to providing intrinsic control of the thoracopelvic canister. This is not to suggest that the other muscles are not important to stabilization and movement of the TPC. Rather, it suggests that dysfunction in any one of these intrinsic muscles will drive compensatory changes in the global trunk musculature of the TPC including, but not limited to, the rectus abdominis, oblique abdominals, and spinal erectors. These compensations are commonly expressed in the postural, breathing, and movement dysfunctions that occur secondary to injury, surgery, and through learned behaviors.

Dysfunction of the Thoracic Region

Why is range of motion – particularly rotation – decreased in the thorax? There are 3 primary causes.

  1. Lack of proper central nervous system development. Physical medicine doctor Vojta reported that 1/3 of children never develop optimal central nervous system function. This often manifests in poor patterning and many of the postural/movement dysfunctions seen in the adolescent and adult populations.
  2. Trauma including surgeries, injuries (chronic and acute), and emotions. These factors effect how an individual is able to stabilize their trunk. Generally speaking, trauma creates a reflexive stiffening of the thorax and spine.
  3. Learned behaviors. These include everything from lifestyle (occupation, sports, and exercise choices) to adapted postures, and movement habits learned as early as childhood. For example: Many of the exercises people perform function in direct opposition to development as children. Consider the image below - the child’s spine is stable as the arms move around the stable trunk.

Notice how the developing child moves his spine around stable extremities (right hip and left shoulder). This develops simultaneous limb stability (right side hip and left side shoulder) and spinal mobility. The majority of the exercises performed by clients are in direct opposition to this function – they cause movement of the extremities around a fixated spine.

For example:

What about exercise cues that the fitness professionals commonly use when instructing their clients? Generally, cues such as “tighten your core,” “squeeze your glutes,” or “pull your shoulder blades down and back” are given to get the intended response of increased activation of the abdominal wall, glutes, and scapular retractors, respectively. However, the biggest problem for clients is not in activating prime movers, but activating the stabilizers, as well as coordinating the timing and efficiency of the muscles. The results of these exercise cues are increased problems such as compression syndromes at the spine and hips as well as stabilization issues of the scapulothoracic region.

It is important to note that this is not to suggest that these exercises are necessarily bad, but rather point out that they can have long-term results on the mobility of the thorax. Research on individuals with low back pain has shown that these individuals have a problem relaxing or turning muscles off. This is a similar pattern seen with many of the common movement dysfunctions of the thorax – the inability of clients to relax the muscles of the thorax. Performing bilateral patterns, as well as high threshold type training, perpetuate this up-regulation of the thoracic musculature adding to thoracic rigidity.

What are the long-term consequences of these strategies? Ultimately, these strategies lead to stiffness and rigidity of the thoracic spine and ribcage which in turn leads to:

Additionally, contrary to popular beliefs such as congenital and hereditary causes, movement and stabilization is influenced by learned behavior. Young children watch and adopt the postures, mannerisms, and movement patterns of parents, peers, and social influences. For example, models that are taught to hang off their hips and overly extend through their thoracolumbar junction influence the movements and behaviors of many young girls who then adopt these patterns. Additionally, there is a strong influence on the movement system by the fashion industry, especially the shoe industry. Because of the reflexive patterns on the thorax from the foot, as well as the compensatory foot mechanics from wearing high-heeled shoes, overly supportive athletic shoes, and the misuse of orthotics, each has the ability to dramatically affect an individual’s stabilization and movement patterns.

While the medical field is quick to blame genetics and old age, the resulting poor stabilization and movement patterns that result from improper neurological development, trauma, and learned behavior are the most common reasons for the majority of our client’s degenerative conditions, chronic pain, and decreases in overall performance. It is important for the fitness professional to recognize these causes as the solution will come in the form of returning to the fundamentals of human function.

Fundamentals of Improving Thoracic Function

Improving human function and therefore function of the thorax consists of several key concepts:

  1. Centration - improving alignment: the rib cage must be optimally positioned over the pelvis to improve both respiratory function as well as trunk stabilization.
  2. Respiration, stabilization, and thoracic dissociation: the thorax needs mobility to fulfill its respiratory function. Restoring respiratory function is key to beginning the process of functional improvement.
  3. Integration: the limbs will be used to drive thoracic rotation as seen in the developing child and in the adult gait pattern.

Centration

Centration is the ability to maintain an optimal axis of rotation throughout a movement pattern. The key to improving thoracic function is to achieve and maintain joint centration. The functional model illustrates that there are certain regions of the kinetic chain that are better suited for stability (foot, knee, lumbopelvic, scapulothoracic, cervical spine) while others are better suited for movement (ankle, hip, thoracic spine, glenohumeral, suboccipital). Once stabilization is achieved and dissociation occurs at the proper segments, integration of these regions is incorporated into functional movement patterns.

Stabilization & Dissociation

Stabilization is the ability to maintain optimal joint control in both static and dynamic movements. Stabilization is not merely contracting an area as hard as possible. The regions requiring most stabilization include the foot, knee, lumbar spine, pelvis, scapulothoracic and cervical spine).

Dissociation is the ability to move a segment or segments independent of adjoining segments. Dissociation is required most at the ankle, hip, thoracic spine, glenohumeral, and suboccipital articulation.

Integration

Integration is the ability to coordinate respiration, stabilization at the appropriate areas with dissociation of appropriate regions and coordinate these areas into functional movement patterns.

For example, during cable alternating pushing patterns, the individual stabilizes his TPC, dissociates through his left hip, and fixates the left side of his trunk as he drives thoracic rotation through his right arm press.

Improving function of the thorax must include improving stabilization of the TPC. Without adequate stabilization, the central nervous system will compensate and develop poor or inefficient movement patterns. This 3-step approach to TPC includes:

  1. Alignment
  2. Breathing
  3. Coordination

Optimal alignment of the TPC is where the thorax is aligned directly over the pelvis. This alignment is developed as an infant and occurs, in part, when the child reaches towards her feet. This pattern also develops the abdominal strength and intra-abdominal pressure that will be required for rolling and will eventually be used in the quadruped position. The goal of developing optimal alignment of the thorax and pelvis is to align the diaphragm with pelvic floor.

The diaphragm and pelvic floor (horizontal lines) should be aligned parallel to each other. What is the purpose of aligning the diaphragm with the pelvic floor? Proper alignment of the diaphragm and pelvic floor allows for optimal generation of intra-abdominal pressure (IAP). IAP is an important strategy for stabilizing the spine. It is one of the best strategies for decreasing compressive forces on the spine. As the diaphragm contract, it pushes the abdominal viscera inferiorly towards the pelvic floor. This increased pressure causes a reflexive contraction of the pelvic floor muscles. Pressure builds in the abdominal cavity causing stiffness and elongation of the spine effectively stabilizing the entire thorax. This explains why an individual will hold his/her breath (Valsalva’s maneuver) prior to moving a heavy load.

Why the focus on improving diaphragmatic breathing?

"If breathing is not normalized-no other movement pattern can be."
~ Karel Lewit

Breathing is essential to both the oxygenation as well as the stabilization of the entire neuromusculoskeletal system. In the absence of proper diaphragmatic respiration, there is loss of efficiency and increased compensatory patterns. As Lewit stated, in the presence of poor respiratory patterns, every movement becomes altered and inefficient. And the greatest challenge for the majority of clients is being able to coordinate respiration with core activation. Improving function begins by coordinating respiration with core activation as it is this ability that will ultimately determine your client’s success or failure in functional movement.

In part II of Assessing the Fundamentals, a corrective exercise strategy for improving function of the thorax, including functional progressions, will be addressed.

References

  1. Hodges, Paul, Richardson Carolyn, Hides, Julie. 2004. Therapeutic Exercise for Lumbopelvic Stabilization. 2nd Ed. St. Louis MO: Churchill Livingston.
  2. Liebenson, Craig. 2007. Rehabilitation of the Spine. 2nd Ed. Philadelphia, PA: Lippincott Williams & Wilkins.
  3. Lubeck, Deborah. 2003. The Costs of Musculoskeletal Disease: Health
  4. Needs Assessment and Health Economics . Best Practice & Research Clinical Rheumatology: Vol. 17, No. 3, pp. 529 – 539. www.elsevier.com.
  5. Michaud, Thomas. 1997. Foot Orthosis . Newton, MA: self-published.
  6. Osar, Evan. 2008. Complete Rotary Conditioning . Chicago, IL: self-published.
  7. Osar, Evan. 2010. Complete Trunk Conditioning . Chicago, IL: self-published.
  8. Pavel, Kolar. 2009. Exercise and the Athlete: Reflexive, Rudimentary, and Fundamental Strategies. Chicago, IL: course manual.
  9. Sahrmann, Shirley. 2002. Diagnosis and Treatment of Movement Impairment Syndromes. St. Louis, MO: Mosby.
  10. Szabo, Liz. Americans spend $34 billion a year on alternative medicine. http://www.usatoday.com/news/health/2009-07-30-alternative-medicine_N.htm ; dowloaded January 15, 2010.