by Robert “Skip” George, D.C., CCSP, CSCS, PRC
Faculty, Postural Restoration Institute
Rib flares have been a hot topic for discussion in fitness and rehabilitation with much debate on causes and consequences as to their functional, visual and aesthetic qualities in today’s movement specialty world. The purpose of this article is to define some of the underlying causes of rib flares, notice any differences left to right side and provide some specific approaches to management of an asymmetrical airflow pattern that contributes to their prominence.
The big picture is that all of us are asymmetrical and always will be! For starters, our hemi-diaphragms are different on each side and biased with the right being more responsible for respiration and the left having more of a spinal stability role. The right diaphragm sits on top of the liver which helps to provide it’s domed shape, has a bigger central tendon, stronger more plentiful crura attachments to the lumbar spine and is better positioned for breathing. The left side of the hemi-diaphragm sits under the center left positioned heart and has a more flat, descended and tonic presentation with a smaller central tendon and fewer crura attachments to the lumbar spine. Both sides of the diaphragm attach to the sternum and ribcage as well as either side of the lumbar spine with the right crura descending 1 ½ to 2 lumbar vertebrae lower than the left. Oh, and one last thing, we have two lobes of lung on the left and three lobes on the right.
Every system in our bodies is asymmetrical anatomically including neurology, vascular, digestive, visual and hearing. For this topic, management of airflow has a direct influence on the position of the entire ribcage left to right side and front to back.
So, what does this have to do with rib flares? Let’s look at what moves ribs in the first place. There are three main forces on our ribcage. They include gravity, muscles that attached to the thorax and airflow pressure into the chest wall affecting its shape, form and function. Since breathing is such an important issue in performance and rehabilitation, recognizing the importance of airflow management in and out of a chest wall, especially exhalation, is critical.
The diaphragm is the primary source of inhalation as both central tendons descend creating negative pressure in the chest wall allowing the lungs to expand for perfusion of oxygen. The entire thorax expands and the ribcage, especially the lower ribs, will flare into what is defined as external rib rotation from an internally rotated starting place ideally. This inhalation pressure, or airflow sense, inhibits or relaxes the intercostals and other muscles of exhalation as the external obliques engage for lower ribcage expansion or external rotation of the lower ribs. It is the excess external rotation of the lower ribcage that does not return to an internally rotated or positioned state that creates the presentation of flare.
As mentioned before, exhalation may be the most significant part of this discussion as it relates to rib flares. Muscles of exhalation include the intercostals as well as a muscle inside the chest wall called the triangularis sterni. If you reference Grant’s Anatomy, you will see there is a difference left to right side of this muscle of exhalation that further demonstrates asymmetries especially as it relates to management of airflow out of a ribcage.
Here’s where it gets interesting. Our internal obliques (IO’s)attach to our lower ribs from the pelvis as our transverse abdominis (TA’s) attach to the lower six ribs, diaphragm and thoraco-lumbar fascia. Together they are also primary muscles of exhalation as they draw the lower ribcage down, in and back as well as provide tri-planer movement to the ribcage and lumbar spine! Therefore, the IO’s and TA’s are critical in positioning of the lower ribcage as well as the other aforementioned muscles of exhalation.
Upon observation, which side of the thorax do you observe flares to be present? Is it different left to right side? When is a person lying on their back does their lower ribcage angle seem to be different left to right side? In addition, when a person is prone, or standing, does one side of the back of their ribcage seem to be more prominent left to right side? These are clues to the differences and management of airflow and position and posture of the ribcage and spine.
Typically, you may notice more rib flare on the left even if flare on the right is present. The source or reason behind this presentation is a more hyperinflated left anterior chest wall as compared to the right. Remember that the flatter, tonic and descended hemi-diaphragm on the left results in more internal air pressure or expansion of the left anterior chest wall and with it the lower ribcage. In addition, for most humans, their abdominal wall on the right is more dominate especially the IO’s and TA’s. This results in more compressive force on the right ribcage as opposed to the left which contributes to more internal airflow pressure into the left anterior chest wall via the right hemidiaphragm resulting in an increase of respiration driven rib flare on the left.
As you may have noticed, many people are unaware of their breathing. Dr. Karel Lewit once said that breathing is the most common movement dysfunction. Sitting at desks all day, looking at screens and phones and being sedentary are all contributors to a disconnection of body awareness especially breathing. Short shallow breathing is common starting with inhalation upon inhalation with no awareness of exhalation. This results in getting too much air in without expelling air and acts like a rachet driving an individual into a stuck place of hyperinflation. This feeds into accessory muscle overuse including back muscles to extend in an attempt to get more air into an already hyperinflated ribcage posture. They will use their neck muscles to try to pull air into their ribcage that results in accessory muscle overuse. No wonder people have increased lumbar lordosis, flat thoracic spines, forward head posture and yes, rib flares.
What will be helpful is to assess and provide a strategy to address asymmetries. These natural asymmetries provide patterns of respiration that directs position, posture and anatomical presentation of a rib cage. Coordination, activation or facilitation of abdominal wall muscles, starting with muscles of exhalation ( IO's and TA's), is critical especially on the left side of the thorax. This achieves a new position starting with the lower ribcage in relation to a properly positioned pelvis while learning a new sense of body awareness during breathing. This is known as abdominal wall opposition that maintains a more balanced shape of the thorax during inhalation after first achieving full, relaxed exhalation.
The most important issue of abdominal wall opposition is its direct influence of the shape and form of the diaphragm. During exhalation, the ribcage drapes around the diaphragm creating what is known as a Zone of Apposition (ZOA) or domed shape of the diaphragm. Once a ZOA is achieved, it not only affects diaphragm position and shape, but provides rotational performance as well! More on the ZOA in a future article.
Asymmetries are a gift for movement and performance. It is when we are not recognizing and managing those asymmetries that we rely on for performance, stability and rest that it becomes an issue. Learning to reposition, retrain and restore a more balanced position and posture starts with recognizing the specific asymmetries of airflow beginning with differences of the diaphragm left and right side and how airflow or pressure sense is delivered into both sides of the chest wall. How we manage airflow affects not only rib flare position but our entire axial skeleton. Rib flares are just one indicator of what could be occurring in the entire axial skeleton.
Attached are some strategies to begin to address not only rib flares but to balance the entire system in the context of being an asymmetrical human being. Notice the use of a balloon to provide more resistance for abdominal wall engagement. This provides for more facilitation of the intercostals, internal obliques, transverse abdominis and triangularis sterni for the purpose of drawing the lower ribs down, in and back thereby reducing rib flare while providing internal rib rotation.
Teaching our clients and athletes how to better sense their bodies, left and right side, is a science and art that has been emerging in the performance and rehabilitation world and is becoming critical in understanding structure and function. In future articles I will describe why asymmetries determine which leg we prefer to stand on, pelvic floor dysfunction and the Zone of Apposition for power and performance.
About Robert "Skip" George
Robert “Skip” George, D.C., CCSP, CSCS, PRC is a certified chiropractic sport physician. Over the years his practice approach expanded to integrate chiropractic, rehabilitation and sports performance training into a community-based wellness care model. He has certifications in rehabilitation, functional movement, strength and conditioning as well as a strong focus on respiration and the diaphragm and for performance, power and rehab.
Over the course of his career, he has treated and trained a wide variety of patients including grade school to college level athletes. He has also treated and provided performance training to professional athletes, elite military personal as well as aging weekend warriors that want to stay vital and continue to function at the highest level.
Dr. George was the first chiropractic physician to become a Postural Restoration Certified (PRC) practitioner by the Postural Restoration Institute (PRI) in 2014. He was then invited to become a faculty member for PRI in 2015. He currently teaches PRI course work nationally as well as internationally. Dr. George practiced in La Jolla, CA until 2021 when he moved to North Logan, Utah to continue private practice, mentor other health professionals and teach for PRI. He is an avid alpine and Nordic skier as well as a seasoned mountain backcountry enthusiast. In addition, his motivation to move to Utah was to pursue his passion for the outdoors and photography of nature and wildlife.