Lower Back Pain and the Diaphragm
Lower back pain is a very complex topic. We’ve posted many blogs on our site regarding back pain and the various subcategories that are related to it. The cause of lower back pain, the natural course of it, treatment options, prognosis, and prevention, are all examples of different areas for discussion. Spinal stability is just one of these aspects of lower back pain and is the topic of this blog.
The term stability as it pertains to lower back pain can be interpreted in various ways depending on who is reading it. For example, a spinal surgeon would think of instability differently from a chiropractor or a physiotherapist. When we speak of stability in the spine, we are typically referring to its ability to hold a position. Spinal stability is in large part dictated by the geometry and shape of our joints as well as muscular activity in the area. In the realm of the rehabilitation profession, the focus is usually how the muscles interact with the spine to create stability. For example, it has been well established that people with chronic lower back pain show an impaired function with respect to the orchestra of muscular activity that supports the spine during various movements. Perhaps one area that is overlooked in this area of back pain treatment is how breathing relates to the muscular activity around the spine.
The Role of Breathing
Sometimes we discuss the lumbar area as a “cylinder.” This means that the spine sits in the middle of the cylinder and the muscles and viscera around the spine create a cylinder shape. When we breathe in and breathe out and when we “bear down” the pressure and geometry of this cylinder changes. This affects the stability of the spine. The top of this cylinder is a muscle called the diaphragm. The diaphragm is perhaps the primary muscle for breathing, but it also plays a role in spinal stability and intra-abdominal pressure. Logically, since the diaphragm plays a role in spinal stability and in breathing, breathing is linked to spinal stability!
Pain and injury can affect the way our muscles activate through a complex mechanism in our nervous system. In a non-injured state, a person should be able to contract all the abdominal and lumbar spine muscles at a low level to stabilize the spine while maintaining proper respiration and speech. For some people, these things all have to occur separately. They hold their breath to stabilize the spine or they breathe freely with an uncoordinated pattern that doesn’t include a deep breath or any spinal stabilization. An interesting study published in the European Spine Journal investigated the breathing patterns of people with and without lower back pain. They had the subjects standing and lying down and had them perform three different motor tasks. What was interesting is that they found those patients with chronic lower back pain had a greater chance of having altered breathing patterns. This was independent of how severe the pain was. This altered breathing relates to altered neuromuscular control during simple tasks. In other words, patients with chronic lower back pain had a reduced ability to support their spine using their muscles. In particular, these people have a reduced ability to use the diaphragm properly resulting in pain in the diaphragm and back.
Part of the Orchestra
Unfortunately, practitioners often fall into a habit of over-emphasizing the importance of individual muscles and how they contribute to stabilizing the spine. I’ve posted several blog entries on this topic. When I started my career, it seemed like everyone was talking about the multifidus as if it was this “hidden secret” that was now discovered. It seemed at that time, practitioners were advocating proper training of the multifidus only, since it was the key to solving lower back pain. Not true! I would urge those reading this blog to not fall into the trap of over-emphasizing the importance of the diaphragm and how it relates to spinal stability. There is not one muscle that is more important than any other. As often read in the literature, the muscular activity around the “core” area is best thought of as an orchestra. They all have their role and their time to be involved in the intricate task of supporting our lumbar spine. There isn’t one instrument that is the most important in an orchestra. This study as described above provides some valuable insight into the role of the diaphragm, how it contributes to spinal stability and how breathing, therefore, relates to lower back health.
Proper breathing is important for our various body functions that require oxygen. It’s also been discussed with respect to stress, the mind-body connection, and relaxation. We now know that it also relates to spinal health and spinal stability. Rehabilitation professionals would be wise to incorporate this into their treatment of lower back pain, assisting patients in identifying faulty breathing patterns and offering strategies to promote better habits. In a nutshell, the emphasis should be on elevating and expanding the ribcage during inspiration while being aware of spinal biomechanics and movement patterns. The diaphragm is indeed part of the orchestra!
Roussel N et al. Altered breathing patterns in chronic low back pain patients. European Spine Journal 2009; 16: 1066-1020.