Illustrations by Andrew MannieOriginally published in Massage Bodywork magazine, June/July 2001.
Copyright 2003. Associated Bodywork and Massage Professionals. All rights reserved.
This is the third in a series of articles about the actions of the psoas and the complex of muscles around it. In the first round, we thought about whether the psoas is a medial or a lateral rotator of the femur (it isn't). In the second, we considered whether the psoas was a lumbar flexor, or extensor (it is). This time, we turn to the question of what can happen if the psoas is shorter on one side than the other. Once again, we must give you fair warning that the ideas put forward in this series are speculative, and designed to encourage your thinking and experimentation. They are not necessarily scientifically confirmed or agreed on by all workers in the field. The final word is not in on these issues, so take the following with a grain of salt.
An idea put forward by a number of people is that unilateral psoas imbalance is an active participant (and in some cases the cause) of some thoracico-lumbar spinal rotations. We want to tease out a few distinctions for this generalized statement, examine the process by which it might happen, and then point to some treatment options implicated by the arguments.
FIG. 2: At the thoracico-lumbar junction (T12), there is a sudden and important change in orientation of the spinal facet joints from sagittal below to coronal above.
The first thing we need to note is there are a number of types of spinal rotation. At its worst, postural spinal rotation is termed scoliosis, but there are a number of rotational patterns that are less severe. In fact, in my own practice I have yet to see anyone in 25 years who does not have at least some minor form of mid-spinal rotation. It is a commonplace pattern, but not all these patterns qualify as a scoliosis. The milder forms are functional (scoliotic behavior), not really structural (i.e., where there have been changes to the shape of the facets or ankylosing of the joints). True idiopathic scoliosis is a difficult and complex pattern that can require medical intervention. It is the milder form of functional spinal rotations that are more amenable to being eased and lengthened through manipulation, and it is those milder rotations which are under discussion here.1
In examining these functional rotations, we need to know a little bit about the spine first. Each spinal vertebra has three joints with each of its adjoining vertebra: the cartilaginous joint of the disc which joins the vertebral bodies in the front, and two small synovial facet joints from the neural arch in the back -- the ones that pop when you stretch or adjust your back. The discs allow all kinds of movement, since they are essentially tough water balloons separating the bodies. But the articular facets of the joints in back overlap each other like shingles, and therefore they tend to allow some movements and disallow others. The lumbar facets lie mostly in the sagittal plane, and therefore they allow flexion-extension and side-bending, but only a little bit of rotation. The thoracic facets lie mostly in the frontal plane, so they allow a good deal of rotation, but only a little flexion-extension.Psoas-Induced Rotation
At my school, to assess the primary thoracico-lumbar rotation, we use a little test called Breathing Down Their Neck. Have your client stand in their underwear; stand right behind them and look down their back -- breathing down their neck, as it were. If necessary, put your hands on their hips and "square" them to the client's feet. Because of the foreshortening involved in looking directly down the line of the back, whatever rotations they have will be very clear. You will see it in the track of the spinous processes and even more in the way the erector spinae muscles in the laminar groove either dip in or protrude back toward you. Although there may be a compensatory counter-curve in there, the primary rotation is usually easily visible this way. Practice this with the next 25 people who come into your practice and I guarantee you will be able to spot these rotations and curvatures with more facility.
The discussion that follows shows how the psoas may (and I believe it does) participate in these thoracico-lumbar rotational patterns. It is not particularly important to decide whether the psoas is the cause of the rotation, because even if the cause lies elsewhere, the psoas will have adapted to the rotation and will thus need to be addressed as part of the solution, whether it was the root source or not.
FIG. 3: The first stage of the rotation induced by a unilateral pull of the psoas is a simple lateral flexion to the side of the shortened muscle (redrawn from Netter).
Anatomist Frank Netter described a three-stage progression of psoas-induced (or accompanied) rotation, and Figures 3-5 are adapted from his drawings. Let us follow his logic and see where it gets us. The upper end of the psoas attaches to the transverse processes of the lumbar vertebrae and to the sides of the lumbar vertebral bodies near the discs. (In fact, I would submit that the ultimate attachments of the psoas are to the annulus of the discs.) And the lower attachment of the psoas (for the purpose of thinking about its effect on the spine) is where it crosses the iliopectineal ridge above and in front of the hip joint. In other words, the pull of the psoas on the spine, as we noted last issue, is down and forward.A Natural Bend
If we imagine shortening one side of the psoas, the downward pull would naturally start to bend the lumbar spine toward the tightness so we would get a lateral bend of the torso toward the shortened muscle, as shown in Fig. 3. Therefore, Stage 1 of this psoas-induced rotational pattern is a side-bend which is concave on the side of the short psoas.
Since the line of pull of the psoas is also forward as well as down, the psoas would also act on the spine to pull the transverse processes and the sides of the lumbar bodies forward on the side of the shortness. As you can see from Fig. 4, this turns the lumbars away from the shortened psoas. But because of the plane of the lumbar facets we looked at earlier, the lumbars have a limited ability to rotate -- maybe 5 degrees total. The rotational force is transmitted up to the thoracics, and then to the rib cage. Stage 2 of this sequence is that the lumbars, and frequently the rib cage and sternum also, turn away from the shortened psoas.
FIG. 4: The second stage is characterized by a rotation of the spine and rib cage away from the tight psoas (redrawn from Netter).
In these cases, we have a lean toward the shortened side and a turn away from it. If this were the end of the story, it would be a lot easier than it actually is to assess these patterns. But Stage 3 makes it more confusing (Fig. 5). Stage 3 is not orchestrated by the psoas, but by the person's compensations for the psoas shortening. The person beset by Stage 1 and Stage 2 of this pattern has her pelvis going in one direction and her chest headed in another. Consciously or unconsciously (most often the latter), the person will turn some part of the body back in a counter-rotation against the pattern created by Stage 1 and 2. This has the desired effect for the person of making them look better in the mirror, and effectively gets their sternum and chin going in the same direction as their knees, which is certainly an advantage in walking. The problem for the person is that one twist has been compounded by another twist -- and both of them act to limit movement and to shorten and compress the body. This causes lots of muscle tension, obviously, and deposition of extra fascia, but can also lead to awkward movement, and ultimately to more severe restrictions and pain.
The problem in assessment comes when we realize how many different patterns of compensation can be used to create Stage 3. The pattern shown in Fig. 5 is an often-seen compensation, where the rib cage is turned counter to the thoracico-lumbar rotation to forcibly bring the sternum back in line (more or less) with the pubic symphysis. This is indeed a common pattern of response, and it is performed, generally, by some part of the abdominal obliques -- in other words, by muscles more superficial than the psoas.
Notice what is happening when this is the case: the core muscles are trying to take the spine in one direction and the outer muscles of the belly are trying to take it in another. Even if the person looks perfectly balanced (which they won't, if we really look at the details), they still have a lot of counter-balancing muscle tension going on, like having the accelerator and the brake on at the same time. And the practitioner who releases the abdominals may be in for a surprise: when the client stands up, you may discover they are more twisted than when they lay down. This can be a disconcerting experience -- "I thought I was making them better by releasing their tension."
This is the perfect time to remember an old joke: You know the difference between an amateur and a professional? The amateur says "Ooops," while the professional says, "There." Here's one of those situations that separate the amateur from the professional. If you spent part of your session releasing the abdominals and your client stands up with noticeably more twist, did you cause the twist with badly balanced work ("ooops"), or simply take the surface compensation off a spinal rotation to expose the core pattern ("there")?
FIG. 5: The third stage involves the person using other muscles to bring the rib cage back the opposite way, making diagnosis and treatment tricky (redrawn from Netter).
There are a few clues. The first is implied in Stage 3 (Fig. 5), while the second requires your close and intuitive observation. If we look at Fig. 5 closely, we can see that one side of the rib cage is closer to the hip bone than the other. If we look at Stage 1 (Fig. 3), we see the same thing, but on the opposite side. Still, there is another difference. Look closely and you will see that the rib cage is offset a bit to the first side (the client's right, in this case). When you see this side shift of the rib cage relative to the pelvis, you can bet you are looking at a rotational pattern, and you can suspect it is going to look worse before it looks better.
The other way of measuring whether you are doing good or harm is more subtle: Are they taller after your session than they were before? The process of going into these twists -- the original twist and the counterbalancing twist -- shortens the body. The process of coming out is a process of lengthening. Therefore, if you do a session and the person stands up twisted, you must then look to see whether they are more lengthened through the spine than they were when you started. If they are more compacted, then you are correct in saying "Ooops." If they are longer, you are justified in saying "There," and you can go on to work on the core rotation via the psoas and the deep spinal musculature.
It is not always so, however, that the client twists the entire rib cage back in Stage 3. Although it is a common response, I have seen several variations on the theme. In some, the bottom of the rib cage follows the lumbars, and the top of the rib cage is turned back, creating a twist through the ribs themselves. In others, the rib cage as a whole follows the lumbars, but the shoulders are twisted back to counterbalance so that the shoulders and ribs are going in opposite ways. In still others, the neck does the entire job of compensation.
While all these patterns can be confusing, a sharp eye (and some training in body reading) will help you discern what's what. And there's a summary statement, which works pretty well: the umbilicus points away from the short psoas. Abdominal surgery, strange fat patterns, and sheer cussedness may create exceptions to this rule, but it is worth a try in most cases.
Once you have determined, either visually or via palpation, which psoas you need to work with, there are a number of ways to work with it -- supine, prone, side-lying and sitting -- to restore fascial and muscular length. The psoas may need to be freed from surrounding tissues, especially the iliac fascia. It may need to be worked in eccentric contraction (similar to a "pin and stretch" technique), or in concentric contraction. Having the client turn their ribs away from their rotational pattern may help while you are working.
Because hand placement is so crucial in the execution of these techniques, and the psoas area is so full of other problematic possibilities -- like the mesenteric and large intestine attachments, iliac arteries, the ureters and the kidneys -- I choose not to describe those techniques in detail, and urge you to get to a training session where they are taught. But I hope this discussion of the possible role of the psoas in spinal rotations leads to useful new assessments and treatments for you.
The next issue will include the final article in this "psoas pseries," in which we will consider the muscles surrounding the psoas, and how they can mimic the actions (and restrictions) of the psoas itself.Thomas Myers, Certified Advanced Rolfer(R), LMT, NCTMB, studied directly with Drs. Ida Rolf and Moshe Feldenkrais, and has practiced integrative bodywork for more than 25 years in a variety of cultural and clinical settings. Myers directs Kinesis, Inc. which develops and runs training courses internationally for manual and movement therapists. He served as a founding member of the NCBTMB, and as chair of the Rolf Institute's Anatomy faculty. His articles have appeared in a number of magazines and journals, and a book is now underway on his "Anatomy Trains" Myofascial Meridians approach. Myers retains a strong interest in perinatal and developmental issues around movement. His practice in Boston combines structural integration, physiological rhythmic sensitivity and movement. He lives, writes and sails on the coast of Maine.References