Difficult to palpate, a challenging area to master as a manual therapist and dreaded by everyone getting worked on because of the horrible pain associated with it – in some ways “the psoas” is approached like the holy grail of the body: finding it can feel like a “quest” and while few are rewarded for their efforts many seem willing to die trying.
If you’ve jumped on the psoas-is-the-root-of-all-pain bandwagon, I have a few questions for you: if you’ve gone after the psoas attempting to release it – on your own, with a massage therapist, physical therapist or other method – are you better? Are you out of pain? If you’ve spent a lot of time trying to “release” this muscle, shouldn’t it be “loose” by now?
There’s been a LOT of hype about the psoas the last decade (or more). Is the hype justified? Is it really the most important muscle in the body and the biggest contributor to all of our pain?
I’ve instinctively felt for years that all this psoas hype is misplaced. I finally feel prepared to present my counter argument.
I’ve come to believe the iliopsoas are the most adaptive muscles in the human body, and our insurance policy against pelvic instability. This might make the iliopsoas two of the most important muscles in the body; however…in this scenario, if we are in pain then these muscles ARE LIKELY NOT THE PROBLEM, and if they appear “tight” they’re trying to HELP US. We’ve (unknowingly) taken out our insurance policy. Bolstering, blaming or otherwise focusing on the insurance policy that’s quickly running out because we haven’t fixed the root issue does nothing to heal the system that originally failed. If we heal the root issue our insurance policy can once again resume it’s role as critical back-up in case of system failure.
These are my theories and findings after 8 years in private practice and careful consideration of the science, anatomy, client stories and inner reasoning regarding this famous muscle group. I’m open to being wrong. I’m committed to keeping an open mind and learning alongside you, so please chime in with your thoughts.
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Important distinctions: psoas major and iliacus are often lumped together (because they function synergistically) and are called the iliopsoas; psoas major and minor make up the psoas group; most of the hype talks about the psoas but either neglects iliacus, OR they use the word psoas when they really mean iliopsoas.
I’ll attempt to stick to these distinctions in this article.
The iliopsoas flexes the femur at the hip joint (think of a hanging leg lift), and raises or flexes the trunk toward the hips from a supine or laying down face up position (think of a sit-up). They also laterally rotate the thigh at the hip, and psoas major laterally flexes the spine (side bending).
Psoas major also acts as a “shelf” for our organs to sit on, providing a barrier between those sensitive organs and nerves and our spine.
Most muscles have a primary function (action or movement). For example, your biceps flex your forearm while your triceps extend it.
Consider that all of the functions or actions of the iliopsoas can be performed by muscles that are bigger and usually stronger:
The primary actions of the iliopsoas are without a doubt hip and trunk flexion (in my opinion, and apparently the opinion of the internet). Yet I believe we rarely use the iliopsoas as the primary movers of these actions, relying instead on other muscles like the quad hip flexors and rectus abdominus, while the iliopsoas provide ancillary support and/or exist as our back-up muscles in case the primary movers fail to perform or become dysfunctional.
Many muscles, while responsible for a primary movement, also perform more than one action. The human body, after all, is a fully connected system that works as a whole to support movement.
Isolating ANY muscle group isn’t wise, because NO muscle functions in a vacuum and ALL muscles require the participation of the whole body.
I propose that isolating the iliopsoas or psoas muscle(s) specifically and attempting to “treat” them in isolation is especially dangerous, because of ALL muscles in the body these are the most adaptable, the most willing to change based on our habits, posture, sports, lifestyle…and this is a very good thing! That’s their job!
It’s my position that the primary role of the iliopsoas is as an ADAPTIVE MUSCLE GROUP that, by being highly adaptable, supports the primary functions of many large and small muscles.
Because they are SO adaptable, they can step in (if the brain asks them to) to stabilize the pelvis if necessary.
I believe the iliopsoas is our body’s insurance policy against pelvic instability.
They are likely NEVER the cause of pelvic instability, and “releasing” them may destabilize our spine or pelvis making us more prone to injury, pain or instability.
If we are to help the iliopsoas do its job, then we would do best looking at the surrounding muscle groups and see who is overworking, who us under-working, who is inhibited and/or fascially restricted. Taking care of all of this IS taking care of the iliopsoas.
If the psoas presents as “tight” it would, in my opinion, suggest a pelvic instability issue and/or low back pain pattern, and it is attempting to create stability, or in other words…we’ve cashed in on our insurance policy.
I’ve used quotations around “tight” because I believe this is one of several situations when the brain steps in and creates a neuroligcal tightening of a muscle to protect us from injury and spinal damage. The muscle is NOT in actuality tight or shortened, and if the pelvic instability or low back pain pattern is resolved, I believe it would relax into its normal healthy state.
If the psoas muscle itself is actually literally in a “shortened” state (rare in my opinion) it could contribute to “flat back” posture, or a posterior pelvic tilt.
Most people in modern society have the opposite: an anterior pelvic tilt (lordosis, or sway back), which would actually put the psoas into an overstretched position.
I’ve seen the iliopsoas blamed for both “sway back” and “flat back” postures, and I’ve seen both blamed on tight and weak psoas muscles. I don’t think it’s productive to examine these in detail because we’d be here all day since there are so many possible patterns for both of these scenarios.
As you can see…there is a lot of overlap and confusion as to what causes what regarding the iliopsoas, and I believe it’s because the iliopsoas doesn’t have a primary function and is so adaptable.
The psoas and iliacus are not in fact “tight” much of the time (at least not in my office), though they may appear so on occasion. More accurately, I don’t believe there are a lot of fascial restriction within the muscles themselves.
A “tight” muscle does NOT necessarily equal a strong muscle; a strong muscle does NOT automatically mean that muscle is “tight.”
Healthy muscles will be strong AND flexible.
I believe in most people the iliacus and psoas are weak.
If you have fascial restrictions within your abdominal cavity, fascial restrictions in your quad hip flexors, fascial restrictions in one or more of your high adductors, a “tight” quadratus lumborum muscle (due to a low back pain pattern, whether pain is present or not), or a restricted diaphragm (do you hold your breath a lot?) then chances are your psoas will appear tight due to being pulled on, especially if pulled in more than one direction at a time.
Releasing the iliopsoas may temporarily bring relief to an issue but this rarely (in my experience) resolves it for good (because it’s NOT the root of most problems), and it could make the pain worse. For example, if the iliopsoas has tightened up (neurologically) to protect the pelvis and/or spine from instability and it’s released, then we’ve created a scenario in which injury and damage is now much more likely.
If you attempt to go after psoas major specifically, I believe there is very real danger in irritating your organs, nerves, arteries/veins etc, so I NEVER recommend trying to dig into your belly to get at the psoas. You’d be far better off addressing your abdominal fascia specifically.
This abdominal fascia can get tight, knotted up and twisted due to processing stress or anxiety in the gut, sucking in the belly all day in order to have a socially acceptable “flat” tummy, digestive issues etc.
The MAIN area of the body that is likely pulling on the psoas causing it to appear “tight” is the quad hip flexor fascia.
I’m not sure why so many articles have been written on the psoas being the main muscle to suffer due to us sitting all day, when it seems obvious to me that it is our quad hip flexors (and specifically the fascia in this area) that take the brunt of all this sitting and become restricted, knotted up and “tight.”
Not only are we overworking our quads (specifically the quad hip flexors) by sitting all day, but we’re also an intensely quad dominant society. Almost all of our sports are quad dominant – soccer, football, gymnastics, cycling, running (this one shouldn’t be, but it often is, especially in trail running because many of us haven’t learned to use our hamstrings and glutes), swimming, Olympic lifting and certainly the biggest modern culprit: CrossFit (and Olympic lifting).
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