In investigating the conditions that can beset the sacro-iliac (henceforth, S-I) joints, I have arrived at a number of findings that make sense of the condition and point precisely to what we can do to relieve S-I joint pain and attendant symptoms.
We will consider both one-sided and bi-lateral S-I joint pain.
SYMPTOMS OF S-I JOINT PAIN SYNDROME
- pain across the low back (both sides)
- pain just below the waistline (one side)
- pain deep in buttock(s)
- deep pelvic/abdominal pain (ache, “lightning”-like pain), sometimes with nausea
- numbness in front or side of thigh
- pain like a wire going down the spine into the pelvis
- a gripping sensation at the lower abdomen
- sciatica (if accompanied by other symptoms)
- groin pain
- testicular pain or burning bladder sensation
DIAGNOSES INDICATING THE THE S-I JOINTS SHOULD BE CHECKED FOR POSITION:
- Krohn’s Disease
- Irritable Bowel Syndrome
THE BASIC UNDERSTANDING
In brief, S-I joint pain arises from excessive muscular compression (tension) and twisting forces on the S-I joints originating both from below (legs) and from above (longitudinal muscles of the trunk) during walking. Those compression and twisting forces converge at the S-I joints, drawing the pelvic bones into a distorted stress pattern that places strain on S-I ligaments, causes pain, and triggers reflexive muscular contractions throughout the trunk and legs that themselves cause pain, as well as referred nerve pain and radiating pain (e.g., S-I joint-to-groin or to the inside surface of a hip bone/ilium). This complex array of symptoms, we may call, S-I Joint Syndrome.
The S-I ligaments are not the cause, but the victim of those forces and the pain usually locates, not at the jammed S-I joint, but at the other-side S-I joint.
To relieve S-I joint pain, we
- Cultivate/restore healthy, free, balanced patterns of movement and rest in the musculature.
- Return the resting tension levels of the involved muscles, which are habituated into a contracted, shortened state, back to complete rest/relaxation and complete resting length.
simultaneously. I will discuss how we do that, later.
Bi-lateral S-I joint pain simpler than one-sided SI joint pain. Bilateral S-I joint pain involves the compression and twisting forces named above (but not yet described). One-sided S-I joint pain combines compression and twisting forces with asymmetrical muscular pulls (pelvic rotation with elevation with one hip), caused by Trauma Reflex.
Everyone has experienced Trauma Reflex. Caused by pain, it’s a protective withdrawal response of the painful part away from the direction or cause of pain. Its other name is “cringing”.
Trauma Reflex (the cringing response triggered by injury) is almost always asymmetrical because any given injury generally occurs to one side.
Trauma Reflex is not a momentary muscular action like the stretch (myotatic) reflex, but one that lasts at least as long as the pain of injury persists — and commonly much longer — up to decades. When it lasts for decades, it’s that the injury has left such an impression on the brain that it displaces the healthy, familiar body image so that it’s as if the injury is always “happening right now” — along with the reflexive pulling away (muscular tightening). This change constitutes a change of muscle/movement memory.
Asymmetrical muscle pulls (and asymmmetrical posture) place more stress on one S-I joint than the other.
Though one might be tempted to regard S-I joint pain as a ligamentous problem, it is not; it is a neuromuscular problem that produces ligamentous strain as a by-product. I am emphatic about this point and will explain, shortly.
THE STRUCTURE, FUNCTION, AND LOCATION OF THE S-I JOINTS
The sacrum is the meeting point of tensional and compressional forces meeting from above and below, as noted earlier. The sacro-iliac (or ilio-sacral) joints are the less mobile of the joints involving the sacrum (meeting of sacrum and ilia or “wings” of the pelvis); the other joint is the lumbo-sacral junction (meeting of sacrum and lowest lumbar vertebra, “L5”).
In the healthy state, most of the sacral movement occurs at L5/S1; some movement occurs at the S-I joints. Said another way, because it is more tightly bound to the ilia than to L5, the sacrum is functionally “more part of the pelvis than it is part of the spinal column”.
In the unhealthy state, the sacrum becomes (functionally) “somewhat more part of the spinal column and somewhat less part of the pelvis” and compression and twisting forces at the S-I joints strain the ligamentous connection.
Compression forces at L5/S1 come from muscles of the trunk in contraction, primarily the paraspinal and psoas muscles, and the quadratus lumborum. Additional compression forces from the trunk come from the muscles of the abdominal wall (obliques, rectus abdominus), involved in the asymmetrical pulls of Trauma Reflex.
Pulling forces at the S-I joints, themselves, come from muscles that run the span between the legs and the pelvis — the psoas muscles, the hamstrings, hip joint flexors, buttocks, and femorii rectus (you like the Latin?) — and combine with the movements of walking and the weight-forces of sitting to affect the S-I joints.
It is here that we pause to re-set our way of looking at what I am describing. To this point, I have described the situation in anatomical terms — but anatomical terms are inadequate to understand what is going on with S-I joints; what is needed are functional terms — terms that describe sensations and movement: somatic responses. The cringe response (Trauma Reflex) is an example of a somatic response.
In the remainder of this piece, I will use both anatomical and somatic perspectives — anatomical terms so you can visually imagine what I am describing and somatic descriptions so you can imagine in yourself what that might feel like (assuming you have developed enough proprioceptive awareness to do that).
THE LIVING EXPERIENCE OF S-I JOINT PAIN
S-I Joint Dysfunction often starts with an injury, sometimes, an injury substantially in the past. The injury generally involves a hard blow that sends shock waves into the pelvis from a specific direction, shock waves sufficne to displace the sacrum from its centered position to an off-center (twisted) position. The brain senses the displacement and contracts the musculature within, above, and below the pelvis to prevent further displayment — muscular contraction sufficient to cause pain and postural distortions beyond those of the original injury and that may last indefinitely. Diagnosis: S-I Joint Syndrome.
A secondary cause may be habituated postural reflexes of stress that involve the back and/or front of the body. These reflexes, Landau Reaction and Startle Reflex, are discussed in the definitive article, Clinical Somatic Education: a New Discipline in the Field of Health Care, by Thomas Hanna
When the hamstrings tighten in Landau Reaction, they pull the legs back (into extension). Any movements of the legs forward, as in walking, then require additional muscular force from the hip joint flexors, psoas and femoris rectus muscles. Habituated Landau Reaction thus leads (by compensation) to tight hip joint flexors. This pattern of co-contraction makes the legs functionally “more part of the pelvis” — binds and jams the legs into the pelvis, making them less independently free to move. The legs feel heavy and walking slows, dragging the ilia along with them in opposite, twisting directions.
When we tighten in Startle Reflex, the reflexive movement is into collapse and curling up. People rarely curl up completely, but the musculature tightens in that pattern and posture changes accordingly into a partial crouch.
That crouch pattern involves the abdominal muscles and the hip joint flexors, including the psoas muscles. The movement is into retraction (pulling in) of the legs in preparation for collapse and curling up. The hamstrings and hip joint flexors actually tighten in readiness to pull the legs in and collapse and curl up.
Now, how does that affect the S-I joints?
As the legs move in opposite directions when walking, walking induces a moving twisting motion into the pelvis right at — you guessed it — the S-I joints. When legs are jammed into the pelvis, this way, each step of walking forces the ilia (location of the hip joint/acetabulum) to move with the legs somewhat more than in the healthy state. (In the healthy state, the ilia move in a complex, round motion with each step, but rather less than when the leg-pelvis muscles are tight — and within the tolerance of the S-I joints.)
Now, what happens to the ligaments of the S-I joints with this kind of excessive motion? They get strained.
And what happens to tissue that is chronically under strain? It gets inflamed. Inflammation is nature’s way of forcing fluids and nutrients into tissue that is strained (or injured) so it can heal.
THE VIEW FROM ABOVE
But wait! There’s more!
We just described the effect of “tension from below” (the legs). What about “tension from above” (the trunk)?
When tight trunk muscles bind the sacrum more tightly to the lumbar spine, the ordinary, round pelvic movements of walking are no longer as free of the lumbar spine. The lumbo-sacral junction is “stiffer”; the round movements of walking must be re-distributed: less at the lumbo-sacral junction (L5/S1) and more at the S-I joints.
So, the S-I joints get strained by movements both from below and from above. They get it from both ends.
How’d you like to be in the middle, mediating between two uptight parties intent upon taking action that affects YOU??
Now, the psoas muscles have a special part to play, here. They cross the span between “below” and “above”, connecting “below” with “above” (from the lesser trochanters of the legs, through the abdominal cavity, to the spinal column as high as the tendons (crura) of the diaphragm). When they’re tight, they “seal the deal” — jamming both what’s below and what’s above into the sacrum.
So, with each step of walking, the S-I joints take the brunt of movement.
That’s sufficient to account for bi-lateral S-I joint pain.
But wait! There’s more!
ONE-SIDED S-I JOINT PAIN
Back to Trauma Reflex.
It’s true that injuries usually occur to one side, isn’t it?
What happens with any injury, as we’ve noted, is Trauma Reflex — a tightening centered at the injured region and including all of the tensions involved in changing our movements to protect the injury.
An injury to one side triggers asymmetrical tightening that commonly shows up as a side-tilt (“C-curve” scoliosis) and a rotation (postural twist) — typically with one hip up and the same-side shoulder down and back. With the side tilt and twist, weight distribution goes off-center and the musculature must compensate (for balance — the essential meaning of the term “compensations”).
In the trunk, the muscles above induce compression forces more into one S-I joint than the other. Below, the hip joint muscles contract asymmetrically, left-to-right and in different ways on the two sides. (In the healthy state, those muscles do not contract in a “unitary”, all-or-nothing manner, but selectively, according to the position-in-movement of the legs.) In the unhealthy state, they stay contracted at all times in the asymmetrical pattern of injury-and-compensation, even in movement, and introduce drag, compression and strain into the situation.
These changes all constitute changes of muscle/movement memory.
And guess what that does to the sacrum.
If you can’t guess, I’ll tell you: it induces a twist — and rather forcefully and for a long time.
S-I joint strain?
CLARIFYING COMMON DESCRIPTIVE LANGUAGE
Now, I want to take a moment to address the term used to describe deviations of the sacrum from its healthy, centered equilibrium: “up-slip”.
There ain’t no “slip” to the up-slip. The sacrum doesn’t exist in an empty space like a laboratory skeleton and just kind of “slip” up — and the S-I joint isn’t slippery. The sacrum exists in a tensional/compressional equilibrium, and rather securely so, the meeting place of forces that change moment to moment and that affect its position. It doesn’t “slip”; it is rather forcefully pulled, compressed and twisted — and for a long time – it is drawn and “floats” into an altered position over time, in the midst of those tensional and compressional forces. It’s partially dislocated. Just some perspective. Rather than an “up-slip”, it’s more an “up-clunk”.
OK. Now we have not only a compressed S-I joint (from above and below) but also a torqued/twisted sacrum felt as pain below the waistline — maybe more on one side, maybe all the way across. Can you feel it?
What do we do, now?
Well, for one thing, we see that ongoing forces are inducing S-I joint strain and that those forces are coming from habituated neuromuscular reflexes — meaning coming from and governed by the nervous system.
We also see that the strain on ligaments is not the fault of the ligaments, but of the nervous system.
That means that we can’t correct the problem in any lasting way by addressing the ligaments (and to stretch or loosen the ligaments may reduce their strain, but it also de-stabilizes the joints they hold secure). It also means that we can’t massage away the problem (have you noticed?). It means that we have to free the person from the grip of Landau Reaction, Startle Reflex, and Trauma Reflex (the brain reaction to the shock of injury and to distorted pelvic stresses) and establish free, balanced, and well-coordinated movement that gives back to the sacrum, S-I joints, and lumbo-sacral junction (L5/S1) their healthy, centered, free movement at balance.
Have I said it?
But here’s the question: how??
THE PANDICULAR RESPONSE — THE “WHOLE-BODY YAWN”
There exists a neuromuscular response, an action pattern, ideally suited for retraining postural reflexes and movement — the pandicular response. Applied methodically to contraction patterns via controlled and regulated movement patterns, the pandicular response frees a person from involuntary muscular tensions, such as those that cause S-I joint pain.
The pandicular response works more in the spirit of a yawn than in the spirit of stretching. Like the Trauma Reflex, everyone has experienced the pandicular response. It’s the “morning stretch” – not the athletic stretch, by the way – but the sensuous strong contraction of muscles followed by an easy release. This action sends a cascade of sensory-nerves signals to the cerebral cortex of the brain (sensory and sensory-association areas) sufficient to forge or reforge the link of the sensory and motor areas of the brain – to awaken or improve voluntary control of muscles and movement – to shift control of muscles and movement from involuntary, habit-driven levels of the brain to the voluntary level. Muscles come free of contraction and so relax and lengthen.
The pandicular response is the action of awakening and refreshment of movement the way the Trauma Reflex is the action of withdrawing and protecting from pain or injury. It’s an action found among all creatures with a spinal column, including birds, horses, dogs and cats. It’s genetically inherent.
Everyone has experienced the pandicular response. What’s needed is to do it in movement patterns that involve the muscles of the trunk and legs that cause S-I joint syndrome.
For example, the action of the back muscles is to induce lumbar curve. To engage the pandicular response with these muscles, one may lie prone (belly down) and lift one leg (straight knee), then slowly lower it. The action engages the spinal extensors, gluteus maximus and hamstrings. Gravity creates the feeling of weight that causes a cascade of sensory-nerve impulses to the sensory neural network of the brain and allows us to feel the movement of lifting more vividly. The slow lowering takes allows more time, and therefore, more learning of the action of relaxation and lengthening of those muscles. Lasting changes occur rather quickly, rather than slowly.
In practice, we use a more fully elaborated set of action patterns (muscular control reconditioning exercises) that engages more of the movement system at a higher level of integration (for faster, more complete changes). For S-I joint pain, we use an array of movements that addresses all of the muscles and movements involved in S-I joint syndrome.
You may view an overview of those exercises, here.
Those movements instill healthy patterns of movement that cause the bones of the pelvis to float into a new, healthier position and that allow the S-I joints to heal.
Because of tissue changes and inflammation, healing from S-I joint pain, once the neuromuscular changes have been made, may take weeks or months. Aided and supported by somatic education exercises, they do occur. As slowly as they occur, they occur far faster and more easily than by therapeutic methods that involve strengthening, stretching, manipulation, or surgery.