The Deep Six, Part II
Anatomist’s Corner
By Thomas Myers
Illustrations by Andrew Mannie
Originally published in Massage & Bodywork magazine, August/September 2003.
Copyright 2003. Associated Bodywork and Massage Professionals. All rights reserved.
Last time, we considered the lateral rotators deep behind the hip, and we didn't have a lot of good things to say about them. Oh, they're important enough, alright -- they stabilize the bottom of the spine and pelvis to the femur, obviously, and they lock and unlock the sacrum in the sacroiliac joint. They help us change direction by orienting the knee and foot to the direction we want our pelvis to go. And they keep the spine extended by holding the ischial tuberosities close to the back of the greater trochanter. In this way, these deep lateral rotators are antagonists to the string and numerous hip flexors, like the iliopsoas, pectineus and several of the adductors.
But they are difficult to feel (and therefore to treat), being six small muscles underneath the fairly thick gluteus maximus. They also have individualized functions that are hard to remember or even understand. And they carry a heavy psychosomatic load, "bringing up the rear" as it were, with all of their associated issues concerning control, being "up tight," and dominance and submission.
This issue, we will continue our exploration with specific palpation and treatment options for this essential but problematic little set of muscles. First, we need to mentally remove the gluteus maximus, which overlies all of these muscles. For our purposes, this muscle is not really part of the group we are studying, and should in any case be divided into two muscles -- gluteus "north" and gluteus "south" -- OK, superior and inferior. The superior part originates on the iliac crest near the posterior superior iliac spine (PSIS), and inserts into the posterior iliotibial tract (see Figure 1). Therefore, this part of the muscle is entirely appendicular, meaning confined to the leg, and acts as the posterior part of the "deltoid of the hip," as an abductor and lateral rotator. The inferior part originates from the sacrum and sacrotuberous ligament, and inserts into the femoral shaft well below the trochanter, making it both an axial-appendicular connector, as well as a stair-climbing hip extensor.
We noted before that the "deep six," under the gluteus, are part of a larger fan of muscles centered around the greater trochanter. This fan starts in the front of the hip with the tensor fasciae latae and the gluteus medius and minimus, and ending with the quadratus femoris. Let's start with the last of the gluteals, the trailing edge of the gluteus medius, as students often confuse it with one of the real deep six.
To find the first of these muscles under the gluteus, find the PSIS on your prone model (this is the lump of bone under the dimple at the back end of the iliac crest). Now find the top of the trochanter, which can be located on even fairly overweight clients by pushing down the lateral line from the iliac crest. Once you locate these two points, the trailing edge of the gluteus medius runs between them. Strum across the line between the two landmarks and you will likely feel, under the gluteur maximus, a strong bass string thumping beneath your fingers. This is the posterior gluteus medius.
Once located, and determined to be in need of treatment, you can take any of several good approaches to this area. Cross-fiber friction, muscle-energy, positional release, trigger-point therapy, myofascial release -- many methods work. Attention, however applied, may be the most fundamental therapy of all, breaking the cycle of non-feeling, termed by Thomas Hanna (creator of Hanna Somatics) as "sensorimotor amnesia."
But be careful how you do this, because this muscle is often tight in self-defense, eccentrically loaded (strained, or "locked-long") by extra contraction or shortness in the medial rotators (like the tensor fasciae latae, or TFL), or the hip flexors (including the TFL, but iliacus, psoas and pectineus as well). Sometimes you can ease the gluteus medius simply by lengthening the antagonistic muscles in the front. Ease the strain in the back without easing the corresponding strain in front, and the person will feel better only until they look and feel worse.
This edge of the gluteus medius is sometimes confused with the piriformis, which has a very different set of functions, and is located in a slightly lower, but still precisely locatable, place. To find the piriformis, put one finger at the sacrolumbar junction -- the last gap you can feel between the spinous processes at the base of the spine -- and your thumb at the sacrum-tailbone junction. Locate the top of the trochanter again with the finger of your other hand. See the triangle you've made? The easiest place of access for the piriformis is right in the center of that triangle. Closer to the midline, the muscle dives deep under (anterior to) the sacrum, and cannot be reached. Closer to the trochanter, the tendon gets tiny and blends with others as it nears the bone -- likewise hard to feel. The track of the piriformis is about horizontal, but more often a bit downward from the sacrum to the trochanter.
Keeping Balance
The piriformis performs lots of roles. It is a principal stabilizer of the bottom of the spine. The spine is a long yardstick, with a heavy head on top, kind of like an upside-down broom. Consider balancing an upside-down broom in the palm of your hand. To keep the broom up there, you have to make precise little compensatory motions with your hand. The role of the piriformis is similar, though a little modified: The spine sits into the sacroiliac (SI) joint and the piriformis is plastered onto the front of the sacrum just below this joint. Therefore, the piriformis can counterbalance the spine. If the spine, for instance, leans to the left, the tailbone and sacrum below the SI joint would want to move to the right. The left piriformis would tense to prevent this from happening. None of the other muscles of this group attach to the sacrum, so this role is unique to the piriformis.
But that's not the only role. The piriformis also acts to approximate the two bones of the SI joint, locking them together while the hip is in the supporting phase of gait. So we expect the piriformii to alternate contractions, releasing when the leg is swinging forward into flexion, allowing the ilium to posteriorly tilt on the sacrum at the SI joint, and then contracting strongly at heel strike, holding the joint in solid apposition while the loaded femur swings back into extension.
There is one more factor related to the piriformis' connection to sacrum. The SI joint not uncommonly gets locked at one end or the other of its movement. The shorter fibers of the psoas, acting via L5, tend to take the sacrum into nutation (an anterior tilt). The piriformis, because of its location below the SI joint, tends to take the sacrum into counter-nutation (as if tucking the tail under). If the joint is hypermobile, or locks into one end of its movement or the other, both these muscles can freeze in an attempt to keep the joint from being a painful bearing spot.
All this points toward the realization that the piriformis may be one of the harder muscles to keep balanced, and indeed that is my experience. Although it is certainly worthwhile to wake it up and try to keep it in balance with the rest of your structural and manual work, it probably won't stay where you put it, or stop spazzing out, until the rest of the pelvis and low back structure are in a pretty easy balance.
Hip Thruster/Posterior Tilter
Just below the piriformis come two small muscles surrounding another important pelvic stabilizer. The gemelli -- gemellus superior and inferior, but known familiarly in our school as the Gemelli brothers, Vito and Luigi -- pass from the hip bone to the posterior trochanter. In fact, they tuck right into the trochanteric fossa under the edge. Since these two small muscles flank either side of the obturatur internus, and tend to mimic its function on the hip, we will not bother with them much. We should note, however, that they each originate from the distal ends of two important ligaments (see Figures 2 and 3). The proximal attachment of gemellus superior blends with the distal attachment of the sacrospinous ligament, making gemellus a kind of muscular extension of the ligament. The gemellus inferior has a similar relationship with the sacrotuberous ligament. This writer cannot vouch for the importance of the ligamentous relationship, and has never discovered a way to gain therapeutic profit from it. But it is interesting nevertheless.
Between the two gemelli comes the tendon of the obturatur internus (OI), another important muscle we must pause to consider. The OI looks as small as the gemilli in depictions of the deep back of the hip (see Figure 2 or 7), and you could be forgiven questioning my interest in it if this is the only view you look at. From this view, the OI is small, sandwiched in between the two gemelli, and indeed, these three tendons often glom together to act as one larger myofascial unit.
But the OI outdistances the gemelli, as it turns a sharp corner around the back of the IT, between the two ligaments we just mentioned. Once the tiny tendon has turned the corner, the muscle fans out into a fairly large and thick muscle that covers the entire inside of the lower ischio-pubic flange of the hip bone (see Figures 7 and 8). That's the part with the hole in it. In your body, the hole is closed in (obdurate) by a tough membrane, and the obturatur internus fastens to the inside of this membrane (and the surrounding bone), while the obturator externus clings to the outside.
OI is very active in maintaining hip extension in the manner we explored last column. If both sides contract, it is a powerful hip thruster in action, or a powerful posterior tilter of the pelvis in posture. Flat backs and flat rear ends will often show chronic and serious contraction in these muscles and will function better with these muscles released.
To find this muscle with surety, lay your client supine and locate her ischial tuberosity (IT) from the bottom, just above the gluteal fold. Walk your fingers straight up the IT, toward your client's head. As the IT "levels out," you will feel a soft bit of muscle between your fingers and the bone. That muscle is the OI as it turns the corner between the parts shown in Figure 7 and Figure 8. It runs straight out horizontally from this point toward the trochanter.
Lining the inside of the true pelvis as it does, the OI plays host to the pelvic floor. The hammock of the pelvic floor reaches out to the side and grabs onto the fascia of the OI, as there is nothing else for it to do. This implicates the OI as part of the problem and the solution in pelvic floor deficiencies. The clinical implications of this will have to wait until we meet some day in class, as these maneuvers are too delicate to work from a verbal description. But if you know your way around this area, you can conceivably affect menstrual pains, post-partum deficiencies and those "up tight" folks we were talking about before.
Dynamic Duo
Two muscles remain in our tour -- the obturatur externus and the quadratus femoris. The quadratus is a small but powerful square muscle that goes from the outside of the ischial tuberosity to the lower part of the posterior surface of the greater trochanter. Palpating up and down on the back of the trochanter just lateral to the IT will often reveal not a twangy guitar string, like the others, but a mound of soft muscle. Don't let the softness fool you, this little feller is a powerful component in posterior (tail-tucked) pelves and can often benefit from some sustained, slow work with an elbow or a knuckle (see Figure 7 for a view of this muscle).
Obturatur externus, the last muscle of our long tour, is quite hard to reach for direct palpation or treatment, but it is very interesting. It is the only one of the lateral rotators which acts as a hip flexor, which means it can counteract the tendency of the others to extend the hip while laterally rotating, passing from the outside of the lower flange of the hip bone (both obturaturs are separated only by the obturatur membrane that cover the familiar hole in the lower pelvis bone) under the neck of the femur to the posterior trochanteric fossa. In my experience, only the very front of the belly of the muscle can be palpated, and even that has to be through the pectineus, and so close to the pubic bone as to be "touchy" in most people. We will have to content ourselves with Figure 9, and the knowledge that this muscle can be stretched with manual assistance that extends and medially rotates the hip joint.
Here endeth our tour of the deep lateral rotators -- an interesting and crowded little piece of real estate. Altogether, these special little muscles will amply repay the time and attention you give them in your treatment room.
Thomas Myers, Certified Advanced Rolfer, L.M.T., N.C.T.M.B., 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 therapies. He served as a founding member of the NCBTMB and as a chair of the Rolf Institute's anatomy faculty. His articles have appeared in a number of magazines, and his book on myofascial continuities, Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists, was published in 2001 by Harcourt Brace. Myers retains a strong interest in perinatal and developmental issues around movement. His practice combines structural integration, physiological rhythmic sensitivity and movement. He lives, writes and sails on the coast of Maine.
Originally published in Massage & Bodywork magazine, August/September 2003.
Copyright 2003. Associated Bodywork and Massage Professionals. All rights reserved.
 The gluteus muscle should really be considered as two separate muscles--the superior portion goes from the posterior superior iliac spine (PSIS) of the hip bone to the illiotibial band, while the inferior portion connects the spine to the shaft of the femur. |
But they are difficult to feel (and therefore to treat), being six small muscles underneath the fairly thick gluteus maximus. They also have individualized functions that are hard to remember or even understand. And they carry a heavy psychosomatic load, "bringing up the rear" as it were, with all of their associated issues concerning control, being "up tight," and dominance and submission.
This issue, we will continue our exploration with specific palpation and treatment options for this essential but problematic little set of muscles. First, we need to mentally remove the gluteus maximus, which overlies all of these muscles. For our purposes, this muscle is not really part of the group we are studying, and should in any case be divided into two muscles -- gluteus "north" and gluteus "south" -- OK, superior and inferior. The superior part originates on the iliac crest near the posterior superior iliac spine (PSIS), and inserts into the posterior iliotibial tract (see Figure 1). Therefore, this part of the muscle is entirely appendicular, meaning confined to the leg, and acts as the posterior part of the "deltoid of the hip," as an abductor and lateral rotator. The inferior part originates from the sacrum and sacrotuberous ligament, and inserts into the femoral shaft well below the trochanter, making it both an axial-appendicular connector, as well as a stair-climbing hip extensor.
We noted before that the "deep six," under the gluteus, are part of a larger fan of muscles centered around the greater trochanter. This fan starts in the front of the hip with the tensor fasciae latae and the gluteus medius and minimus, and ending with the quadratus femoris. Let's start with the last of the gluteals, the trailing edge of the gluteus medius, as students often confuse it with one of the real deep six.
 Figure 2: Locate the posterior edge of gluteus medius between the PSIS and the top of the greater trochanter. |
Once located, and determined to be in need of treatment, you can take any of several good approaches to this area. Cross-fiber friction, muscle-energy, positional release, trigger-point therapy, myofascial release -- many methods work. Attention, however applied, may be the most fundamental therapy of all, breaking the cycle of non-feeling, termed by Thomas Hanna (creator of Hanna Somatics) as "sensorimotor amnesia."
But be careful how you do this, because this muscle is often tight in self-defense, eccentrically loaded (strained, or "locked-long") by extra contraction or shortness in the medial rotators (like the tensor fasciae latae, or TFL), or the hip flexors (including the TFL, but iliacus, psoas and pectineus as well). Sometimes you can ease the gluteus medius simply by lengthening the antagonistic muscles in the front. Ease the strain in the back without easing the corresponding strain in front, and the person will feel better only until they look and feel worse.
 Figure 3: Form a triangle between the top of the trochanter and the top of the bottom of the sacrum, and the easiest place to access piriformis will be in the middle of the triangle. |
Keeping Balance
The piriformis performs lots of roles. It is a principal stabilizer of the bottom of the spine. The spine is a long yardstick, with a heavy head on top, kind of like an upside-down broom. Consider balancing an upside-down broom in the palm of your hand. To keep the broom up there, you have to make precise little compensatory motions with your hand. The role of the piriformis is similar, though a little modified: The spine sits into the sacroiliac (SI) joint and the piriformis is plastered onto the front of the sacrum just below this joint. Therefore, the piriformis can counterbalance the spine. If the spine, for instance, leans to the left, the tailbone and sacrum below the SI joint would want to move to the right. The left piriformis would tense to prevent this from happening. None of the other muscles of this group attach to the sacrum, so this role is unique to the piriformis.
 Figure 4: The piriformis hangs onto the sacrum below the sacroiliac (SI) joint, and therefore acts to stabilize the spine, reinforcing the sacral ligaments that hold the pelvis together. The piriformis normally acts to balance the sacrum under the spine like the minor adjustments a hand makes under an upright broom. Note that as the spine leans to the left, it would the left piriformis that would lock up first, though a chronic side bend will often result in both prirformii grabbing the sacrum. |
There is one more factor related to the piriformis' connection to sacrum. The SI joint not uncommonly gets locked at one end or the other of its movement. The shorter fibers of the psoas, acting via L5, tend to take the sacrum into nutation (an anterior tilt). The piriformis, because of its location below the SI joint, tends to take the sacrum into counter-nutation (as if tucking the tail under). If the joint is hypermobile, or locks into one end of its movement or the other, both these muscles can freeze in an attempt to keep the joint from being a painful bearing spot.
 Figure 5: In walking, the piriformis on the weight-supporting foot contracts, locking the sacrum to that hip joint. The piriformis on the swinging leg relaxes, allowing limited motion in the SI joint. The hip bone moves with the femur like a pendulum hung from the 12th rib. |
Hip Thruster/Posterior Tilter
Just below the piriformis come two small muscles surrounding another important pelvic stabilizer. The gemelli -- gemellus superior and inferior, but known familiarly in our school as the Gemelli brothers, Vito and Luigi -- pass from the hip bone to the posterior trochanter. In fact, they tuck right into the trochanteric fossa under the edge. Since these two small muscles flank either side of the obturatur internus, and tend to mimic its function on the hip, we will not bother with them much. We should note, however, that they each originate from the distal ends of two important ligaments (see Figures 2 and 3). The proximal attachment of gemellus superior blends with the distal attachment of the sacrospinous ligament, making gemellus a kind of muscular extension of the ligament. The gemellus inferior has a similar relationship with the sacrotuberous ligament. This writer cannot vouch for the importance of the ligamentous relationship, and has never discovered a way to gain therapeutic profit from it. But it is interesting nevertheless.
 Figure 6: The psoas and the piriformis have an antagonistic relationship across the SI joint. This makes both among the first to go into pelvic imbalance, and the last to come back. |
But the OI outdistances the gemelli, as it turns a sharp corner around the back of the IT, between the two ligaments we just mentioned. Once the tiny tendon has turned the corner, the muscle fans out into a fairly large and thick muscle that covers the entire inside of the lower ischio-pubic flange of the hip bone (see Figures 7 and 8). That's the part with the hole in it. In your body, the hole is closed in (obdurate) by a tough membrane, and the obturatur internus fastens to the inside of this membrane (and the surrounding bone), while the obturator externus clings to the outside.
 Figure 7: The obturatur internus, seen from behind, runs parallel with two smaller muscles, the gemelli, each of which arises from the distal attachment of important pelvic ligaments. |
To find this muscle with surety, lay your client supine and locate her ischial tuberosity (IT) from the bottom, just above the gluteal fold. Walk your fingers straight up the IT, toward your client's head. As the IT "levels out," you will feel a soft bit of muscle between your fingers and the bone. That muscle is the OI as it turns the corner between the parts shown in Figure 7 and Figure 8. It runs straight out horizontally from this point toward the trochanter.
 Figure 8: Believe it or not, this is the same muscle that appears in the middle of Figure 7. After passing along the back of the hip, it turns 90 degrees into the page and fills the inside of the lower flange of the pelvic bone. Seen here from the inside, the obturatur internus (OI) lines the inside of the entire true pelvis, and then dives into this picture to join with the gemelli on the back of the hip. The dotted line shows where the pelvic floor attaches to the OI. |
Dynamic Duo
Two muscles remain in our tour -- the obturatur externus and the quadratus femoris. The quadratus is a small but powerful square muscle that goes from the outside of the ischial tuberosity to the lower part of the posterior surface of the greater trochanter. Palpating up and down on the back of the trochanter just lateral to the IT will often reveal not a twangy guitar string, like the others, but a mound of soft muscle. Don't let the softness fool you, this little feller is a powerful component in posterior (tail-tucked) pelves and can often benefit from some sustained, slow work with an elbow or a knuckle (see Figure 7 for a view of this muscle).
Obturatur externus, the last muscle of our long tour, is quite hard to reach for direct palpation or treatment, but it is very interesting. It is the only one of the lateral rotators which acts as a hip flexor, which means it can counteract the tendency of the others to extend the hip while laterally rotating, passing from the outside of the lower flange of the hip bone (both obturaturs are separated only by the obturatur membrane that cover the familiar hole in the lower pelvis bone) under the neck of the femur to the posterior trochanteric fossa. In my experience, only the very front of the belly of the muscle can be palpated, and even that has to be through the pectineus, and so close to the pubic bone as to be "touchy" in most people. We will have to content ourselves with Figure 9, and the knowledge that this muscle can be stretched with manual assistance that extends and medially rotates the hip joint.
 The obturatur externus is an odd and inaccessible muscle that acts, as you can see here, as a trampoline for the hip joint. Unlike all these others, it also acts as a hip flexor. |
Thomas Myers, Certified Advanced Rolfer, L.M.T., N.C.T.M.B., 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 therapies. He served as a founding member of the NCBTMB and as a chair of the Rolf Institute's anatomy faculty. His articles have appeared in a number of magazines, and his book on myofascial continuities, Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists, was published in 2001 by Harcourt Brace. Myers retains a strong interest in perinatal and developmental issues around movement. His practice combines structural integration, physiological rhythmic sensitivity and movement. He lives, writes and sails on the coast of Maine.
