Embryologically, connective tissue is one of four “tissue types” which together make up the entire body. The other tissue types are muscle, nerve, and epithelial tissues. Connective tissue is classified as either general or specialized. General connective tissue differentiates into fascia, ligaments, tendons, and joint capsules. Specialized connective tissues differentiate into cartilage, bone, and blood cells. This article will discuss the fascia related to the psoas muscle. After this review, some suggestions regarding how to work with the psoas muscle using this understanding will be discussed.

The study of the human body has a long history. Much of that history has focused on everything but the fascia. As a result, anatomy is taught, even in many schools of structural integration, from a perspective of musculoskeletal anatomy. My basic training as a practitioner was taught according to this method – attention to the musculoskeletal model and little attention to the connective-tissue matrix model.

Review of Named Fascial Layers Related to the Psoas

We will discuss the following fascial layers and their relationship to the psoas muscle:

 

. Iliac fascia

 

. Anterior, middle and posterior lamina of the thoracolumbar fascia

 

. Transversus fascia

 

. Rectus sheath

 

Iliac Fascia

 

The iliac fascia covers the iliacus and psoas muscles.

 

Relationships in the connective-tissue matrix: Iliacus fascia is derived from connective tissue. As mentioned above, other forms of connective tissue include bone and ligament. Here we will describe where in the connective-tissue matrix the iliacus fascia “ends” in bone or ligament.

The iliac fascia transforms into bone or ligament at the following places:

 

. Lumbar spine

 

-bodies of first and second lumbar vertebrae

 

-transverse process of first lumbar vertebrae

 

. Pelvis (inominate bone)

 

-inner lip of iliac crest

 

-pelvic brim

 

-iliopubic eminence

 

-pecten of the pubis

 

. Ligamentous

 

-arcuate ligament of lumbar spine

 

-posterior margin of the inguinal ligament

 

There are other places in the connective-tissue matrix where the iliac fascia continues on as fascia, however it is no longer covering the muscles named above – iliacus or psoas – and thus changes its name. At these places the fascial layer is known as:

 

. Anterior lamina of thoracolumbar fascia (see below)

 

. Transversus fascia (see below)

 

. Obturator fascia (not discussed in this article)

 

Anterior, Middle, and Posterior Lamina of Thoracolumbar Fascia

 

The thoracolumbar fascia (aka lumbodorsal fascia or LDF) has three layers or lamina: the anterior, the middle, and the posterior lamina of LDF. All three lamina have an anchor in the connective-tissue matrix at the crest of the ilium as follows:

 

. Posterior lamina attaches to the outer lip of the iliac crest.

 

. Middle lamina attaches to the very top of the iliac crest.

 

. Anterior lamina attaches to the inner lip of the iliac crest (it is continuous here inferiorly with the aforementioned iliacus fascia).

 

The posterior lamina of the LDF covers the erector spinae. This article will not cover in detail anything further regarding the posterior lamina of the LDF.

The middle and anterior lamina of the LDF envelop the quadratus lumborum muscle. The middle lamina provides the fascial layer covering the posterior aspect of the muscle while the anterior lamina provides the fascial layer covering the anterior aspect of the muscle.

Relationships in the connective-tissue matrix: Both layers of fascia (anterior and middle lamina of LDF) transform into bone or ligament at the following places:

 

. Transverse processes of L1 – L5

 

. Twelth rib (inferior border)

 

. Iliac crest (see above for specific site of attachment to the crest for each lamina)

 

As these two lamina of the LDF meet at the lateral boarder of the quadratus lumborum, the fascia changes its name and becomes the transversus fascia (see below).

 

Transversus Fascia

 

The transversus fascia lies deep to the transversus abdominis muscle.

 

Osseous, ligamentous, and fascial continuities are as follows:

 

. Ilium: at the crest between the muscular attachments of transversus and iliacus

 

. Inguinal ligament at the posterior margin

 

. Iliac fascia

 

. Anterior lamina of the LDF

 

. Rectus sheath (see below)

 

At the lateral border of the quadratus lumborum, the transversus fascia divides into two layers and changes its name. The anterior layer, which covers the anterior surface of the quadratus lumborum, is known as the anterior lamina of the LDF (see above), and the posterior layer, which covers the posterior surface of the quadratus lumborum, is known as the posterior lamina of the LDF (see above).

 

Rectus Sheath

The rectus sheath is the connective tissue covering of the rectus abdominis muscle. It is formed by the aponeurosis of the internal oblique, external oblique, and transversus abdominis muscles. The sheath extends superiorly to the costal margin and inferiorly to the midpoint between the umbilicus and interpubic disc – the acus tendineus. The posterior wall of the rectus sheath is formed by the internal oblique and transversus abdominis muscles (and their respective associated fascial layers). Given that these muscles are very thin, palpating the lateral border of the rectus sheath to the underneath side is in an effective way of contacting the transversus fascia.

 

Working with the Psoas Via the Connective-Tissue Matrix

Psoas work is a very important aspect of Rolfing Structural Integration. However, it is not always necessary to touch the psoas to be effective. Having an appreciation of the connective-tissue matrix and its relationship to the psoas muscle allows practitioners subtle and powerful means to “work with the psoas.” Furthermore, practitioners are becoming more and more sophisticated in the utilization of movement principals, specifically coordination and perception, to enhance their work with clients.

In closing, we will discuss a few aspects that practitioners may utilize to effectively work with the psoas, incorporating an understanding of fascial layers and movement principles.

 

Positional Strategies and Movement Concepts

Here we will discuss two different positional strategies and the movement concepts related to each position.

Position 1: Hook Lying. This is a position where the client is supine with the knees up, feet flat on the table. Movement concepts related to this positional strategy for psoas work include calling for movement (coordination) and inviting body awareness (perception). Begin by inviting the client to feel his feet on the table (perceptual awareness) and to gently press into the table with the whole foot (coordinative pattern). This may help the client and practitioner to begin to feel the activation of transversus abdominis. As the client engages the transversus the practitioner may now invite a slow gentle movement through the axial complex by asking the client to curl his tail toward the ceiling. This needs to be a slow and easy “call to movement.” The practitioner is now assisting the client to discover new possibilities of coordination involving psoas in balance with rectus femoris, rectus abdominis, and piriformis. These types of explorations of micromovement can be seen as assisting the client to develop a new anticipatory postural activity (APA) to support further motor programming. As the practitioner and client are able to perceive a degree of success with this movement pattern, more complex movements may be added such as slowly raising one foot off from the table or sliding the foot down the table, movements involving contraction of the psoas. Practitioners can look for pelvic stability during these more complex movement patterns. If the practitioner notices a lack of stability through the pelvis – for example, tilt, shift, rotation, or torsion of the pelvis – during this movement invitation, it may be best to go back to the prior step to establish better activation of transversus.

Position 2: 1/2 Hook Lying. This is a position where the client is supine with one knee up, foot flat on the table, and the other leg stretched out. The movement pattern would be the same as above – however, now the activation of transversus will come primarily from the foot in contact with the table, and the activation of the psoas will come from the leg that is lying straight on the table. The call for movement will consist of a small invitation for knee flexion of the straight leg. Again, if there is a lack of pelvic stability the practitioner may wish to return to the activity described above in Position 1, and assist the client in his ability to perceive pelvic stability prior to proceeding with Position 2.

 

Incorporating Fascial Layers into Psoas Work

Practitioners may further enhance the effectiveness of their work with clients through their hands-on skills. While attending to the positional strategies and movement concepts described above, a practitioner may also work with his client from a fascial-layers perspective. Potent areas to contact include:

Rectus Sheath. Contacting the rectus sheath with the intent of gently finding the underside surface gives the practitioner direct contact with the transversus fascia (see rectus sheath above). By contacting the transversus fascia the practitioner can feel through the fascial layers – actually one continuous layer that changes its name from transversus fascia to anterior lamina of LDF to iliac fascia (covering the psoas muscle). By contacting the rectus sheath in this way and asking for movement as described above, the practitioner is effectively working with the psoas and the client is enhancing his coordinative and perceptive reality.

Crest of Ilium. Contacting the crest of the ilium (client in hook lying position, see above) at the point superior to the anterior superior iliac spine, the practitioner is able to fairly easily and gently explore the contour of this aspect of the client’s ilium. Explore in particular the inside aspect of this point on the ilium just above the inguinal ligament. As you come into the bowl of the pelvis from this point, know that you are now on the iliac fascia, the fascia that covers the iliacus and psoas muscles. Therefore, the intention of the practitioner can be to affect the psoas with a clear line of contact. If the practitioner stays on this inner surface of the ilium and brings his touch to just above the crest, his direct touch is now where the iliac fascia has transitioned into the transversus fascia. Once again the practitioner can follow the connective-tissue matrix from transversus fascia to the anterior lamina of the LDF to the iliac fascia (covering the psoas muscle). Again, by contacting the tissues in this way and asking for movement, the practitioner is effectively working with the psoas and the client is enhancing his coordinative and perceptive reality.

 

References

 

– Sweeney, Lauren J., Basic Concepts in Embryology: A Student’s Survival Guide. New York: McGraw-Hill, 1998.

 

– 3D Human Anatomy: Regional Edition (DVD). Primal Pictures, www.primalpictures.com, 2005.The Connective-Tissue Matrix and the Psoas Muscle[:]