The iliopsoas is a group of muscles mainly used for hip flexion. The Psoas, two muscles within this group, originates in front of (anterior to) the transverse processes of the T12 to L5 vertebrae and inserts into the lesser trochanter of the femur. (2) Simply put, it starts on the lumbar spine (as well as the last thoracic vertebrae) and connects into your upper thigh. Its predominant function is for hip flexion (bringing your knee to your chest) but, also aids in bending and twisting the trunk, as well as stabilizing the spine.
The Iliopsoas and it's Effect on the Body
The iliopsoas and specifically the psoas, plays a major part in core musculature. Early in my career instructors emphasized the importance of looking for tight iliopsoas and stretching it. This was pretty easy to spot and to test for, but it wasn’t until a couple years later I found out first hand the problems this can cause. Back pain, sacroilliac dysfunction, degenerative disc disease, groin pain, scoliosis, and more are the result or cause of tight/dysfuncitional iliopsoas muscles. (1)(2)(3). A dysfunctional iliopsoas can even cause pelvic discomfort, bowel dysfunction, burning in the thigh, groin, labia/testicle, and almost always mal posture.(3) I personally experienced some of these common symptoms like back pain sacroiliac pain, and mal posture. I even experienced intense less common symptoms that many doctors could not explain. Read more on Jerry’s experience with psoas dysfunction.
The solution to some of these problems may be complex and need much further care, but you can stretch the iliopsoas and specifically the psoas to help you with rehabilitation, post-rehabilitation and injury prevention. It is an easy and simple stretch, but there are some key points to focus on.
On a mat, set one knee down and the other leg up so you are kneeling on one knee. In this position first lean forward with your hips ALWAYS keeping your upperbody upright and NOT bending forward at the trunk. Keep your abdominals and glute on the side you are stretching engaged so that your lower back is not over arching. You should now feel a stretch in the upper thigh/hip area.(pic 1)
1) Warren Hammer, M.S., D.C., DABCO (January 31, 1992). The Psoas Syndrome. Dynamic Chiroopractic volume 10 issue 3. Retrieved from http://www.dynamicchiropractic.com/mpacms/dc/article.php?id=43076
2) Ken Rich, D.C. (February 24, 1997)The Iliopsoas Muscle – The Great Pretender. Dynamic Chiropractic, volume 15, issue 5. Retrieved from http://www.dynamicchiropractic.com/mpacms/dc/article.php?id=38131
3)John S. Gillick, MD, MPH, FACP (December 1, 2003) Ilio-psoas muscle strain – The Fillet Mignon of Back Aches. UCSD Healthcare. Retrieved from http://www.simple-ergonomics.com/pdf/Ilio-Psoas-07-2003.pdf
4) Lone Hansen, PhD, Mark de Zee, PhD, John Rasmussen, PhD, Thomas B. Andersen, PhD, Christian Wong, PhD, and Erik B. Simonsen, PhD. (2006) Psoas Major. Back Muscles in the Lumbar Spine With Reference to Biomechanical Modeling: Psoas Major. Retrieved from http://www.medscape.com/viewarticle/542466_5
5) Mark Donahoo. (January 1998) The Injury Potential of the Psoas in Race Walking. Australian Track & Field Coaches Association, Level 3 Coaching Paper. Retrieved from http://www.racewalkingwithmark.com/Level%203%20document.pdf