top of page

The Iliopsoas – An MSR Approach

Updated: Apr 1

Iliopsoas muscle stretch

The iliopsoas muscle group, a vital component of the lumbar-pelvic-hip complex, is central to movement, stability, and strength in the lower body. This article delves into the complex anatomy and biomechanics of the iliopsoas, emphasizing its pivotal role within the kinetic chain and its integration within the Motion Specific Release (MSR) approach.

We will explore the iliopsoas's impact on lumbar lordosis, hip flexion, and its intricate relationship with abdominal and back musculature. The clinical significance of iliopsoas health, including common issues such as lower back pain, hip dysfunction, and postural imbalances, will be addressed. Furthermore, we will present MSR strategies tailored to improve the functionality and coordination of this muscle group, which is essential for practitioners managing intricate lumbo-pelvic conditions and enhancing core stability.

Article Index:


Anatomy Image

Anatomy & Biomechanics

The iliopsoas muscle group, essential for locomotion and postural control, is anatomically complex, consisting of the psoas major, psoas minor, and iliacus muscles.

Origin and Insertion:

  • The psoas major, a long fusiform muscle, originates from the anterolateral surfaces of the T12 to L5 vertebrae, and the associated intervertebral discs, creating a muscular sheet that passes beneath the inguinal ligament to insert on the lesser trochanter of the femur.

  • The psoas minor, when present, lies anterior to the psoas major, originating from T12 and L1 vertebrae, with a distal insertion onto the iliopectineal eminence. The iliacus originates broadly from the superior two-thirds of the iliac fossa, the iliac crest, and the lateral sacral crest, converging with the psoas major to form the iliopsoas tendon.

Innervation and Vascular Supply:

  • The psoas major's segmental innervation is via direct branches from the anterior rami of L1-L3 spinal nerves, while the iliacus receives innervation from the femoral nerve (L2-L4). This innervation pattern provides both somatic and sympathetic nerve fibers, suggesting an interrelationship between iliopsoas function and autonomic regulation.

  • The psoas minor is inconsistently present but, when available, is innervated by branches from L1. The iliopsoas is vascularized by the iliolumbar and medial circumflex femoral arteries, ensuring a rich blood supply vital for its high metabolic demands during sustained postural control and repetitive hip flexion activities.

Biomechanical Functionality:

  • Functionally, the iliopsoas is the most potent hip flexor. During gait, it facilitates the swing phase by accelerating the thigh forward. It also contributes to lateral flexion of the lumbar spine and can influence the anterior pelvic tilt due to its attachment on the lesser trochanter.

  • The psoas major plays a unique role in spinal biomechanics, as its lumbar attachments allow it to act as a stabilizer of the lumbar spine when the thigh is fixed.

  • The iliacus, with its broad pelvic attachment, assists in stabilizing the pelvis during single-leg stance and provides a firm base for the psoas major to exert its hip flexion force.

Kinetic Interactions:

  • Kinetic analysis reveals that the iliopsoas does not work in isolation. Its activity is finely coordinated with that of the abdominal muscles to control anterior pelvic tilt and lumbar lordosis. Furthermore, it must be synchronized with the gluteus maximus during gait to counterbalance anterior and posterior pelvic forces. The balance of forces between the anteriorly placed iliopsoas and the posteriorly positioned hamstrings and gluteal muscles is critical for maintaining sagittal plane stability.

MSR Implications:

  • From an MSR standpoint, the iliopsoas muscle group is a focal point for the restoration of movement integrity and neuromuscular harmony. Restrictions in the fascial tissues surrounding the iliopsoas or imbalances in muscle force generation can lead to compensatory patterns that manifest in lower limb, pelvic, and spinal dysfunctions.

  • Targeted MSR techniques aim to decompress and mobilize the iliopsoas, addressing both the myofascial and neurodynamic aspects to optimize its biomechanical efficacy. This is critical for the resolution of complex musculoskeletal syndromes that stem from or contribute to iliopsoas dysfunction.


MSR Logo

Motion Specific Release (MSR) Treatment

Initial Setup:

  • Patient Position: For comprehensive accessibility to the iliopsoas group, the patient is positioned laterally, allowing the practitioner to effectively target the iliacus and the psoas major and minor muscles.

  • Practitioner Stance: The practitioner assumes a position that offers stability and the ability to apply variable pressure, with easy access to the patient's hip and lumbar region. Optimal practitioner stance is key to effective MSR application (Refer to the associated video for visual guidance).

Basic Technique:

  • Treatment: The procedure begins with identifying crucial anatomical landmarks of the iliopsoas group. Attention is given to the origins and insertions of the psoas major, minor, and iliacus to tailor the MSR technique specifically to these structures.

  • Support Hand: The practitioner's support hand is used to stabilize the patient's limb and control the motion of the hip, guiding the iliopsoas through its functional range to enhance the release process.

  • Synchronization: The practitioner synchronizes hand movements with the patient's breathing and passive limb movements to engage the iliopsoas effectively, emphasizing neuromuscular integration during the release.

  • Pressure Application: Responsive and incremental pressure is applied using a flat hand or forearm, never the elbow, to modulate the depth and intensity of the muscle engagement, with ongoing communication to ensure patient comfort.


  • Contact: A flat hand or the broad surface of the forearm is used to maintain a broad contact area with the iliopsoas group. This technique allows for a nuanced approach to addressing the muscle fibers from various angles, ensuring a comprehensive release.

  • Combined Actions: Incorporation of the patient's arm,leg and hip movements, and including movements such as circumduction is critical to achieve and effective release.

Iliopsoas Release Procedures - MSR Demonstration:

The treatment video showcases Dr. Abelson's execution of the MSR procedures, targeting the iliopsoas group. The focus is on the psoas major's attachment points, from the lumbar vertebrae to the lesser trochanter of the femur, and the iliacus's broad origin from the iliac fossa.

Best Practices:

  • A bilateral, patient-centric approach is paramount, with an emphasis on the individual's unique musculoskeletal configuration. Treating both sides of the iliopsoas is crucial, as restrictions typically involve the entire muscle group.

Kinetic Chains:

  • The practitioner maintains an awareness of the iliopsoas' role within the kinetic chain, understanding its impact on lumbar and pelvic mechanics, thus ensuring a comprehensive treatment strategy.


  • Safety is the priority; the practitioner carefully considers any contraindications and secures informed consent before MSR application. Adjustments to pressure and movement are made in response to ongoing patient feedback, providing a customized and secure MSR experience.


Functional Kinetic Chain Image

Functional Kinetic Chains

Functional Kinetic Chains of the Iliopsoas

The iliopsoas muscle group is pivotal in the functional kinetic chains of the lower body, coordinating movements that span the lumbo-pelvic-hip complex. A thorough comprehension of the iliopsoas' integration with adjacent structures is essential for an in-depth understanding of their biomechanical and functional roles.

Direct Myofascial Connections:

The iliopsoas is deeply woven into the lower body's functional anatomy through significant myofascial continuities:

  • Lumbar Fascia: This dense connective tissue layer encapsulates the iliopsoas, linking its function to the lumbar spine's stability and movements, thereby influencing posture and lower limb mechanics.

  • Fascial Compartment: The iliopsoas resides within its own fascial compartment, which delineates it from adjacent structures such as the quadratus lumborum and pelvic muscles, allowing for precise movement control and serving as a conduit for neurovascular structures.


Muscles that collaborate with the iliopsoas include:

  • Rectus Femoris: Assists with hip flexion, working in concert with the iliopsoas during activities like running and jumping.

  • Adductor Group: Harmonizes with the iliopsoas to control hip adduction and medial rotation, contributing to the stability and movement of the lower limb.


Muscles that provide stabilization alongside the iliopsoas are:

  • Transversus Abdominis and Internal Oblique: These muscles form a force-couple with the iliopsoas, contributing to pelvic stability and assisting in maintaining lumbar lordosis.

  • Quadratus Lumborum: Offers stabilization to the lumbo-pelvic region and counteracts the forces exerted by the iliopsoas during trunk lateral flexion.


Muscles that act counter to the iliopsoas:

  • Gluteus Maximus: Opposes the iliopsoas by facilitating hip extension and posterior pelvic tilt, providing a balance in the posterior kinetic chain.

  • Hamstrings: Counterbalance the iliopsoas' hip flexion with their hip extension capability, critical for gait and postural dynamics.

MSR Perspective:

  • From the MSR viewpoint, the iliopsoas is a key component in a sophisticated biomechanical network. MSR protocols are crafted to recognize and address the intricacies within these kinetic chains. By appreciating the myofascial and neuromuscular interconnections involving the iliopsoas, MSR interventions are strategically applied to rectify dysfunctions and enhance the synchronization of movements across the lower body's kinetic chain.



Optimal conditioning of the iliopsoas complex through targeted is critical for optimal function. Flexibility exercises help to not only increase range of motion but help to mitigate potential injuries. Strength protocols are indispensable for reinforcing pelvic and lumbar stability, directly influencing athletic and functional task execution. Additionally, balance-focused regimens are crucial for cultivating proprioceptive acuity and neuromuscular synchronization, integral to dynamic stability and movement efficacy. Below are some example of exercise that could be prescribed depending on the particular case.

Effective Hip Flexor Stretches

This video demonstrates some of the most effective hip flexor stretches for both primary and secondary hip flexors. The hip flexors consist of several muscles, including the psoas and iliacus muscles, which are the primary hip flexors, and the quadriceps, which are secondary hip flexors.

Mountain Climbers (2 versions)

The Mountain Climbers Exercise is a great core stability exercise, particularly your abdominal obliques and iliopsoas complex. Great for running, because it exercises trains your body to transfer energy between the lower and upper body.

Improve Your Balance - Exercises for Beginners

Balancing exercises are crucial components in both Rehabilitation and Sports Performance training. These exercises should not be overlooked, as they can bolster one's capacity to stabilize the body during functional movements. By incorporating straightforward balance exercises into a progressive training program, you can enhance balance and avert injuries.



In summary, the iliopsoas muscle group's complexity and its significant role in the lumbo-pelvic-hip complex cannot be overstated. Through this article, we have dissected its anatomy, examined its biomechanical functionality, and highlighted the crucial role it plays in the kinetic chain. We have also discussed the profound impact of iliopsoas health on clinical presentations, from lower back pain to hip dysfunction and postural imbalances, and presented the Motion Specific Release (MSR) approach as a method to address these issues.

The MSR techniques showcased provide a roadmap for practitioners to enhance the function and coordination of the iliopsoas. By integrating these methods with a patient-centric approach, clinicians can facilitate improved outcomes in managing complex lumbo-pelvic conditions and advancing core stability. Furthermore, the exercises outlined for flexibility, strength, and balance are not just rehabilitative but are also preventative measures that can support the long-term health and functionality of the iliopsoas.



Dr. Brian Abelson Photo

Dr. Abelson's approach to musculoskeletal health care reflects a deep commitment to evidence-based practices and continuous learning. In his work at Kinetic Health in Calgary, Alberta, he focuses on integrating the latest research with a compassionate understanding of each patient's unique needs. As the Motion Specific Release (MSR) Treatment Systems developer, he views his role as both a practitioner and an educator, dedicated to sharing knowledge and techniques that can benefit the wider healthcare community. His ongoing efforts in teaching and practice aim to contribute positively to the field of musculoskeletal health, with a constant emphasis on patient-centered care and the collective advancement of treatment methods.


MSR Instructor Mike Burton Smiling

Join Us at Motion Specific Release

Enroll in our courses to master innovative soft-tissue and osseous techniques that seamlessly fit into your current clinical practice, providing your patients with substantial relief from pain and a renewed sense of functionality. Our curriculum masterfully integrates rigorous medical science with creative therapeutic paradigms, comprehensively understanding musculoskeletal diagnosis and treatment protocols.

Join MSR Pro and start tapping into the power of Motion Specific Release. Have access to:

  • Protocols: Over 250 clinical procedures with detailed video productions.

  • Examination Procedures: Over 70 orthopedic and neurological assessment videos and downloadable PDF examination forms for use in your clinical practice are coming soon.

  • Exercises: You can prescribe hundreds of Functional Exercises Videos to your patients through our downloadable prescription pads.

  • Article Library: Our Article Index Library with over 45+ of the most common MSK conditions we all see in clinical practice. This is a great opportunity to educate your patients on our processes. Each article covers basic condition information, diagnostic procedures, treatment methodologies, timelines, and exercise recommendations. All of this is in an easy-to-prescribe PDF format you can directly send to your patients.

  • Discounts: MSR Pro yearly memberships entitle you to a significant discount on our online and live courses.

Integrating MSR into your practice can significantly enhance your clinical practice. The benefits we mentioned are only a few reasons for joining our MSR team.



  1. Abelson, B., Abelson, K., & Mylonas, E. (2018, February). A Practitioner's Guide to Motion Specific Release, Functional, Successful, Easy to Implement Techniques for Musculoskeletal Injuries (1st edition). Rowan Tree Books.

  2. Cook, G. (2010). Movement: Functional Movement Systems: Screening, Assessment, Corrective Strategies. On Target Publications.

  3. Janda, V. (1983). Muscles and cervicogenic pain syndromes. In R. Grant (Ed.), Physical Therapy of the Cervical and Thoracic Spine. Churchill Livingstone.

  4. Kendall, F. P., McCreary, E. K., & Provance, P. G. (1993). Muscles: Testing and Function, with Posture and Pain (5th ed.). Lippincott Williams & Wilkins.

  5. McGill, S. M. (2015). Back Mechanic: The Step-by-step McGill Method to fix back pain. Backfitpro Inc.

  6. Myers, T. W. (2001). Anatomy Trains: Myofascial Meridians for Manual and Movement Therapists. Churchill Livingstone.

  7. Neumann, D. A. (2010). Kinesiology of the hip: A focus on muscular actions. Journal of Orthopaedic & Sports Physical Therapy, 40(2), 82-94.

  8. Page, P., Frank, C. C., & Lardner, R. (2010). Assessment and Treatment of Muscle Imbalance: The Janda Approach. Human Kinetics.

  9. Sahrmann, S. (2002). Diagnosis and Treatment of Movement Impairment Syndromes. Mosby.

  10. Standring, S. (Ed.). (2016). Gray's Anatomy: The Anatomical Basis of Clinical Practice (41st ed.). Elsevier Health Sciences.


The content on the MSR website, including articles and embedded videos, serves educational and informational purposes only. It is not a substitute for professional medical advice; only certified MSR practitioners should practice these techniques. By accessing this content, you assume full responsibility for your use of the information, acknowledging that the authors and contributors are not liable for any damages or claims that may arise.

This website does not establish a physician-patient relationship. If you have a medical concern, consult an appropriately licensed healthcare provider. Users under the age of 18 are not permitted to use the site. The MSR website may also feature links to third-party sites; however, we bear no responsibility for the content or practices of these external websites.

By using the MSR website, you agree to indemnify and hold the authors and contributors harmless from any claims, including legal fees, arising from your use of the site or violating these terms. This disclaimer constitutes part of the understanding between you and the website's authors regarding the use of the MSR website. For more information, read the full disclaimer and policies in this website.

Recent Posts

See All


bottom of page