CC BY-NC-ND 4.0 · Revista Fisioterapia Invasiva / Journal of Invasive Techniques in Physical Therapy 2019; 02(01): 46-47
DOI: 10.1055/s-0039-1688507
Practice forum | Foro practico
Thieme Revinter Publicações Ltda Rio de Janeiro, Brazil

Sonographic Approach of the Lumbar Portion of the Psoas Muscle

Article in several languages: English | español
Jaime Ríos Serra
1  Clínica Serra, San Vicente del Raspeig, Alicante, Spain
Ana de Groot Ferrando
2  Campos Fisioterapia, Alicante, Spain
› Author Affiliations
Further Information

Publication History

Publication Date:
28 June 2019 (online)



The deep part of the psoas major muscle originates from the transverse processes of lumbar vertebrae L1 to L5, whereas the superficial part originates from the lateral surfaces of the T12 vertebral body. The muscle descends, crossing the anteromedial portion of the vertebral bodies, and, at the level of the pelvis, it joins the iliacus muscle, forming the iliopsoas muscle and inserting onto the lesser trochanter of the femur. This is the only muscle that inserts at this site, and it is innervated by the branches from the ventral rami of L1 to L4, which correspond to the crural nerve.

The iliopsoas is involved in dynamic movements such as walking and is important for the maintenance of static standing. Its primary functions include producing hip flexion (with a fixed trunk) and lumbar extension by increasing the lordosis (when the muscle contracts with fixed legs, the anterior pelvic tilt increases).[1] [2] [3] [4] Besides, this muscle has a stabilizing role for the hip and lumbar spine.[5] [6] [7] [8] [9] [10] [11] The function of the same cannot be recognized as being separate from the iliacus muscle, as demonstrated via electromyography.[12]

The aim of this study was to demonstrate a new approach for locating the muscle to enable a sonographic assessment of the lumbar origin of the psoas muscle, beginning with a basic examination in the groin region. Moreover, we sought to establish an accessible and safe sonographic approach to enable us to assess a portion of the psoas muscle, which has been poorly studied to date. Hence, this may help establish a possible evolution of lesions affecting this muscle.

This sonographic description may be relevant within the field of physiotherapy as it is an approach that is seldom used. Additionally, it provides useful information regarding the quality of the contraction of the psoas muscle along its path besides detecting changes that affect the size of the same and possible alterations in its cortical insertions. Ultimately, it allows clinicians to detect any asymmetries, as comparisons can be performed with the other psoas muscles. This can expand our sonographic assessment of this muscle.