psoas major


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Related to psoas major: Iliacus, psoas minor, Quadratus lumborum

psoas major

[sō′əs]
Etymology: Gk, psoa, loin
a long muscle originating from the transverse processes of the lumbar vertebrae and the fibrocartilages and sides of the vertebral bodies of the lower thoracic vertebrae and the lumbar vertebrae. It joins the iliacus to form the iliopsoas deep in the pelvis as it passes under the inguinal ligament and inserts in the lesser trochanter. It acts to flex and rotate the thigh and to flex and laterally bend the spine. Compare psoas minor.
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Psoas major and psoas minor

psoas major

medial thigh muscle
  • origin with iliacus (with which it fuses, forming iliopsoas muscle); passes into thigh posterior to inguinal ligament

  • insertion lesser trochanter

  • nerve supply ventral rami of L2 and L3

  • action iliopsoas is the chief flexor of hip joint; iliopsoas flexes trunk on thigh and medially rotates thigh of a fixed limb; iliopsoas spasm causes lateral rotation of femur and foot/leg abduction with fractured neck of femur

References in periodicals archive ?
Yoshio et al (9) also conclude that the primary role of the psoas major is lumbar stability and that it contributes very little to hip flexion.
13]C médio das rações fornecidas aos leitões durante o período experimental foi de -25,19[par mille], verifica-se que os valores das assíntotas, calculados para ambos os músculos dos animais do tratamento com 1% de glutamina (-25,25[par mille] e -25,08[par mille] para Masseter e Psoas major, respectivamente), encontramse dentro do esperado.
2011), and also lower than the values reported for the longissimus dorsi, semitendinosus, semimembranosus, psoas major and minor, and biceps femoris muscles of 15-mo-old male and female foals (Lorenzo et al.
2011) encontraron 204 genes diferencialmente expresados (DE) entre los musculos Psoas major y Flexor digitorum en ANI, musculos que son distintos desde el punto de vista histologico, metabolico y bioquimico (Moreno-Sanchez et al.
It is formed within the psoas major muscle, descends posterolaterally through the pelvis lateral to the femoral artery and vein, and then branches into terminal nerves that supply musculoskeletal structures that allow for thigh flexion, abduction, and lateral rotation from the hip joint.
Weakness with manual muscle testing was revealed in the left psoas major, quadriceps, adductors, gluteus maximus and bilateral hamstrings.
Apart from the above two branches, it gives small branches to psoas major muscle and neighboring lymph nodes.
The right superior testicular artery took origin at the normal level and crossed right ureter, right psoas major muscle and inferior vena cava while the right inferior testicular artery took origin 3 cm below the superior testicular artery above bifurcation of abdominal aorta and crossed right common iliac artery.
Ten muscles namely; Semimembranosus, Semitendinosus, Gluteobiceps, Vastus lateralis, Rectus abdominis, Longismuss dorsi (LD), Psoas major, Supraspinatus, Infraspinatus, and Triceps branchii were excised from the left half of carcasses 6 h post-mortem (PM).
psoas major (PM), with the aim of illustrating muscle specific transcription patterns and changes in connectivity regarding the expected gene co-expression patterns.