Psoas minor muscle

Psoas minor muscle
Lumbar and thigh muscles
origin
12th thoracic and 1st lumbar vertebrae
approach
with arcus iliopectineus and eminentia iliopubica of the pubic bone
function
Lumbar spine : flexion ( inclination ) and lateral inclination ( lateral flexion )
Innervation
Iliohypogastric nerve
Spinal segments
L1 and L2

The psoas minor muscle ( Latin for "small lumbar muscle") is a skeletal muscle of the lower extremity , more precisely the front ( ventral ) layer of the rear ( dorsal ) hip muscles. In humans it is inconsistent; depending on the author, it is developed in 30 to 50% of individuals. It is functionally combined with the large lumbar muscle ( psoas major muscle ) and the iliac muscle ( iliacus muscle ) to form the lumbar and iliac muscle ( iliopsoas muscle ).

course

The origin of the small lumbar muscle are the twelfth thoracic vertebra - and the first lumbar vertebra .

It radiates with a long tendon into the muscle band ( fascia iliaca ), which surrounds it together with the large lumbar muscle and the iliac muscle, in particular into the arched ligament ( arcus iliopectineus ) between the inguinal ligament ( ligamentum inguinale ) and the eminentia iliopubica of the pubic bone .

In quadruped mammals , the muscle attaches independently of the lumbar iliac muscle to a small hump ( tuberculum musculi psoas minoris ) on the iliac bone .

function

The effect of the small lumbar muscle as a single muscle is of no great importance. With one-sided tension it causes a sideways inclination ( lateral flexion ) and with bilateral tension it causes a flexion ( inclination ) in the lumbar spine .

Clinical significance

In the house cat , the muscle shows up in a lateral view of the rib cage as a soft tissue shadow, which leads to an apparent displacement of the upper rear edge of the lungs from the spine.

Individual evidence

1. ^ Wayne Vogl, Adam WM Mitchell: Anatomy for Students . Elsevier, Urban & Fischer-Verlag, 2007, ISBN 978-3-437-41231-8 , p. 324.
2. ↑ Waldeyer anatomy of man. 17th edition. Walter de Gruyter, 2002, ISBN 3-11-016561-9 , p. 1139.
3. ↑ Ursula Wappelhorst among other things: Text and workbook functional anatomy . Elsevier, Urban & Fischer-Verlag 2005, ISBN 3-437-48030-8 , p. 219.
4. ↑ Franz-Viktor Salomon: muscle tissue. In: Anatomy for veterinary medicine. 2nd ext. Edition. Enke, Stuttgart 2008, ISBN 978-3-8304-1075-1 , pp. 147-234.
5. ↑ Heike Karpenstein: Radiographic pulmonary diagnostics. In: Small Animal Medicine. 5-2013, pp. 240-248.