Muscles of the Abdomen Flashcards
Diaphragm
O (Costal) : Internal surface of ribs 7-12 and their costal cartilage
O (Sternal) : Internal surface of the xiphoid process
O (Lumbar) : L1-L3 via medial and lateral arcuate ligaments and right and left cura tendons
I : Central tendon (dome) of the diaphragm
A :
1. Increases the volume (expands) the thoracic cavity via abdominal breathing
Rectus Abdominis
O : Pubic crest and pubic symphysis
I : Xiphoid process and cartilage of ribs 5-7
A :
1. Flex the trunk at the spinal joints
2. Laterally flexes the trunk at the spinal joints
External Abdominal Obliques
O : Anterior part of the iliac crest, pubic crest and tubercle and the abdominal aponeurosis
I : Inferior border of ribs 5-12
A :
1. Flexes the trunk at the spinal joints
2. Laterally flexes at the spinal joints
3. Contralaterally rotates the trunk at the spinal joints
Internal Abdominal Obliques
O : Lateral 2/3 of the inguinal ligament, iliac crest and thoracolumbar aponeurosis
I : Internal surfaces of ribs 10-12 and the abdominal aponeurosis
A :
1. Flexes the trunk at the spinal joints
2. Laterally flexes the trunk at the spinal joints
3. Ipsilaterally rotate the trunk at the spinal joints
Transversus Abdominis
O : Lateral 2/3 of the inguinal ligament, iliac crest, thoracolumbar aponeurosis and lower 6 costal cartilage
I : Abdominal aponeurosis
A : Compresses abdominopelvic cavity
PSOAS Major
O : Anterolateral aspect of bodies T12-L5, including intervertebral discs between and anterior aspect of TVPs of L1-L5
I : Lesser trochanter of the femur
A :
1. Flexes the thigh at the hip joint
2. Laterally rotates the thigh at the hip joint
3. Posteriorly tilts the pelvis at the LS joint
Iliacus
O : Upper 2/3 of the iliac fossa and anterior inferior iliac spine and the sacral ala
I : Lesser trochanter of the femur
A :
1. Flexes the thigh at the hip joint
2. Laterally rotates the thigh at the hip joint
