Abdomen Muscles - Anatomy Class

ABDOME MUSCLES

The muscles of the abdomen can be divided into 4 regions:

Anterolateral Region
Later Region
Upper Region
Lower Region

Anterolateral Region		Later Region
Anterior rectum of the abdomen Pyramid of the abdomen External Oblique of Abdomen Abdomen Internal Oblique Abdomen Transverse		Lumbar Square Iliopsoas Psoas Minor

Upper Region		Lower Region
Diaphragm		Anus lifter Ischiococcygeal

Anterolateral Region

1. PREVIOUS STRAIGHT OF ABDOME

Superior Insertion: External and inferior face of the 5th to 7th costal cartilages and xiphoid process

Lower Insertion: Body of the pubis and symphysis pubis

Innervation: Last 5 intercostal nerves

Action: Increased intra-abdominal pressure (Exhalation, Vomiting, Defecation, Urination and Childbirth)

* Chest Fixed: Retroversion of the pelvis

* Fixed in the Pelvis: Trunk flexion (+ or ≤ 30 °)

2. Abdominal Pyramidal

Superior Insertion: Alba Line

Lower Insertion: Body of the pubis and anterior pubic ligament

Innervation: 12th intercostal nerve

Action: Intend Alba Line

3. EXTERNAL OBLIGO OF ABDOME

Superior Insertion: External face of the last 7 ribs

Lower Insertion: ½ anterior iliac crest, EIAS, pubis tubercle and alba line

Innervation: 4 last intercostal nerves, iliohypogastric and ilioguinal nerves

Action:

* Unilateral contraction: Rotation with chest rotating to the opposite side

* Bilateral contraction: Trunk flexion and increased intra-abdominal pressure

4. INTERNAL OBLIGO OF ABDOME

Superior Insertion: 3 last costal cartilages, pubis crest and alba line

Lower Insertion: Iliac Crest, EIAS and Inguinal Ligament

Innervation: 4 last intercostal nerves, iliohypogastric and ilioguinal nerves

Action: Same as External Oblique, but rotates chest to same side

5. ABDOME TRANSVERSE

Posterior Insertion: Internal face of the last 6 costal cartilages, thoracolumbar fascia, iliac crest and inguinal ligament

Previous Insert: Alba line and crest of the pubis

Innervation: Last 5 intercostal, iliohypogastric and ilioguinal nerve

Action: Increased intra-abdominal pressure and stabilization of the lumbar spine

Later Region

1. SQUARE LOMBAR

Superior Insertion: 12th rib and transverse process from 1st to 4th lumbar vertebrae

Lower Insertion: Iliac Crest and Ileolumbar Ligament

Innervation: 12th intercostal nerve and L1

Action: Homolateral trunk inclination and 12th rib depression

2. ILIOPSOAS

Iliac

Superior Insertion: 2/3 superiors of the iliac fossa, iliac crest and sacrum's wing

Lower Insertion: Smaller trochanter

Innervation: Femoral Nerve (L2 & #8211; L3)

Action: Hip flexion, pelvic anteroversion and lumbar spine flexion (30 ° & #8211; 90 °)

Psoas Maior

Superior Insertion: Transverse process of lumbar vertebrae, bodies and intervertebral discs of the last thoracic and all lumbar

Lower Insertion: Smaller trochanter

Innervation: Upper and lower nerve of psoas major muscle (L1 & #8211; L3)

Action: Thigh flexion, lumbar spine flexion (30 ° & #8211; 90 °) and homolateral inclination

3. SMALLER PEOPLE (Usually absent)

Superior Insertion: T12 and L1 vertebral body

Lower Insertion: Iliopectinine Eminence

Innervation: L1

Action: Pelvic flexion and lumbar spine

Upper Region

1. DIAPHRAGM

Source: Inner face of the last 6 ribs, inner face of the xiphoid process and vertebral bodies of the upper lumbar vertebrae

Insertion: In the central tendon (aponeurosis)

Innervation: Phrenic Nerve (C3 & #8211; C5) and last 6 intercostal nerves (proprioception)

Action: Inspiratory as it decreases the internal pressure of the rib cage allowing air to enter the lungs, spinal stabilization and expulsions (defecation, vomiting, urination and childbirth).

Lower Region

1. ANUS LIFT

The levator usually shows a two-part separation:
– Pubococcygeal
& #8211; Iliococcygeal

Source: Between the upper branch of the pubis and sciatic spine

Insertion: Coccyx, sphincter of anus and central tendon point of perineum
Innervation: Plexus Pudding (S3 & #8211; S5)

Action: Supports and slightly elevates pelvic floor, resisting increased intra-abdominal pressure, as during forced expiration

2. ISCHIOCOCCIGE

Source: Apex of the ischium spine and sacrospinous ligament

Insertion: Coccyx margin and lateral aspect of sacrum

Innervation: Plexus Pudding (S4 & #8211; S5)

Action: Traction of the coccyx ventrally, supporting the pelvic floor against intra-abdominal pressure

ABDOME MUSCLES
Previous View & #8211; Surface layer