Muscle O/I/N and nerves Flashcards
External Oblique
O: External Rib surfaces of 5-12
I: Linea Alba, pubic tubercle, ant. 1/2 iliac crest
N: Anterior Rami of T7-T11 (thoracoabdominal nerves) and subcostal nerve
Internal Oblique
O: Thoracolumbar Fascia, ant. 2/3 iliac crest, connective tissue deep to inguinal ligament
I: Inf. borders ribs 10-12, linea alba, pubis via conjoin tendon
N: Thoracoabdominal nerves (T7-T11 ant. rami) and first lumbar nerve (L1)
Transversus Abdominus
O: Internal surface ribs 7-12 costal cartilage, thoracolumbar fascia, iliac crest, connective tissue deep to inguinal ligament
I: Linea alba w/ aponeurosis of int. oblique, pubic crest, pectin pubis via conjoin tendon
N: Thoracoabdominal nerves (T7-T11) and first lumbar nerve (L1)
Rectus Abdominus
O: Pubic symphysis and pubic crest
I: Xiphoid Process and costal cartilage or 5-7
N: Thoracoabdominal nerves (Ant. rami of inf. 6 thoracic nerves)
Parietal Peritoneum Innervation
Somatic body wall nerves
Thoracoabdominal nerves
T7-T11. Continuation of lower intercostals. Run b/w 2nd and 3rd muscular layers. Lat and ant cutaneous branches enter subcutaneous tissue.
Innervate muscles of anterolateral wall and skin
Subcostal nerve
Ant ramus of T12.
Innervates anterolateral abdominal wall and overlying skin superior to iliac crest and umbilicus
Iliohypogastric nerve
L1.
Innervates skin overlying iliac crest, upper inguinal and hypogastric regions, internal oblique and transversus abdominus
Ilioinguinal nerve
L1. Passes b/w 2nd and 3rd muscular layers, then traverses inguinal canal
Innervates skin of scrotum/ labia majus and mons pubis, adjacent medial aspect of thigh, inferior most internal oblique and transversus abdominus
Pyramidalis Muscle
O: Pubic crest/symphysis
I: Linea alba
N: Subcostal (T12)
Tenses linea alba
Cremaster Muscle
N: Genital branch of genitofemoral
Dartos Muscle
N: Genital branch of genitofemoral nerve (L1-2)
Foregut innervation
Symp: T5-9 (symp chain ->greater splanchnic ->synapse in celiac ganglion -> follow celiac trunks to target organ)
Parasymp: Vagus (vagus -> through celiac plexus -> follow celiac trunks ->synapse in ganglia of gut plexuses -> short post synaptic to target organs)
Midgut innervation
Symp: T10-12 (symp chain -> lesser(T10-11)/least(T12) splanchnic -> synapse in SMA ganglion-> follow SMA trunks to target organs)
Parasymp: Vagus (vagus-> through SMA plexus->follow SMA trunks->synapse in ganglia of gut plexuses->short post synaptic to target organs)
Hindgut innervation
Symp: L1-L2 (symp trunk->lumbar splanchnic nerves (L1-L2)->synapse in IMA ganglion->post synaptic to target organs following IMA trunks
Parasymp: S2-S4 (Sacral spinal nerves S2-4 -> pelvic splanchnic -> through hypogastric and IMA plexuses -> follow branches of IMA to target -> synapse in ganglia in gut plexuses -> short post synaptic to target organs
Psoas Muscle
O:Trans processes of lumbar vert, sides of vertebral bodies and discs T12-S1
I: Lesser trochanter of femur
N: Lumbar plexus direct branches L2-4
Iliacus
O: Superior 2/3 of iliac fossa, ala of sacrum, anterior sacro-iliac ligamens
I: Lesser trochanter of femur and shaft inferior to it
N: Femoral nerve (L2-L4)