Anatomy revision part 1
- 1. MRCS Revision Anatomy Awesomemedicalnotes.wordpress.com
- 2. Severe haematemesis – gastric ulcer and the affected arteries • Posterior gastric ulcer – splenic artery • Lesser curve gastric ulcer – left gastric artery • Greater curve gastric ulcer – gastroepiploic artery • Posterior duodenal ulcer – gastroduodenal branch of right gastric artery • Inferior pancreaticoduodenal (branch of superior mesenteric) artery supplies lower part of 2nd part of duodenum – well clear of ulceration site • Celiac artery branches (arises from aorta at T12): – L gastric artery ( branch into oesophageal and gastric branches) – Common hepatic artery ( branch into proper hepatic artery, R gastric artery and gastroduodenal artery(branch into superior pancreaticoduodenal artery)) – Splenic artery (dorsal pancreatic artery, greater pancreatic artery, left gastro-omental artery, short gastric artery) • Superior and inferior mesenteric arteries arise from aorta at L1 and L3 respectively
- 3. Hepatic blood supply • Blood supply to liver = 25% of resting cardiac output – 25% from hepatic artery – 75% from hepatic portal vein (from GI tract and spleen) • Normal portal pressure = 5-7mmHg ( increases after meals) • Both vessels enter liver via porta hepatis. • Caudate lobe receives an independent blood supply from hepatic portal vein and artery and its branch of hepatic vein drains directly into inferior vena cava
- 4. Psoas major muscle • Flexes thigh at hip joint • It joins illiacus muscle (origin: inner aspect of iliac wing of pelvis), and becomes iliopsoas muscle and inserts on lesser trochanter of femur = flexes thigh at hip joint
- 5. Femoral sheath • Femoral sheath ends 4cm inferior to inguinal ligament • Medial wall of fem sheath is pierced by great saphenous vein and lymphatic vessels • It is divided by 2 ventral septa into 3 compartments: – Lateral (contains fem. artery) – Intermediate (contains fem. vein) – Medial (a space called fem. canal) • Fem. canal contains efferent lymphatic vessels and a lymph node • Entrance of fem canal = fem ring = site of fem hernia
- 6. Uterine Artery • Arises from internal iliac artery (may also arise from umbilical artery) • Lies anterosuperior to ureter near lateral portion of fornix – Risk of ureteric damage during hysterectomy – Esp. left ureter as it lies very close to lat. Aspect of cervix • Point of crossing b/w uterine artery and ureter = 2 cm superior to ischial spine
- 7. Pelvis
- 8. Pelvis 2
- 9. Uterus
- 10. Uterus 2 • Uterus is normally bent anteriorly b/w cervix and body of uterus • Commonly anteverted (inclined anteriorly) but frequently retroverted in older woman • 3 layers: perimetrium, myometrium and endometrium • Uterine body is enclosed b/w layers of broad ligament – freely mobile • Uterus covered by peritoneum anteriorly and superiorly except for vaginal part of cervix • Uterus is supported by pelvic floor
- 11. Hypoglossal Nerve • Supplies all intrinsic muscles of the tongue but not the palate (the palatoglossus muscle supplied by vagus nerve) • No sensory component • Genioglossus muscle protrudes the tongue • In paralysis, tongue deviates towards the affected side. (e.g. damaged left hypoglossal nerve = tongue deviates to left • Left submandibular salivary gland excision = risk of damaging hypoglossal nerve
- 13. Inferior/recurrent laryngeal nerve 2 • A branch of vagus nerve • Supplies all muscles of larynx except cricothroid muscle (supplied by superior laryngeal branch of vagus nerve) • Sensory component – supplies larynx inferior to vocal cords • Damage recurrent laryngeal nerve: – Larynx is anaesthetic inferior to vocal cord on affected side – Paralysed cord seen to lie in ‘paralytic’ position: slightly abducted from midline and does not move on phonation