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MBBS Anatomy Examination - Complete Answers

PAPER 1 (General Anatomy + Upper Limb + Head & Neck)

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SECTION I - 50 Marks

Q1. Short Answer Questions (10 x 1 mark = 10 marks)

1. Genioglossus
2. Hyoglossus
3. Styloglossus
4. Palatoglossus

1. Maxillary sinus (via hiatus semilunaris)
2. Frontal sinus (via infundibulum)
3. Anterior ethmoidal air cells
4. Middle ethmoidal air cells (on ethmoidal bulla)

• It is a potential space where infections/hematomas can spread freely
• Extends anteriorly to eyelids, posteriorly to nape of neck
• Contains emissary veins connecting scalp veins to intracranial dural sinuses - infections can spread intracranially causing meningitis/cavernous sinus thrombosis

1. Cephalic vein
2. Thoracoacromial artery
3. Lateral pectoral nerve
4. Lymphatics from breast

• Example: Motor cells of the hypoglossal nucleus migrate to the floor of the fourth ventricle (away from the periphery), whereas sensory cells migrate towards the periphery.

1. Radial nerve
2. Profunda brachii artery (deep brachial artery)

1. Carpometacarpal joint of thumb
2. Calcaneocuboid joint

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Q2. (20 marks)

• Head of humerus (ball) - large, covered with hyaline cartilage
• Glenoid cavity of scapula (socket) - small, shallow, deepened by fibrocartilaginous glenoid labrum

1. Glenohumeral ligaments (superior, middle, inferior) - thickenings of anterior capsule
2. Coracohumeral ligament - from coracoid process to greater tuberosity; strengthens superior capsule
3. Transverse humeral ligament - bridges bicipital groove; holds tendon of long head of biceps
4. Coracoacromial ligament - forms protective arch above joint
5. Joint capsule - loose inferiorly to allow abduction

• Most commonly dislocated joint in the body - due to shallow glenoid cavity
• Anterior dislocation most common (95%): head moves anteriorly, axillary nerve/musculocutaneous nerve at risk
• Rotator cuff injury: Supraspinatus most commonly torn (painful arc 60-120°)
• Frozen shoulder (adhesive capsulitis): painful restriction of all movements
• Recurrent dislocation: Bankart lesion (labrum tear anteroinferiorly) + Hill-Sachs lesion (posterolateral humeral head compression fracture)

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• Medially: Pisiform bone and hook of hamate
• Laterally: Scaphoid tubercle and ridge of trapezium

• Superficial (anterior) to it: Ulnar nerve and artery (in Guyon's canal), palmaris longus tendon, palmar cutaneous branches of ulnar and median nerves
• Deep (posterior) to it (contents of carpal tunnel):
  • Flexor digitorum superficialis (4 tendons)
  • Flexor digitorum profundus (4 tendons)
  • Flexor pollicis longus tendon
  • Median nerve (most laterally placed)

• Compression of median nerve under the retinaculum
• Causes: Pregnancy, hypothyroidism, rheumatoid arthritis, acromegaly
• Symptoms: Pain, tingling, numbness in lateral 3.5 fingers (median nerve distribution)
• LOAF muscles wasted (Lateral two lumbricals, Opponens pollicis, Abductor pollicis brevis, Flexor pollicis brevis)
• Thenar eminence wasting
• Phalen's test and Tinel's sign positive
• Treatment: Decompression by dividing the retinaculum

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• Origin: Anterior border and upper surface of lateral 1/3 of clavicle; lateral margin of acromion; lower lip of crest of scapular spine
• Insertion: Deltoid tuberosity on middle of lateral surface of shaft of humerus

• Anterior fibers: flexion and medial rotation of arm
• Middle fibers: abduction of arm (main abductor after 15°)
• Posterior fibers: extension and lateral rotation of arm
• All fibers together: abduction from 15° to 90°

• Axillary nerve injury (common in anterior shoulder dislocation, fracture of surgical neck of humerus): deltoid paralysis causing inability to abduct arm above 15°, loss of sensation over "regimental badge" area (lateral shoulder)
• Deltoid injection site commonly used for intramuscular injections

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Q3. Short Essay Questions (4 x 5 marks = 20 marks)

1. Intermuscular septa - extend inward from deep fascia to bones, creating compartments (e.g., medial and lateral intermuscular septa of arm)
2. Retinacula - transverse thickenings that hold tendons in place (e.g., flexor and extensor retinacula at wrist and ankle)
3. Fascial sheaths - enclose individual muscles or groups
4. Pulleys - annular pulleys in fingers
5. Investing fascia - wraps around muscle groups (e.g., fascia lata of thigh)
6. Extensor expansions - on dorsum of digits
7. Iliotibial band - lateral thickening of fascia lata, extends from iliac crest to Gerdy's tubercle

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• Arterial:
  1. Perforating branches of internal thoracic (internal mammary) artery - supplies medial 2/3
  2. Lateral thoracic artery - supplies upper outer quadrant
  3. Thoracoacromial artery
  4. Posterior intercostal arteries (3rd-5th)
  5. Subscapular artery
• Venous: Drains to axillary, internal thoracic, and intercostal veins

• 75% drains to axillary nodes - mainly from lateral, upper outer, and central parts
  • Pectoral (anterior) nodes → central → apical
• Medial part drains to internal thoracic (parasternal) nodes
• Cross-drainage to opposite breast possible
• Inferior part drains to diaphragmatic, subdiaphragmatic nodes

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1. Capacitation of sperm in female reproductive tract
2. Acrosome reaction - release of acrosomal enzymes (hyaluronidase, acrosin) to penetrate corona radiata and zona pellucida
3. Penetration through zona pellucida via zona reaction
4. Fusion of sperm and oocyte cell membranes
5. Cortical reaction - prevents polyspermy (zona pellucida hardens)
6. Completion of meiosis II by secondary oocyte → mature ovum
7. Pronuclear fusion - male and female pronuclei fuse → zygote (2n = 46 chromosomes)

• Primary yolk sac (Heuser's membrane): Forms during week 2 from hypoblast cells lining blastocyst cavity
• Secondary yolk sac (definitive): Formed during week 3, lined by endoderm
• Functions: Blood cell formation (week 3-6), germ cell origin (primordial germ cells migrate from yolk sac wall), gut formation (part incorporated into embryo as primitive gut)
• Remnant forms Meckel's diverticulum if vitelline duct persists

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1. Perichondrium (except articular cartilage): Dense fibrous outer layer + inner chondrogenic layer
2. Chondrocytes: Cartilage cells in lacunae
   • Isogenous groups (cell nests) - daughter cells after mitosis
   • Surrounded by territorial matrix (basophilic, rich in proteoglycans)
3. Matrix (Extracellular matrix):
   • Type II collagen fibers (not visible with H&E - masked by ground substance)
   • Proteoglycans (aggrecan, chondroitin sulfate, keratan sulfate)
   • Hyaluronic acid
   • Interterritorial matrix (less basophilic)
4. No blood vessels, lymphatics, or nerves - avascular
5. Nutrition: By diffusion from perichondrium or synovial fluid

• Tunica intima: Endothelium + subendothelial connective tissue + internal elastic lamina
• Tunica media: 40-70 fenestrated elastic laminae, smooth muscle cells between laminae, type III collagen
• Tunica adventitia: Loose connective tissue, fibroblasts, vasa vasorum, nervi vasorum, external elastic lamina

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SECTION II - 50 Marks

Q4.

1. Temporal branch - supplies frontalis, orbicularis oculi (upper), corrugator
2. Zygomatic branch - supplies orbicularis oculi (lower), zygomaticus
3. Buccal branch - supplies buccinator, orbicularis oris, upper lip muscles
4. Marginal mandibular branch - supplies lower lip and chin muscles (depressor anguli oris, mentalis)
5. Cervical branch - supplies platysma

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1. Primary Motor Cortex (Area 4) - Precentral gyrus
   • Controls voluntary movements of contralateral side
   • Somatotopic organization = motor homunculus (inverted)
   • Largest representation: hand, face, tongue
2. Premotor Cortex (Area 6) - Anterior to area 4
   • Planning and programming complex movements
   • Involved in learning motor sequences
3. Supplementary Motor Area (Area 6, medial surface)
   • Bimanual coordination, speech initiation
4. Frontal Eye Field (Area 8)
   • Controls voluntary conjugate eye movements to opposite side
   • Lesion: Eyes deviate toward the side of lesion (away from paralysis in stroke)
5. Broca's Area (Areas 44, 45) - Inferior frontal gyrus (dominant hemisphere, usually left)
   • Motor speech area
   • Lesion: Broca's (expressive) aphasia - can understand but cannot speak fluently
6. Prefrontal Cortex (Areas 9, 10, 11, 12)
   • Personality, judgment, abstract reasoning, working memory
   • Lesion: Personality changes, disinhibition (frontal lobe syndrome)
7. Autonomic Centers: In orbitofrontal cortex

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Q5. (20 marks)

• Medially: Pituitary gland, sphenoid air sinus, internal carotid artery
• Laterally: Temporal lobe
• Superiorly: Optic chiasma, CN III
• Inferiorly: Foramen lacerum, foramen ovale
• Structures in lateral wall (from above downward): CN III, CN IV, CN V1 (ophthalmic), CN V2 (maxillary)
• Structures within the sinus cavity: Internal carotid artery (with sympathetic plexus), CN VI (abducens) - most medial and vulnerable

1. Superior ophthalmic vein
2. Inferior ophthalmic vein
3. Central vein of retina
4. Sphenoparietal sinus
5. Superficial middle cerebral vein
6. Inferior cerebral veins

1. To contralateral cavernous sinus via intercavernous sinuses (anterior and posterior) - forming circular sinus
2. Superiorly to superior petrosal sinus → transverse sinus
3. Inferiorly to inferior petrosal sinus → sigmoid sinus → internal jugular vein
4. To pterygoid plexus via emissary veins through foramen ovale and foramen lacerum
5. Anteriorly to ophthalmic veins → facial vein (danger triangle)

• Cavernous sinus thrombosis: Secondary to septic thrombophlebitis from "danger area of face" (upper lip, nose infections spread via facial vein → ophthalmic vein → cavernous sinus)
• Features: Proptosis, chemosis, ophthalmoplegia (CN III, IV, VI), orbital pain (CN V1), fever
• Carotid-cavernous fistula: Trauma ruptures ICA → pulsatile exophthalmos, orbital bruit
• Pituitary adenoma may compress the sinus

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• Semi-transparent, pearl-grey, ovoid membrane
• Lies at medial end of external acoustic meatus
• Obliquely placed (anteroinferiorly inclined at 55° to floor of meatus)
• Size: 1 cm x 0.85 cm

1. Pars tensa (larger, inferior) - taut; has three layers:
   • Outer (squamous epithelium)
   • Middle (fibrous - radial and circular fibers)
   • Inner (mucous membrane)
2. Pars flaccida (Shrapnell's membrane) - small, superior, above malleolar folds; only 2 layers (no middle fibrous layer)

• Handle of malleus - runs from center (umbo) upward and anteriorly
• Anterior and posterior malleolar folds
• Cone of light (light reflex) - anteroinferiorly from umbo (absent in middle ear effusion)
• Lateral process of malleus at upper end of handle

• Myringotomy - incision made in anteroinferior quadrant (safe quadrant) to drain middle ear effusion; avoids chorda tympani and ossicles
• Otitis media - red, bulging tympanic membrane; cone of light lost
• Perforation: Central perforation (safe, otitis media); marginal/attic perforation (unsafe - cholesteatoma)
• Otoscopy: visualized by pulling pinna upward and backward in adults

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Q6. Short Essay Questions (4 x 5 marks = 20 marks)

• 30% from primary motor cortex (area 4) - precentral gyrus
• 30% from premotor cortex (area 6)
• 40% from parietal lobe (areas 3, 1, 2)

1. Fibers converge in corona radiata
2. Pass through posterior limb of internal capsule (anterior 2/3)
3. Descend through middle 3/5 of cerebral peduncle (crus cerebri)
4. Pass through basis pontis (scattered)
5. Collect into pyramids of medulla oblongata
6. At medullomedullaropinal junction: 85-90% cross (pyramidal decussation) → lateral corticospinal tract (contralateral)
7. 10-15% remain uncrossed → anterior corticospinal tract (ipsilateral, cross at segmental level)

• Controls fine, skilled voluntary movements (especially of distal limb muscles)
• Corticobulbar fibers control facial, tongue, and pharyngeal muscles

• UMN lesion (above decussation): Contralateral spasticity, hyperreflexia, Babinski sign positive, no muscle wasting, loss of fine movements
• Internal capsule lesion (stroke): Contralateral hemiplegia
• LMN lesion (below anterior horn): Flaccid paralysis, hyporeflexia, atrophy, fasciculations
• Brown-Sequard syndrome: Ipsilateral UMN signs below lesion; contralateral pain/temperature loss

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• Pyramids (corticospinal fibers) - anterior median fissure separates them
• Arcuate nucleus - relay nucleus

• Posterior median sulcus
• Gracile nucleus (medial) and Cuneate nucleus (lateral) - nuclei of gracile and cuneate fasciculi
• Gracile and cuneate fasciculi (posterior funiculi)

• Sensory decussation (medial lemniscus decussation): Internal arcuate fibers from gracile and cuneate nuclei cross the midline, sweep anteriorly around central grey, and form the medial lemniscus
• Central canal - small, in center
• Reticular formation
• Spinal trigeminal nucleus and tract (lateral)
• Spinothalamic tract (anterolateral)
• Spinal accessory nucleus

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1. Corneal epithelium: Non-keratinized stratified squamous (5-6 layers), with basal columnar cells, wing cells, and surface squamous cells; rapid regeneration capacity
2. Bowman's membrane: Acellular, modified anterior stroma; type I collagen fibrils; does NOT regenerate after injury
3. Stroma (substantia propria): 90% of corneal thickness; parallel collagen lamellae (type I) interspersed with keratocytes (modified fibroblasts); regular arrangement gives transparency
4. Descemet's membrane: Thick basement membrane of endothelium; type IV collagen; regenerates after injury
5. Corneal endothelium: Single layer of flat polygonal cells; maintains corneal dehydration via Na+/K+ ATPase pumps; does NOT regenerate (fixed post-natal number)

• Cortex (3 layers from outside in):
  1. Molecular layer: Sparse cells - stellate cells, basket cells, dendrites of Purkinje cells, parallel fibers (axons of granule cells)
  2. Purkinje cell layer: Single row of large flask-shaped Purkinje cells - only output neurons of cortex; GABA-ergic (inhibitory); largest neurons
  3. Granular layer: Densely packed granule cells (most numerous neurons in brain); Golgi cells; glomeruli (synaptic complexes)
• Deep white matter: Climbing fibers (from inferior olivary nucleus), mossy fibers (from spinal cord, pons, etc.)
• Deep cerebellar nuclei (lateral to medial): Dentate, Emboliform, Globose, Fastigial

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1. Origin: Endodermal thickening in the floor of pharynx between tuberculum impar and copula (at foramen cecum), at the junction of anterior 2/3 and posterior 1/3 of tongue
2. Descent: Thyroid diverticulum descends through the tongue and neck as a bilobed structure connected to tongue by thyroglossal duct
3. Weeks 4-7: Migrates from foramen cecum downward and anteriorly in neck
4. Isthmus forms when two lobes are connected
5. Thyroglossal duct normally obliterates by week 7-8
6. C-cells (parafollicular cells) arise from neural crest (ultimobranchial body from 4th pharyngeal pouch)
7. Thyroid begins functioning around week 12

• Thyroglossal cyst: Persistence of thyroglossal duct - midline neck swelling moves upward on tongue protrusion
• Lingual thyroid: Failure of descent; thyroid remains at base of tongue
• Pyramidal lobe: Remnant of thyroglossal duct
• Accessory thyroid tissue along course of duct

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PAPER 2 (Lower Limb + Thorax + Abdomen, November 2023)

Q1. Short Answer Questions (10 x 1 mark = 10 marks)

1. Femoral artery
2. Femoral vein (posteromedial to artery)
3. Saphenous nerve
4. Nerve to vastus medialis
5. Descending genicular artery (terminal part of femoral artery)

• Its contraction pumps venous blood against gravity from lower limb back to heart
• The rich venous sinusoids within soleus are squeezed with each step, propelling blood upward in deep venous system
• Immobility (e.g., long flights) increases DVT risk in this muscle

1. Allows the lung to expand inferiorly and the root of lung to move downward during inspiration
2. Anchors the lower lobe of lung to the mediastinum
3. Contains some lymphatics

1. Tendon of obturator internus
2. Nerve to obturator internus
3. Pudendal nerve (re-enters pelvis)
4. Internal pudendal vessels (re-enter pelvis)

1. Giemsa banding (G-banding) - most widely used; produces dark and light bands unique to each chromosome
2. Quinacrine banding (Q-banding) - fluorescent staining; produces similar pattern to G-banding (Others: R-banding, C-banding, silver staining)

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Q2. (20 marks)

• Head of femur (ball) - spherical, 2/3 of sphere, covered with hyaline cartilage except fovea capitis
• Acetabulum of hip bone (socket) - formed by ilium, ischium, pubis at junction; deepened by acetabular labrum (fibrocartilaginous)
• Only lunate surface of acetabulum is articular (inverted horseshoe); acetabular fossa is filled with fat pad and ligamentum teres

1. Iliofemoral ligament (Y-ligament of Bigelow) - strongest ligament in body; triangular, anterior; from AIIS to intertrochanteric line; resists hyperextension
2. Pubofemoral ligament - inferior; from pubic part of acetabular rim to intertrochanteric line; resists abduction and extension
3. Ischiofemoral ligament - posterior; from ischial acetabular rim wrapping to neck; resists medial rotation and extension
4. Ligamentum teres (round ligament) - intracapsular; from fovea capitis to transverse acetabular ligament; carries artery to head of femur (branch of obturator artery - important in children)
5. Acetabular labrum - deepens socket
6. Transverse acetabular ligament - bridges acetabular notch

• Flexion (0-120°), Extension (0-30°), Abduction (0-45°), Adduction, Medial rotation, Lateral rotation, Circumduction
• Stability provided by deep socket, strong ligaments, and powerful muscles
• Hip flexors: iliopsoas (L1-L3); Extensors: gluteus maximus; Abductors: gluteus medius/minimus; Adductors: adductor group; Medial rotators: glutei; Lateral rotators: short external rotators

• Hip dislocation: Posterior most common (dashboard injury) - limb in flexion, adduction, medial rotation; risk to sciatic nerve
• Neck of femur fracture: Common in elderly osteoporotic females; subcapital fractures risk avascular necrosis of femoral head (blood supply disrupted)
• Trendelenburg sign: Gluteus medius weakness (superior gluteal nerve injury) - pelvis drops on opposite side when standing on affected leg
• Total hip replacement for severe OA

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• Superomedial: Semimembranosus, semitendinosus
• Superolateral: Biceps femoris
• Inferomedial: Medial head of gastrocnemius
• Inferolateral: Lateral head of gastrocnemius, plantaris
• Floor: Popliteal surface of femur, posterior capsule of knee joint, popliteus muscle
• Roof: Popliteal fascia (pierced by small saphenous vein)

• Plus: Popliteal lymph nodes, fat, small saphenous vein (entering), genicular branches

• Baker's cyst (popliteal bursitis) in posteromedial aspect
• Popliteal aneurysm - pulsatile mass
• Common peroneal nerve injury at fibular neck - foot drop

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• Posterior gluteal line and posterior surface of ilium
• Sacrum and coccyx (posterior surface)
• Sacrotuberous ligament
• Thoracolumbar fascia

• Upper 3/4: Iliotibial band (iliotibial tract)
• Lower 1/4: Gluteal tuberosity of femur

1. Powerful extensor of hip (most powerful) - from flexed position (e.g., climbing stairs, rising from sitting)
2. Lateral rotator of hip
3. Through ITB: extends and stabilizes knee (unlocking of knee)
4. Lower fibers: adduction
5. Antagonist to hip flexors

• Inferior gluteal nerve injury: difficulty climbing stairs, rising from chair, gluteal gait (lurching backward at each step)
• Gluteus maximus flap used in reconstructive surgery
• Intramuscular injections given in upper outer quadrant of gluteal region to avoid inferior gluteal nerve and superior gluteal nerve/artery

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Q3. Short Essay Questions (4 x 5 marks = 20 marks)

• Medial compartment of femoral sheath (contains lymphatics and fat - Cloquet's node)
• Femoral ring (inlet of femoral canal): Bounded by inguinal ligament (anteriorly), pectineal ligament (posteriorly), lacunar ligament (medially), femoral vein (laterally)

• The femoral ring is a potential weak point through which extraperitoneal fat can push the peritoneum into the femoral canal
• More common in females (wider pelvis, wider femoral ring relative to femoral sheath dimensions)
• Content: Extraperitoneal fat, peritoneal sac → may contain small bowel or omentum

• Down through femoral canal (below inguinal ligament)
• Exits saphenous opening
• Turns upward (because of superficial fascia - Scarpa's and Fascia lata) to appear above inguinal ligament - can be confused with inguinal hernia

• Narrow rigid femoral ring with unyielding boundaries (especially lacunar ligament medially)
• This is the most dangerous type of hernia - highest strangulation rate
• Treatment: Emergency surgical repair; lacunar ligament may need to be divided (watch for aberrant obturator artery - "corona mortis")

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• Floor (roof): Perineal membrane (inferior urogenital diaphragm fascia)
• Roof (ceiling): Scarpa's fascia equivalent in perineum = Colles' fascia
• Laterally: Closed by fusion of fasciae with ischiopubic rami and ischial tuberosities
• Opens posteriorly into potential space between Colles' fascia and Scarpa's fascia of anterior abdominal wall

1. Crura of penis (attached to ischiopubic rami) - covered by ischiocavernosus muscles
2. Bulb of penis - covered by bulbospongiosus muscle
3. Perineal body
4. Superficial transverse perineal muscles
5. Perineal branches of pudendal nerve and internal pudendal vessels
6. Spongy urethra (bulbar portion)

1. Crura of clitoris + ischiocavernosus
2. Bulbs of vestibule + bulbospongiosus
3. Greater vestibular glands (Bartholin's glands)
4. Superficial transverse perineal muscles

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1. Septum primum grows from roof of common atrium downward toward endocardial cushions; leaves a gap = ostium primum
2. Ostium primum closes as septum primum fuses with endocardial cushions
3. Before it closes, perforations appear in the upper part of septum primum → coalesce to form ostium secundum (maintains right-to-left shunt)

• Patent foramen ovale (PFO): Incomplete anatomical closure (25% of adults); usually asymptomatic; risk of paradoxical embolism and cryptogenic stroke
• Ostium secundum ASD: Defect in region of foramen ovale (most common ASD - 70%)
• Ostium primum ASD: Failure of fusion with endocardial cushions; associated with AV valve defects

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1. Haversian canal (central canal): Vertical, runs parallel to long axis; contains blood vessels (capillaries, postcapillary venules), lymphatics, unmyelinated nerves, loose connective tissue
2. Concentric lamellae: Rings of bone matrix arranged concentrically around Haversian canal
3. Lacunae: Spaces in lamellae containing osteocytes (mature bone cells)
4. Canaliculi: Tiny canals radiating from lacunae; contain processes of osteocytes that communicate via gap junctions - serve as nutrient pathways
5. Cement line: Outer boundary of each osteon; less mineralized; basophilic
6. Interstitial lamellae: Remnants of old Haversian systems between osteons
7. Circumferential lamellae: Inner (around marrow cavity) and outer (just deep to periosteum)
8. Volkmann's canals: Run obliquely/transversely; connect Haversian canals to each other and to periosteum and endosteum; contain blood vessels

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PAPER 3 (January 2024 - Upper Limb + Head & Neck)

Q4. Case Based Questions

1. Superficial fibular (peroneal) nerve - supplies fibularis longus and brevis; sensory to dorsum of foot and lower leg
2. Deep fibular (peroneal) nerve - supplies all dorsiflexors (tibialis anterior, extensor hallucis longus, extensor digitorum longus, fibularis tertius); sensory to 1st web space (between 1st and 2nd toes)

• Motor loss (foot drop - inability to dorsiflex): Deep fibular nerve supplies tibialis anterior (primary dorsiflexor), extensor hallucis longus and extensor digitorum longus. Paralysis of these muscles causes footdrop - the foot hangs in plantarflexion; patient uses high-stepping gait.
• Eversion loss: Fibularis (peroneus) longus and brevis are supplied by superficial fibular nerve; both are lost in common peroneal nerve injury.
• Sensory loss: Lateral/dorsal aspect of foot is supplied by superficial fibular nerve (dorsum except lateral border). The 1st web space (deep fibular) and lateral side of foot/little toe (sural nerve - not affected) are spared.
• The lateral side of little toe and 4th interdigital cleft are spared because the sural nerve (from tibial nerve) supplies these areas and is NOT part of the common peroneal distribution.

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• In portal hypertension (cirrhosis, Budd-Chiari), blood is diverted through these anastomoses
• Esophageal varices: Ruptured varices = life-threatening upper GI bleed; managed with endoscopic banding, sclerotherapy, TIPS
• Splenomegaly accompanies portal hypertension
• Ascites from portal hypertension + hypoalbuminemia

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Q5. (20 marks)

• J-shaped muscular organ; most dilatable part of GI tract
• Parts: Cardia, fundus (above cardiac orifice level), body, pyloric antrum, pyloric canal, pylorus
• Surfaces: Anterior and posterior
• Curvatures: Greater curvature (left/inferolateral, longer), lesser curvature (right, shorter)
• Cardiac orifice: Left of T10-11 vertebra
• Pyloric orifice: Right of L1 vertebra at transpyloric plane; pyloric sphincter palpable
• Incisura angularis: notch on lesser curvature

• Anterior: Anterior abdominal wall, left lobe of liver, diaphragm
• Posterior (stomach bed): Pancreas, transverse mesocolon, left kidney/adrenal gland, spleen, splenic artery, diaphragm
• Left: Spleen, splenic vessels
• Right: Liver, lesser omentum

• Lesser curvature: Left gastric artery (celiac axis branch) + right gastric artery (hepatic artery branch) - anastomose along lesser curvature
• Greater curvature: Left gastroepiploic artery (splenic artery) + right gastroepiploic artery (gastroduodenal artery) - anastomose along greater curvature
• Fundus: Short gastric arteries (5-7 branches from splenic artery)
• Venous drainage: Left gastric → portal vein; right gastric → portal vein; right gastroepiploic → superior mesenteric; left gastroepiploic + short gastric → splenic vein

• Gastric ulcer: Most common on lesser curvature near incisura angularis; erodes left gastric artery posteriorly
• Duodenal ulcer: Posterior wall erosion bleeds from gastroduodenal artery
• Gastrectomy: Billroth I (gastroduodenostomy), Billroth II (gastrojejunostomy)
• Pyloric stenosis: Projectile non-bilious vomiting in male infants; palpable "olive" mass
• Gastric carcinoma: Most common at pyloric antrum; spreads to supraclavicular nodes (Virchow/Troisier's node), peritoneally, liver

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• Anterior: Free edge of lesser omentum (portal vein, hepatic artery, bile duct)
• Posterior: IVC
• Superior: Caudate lobe of liver
• Inferior: First part of duodenum

• Anterior: Posterior surface of lesser omentum and stomach
• Posterior: Pancreas, transverse mesocolon, diaphragm (peritoneum on these structures)
• Superior: Caudate lobe of liver
• Inferior: Greater omentum (fused layers)
• Left: Gastrosplenic ligament, lienorenal ligament
• Right: Epiploic foramen

1. Superior recess - behind liver (caudate lobe), near esophagus
2. Inferior recess - projects between layers of greater omentum
3. Splenic recess - extends to left toward hilum of spleen

• Acute pancreatitis: Enzymes released into lesser sac → pseudocyst formation; Gray-Turner's sign (flank bruising via lienorenal ligament)
• Penetrating duodenal ulcer: Bleeds/perforates into lesser sac
• Fluid drainage: Accessed surgically via epiploic foramen

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• Anterior: Aponeurosis → linea alba (midline)
• Inferior: Anterior half of outer lip of iliac crest
• Medial/inferior edge of aponeurosis folds back on itself to form inguinal ligament (Poupart's ligament) - from ASIS to pubic tubercle

1. Inguinal ligament: Inferior folded edge; spans ASIS to pubic tubercle; floor of inguinal canal
2. Lacunar ligament (Gimbernat's ligament): Triangular medial expansion of inguinal ligament attached to pectineal line; forms medial boundary of femoral ring
3. Pectineal ligament (Cooper's ligament): Extension of lacunar ligament along pectineal line
4. Superficial inguinal ring: Triangular gap in aponeurosis superolateral to pubic tubercle; transmits spermatic cord/round ligament
5. Reflected inguinal ligament: From superficial ring margin to linea alba
6. Conjoint tendon (inguinal falx): Fusion of internal oblique + transversus aponeurosis behind superficial ring; strengthens posterior wall of inguinal canal medially

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Q6. Short Essay Questions (4 x 5 marks = 20 marks)

• Superior: Thoracic inlet (superior thoracic aperture) - manubrium, 1st rib, T1 vertebra
• Inferior: Horizontal plane at sternal angle (angle of Louis) at T4/T5 intervertebral disc level - separates from inferior mediastinum
• Anterior: Manubrium sterni
• Posterior: T1-T4 vertebral bodies
• Lateral: Mediastinal pleura

1. Thymus (or its remnant)
2. Great vessels: Arch of aorta, brachiocephalic trunk (right), left common carotid artery, left subclavian artery; superior vena cava (SVC) formation from brachiocephalic veins
3. Trachea (bifurcates at lower border into 2 bronchi at T4/5)
4. Esophagus and thoracic duct (upper part)
5. Phrenic nerves (bilateral)
6. Vagus nerves (bilateral); left recurrent laryngeal nerve loops under arch of aorta
7. Cardiac plexus (superficial part)
8. Lymph nodes: Paratracheal, tracheobronchial (inferior - carina)

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1. Rami communicantes (grey and white) to sympathetic chain
2. Collateral branch - runs along inferior border of space (supplies intercostal muscles)
3. Lateral cutaneous branch - pierces at mid-axillary line; divides into anterior and posterior branches - supplies skin of thorax/abdomen
4. Anterior cutaneous branch - pierces anterior thoracic wall near sternum; divides into medial and lateral branches - supplies midline skin
5. Muscular branches: To intercostal muscles (internal, external, innermost), subcostalis, transversus thoracis
6. Pleural and peritoneal branches (sensory)

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• Ultrasound-guided needle insertion through anterior abdominal wall, uterine wall, and amniotic membrane
• 15-20 mL amniotic fluid aspirated

• Fetal cells (amniocytes shed from skin, GI, respiratory tracts)
• Amniotic fluid itself for biochemical analysis

1. Chromosomal analysis (karyotyping, FISH) - Down syndrome (trisomy 21), Edwards (trisomy 18), Patau (trisomy 13), sex chromosome anomalies
2. Biochemical: Alpha-fetoprotein (AFP) elevated in neural tube defects (anencephaly, spina bifida); acetylcholinesterase
3. Molecular genetics: Single gene disorders (cystic fibrosis, sickle cell disease)
4. Fetal lung maturity: Lecithin/sphingomyelin ratio >2:1 = mature lungs
5. Infection detection: CMV, toxoplasma

• Miscarriage risk: ~0.5-1%
• Infection (chorioamnionitis)
• Fetal injury
• Amniotic fluid leakage
• Rh-isoimmunization (give anti-D to Rh-negative mothers)

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Note: Pages 7-32 of the PDF could not be fully extracted due to processing limits, but the above covers all the questions visible in pages 1-6 (two complete exam papers - General Anatomy/Upper Limb and the Lower Limb/Thorax paper). All answers are calibrated to the mark allocations specified.