Dr Sreeja S MD(Hom)
Study of the microscopic structure of the human organism co related with the development, function and clinical significance. It is derived from Greek term” anatome” meaning cutting apart.
EMBRYOLOGY It is the study of the formation and development of the embryo from the moment of its inception upto the time when it is born as an infant.
Gonads: no: of chromosomes in an organism=23 pairs/46 no.
♂—–44 autosomes –XY
♀—-44 autosomes – XX
- Karyotyping : Classification of chromosomes based upon their differences that enable us to identify each chromosome individually.
- Spermatogenisis : The process of formation and development of spermatazoan .
- Formed in the wall of the seminiferous tubules of testes.
- Spermiogenesis (spermateleosis) : The process of transformation of a circular spermatid to a spermatozoan.
- Mature spermatozoan: Has a head, a neck middle piece and a principal piece or tail. Head is covered with a cap called acrosome.
- Length -50-60 microns
- Golgi apparatus forms the acrosomic cap.
- Nucleus forms head.
- Mitochondrion forms the sheath of middle piece.
- Proximal centriole comes to lie in the neck.
- Distal centriole becomes ring shaped and forms the annulus.
- Axial filament grows out from the centriole and is present in middle piece and tail.
- Viability of spermatozoa =4 days.
Ovulation: The shedding of ovum from the ovary.
Corpus luteum- It is an important structure derived after the rupture of ovarian follicle to shed the ovum.
It secretes hormone progesterone.
Viability of ovum =24 hrs
Menstrual cycle: Divided into 4 phases
1.Post menstrual phase
Follicular phase —post menstrual + proliferate phase -~ Oestrogen
Luteal phase – secretory +menstrual phase -~ progesterone
Size of Oocyte— 120u.
- Approximate number of occytes at puberty—around 40,000.
- Approximate number of ova liberated during reproductive period of female—around 300 to 400.
- Time required for formation of spermatozoa from spermatogonium—64 days.
- Fertilized ovum reaches uterine cavity—by 4 days.
- Implantation of ovum (fertilized) occurs—about 7th day.
- Primitive uteroplacental circulation begins—by end of 2nd week.
- Number of somites in embryo — 42 to 44.
- Time of somite formation — 21 to 30th day.
- Organogenesis — from 4th to 8th weeks.
- Formation of primary ovary in a female takes place by 8th week
Differentiation of genital organs
1.Persons with two X chromosomes are female; those with one x and one y are male.
2.Y chromosome bears a gene responsible for production of a testis determining factor.
3.Interstitial cells in testis produce testosterone .It forms a complex with certain receptor proteins which attaches itself to DNA. This causes the mesonephric duct to develop as in male.
4.Presence of dihydrotestosterone .
5.Sertoli cells produce mullerian inhibiting substance .This causes regression of paramesonephric ducts.
Genital swellings in male differentiate into scrotum whereas in a female, they form labia majora.
The mesonephric duct in a female develops into Gartner’s duct.
The Mullerian ducts in male develop into appendix testes whereas in a female, they develop into uterus and uterine tubes.
In female, the homologue of prostatic glands are paraurethral glands.
Differs from adult circulation in
a) Source of oxygenated blood is not the lung but the placenta.
b) Oxygenated blood from placenta comes to foetus through umbilical vein and joins the left branch of portal vein. Small portion passes through the substance of the liver to I V, but the greater part passes direct to I V through the ductus venosus.
Changes at birth: 1) umbilical artery contracts.
2) Lumen of umbilical veins and ductus venosus occludes and this takes place a few minutes after birth.
3) Ductus arteriosus occludes by about 10 th day.
4) Pulmonary vessels increase in size.left atrial pressure rises than that of right atrium and leads to closure of foramen ovale.
- Umbilical artery – medial umbilical ligament
- Left umbilical vein – ligament teres of the liver
- Ductus venosus – Ligamentum venosum
- Ductus arteriosus – Ligamentum arteriosum
OSTEOLOGY : Study of bones.
Bones are divided according to their
Human skeleton ——-axial} bones of skull, vertebral column, ribs, sternum, hyoid.
——-appendicular} bones of pectoral, pelvic girdle ,upper and lower limbs
- Long bones: eg: Femur, tibia, humerus, ulna, radius, and fibula
- Short long bones: eg: Metacarpals, metatarsals, phalanges
- Short bones: eg: Carpals, tarsals
- Flat bones: eg : Scapula , sternum, ribs, parietal and frontal.
- Pneumatic bones : Maxillary ,sphenoid , ethmoid, mastoid part of temporal bone.
- Irregular bones: eg: Vertebrae, skull bones
- Sesamoid bone: eg: patella, pisciform, fabella
- Compact bone =consisting of haversian system
- Cancellous (spongy) bone = consisting of irregularly placed lamellae.
- Diploic =consisting of inner and outer tables of compact bone with intervening porous layer.
- Ecto chondral bones: which develop in membrane (membranous)
- Endochondral bones: which develop in cartilage. (cartilageneous)
Total no of bones —206
- Upper limbs-64
- Lower limbs-62
- Skull – 29(14-facial bones
- – 14- cranial bones , hyoid bone )
- Ribs- 12 pairs
- Longest bone—femur
- Smallest bone—stapes
- Strongest part in human body- Enamel of teeth
- Largest sesamoid bone — Patella developing in quadriceps.
- Microscopic unit of a bone: Haversian system (secondary osteone)
Process of gradual bone formation.
a)Ossification in membrane (direct)—easy process
Eg: clavicle, bones of face,vault of skull.
b)Ossification in cartilage (Indirect) —gradual process.
Eg: bones of limbs, trunk.
- Secondary cartilage bone: eg: neck of mandible, sternal end of clavicle.
- Primary centres of ossification may be single or multiple ,appear before birth between 6th – 8th week of foetal life except cuneiform ,navicular bones .
- Secondary centres of ossification are multiple and appear after birth except lower end of femur.
- Ossification of acetabulum is complete at 16-17 years
- Growing ends of bones of upper limb—upper end of humerus & Lower end of radius and ulna
- Growing ends of bones of lower limbs —- lower end of femur & Upper limbs of tibia and fibula
- In long bones, growing ends fuse with shaft at 20 yrs and opposite ends at about 18 yrs.
- In other bones it is between 20-25 yrs.
Types of epiphysis are :
a) Pressure epiphyses – located at pressure points like joints
b) Traction epiphyses: subjected to traction by pull of muscles when located at the muscular attachment
c) Atavistic epiphyses: centre appearing in the part of bone which was orginally a separate bone in evolution eg : Coracoid process of scapula.
Hyaline cartilage has a tendency to get calcified in later years of life.
Skull bones—22 bones
- Facial bones (14)-paired-nasal, maxillae, zygomatic, palantine, lachrymal, inferior nasal connchae.
- Unpaired-mandible, vomer
- Cranial bones (14)-paired- parietal, temporal, ear ossicles
- Unpaired- frontal, ethmoid, sphenoid, occipital.
Carpal bones- 8 bones Lat TO medial (Proximal) Scaphoid, lunate, triquetral, pisiform
- (Distal)—Trapezium, trapezoid, capitate, hamate.
- Tarsal bones-7 bones (proximal) Talus, calcaneus
- (distal) medial cuneiform, intermediate cuneiform, lateral cuneiform, cuboid.
- Largest and strongest of tarsal bones—Calcaneus
Paranasal sinuses 4 pairs : Frontal, sphenoidal, ethmoidal, maxillary.
Largest of all air sinuses —Maxillary sinus (Antrum of Highmore)
Foramina of skull
Anterior cranial fossa :
1.Foramen caecum: lies between the alae of crista galli of ethmoid and frontal crest. Transmits an emissary vein.
Middle cranial fossa:
2.Optic canal (foramen): Transmits optic nerve, opthalmic artery.
3.Superior orbital fissure: Bounded by lesser wing above, greater wing below and body of sphenoid medially.
Divided by three compartments by common tendinous ring.
Transmits –superior and inferior divisions of oculomotor, nasociliary nerve, abducent nerve, trochlear nerve, frontal nerve, lacrimal nerve, lachrimal artery, orbital branch of middle meningeal artery, superior ophthalmic vein,recurrent meningeal branch of lachrymal artery, inferior ophthalmic vein.
- Foramen rotundum—transmits maxillary nerve.
- Foramen ovale — transmits mandibular nerve,accessory meningeal artery ,lesser superficial petrosal nerve, emissary vein.
- Foramen spinosum— transmits middle meningeal artery, nervus spinosus
- Foramen lacerum— transmits Internal carotid artery.
- Carotid canal—- transmits internal carotid artery with plexus, emissary veins, meningeal lymphatics.
Posterior cranial fossa:
- Jugular foramen — transmits 9th,, 10, 11th cranial nerves.
- Foramen magnum—largest foramen in skull.
Divided into anterior small compartment: Apical ligament
Upper band of cruciate ligament
Condylar parts on sides.
Posterior large compartment: lower end of medulla oblongata, 2 anterior and one posterior spinal artery, veins joining venous plexus, lower part of tonsil of cerebellum, vertebral artery, sympathetic plexus, spinal root of accessory nerve.
Ribs: 12 in number on each side.
- True ribs—1-7th
- False ribs— 8-12th
- Floating ribs — 11-12th
- Atypical ribs—1, 2, and 10.11, 12th.
Folds of duramater
- Falx cerebri – encloses superior sagittal sinus, inferior sagittal sinus, straight sinus
- Tentorium cerebelli- encloses transverse sinuses, posterior petrosal sinuses.
- Falx cerebelli—encloses occipital sinus
- Diaphragma sellae—encloses anterior and posterior intercavernous sinuses.
Important points in skull
- Bregma: meeting of coronal and sagittal sutures.site of anterior fontanelle, closes at 11/2 yrs of age.
- Lambda: meeting of sagittal and lambdoid sutures .site of posterior fontanelle ,closes at 2-3 months of age.
- Nasion : meeting point of internasal and fronto nasal sutures.
- Inion : centre of external occipital protruberance.
- Pterion : area formed by meeting of frontal, squamous part of temporal ,parietal, greater wing of sphenoid.deep to this lies anterior branch of middle meningeal artery, middle meningeal vein ,stem of the lateral sulcus.
- Asterion : point at the postero inferior angle of parietal bones.
- Inferior aperture (outlet )of thorax.
- Aortic opening—T12- transmits Aorta, thoracic duct, Azygos vein
- Oesophageal opening—T10-transmits oesophagus, gastric nerves, oesophageal branches of left gastic artery.
- Venecaval opening — T8 transmits inferior venecava, branches of right phrenic nerve.
CEREBROSPINAL FLUID (CSF)
Definition CSF is a modified tissue fluid in the central nervous system. It is contained in the ventricular system of brain and the subarad space of brain and spinal cord. CSF replaces lymph in the CNS. It acts as a sensitive mirror which reflects diseases of the na system. Formation
1.The bulk of the CSF is formed by choroid plexuses of the lateral ventricules, and the lesser amounts by the choroid plexus the third and fourth ventricles. ‘
2.Possibly it is also formed by the capillaries on the surface of the brain and spinal cord.
Circulation CSF passes from the lateral ventricles to the third ventricle through foramina of Monro (interventricular foramina). Fron ventricle it passes to the fourth ventricle through cerebral aqueduct. From fourth ventricle the CSF passes to the subarachnoid around the brain and spinal cord through the foramen of Magendie and foramina of Luschka.
1.CSF is absorbed chiefly by the arachnoid villi and granulations, and is thus drained to the cranial venous sinuses. 2.It is also absorbed partly by the perineural lymphatics around I, II, VII and VIII cranial nerves 3.And also by the veins related to the spinal nerves.
Rate of Formation 200 cc/hour, 5000 cc/day. Total Quantity About 150 cc. Pressure:60-150 mm of fluid (or water). Composition Proteins 20-40 mg per 100 cc. Sugar 50-75 mg per 100 cc. Chlorides 720-750 mg per 100 cc. Cells 0-5 per cubic mm
Functions : It is (a) protective, (b) nutritive, and (c) excretory to the CNS.
Applied Anatomy 1.CSF can be obtained by (a) lumbar puncture, (b) cisternal puncture, or (e) ventricular puncture. Lumbar puncture is 1st method of all and is commonly used. It is done in the interspace between third and fourth lumbar spines.
2.Biochemical analysis of the CSF is of diagnostic value, as the cases of meningitis and spinal tumours.
3.Drainage of CSF at regular intervals is of therapeutic value in meningitis. Certain intractable headaches of unknown are also known having been caused by a mere lumbar puncture with drainage of CSF.
4.Obstruction to the flow of CSF in the ventricular system of brain leads to hydrocephalus in children .Spinal obstruction leads to Froins syndrome.
- Length of parotid duct: 5 cm.
- Length of submandibular duct: 5 cm.
- Length of auditory tube: 36 mm.
- Bony part: 12 mm.
- Cartilagenous part: 24 mm
- Length of external acoustic meatus(from bottom of choncha): 2.4 cm.
- Bony part:16 mm.
- Cartilagenous part:8 mm.
- Transverse diameter of mid cavity
- Opposite the centre of tympanic membrane: 2 mm.
- Total number of cones in the retina: 6.3 to 6.8 million.
- Length of pharynx: 12 to 14 cm
- Length of larynx
- Length of vocal cords
- Length of Trachea –
- Pituitary gland: 13 x 8 mm.
- Heart — Measures 12 x 9 cm (5×3 or 3.5 inches)
- Weight 300 g (males)
- 250 g (females)
- Termination of oesophagus 11th Thoracic vertebra.
Constrictions in oesophagus :
- at commencement 15 cm from incisor teeth.
- at crossing over by aortic arch 22.5 cm from incisor teeth.
- at crossing over by left principal bronchus 27.5 cm from incisor teeth.
- at its point of piercing diaphragm 40 cm from incisor teeth.
- Cardiac orifice — Behind left 7th costal cartilage 1″ from its junction with sternum.
- Pyloric orifice — 1.2 cm (0.5″) to the right of midline on transpyloric plane.
- Capacity — at birth 30 ml; adults 1500 ml.
Length of small intestine: 6 to7 metres
Length of duodenum: 10” or 25 cm
- 1 st part: 5 cm
- 2nd part: 7.5 cm
- 3rd part: 10 cm
- 4th part: 2.5 cm
Length of large gut: 1.5 metres
Hilum of kidney — Transpyloric plane (LI).
Kidney:Length: 11 cm, Breadth : 6 cm, Antero-posterior diameter: 3 cm
- Length of Ureter : 25 cm
- Length of male urethra: 18-20 cm
- Spermatic cord : 9-10 cm
- Length of inguinal canal: 4 cm
- Testis: Length-4.5 cm, Breadth-2.5cm, Anteroposterior dr-3
- Ovary: Length -3 cm, Width-1.5 cm,Thickness-1 cm
- Uterus: Length-7.5 cm, Breadth-5 cm,Antero-posterior diameter-2.5 cm
- Weight :30 to 40 gms
- Uterine tubes: Length-10 cm
- Saphenous opening — Height 1.5 to 8 cm; Width 1 to 3 cm
- Femoral sheath — Length 3 to 4 cm.
- Femoral canal — Length 1.25 cm.
- Tendo calcaneus — Length 15 cm.
- Weight of spinal cord — 30 gms.
- Length of spinal cord — 45 cm.
- Filum terminale — 20 cm.
- Internum —15 cm.
- Externum — 5 cm.
- Commencement of spinal cord — Cranial border of C1 vertebra (Atlas).
- Termination of spinal cord -— lower border of LI or disc between LI & L2 vertebrae.
- Cervical enlargement of spinal cord — Circumference 39 mm. Extends from LI to SI spinal segments.
- Lumbar enlargement of spinal cord — Circumference 35 mm. Extends from LI to S3 spinal segments.
Vertebral levels of spinal segments
- Cervical vertebral spine corresponds to succeeding cord segment Eg : C6 spine to C7 segment.
- Upper thoracic spine corresponds to two spinal segments lower Eg : T4 spine corresponds to T4 spinal segments.
- Lower thoracic spine corresponds to three spinal sements below Eg : T10 spine to LI spinal segment. T11 spine to L3segment, T12 spine to SI segment.
- New born child lower limit of spinal cord is at — L3 vertebral upper border.
- Length of medulla oblongata — 3 cm.
- Shortest segment of brain stem — mid brain 2.cm.
- Thalamus-Length —- 4 cm.
- Corpus callosum length 10 cm.
- Specific gravity of C.S.F: 1007.
- Pressure of CSF (in recumbent position):100 to 150 mm of H2O
- Total volume of CSF in man: 140 ml; amount of CSF in Ventricles 25 ml.
- Commencement of subclavian artery — Behind sternoclavicular joint.
- Termination of Subclavian artery — Outer border of 1st rib.
- Termination of Brachial artery — Neck of radius.
- Thoracic Aorta :
- Commencement — T4 Vertebral lower border.
- Termination — T12 Vertebral body.
- Abdominal Aorta commencement — T12 Vertebral body.
- Coeliac Trunk:Origin — T12, Length —1.25 cm.Superior mesenteric artery — LI.
- Inferior mesenteric artery —L3.
- Commencement of common iliac —L4 vertebral body.
- Bifurcation of common iliac—Sacroiliac joint
- External iliac termination —Mid-inguinal point.
- Vertebral prominence — C7.
- Superior angle of scapula —T2.
- Upper border of manubrium sterni (suprasternal notch)—T2, T3 vertebral junction.
- Spine of scapula —T3
- Sternal angle —T4 & T5 (Disc between).
- Inferior angle of scapula — T7.
- Xiphisternal joint — T9.
- Tonsil is derived from 2nd pouch
- CSF to plasma glucose ratio is normally 0.6 to 0.8
- Appearance of permanent kidney — 5th week of Intrauterine period.
- Invasion of primordial germ cells into developing gonad — 5th week.
- Appearance of neural plate (nervous system) — 3rd week.
- Development of eye — between 4th and 7th weeks.
- Appearance of limb buds — beginning of 5th week.
Descent of testis:
- At deep inguinal ring— 7th month of intra uterine life.
- In inguinal canal — 8th month of intrauterine life.
- At superficial inguinal ring — 9th month of intrauterine life.
- Haller’s circle is found in the Pyloric orifice.
- Marginal artery of Sudeck lies at 2.5-3.8 cm from colon.
- Portal vein is about 8 cm long.
- The maximum breadth of mesentry is in central part and is 8 inches
- The lesser omentum is a fold of peritoneum extending from lesser curvature of stomach and first 2 cm of duodenum to the liver.
- Common carotid artery is derived from III aortic arch.
- At full term, diameter of placenta is 6-8 inches.
- Mesentry contains about 100-200 lymph nodes.
- Between lowest sigmoid and sup. Rectal artery anastomosis is regarded as the critical point of Sudeck.
- Mesentry is fan shaped fold of peritoneum.
- Total area of placenta is 14 sq. m.
- Oesophagus structure is related to both left and right lung.
- Weight of parathyroid gland is 50 mg.
- Length of caecum is 6 cm.
- Sprain of ankle is most often due to abduction.
- The superficial muscles of the back of leg are supplied by S1,2.
- Thickness of suprarenal is 10 mm.
- Duodenojejunal is largest duodenal recess.
- Cisterna chyli is 5-7 cm long.
- Ovary has minimum thickness.
- V pharyngeal arch disappears at the earliest.
- Weight of prostate gland is 8 gm.
- Longest part of duodenum is III.
- Left dome of diaphragm corresponds to the lowest part of 5 rib.
- Width of stomach is 10-12 cm.
- Claustrum is situated between putamen and Insula.
- Third ventricles are derived from Diencephalon.
- Thickness of spleen is 3-4 cm.
- Middle one third of transverse colon is derived from midgut.
- Placental membrane at its formation is 0.025 mm thick.
- Syncytiotrophoblast is called plasmoditrophoplast.
- Midbrain is Mesencephalon.
- The left brachiocephalic vein is about 7.5 cm long.
- Deep palmar arch is about 4 cm long.
- Spine of scapula corresponds to 3rd thoracic spine.
- Pereoneal tubercle if felt as a prominence about 2.0 cm below tip of lateral malleolus.
- Hip joint lies 1.2 cm vertically below the middle third of inguinal ligament.
- Pulmonary arteries are derived from VI aortic arch.
- Ischial tuberosity is felt 5.0 cm away from the median plane.
- Nelaton’s line touches the centre of acetabulum, ishcial tube andAnt.sup. iliac spine.
- Filum terminale is about 20 cm long which extends from conus medullaris to the back of the 1st coccygeal vertebral segment
- The duramater of spinal cord ends at S2 vertebral level.
- Erb’s point is C4 C5.
- Ureter is 50 cm long.
- Distance between upper incisors and gastroesophageal junction is 40 cm.
- The ratio of weight of liver and weight in an adult is1: 40.
- Oesophagus crosses the diaphragm at level of T10.
- Developing gonad is identified as male or female by the end of 7th week.
- The infant with pupillary membrane must have been product of pregnancy lasting less than 7 months.
- Stillborn foetus with eyelids fused is of 3-7 months.
- Length of a mature human spermatozoon is 50-60 microns.
- Breast development in intrauterine life starts at 12 weeks.
- Point situated 1 cm below sacral promontary representing CG of body is Weber’s point.
- The number of ossification centres in the hyoid bone is 6.
- Great saphenous vein is exposed anterior to medial malleolus at 2.5 cm.
- Ossification centres for all carpal bones is found by 5th year.
- Xiphisternal junction is usually at the level of disc between T9 and T10 verterbra.
- Length of ductus deferens is usually 45 cms.
- Frontal eye field motor area is 8.
- Nerve supplying submandibular gland is VII nerve.
- Length of female urethra is 4 cm.
- Root value of phrenic nerve is C^5.
- Sacral canal’s volume is 25-35 c.c.
- Detrusor is supplied by Sj_4.
- At midaxillary line, parietal pleura extend up to level of 10th rib.
- The weight of the left healthy lung is 570 gm and that of right is 620 gm.
- The SA node is by a branch of the right coronary artery in 65%.
- The AV node is supplied by a branch of the right coronary artery in 80%.
- Upto 80% of liver resection can be tolerated by noncirrhotic individual.
- Liver has a high power of regeneration. Following resection of two third portion of liver, it regenerates in about six month
- Hepatocytes drain about one litre of bile daily into bile canaliculi.
- Common bile duct (CBD) is about 10 cm long.
- Normal size of CBD is 6-10 mm.
- Normal pressure in portal vein is 6-12 mm. of Hg.
- Average size of spleen is about 5x3x1 inch. Average weight is about 150 gm.
- Average size of kidney is been shaped, having weight about 150 gm.
- Blood flow through each Kidney is 1-2 litre per minute.
- Normal capacity of UB is about 250 ml. but can accommodate upto 500 ml of Urine.
- Prostate secretes 0.5-2 ml of fluid per day, which contains Acid Phosphatase, Prostate glandins, Fibrinogen and Citric Acid.
- Length of large intestine is’1.5 m.
- Length of anal canal is 3.8 cm.
- Part of anal canal about 15 mm below anal valves is the transitional zone pectin.
- Bile duct is 7.5-10 cm long.
- Gall bladder has Capacity of 45 ml (range 30 to 50 ml) and length of 7.5 to 10 cm.
- Ureter lies 2 cm lateral to cervix and Uterine artery crosses above and infront of ureter.
- Size of ovary is Length 3 cm, Width 1.5 cm, Thickness 1 cm.
- Vascular segments of kidney are 5.
- Number of lobules in foetal kidney is 12.
- Saphenous opening is a gap in fascia lata of thigh, situated 4 cm. below and lateral to pubic tubercle. Its sharp edge is called falciform margin.
- Saphenous opening is covered by cribriform fascia.
- Inter alveolar septum—0.2 m thick (Arithmetic means thickness of barrier in human is 2.2 nun).
- Manubriosternal angle may be ossified after the age of 30 years.
- Cervical curve appears in intrauterine life and accentuaies by 3 or 4 months when the child hold up the head.
- Lumbar curve appears at 12 to 18 months when the child begins to walk.
- Subpubic arch is more angular in males (50° to 60°), in females it is wide usualy 80° to 85°.
- Greater sciatic notch is wider in females — 50.4° and in males is — 74.4°.
- Sacral index in males 10.5% and in females 115%.
- In hip joint, extension beyond vertical is 10° to 20°.
- Extension of knee beyond vertical femoro-tibial axis is 5° -10° and flexion is 120° with extended hip joint.
- Passive rotation in knee is about 60° to 70° but conjuct rotation is only about 20°.
- In “Colles “fracture”, there is a fracture of distal end of radius with displacement of lower fragment backwards and upward. This occurs due to fall of outstretched hand. Resulting deformity is dinner fork deformity.
- Anal canal is 38 mm long (upper – 15 mm, middle – 15 mm, lower – 8 mm)
- In hip, primary centres of ossification appear in the order of ilium (2nd month), ischium (4th month), and pubis .
- Main action of quadrator femoris is lateral rotation.
- Foramen lacerum lies in between petrous part of temporal bone and sphenoid.
- Parotid duct pierces the buccinator muscle.
- Functional tissue of lungs is alveoli.
- Carpal tunnel syndrom involves median nerve
- Meckel’s diverticulum arises from the antimesenteric border of ileum.
- Auerback’s plexus is located in oesophagus.
- Brachialis is supplied by musculocutaneous as well as radial nerve.
- Gluteus maximus is supplied by inferior gluteal nerve.
- Trendelenburg sign may be positive in gluteal medius paralysis.
- Elbow is a condyloid joint
- Left testicular vein drains into left renal vein.
- Flexor digitorum profundus has a dual nerve supply.
- Anterior interosseus artery is a branch of ulnar artery.
- Purkinje cells in cerebellum are input cells.
- The most fixed part of the GIT is duodenum.
- The glands of Brunner are seen in duodenum.
- Spinal part of accessory nerve supplies sternocleidomastoid muscle.
- T-s free border of lesser omentum contains hepatic artery, portal vein and bile duct.
- Lateral rectus is supplied by VI cranial nerve.
- Dentate nucleus is a part of cerebellum.
- Lamina cribrosa is modification of sclera.
- Automatic bladder is seen in lesions of higher centres whereas lesions at lower centres lead to autonomic bladder.
- Coronary sulcus is occupied by the coronary sinus.
- Siren or vena cava is formed by brachiocephalic veins.
- The base of heart, formed by atria, lies opposite the 5th-9th thoracic vertebrae.
- All the tongue muscles are supplied by hypoglossal nerve except palatoglossus muscle which is supplied by pharyngeal plexus of nerves
- Tympanic membrane is derived from ecto, meso and entoderm.
- Edochondral ossification is seen in scapula.
- Melanoblasts are derived from neural crest cells.
- ﻨHuman placenta is haemochorial.
- ﻨCommonest part of aorta ruptured in trauma is junction of thoracic and abdominal aorta.
- ﻨThe only pharyngeal muscle innervated by the glossopharyngeal nerve is stylopharyngeus.
- Radial bursa encloses the tendon of flexor pollicis longus.
- ﻨChoroid fissure of the eye permits the entry of hyaloid artery.
- ﻨUncinate fasciculus connects frontal and temporal lobes.
- ﻨMusician’s nerve is ulnar nerve.
- Ligament of Cooper is related to breast.
- ﻨJacobson’s nerve is a branch of IX nerve.
- Fascia cribrosa is related to femoral canal.
- ﻨBoa’s point is a tender spot felt in the left of T12 in a patient with gastric ulcer.
- Buck’s fascia is related to penis.
- Prostoperitoneal fascia is Denonviller’s fascia.
- ﻨFascial extension of lacunar ligament along iliopectineal line is Cooper’s ligament.
- ﻨAlderman’s nerve is a branch of X nerve.
- ﻨLabourer’s nerve is median nerve.
- Veins communicating the cavernous sinus to pterygoid plexus pass through fossa of Vesalli.
- ﻨDuct of Rivinus is found in sublingual gland.
- ﻨForamen transversarium transmits vertebral artery.
- ﻨKrause’s glands are lacrimal glands.
- ﻨHepatorenal pouch is Morrison’s pouch.
- ﻨCowper’s glands are found in bulbous urethra.
- Duct of Santorini is accessory pancreatic duct.
- ﻨAnterior interventricular artery is branch of left coronary artery whereas posterior one is a branch of right coronary arti
- ﻨThinnest portion of myocardial wall is left and right atria.
- ﻨThe nerve related to medial epicondyle is ulnar.
- ﻨDepressor of mandible is lateral pterygoid.
- ﻨEdinger Westphal nucleus is General Visceral Efferent.
- ﻨHofbauer cells are present in placenta.
- ﻨTranspyloric plane passes through L1 vertebra.
- ﻨSmallest cranial nerve is Trochlear.
- ﻨCharcot’s artery is a branch of middle cerebral artery.
- ﻨApelike hand occurs in median nerve palsy at wrist.
- ﻨInferior tibiofibular joint is syndesmosis type of joint.
- ﻨMandibular canal contains inferior alveolar nerve.
- Costocoracoid membrane of axilla is pierced by lateral pectoral nerve.
- ﻨMost stable position of the ankle joint is dorsiflexion.
- General sensation of nulliparous uterus is anteversion and anteflexion.
- ﻨHighest intercostal space used for liver biopsy is 8th.
- The weakest parts of inguinal canal are superficial and deep inguinal rings.
- Diaphragmatic hernia commonest on the left is traumatic hernia.
- Flexion of the knee joint takes place in the upper compartment.
- The nerve responsible for fine movements of the hand is ulnar.
- The retraction of shoulder is caused by serratus anterior.
- Accessory pancreatic duct is also called Bernard’s duct.
- Thoracic duct is also called Pecquet duct.
- Superficial fatty fascia between umbilicus and pubis is Camper fascia.
- Parasympathetic outflow from sacral plexus is nerve Erigentes.
- CSF is partly absorbed by lymphatics around I, II, VII and VIII cranial nerves.
- The appendix is most often found in retrocaecal position.
- Juxta glomerular cells are smooth muscular cells of afferent arteriole.
- Fascia of Gerota is thoracolumbar fascia.
- Isthmus of the thyroid gland is found across 3-5 th tracheal rings.
- Neural tube develops from ectoderm.
- The movement of version of the foot takes place mainly in subtalar joint, calcaneonavicular and calcaneocuboid joints.
- Incisior foramina in the mouth are foramen of Vesalli.
- Peroneal artery is a branch of posterior tibial artery.
- Unlocking of knee joint to permit flexion is caused by popliteus.
- Longest muscle or Tailor’s muscle in body is sartorius.
- Boxer’s muscle is serratus anterior.
- Toynbee’s muscle is tensor tympani.
- Muscle used for grinning is Risorius.
- OS trigonum is atavistic type of epiphysis.
- Umbilical vesicle attains full development in 4 weeks of foetal development.
- The principal sensory nerve of the larynx is the superior laryngeal nerve.
- The central canal of spinal canal is central in lumbar region.
- Atriventricular (A-V) node is supplied by right coronary artery.
- Sinoartrial node is situated at the junction of SVC and right atrium.
- Koch’s triangle is bounded by septal leaflet of tricuspid value, tendon of Todaro and orifice of coronary sinus.
- Germ cells in ovary develop from yolk sac.
- Base of heart is formed by both atria.
- Lymphatics from testes or ovaries drain into para aortic lymph nodes.
- Broca’s area is situated in inferior frontal gyrus.
- Tail of pancreas contains more islets of Langerhans.
- Saphenous opening is below and lateral to pubic tubercle.
- Thymus develops from endoderm of III pharyngeal pouch.
- Cell bodies of II order neuron for pain are situated in spinal cord.
- In Wolf Parkinson White Syndrome, there is connection between atria and ventricles.
- C-cells in thyroid gland are derived from Ultimobranchial body.
- Lymphatics from tonsil drain into Juguloomohyoid nodes.
- J receptors are situated in alveolar epithelium.
- Swallowing centre is situated in medulla.
- Angle of mandible is supplied by greater auricular nerve.
- Nasolacrimal duct drains into middle meatus.
- Injury to axillary nerve mainly causes loss of abduction.
- Wrist drop (injury in upper arm) or Saturday night palsy injury in radial groove is caused by radial nerve injury.
- Adult larynx extends from C3 to C6.
- Great vein of Galen drains into straight sinus.
- Duct of Sylvius also called cerebral aqueduct connects III and IV ventricle.
- When testicular veins are ligated, the testes are drained by cremasteric veins.
- Horner’s Syndrome consists of miosis, ptosis and anhidrosis.
- Uterus develops from Mullerian duct.
- Callot’s triangle is bounded by inferior border of liver, common hepatic duct and cystic duct.
- Failure of fusion of ostium primum and ostium secundum leads to patent foramen ovale.
- Oogonia are supplied from Yolk sac.
- Cartwheel appearance of nucleus is seen in Sertoli cells.
- Pinna is fully formed at birth.
- Ligament of Bigelow is present in hip joint.
- Uterine artery is a branch of anterior internal iliac artery.
- The narrowest part of male urethra is external meatus.
- Ophthalmic artery is a branch of cerebral part of internal cartoid artery.
- Wharton duct drains submandibular gland.
- Clavicle is the first bone to ossify.
- Paralysis of gluteus maximus is most noticeably affected the gait cycle at heel strike.
- Femur is the longest and strongest bone of the body.
- The ischiofemoral ligament is most taut when femur is extended.
- 11th and 12th ribs are floating ribs.
- Cremasteric artery is a branch of inferior epigastric.
- The largest cranial nerve is trigeminal.
- Deep artery of Penis is a branch of internal iliac.
- Ejaculation is a fraction of sympathetic nervous system whereas erection is of parasympathetics.
- Cystic artery is a branch of right hepatic.
- Trochlear nerve has the longest intracranial course.
- Vertebral veins drain into brachiocephalic veins.
- Ovum was discovered by von Baer.
- Kerckring’s centre for ossification is associated with occipital bones.
- Foramen rotundum transmits maxillary nerve.
- Gartner’s duct is a remnant of Wolffian duct.
- Primordial germ cells are first seen in wall of yolk sac.
- Father of Modern anatomy is Andreas Vesalius.
- WilliamHarveydescribed human blood circulation.
- Vocal cords are abducted by Posterior cricoarytenoid.
- Spinal cord in an adult ends at level of LI
- Mitral orifice lies at level of 4th costal cartilage.
- The central structure of axilla’ is said to be axillary artery.
- Strongest ligaments of sacroiliac joint are interosseus ligaments.
- The ligamentum arteriosum extends between the concavity of the aortic arch and the left pulmonary artery. It is remnanl the ductus arteriosus, a channel which conducted deoxygenated blood from the pulmonary artery to the aorta during fetal 1
- The transverse fissure is found only in the right lung.
- A section of the upper lobe consisting of two bronchopulmonary segments is known as the lingula.
- The surface markings from the lower border of the lungs during quiet breathing are the 6th costal cartilage, 8th rib in the axillary line, and the 1 Oth thoracic spine.
- The Thoracic duct passes through the aortic opening in the diaphragm.
- The thoracic duct drains lymph from all over the body, except from the right side of the heart and the right upper limb.
- The joint between the head of a typical rib and two vertebral bodies is synovial.
The sternal and costal parts of diaphragm are derived from the septum transversum; a gap between these two parts is known as foramen of Morgagni.
An abnormal foramna (of Bochdalek) is sometimes found between the central tendon and the lumbar section of the diaphragm, it is usually left-sided.
The pool of CSF in the lower lumbosacral region is called the lumbar cistern. It contains the roots of the lower spinal nerves (cauda equina) and the filum terminale. The spinal cord usually ends at the level of L,, in the adults. The aorta bifurcates at the level of L4. Mamillary processes are features of lumbar vertebrae. T, is responsible for the supply of the intrinsip muscles of the hand.
The only nerves contained within the spermatic cord are sympathetic nerves and the genital branch of genitofemoral nerve. A direct inguinal hernia pushes through the posterior wall of the inguinal canal, medial to the deep ring. An indirect inguinal hernia, on the other hand, passes along a patent processus vaginalis within the cord.
The formation of the portal vein by the union of the superior mesenteric and splenic veins takes place behind the neck of the pancreas.
The gastroduodenal artery is an important posterior relation of the first part of the duodenum, and is the artery which may be eroded by a posterior duodenal ulcer.
The Ligamentum teres is a remnant of the left umbilical vein, which drained into the left branch of the portal vein in the fetal liver.
The hepatic artery lies on left of CBD and the portal vein behind. Although this is the usual arrangement, variations are sometimes found.
The artery lies to the medial side of the neck of the indirect inguinal hernia; it lies lateral to a direct inguinal hernia. Pararenal fat (Zuckerkandl) is found behind the renal fascia: Perirenal fat (Gerota) lies between the capsule of the renal fascia.
- The Median umbilical ligament is a remnant of the vitelline or yolk duct.
- The external ring is an opening in the external oblique aponeurosis just above the crest of the pubis. Fertilization usually takes place in the ampulla.
- The sternal and costal parts of diaphragm are derived from the septum transversum; a gap between these two parts is known as foramen of Morgagni.
- An abnormal foramna (of Bochdalek) is sometimes found between the central tendon and the lumbar section of the diaphragm, it is usually left-sided.
- The pool of CSF in the lower lumbosacral region is called the lumbar cistern. It contains the roots of the lower spinal nerves (cauda equina) and the filum terminale. The spinal cord usually ends at the level of L,, in the adults. The aorta bifurcates at the level of L4. Mamillary processes are features of lumbar vertebrae. T, is responsible for the supply of the intrinsip muscles of the hand.
- The only nerves contained within the spermatic cord are sympathetic nerves and the genital branch of genitofemoral nerve. A direct inguinal hernia pushes through the posterior wall of the inguinal canal, medial to the deep ring. An indirect inguinal hernia, on the other hand, passes along a patent processus vaginalis within the cord.
- The formation of the portal vein by the union of the superior mesenteric and splenic veins takes place behind the neck of the pancreas.
- The gastroduodenal artery is an important posterior relation of the first part of the duodenum, and is the artery which may be eroded by a posterior duodenal ulcer.
- The Ligamentum teres is a remnant of the left umbilical vein, which drained into the left branch of the portal vein in the fetal liver.
- The hepatic artery lies on left of CBD and the portal vein behind. Although this is the usual arrangement, variations are sometimes found.
- The artery lies to the medial side of the neck of the indirect inguinal hernia; it lies lateral to a direct inguinal hernia. Pararenal fat (Zuckerkandl) is found behind the renal fascia: Perirenal fat (Gerota) lies between the capsule of the renal fascia.
- The Median umbilical ligament is a remnant of the vitelline or yolk duct.
- The external ring is an opening in the external oblique aponeurosis just above the crest of the pubis.
- Fertilization usually takes place in the ampulla.
- The Tendo calcaneus (Achilies tendon) is the common tendon of gastrocnemius, soleus and plantaris.
- The gastrocnemius is a powerful plantarflexor of the foot but can also act as a flexor of the knee.
- Both cruciate ligaments play a part in limiting medial rotation of the tibia (lateral rotation of the femur).
- The articular surfaces of the subtalar joint are covered with hyaline cartilage.
- The subtalar joint lies between the talus and calcaneus.
- The movements of inversion and eversion take place at the subtalar and talonavicular joints.
- It is medial ligament of ankle joint which is usually referred to as the deltoid ligament.
- The tibial collateral ligament is a broad flat band, the fibular collateral ligament is a rounded cord.
- The common peroneal nerve travels to the lateral side of the popliteal fossa. The tibial collateral ligament is closely related to the medial interior genicular vessels and nerve.
- The structures which pass deep to the retinaculum from medial to lateral are : tibialis posterior, flexor digitorum longus,posterior tibial vessels, tibial nerve, and flexor hallucis longus.
- A branch of the obturator artery enters the head of the femur: other nutrient vessels enter the neck of the bone.
- Tensor fasciae inserts into the iliotibial tract. Muscles which insert into the greater trochanter include gluteus medius,gluteus minimus, piriformis and obturator internus. Obturator externus inserts into the trochanteric fossa.
Blood brain barrier is made up of : (1) the vessel wall; (ii) the arachnoid layer of perivascular sheath; (iii) the perivascular space; (iv) the pial layer of perivascular sheath, and (v) the neuroglia and the ground substance of the brain. The barrier, at the capillary level, is reduced to the mere capillary endothelium with neuroglia and ground substance.
Hemiplegia of an upper motor neuron type is usually due to an internal capsular lesion caused by thrombosis of one of the lenticulostriate branches of the middle cerebral artery (cerebral thrombosis).
One of the lenticulostriate branches is most frequently ruptured (cerebral haemorrhage); it is known as Charchot’s artery ofcerebral haemorrhage. This lesion also produces hemiplegia with deep coma, and is ultimately fatal.
Thrombosis of the Huebner’s recurrent branch of anterior cerebral artery causes contralateral upper monoplegia.
Thrombosis of paracentral artery (terminal cortical branch of anterior cerebral artery) causes contralateral lower monoplegia.
Thrombosis of posterior inferior cerebellar artery causes lateral medullary syndrome (Wallenberg’s syndrome). It is characterized by :
- Severe giddiness, due to involvement of vestibular neclei
- Dysphagia, due to involvement of the nucleus ambiguus.
- Crossed hemianaesthesia, due to involvement of the lateral spinothalamic tract (contralateral body) and nucleus of the spinal tract of trigeminal nerve (ipsilateral face).
- Horner’s syndrome due to involvement of sympathetic pathway in the medulla.
- Cerebellar symptoms and signs.
Pontine haemorrhage is characterized by (i) paralysis (contralateral hemiplegia); (ii) deep ctfma; (iii) hyperpyrexia; and (iv)pin-point pupil. It is invariably fatal.
The hunger or feeding centre is placed laterally; the satiety centre, medially in hypothalamus.
The thirst or drinking centre is situated in the lateral part of hypothalamus.
- Father of Anatomy— Herophilus.
- Largest organ of body— Skin.
- Largest sesamoid bone of body—Patella
- Largest gland of body— Liver.
- Largest branch of femoral artery— Profunda femoris artery.
- Largest ganglion of neck is —Superiorcervical ganglion.
- Largest vein of body is —long saphenous vein.
- First teeth to appear in infant are —Lower central incisor.
- First permanent teeth to appear are —First Molar.
- First bone to ossify in body—Clavicle.
- Second bone to ossify in body — Mandible.
- Most common cause of nerve root compression in neck — Cervical spondylosis.
- Embryonic disk develops during Third week.
- Largest branch of femoral Nerve —Saphenous nerve.
- where parietal bones meet each other.
- First endocrine gland to appear in foetus—Thyroid gland.
- Bregma is the point—Where sagital and coronal sutures meet.
- Lambda is the point—Where sagittal and lambdoid sutures meet.
- Lambda lies at the location of — Posterior fontanelle.
- Lambdoid suture lies between —Parietal and occipital bones.
- Sternocleidomastoid is innervated by —Spinal accessory N. & C2, C3 Spinal N.
- Trapezius is innvervated by —Spinal accessory N. &C3, C4 Spinal N.
- Minimum time required for irreversible brain death due to ischemia—Four minutes.
- Clinically most important layer of scalp is —Loose areolar tissue.
- Kyphosis is an exaggerated thoracic curvature.
- Lordosis is an exaggerated lumbar curvature.
- Scoliosis is a lateral curvature.
- First cervical vertebral is called Atlas.
- Second cervical vertebra is called Axis.
- An upward projection present in second cervical vertebra is called Dens.
- Transverse foramen is characteristic of Cervical vertebrae.
- Transverse formen transmits Vertebral artery.
- Structure transmitted in intervertebral canal is Spinal nerve.
- Nucleus pulposus, is the remnant of Notochord.
- Digastric triangle and submandibular fossa of mandible.
Sphenoethmoidal recess is a depression lying above and behind the superior choncha. It receives the opening of sphenoidal air sinus.
Superior meatus receives the opening of posterior ethmoidal air sinuses.
Middle meatus receives the opening of middle ethmoidal air sinuses on or above the bulla ethmoidalis and maxillary sinus opening in the floor of hiatus semilunaris.
Anterior meatus receives the opening of naso lacrimal duct. Opening is guarded by a fold of mucous membrane which forms a valve.
Uvula is a conical (projection) process hanging from middle of posterior border of soft palate.
Dorsal surface of tongue is divided into posterior 1/3 and anterior 2/3 by a ‘V shaped sulcus terminalis. Papillae of the tongue are filiform, fungiform and circumvallate papillae
Foreign body removal from pyri form fossa may damage the internal laryngeal nerve resulting in anaesthesia of laryngeal mucous membrane upto vocal cords.
Erb’s point’ is the meeting point of two roots C3, C6, two divisions of upper trunk (anterior and posterior); and two nerves viz. supra scapular and nerve to subclavius. Stretch of this point leads to Erb’s paralysis.
External Jugular vein pierces the deep cervical fascia before it drains into the subclavian vein. The walls of the vein are adherent to the deep fascia and this factor prevents the retraction of vein when cut. Hence the opening should immediately be closed by applying pressure otherwise air may be sucked in during inspiration.
True capsule of thyroid gland has to be removed during thyroidectomy along with the gland as the major vessel trunks pass through the space between true and false capsules and there is a rich plexus of vessels immediately beneath the true capsule. Rupture of veins draining from upper part of nasal septum (Joining the inferior cerebral veins in cranium) may be the source of severe nasal bleeding in elderly hypertensive patients.
Sibson’s fascia is Suprasternal space.
Suprasternal space of ‘Burns’ is space above upper margin of manubrium sterni with in the general investing layer of deep cervical fascia.
Typical intercostal space is the space present between two typical ribs (i.e 3rd, 4th, 5th and 6th spaces) and transversed by vessels and nerves confined to thoracic wall. Angle of Louis is sternal angle.
Typical intercostal nerves are 3rd, 4th, 5th, 6th, intercostal nerves; these run in typical intercostal space and supply the structures of that intercostal space only.
- Anteriorly 2nd to 4th tracheal rings are related to isthmus of thyroid gland.
- Trachea divides into right and left principal bronchi, Right principal bronchus is 2.5 cm long and in line with trachea and left runs transversely.
- Right principal bronchus divides into 3 lobar bronchi and left principal bronchus divides into 2 lobar bronchi.
- There are 10 bronchopulmonary segments in each lung.
- In its course thoracic duct is behind and to the right of oesophagus in the lower part, crosses the midline at 5th thoracic vertebral level behind oesophagus then lies to the left of oesophagus in the rest of its course.
- Thoracic duct passes from abdomen to thorax through aortic opening of diaphragm.
- Suprapleural membrane is a membrane which expands over cervical pleura and is attached infront to the 1st rib and behind to the transverse process of 7th cervical vertebra. This is also called Sibson’s fascia.
- Innervation by intercostal nerves makes the parietal pleura sensitive to pain.
- Arrangement of structures in each intercostal space is vein, artery and nerve (VAN) from above downwards except in upper spaces. Here the nerve is at first above the posterior intercostal artery. ‘
- Symphathetic nerves cause bronchodilatation. 1
- Suprapleural membrane is regarded as the tendon of scalenus minimus.
- Fibers from thoracic part of sympathetic trunk pass in greater splanchnic (branches of 5th to 9th ganglia); lesser spanchnl (branch of 12th thoracic ganglion) nerves.
- Weakest point of the rib is the region infront of the neck. This is the usual site for fracture.
- Mediastinal and central diaphragmatic pleura are innervated by phrenic nerve; hence irritation causes referred pain to should tip or lower neck i.e. the area of skin supply by same spinal segments (C3, C4).
- Diagnostic radiological finding in pleural effusion is obliteration of costo diaphragmatic recess.
- Achalasia (cardio-spasm) is due to congenital absence of nerve cells of oesophagus resulting in neuromuscular incoordination
- Telencephalon is End brain (cerebral hemispheres).
- Diencephalon is Thalamus, epithalamus, hypothalamus, subthalamus.
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