practice

Explanation

Explanation

Origin

Long head of triceps: infraglenoid tubercle of scapula

Long head of biceps: supraglenoid tubercle of scapula

Medial head of triceps: posterior surface of humerus, distal(inferior) to radial groove.

Lateral head of triceps: posterior surface of humerus, proximal(superior) to radial groove.

Short head of biceps: coracoid process of scapula

Explanation

Palmar interosseous muscles: adduction of the digits to the axial line/midfinger (finger III)

Dorsal interosseous muscles: abduction of the digits from the axial line.

Explanation

Postcentral gyrus (i.e. part of parietal lobe immediately posterior to central sulcus) is concerned with sensory information (touch).

Precentral gyrus (i.e. part of frontal lobe immediately anterior to central sulcus) is concerned with motor information. Occipital lobe: visual cortex. Cerebellum: coordination of movement and postural adjustment. Temporal lobe: superior temporal gyrus – located in temporal lobe immediately below sylvian fissure concerned with auditory stimuli. Hippocampus - memory

Explanation

Rubrospinal tract: red nucleus – lateral white column (spinal cord); controls muscle tone, because of its connections with cerebellum, vestibular apparatus and skeletal muscle.

Corticospinal tract: anterior and lateral – control of voluntary movements. Forms upper motor neuron (UMN).

 Corticonuclear tract: innervates muscles of the face, head and neck. Spinothalamic tract: anterior – crude touch sensation; lateral – pain and temperature sensations.

Tectospinal tract: control of movement of head in response to visual and auditory impulse.

Explanation

Postcentral gyrus (i.e. part of parietal lobe immediately posterior to central sulcus) is concerned with sensory information (touch).

Precentral gyrus (i.e. part of frontal lobe immediately anterior to central sulcus) is concerned with motor information. Occipital lobe: visual cortex. Cerebellum: coordination of movement and postural adjustment. Temporal lobe: superior temporal gyrus – located in temporal lobe immediately below sylvian fissure concerned with auditory stimuli.

Explanation

* Omental bursa is a closed part of peritoneal cavity, lying posterior to the stomach and lesser omentum.

* Pregastric or Antegastrial: lies anterior to the stomach.

* Hepatic bursa: embraces the right lobe of liver, gallbladder, upper pole of right kidney and right suprarenal gland.

* Right lateral channel (right paracolic gutter/sulcus)

* Left lateral channel (left paracolic gutter/sulcus)

Explanation

* Ramus circumflexus (circumflex coronary artery) branch of left anterior descending artery runs within – left coronary sulcus.

* Arteria coronaria dextra (right coronary artery) – right coronary sulcus.

* Ramus interventricularis posterior (posterior interventricular branch): runs along the sulcus of the same name; greatest branch of right coronary artery

* Ramus interventricularis anterior (anterior interventricular branch): runs along the sulcus of the same name.

* Vena cordis parva (small cardiac veins): right portion of coronary sinus.

Explanation

Anterolateral abdominal wall has 9 regions and 4 quadrants (RUQ, LUQ, RLQ, LLQ)

·        Right lateral abdominal region: Ascending colon (colon ascendens), right kidney, right ureter and loops of small intestine.

·        Umbilical region: Transverse colon (colon transversum), head of pancreas, duodenum (except superior part)

·        Left lateral abdominal region: Descending colon (colon descendens), left kidney, left ureter and loops of small intestine.

·        Left inguinal region: Sigmoid colon (colon sidmoideum), left ureter, left external iliac artery of artery and vein.

·        Right Inguinal region: Caecum, vermiform appendix, right ureter

Explanation

Mimic muscles on the face and the stapedius muscle are supplied by the facial nerve (CN VII). So, paralysis of this nerve can lead to this symptoms. Facial nerve disorders may also manifest as taste acuity loss or impaired secretion of the lacrimal and salivary glands. Other muscles listed are not directly involved in hearing, as compared to the stapedius muscle, which is connected to the stapes (ear ossicle).

Explanation

Olfactory receptors (1^st order neuron) → Mitral cells (2^nd order neuron) → Olfactory tract → Olfactory trigone, anterior perforated substance, septum pellucidum (3^rd order neuron) → Uncus of parahippocampal gyrus.

The Olfactroy analyzer is one of the oldest ones so it features several fibers that take the shortest route to the Olfactory cortex i.e. do not relay within the thalamus.

Gustatory: through its 2^nd order neuron from medial lemniscus → thalamus.

Visual: through its subcortical visual centers → pulvinar of thalamus

Tactile (skin analyzer); Auditory: through lateral lemniscus of inferior colliculi of tectal plate and medial geniculate bodies of metathalamus.

Explanation

Reticular formation is a diffused mass of neurons and nerve fibers which form an ill-defined meshwork of reticulum in central portion of the brainstem. Functions: Ascending reticular activating system (ARAS) and descending reticular system. The ARAS is concerned with arousal, alertness, attention and wakefulness, emotional reactions, learning processes and conditioned reflexes. Hence, tumor or lesion in ARAS leads to prolonged sleeping or coma.

Explanation

Linea terminalis = pectineal line (pubis) + Arcuate line + sacral promontory + superior margin of pubic symphysis. Boundary between the abdominal and pelvic cavity.

Linea semilunaris found on the lateral margin of rectus abdominis.

Linea arcuata: the region on the posterior layer, where aponeuroses end and continue into the anterior layer. Part of linea terminalis anteriorly.

Explanation

Encephalitis is inflammation of the brain. 4 ventricles containing cerebrospinal fluid (CSF) within the brain. CSF is formed by the choroid plexus, within the cerebral ventricles. CSF moves from the lateral ventricles (right and left) → interventricular foramen (of Monro) → 3^rd ventricle → cerebral aqueduct (of sylvius) → 4^th ventricle. An ↑ in CSF pressure in right lateral ventricle is due to obstruction or closure of the right interventrcular foramen preventing outflow of CSF.

Explanation

Explanation

The inferior lobe of left lung has 5 segments: superior, medial basal, anterior basal, lateral basal, posterior basal segments.

Explanation

Anterior (ventral, motor) spinal cord root: arises from the anterolateral sulcus and contains a set of axons of motor neurons located within the anterior columns; the anterior roots number 31 pairs. The roots of the segments C₈ through L₂ also comprise the autonomic (sympathetic) fibers that arise from the sympathetic nuclei of the lateral grey columns.

Explanation

Normal hearing: air conduction should be greater than bone conduction. Air conduction uses the (pinna, eardrum and ossicles) to amplify and direct the sound whereas bone conduction bypasses some or all of these and allows the sound to be transmitted directly to the inner ear. In conductive hearing loss, bone conduction is better (louder) than air (negative Rinne test). This confirms the diagnosis that the left part of the ear has a problem with conduction of sound to the inner ear → left middle ear. In this case the inner ear is normal since the patient can still hear. It is therefore, a pathology of either the pinna (outer ear), eardrum or ossicles (middle part of ear).

Explanation

The mesentery fixes the intestine to the posterior abdominal wall; its posterior margin is short (15-20mm) and is called the root of mesentery directed obliquely from the duodenojejunal flexure at the left side of the second lumbar vertebra to the right of sacroiliac joint.

Explanation

Urinary incontinence – involuntary urination. In general, parasympathetic stimulation are anabolic, promoting normal function and conserving energy. The sacral part of parasympathetic system reside within the S₂-S₄ sacral segments of the spinal cord. They inhibits contraction of internal sphincter of bladder, contracts detrusor muscle of the bladder wall causing urination (voluntary). Lesion to this segment of spinal cord (S₂-S₄) causes involuntary urination.

Explanation

Boundaries of femoral triangle:

*Superiorly: inguinal ligament

*Medially: medial border of adductor longus muscle

*Laterally: medial border of the Sartorius muscle

*Roof: fascia lata

*Floor: adductor longus muscle, pectineus muscle and the iliopsoas muscle

Explanation

Fascia of the neck:

Superficial cervical fascia: investing fascia; it lies beneath the platysma muscle and surrounds all of the deeper structures of the neck. Within the borders of the lateral neck triangle, the superficial layer of the cervical fascia splits; its superficial sheet runs towards the back, encloses the trapezius forming its fascial sheath; its deeper sheet attaches to the transverse processes of the cervical vertebrae.

Deep cervical fasciae: pretracheal; prevertebral; fascia of the carotid sheath

Explanation

External jugular vein is a subcutaneous vein that arises by the union of the anterior (which is the anastomosis with the retromandibular vein) and posterior (formed of the occipital and posterior auricular veins). External jugular vein crosses the sternocleidomastoid muscle laterally and at its midpoint, it then opens into the venous angle – the junction point of the subclavian and internal jugular veins.

Explanation

Resistance to intrahepatic blood flow due to intrasinusoidal hypertension. Anastomoses between portal vein (vena porta hepatis) tributaries and the arterial system. Complications: ascites, periumbilical venous collaterals (caput medusa); esophageal varices; congestive splenomegaly; hemorrhoids

↑in blood pressure in portal vein → portal hypertension

Explanation

* Triceps brachii is the chief extensor of the forearm at the humeroulnar joint. Has a long, lateral, and medial head. Inserts on olecranon of ulna bone.

*Infraspinatus muscle: Lateral (external) rotation of the humerus at the glenohumeral joint, also assists in holding the head of the humerus in the glenoid fossa.

*Teres Major muscle: Adduction & medial rotation of the humerus at the glenohumeral joint shoulder joint)

*Subscapularis muscle: Medial (internal ) rotation and adduction of the humerus at the glenohumeral joint, also assists in holding the head of the humerus in the glenoid fossa.

*Levator scapulae muscle: Elevates the scapula.

Explanation

The ankle is where the leg and foot meet (talocrural joint). This joint is formed by the Tibia (medially), Fibula (laterally) and Talus. Inner/medial surface of the ankle is formed by the medial malleolus of Tibia. The inferomedial process of the Tibia forms the medial malleolus. The inferior process of the Fibula forms the lateral malleolus. Lower third of the Fibula is located laterally. Calcaneus is a tarsal bone and is not involved in forming the ankle joint.

Explanation

Axillary nerve innervates the muscles (e.g. deltoid) that abduct the upper limb.

Deltoid muscle:

Origin: lateral third of clavicle, acromionof scapula, spine of scapula.

Insertion: Deltoid tuberousity of humerus.

Innervation: Axillary nerve ( a terminal branch of branchial plexus receiving fibres from C5 & C6 ventral rami.

Action:

Anterior part- flexion & medial (internal) rotation of the humerus at glenohumeral joint.

Middle part- abduction of the humerus at the glenohumeral joint.

Posterior part – extension & lateral (external) rotation of the humerus at the glenohumeral joint.

Explanation

Explanation

Lateral rectus muscle: Abducts the eyeball (pulls it away from the midline) & it’s supplied by the abducent nerve (CNVI) which abducts the eye, pulling it laterally. A lesion of CNVI will lead to failure of eye to abduct.

Explanation

The cruciate ligaments are located in the middle of the joint. The ligaments serve to stabilize the femur and tibia. We have the anterior and posterior cruciate ligament. Drawer test is performed by pulling the tibia anteriorly and posteriorly with a flexed knee. Injury to the cruciate ligament will show a drawer sign with abnormal laxity of the tibia.

Explanation

* Vena magna cordis (Great cardiac vein): originates in the area of the apex of the heart. The vein runs along the anterior interventricular sulcus, turns left and enters the coronary sulcus.

* Vena cordis media (middle cardiac vein): also originates on the apex of the heart. It ascends along the posterior interventricular sulcus and joins the coronary sinus next to its opening.

* Vena cordis parva (small cardiac veins): situated within the right portion of coronary sinus. It originates from the area of right ventricle and runs leftwards to reach the coronary sinus.

* Vena(e) posterior ventriculi sinistri [posterior vein(s) of left ventricle]: originates from several small veins on the posterior surface of left ventricle and flows either into the coronary sinus or into the terminal portion of great cardiac vein.

* Vena oblique atria sinistri (oblique vein of left atrium): runs obliquely along the posterior surface of left ventricle and flows into the coronary sinus next to the great cardiac vein.

These 5 veins are the veins related to the coronary sinus.

Explanation

Round ligament of liver (ligamentum teres hepatis): it runs from the visceral surface to the navel; it is an obliterated peritoneum–enfolded umbilical vein. The orifice of the vein may remain partially patent (open) and thus the vein can be used for infusion of drugs and radiopaque agents. The umbilical vessels closure occurs during the first week of life; the umbilical vein transforms into peritoneum–enfolded round ligament of liver. The umbilical arteries also close and transform into the medial umbilical ligaments. The single umbilical vein is responsible for carrying oxygenated blood from placenta to fetus in fetal circulation.

Explanation

The thoracic part of the thoracic duct resides anterior to the vertebral column, in between the aorta and the azygos vein and posterior to the esophagus. Lymphatic vessels of the esophagus may pass directly to the thoracic duct or to the posterior mediastinal nodes. Lymphatic vessels of the trachea drain into pretracheal, paratracheal and inferior deep cervical nodes to the jugular trunk → thoracic duct. Pericardium is drained by parasternal nodes, lateral pericardial nodes and prepericardial nodes. Heart is drained by brachiocephalic nodes, nodes of arch of azygos, node of ligamentum arteriosum. The bronchopulmonary nodes and tracheobronchial nodes drain the left main bronchus. The syntopy of the esophagus allow direct drainage into the thoracic duct (both lie on the left part of thoracic cavity in the posterior mediastinum).

Explanation

The subclavian artery becomes the axillary artery at the lateral border of the first rib. The axillary artery becomes the brachial artery at the inferior borders of Pectoralis major (anteriorly) and Latissimus dorsi (posteriorly). Therefore, a cut wound of the anteromedial region of shoulder will damage the brachial artery. Subscapularis is the greatest branch of axillary artery. Radial artery and ulnar artery are terminal branches of brachial artery in the cubital fossa. Profunda is the greatest branch of brachial artery arising from its upper portion.

Explanation

The small intestine: duodenum, jejunum, ileum

Duodenum: superior part, descending part, inferior part and ascending part. The descending part of the duodenum runs inferiorly, curving around the head of pancreas. The bile and main pancreatic ducts enter its posteromedial wall. These ducts usually unite to form the hepatopancreatic ampulla, which opens on an eminence called the major duodenal papilla (papilla duodeni major) located posteromedially in the descending duodenum.

Explanation

The left kidney neighbors the left suprarenal gland, the pancreas, the stomach, the left colic flexure and the small intestine. The stomach is the best answer in the options given when referring to the upper third of the kidney; the small intestine lies much lower in the abdominal cavity.

Explanation

Explanation

The neck of the urinary bladder (cervix vesicae) is the narrow portion of fundus, which becomes continuous with the urethra. The urethra begins with the internal urethral orifice within the neck of the bladder, passes through the prostate. As shown in the image above, the cervix of the urinary bladder is the closest part to the prostate gland for metastases of any tumor or infectious agent.

Explanation

Explanation

The bronchi form the bronchial tree that consists of main bronchi, lobar bronchi, segmental bronchi and their branches and terminal bronchioles. We have 2 main/primary/principal bronchi: left and right. Left main bronchus (bronchus principalis sinister) is approximately 4-5cm long; is longer and narrower than the right main bronchus. It runs slantwise leftwards to enter the hilum of left lung. The left main bronchus neighbors the arch of aorta anteriorly and the descending aorta and esophagus posteriorly. Right main bronchus neighbors the azygos vein, which runs crosswise. All other branches of the bronchi tree are found in the lungs.

Explanation

Mental artery is the terminal branch of inferior alveolar artery. It supplies the mental region (chin) and the lower lip.

Inferior labial is a branch of facial artery that supplies the lower lip. Lingual artery supplies the tongue. Facial artery gives branches such as ascending palatine artery, submental artery, superior and inferior labial arteries and angular artery. Palatine artery supplies the palate.

Explanation

 Lingual nerve is a branch of mandibular nerve (CNV₃). Mandibular nerve is the third division of the trigeminal nerve. It is a sensory nerve that transmits the impulses of pain, temperature and tactile sensitivity. Glossopharyngeal provides taste and tactile sensory innervations to the posterior 1/3 of the tongue.

Explanation

 The Ulnar nerve arises from the medial cord of the brachial plexus. It runs along the medial bicipital groove, and proceeds to the ulnar groove situated on the posterior surface of the medial epicondyle of humerus. There the nerve runs covered by fascia and skin only.

Musculocutaneous nerve arises from the lateral cord then traverses the coracobrachialis and appears in between the biceps brachii and the brachialis muscles.

Dorsal scapular nerve (nervus dorsalis scapulae) runs to the levator scapulae and the rhomboid muscles.

Subscapular nerve (nervus subscapularis) supplies the subscapularis and the teres major muscle.

Radial nerve (nervus radialis) arises from the posterior cord of brachial plexus. It passes the radial canal along with deep artery of arm. The nerve quits the canal via its inferior opening (in between the brachialis and the brachioradialis muscle) that leads to the cubital fossa; here at the head of radius, the nerve splits into the superficial and deep branches.

Explanation

     Deltoid muscle (M. deltoideus): abducts the shoulder; anterior fibers flex the shoulder, while posterior fibers extend it.

Triceps brachii and anconeus extends the forearm; the long head of triceps brachii extends and adducts the shoulder; coracobrachialis muscle flexes and adducts the arm; supinators rotates (supinates) the forearm.

Explanation

In the female lesser pelvis, there are two excavations: the rectouterine pouch and vesicouterine pouch. The rectouterine pouch (pouch of douglas) is an intraperitoneal space between the uterus and the rectum. It is a common place for pelvic fluid or blood from hemorrhage to collect after surgery, or rupture of any etiology.

The vesicouterine pouch is between the urinary bladder anteriorly and the uterus posteriorly. It is a shallower recess (pouch).

Explanation

Obturator artery reaches the thigh region via the obturator canal. The artery supplies the adductors of thigh and the hip joint. The hip joint receives blood from the acetabular branch, which passes within the ligament of head of femur. The obturator artery anastomoses with the inferior hypogastric artery via the pubic branch.

Femoral artery arises directly from the external iliac artery. On leaving the vascular space, it appears within the femoral triangle together with the femoral nerve (laterally) and femoral vein (medially).

The external iliac artery descends on the medial aspect of psoas major muscle and quits the lesser pelvis via the vascular space to become continuous with the femoral artery. Common iliac arteries gives both external and internal iliac arteries.

Inferior gluteal artery leaves the lesser pelvis cavity via the infrapiriform foramen. Within the gluteal region, it supplies the gluteus maximus and other related muscles.

Internal pudendal artery passes inferolaterally, anterior to the piriformis muscle and sacral plexus. It leaves the pelvis between the piriformis and the coccygeus muscles by passing through the inferior part of the greater sciatic foramen.

Explanation

Anterior (ventral, motor) spinal cord root: arises from the anterolateral sulcus and contains a set of axons of motor neurons located within the anterior columns; the anterior roots number 31 pairs. The roots of the segments C₈ through L₂ also comprise the autonomic (sympathetic) fibers that arise from the sympathetic nuclei of the lateral grey columns.

Explanation

The floor of the urinary bladder houses the trigone of urinary bladder. The trigone lacks the rugae as the submucosa is scarce here and mucosa adheres directly to the muscular layer. The vertices of trigone are related to the ureteric orifices and the internal urethral orifice. It is located at the fundus of bladder – lower wide and dense portion.

Explanation

Hepatoduodenal ligament running from the porta hepatica to the superior part of the duodenum. It consists of double layer of peritoneum and enfolds 3 structures:

·        Common hepatic artery

·        Portal vein

·        Common bile duct

Portal vein is localized posteriorly; hepatic artery – left anterior and bile duct – right anterior.

Explanation

          The pylorus is a thickened part of the stomach which becomes continuous with the initial part of duodenum. The duodenum begins at the pyloric part of stomach and divided into 4 parts: superior part, descending part, inferior (horizontal) part and the ascending part. The superior part (pars superior) 5cm long, begins from the pylorus and runs horizontally and slightly backwards. On forming the superior duodenal flexure, the intestine passes into the descending part.

Explanation

The main (primary or first-order) bronchus branches in the hilum of lungs to form the lobar bronchi (secondary), which ventilate the respective lobe. The lobar bronchi in turn branch to form the tertiary (third-order) bronchi called the segmental bronchi. They ventilate the pulmonary areas called segments. Segments are the pyramidal shaped portions of lungs with apices facing the lung root and bases at the lung surface. Each segment excluding the segmental bronchus has a segmental branch of the pulmonary artery respective to segmental bronchi branches. The branches of pulmonary veins run between the segments. Ant segment is surgically removable without major damage to neighboring segments.

Explanation

The thymus resides in the anterior mediastinum posterior to the manubrium of sternum reaching the IV rib. Mediastinal pleurae neighbor the thymus laterally, the pericardium, arch of aorta with associated branches and inferior vena cava posteriorly. Topographically, the thymus is closer to the sternum than the heart. So it will be affected first by a blow to the sternum because it lies outside of the pericardial cavity (anterior to the fibrous pericardium).

Explanation

Lordosis is an exaggerated anterior curvature of the spine, most often lumbar. Lordosis is present in the cervical and lumbar regions (cervical and lumbar lordoses). The intervertebral synchondroses and symphyses are reinforced by the longitudinal ligaments which run along the entire spine.

·        Anterior longitudinal ligament is a band which extends from the atlas to the pelvic surface of the hip bone along the anterior surfaces of the vertebral bodies.

·        Posterior longitudinal ligament runs along the posterior surface of the vertebral bodies (in the vertebral canal).

Therefore, a damage to the anterior longitudinal ligament can induce lordosis.

Explanation

The lingual artery arises at the level of posterior horn of the hyoid bone from the external carotid artery. The artery occupies the lingual triangle (of Pirogov) immediately below the hyoglossus muscle. It gives the dorsal lingual branches, deep lingual artery and sublingual artery.

Explanation

Fontanelles are large fibrous areas where several sutures meet; often called “soft spots” on an infant’s head. The two largest fontanelles are the anterior and posterior fontanelles on the superior surface of the neurocranium. The fontanelle in the back of the head (posterior fontanelle) usually closes by the time an infant is 2-3 months old. The fontanelle at the top of the head (anterior fontanelle) usually closes between 7-18months. In adults the remnants of the anterior fontanelle is the bregma and the posterior fontanelle is the lambda.

Explanation

The axillary nerve (nervus axillaris) from brachial plexus, is the greatest branch of the short branches of brachial plexus. It arises from the posterior cord and proceeds to the quadrangular/quadrilateral foramen. It supplies the deltoid and teres minor muscles. The axillary nerve and posterior circumflex humeral artery pass through the quadrangular space. Borders of the quadrangular space:

·        Superior: Teres minor

·        Inferior: Teres major

·        Medial: Long head of triceps

·        Lateral: humerus

Explanation

The facial artery (arteria facialis) arises somewhat above the lingual artery from the external carotid artery. Then the artery enters the submandibular gland to give the glandular branches. Upon passing the gland, the artery loops around the mandible edge (inferior border), anterior to the mandibular angle to reach the facial area. It ascends along the anterior border of the masseter muscle in direction of the medial angle of eye. At the medial angle of eye, it gives its terminal branch – angular artery which forms an anastomosis with dorsal nasal artery of ophthalmic artery, thereby creating an anastomosis which connects both internal and external carotid arteries.

Explanation

       The muscles of the hand are divided into 3 groups: muscles of the thumb (thenar muscles); muscle of the fifth digit (hypothenar eminence) and central palmar muscles. Flexor pollicis longus (long flexor muscle of thumb) resides laterally in the deep layer. It flexes the thumb.  Its tendon passes under the flexor retinaculum onto the palm and inserts into the base of the distal phalanx of the thumb.

Flexor pollicis brevis (short flexor muscle of thumb) and abductor pollicis brevis (short abductor muscle of thumb) attaches to the base of the proximal phalanx of the thumb. Opponens pollicis (opposer muscle of thumb) attaches to the first metacarpal bone. It is the deepest of the thenar muscles. Abductor pollicis (abductor muscle of thumb) inserts into the base of the proximal phalanx of the thumb.

NB: first (I) finger – Thumb

Explanation

Common carotid artery branches to give: external carotid artery and internal carotid artery.

External carotid artery → facial artery → angular artery

Internal carotid artery → ophthalmic artery → dorsal nasal artery

Angular artery is the terminal segment of facial artery which branches within the medial angle of the eye. It anastomoses with the branches of the ophthalmic artery (i.e. the dorsal nasal artery). The two big arteries connected are the external carotid artery and the internal carotid artery.

Explanation

The thoracic aorta is a continuation of the aortic arch. It resides within the posterior mediastinum next to the vertebral column. The thoracic aorta passes through the aortic hiatus to become continuous with the abdominal aorta. Other neighboring organs are the thoracic duct (found on the left), the azygos and hemiazygous veins and the left sympathetic trunk. The thoracic duct resides anterior to the vertebral column, in between the aorta and the azygos vein and posterior to the esophagus. In the course of weight lifting there is increased arterial blood pressure which stretches the thoracic aorta and this can compress the thoracic duct while passing through the aortic hiatus.

Aortic hiatus is one of the openings of the diaphragm which resides in the middle between the right and left crura. Above, it is bounded by the median arcuate ligament that prevents the aorta from being constricted. Beside the aorta, the thoracic lymphatic duct also passes through the aortic hiatus. Other openings of diaphragm includes the esophageal hiatus for esophagus; caval opening for inferior vena cava.

Explanation

Axillary nerve innervates the muscles (e.g. deltoid) that abduct the upper limb.

Deltoid muscle:

Origin: lateral third of clavicle, acromionof scapula, spine of scapula.

Insertion: Deltoid tuberousity of humerus.

Innervation: Axillary nerve ( a terminal branch of branchial plexus receiving fibres from C5 & C6 ventral rami.

Action:

Anterior part- flexion & medial (internal) rotation of the humerus at glenohumeral joint.

Middle part- abduction of the humerus at the glenohumeral joint.

Posterior part – extension & lateral (external) rotation of the humerus at the glenohumeral joint.

Explanation

The glossopharyngeal nerve (CN IX) is the mixed type nerve. It comprises the motor, sensory and autonomic fibers. It gives numerous branches but the lingual branches run to the posterior third of lingual mucosa. The nerve comprises the fibers of general sensitivity and the gustatory (taste) fibers that supply the taste buds.

·        Anterior 2/3 of tongue is supplied by chorda tympani, a branch of CN VII (facial nerve) for taste sensation.

·        Anterior 2/3 of tongue is supplied by CN V₃ (mandibular division of the trigeminal nerve) for tactile sensation.

·        Posterior 1/3 of tongue is supplied by CN IX (glossopharyngeal nerve) for taste and tactile sensation.

Explanation

     The femur consists of a shaft (body) and two ends, superior/proximal and inferior/distal. The neck of the femur is trapezoidal, with its narrow end supporting the head and its broader base being continuous with the shaft. Fracture of the femoral neck is a very common occurrence in older people as a result of a slight stumble if the neck has been weakened by osteoporosis.

Explanation

What forms the walls of the inguinal canal:

·        Anteriorly: the aponeuroses of the external and internal oblique muscles.

·        Posteriorly: the transversalis fascia.

·        Superiorly: the arching fibers of the internal oblique and transverses abdominis muscles.

·        Inferiorly: the inguinal ligament.

Contents:

·        Men: Spermatic cord (funiculus spermaticus) and the ilioinguinal nerve

·        Women: round ligament of the uterus (ligamentum teres uteri) and the ilioinguinal nerve.

      Since the gender was not specified in the question, then it means the question s referring to inguinal canal content in men, which is the Funiculus spermaticus.

Explanation

The anterior jugular vein arises from small superficial veins of the sublingual area. The veins descend to the manubrium of sternum and merge to form the jugular venous arch. The lateral ends of the arch open into the external jugular vein before it joins the venous angle.

NB: veins are located superficially to arteries.

Explanation

Anterolateral abdominal wall has 9 regions and 4 quadrants (RUQ, LUQ, RLQ, LLQ)

·        Right lateral abdominal region: Ascending colon (colon ascendens), right kidney, right ureter and loops of small intestine.

·        Umbilical region: Transverse colon (colon transversum), head of pancreas, duodenum (except superior part)

·        Left lateral abdominal region: Descending colon (colon descendens), left kidney, left ureter and loops of small intestine.

·        Left inguinal region: Sigmoid colon (colon sidmoideum), left ureter, left external iliac artery of artery and vein.

·        Right Inguinal region: Caecum, vermiform appendix, right ureter

Explanation

The inferior mesenteric artery arises from the anterior aspect of the abdominal aorta. The artery gives the branches as follows: left colic artery (arteria colica sinistra); sigmoid arteries (supplies sigmoid colon) and superior rectal artery (supplies the rectum). Left colic artery (sinister colic) ascends leftwards to supply the descending colon. On reaching the intestine, the artery gives the ascending and descending branches that anastomose with the middle colic artery and sigmoid artery.

Explanation

The walls of the tympanic cavity (6): tegmental wall, jugular wall, labyrinthine wall, membranous wall, carotid wall and mastoid wall. The mastoid wall (paries mastoideus) is the posterior wall related to the mastoid process of temporal bone. The opening on the wall – the aditus, to mastoid antrum leads to the greatest air cell called the mastoid antrum (antrum mastoideum) and further to smaller mastoid air cells.

Explanation

The facial nerve (CNVII) comprises mostly the motor fibers that arise from the motor nucleus of facial nerve. These fibers supply the facial muscles. The following branches supply the mimic muscles: temporal, zygomatic, buccal, marginal mandibular and the cervical branches. Clinical applications: conductivity disorders in the facial nerve result in paralysis of the facial muscles. This may be caused by chilling (cold) that develops into neuritis. The state is manifested by facial asymmetry. The patient cannot close the eyes and raise the eyebrows – as a result of temporal branch defect that supplies orbicularis oculi; cannot bare his teeth – as a result of marginal mandibular branch defect that supplies the mental and oral muscles.

Explanation

Dorsal interosseous muscles: abduction of the digits from the axial line.

Palmar interosseous muscles: adduction of the digits to the axial line/midfinger (finger III)

Explanation

There are nine flexor tendons in the carpal tunnel. The flexor tendons of the fingers, the flexor digitorum superficialis (FDS) and flexor digitorum profundus (FDP), are arranged in the carpal tunnel, superficial and deep respectively and continue distally in pairs to each finger except the thumb. They are invested by a common tendon sheath that starts proximal to the carpal tunnel and extends to within 5mm of the insertion of the profundus tendon on the distal phalanx. A separate ulnar bursa envelops the flexor tendons of the little finger (digiti minimus). The other tendon in the carpal tunnel is the flexor tendon of the thumb, flexor pollicis longus, which has a separate synovial covering the radial bursa. There is a gap between ulnar bursa and the synovial sheaths of the index, long (digiti medius), and ring (digiti anularis) fingers in the distal palm of the hand, therefore inflammation cannot spread to this 3 fingers directly from the common synovial sheath.

The flexor pollicis longus is surrounded by the radial bursa, which extends distally. The other flexor tendons are surrounded by the ulnar bursa, which extends to the little finger (digiti minimus). Note the gap between this bursa and the synovial sheaths of the 2^nd, 3^rd and 4^th fingers. The little finger will most probably be damaged.

Explanation

Defects in male genitalia:

Hypospadia: fusion of the urethral folds is incomplete and abnormal openings of the urethra occur along the inferior (undersite) surface of the penis, usually near the glans, along the shaft or near the base of the penis.

Epispadia is a rare abnormality (1/30000 births) in which the urethral meatus is found on the dorsum (superior) surface of the penis.

Explanation

Explanation

The paired palatine tonsil (tonsilla palatina) lies in the tonsillar sinus, (fossa tonsillaris) between the palatoglossal and palatopharyngeal arches (palatine arches). Palatoglossal arch (the anterior pillar of fauces), is paired running down from the soft palate to the margins of the tongue. Palatopharyngeal arch, also paired runs down from the soft palate to the lateral wall of the pharynx, ending behind the latter. Tonsillar sinus is a depression between the palatine arches, which contains the palatine tonsil.

Explanation

The inferior mesenteric artery arises from the anterior aspect of the abdominal aorta. The artery gives the branches as follows: left colic artery (arteria colica sinistra); sigmoid arteries (supplies sigmoid colon) and superior rectal artery (supplies the rectum). Left colic artery (sinister colic) ascends leftwards to supply the descending colon. On reaching the intestine, the artery gives the ascending and descending branches that anastomose with the middle colic artery and sigmoid artery.

Explanation

The pituitary gland (hypophysis) occupies the hypophysial fossa in the sella turcica of sphenoid bone. Therefore, a tumor of this gland can cause enlargement of the sellar cavity and destruction of different parts of sella turcica.

Explanation

What forms the walls of the ingunal canal:

·        Anteriorly: the aponeuroses of the external and internal oblique muscles.

·        Posteriorly: the transversalis fascia.

·        Superiorly: the arching fibers of the internal oblique and transverses abdominis muscles.

·        Inferiorly: the inguinal ligament.

Contents:

·        Men: Spermatic cord (funiculus spermaticus) and the ilioinguinal nerve

·        Women: round ligament of the uterus (ligamentum teres uteri) and the ilioinguinal nerve.

Explanation

The pyramidal fasciculus is subdivided into the corticonuclear/corticobulbar fibers and the corticospinal fibers. The fiber of the pyramidal fasciculus passes through the genu and the anterior portion of the internal capsule and descends to the brainstem and the spinal cord. The corticonuclear tract passes through the genu of the internal capsule.  The genu is situated between the anterior and posterior limbs. Lesion in genu causes alteration in motor activities in opposite side due to damage of corticonuclear/corticobulbar fibers.

Explanation

Foreign bodies inspired into the trachea are most likely to be found in the right main bronchus because it is wide and believed to be a continuation of the trachea. The superior lobe of the right lung consists of 3 segments: apical segment, posterior segment and anterior segment. A foreign body closing the right superior lobar bronchus will prevent air supply to these 3 segments listed above.

Explanation

Labia majora/labia majus (large lips of pudendum) are paired thickened skin folds covered with hair. The labia enclose the pudendal cleft and protect deeper pudendal organs. The greater vestibular glands (bartholin’s glands) are paired rounded organs in size (about 1cm wide). They reside under the perineal membrane posterior to the bulb of vestibule in the base of the labia majus laterally to the vaginal orifice. The bartholin’s gland is similar to the bulbo-urethral glands in males. They produce secretions, which moistens the vaginal inlet.

Explanation

Recurrent laryngeal nerve arises from the cervical part of the vagus nerve within the upper portion of the thoracic cavity yet its branches terminate in the cervical region. The left nerve loops around the aortic arch, the right nerve loops around the subclavian artery. Both nerves return to the cervical region where they reside between the trachea and the esophagus. The nerve comprises all types of fibers and supplies the trachea, esophagus, all laryngeal muscles (except for the cricothyroid) and the laryngeal mucosa below the rima glottidis. Injury to the recurrent laryngeal nerve results in aphonia (inability to produce voice) because of laryngeal muscles paralysis.

Explanation

Olfactory receptors (1^st order neuron) → Mitral cells (2^nd order neuron) → Olfactory tract → Olfactory trigone, anterior perforated substance, septum pellucidum (3^rd order neuron) → Uncus of parahippocampal gyrus.

The Olfactroy analyzer is one of the oldest ones so it features several fibers that take the shortest route to the Olfactory cortex i.e. do not relay within the thalamus. Therefore cutting the  thalamocortical tracts will not affect olfactory stimulus transmission to the cerebral cortex.

Thalamocortical tracts transmits all sensory information to the cerebral cortex except the Olfactory stimulus. This  tract arise from different nuclei in the thalamus (i.e. the third order neuron) and ends in the cerebral cortex.

Explanation

As far as the lungs in fetus are inactive, the pulmonary arteries receive but little blood; so the greater portion of the venous blood that enters the pulmonary trunk drains to the aorta via wide ductus arteriosus (botallo’s duct). The duct connects the bifurcation of the pulmonary trunk to the concave portion of the aortic arch. Nonclosure of ductus arteriosus – Patent ductus arteriosus: In this case, the aorta (with relatively high blood pressure maintained) shunts the blood to the pulmonary trunk via the patent ductus arteriosus. This results in pressure increase within the pulmonary route and hypertrophy of both ventricles. This excessive shunting causes blood deficiency in the descending aorta and reduced blood supply to related organs. This in turn leads to marked growth retardation in children.

Explanation

Ligamentum flava resides between the vertebral arches and consist of yellow elastic tissue. The clefts between the vertebral arches are covered by the ligamentum flava, which is the widest in the lumbar region. Therefore, these regions are used for the punctures of the vertebral canal to access the subarachnoid space. This procedure is actually performed on the L2 and L3 as well between the L3 and L4. Moreover, the puncture is also performed between the occipital bone and the first cervical vertebra piercing the atlanto-occipital membrane. In the thoracic region, the spinous processes overlap each other like a tile covering the arches of the lower vertebrae.

Explanation

From the bladder, the peritoneum passes onto the uterus to form the vesico-uterine pouch; its floor neighbors the cervix. Posteriorly, the peritoneum covers both intestinal surface and supravaginal part of cervix reaching the posterior surface of vagina. Passing onto the rectum, the peritoneum forms the rectouterine pouch (pouch of douglas). It is the deepest intraperitoneal space in both the upright and the supine position – blood, pus and other free fluids in the peritoneal cavity pool in the pouch because of its dependent location.

Explanation

The superficial veins of the lower limbs give rise to the great and small saphenous veins (vena saphena magna and parva respectively). They arise from the dorsal and plantar venous networks of foot. The small saphenous vein (vena saphena parva) arises at the lateral aspect of foot. The vein rounds the lateral malleolus and ascends along the posterior surface of leg in between the heads of the gastrocnemius muscle. At the popliteal fossa, the muscle pierces the fascia and joins the popliteal vein.

Great saphenous vein (vena saphena magna) arises from the medial portion of the dorsal venous network of foot and ascends along the medial aspect of the leg and thigh.

Explanation

There are two types of roots of spinal nerves:

·        Anterior (ventral, motor) root: it arises from the anterolateral sulcus and contains a set of axons of motor neurons located within the anterior columns; the anterior roots number 31 pairs.

·        Posterior (dorsal, sensory) root: it is a set of central processes of sensory pseudounipolar neurons located within the spinal ganglia; the posterior roots also number 31 pairs. Cutting this root will lead to loss of sensory stimulus.

Explanation

Defects in male genitalia:

Hypospadia: fusion of the urethral folds is incomplete and abnormal openings of the urethra occur along the inferior (undersite) surface of the penis, usually near the glans, along the shaft or near the base of the penis.

Epispadia is a rare abnormality (1/30000 births) in which the urethral meatus is found on the dorsum (superior) surface of the penis. (\'urethral was split\')

Explanation

The greatest branches of the lumbar plexus are the femoral and obturator nerves; others include the iliohypogastric nerve, ilioinguinal nerve, genitofemoral nerve, lateral cutaneous nerve and the muscular branches. The iliohypogastric nerve arises from behind the lateral border of the psoas major muscle and runs in between the transverses abdominis and the external oblique muscles. The nerve supplies all abdominal muscles, the skin of hypogastrium and the skin of the gluteal region (its superolateral portion).

Explanation

Trapezius is a flat, triangular muscle, whose base is facing the spinous processes of the vertebrae. It resides in the upper part of the back and the occiput. The right and left trapezius muscles together form a trapezoid.

Origin: the external occipital protuberance, the superior nuchal line, the ligamentum nuchae and the spinous processes of vertebrae C₇ - T₁₂.

Insertion: the spine of the scapula, the acromion and the lateral third of the clavicle.

Action: adducts, rotates, elevates and depresses the scapula.

Nuchal region – neck region

Explanation

Medial cutaneous nerve of arm (medial brachial cutaneous nerve) is a branch of brachial plexus from the infraclavicular part. It’s a thin nerve that arises from the medial cord of brachial plexus and supplies the skin of medial area of arm. Medial antebrachial cutaneous nerve supplies the anteromedial area of forearm.

Explanation

The Ulnar nerve arises from the medial cord of the brachial plexus. It runs along the medial bicipital groove, and proceeds to the ulnar groove situated on the posterior surface of the medial epicondyle of humerus. There the nerve runs covered by fascia and skin only.

Musculocutaneous nerve arises from the lateral cord then traverses the coracobrachialis and appears in between the biceps brachii and the brachialis muscles.

Radial nerve (nervus radialis) arises from the posterior cord of brachial plexus. It passes the radial canal along with deep artery of arm. The nerve quits the canal via its inferior opening (in between the brachialis and the brachioradialis muscle) that leads to the cubital fossa; here at the head of radius, the nerve splits into the superficial and deep branches.

Explanation

Explanation

There is a certain correlation between age of individual and thymus activity. In neonates, it already appears to have a considerable mass of 13.3g on the average. Most intensive growth occurs during first 3years of life, when the gland doubles in size. Having reached the maximum weight (about 26 – 30g), the thymus retains it until 20years of life. After 20 years of age, the thymus parenchyma experiences gradual involution and is substituted with fat tissue. After 50 years of age, the fat constitutes 90% of gland mass.

Explanation

   Flexor digitorum superficialis (superficial finger flexor) arises by two heads – the humero-ulnar head and radial head from the corresponding bones. The spindle-shaped belly of the muscle divides into 4 long tendons, which pass under the flexor retinaculum and attach to the bases of the middle phalanges of the II through V digits. Prior to this, each tendon separates into two slips and forms a cleft, which gives passage to the tendon of the flexor digitorum profundus. The flexor digitorum profundus (profound/deep finger flexor) resides in the middle of the deep layer underneath the flexor digitorum superficialis. So, a trauma of the hand will affect the superficial muscles first before the deep (profundus) muscles are affected. Therefore, superficial finger flexor is the more correct answer.

Explanation

Ileal diverticulum or Meckel’s diverticulum is a congenital anomaly that occurs in 1-2% of the population. A remnant of the proximal part of the embryonic omphaloenteric duct (yolk stalk), the diverticulum usually appears as a finger-like pouch. It is always at the site of attachment of the omphaloenteric duct on the antimesenteric border (border opposite the mesenteric attachment) of the ileum. The diverticulum is usually located 30-60cm from the ileocecal junction in infants and 50cm in adults. It may be free (74%) or attached to the umbilicus (26%). Although its mucosa is mostly ileal in type, it may also include areas of acid-producing gastric tissue, pancreatic tissue or jejuna or colonic mucosa. An ileal diverticulum may become inflamed and produce pain mimicking that produced by appendicitis.

Explanation

Ligamentum flava resides between the vertebral arches and consist of yellow elastic tissue. The clefts between the vertebral arches are covered by the ligamentum flava, which is the widest in the lumbar region. Therefore, these regions are used for the punctures of the vertebral canal to access the subarachnoid space. This procedure is actually performed on the L2 and L3 as well between the L3 and L4. Moreover, the puncture is also performed between the occipital bone and the first cervical vertebra piercing the atlanto-occipital membrane. In the thoracic region, the spinous processes overlap each other like a tile covering the arches of the lower vertebrae.

Explanation

Explanation

Explanation

The ureter connects the renal pelvis with the urinary bladder. It is 30cm long, 5-6mm in diameter and lies extraperitoneally (i.e. devoid of peritoneal investment). Each ureter has 3 parts: abdominal, pelvic and intramural parts. Entering the pelvic inlet, the right ureter crosses the right external iliac artery and the left crosses the left common iliac artery. In females, the ureters run posterior to the broad ligament of uterus and then along the free border of ovary. Laterally to the cervix of uterus, the ureters loop around the inferior border of the broad ligament cross the uterine vessels at a right angle and pass between the anterior wall of vagina and the urinary bladder to reach the fornix of the latter posteriorly.

Explanation

The anterior group of muscles of the pelvic girdle comprises the flexors, which includes the iliopsoas (iliacus and psoas major muscles) and psoas minor muscle. The iliopsoas consists of two muscles – the psoas major and iliacus. The psoas major is a thick, elongated fusiform muscle, which extends from the lumbar region downward, occupying the space between the bodies of the vertebrae and their transverse processes. The muscle becomes narrower below, and passing under the inguinal ligament, it fuses with the iliacus muscle. The psoas major is a major component of the renal bed together with other muscles such as the diaphragm, quadratus lumborum and transverse abdominis muscle.

Explanation

Lateral group of muscles of the leg have a common origin. The muscles of the lateral group (long and short peroneal muscles – peroneus longus and brevis) originate from the lateral condyle of the tibia, head and body of the fibula as well as from the deep fascia of the leg and its intermuscular septa. The peroneus longus (long peroneal muscle) resides superficially. It belongs to the pinnate muscles. In the lower third, it continues into the long tendon. The tendon descends and runs behind the lateral malleolus crossing over with the tendon of the peroneus brevis. Further, the tendon changes its direction and extends to the plantar surface of the foot. Here, it lies in the groove of the cuboid bone and runs obliquely across the foot inserting on its medial side. The peroneus brevis (short peroneal) lies underneath the peroneus longus muscle directly on the fibula. Peroneus longus (long peroneal muscle) pronates, abducts and flexes the foot.

Explanation

The muscles of the thigh are divided into the anterior, medial and posterior groups. The anterior group – flexors of the thigh; posterior group – extensors of the thigh and medial group – adductors. The quadriceps femoris is the strongest muscle of the thigh, which occupies the entire anterior, lateral and partially medial surfaces of the thigh. It consists of four heads: rectus femoris, vastus medialis, vastus intermedius and vastus lateralis. All four heads of the quadriceps femoris in the lower part of the thigh fuse together and continue as a common tendon. This muscle acts on the hip joint and participates in the flexion of the thigh; it is also a powerful extensor of the leg at the knee joint. It is supplied by the femoral nerve.

Explanation

For temporary control of hemorrhage by digital (finger) pressing, press on the artery at the sites where it lies superficially and around a bone:

·        Carotid artery: transverse process of the C₆ vertebra

·        Subclavian artery: first rib

·        Brachial artery: internal surface of the humerus

·        Femoral artery: pubic bone

Explanation

The anterior group of muscles of the leg (crus – leg): tibialis anterior, extensor digitorum longus, extensor hallucis longus. They have a common origin which is the lateral condyle of the tibia, both bones of the leg, their interosseus membrane as well as from the deep fascia of the leg. The tibialis anterior muscle lies superficially. In the upper part, it has a fleshy muscular part, which continues into the long flat tendon in the lower third of the leg. The tendon bends medially and attaches to the bones on the plantar surface of the medial side of the foot. It dorsiflexes (dorsal flexion) the foot at the ankle and inverts the foot (supinate the foot). Function of tibialis anterior muscle is disturbed if the dorsal flexion of foot is hindered.

Explanation

The middle ear comprises the tympanic cavity with the auditory ossicles and the pharyngotympanic (auditory or eustachian) tube. The auditory tube communicates the tympanic cavity with the nasopharynx. The tube runs inferiorly and medially; it is 3.5cm long and 2mm wide. The tube features the bony and cartilaginous parts. The tube has two openings called the tympanic opening and the pharyngeal opening. Infectious agents can get into the middle ear from the pharynx through this tube and cause complications like otitis media.

Explanation

The muscles of the thigh are divided into the anterior, medial and posterior groups. The anterior group – flexors of the thigh; posterior group – extensors of the thigh and medial group – adductors. The quadriceps femoris is the strongest muscle of the thigh, which occupies the entire anterior, lateral and partially medial surfaces of the thigh. It consists of four heads: rectus femoris, vastus medialis, vastus intermedius and vastus lateralis. All four heads of the quadriceps femoris in the lower part of the thigh fuse together and continue as a common tendon. This muscle acts on the hip joint and participates in the flexion of the thigh; it is also a powerful extensor of the leg at the knee joint. It is supplied by the femoral nerve.

Explanation

The emissary veins communicate the dural venous sinuses with the extrinsic veins of head. They pass within the respective cranial canals. The largest emissary veins are parietal, mastoid, condylar and occipital emissary veins. The mastoid emissary vein (vena emissaria mastoidea) passes within the mastoid foramen. It communicates the transverse sinus with the occipital vein.

Explanation

The lesser omentum is the residue of dorsal mesentery of stomach and duodenum. It consists of two main ligaments: hepatogastric and hepatoduodenal ligaments. Others are hepatophrenic , hepatoesophageal and hepatocolic ligaments.

·        Hepatogastric ligament (ligamentum hepatogastricum) is a double layer of peritoneum running from the porta hepatica to the lesser curvature.

·        Hepatoduodenal ligament (ligamentum hepatoduodenale) running from the porta hepatica to the superior part of the duodenum. It also consists of double layer of peritoneum and enfolds the hepatic portal vein, hepatic artery proper and common bile duct.

Explanation

The deep palmar arch (arcus Palmaris profundus) is formed by the terminal portion of radial artery and the deep palmar branch of the ulnar artery. The arch resides deep below the tendons of flexors of fingers on the bases of metacarpal bones. The deep palmar arch gives 3 palmar metacarpal arteries; they run along the interosseous muscles to reach the common palmar digital arteries (around the bases of proximal phalanges). Apart from this, they anastomose with the dorsal metacarpal arteries by means of perforating branches. The deep palmar arch can normalize blood flow to the hand in the absence of the superficial palmar arch (superficial blood vessels).