Clinical Concepts PDF

Understand first, then memorize and apply 100 must important GA conceptions Dr. Mavrych, MD, PhD, DSc Professor of Gross anatomy, SMU Dr. Mavrych, MD, PhD, DSc [email protected].. A !...

Understand first, then memorize and apply 100 must important GA conceptions Dr. Mavrych, MD, PhD, DSc Professor of Gross anatomy, SMU Dr. Mavrych, MD, PhD, DSc [email protected].. A ! ¤. ! A ¤ ! A ! ¤..! ¤ A Dr. Mavrych, MD, PhD, DSc [email protected]  1. Lumbar puncture (tap) and Epidural anesthesia When a lumbar puncture is performed, the needle enters the subarachnoid space to extract cerebrospinal fluid (spinal tap) or to inject anesthetic (spinal block) or contrast material. The needle is usually inserted between L3/L4 or L4/L5. Level of horizontal line through upper points of iliac crests. Remember, the spinal cord may end as low as L2 in adults and does end at L3 in young children and dural sac extends caudally to level of S2. Before the procedure, the patient should be examined for signs of increased intracranial pressure because cerebellar tonsils may herniate through the foramen magnum. Dr. Mavrych, MD, PhD, DSc [email protected] Dr. Mavrych, MD, PhD, DSc [email protected]  2. Herniated IV disc Herniated discs usually occur in lumbar (L4/L5 or L5/S1) or cervical regions (C5/C6 or C6/C7) of individuals younger than age 50. Herniations may follow degenerative changes in the anulus fibrosus and be caused by sudden compression of the nucleus pulposus. Herniated lumbar discs usually involve the nerve root one number below - traversing root (e.g., the herniation L4/L5 will compress L5 root). Dr. Mavrych, MD, PhD, DSc [email protected]  3. Abnormal curvatures of the spine Kyphosis is an exaggeration of the thoracic curvature that may occur in elderly persons as a result of osteoporosis (multiply compression fracture of vertebral bodies) or disk degeneration. Lordosis is an exaggeration of the lumbar curvature that may be temporary and occurs as a result of pregnancy, spondylolisthesis or potbelly. Scoliosis is a complex lateral deviation, or torsion, that is caused by poliomyelitis, a leg- length discrepancy, or hip disease. Dr. Mavrych, MD, PhD, DSc [email protected]  4. Upper limb fractures: Humerus fractures Ar BID longershorter Sites of potential injury to major nerves in fractures of the humerus: 1. Axillary nerve and posterior humeral circumflex artery at the surgical neck. 2. Radial nerve and profunda brachii artery at midshaft. 3. Brachial artery and median nerve at the supracondylar region. 4. Ulnar nerve at the medial epicondyle. Dr. Mavrych, MD, PhD, DSc [email protected]  Fracture of distal radius: Transverse fracture within the distal 2 cm of the radius. Most common fracture of the forearm (after 50). Smith's fracture results from a fall or a blow on the dorsal aspect of the flexed wrist and produces a ventral angulation of the wrist. The distal fragment of the radius is ANTERIORLY displaced. Colles' fracture results from forced extension of the hand, usually as a result of trying to ease a fall by outstretching the upper limb. Distal fragment is displaced DORSALLY - “dinner fork deformity”. colles x CollieDogDorsalAngulation Often the ulnar styloid process is avulced (broken off) Dr. Mavrych, MD, PhD, DSc [email protected]  Scaphoid fracture Occurs as a result of a fall onto the palm when the hand is abducted Pain occurs primarily on the lateral side of the wrist, especially during wrist extension and abduction Scaphoid fracture may not show on X-ray films for 2 to 3 weeks, but a deep tenderness will be present in the anatomical snuffbox. The proximal fragment may undergo avascular necrosis because the blood supply is interrupted. Dr. Mavrych, MD, PhD, DSc [email protected]  Boxer’s fracture Necks of the metacarpal bones are frequently fractured during fistfights. Typically, fractured 2d and 3d metacarpals are seen in professional boxers, and fractured 5th and sometimes 4th metacarpals are seen in unskilled fighters. Dr. Mavrych, MD, PhD, DSc [email protected]  5 Rotator cuff muscles – SITS Support the shoulder joint by forming a musculotendinous rotator cuff around it Reinforces joint on all sides except inferiorly, where dislocation is most likely Rotator cuff muscles are Supraspinatus, Infraspinatus, Teres minor, Subscapularis: SITS. Right humerus Dr. Mavrych, MD, PhD, DSc [email protected]  6. Abduction of the upper limb (0°-15°) Abduction of the upper extremity is initiated by the supraspinatus muscle (suprascapular nerve). (15°-110º) Further abduction to the horizontal position is a function of the deltoid muscle (axillary nerve). (110°-180°) Raising the extremity above the horizontal position requires scapular rotation by action of the trapezius (accessory nerve CNXI) and serratus anterior (long thoracic nerve). Dr. Mavrych, MD, PhD, DSc [email protected]  Subacromial bursitis Subacromial bursitis (influmution of the subacromial bursa) is often due to calcific supraspinatus tendinitis, causing a painful arc of of abduction. Dr. Mavrych, MD, PhD, DSc [email protected]  7. Medial (golfer’s elbow) and lateral (tennis elbow) epicondylitis Medial epicondylitis is inflammation of the common flexor tendon of the wrist where it originates on the medial epicondyle of the humerus. Lateral epicondylitis: repeated forceful flexion and extension of the wrist resulting strain attachment of common extensor tendon and inflammation of periosteum of lateral epicondyle. Pain felt over lateral epicondyle and radiates down posterior aspect of forearm. Pain often felt when opening a door or lifting a glass CatereallyLovesTennis Dr. Mavrych, MD, PhD, DSc [email protected]  8. Arterial anastomoses around the scapula Blockage of the Subclavian or Axillary artery can be bypassed by anastomoses between branches of the Thyrocervical and Subscapular arteries: Transverse cervical Suprascapular Subscapular Circumflex scapular Dr. Mavrych, MD, PhD, DSc [email protected]  9. Cubital fossa Contents from lateral to medial: 1. Biceps brachii tendon 2. Brachial artery 3. Median nerve Subcutaneos structures from lateral to medial: 1. Cephalic vein 2. Median cubital vein: joins cephalic and basilic veins 3. Basilic vein Sites of venipuncture is usually median cubital vein because: Overlies bicipital aponeurosis, so deep structure protected Not accompanied by nerves Dr. Mavrych, MD, PhD, DSc [email protected]  10. Carpal Tunnel Syndrome Results from a lesion that reduces the size of the carpal tunnel (fluid retention, infection, dislocation of lunate bone) Median nerve – most sensitive structure in the carpal tunnel and is the most affected Clinical manifestations: Pins and needles or anesthesia of the lateral 3.5 digits palm sensation is not affected because superficial palmar cutaneous branch passes superficially to carpal tunnel Apehand deformity - absent of OPPOSITION Dr. Mavrych, MD, PhD, DSc [email protected]  11. Test of the proximal and distal interphalangeal joints PIP – FDS DID - FDP Dr. Mavrych, MD, PhD, DSc [email protected]  12. Lesion of UL nerves Upper Brachial Palsy Injury of upper roots and trunk Usually results from excessive increase in the angle between the neck and the shoulder stretching or tearing of the superior parts of the brachial plexus (C5 and C6 roots or superior trunk) May occur as birth injury from forceful pulling on infant's head during difficult delivery Dr. Mavrych, MD, PhD, DSc [email protected]  Upper Brachial Palsy (Erb-Duchenne palsy) In all cases, paralysis of the muscles of the shoulder and arm supplied by C5 and C6 spinal nerves (roots) of the upper trunk. Combination lesions of axillary, suprascapular and musculocutaneous nerves with loss of the shoulder mm and anterior arm. As result patient have “waiter’s tip” hand: adducted shoulder medially rotated arm extended elbow loss of sensation in the lateral aspect of the upper limb Dr. Mavrych, MD, PhD, DSc [email protected]  Lower Brachial Palsy (Klumpke paralysis) Injury of lower roots and trunk May occur when the upper limb is suddenly pulled superiorly: stretching or tearing of the inferior parts of the brachial plexus (C8 and T1 roots or inferior trunk) E.g., grabbing support during fall from height or as a birth injury, or TOS – thoracic outlet syndrome Dr. Mavrych, MD, PhD, DSc [email protected]  Lower Brachial Palsy (Klumpke paralysis) All intrinsic muscles of the hand supplied by the C8 and T1 roots of the lower trunk affected. Combination lesions of ulnar nerve (“claw hand”) and median nerve (“ape hand”) Loss of sensation in the medial aspect of the upper limb and medial 1,5 fingers. May include a Horner syndrome Dr. Mavrych, MD, PhD, DSc [email protected]  Injury to musculocutaneous nerve Usually results from lesions of lateral cord Greatly weakens flexion of elbow (biceps and brachialis muscles) and supination of forearm (biceps muscle) May be accompanied by anesthesia over lateral aspect of forearm Dr. Mavrych, MD, PhD, DSc [email protected]  Cutaneous innervation of the hand Dorsum: 1,5-U and 3,5 R Palm: 1,5-U and 3,5 M Dr. Mavrych, MD, PhD, DSc [email protected]  13. Avascular necrosis of femoral head A common fracture in elderly women with osteoporosis is fracture of the femoral neck. Transcervical fracture disrupts blood supply to the head of the femur via retinacular arteries (from medial circumflex femoral artery) and may cause avascular necrosis of the femoral head if blood supply through the ligament to the head is inadequate. Dr. Mavrych, MD, PhD, DSc [email protected]  14. Knee joint injury: Unhappy triad Because the lateral side of the knee is struck more often (e.g., in a football tackle), the tibial collateral ligament is the most frequently torn ligament at the knee. The unhappy triad of athletic knee injuries involves: 1. Tibial collateral ligament 2. Medial meniscus 3. Anterior cruciate ligament Dr. Mavrych, MD, PhD, DSc [email protected]  Fibular collateral ligament (lateral collateral ligament) Rounded cord between lateral epicondyle of femur and head of fibula Does NOT blend with joint capsule and does NOT attach to lateral meniscus Limits extension and adduction of leg at knee Dr. Mavrych, MD, PhD, DSc [email protected]  Rupture of the cruciate ligaments With rupture of the anterior cruciate ligament, the tibia can be pulled forward excessively on the femur, exhibiting anterior drawer sign. In the less common rupture of the posterior cruciate ligament, the tibia can be pulled backward excessively on the femur, exhibiting posterior drawer sign. Dr. Mavrych, MD, PhD, DSc [email protected]  Prepatellar bursa Suprapatellar bursa Prepatellar bursa: between superficial surface of patella and skin. May become inflamed and swollen (prepatellar bursitis) Suprapatellar bursa: superior extension of synovial cavity between distal end of femur and quadriceps muscle and tendon. Usual place for intra- articular injections Dr. Mavrych, MD, PhD, DSc [email protected]  Knee jerk reflex The patellar reflex is tested by tapping the patellar ligament with a reflex hammer to elicit extension at the knee joint. Both afferent and efferent limbs of the reflex arch are in the femoral nerve (L2-L4). Knee jerk reflex: tests spinal nerves L2-L4. Dr. Mavrych, MD, PhD, DSc [email protected]  15. Ankle joint injury: Ankle sprains Sprains are the most common ankle injuries A sprained ankle is nearly always an inversion injury, involving twisting of the weight-bearing plantarflexed foot. The lateral ligament (anterior talofibular ligament) is injured because it is much weaker than the medial ligament. In severe sprains, the lateral malleolus of the fibula may be fractured. Dr. Mavrych, MD, PhD, DSc [email protected]  Pott’s fracture Fracture-dislocations of the ankle (Pott's fracture): Forced eversion (abduction) of the foot The medial ligament avulses the medial malleolus or the medial ligament tears, and fibula fractures at a higher level Forced inversion (adduction) avulses the lateral malleolus of fibula or tears the lateral ligament Pott's fracture Dr. Mavrych, MD, PhD, DSc [email protected]  Ankle jerk reflex Achilles tendon reflex is tested by tapping the calcaneal tendon to elicit plantar flexion at the ankle joint. Both afferent and efferent limbs of the reflex arc are carried in the tibial nerve (S1, S2). Ankle jerk reflex: tests spinal nerves S1-S2. Dr. Mavrych, MD, PhD, DSc [email protected]  16. Injury of the gluteal region: Piriformis syndrome Inflammation or spasm of the piriformis muscle may produce pain similar to that caused by sciatica ("piriformis syndrome"). Piriformis “Landmark” of the gluteal region: provides key to understanding relationships in the gluteal region; determines names of blood vessels and nerves action: supination of hip joint Dr. Mavrych, MD, PhD, DSc [email protected]  Injury to sciatic nerve Weakened hip extension and knee flexion Footdrop (lack of dorsiflexion) Flail foot (lack of both dorsiflexion and plantar flexion) Cause of injury: caused by improperly placed gluteal injections but may result from posterior hip dislocation Dr. Mavrych, MD, PhD, DSc [email protected]  Superior gluteal nerve injury The superior gluteal nerve may be injured during surgery, posterior dislocation of the hip or poliomyelitis. Paralysis of the gluteus medius and gluteus minimus muscles occurs so that the ability to pull the pelvis up and abduction of the thigh are lost. If the superior gluteal nerve on the left side is injured, the right pelvis falls downward when the Superior gluteal patient raises the right foot off the nerve injury ground. Note that it is the side contralateral to the nerve injury that is affected. Dr. Mavrych, MD, PhD, DSc [email protected]  Injury to inferior gluteal nerve Weakened hip extension (gluteus maximus), most noticeable when climbing stairs or standing from a seated position Cause of injury: posterior hip dislocation, surgery in this region Dr. Mavrych, MD, PhD, DSc [email protected]  17. Avulsion fractures of the hip bone and hamstrings muscles Avulsion fractures occur where muscles are attached - ischial tuberosities Hamstrings muscles: 1. Biceps femoris 2. Semitendinosus 3. Semimembranosus Action: extension of hip joint and flexion of knee joint Nerve supply – Tibial nerve (short head of biceps femoris is supplied by the common fibular nerve) Dr. Mavrych, MD, PhD, DSc [email protected]  18. Femoral sheath & femoral hernia Extension of transversalis fascia and iliacus fascia that enters thigh deep to inguinal ligament Divided into three compartments from lateral to medial enclosing: Femoral artery Femoral vein Femoral canal Dr. Mavrych, MD, PhD, DSc [email protected]  Femoral hernia Inguinal lig. A femoral hernia passes through the femoral ring into the femoral canal to form a swelling in the upper thigh inferior and lateral to the pubic tubercle The hernial sac may protrude through the saphenous hiatus into the superficial fascia A femoral hernia occurs more frequently in females and is dangerous because the hernial sac may become strangulated An aberrant obturator artery is vulnerable during surgical repair Dr. Mavrych, MD, PhD, DSc [email protected]  19. Rupture of the Achilles tendon and Triceps surae muscle Avulsion or rupture of the calcaneal (Achilles) tendon disables the triceps sure muscle (gastrocnemius & soleus) so that the patient cannot plantar flex the foot. Triceps surae muscle: 2 Heads of Gastrocnemius m. 1 Head - Soleus muscle Plantaris small fusiform belly with long thin tendon; may be absent sometimes may become hypertrophy Dr. Mavrych, MD, PhD, DSc [email protected]  Injury to tibial nerve In popliteal fossa: loss of plantar flexion of foot (mainly gastrocnernius and soleus muscles) and weakened inversion (tibialis posterior muscle), causing calcaneovalgus. Inability to stand on toes Dr. Mavrych, MD, PhD, DSc [email protected]  20. Fracture of the fibular neck May cause an injury to the common peroneal nerve, which winds laterally around the neck of the fibula. This injury results in paralysis of all muscles in the anterior and lateral compartments of the leg (dorsiflexors and evertors of the foot) Causing foot drop. Dr. Mavrych, MD, PhD, DSc [email protected]  21. Breast: Carcinoma of the Breast Carcinomas of the breast are malignant tumors, usually adenocarcinomas arising from the epithelial cells of the lactiferous ducts in the mammary gland lobules 1. It enlarges, attaches to suspensory (Cooper‘s) ligaments, and produces shortening of the ligaments, causing depression or dimpling of the overlying skin. Dr. Mavrych, MD, PhD, DSc [email protected]  Lymphatic drainage of the breast It is important because of its role in the metastasis of cancer cells. Most lymph (> 75%), especially from the lateral breast quadrants, drains to the axillary lymph nodes, initially to the anterior (pectoral) nodes for the most part. Most of the remaining lymph, particularly from the medial breast quadrants, drains to the parasternal lymph 75% 25% nodes or to the opposite breast. Dr. Mavrych, MD, PhD, DSc [email protected]  Mastectomy Radical mastectomy, a more extensive surgical procedure, involves removal of the breast, pectoral muscles, fat, fascia, and as many lymph nodes as possible in the axilla and pectoral region. During a radical mastectomy, the long thoracic nerve may be lesioned during ligation of the lateral thoracic artery. A few weeks after surgery, the female may present with a winged scapula and weakness in abduction of the arm above 90° because serratus anterior m. paralysis. The intercostobrachial nerve may also be damaged during mastectomy, resulting in numbness of the skin of the medial arm. Dr. Mavrych, MD, PhD, DSc [email protected]  Breast infection Mastitis is an infection of the tissue of the breast that occurs most frequently during the time of breastfeeding (1 to 3months after the delivery of a baby). This infection causes pain, swelling, redness, and increased temperature of the breast. It can occur when bacteria, often from the baby's mouth, enter a milk duct through a crack in the nipple. It can occur in women who have not recently delivered as well as in women after menopause. Dr. Mavrych, MD, PhD, DSc [email protected]  68. Foramina of the base of the skull Dr. Mavrych, MD, PhD, DSc [email protected]  Exit of cranial nerves Dr. Mavrych, MD, PhD, DSc [email protected]  69. Fracture of the anterior cranial fossa Fracture of the anterior cranial fossa (cribriform plate of the Ethmoid bone) is suggested by anosmia, periorbital bruising (raccoon eyes), and CSF leakage from the nose (rhinorrhea). Dr. Mavrych, MD, PhD, DSc [email protected]  70. Development of skull Sutures of neurocranium Coronal suture: lies between the frontal bone and the two parietal bones. Sagittal suture: lies between the two parietal bones. Squamous suture: lies between the parietal bone and the squamous part of the temporal bone. Lambdoid suture: lies between the two parietal bones and the occipital bone. Dr. Mavrych, MD, PhD, DSc [email protected]  Cranial Malformations [A] Scaphocephaly: premature closure of the sagittal suture, in which the anterior fontanelle is small or absent, results in a long, narrow, wedge-shaped cranium. [C] Oxycephaly: premature closure of the coronal suture results in a high, tower-like cranium. When premature closure of the coronal or the lambdoid suture occurs on one side only, the cranium is twisted and asymmetrical, a condition known as plagiocephaly [B]. Dr. Mavrych, MD, PhD, DSc [email protected]  Fontanelles Anterior fontanelle present at birth; closes at age 9 to 18 months diminished size or absence at birth may indicate craniosynostosis or microcephaly. Posterior fontanelle present at birth; usually closes by age 2 months Persistence suggests underlying hydrocephalus or congenital hypothyroidism. Dr. Mavrych, MD, PhD, DSc [email protected]  74. Epidural hematoma Skull fracture near pterion often causes epidural hematoma from torn middle meningeal artery. Unconsciousness and death are rapid because the bleeding dissects a wide space as it strips the dura from the inner surface of the skull, which puts pressure on the brain. An epidural hematoma forms a characteristic biconvex pattern on computed tomography images. Dr. Mavrych, MD, PhD, DSc [email protected]  75. Infection of the Cavernous sinus Lateral to body of sphenoid bone and sella turcica, forming lateral wall of hypophyseal fossa Related structures: Structures that pass through sinus: 1. Internal carotid artery and internal carotid plexus 2. Abducens nerve (CN VI) Structures on lateral wall of sinus: 1. Oculomotor nerve (CN III) 2. Trochlear nerve (CN IV) Dr. Mavrych, MD, PhD, DSc [email protected]  Ophthalmic Veins Superior ophthalmic vein – communicates anteriorly with the facial (angular) vein Inferior ophthalmic vein – communicates through the inferior orbital fissure with the pterygoid plexus of veins Both veins pass posteriorly through the superior orbital fissure and drain into the Cavernous sinus Dr. Mavrych, MD, PhD, DSc [email protected]  76. Layers of the scalp 1. Skin - contains numerous sweat glands, sebaceous glands, and hair follicles 2. Connective tissue- Dense superficial fascia containing nerves and blood vessels 3. Aponeurosis (Epicranial) -Fibrous epicranial aponeurosis connecting frontalis and occipitalis parts of occipitofrontalis muscle 4. Loose areolar tissue -Allows 3 more superficial layers to move over skull surface; somewhat like a sponge because it contains innumerable potential spaces capable of being distended with fluid resulting from injury or infection 5. Pericranium -periosteum covering the outer surface of the skull bones Dr. Mavrych, MD, PhD, DSc [email protected]  77. Innervation skin of the face Skin of face supplied by branches of the three divisions of the TRIGEMINAL NERVE (CN V) 1 Except for a small area over the angle of the mandible which is supplied by the great auricular nerve (C2-C3) – cervical plexus 2 Dr. Mavrych, MD, PhD, DSc [email protected]  78. Facial nerve (CN VII) FACIAL NERVE (CN VII) - sole motor supply to the muscles of facial expression and certain other muscles derived from the embryonic 2nd pharyngeal arch Sensory to the taste buds in anterior 2/3 of the tongue through the chorda tympani Secretomotor (parasympathetic) to the submandibular, sublingual, palatine salivary glands, glands of nasal cavity and lacrimal gland Dr. Mavrych, MD, PhD, DSc [email protected]  Bell's palsy It is idiopathic unilateral facial paralysis (constitutes 75% of all facial nerve lesions) Terminal branches of CN VII may be injured by parotid cancer or by surgery to remove a parotid tumor. An infant's facial nerve may be injured during a forceps delivery because the mastoid process has not yet developed and the stylomastoid foramen is relatively superficial. Dr. Mavrych, MD, PhD, DSc [email protected]  Lesions of CN VII Symptoms associated with lesions of CN VII are determined by the location of the lesion in the nerve. Bels Manifestations: unable to close lips and eyelids on affected side eye on affected side is not lubricated (dry eye) unable to whistle, blow a wind instrument, or chew effectively facial distortion due to contractions of unopposed contralateral facial muscles A lesion within the facial canal will also affect taste from the anterior 2/3 of the tongue carried by the chorda tympani and loss of secretion from submandibular and sublingual glands ipsilateral to the lesion Dr. Mavrych, MD, PhD, DSc [email protected]  79. Communication of the paranasal sinuses Sphenoethmoidal recess receives the opening of the sphenoidal air sinus Superior meatus Receives opening of posterior ethmoidal air cells Middle meatus Infundibulum, ethmoidal bulla and semilunar hiatus Receives openings of frontal and maxillary sinuses and anterior and middle ethmoidal air cells Inferior meatus Receives opening of nasolacrimal duct Dr. Mavrych, MD, PhD, DSc [email protected]  80. Epistaxis Epistaxis (nosebleed) most often occurs from the anterior nasal septum (Kiesselbach's area), where branches of the sphenopalatine, anterior ethmoidal, greater palatine, and superior labial (from facial) arteries converge. Dr. Mavrych, MD, PhD, DSc [email protected]  81. Sphenoiditis Relationships of the sphenoidal sinus are clinically important ; because of potential injury during pituitary surgery and the possible spread of infection. Infection can reach the sinuses through their ostia from the nasal cavity or through their floor from the nasopharynx. Infection may erode the walls to reach the cavernous sinuses, pituitary gland, optic nerves, or optic chiasma Dr. Mavrych, MD, PhD, DSc [email protected]  82. Cheeks Form the lateral, movable walls of the oral cavity and the zygomatic prominences of the cheeks over the zygomatic bones Buccinator – principal muscle of the cheek Buccal pad of fat – encapsulated collection of fat superficial to buccinator Parotid duct opens in inner surface of the cheek right opposite 2nd upper molar tooth Dr. Mavrych, MD, PhD, DSc [email protected]  83. Movements at the TMJs All 4 muscles of mastication are innervated by V3: 1. Temporalis – elevation & retraction 2. Masseter - elevation 3. Medial pterygoid - elevation 4. Lateral pterygoid - protrusion Dr. Mavrych, MD, PhD, DSc [email protected]  84. Lesion of CN XII A lesion of CN XII allows the contralateral, unparalyzed genioglossus muscle to pull the protruded tongue toward the paralyzed side (deviation of the tongue). Dr. Mavrych, MD, PhD, DSc [email protected]  83. Gag reflex Touching the posterior part of the pharynx results in muscular contraction of each side of the pharynx - gag reflex: Afferent limb: CN IX Efferent limb: CN X Injury to the glossopharyngeal nerve (CN IX) will result in a negative gag reflex Dr. Mavrych, MD, PhD, DSc [email protected]  84. Tonsillitis During palatine tonsillectomy, the peritonsillar space facilitates tonsil removal, except after capsular adhesion to the superior constrictor. If the glossopharyngeal nerve is injured, taste and general sensation from the posterior 1/3 of the tongue are lost. Hemorrhage may occur, usually from the tonsillar branch of the facial artery; if the superior constrictor is penetrated, a high facial artery or tortuous internal carotid artery may be injured. Dr. Mavrych, MD, PhD, DSc [email protected]  Palatine tonsils Receives main blood supply from tonsillar branch of facial artery Drained by lymph vessels mainly to jugulodigastric lymph node, which is body's most frequently enlarged lymph node Nerve supply: tonsillar plexus of nerves formed by branches of CN IX and CN X Dr. Mavrych, MD, PhD, DSc [email protected]  85. Lymph drainage from face structures Submandibular lymph nodes receive lymph from: front of scalp nose and adjacent cheek upper lip and lower lip (except central part*) frontal, maxillary, and ethmoid air sinuses upper and lower teeth (except lower incisors*) anterior 2/3 of tongue (except tip*) After submandibular & submental → floor of mouth ,gums and drain lymph to Deep cervical vestibule *to Submental lymph nodes Dr. Mavrych, MD, PhD, DSc [email protected]  86. Blow-out fracture A blow-out fracture of the orbital floor typically is not involve the orbital rim and is caused by blunt trauma to the orbital contents (e.g., by a handball). Blow-out fractures may damage: inferior rectus muscle, infraorbital nerve and artery (hemorrhaging). Blow-out fractures are rare in young children because the maxillary sinus is small and the orbital floor is not a weak point. Dr. Mavrych, MD, PhD, DSc [email protected]  87. Muscles of the orbit Muscle Action Innerva- tion Superior rectus Elevates and adducts CN III pupil Inferior rectus Depresses and adducts CN III pupil Medial rectus Adducts pupil CN III Lateral rectus Abducts pupil CN VI Superior oblique Depresses and abducts CN IV pupil Inferior oblique Elevates and abducts CN III pupil Levator pulpebra superior Elevates upper eyelid CN III Dr. Mavrych, MD, PhD, DSc [email protected]  Clinical Testing Actions of Extraocular Muscles Medial rectus – ask the patient to look directly medially Lateral rectus – ask the patient to look directly laterally Superior rectus – ask the patient to look laterally, then superiorly Inferior rectus – ask the patient to look laterally, then inferiorly Superior oblique – ask the patient to look medially, then inferiorly Inferior oblique – ask the patient to look medially, then superiorly testing for eye movements where the single action of each muscle predominates Dr. Mavrych, MD, PhD, DSc [email protected]  88. Oculomotor Nerve Palsy (external squint) It affects most of the extraocular muscles Manifestations: ptosis, fully dilated pupil, and eye is fully depressed and abducted (“down and out”) due to unopposed actions of superior oblique and lateral rectus, respectively. Dr. Mavrych, MD, PhD, DSc [email protected]  89. Trochlear Nerve Palsy Lesions of this nerve or its nucleus cause paralysis of the superior oblique and impair the ability to turn the affected eyeball infero-medially (pupil look superio-laterally) The characteristic sign of trochlear nerve injury is diplopia (double vision) when looking down (e.g., when going down stairs) The person can compensate for the diplopia by inclining the head anteriorly and laterally toward the side of the normal eye. Dr. Mavrych, MD, PhD, DSc [email protected]  90. Abducens Nerve Palsy (internal squint) Injury to abducens nerve → paralysis of lateral rectus → inability to abduct the affected eye Affected eye is fully adducted by the unopposed action of the medial rectus that is supplied by CN III Dr. Mavrych, MD, PhD, DSc [email protected]  91. Corneal reflex Corneal reflex (blinking) in response to touching the cornea It involves reflex connections between sensory afferent fibers in the ophthalmic nerve (CN V1) that make synaptic connections with motor fibers of facial nerve (CN VII) which supply orbicularis oculis muscle. Dr. Mavrych, MD, PhD, DSc [email protected]  92. Horner syndrome Penetrating injury to the neck, Pancoast tumor, or thyroid carcinoma may cause Horner syndrome by interrupting ascending preganglionic sympathetic fibers anywhere between their origin in the upper thoracic spinal cord and their synapse in the superior cervical ganglion. It includes the following signs: Constriction of the pupil (miosis) Drooping of the superior eyelid (ptosis), Redness and increased temperature of the skin (vasodilation) Absence of sweating (anhydrosis) Dr. Mavrych, MD, PhD, DSc [email protected]  93. Otitis Media Hearing is diminished because of pressure on the eardrum and reduced movement of the ossicles. Taste may be altered because the chorda tympani is affected. Infection spreading posteriorly cause mastoiditis. Infection that spreads to the middle cranial fossa can cause meningitis or temporal lobe abscess, and infection moving through the floor may produce sigmoid sinus thrombosis. Dr. Mavrych, MD, PhD, DSc [email protected]  Perforation of the Tympanic Membrane May result from otitis media and is one of several causes of middle ear (conduction) deafness Causes: foreign bodies in external acoustic meatus, excessive pressure (as in diving), trauma Because chorda tympani directly relates to the posterior surface of the tympanic membrane it may be damaged and resulting in loss of taste over anterior 2/3 of the tongue and secretion of the sublingual and submandibular glands Minor perforation heal spontaneously; large ones require surgical repair Dr. Mavrych, MD, PhD, DSc [email protected]  94. Thyroid and parathyroid glands Hormones: The thyroid gland is the body's largest endocrine gland. It produces thyroid hormone, which controls the rate of metabolism (increase the temperature of the body), and calcitonin, a hormone controlling calcium metabolism (reduce blood calcium Ca2+). The thyroid gland affects all areas of the body except itself and the spleen, testes, and uterus. The hormone produced by the parathyroid glands, parathormone (PTH), controls the metabolism of phosphorus and calcium in the blood (increase Ca2+ level). The parathyroid glands target the skeleton, kidneys, and intestine. Dr. Mavrych, MD, PhD, DSc [email protected]  Anatomical relations of the thyroid gland Anterolateral – infrahyoid muscles 1 Posterolateral – common carotid artery Medial – larynx, trachea , pharynx, esophagus, cricothyroid muscle, recurrent laryngeal 1 nerve Posterior – parathyroid glands 1 3 Dr. Mavrych, MD, PhD, DSc [email protected]  Median cervical cyst Usually presents as a painless midline mass on the anterior aspect of the neck at the level of the hyoid bone and moves during swallowing. Remanent of the thyroglossal canal (thyroid gland originally from epithelium of the tongue). Must be differentiated from a thyroid mass Treatment: surgical excision Dr. Mavrych, MD, PhD, DSc [email protected]  Variation of parathyroid glands position The superior parathyroid glands, more constant in position than the inferior ones. The inferior parathyroid glands are usually near the inferior poles of the thyroid gland, but they may lie in various positions In 1-5% of people, an inferior parathyroid gland is deep in the superior mediastinum within the thymus because of common embryonic origin. Dr. Mavrych, MD, PhD, DSc [email protected]  95. Larynx: Cavity of the Larynx - 2 Folds: Vestibular folds (false vocal cords) Vocal folds (true vocal cords) Rima vestibuli – gap between the vestibular folds Rima glottidis – gap between the vocal folds anteriorly and vocal processes of the arytenoid cartilages posteriorly Dr. Mavrych, MD, PhD, DSc [email protected]  Muscles of the Larynx Abductors Posterior cricoarytenoid – abducts vocal folds (the only abductors of the vocal folds) Dr. Mavrych, MD, PhD, DSc [email protected]  Vagus Nerve (CN X) Superior laryngeal nerve: divides into internal and external laryngeal nerves Internal laryngeal nerve – sensory; supplies floor of piriform recess and mucous membrane of larynx above of the vocal folds External laryngeal nerve – motor; supplies the cricothyroid muscle Dr. Mavrych, MD, PhD, DSc [email protected]  Vagus Nerve (CN X) Recurrent laryngeal nerve: supplies all muscles of larynx, except cricothyroid; mucous membrane of larynx below vocal fold; mucous membrane of upper trachea right recurrent laryngeal nerve → hooks around the right subclavian artery left recurrent laryngeal nerve → hooks around the arch of the aorta posterior to the ligamentum arteriosum ascends in the neck in a groove between the trachea and esophagus Dr. Mavrych, MD, PhD, DSc [email protected]  96. Cricothyrotomy A cricothyrotomy is an emergency procedure that relieves an airway obstruction. In case of swallowed foreign bodies or abnormal tissue growths. A hollow needle is inserted into the midline of the neck, just below the thyroid cartilage (needle cricothyrotomy). More frequently, a small incision is made in the skin over the cricothyroid membrane, and another one is made through the membrane between the cricoid and thyroid cartilage. A tube that enables breathing is inserted through the incision. Cricothyrotomy is generally followed by a surgical tracheosotomy, if there is need for a prolonged use of a breathing tube. Dr. Mavrych, MD, PhD, DSc [email protected]  97. Retropharyngeal space It is interval between pharynx (Buccopharyngeal fascia) and prevertebral fascia Dr. Mavrych, MD, PhD, DSc [email protected]  above thyroid, it is only internal carotid, and below is common carotid 98. Carotid sheath Derived from all 3 layers. Encloses : 1. Common and internal carotid arteries, 2. Internal jugular vein 3. Vagus nerve some deep cervical lymph nodes, carotid sinus nerve, sympathetic nerve fibers (carotid periarterial plexuses) internal larygeal accompany superior larygenal artery Dr. Mavrych, MD, PhD, DSc [email protected] external larygeial nerve accompaniyes superior thyroid artery  99. Axillary sheath Derived from the prevertebral fascia Encloses the axillary vessels and brachial plexus as they emerge in the interval between the scalenus anterior and medius muscles – Interscalenus space Extends into the axilla Dr. Mavrych, MD, PhD, DSc [email protected]  100. Posterior Triangle of the Neck Summary: Scalene muscles Veins – external jugular vein, subclavian vein Arteries –occipital artery Nerves – accessory nerve (XI), trunks of the brachial plexus, branches of cervical plexus, phrenic nerve Lymph nodes – superficial cervical nodes along external jugular vein Dr. Mavrych, MD, PhD, DSc [email protected]  Good Luck! Dr. Mavrych, MD, PhD, DSc [email protected]