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191 Cards in this Set

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Lymphatic drainage of the breast
Medial breast by parasternal nodes; deep breast by axillary nodes; lateral breast by pectoral nodes. Lymphatic obstruction by cancer causes thick leathery skin
Cooper ligaments
Attach the mammary gland to the skin. Distortion by breast cancer produces skin dimpling.
Irrigation of the breast
Internal thoracic, lateral thoracic and intercostal arteries.
Hematogenous route of breast metastasis to brain
Intercostal vein --> external vertebral plexus --> internal venous plexus --> cranial dural sinuses
Throracic outlet syndrome
Anomalous cervical rib compresses the lower trunk of brachial plexus, subclavian artery or both. Atrophy of thenar and hypothenar eminences, sensory deficit on medial side of forearm and hand
Boundaries of the mediastinum
Laterally by the pleural cavities, anteriorly by sternum, posteriorly by vertebral column.
Structures of the superior mediastinum
Thymus, superior vena cava, arch of the aorta, vagus, trachea, esophagus, thoracic duct
Branches of the arch of the aorta
Brachiocephalic trunk, left common carotid artery, left subclavian artery
Right and left recurrent laryngeal nerves
Right recurrent laryngeal nerve is in the neck and passes under the right subclavian artery to ascend to larynx. Left recurrent laryngeal nerve passes under aortic arch in the thorax to ascend to larynx. Both are branches of vagus nerves.
Landmarks of the trachea
From below the cricoid cartilage (C6) to the carina (behind sternal angle)
Landmarks of the esophagus
Cricoid cartilage (C6) to esophageal hiatus of the diaphragm (T10). It lies posterior to the trachea.
Structures of the middle mediastinum
Pericardium, phrenic nerves, heart
Phrenic nerves
Arise from ventral rami of C3, C4, C5. Motor inervation of the diaphragm and sensory innervation of the diaphragmatic pleura. Pass through the middle mediastinum lateral to the pericardium. Injury results in pleuritic chest pain irradiated to shoulder and neck
Structures of the anterior mediastinum
Thymus, fat and areolar tissue
Structures of the posterior mediastinum
Descending aorta, esophagus, thoracic duct, azygous vein, splachnic nerves, vagus nerves and sympathetic trunk.
Borders of the heart
Right border is right atrium; left border is left atrium and ventricle; inferior border is right ventricle.
Surfaces of the heart
Posterior surface (base) is left atrium; anterior surface is right ventricle; diaphragmatic surface (inferior) left ventricle
What nerve roots form the superior trunk of brachial plexus?
C5, C6
What nerve roots form the middle trunk of the brachial plexus?
C7
What nerve roots form the inferior trunk of the brachial plexus?
C8, T1
Muscles innervated by the axillary nerve
Deltoid and teres minor
Muscles innervated by the musculocutaneous nerve
Biceps, brachial, choracobrachial
Muscles innervated by the radial nerve
Triceps and extensor muscles on the posterior compartments of arm and forearm
Muscles innervated by the ulnar nerve
Flexor carpi ulnaris, medial part of the flexor digitorus profundus, lumbricals 3 and 4, palmar interosseous, dorsal interosseous, adductor pollicis, abductor digiti minimi, flexor digiti minimi, opponens digiti minimi
Muscles innervated by the median nerve
Flexor muscles of the forearm except flexor carpi ulnaris and medial part of flexor digitorus profundus, lumbricals 1 and 2, abductor pollicis brevis, opponens pollicis brevis, flexor pollicis brevis.
Actions of the axillary nerve
Abduct shoulder (deltoid), lateral roation of the shoulder (teres minor)
Actions of the musculocutaneous nerve
Flexes elbow (biceps, chorachobrachial), supination (biceps brachii)
Actions of the radial nerve
Extends digits, wrist and elbow. Supination.
Actions of the ulnar nerve
Flexes wrist and digits 4 and 5. Abducts and adducts digits 2, 3, 4, 5.
Actions of the median nerve
Flexes wrist and digits, pronation; abduction, opposition and flexion of the thumb
Clinical features of injury of the upper trunk of the brachial plexus
C5, C6 are injured due to adduction traction of the arm and hyperextension of the neck (fall on shoulder or pull baby by the neck). Results in Erb-Duchene paralysis damaging axillary, musculocutaneous, suprascapular and phrenic nerves. Loss of shoulder and anterior arm muscles. Arm is medially rotated and adducted, forearm is extended and pronated (waiter's tip)
Clinical features of injury of the lower trunk of the brachial plexus
C8, T1 are injured by a sudden abduction upward pull of the arm (pull baby by the arm). Results in thoracic outlet syndrome damaging median and ulnar nerves as well as T1 sympathetics. Loss of muscles of forearm and hand and Horner's syndrome (ptosis, miosis, anhydrosis)
Long thoracic nerve injury
Paralysis of the serratus anterior. No abduction of the arm past the horizontal position. Can't push (winging of the scapula)
Axillary nerve injury
Injured by fracture at the surgical neck of humerus or anterior dislocation of the shoulder. Cant abduct the shoulder to the horizontal plane, cant lateral rotate shoulder (teres minor). Sensory loss at the shoulder.
Radial nerve injury at the axilla
Shoulder dislocation or pressure on the floor of the axilla. No extension of the elbow, wrist or digits. Weak supination. Sensory loss of posterior arm, posterior forearm and posterolateral hand. "Wrist drop"
Radial nerve injury at the arm
Midshaft fracture of the humerus. No extension of the wrist or digits. Sensory loss on the posterior forearm and posterolateral hand. "Wrist drop"
Radial nerve injury at the wrist
Sensory loss on the lateral part of the dorsum of the hand. No extension of the digits.
Median nerve injury at the elbow
Supracondylar fracture of the humerus. Weak flexion of the wrist with ulnar deviation upon flexion. No flexion of digits 1 and 2, thenar muscles and lumbricals 1 and 2. Sensory loss on lateral palm and fingers 1, 2 and 3. Flattening of the thenar eminence (ape hand) and index and middle fingers cant make a fist.
Median nerve injury at the wrist
Slashing of the wrist (suicide attempt). Loss of thenar muscles and lumbricals 1 and 2. Sensory loss on lateral palm and fingers 1, 2 and 3. Flattening of the thenar eminence (ape hand) and index and middle fingers cant make a fist.
Ulnar nerve injury at the elbow
Fracture of the medial epicondyle of the humerus. Hand deviates radially when flexed (injured flexor carpis ulnaris), no flexion of ring and little fingers (injured flexor digitorus profundus and lumbricals 3, 4), abduction and adduction of the fingers is lost (injured palmar and dorsal interosseous), no adduction of the thumb, no movement of little finger. Sensory loss on lateral half of ring finger and little finger. "Claw hand".
Ulnar nerve injury at the wrist
Slashing of the wrist (suicide attempt). Loss of abduction and adduction of the digits, loss of hypothenar muscles and lumbricals 3, 4. Sensory loss on lateral half of digit 4 and 5. "Claw hand".
Musculocutaneous nerve injury
Loss of elbow flexion and weak suppination. Loss of sensation on lateral aspect of the forearm.
Branches of the brachiocephalic trunk
Right subclavian and right common carotid arteries
Branches of the subclavian artery
Internal thoracic artery (continuous with superior epigastric and inferior epigastric which provide colateral circulation in postductal coarctation of the aorta), vertebral artery.
Branches of the axillary artery
Thoracoacromial, lateral thoracic (mammary gland), subscapular (collateral to shoulder), posterior and anterior humeral circumflex arteries.
Branches of the brachial artery
Deep brachial artery (together with radial nerve at midshaft of humerus), ulnar artery and radial artery at the cubital fossa.
Branches of the ulnar artery
Common interosseous artery and superficial palmar arch
Branches of the radial artery
Deep palmar arch
Rotator cuff muscles
Subscapularis, Infraspinatous, Teres minor, Supraspinatous. "SITS"
What are the joints of the elbow and what is the function of each?
Humeroulnar and humeroradial permit flexion and extension. The radioulnar permits pronation and supination.
Wrist and hand joints
Radiocarpal joint (between the distal radius and scaphoid/lunate carpal bones), ulnocarpal joint, midcarpal joint (between proximal and distal carpal bones), carpometacarpal joints.
What are the carpal bones
From lateral to medial. Proximal row: scaphoid, lunate, triquetrum, pisiform. Distal row: trapezium, trapezoid, capitate, hamate.
What are the structures in the carpal tunnel?
Flexor digitorum superficialis (4 tendons), flexor digitalis profundus (4 tendons), flexor pollicis longus and median nerve.
Fracture of the scaphoid bone
Results in avascular necrosis of the proximal head of the scaphoid.
Lunate bone dislocation
Results in median nerve compression in the carpal tunnel
How many cervical vertebrae are there?
Seven
Main characteristic of cervical vertebrae
They have an opening in the transverse process - the transverse foramina - which carries vertebral artery and vein.
What artery does the vertebral artery emerge from?
Subclavian artery
Why are transient ischemic attacks produced?
Compression of the vertebral artery within the transverse foramina of the cervical vertebrae by osteoarthritic osteophytes
How many throracic vertebrae are there?
Twelve
What vertebrae does the 3rd rib articulate with?
Superior portion of T3 and inferior portion of T2
Where does the C4 spinal nerve exit from the spine?
The intervertebral foramen formed by C4 and C3
Where does the C8 spinal nerve exit from?
The intervertebral foramen formed by T1 and C7
Where does the T3 spinal nerve exit from?
The intervertebral foramen formed by T2 and T3
Where does the L5 spinal nerve exit from?
The intervertebral foramen formed by L4 and L5
What nerve root does herniation of L5/S1 disc affect?
S1
What nerve root does herniation of T12/L1 disc affect?
L1
Structure of the intervertebral disc
Center part is semigelatinous nucleus pulposus surrounded by fibrocartilage anulus fibrosus
What nerve root does herniation of C5/C6 disc affect?
C6
Boundaries of the intervertebral foramen
Superiorly and inferiorly by the pedicles; anteriorly by the bodies; posteriorly by the zygapophyseal joint.
What is kyphosis?
Exageration of the thoracic curvature in the elderly
What is lordosis?
Exageration of the lumbar curvature in pregnancy, spondylolisthesis or beerbelly
Defect in spina bifida oculta
Vertebral arch is absent.
What is scoliosis?
Lateral deviation or torsion caused by polio, leg length discrepancy, hip disease or hemivertebrae
Spondylolysis
Chronic stress fracture of pars interarticularis (between pedicle and lamina). Associated with young athletes (L5). Scottie Dog x-ray
Spondylolisthesis
Pedicles degenerate or don’t develop. Affected vertebra moves anteriorly with respect to the one below it. Ususally L4/L5 (degenerative) or L5/S1 (congenital)
Spondylosis
Degenerative process in elderly with formation of osteophytes and bone spurs.
Ankylosing spondylosis
Inflammatory osteoarthritis, ossification of anulus fibrosus results in lack of mobility and "bamboo" spine. HLA-B27
Route of metastasis to brain
From breast, lung or prostate via internal vertebral venous plexus, basivertebral veins or external vertebral venous plexus.
What structures can compress a spinal nerve root?
The intervertebral disc herniates posterolaterally or the zygapophyseal joint.
How is a spinal nerve formed?
The dorsal sensitive root and the ventral motor root; the dorsal root cell bodies are in the dorsal root ganglion; the ventral root cell bodies are in the gray matter of the spinal cord
What are the meninges?
From inside out: pia mater (attached to spinal cord), arachnoid and dura mater. Outside of the dura is the epidural space; between pia and arachnoid is the subarachnoid space and contains CSF.
What is the inferior limit of the spinal cord?
L1/L2
Where is the spinal tap performed?
L4/L5 disc
What are the layers that the neddle must pass to perform the spinal tap?
Skin, superficial fascia, deep fascia, supraspinous ligament, interspinous ligament, interlaminar space, epidural space, dura, arachnoid, subarachnoid space.
Sympathetic innervation of head and neck viscera
T1 and T2 via superior cervical ganglion
Sympathetic innervation of the heart
T1 via cervicothoracic ganglion and T3
Sympathetic innervation of the trachea, bronchi and lungs
T1 via cervicothoracic ganglion and T3
Sympathetic innervation of foregut and midgut
T4, T5, T6
Sympathetic innervation of cutaneous organs
T7-T12
Sympathetic innervation of smooth muscle and glands of hindgut and pelvic viscera
L1, L2
Parasympathetic innervation of pupillary sphincter
III cranial nerve via ciliary ganglion
Parasympathetic innervation of cilliary muscle
III cranial nerve via ciliary ganglion
Parasympathetic innervation of the submandibular and sublingual gland
VII cranial nerve via submandibullar ganglion
Parasympathetic innervation of lacrimal gland, nasal and oral mucosa
VII cranial nerve via pterygopalatine ganglion
Parasympathetic innervation of parotid gland
IX cranial nerve via otic ganglion
Parasympathetic innervation of thoracic and abdominal viscera
X cranial nerve
Parasympathetic innervation of hindgut and pelvic viscera
S2-S4
Lymphatic drainage of the breast
Medial breast via parasternal nodes; deep breast via axillary nodes; lateral breast via pectoral nodes
What are the cooper ligaments and clinical significance
Attach the mammary gland to the skin. A tumor mass distorts these ligaments and causes dimpling of the skin
Structure and articulations of the sternum
Manubrium articulates with clavicle and first rib; sternal angle is formed by union of manubrium and body of sternum and it articulates with the 2nd rib; body of the sternum articulates with ribs 3-7
Disk herniation: C4/C5
Compression of C5. Affects axillary nerve, shoulder and lateral surface of upper limb, deltoid muscle. Weak abduction of the arm.
Disk herniation: C5/C6
Compression of C6. Affects musculocutaneous nerve, thumb, biceps brachialis, brachio-radialis. Weak flexion of forearm, supination or pronation.
Disk herniation: C6/C7
Compression of C7. Affects radial nerve, posterior surface of upper limb, middle and index fingers, triceps and wrist extensors. Weak extension of forearm and wrist.
Disk herniation: L3/L4
Compression of L4. Affects femoral nerve, medial surface of the leg, big toe, quadriceps. Weak extension of the knee.
Disk herniation: L4/L5
Compression of L5. Affects common peroneal nerve, lateral surface of the leg, dorsum of the foot, tibialis anterior, extensor hallucis lingus, extensor digitorum longus. Weak dorsiflexion of ankle and extension of toes.
Disk herniation: L5/S1
Compression of S1. Affects tibial nerve, posterior surface of lower limb, little toe, gastrocnemius and soleous. Weak plantar flexion and flexion of toes.
Teardrop fracture
Hyperflexion of the cervical region (car accident, diving into shallow water). Teardrop fracure of anterior vertebral body, posterior subluxation of the vertebra, fracture of spinous process, tear of anterior and/or posterior longitudinal ligaments. Quadriplegia and loss of sensation.
Jefferson fracture
Caused by compression of cervical region. Multiple fracture of C1, lateral displacement of C1, tear of transverse ligament.
Hangman fracture
Caused by hyperextension of cervical region (hanging, car accident in which chin hits dashboard). Bilateral fracture of pars articularis of C2, anterior subluxation of C2, tear of anterior longitudinal ligament.
Chance fracture
Caused by hyperflexion of lumbar column (car accident with lap seat belt only). Transverse fracture of vertebral body and spinous process, rupture of intervertebral disk and tear of posterior longitudinal ligament.
Muscles of the abdominal wall
External oblique, internal oblique, transverse, rectus abdominus, transversalis fascia
What structures form the roof of the inguinal canal?
Internal abdominal oblique and transverse abdominus muscles
What structures form the anterior wall of the inguinal canal?
Aponeurosis of the external and internal abodminal oblique muscles
What structures form the floor of the inguinal canal?
Inguinal ligament
What structures form the posterior wall of the inguinal canal?
Transversalis fascia (laterally) and cojoined tendon (medial)
What are the contents of the spermatic cord and where do they derive from?
External spermatic fascia (derives from external oblique fascia), middle spermatic fascia and cremaster muscle (internal oblique muscle), internal spermatic fascia (transversalis fascia), testicular artery, Pampiniform venous plexus, vas deferens
Where and what forms the deep inguinal ring?
Its formed by the transversalis fascia just lateral to the inferior epigastric vessels
Direct inguinal hernia
Protrussion through the posterior wall of inguinal canal (triangle of Hasselbach) medial to the inferior epigastric vessels and deep inguinal ring
Indirect inguinal herna
Protrussion through the deep ingiunal ring and courses through the inguinal canal
What is the cause of a congenial indirect inguinal hernia?
Persistence of the process vaginalis
MCC site of femoral hernia
Medial from femoral vein just below inguinal canal. MC in women.
Bones of the posterior abdominal wall
Ileum (iliac crest, iliac fossa), five lumbar vertebra, 12th rib, lesser trocanter of femur
Muscles of the posterior abdominal wall
Psoas, quadratus lumborum, iliacus
Muscle that flexes the hip
Psoas major
Lobes of the liver
Right and left lobes divided by the falciform ligament. Right lobe is subdivided into quadrate, proper and caudate lobes
Omental bursa
Cavity behind the stomach, has epiploic foramen
Structures of the epiploic foramen
Anteriorly the portal triad and hepatoduodenal ligament. Posteriorly the inferior vena cava and head of the pancreas
Structures and associations of the portal triad
Portal vein, hepatic artery and common bile duct. Associated with the hepatoduodenal ligament and the free border of the lesser omentum
How is the common bile duct formed?
By the cystic (gallbladder) duct and the common hepatic duct
What are the pancreatic ducts and where do they open?
Major duct of Wirsung (developes from ventral pancreatic diverticulum) and minor duct of Santorini (develop from dorsal pancreatic diverticulum). They open into the 2nd portion of the duodenum.
Irrigation of the pancreas
The head is irrigated by superior and inferior pancreaticoduodenal arteries. The body and tail from the splenic arteries.
Major branches of the abdominal aorta
Celiac trunk, superior mesenteric, inferior mesenteric, right and left renal arteries. It bifurcates into the common iliac arteries which further divide into the internal and external iliac arteries.
Branches of the celiac trunk
Left gastric artery (lesser curvature of stomach), splenic artery, common hepatic artery
Branches of the common hepatic artery
Proper hepatic artery and gastroduodenal arteries. Gastroduodenal artery branches into gastroepiploic artery (major curvature of stomach) and pancreaticoduodenal artery.
Irrigation of the colon
Cecum, ascending colon and proximal 2/3 of the transverse colon irrigated by superior mesenteric artery. Distal 1/3 of the transverse colon, descending colon, sigmoid and rectum irrigated by inferior mesenteric artery
Branches of the superior mesenteric artery
Ileocolic, right colic and middle colic arteries.
Branches of the inferior mesenteric artery
Left colic, sigmoid and superior rectal arteries
Gallstone ileus
Large stone passes through a fistula between gallbladder and small bowel which allows air to enter biliary tree and obstructs ileocecal valve
Prepatellar bursitis
Due to prolonged kneeling. Knee pain, erythema, swelling
Acromioclavicular ligament
Between acromion and clavicle in the distal end
Coracoclavicular ligament
At the proximal clavicle
Median nerve trajectory at the wrist
Between flexor digitorum superficialis and profundus then carpal tunel
Supraspinatous tendon
Between acromion and the head of the humerus; most affected by rotator cuff injury
Loud noises
Deafness due to injury of hair cells of the organ of corti; high frequency sounds first
Posterior duodenal ulcer affects which structure?
Gastroduodenal artery; results in hemorrhage
Catheter access to aorta from femoral vein
Has to puncture fossa ovalis and pass mitral valve
Superior mesenteric artery relationships
Forms a 45 degree angle with aorta which overrides horizontal portion of the duodenum (posterior to SMA)
Bones that articulate with the radius at the wrist
Scaphoid (lateral) and lunate (medial)
Ulnar nerve injury
Results in claw hand; injury usually at the medial epicondyle or hook of the hamate and pisiform in the wrist
Site for intramuscular injections
Superolateral quadrant of the buttocks
Sternocleidomastoid muscle
Originates in medial clavicle and manubrium and inserts in the mastoid process; rotates head to opposite side innervation by the XI nerve
Winged scapula
Injury of long thoracic nerve which supplies serratus anterior and abducts the shoulder to horizontal position; can be caused by trauma or mastectomy
Associations of the duodenum
First portion is not retroperitoneal; second portion with the head of the pancreas and ampulla of Vater; third (horizontal) portion with the superior mesenteric artery (anteriorly) and aorta (posteriorly)
Middle meningeal artery
Branch of maxillary artery; fracture of the pterion results in damage and epidural hematoma
Pterion
Fronto-parieto-temporal junction at the sphenoid bone; fracture results in middle meningeal artery damage
Recurrent laryngeal nerve
Motor innervation of all laryngeal muscles except cricothyroid; sensory innvervation below vocal cords
Superior laryngeal nerve
Motor innervation of cricothyroid muscle and sensory innervation above vocal cords
Tibial nerve
Motor innervation of flexors of the leg and toes and sensory innervation of sole of the foot
Retroperitoneal hematoma
Trauma to tail of the pancreas
Knee joint structures
Anterior and posterior cruciate ligaments; lateral and medial meniscus; medial (tibial) and lateral (fibular) collateral ligaments; injured in contact sports
Trendelenburg sign
Hip moves downward when ipsilateral leg is lifted off ground --> injury to superior gluteal nerve
Superior orbital fissure
CN III and CN V1 passage; injury results in external strabismus and loss of corneal reflex
Sound perception
Low frequency sounds --> apex of the cochlea/helicotrema; high frequency sounds --> base of cochlea
Avascular necrosis of the femoral neck
Damage to medial femoral circumflex artery
Midshaft fracture of the humerus
Damages radial nerve and deep brachial artery
Supracondylar fracture of the humerus
Damage to brachial artery and median nerve
Popliteal fossa structures
Popliteal artery, vein and tibial nerve (flexion of the foot)
Trauma to the head of the fibula
Damage to common peroneal nerve which divides into superficial (lateral compartment of the leg) and deep (anterior compartment and dorsiflexion of foot) peroneal nerves; results in foot drop injury
Divisions of sciatic nerve
Common peroneal and tibial nerves; just proximal to the popliteal fossa
Diaphragmatic surface of the heart
inferior wall of the left ventricle
Pudendal block
Intravaginally near the tip of the ischial spine
Origin of musculocutaneous nerve
Ventral rami of C5-C7 trunk
Abduction of the thigh
Superior gluteal and femoral nerves
Adduction of the thigh
Obturator nerve
Flexion of the thigh
Psoas and iliacus muscles innervated by lumbar plexus and femoral nerves
Irrigation of lesser curvature
left gastric artery
Relationships of the ureters
Cross over external iliac and pass lateral to the internal iliac and medial to gonadal arteries
Suspensory ligaments of the ovary
Deliver nerves and vessels to the ovary
Thoracocentesis
Lower border of parietal pleura is 7th rib/MCL or upper border of 10th rib/MAL; lower border of lung is 2 intercostal spaces above pleural border; therfore insert needle at 7th rib/MCL or 9th rib/MAL
Important nuclei of the thalamus
spinothalamic/medial lemniscus --> VPL; trigeminal --> VPM; auditory --> MGB; visual --> LGB
Sensory innervation of the tongue
General sensation of anterior 2/3 --> trigeminal; gustatory sensation anterior 2/3 --> facial (chorda tympani); posterior 2/3 --> CN IX
Phrenic nerve
C3-C5 --> motor innervation of diaphragm and sensory innervation of diaphragmatic pleura; irritation results in pleuritic chest pain irradiated to shoulder and neck
Branches of radial nerve
Deep (motor), superficial (sensory); branch at lateral epicondyle of humerus where it meets radial head --> injury results in motor deficit without sensory loss
Stapedius muscle
Innervated by branch of CN VII --> paralysis --> hyperacusis
Superior limits of the lungs
Above the clavicle; puncture wound to neck can cause pneumothorax
Drainning of testicles
Right to IVC; left to left renal vein
Horseshoe kidney
Ascension is prevented by angle between aorta and inferior mesenteric artery
Hydrocele
Fluid acumulation within tunica vaginalis
Thoracic duct
Enters thorax through aortic hiatus; empties into left subclavian
Inferior vena cava
Formed by union of common iliac veins at L4; renal veins join IVC at L1/L2