Anatomy Lab – Test 1
· Back
○ Objectives
§ The surface landmarks of the back.
§ The parts and details of the bony vertebral column, scapula, iliac crest and posterior skull as given on pages 4-6.
§ Muscles of the superficial, intermediate and deep back proximal and distal attachments, actions and innervations.
§ The greater occipital nerve (specifically) and recognize the segmental arrangement of the cutaneous branches of other dorsal primary rami.
§ The contents of the vertebral canal as detailed on pages 12-14.
○ Structures
§ Muscles:
· Superficial
○ Trapezius – has three parts and three distinct actions
○ Latissimus dorsi
○ Rhomboid major and minor – separation not very obvious, must be distinguished by distal attach
○ Levator scapulae
· Serratus posterior superior
· Serratus posterior inferior
· Splenius capitis and cervicis – deep to trap, go obliquely across the neck
○ Cervicis is on the outside
· Semispinalis capitis – one of the transversospinal muscles, can be identified at base of skull
○ Greater occipital nerve passes through here
○ Rotates to opposite side
· Erector spinae (3 parts)
○ Iliocostalis – most lateral
○ Longissimus
○ Spinalis – most medial
§ Nerves:
· Greater occipital nerve – is the dorsal ramus of spinal nerve C2
○ Pierces the trapezius right near the skull at the level of the ears
· Accessory nerve – can be seen deep to the trapezius
· Dorsal ramus
· Ventral ramus
· Spinal nerve
§ Arteries:
· Occipital artery – accompanies the greater occipital nerve
· Transverse cervical artery – accompanies the accessory nerve and the C3 & C4 branches
§ Other:
· Thoracolumbar fascia
· Triangle of auscultation
○ above, by the Trapezius
○ below, by the Latissimus dorsi
○ laterally by the medial margin of the scapula
· Lumbar triangle - medially by the latissimus dorsi muscle; laterally by the external abdominal oblique muscle; and inferiorly by the iliac crest
§ Spinal cord:
· Epidural space
· Dural sac, dura mater
· Arachnoid mater
· Subarachnoid space
· Denticulate ligaments
· Ventral and dorsal roots
· Dorsal root ganglion (spinal ganglion)
· Conus medullaris
· Cauda equina
· Filum terminale
§ Vertebrae:
· Atlas
· Axis
· Thoracic vertebra
· Lumbar vertebra
· Spinous and transverse processes
· Laminae and pedicles
· Articular processes – join to connect two vertebrae dorsal to the spinal cord
· Vertebral arch
· Vertebral foramina
· Intervertebral foramen
· Vertebral foramen
· Transverse foramen (cervical only) – where vertebral artery passes through
§ Scapula:
· Spine
· Acromion
· Lateral and medial borders – self explanatory
· Superior and inferior angles – topmost and bottommost points of scapula
· Shoulder
○ Objectives
§ Identify the bony landmarks of the shoulder.
§ Identify the muscles, nerves, vessels and ligaments indicated in the shoulder region (pgs 18-19).
○ Structures
§ Muscles:
· Scapulohumeral
○ Deltoid – axillary nerve and posterior circumflex humeral artery should be seen on the deep surface near attachment to humerus
○ Teres minor – also innervated by the axillary nerve (it is pretty close to the deltoid)
○ Teres major
○ Supraspinatus – suprascapular artery and suprascapular nerve found deep to here AND Infraspinatus by going around greater scapular notch
○ Infraspinatus
○ Subscapularis – not dissected here
· Triceps brachii
§ Nerves:
· Axillary
§ Other:
· Suprascapular ligament – army goes over the bridge, navy goes under
· Quadrangular space – teres minor, teres major, lateral and long head of tricep
○ Contains axillary and posterior circumflex humeral
· Triangular space – teres minor, teres major, lateral head of tricep
○ Contains circumflex scapular artery deep to it (not through)
§ Vessels:
· Thoracoacromial artery (and branches)
· Posterior humeral circumflex artery
· Deep brachial artery (profunda brachii) – found in trigular hilus
· Axilla
○ Objectives
§ Identify muscles, nerves and vessels indicated in the pectoral region (pgs. 43-46).
§ Identify the boundaries and contents of the axilla as indicated on pgs. 19-22.
§ Identify all of the branches of the axillary artery.
§ Identify all of the infraclavicular parts of the brachial plexus (cords, divisions and terminal branches).
○ Structures
§ Muscles
· Pectoralis major and minor
· Serratus anterior – upper 8 ribs in front, to medial border of scapula (so it wraps around)
· Latissimus dorsi
· Subclavius
· Teres major
· Subscapularis
§ Blood Vessels
· Cephalic vein – between deltoid and pec major in the deltopectoral triangle
· Pectoral branch of thoracromial artery – can travels with pectoral nerves in pecs?
· Axillary Artery – continuation of subclavian. Contains 3 parts
○ Note – branches are named by their distribution, not origin (due to variance)
○ Part 1 – superior thoracic artery
○ Part 2
§ Thoracromial artery – branch of axillary artery in 2nd part right behind pec minor
○ Clavicular branch – supplies subclavius muscle
○ Acromial branch
○ Deltoid branch – goes through deltopectoral groove
○ Pectoral Branch –
§ Lateral thoracic artery – under lateral border of pec minor, not always there, another branch of axillary artery
○ Part 3
§ Subscapular artery – largest branch and divides into circumflex scapular, thoracodorsal artery
○ Thoracodorsal artery travels with thoracodorsal nerve
§ Anterior and posterior circumflex arteries – posterior is larger
○ Posterior circumflex goes through quadrangular space, travels with axillary nerve
○ Both travel laterally
§ Nerves:
· The cords of the brachial plexus are named according to their relationship to the second part of the axillary artery
· Musculocutaneous nerve – use it to help find the lateral cord
○ Lateral cord also produces lateral root of the median nerve, which connects to the median nerve
· Median nerve can help you find median cord via the medial root of the median nerve
○ Medial cord → medial cutaneous nerve of the forearm and medial cutaneous nerve of the arm
· Posterior cord produces axillary, radial and the three subscapular (upper, middle, lower) nerves
○ The subscapular nerves run on the anterior surface of the subscapularis muscle and innervates the three muscles that form the posterior wall of the axilla
○ Axillary nerve passes posterior to the humerus and courses through the quadrangular space with the posterior circumflex humeral artery
· Medial pectoral – deep to the surface of each pec
○ Off of medial cord
· Lateral pectoral – deep to the surface of each pec
○ Off of lateral cord
· Radial
· Suprascapular
· Long thoracic nerve -
§ Other
· clavipectoral fascia – immediately deep to the pect major
· axillary sheath – CT that surrounds axillary vessels and brachial plexus
○ boundaries are the same as the axillary artery
· Arm and Flexor Forearm
○ Objectives
§ The structures listed in the cubital fossa, posterior and anterior fascial compartments of the arm as indicated on pgs. 22-30.
§ The bony landmarks of the arm.
§ The structures of the forearm highlighted on pgs. 26-29.
§ The bony landmarks of the forearm.
○ Structures
§ ARM
· Muscles:
○ Brachioradialis
○ Coracobracialis
○ Biceps brachii – tendon of long head of biceps brachii goes through intertubercular sulcus posterior to the transverse humeral ligament
○ Brachialis – deep to bicep brachii
○ Triceps – between the long head and the lateral head is an opening in which you can see the radial nerve and the deep artery of the arm
§ This is the triangular hilus/interval
· Nerves:
○ Axillary
○ Median – goes in intermuscular septum on medial side of arm
§ Goes through cubital fossa
§ Does not innervate muscles in the arm
○ Musculocutaneous – innervates all three muscles of anterior compartment
§ Enters coracobrachialis → goes between bicep and brachialis
§ Continues as Lateral cutaneous nerve of the forearm
○ Medial cutaneous nerve of the forearm – comes from brachial plexus, follows basilic vein?
○ Radial – deep to the triceps and lies directly on the posterior surface of the humerus in the radial groove
§ Innervates all muscles in the posterior compartment
○ Ulnar – goes over medial epichondyle
§ Does not innervate muscles in the arm
○ Upper, lower and middle subscapular
· Vessels:
○ Basilic vein
○ Brachial artery – continuation of axillary artery, begins at inferior border of teres major
§ In Arm – branches into deep artery of the arm, superior ulnar collateral artery, inferior ulnar collateral artery
§ At Elbow - Branches into radial artery and ulnar artery
○ Cephalic vein
○ Deep brachii artery – on lateral side of the arm (makes sense since it goes out with radial
○ Median cubital vein
· Other:
○ Bicipital aponeurosis and tendon
§ FLEXOR FOREARM
· Muscles:
○ Superficial flexors
§ Flexor carpi radialis
§ Flexor carpi ulnaris
§ Flexor digitorum superficialis – located deep to the other four muscles, has four tendons
○ Connects to middle phalanges
§ Palmaris longus
§ Pronator teres
○ Deep Flexors
§ Flexor digitorum profundus – connects to distal phalanges
§ Flexor pollicis longus
§ Pronator quadratus
· Nerves:
○ Ulnar – passes between the two heads of the flexor carpi ulnaris
○ Median – enters wrist in middle. Innervates most of the muscles in the flexor compartment
§ Is deep to the superficial group of flexor muscles
§ Anterior interosseous – passes deep to the pronator quadratus
○ Radial
§ Superficial
§ Deep
· Vessels:
○ Brachial artery – branches into radial and ulnar in the cubital fossa
○ Radial artery – follows radius
§ Can be seen at proximal forearm between brachioradialis and pronator teres
○ Ulnar artery
§ Common interosseous – branches
○ Anterior interosseous
○ Posterior interosseous
§ anterior ulnar recurrent artery and posterior ulnar recurrent artery – anastamose with collateral branches of brachial artery
· Other:
○ Interosseous membrane
§ Notes
· Path of median nerve in forearm was emphasized
· Path of radial nerve in arm was emphasized
· Extensor Forearm and Hand
○ Objectives
§ The bony landmarks of the hand.
§ The structures of the palm of the hand bolded and indicated on pgs. 30-35.
§ The structures of the extensor forearm and dorsum of the hand highlighted on pgs. 35-36.
○ Structures
§ EXTENSOR FOREARM and HAND
· Muscles:
○ Palmaris brevis – found superficial to the palmar aponeurosis What is This???
○ Thenar
§ Abductor pollicis brevis
§ Opponens pollicis – deep to abductor pollicis brevis
§ Flexor pollicis brevis
○ Hypothenar
§ Abductor digiti minimi
§ Opponens digiti minimi – again the deepest
§ Flexor digiti minimi
○ Deep
§ Lumbricals
§ Adductor pollicis
§ Palmar interossei – 3 of them. originate on only 1 metacarpal
§ Dorsal interossei – 4 of them. originate on 2 metacarpals
○ Snuff Box
§ Abductor pollicis longus
§ Extensor pollicis brevis
§ Extensor pollicis longus
○ Superficial Group
§ Extensor carpi radialis longus
§ Extensor carpi radialis brevis
§ Brachioradialis
§ Extensor carpi ulnaris
§ Extensor digitorum
○ Deep Group
§ Supinator – deep to brachioradialis
§ Extensor indicis
· Vessels:
○ Radial artery –
§ Deep palmar arterial arch
○ Ulnar artery
§ Superficial palmar arch
· Nerves:
○ Ulnar – divides after the pisiform bone
§ Deep branch – disappears into the hypothenar muscles
○ also innervates the interosseous muscles
§ Digital branch – forms the superficial palmar arch
○ Median
§ Recurrent branch – goes through carpal tunnel, innervates thenar muscles (and lumbrical muscles 1 and 2??)
○ Crosses surface of flexor pollicis brevis
§ Digital branches – also goes through the carpal tunnel???
○ Goes from 1 common branch for each finger, to 2 proper branches (on each side of finger)
○ Radial - goes through anatomical snuffbox. Can be found between brachioradialis and brachialis
§ Posterior interosseous – continuation of the deep branch of the radial nerve after it emerges from the supinator muscle
○ Provides motor branches for the extensor muscles of forearm
· Other:
○ Transverse carpal ligament (Flexor retinaculum)
○ Palmar aponeurosis – longitudinal fibers end by attaching to proximal phalanx
○ Fibrous digital sheaths – on flexor surface of each digit, contain flexor tendons
○ Extensor expansion – wrapped around the dorsum and the sides of the proximal phalanx and the distal end of the metacarpal bone. The hood-like expansion retains the extensor tendon in the midline of the digit. The tendons of the lumbrical and insterosseous muscles attach to the extensor expansion
§ Basically just tendon on fingers
· Thoracic Wall, Lungs and Pleura
○ Objectives
§ The bony landmarks and muscles of the thoracic wall.
§ The highlighted structures of the intercostal spaces and the isolated anterior thoracic wall (pgs. 46-48).
§ The extent and specific features of the pleural cavities.
§ 4. The structures of the right and left lungs as described on pages 50 and 51.
○ Structures
§ Thoracic wall/Lungs
· Note – each intercostal space is named after the rib above it
· Muscles:
○ Pectoralis major and minor
○ Serratus anterior
○ External intercostal – fibers oriented like hands in pocket
§ Elevates rib below
§ Becomes a membrane close to the sternum
○ Internal intercostal – fibers oriented the other way
§ Depresses rib above
§ Becomes membrane close to the vertebrae
○ Innermost intercostal – fibers oriented the other way
§ Stops before mid axillary line
○ Transversus thoracis – inside of thoracic wall, origin on sternum, insertion on above ribs
· Nerves:
○ Lateral cutaneous