Anatomy Lecture Alternative Deck - Greater Emphasis on Post Midterm Material

Gross Anatomy

Study of structures visible to the naked eye

Sagittal Plane

Divides body into left and right halves

Midsagittal Plane

Divides body into equal left and right halves

Coronal Plane

Divides body into front and back halves

Transverse Plane

Divides body into top and bottom halves

Superior

Above

Inferior

Below

Anterior

Toward the front

Posterior

Toward the back

Lateral

Away from the midline

Medial

Toward the midline

Proximal

Closer to the trunk

Distal

Further from the trunk

Superficial

Toward or on the surface

Deep

Away from / beneath the surface

Flexion

Decreasing the angle at a joint

Extension

Increasing the angle at a joint

Axial Skeleton

Skull, ribcage (ribs + sternum), vertebral column

Appendicular Skeleton

Everything else — limbs and girdles

Long Bone

e.g., tibia, fibula

Short Bone

e.g., carpals (square-shaped)

Flat Bone

e.g., hip, skull, ribs — offer protection

Irregular Bone

e.g., vertebrae

Sesamoid Bone

Forms within tendons (e.g., patella)

Tendon

Connective tissue connecting muscle to bone

Ligament

Connective tissue connecting bone to bone

Fibrous Joint

Little to no movement (e.g., skull sutures)

Synovial Joint

Freely moving joint enclosed by articular capsule

Plane/Gliding Joint

Uniaxial; gliding (e.g., intercarpal joints)

Condyloid Joint

Biaxial; flexion, extension, abduction, adduction (e.g., MCP joint)

Saddle Joint

Biaxial + circumduction (e.g., 1st carpometacarpal)

Hinge Joint

Uniaxial; flexion and extension (e.g., elbow)

Pivot Joint

Uniaxial; rotation (e.g., proximal radioulnar)

Ball and Socket Joint

Multiaxial (e.g., shoulder, hip)

Intrinsic Ligament

Thickening of the joint capsule itself

Extrinsic Ligament

Supports a joint but located away from capsule

Concentric Contraction

Muscle shortens while producing force

Eccentric Contraction

Muscle lengthens while producing force

Isometric Contraction

Muscle length stays the same while producing force

Vertebral Column

33 vertebrae + intervertebral discs; allows flexion, extension, lateral flexion, rotation

Vertebral Regions

7 cervical, 12 thoracic, 5 lumbar, 5 sacral (fused = sacrum), 3–5 coccygeal (fused = coccyx)

Intervertebral Disc

Annulus fibrosus (outer ring) + nucleus pulposus (inner gel)

Atlanto-occipital Joint

C1 + occipital bone; head flexion/extension

Atlanto-axial Joint

C1 + dens of C2; head rotation

Primary/Kyphotic Curvature

Concave anteriorly; thoracic and sacral in adults

Secondary/Lordotic Curvature

Convex anteriorly; cervical and lumbar in adults

Kyphosis

Exaggerated thoracic curvature (hunchback)

Lordosis

Exaggerated lumbar curvature (swayback)

Scoliosis

Vertebral column deviates laterally

Erector Spinae

Deep back muscles (iliocostalis, longissimus, spinalis); maintain posture, control vertebral column movement

Pectoral Girdle

Scapula + clavicle

Glenohumeral Joint

Ball and socket; head of humerus in glenoid fossa; most mobile joint; stabilised by rotator cuff

Rotator Cuff (SITS)

Supraspinatus, Infraspinatus, Teres minor, Subscapularis

Supraspinatus — O/I/N/A

O: Supraspinous fossa; I: Greater tubercle; N: Suprascapular nerve; A: First 15° of shoulder abduction

Infraspinatus — O/I/N/A

O: Infraspinous fossa; I: Greater tubercle; N: Suprascapular nerve; A: External shoulder rotation

Teres Minor — O/I/N/A

O: Lateral border of scapula; I: Greater tubercle; N: Axillary nerve; A: External shoulder rotation

Subscapularis — O/I/N/A

O: Subscapular fossa; I: Lesser tubercle; N: Upper + lower subscapular nerves; A: Internal shoulder rotation

Deltoid — O/I/N/A

O: Lateral clavicle, acromion, spine of scapula; I: Deltoid tuberosity; N: Axillary nerve; A: Middle = abduction; anterior = flexion/internal rotation; posterior = extension/external rotation

Pectoralis Major — O/I/N/A

O: Sternum + medial clavicle; I: Lateral lip of bicipital groove; N: Medial + lateral pectoral nerves; A: Shoulder flexion, adduction, internal rotation

Pectoralis Minor — O/I/N/A

O: Ribs 3–5; I: Coracoid process; N: Medial pectoral nerve; A: Depresses/stabilises scapula

Serratus Anterior — O/I/N/A

O: Lateral ribs 1–8; I: Medial border of scapula; N: Long thoracic nerve; A: Protracts + upwardly rotates scapula

Trapezius — O/I/N/A

O: Base of skull, nuchal ligament, thoracic spinous processes; I: Lateral clavicle, acromion, spine of scapula; N: CN XI (Accessory nerve); A: Upper = elevate; middle = retract; lower = depress scapula

Latissimus Dorsi — O/I/N/A

O: Inferior 6 thoracic spinous processes, thoracolumbar fascia, iliac crest; I: Floor of bicipital groove; N: Thoracodorsal nerve; A: Shoulder extension, adduction, internal rotation

Rhomboid Major — O/I/N/A

O: T2–T5 spinous processes; I: Medial border of scapula; N: Dorsal scapular nerve; A: Retracts scapula, inferiorly rotates glenoid fossa

Rhomboid Minor — O/I/N/A

O: C7–T1 spinous processes; I: Medial border of scapula at root of spine; N: Dorsal scapular nerve; A: Retracts scapula, inferiorly rotates glenoid fossa

Levator Scapulae — O/I/N/A

O: Transverse processes of cervical vertebrae; I: Superior angle of scapula; N: Dorsal scapular nerve; A: Elevates scapula; inferiorly rotates glenoid fossa

Brachial Plexus

Roots C5–T1 → 3 trunks → 6 divisions → 3 cords → 5 terminal nerves

Musculocutaneous Nerve

Lateral cord; innervates biceps brachii, brachialis, coracobrachialis

Radial Nerve

Posterior cord; innervates all posterior arm + forearm muscles

Median Nerve

Lateral + medial cords; innervates most anterior forearm + lateral hand

Ulnar Nerve

Medial cord; innervates FCU, medial FDP + most intrinsic hand muscles

Axillary Nerve

Posterior cord; innervates deltoid + teres minor

Biceps Brachii — O/I/N/A

O: Long head = supraglenoid tubercle; Short head = coracoid process; I: Radial tuberosity + bicipital aponeurosis; N: Musculocutaneous nerve; A: Forearm supination, elbow flexion, shoulder flexion

Brachialis — O/I/N/A

O: Distal half anterior humerus; I: Coronoid process of ulna; N: Musculocutaneous nerve; A: Elbow flexion (strongest flexor)

Triceps Brachii — O/I/N/A

O: Long head = infraglenoid tubercle; Lateral head = posterior humerus proximal to groove; Medial head = posterior humerus distal to groove; I: Olecranon; N: Radial nerve; A: Elbow extension

Pronator Teres — O/I/N/A

O: Medial epicondyle + coronoid process; I: Midshaft radius; N: Median nerve; A: Forearm pronation, assists elbow flexion

Flexor Carpi Radialis — O/I/N/A

O: Medial epicondyle; I: Base of 2nd metacarpal; N: Median nerve; A: Wrist flexion + radial deviation

Palmaris Longus — O/I/N/A

O: Medial epicondyle; I: Palmar aponeurosis; N: Median nerve; A: Wrist flexion; vestigial (~15% lack it)

Flexor Carpi Ulnaris — O/I/N/A

O: Medial epicondyle, olecranon, posterior ulna shaft; I: Pisiform, hook of hamate, base of 5th metacarpal; N: Ulnar nerve; A: Wrist flexion + ulnar deviation

Flexor Digitorum Superficialis — O/I/N/A

O: Common flexor origin + shaft of radius; I: Middle phalanges of digits II–V; N: Median nerve; A: Flexes wrist + all finger joints except DIP

Flexor Digitorum Profundus — O/I/N/A

O: Interosseous membrane + ulna; I: Distal phalanges II–V; N: Lateral half = median nerve; medial half = ulnar nerve; A: Flexes all finger joints including DIP

Flexor Pollicis Longus — O/I/N/A

O: Interosseous membrane + radius; I: Distal phalanx of thumb; N: Median nerve; A: Flexes all thumb joints

Pronator Quadratus — O/I/N/A

O: Distal ulna; I: Distal radius; N: Median nerve; A: Forearm pronation

Brachioradialis — O/I/N/A

O: Lateral supraepicondylar ridge; I: Distal radius; N: Radial nerve; A: Elbow flexion in semi-prone position

Extensor Carpi Radialis Longus — O/I/N/A

O: Lateral supraepicondylar ridge; I: Base of 2nd metacarpal; N: Radial nerve; A: Wrist extension + radial deviation

Extensor Carpi Radialis Brevis — O/I/N/A

O: Common extensor origin; I: Base of 3rd metacarpal; N: Deep branch of radial nerve; A: Wrist extension + radial deviation

Extensor Digitorum — O/I/N/A

O: Common extensor origin; I: Distal phalanges II–V via extensor expansions; N: Deep branch of radial nerve; A: Wrist extension + extension of digits II–V

Extensor Carpi Ulnaris — O/I/N/A

O: Common extensor origin; I: Base of 5th metacarpal; N: Deep branch of radial nerve; A: Wrist extension + ulnar deviation

Supinator — O/I/N/A

O: Common extensor origin + supinator crest of ulna; I: Proximal third of radius; N: Deep branch of radial nerve; A: Forearm supination

Extensor Pollicis Longus (EPL) — O/I/N/A

O: Interosseous membrane; I: Distal phalanx of thumb; N: Deep branch of radial nerve; A: Extension of all thumb joints

Abductor Pollicis Longus (APL) — O/I/N/A

O: Interosseous membrane; I: Base of 1st metacarpal; N: Deep branch of radial nerve; A: Thumb abduction + extension

Carpal Tunnel

Space deep to flexor retinaculum; bounded by scaphoid tubercle, trapezium tubercle, pisiform, hook of hamate; contains FPL, FDS x4, FDP x4, median nerve

Carpal Tunnel Syndrome

Compression of median nerve → paresthesia/reduced sensation over lateral 3.5 digits + weakness of thenar muscles

Thenar Muscles

Abductor pollicis brevis, flexor pollicis brevis, opponens pollicis; all innervated by recurrent branch of median nerve

Adductor Pollicis

Innervated by deep branch of ulnar nerve; adducts thumb

Hypothenar Muscles

Abductor digiti minimi, flexor digiti minimi brevis, opponens digiti minimi; all innervated by ulnar nerve

Lumbricals (hand)

Origin: FDP tendons; Insertion: extensor expansions; 1st + 2nd = median nerve; 3rd + 4th = deep ulnar nerve; Action: flex MCP + extend IP joints

Dorsal Interossei (hand)

4 muscles; adjacent sides of all 5 metacarpals → extensor expansions; deep ulnar nerve; ABduct digits II–IV

Palmar Interossei (hand)

3 muscles; ADduct digits II, IV, V; deep ulnar nerve

External Oblique

Antero-inferior fibers; forms inguinal ligament (ASIS → pubic tubercle)