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WHERE AM I?. Online Anatomy Module 1. INTRO & TERMS. CELL. EPITHELIUM. CONNECTIVE TISSUE. MUSCLE. NERVOUS SYSTEM. AXIAL SKELETON. APPENDICULAR SKELETON. MUSCLES. EMBRYOLOGY. SKELETON: Divisions. SKULL. VERTEBRAL COLUMN. PECTORAL GIRDLE. RIBS. LIMB BONES. PELVIC GIRDLE.
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WHERE AM I? Online Anatomy Module 1 INTRO & TERMS CELL EPITHELIUM CONNECTIVE TISSUE MUSCLE NERVOUS SYSTEM AXIAL SKELETON APPENDICULAR SKELETON MUSCLES EMBRYOLOGY
SKELETON: Divisions SKULL VERTEBRAL COLUMN PECTORAL GIRDLE RIBS LIMB BONES PELVIC GIRDLE LIMB BONES Marieb Fig 5.6, p 121
2 SKELETONS APPENDICULAR SKELETON PECTORAL GIRDLE CLAVICLE (Collar bone) omitted LIMB BONES upper PELVIC GIRDLE LIMB BONES lower appendicular skeleton hangs on the axial
PECTORAL GIRDLE The pectoral girdle is not a 19th-century corset for the upper chest On each side, it is a pair of bones that allows the arm to be fastened to the body, but to have an amazing range of movements & uses The arm is used for: swinging, crawling, reaching, pulling, throwing, twisting; & for positioning, orienting, stabilizing & controlling all that the hand does The bones of the pectoral girdle are the shoulder-blades & the collar-bones
PECTORAL GIRDLE The bones of the pectoral girdle are the shoulder-blades & the collar bones SCAPULA or SHOULDER-BLADE CLAVICLE or COLLAR-BONE
SCAPULA The SCAPULA is a peculiarly-shaped bone, with many surfaces, edges and protuberances for muscles (& ligaments) to attach. These are needed to control the arm directly, but also to position and stabilize the scapula for whatever the arm is doing The scapula is a highly mobile bone The arm is used for: swinging, crawling, reaching, pulling, throwing, twisting, etc; & for positioning, orienting, stabilizing & controlling all that the hand does
SCAPULA Shoulder-blade PECTORAL GIRDLE The scapula is the major part of the pectoral girdle & lies posteriorly The scapula is a shallow dish, with the concave side facing anteriorly, as it fits over the muscles & ribs of the back
SCAPULA: Terminology Acromion process Coracoid process Spine Vertebral margin Glenoid fossa Inferior angle Needless to say, each side and angle has a name. Here are enough to be going on with.
Spine SCAPULA: Parts I The SPINE rises and thickens from the medial edge going laterally, forming a triangular ridge ending in a protuberance termed the ACROMION The spine defines territories above & below it, into which muscles fit Acromion = Acromion process
SCAPULA: Parts II ACROMION PROCESS improves the angle of action of the deltoid muscle pulling the arm away from the body, & anchors the lateral end of the clavicle Medial/Vertebral margin Spine Coracoid process Lies by the spines of vertebrae from which muscles attach to it Glenoid fossa
CORACOID PROCESS Acromion process Anterior beak to improve angle of biceps muscle GLENOID FOSSA Spine humerus Shallow socket for head of the humerus SCAPULA: Parts III Medial/Vertebral margin
SCAPULA: Parts IV Viewed from side Acromion process Coracoid process Anterior beak to improve angle of pull of biceps muscle humerus Spine Glenoid fossa
SCAPULA & CLAVICLE The SCAPULA is a peculiarly-shaped bone, with many surfaces, edges and protuberances for muscles (& ligaments) to attach. These are need to control the arm, but also to position and stabilize the scapula for whatever the arm is doing The scapula is a highly mobile bone The arm is used for: swinging, reaching, pulling, throwing, twisting; & for positioning, orienting, stabilizing & controlling all that the hand does The CLAVICLE is the strut that: holds the shoulder out away from the trunk;absorbs shock;fastens appendicular to axial skeleton ; & anchors several muscles & ligaments (at the sterno-clavicular joint)
CLAVICLE The arm is used for: swinging, crawling, reaching, pulling, throwing, twisting; & for positioning, orienting, stabilizing & controlling all that the hand does The CLAVICLE is the strut/brace that: holds the shoulder out, away from the trunk; absorbs shock; & fastens appendicular to axial skeleton (at the sterno-clavicular joint) & anchors several muscles & ligaments
Connections between axial & appendicular skeletons I Sterno-clavicular joint CLAVICLE Sterno-clavicular joint STERNUM SCAPULA rotated unnaturally Sternum
Connections between axial & appendicular skeletons I Sterno-clavicular joint Acromio-clavicular joint CLAVICLE Scapula has no other joints, Hence NO joint with axial skeleton. Jugular notch STERNUM SCAPULA rotated unnaturally Manubrium Sternum body Sterno-clavicular joint Marieb Fig 5.20, p 133
CLAVICLE Left versus Right I The clavicle has a lumpy sternal end & a blade-like acromial end The upper surface is smoother* than the inferior one, because ligaments etc come from below to attach to tuberosities The clavicle is a pulled-out S-shape Use these three features to ID left from right thus: “Smooth” - feel on yourself
1 2 3 CLAVICLE Left versus Right II Place the clavicle on your chest with the lumpy end at your breast-bone Try on right & left sides to make the first curvature going outward from the breast-bone face forward Front Back If the upper surface is not the smoother one, move the clavicle (keeping orientations 1 & 2) to the other side It should now be identifiable as Rt or Lft
Connections between axial & appendicular skeletons II Sacro-iliac joint SACRUM of axial is wedged into the hip bones of the appendicular pelvic girdle For stability & the transmission of load via the hip bones to the legs Sacro-iliac joint Marieb Fig 5.18, p 132
COMMON BONE TERMS PROCESS Protuberance Tuberosity small bump FOSSA Spine Spine Shallow depression Margin Border Edge Head Angle
COMMON BONE TERMS PROCESS has become an overused word In anatomy, as noun, it means something that sticks out or protrudes from a cell, from a bone, or from a soft organ In anatomy, as noun, process still also means the way in which something occurs - the process of cell division, the process of shrinking, of winking To give slow-witted politicians more time to think, the last example has been horribly extended by their speech-writers - for example, ‘deciding’ is a noun and does not need to be the ‘decision-making process’. Thus, “deciding that won’t be easy” , “wine-making is fun” are natural & correct English
HUMERUS Viewed from behind Is the single bone of the ARM Proximally, it articulates with the scapula at the shoulder Distally, it articulates with two bones of the forearm at elbow joint It has specially shaped surfaces at the elbow to allow the ulna & radius their movements At the elbow, it has depressions engaging processes of the ulna to limit its movement It has several tuberosities and much surface , including epicondyles, for the attachment of muscles
HUMERUS I Viewed from front HEAD Deltoid tuberosity Coronoid Fossa Lateral Epicondyle Medial Epicondyle Capitulum Trochlea
HUMERUS II Viewed from behind Olecranon Fossa HEAD Deltoid tuberosity Medial Epicondyle Lateral Epicondyle Trochlea
HUMERUS Right versus Left 1 On yourself, place the rounded head of the humerus at either shoulder 2 Turn the head so that it faces medially (inward) at that shoulder At the elbow end, look for the shallow coronoid fossa on one side & the deeper olecranon fossa on the other 3 Keeping orientations 1 & 2, move the humerus to the side that has the deep olecranon fossa facing posteriorly As one extends the elbow, the olecranon process of the ulna locks into the fossa on the humerus, preventing hyperextension
DISTAL HUMERUS Viewed from front Trochlear is a noun, not an adjective The Trochlear is a spool-like rolling surface for the ulna The Capitulum is a little sphere-like structure: a surface for rotation The Capitulum matches a dimple in the symmetrical head of the radius bone For the name, remember that capital punishment used often to include beheading
RADIUS I Viewed from in front Head Neck Radial tuberosity Styloid process Articular surface for wrist/carpal bones
RADIUS II Viewed from in front Head Neck Radial tuberosity Sharp edge - Interosseous border/margin Concave surface - space for muscles Feel for yourself: the back of the forearm is bony, the front, squishy Styloid process Articular surface for wrist/carpal bones
RADIUS: Right versus Left Radius lies laterally to ulna Head lies at elbow end Sharp edge faces medially towards ulna Concave surface - space for muscles - faces forward Styloid process sort-of points laterally
RADIUS & ULNA: Cautions Head The head of the ulna is at the wrist end The ulna also has a styloid process. The two help hold the carpal bones in place. Styloid process
ULNA I Olecranon Viewed from in front Palpable at the back of the elbow, when you flex & extend it Radial notch Caution - on the ulna ! Coronoid process Ulnar head Styloid process
ULNA II Olecranon Viewed from in front Palpable at the back of the elbow, when you flex & extend it Radial notch Caution - on the ulna ! Coronoid process Head of ulna Ulnar head The bump lying laterally on the back of your wrist, when it is pronated (palm down) Styloid process
ULNA III Olecranon Coronoid process Radial notch allows the radius to rotate against the ulna for supination-pronation movements Concave surface - space for muscles Interosseous margin for strong fibrous attachment to the radius Styloid process Head
ULNA IV Olecranon Viewed from lateral side Radial notch Coronoid process allows the radius to rotate against the ulna for supination-pronation movements a ligament holds the radius in place The elbow end of the ulna is distinctive, with its hook-like olecranon process for raking in the chips at the neolithic gaming table
HUMERUS Viewed from behind It has specially shaped surfaces at the elbow to allow the ulna & radius their movements At the elbow, it has depressions engaging processes of the ulna to limit its movement - behind, the Olecranon fossa takes olecranon of ulna to limit extension of the elbow rotated unnaturally
Back to the forearm Right FOREARM BONES RADIUS ULNA RADIUS on thumb side ULNA on little-finger side A relation kept during pronation
ANTERIOR Right FOREARM: Radius & Ulna RADIUS PRONATED SUPINATED Radius rotates on two radio-ulnar joints Two bones are held together by ligaments & the interosseous membrane Thumb medial Thumb lateral
ULNA: Right versus Left Ulna lies medially to radius Olecranon is at elbow end Radial notch faces laterally toward radius Sharp edge faces laterally towards radius Concave surface - space for muscles - faces forward Styloid process sort-of points medially
RE-ASSEMBLY Head HUMERUS Capitulum RADIUS ULNA Thumb Rt U LIMB Anterior surfaces
WRIST & HAND III Head of ulna Thumb Index finger/ Forefinger This is a view of the DORSUM (back) of the hand. The other is the PALMAR (palm) side Little finger/ Pinky Ring finger Middle finger
WRIST & HAND I Digits Knuckles Head of ulna CAUTION One thinks of the wrist as what one grips on someone, using one’s whole hand However, the wrist bones - carpals - are only those that lie under two fingers’ width just distal to the end of the ulna
HAND II: BONES Phalangeal bones Metacarpal bones 8 Carpal (wrist) bones
HAND II: BONES IV III II I V Phalanges (Phalangeal bones) 3 per finger Terminal Distal Middle Proximal 2 for the thumb Proximal Terminal Metacarpal bones 8 Carpal (wrist) bones
WRIST & HAND II Knuckles of the fist are the heads of the metacarpals However, the wrist bones - carpals - are only those that lie under two fingers’ width just distal to the end of the ulna Carpal bones But the carpal bones articulate with the radius: wrist is the radio-carpal joint Head of ulna
BROKEN ‘WRIST’ is a term to arouse caution The carpal bones articulate with the radius: wrist is the radio-carpal joint, so falling on the hand may break the distal radius However, the wrist bones - carpals - are only those that lie under two fingers’ width just distal to the end of the ulna Carpal bones And one bone in particular of these true wrist ones is sometimes fractured
MAINLY SPONGY BONE LOSScauses fractures in 1 Bones that are mostly spongy, e.g. vertebra compression fracture 2 Spongy part of long bones where leverage concentrates loading “Wrist” end of radius “Hip” fracture at neck of femur from falling on the hand
WRIST FOR COMMUNICATION Passing through the wrist are: Arteries All critical & vunerable, & with little muscle or fat to protect them Veins Nerves Tendons to flex Tendons to extend Some protection comes from running many structures on the palmar side Some of the carpal bones create a tunnel for more protection
LEFT CARPAL TUNNEL Schematic cross-section Flexor retinaculum - sheet of fibrous tissue roofing in the tunnel Ulnar artery Mediannerve Ulnar nerve Tendons to flex Tendons to extend CARPAL BONES outside tunnel, on dorsal side of wrist lubricated spaces/compartments for structures to glide in Discomfort of C-T syndrome from compromised median nerve
RADIAL ARTERY: Pulse Concave surface - space for muscles - faces forward & Radius lies laterally to ulna also protects vessels, e.g., radial artery Close to the wrist, where the muscles thin & give way to tendons, the pulse can be felt by pressing the artery against the bone with the finger tips
BRACHIAL ARTERY: Pulse Brachial refers to the arm Humerus The brachial artery lies protected on the medial side of the humerus Close to the elbow, where the muscles thin, the pulse can be felt by pressing the brachial artery against the humerus, or listened for with a stethoscope