Chapter 7 - The Skeleton Part II Flashcards
Pectoral Girdle
Shoulder; consists of the clavicle anteriorly and scapula posteriorly;
Clavicles
Collar bone; two one on each side; they are slender and take on the letter s, they extend on the superior thorax
a. Sternal end – cone shaped and attached to the sternum manubrium
b. Acromial end – flattened and this is the lateral end and it articulates with the scapula bone
c. Conoid tubercle – ligament anchoring point (better seen at inferior view)
d. Trapezoid line – ligament anchoring point (better seen at inferior view)
Scapulae
Second bone of pectoral girdle – aka shoulder blade – thin triangular flat bones and found on the dorsal surface of the rib cage they extend from ribs 2-7
a. Superior border – shortest and sharpest border
b. Medial border – aka the vertebral column towards the middle of the body
c. Lateral border – thickest border – aka the axillary boarder; furthers away from the body; it butts the armpit, this border ends superior into a small shallow fossa which is known as a glenoid cavity
d. Glenoid cavity – articulates with the humerus of the arm, forming the shoulder joint
e. Superior angle – where superior scapular border meets with the medial border
f. Lateral angle – where the superior scapular border meets the lateral border at the glenoid cavity
g. Inferior angle – medial and lateral borders meet and it moves as the arm is raised or lowered
h. Spine – found on posterior of the scapula and can be felt through the skin and it ends laterally as a part that is known as the acromion
i. Acromion – enlarged lateral ending of the spine, it looks like a triangular projection, it articulates with the acromional end of the clavicle forming the acromional joint
j. Coracoid process – anteriorly projecting from the superior border of the scapula and it looks like a bent finger. It helps anchor the biceps muscles
k. Infraspinous and supraspinous fossae – found on the posterior aspect of the scapula and both contain muscles
l. Subscapular fossa – anterior scapula, it’s a shallow concavity that’s formed by the entire anterior scapula surface
Humerus
Only bone of the arm and is a typical long bone; largest bone of the upper limp and it articulates with the scapula and the radius and ulna (forearm bones) at the elbow
i. Head – found on proximal end; it’s smooth and hemispherical and it joins the glenoid cavity
ii. Anatomical neck – slight constriction that’s found inferior to the head
iii. Greater and lesser tubercles – found just inferior to the anatomical neck and laterally placed is the greater tubercle and more medial will be the lesser tubercle
iv. Intertubercular sulcus – aka the bicipital groove; it separates the greater and lesser tubercles
v. Surgical neck – found distal to the tubercles most commonly fractured part of the humerus
vi. Deltoid tuberosity – midway down the shaft and found on the lateral side; its V shapes; its serves as an attachment sight for deltoid muscle
vii. Trochlea – found on distal end of humerus but on the medial aspect of the distal humerus – aka pulley (capitulum and trochlea are the condyles)
viii. Capitulum – found on distal end of humerus but on the lateral aspect of the distal humerus – ball shaped
ix. Medial and lateral epicondyles – found on the distal end and flank the pair of condyle
x. Olecranon and coronoid fossaes – found on posterior surface and found to be superior to the trochelea; coronoid fossa is on the anterior surface and superior to the trochelea. They let the corresponding processes of the ulna move and house the basic processing of the ulna as well
xi. Radial fossa – found laterally placed to the coronoid fossa and it receives the head of the radius when the head is flexed
Ulna
Makes up elbow- its slightly longer than the radius and it looks like monkey wrench, it is more medially placed of the two forearm bones
i. Olecranon and coronoid processes – olecranon is the elbow; coronoid process – promenaded processes that grip the trochlear forming a type of a hinge joint
ii. Trochlear notch – it’s a deep concavity which separates the olecranon and coronoid processes and contains the trochelear
iii. Radial notch – small depression on the lateral side of the coronoid process and this is where the ulna and radius articulate
iv. Head – found on the distal end and its knob like
v. Ulna Styloid process – medial to the head and contains ligaments for the wrist
Radius
Proximal end is thinner compared to its distal end which is wide (opposite of the ulna
i. Head – looks the head of a nail, found on the superior surface and the superior surface is concaved and it articulates with the capitulum; medially it articulates with the radial notch of the ulna
ii. Radial tuberosity – rough and found inferior to the head and it anchors the biceps muscles
iii. Ulnar notch – where the distal radius articulates with the ulna
iv. Radiual Styloid process – is laterally located and is a wrist ligaments anchoring site
Interosseous Membrane
Flat flexible ligament that connects theradius and the ulna along the entire length
Hand: Carpus
Carpus – consists of 8 carpal bones,
i. Carpals – 8 marble size short bones
A. Proximal – Scaphoid (both articulate with the radius) lunate, triquetral, and pisiform (pinky)
B. Distal – Trapezium, trapezoid, capitate, and hamate
Hand: Metacarpus
Metacarpus – make up palm, like spokes on bikes, 5 small long bones
i. Metacarpals
A. 1 through 5 – thumb 1 – pinky 5
B. Bases – articulate with carpal bones proximally
C. Heads – bulbous in shape and articulate with proximal phalanges and help form knuckles
Hand: Phalanges
Phalanges – digits of the upper limp
i. 1 through 5 – thumb to pinky
ii. Proximal, middle, and distal phalanges (14 total)
iii. Pollex – thumb – has two bones proximal and distal NO middle
Coxal Bones
Hip bones that help from the pelvic girdle, each coxal bone is large irregularly shaped hip bone and consists of 3 bones which are fused together
Ilium
Large flaring bone which forms the superior region of the coxal bone
i. Body – found to be inferior to the ala
ii. Ala – superior wing like projection
iii. Iliac crest – thicken superior margin of the ala and serves for muscle attachment
iv. Anterior and posterior superior iliac spines – endings of each iliac crest
v. Anterior and posterior inferior iliac spines – located below the superior ones and less prominate
vi. Greater sciatic notch – found inferior to the posterior inferior iliac spine and this is where the Ilium indents deeply; allows for the sciatic nerve to pass though and reach to the thigh
vii. Gluteal surface – broad and found on the posterior lateral surface and serves for muscle attachment
viii. Iliac fossa – medial surface of the iliac ala
ix. Auricular surface – found posteriorly placed, that’s roughened and it articulates with the same named surface of the sacrum forming the sacral iliac joint
Ischium
Forms the posterior inferior part of the hip bone
i. Body – body joins the ilium
ii. Ramus – found to be thinner than the body and joins the pubis bone
iii. Ischial spine – attachment point for the sacral spinus ligament
iv. Lesser sciatic notch – found inferior to the spine, nerves and blood vessels pass though it
v. Ischial tuberosity – found on the inferior surface, its rough and grossly thickened appearance, it bears the weight when we’re sitting
Pubis
Pubic bone, it forms the anterior portion of the hip bone
i. Body – forms the anterior portion of the hip bone
ii. Superior and inferior rami – flattened medial body
iii. Pubic crest – thickened area that’s found on the anterior boarder
iv. Pubic symphysis and pubic arch – bodies for the 2 pubic bones join to form the midline pubic symphysis joint and inferior to this joint the pubic rami (angel forming the inverted V shaped arch which is known as the pubic arch
Articulated Pelvis
a. Acetabulum – found on the lateral surface of the coxal bones, it’s a deep hemispherical socket where all 3 bones come together and fuse, it receives the head of the femur and helps form the hip joint
b. Obturator foramen – large opening in the hip bone and its formed as the two rami of the pubic bone run laterally to join with the body and ramius of the ischium, blood vessels and nerves pass though; its nearly closed by a fibrous membrane
c. Pelvic brim and pelvic inlet – brim is a continues oval ridge that runs from the pubic crest though the arcuiate line; the inlet is found at the brim and is formed by the brim
d. False pelvis – superior portion to the pelvic brim it’s bounded by the ala of the ilia laterally and the lumbar vertebrae posteriorly (it’s really part of the abdomen)
e. True pelvis – found inferior to the pelvic brim and its entirely surrounded by bone, it contains pelvic organs, the dimension (particularly of the inlet and outlet) are critical to child birth (measured by OBGYN)
f. Pelvic outlet – found at the inferior margin of the true pelvis, its bounded anteriorly by the pubic arch laterally by the Ischia and posteriorly by the sacrum and coccyx bone
