Crafton Hills College Human Anatomy & Physiology 150

APPENDICULAR Skeleton (Ch. 7) A. General Characteristics 1. Appendicular skeleton: Skeleton of appendages (limbs) & girdles; that attaches them to axial skeleton. 2. Responsible for: Movement (walk/run, etc.) and our ability to manipulate our environment B. Pectoral Girdles (Shoulder Girdles) 1. General Descriptions a. Pectoral girdles: Consist of anterior clavicles and posterior ____________ b. Attach upper limbs to the axial skeleton (maximum R.O.M.) c. Attachment points for muscles that move upper limbs 2. Clavicles (Collarbones) a. Slender, doubly curved long bones lying across the superior thorax b. Acromial (lateral) end articulates w/scapula, and Sternal (medial) end articulates w/sternum 3. Scapulae (Shoulder Blades) a. Scapulae are triangular, flat bones; Dorsal surface of rib cage; Between 2nd and ____ ribs b. Three borders and three angles c. Major markings: Suprascapular notch, Supraspinous and Infraspinous fossae, spine, Acromion, and the Coracoid process C. Upper Limb 1. General Descriptions a. Upper limb: Consists of the arm (brachium), forearm (antebrachium), and hand (manus) 2. Arm (humerus) a. General Descriptions i. Humerus: Only bone of the arm ii. Articulates with scapula at the shoulder, and the radius & ulna at the elbow b. Major markings i. Proximal humerus:

Head, anatomical and surgical necks, greater and lesser tubercles, and the intertubercular groove

ii. Distal humerus:

Capitulum, trochlea, medial and lateral epicondyles, and coronoid and olecranon fossae

iii. Medial portion:

Radial groove and ____________ process

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3. Forearm (antebrachium) a. General Description i. Bones of forearm are the radius and ulna ii. Articulate proximally with humerus; distally with wrist bones (carpals) iii. Articulate with each other proximally and distally at small radioulnar joints iv. Interosseous membrane connects the two bones along their entire length b. Ulna i. Medial bone in forearm (anatomical position); Slightly longer than radius ii. Forms major portion of elbow joint (along with the humerus) iii. Major markings:

Olecranon and coronoid process, trochlear notch, radial notch, and _____________ process

c. Radius i. Lateral bone of forearm (opposite ulna); thin proximal end & wide distal end ii. Superior Head: Articulates with capitulum of the humerus iii. Medial Head: Articulates w/radial notch of ulna iv. Major markings:

Radial tuberosity, ulnar notch, and styloid process

4. Hand (___________) a. General Description i. Contains Wrist bones (carpals), Palm bones (metacarpals), Finger Bones (phalanges) b. Carpus (Wrist) i. Consists of eight bones in 2 rows 1) Proximal: Scaphoid, lunate, triquetral, and pisiform proximally 2) Distal: Trapezium, trapezoid, capitate, and hamate distally c. Metacarpus (Palm) i. Palm formed from five metacarpal bones (numbered 1-5) radiate from wrist 1) Base of metacarpals articulate with the carpals proximally, each other medially and laterally 2) Heads articulate _______________ with the phalanges d. Phalanges (Fingers) i. 14 miniature long bones ii. Fingers (digits) are numbered 1-5; thumb (pollex) is #1 iii. Each finger (except the thumb) has three phalanges - distal, middle, and proximal iv. Thumb: NO middle phalanx

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D. Pelvic Girdle (Hip) 1. Definition a. Hip formed by a pair of hip bones (os coxae, or coxal) b. Bony Pelvis: Combination of sacrum, coccyx, and os coxae 2. Function a. Attaches lower limbs to the __________ skeleton with body's strongest ligaments) b. Transmits weight of the upper body to the lower limbs c. Supports visceral organs of the pelvis 3. Os Coxae a. Ilium i. Large flaring bone that forms superior region of the coxal bone ii. Parts: Body and ala (superior, posterior winglike portion) iii. Gluteal Surface: Broad posterolateral surface iv. Auricular surface articulates with the sacrum (sacroiliac joint) v. Major markings:

Iliac __________, four spines, greater sciatic notch, iliac fossa

b. Ischium i. Posteroinferior part of the hip bone ii. Thick body articulates with the ilium, and the thinner ramus articulates with the pubis iii. Major markings:

Ischial spine, lesser sciatic notch, and the ischial tuberosity

c. Pubis i. Forms the anterior portion of hip bone ii. Articulates with the ischium and the ilium iii. Major markings:

Pubic tubercle, pubic arch, pubic symphysis, and obturator foramen (along with ischium)

d. Gender-based Differences i. Female pelvis 1) Tilted forward, adapted for childbearing 2) True pelvis defines birth canal 3) Cavity of true pelvis is broad, shallow, and has greater capacity ii. Male pelvis 1) Tilted ________ forward 2) Adapted for support of heavier male build and stronger muscles 3) Cavity of true pelvis is narrow and deep

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Gender-based Differences of the Pelvic Girdle: Male vs. Female Characteristic Bone thickness

Female Lighter, thinner, and smoother

Male Heavier, thicker, and more prominent markings

Pubic Arch/Angle 80o - 90o

50o - 60o

Acetabula

Small; farther apart

Large; closer together

Sacrum

Wider, shorter; sacral curvature is

Narrow, longer; sacral promontory more

accentuated

ventral

More movable; straighter

Less movable; curves ventrally

Coccyx

E. Lower Limb 1. General Description a. Three segments of the lower limb: Thigh (femur), Leg (tibia & fibula), and Foot b. Carries weight of erect body (weight/force is dramatically increased when one jumps or runs) 2. Thigh (Femur) a. Sole bone of thigh; _______________ and strongest bone in the body b. Articulates proximally with the hip; Distally with the tibia & fibula c. Major markings:

Head, greater and lesser trochanters, lateral and medial condyles and epicondyles, linea aspera, patellar surface

3. Leg (Tibia & Fibula) a. General Characteristics i. Tibia and Fibula form the skeleton of the leg -- Connected to each other by interosseous membrane ii. Articulation 1) Proximally with __________ 2) Distally with ankle bones distally 3) Laterally with each other via immovable tibiofibular joints b. Tibia i. Bears weight of body: Transmits weight from femur to the foot ii. Major markings:

Medial and lateral condyles, tibial tuberosity, anterior crest, medial malleolus

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c. Fibula i. Thinner, sticklike bone with slightly flared ends located laterally to the tibia ii. Major markings:

Head and lateral malleolus

4. Foot (Tarsals, metatarsals, digits) a. General Description i. Parts:

_____________, metatarsals, and the phalanges (toes)

ii. Supports body weight; Acts as lever to propel the body forward (walking & running) b. Tarsals (Tarsus) i. Seven bones forming posterior half of the foot ii. Talus and the Calcaneus bear the majority of the body's weight iii. Talus articulates with tibia & fibula superiorly, and the calcaneus inferiorly iv. Other tarsal bones:

Cuboid and navicular, and the medial, intermediate, and lateral cuneiforms (see figure in atlas/text)

c. Metatarsals i. Five (1-5) long bones; Articulates with proximal phalanges ii. "Ball of the Foot":

Enlarged head of metatarsal 1

iii. Calcaneus –

Forms the _________ of the foot

–

Articulates with talus on its superior surface

–

Calcaneal (______________) tendon (of calf muscles) attaches here

d. Phalanges i. The 14 bones of the toes ii. Each digit has three phalanges except the hallux, which has no middle phalanx e. Arches of the Foot i. Characteristics –

3 arches maintained by interlocking foot bones & strong ligaments

–

Arches allow the foot to hold up weight

ii. Lateral longitudinal - From heel to toe, outside iii. Medial longitudinal - From heel to toe, inside iv. Transverse - Obliquely from one side to the other F. Fetal Skull 1. Fontanels a. Unossified remnants of fibrous membranes between (connecting) fetal skull bones b. Names:

Anterior, Posterior, Mastoid, and Sphenoid

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