Chapter 8 Anatomy and Physiology

Bones of the appendicular skeleton

- Pectoral (shoulder) girdle (clavicle and scapula) -Upper limb (Extremity) 30 bones in each upper limb (Humerus, ulna and radius, 8 carpals in wrist, 5 metacarpals in the palm, 14 phalanges in the hand) - Pelvic (Hip) girdle (two hip bones also called coral or pelvic bones or os coxa, Ischium, Pubis, ilium) - Lower Limb (Extremity) each lower limb has 30 bones (femur, patella, tibia and fibula, 7 tarsals in the ankle, 5 metatarsals in the metatarsus, and 14 phalanges in the foot)

The _____ is a fossa formed by the ilium, ishchium, and pubis which with the femoral head forms the ________ joint

Acetabulum; coxal

Principal differences between female and male pelves

Female General structure: shallow False (greater Pelvis) Shallow Pelvic brim (inlet): wide and more oval Acetabulum: Small and faces anteriorly Obturator foramen: Oval Pubic arch: greater than 90 degree angle Iliac crest: less curved Ilium: less vertical Greater sciatic notch: wide almost 90 degrees Sacrum: Shorter, wider, and less curved anteriorly Pelvic outlet: wider Ischial TuberosityL Shorter, farther apart, and more medially projecting Male General structure: heavy and thick False (greater) pelvic: Deep Pelvic brim (inlet): Narrow and heart-shaped Acetabulum: Large and faces laterally Obturator foramen: Round Pubic arch: less than 90 degree angle Iliac crest: more curved Ilium: more vertical Greater sciatic notch: Narrow (about 70 degrees; inverted V) Sacrum: longer, narrower, and more curved anteriorly Pelvic outlet: narrower Ischial Tuberosity: longer, closer together, and more laterally projecting

Surface markings of the appendicular skeleton (Lower limb)

Femur - head: proximal, rounded articulation with the acetabulum - fovea: Depression in head where a stabilizing ligament attaches - Neck: constriction distal to the head - greater trochanter: Process that projects laterally from the junction of the neck with the shaft - Lesser trochanter: Process on posterior, medial surface of femur - Intertrochanteric line: Anterior line between greater and lesser trochanter - Interochanteric crest: More prominent ridge on the posterior surface - Gluteal tuberosity: inferior to intertrochanteric crest on lateral side Patella - base: broad superior attachment for quadriceps tendon -Apex: inferior somewhat broad point Tibia: - Medial and lateral condyles: round expanded process with flat articular surfaces - Tibial tuberosity: roughened prominence on anterior surface for attachment of patella ligament Fibula: - Head: Articulates inferior and slightly posterior to the lateral tibial condyle - Lateral malleolus: Distial epiphysis provides stability to the ankle joint by preventing medial sliding of tibia across the talus Tarsal Bones: -Talus: Transmits weight from tibia to foot, its articulation with the tibia is the smooth superior surface, the trochlea - calcaneus: largest tarsal bone forms the heel, transmits most of the weight when standing - Cuboid bone: Articulates with anterior surface of calcaneus - Navicular bone: Articulates with anterior surface of talus - Cuneiform bones: three wedge-shaped bones, medial cuneiform, intermediate cuneiform, and later cuneiform articulate with anterior surface of navicular bone

What is the function of the interosseous membrane between the ulna and radius?

Joins the shafts of two bones

In comparison to the male pelvis, the female pelvis is not

Larger in the acetabulum

Surface markings of the appendicular skeleton (Pelvic Girdle)

Pelvic Girdle - Acetabulum: curved surface that articulates with the head of the femur, within the acetabulum: *Lunate surface: smooth curves, c-shaped surface, an anterior and inferior gap in this surface is called the acetabular notch *Acetabular fossa: the dished-out space enclosed by the lunate surface Ilium - Arcuate line: line on the medial side marks the beginning of the broad superior expansion -Inferior illica notch: Notch inferior to the anterior inferior iliac spine - Anterior inferior iliac spine: Process on anterior border of ilium - Anterior superior iliac spine: process on anterior border of ilium Iliac crest: curving superior border of ilium - Oisterioir superior iliac spine: Process at the end of the iliac crest - Posterioir inferior iliac spine: Rounded inferior process on posterior border of ilium Greater sciatic notch: Notch through which the sciatic nerve passes - iliac fossa: Concave medial surface of ilium - Auricular surface: ear-shaped roughened surface that contributes to the sacroiliac joint - Iliac tuberosity: roughened process superior to the articular surface where the ligaments that stabilize the sacroiliac joint attaches Ischium - Ischial spine: Process below grater sciatic notch -lesser sciatic notch: Interior to ischial spine - Ischial tuberosity: roughened projection on which the body weight is borne when seated - Ischial ramus: narros brach that fuses with the inferior branch of the pubis Pubis - Inferior ramus: Branch that fuses with the ischial ramus - Superior ramus: contributes to the acetabulum, features on it include: *Pubic tubercle: Process on anterior and superior part *Pectineal line: Line that extends from pubic tubercle to arcuate line *Pubic crest: roughened ridge that extends medially from pubic tubercle *Obturator foramen: "opening" surrounded by ischial and pubic rami and closed by connective tissue in the living person -*Obturator groove: Groove on superior ramus that permits passage of blood vessels and nerves

Why are the false and true pelves important clinically?

Pelvimetry is the measurement of the size of the inlet and outlet of the birth canal, which may be done by ultrasonography or physical examination. Measurement of the pelvic cavity in pregnant females is important because the fetus must pass through the narrower opening of the pelvis at birth. A cesarean section is usually planned if it is determined that the pelvic cavity is too small to permit passage of the baby. True and false pelves are clinically important for pelvic exams and childbirth.

Which joint consists of a fibrocartilage pad that joins the two pubic bones anteriorly?

Pubic symphysis

Which of the following bones articulate at the glenohumeral joint?

Scapula and humerus

Surface markings of the appendicular skeleton (scapula)

Scapula: - Glenoid cavity: cup shaped. Supported by the lateral angle -Coracoid Process: Smaller anterior projection - Suprascapular notch: An indentation medial to the base of the coracoid process - Acromion: Larger posterior process. it is continuous with the scapular spine, a ridge that extends to the medial border - Subscapular fossa: The concave anterior surface on the body of the scapula - Supraspinous fossa: The flat surface superior to the scapular spine - Infraspinous fossa: the flat surface interior to the scapular spine Upper Limb: (Humerus) -Greater tubercle: Large projection lateral to the head

Which lower leg bone is an actual weight-bearing bone?

Tibia

What is the medial end of the clavicle called?

Sternal end

Which of the following is NOT a way that the skeletal system contributes to homeostasis?

Stores and releases sodium ions

Most people can see and feel the bony prominences on the medial and lateral sides of the ankles. What bone features and bones form these two prominences?

The medial malleolus of the tibia, and the lateral malleolus of the fibula

False Pelvis

The portion of the bony pelvis superior to the pelvic brim. It is bordered by the lumbar vertebrae posteriorly, the upper portions of the hip bones laterally, and the abdominal wall anteriorly. The space enclosed by the false pelvis is part of the lower abdomen; it contains the superior portion of the urinary bladder (when it is full) and the lower intestines in both genders, and the uterus, ovaries, and uterine tubes of the female

True Pelvis

The portion of the bony pelvis that is inferior to the pelvic brim. It has an inlet, and outlet, and a cavity and is bound by the sacrum and coccyx posteriorly., inferior portions of the ilium and ischium laterally, and the pubic bones anteriorly. Surrounds the pelvic cavity. Contains the rectum and urinary bladder in both genders, the vagina and cervix of the uterus in females, and the prostate in males.

Which of the following structures on the ulna receives the trochlea of the humerus?

Trochlear notch

True or false At birth, each hip bone is composed of three separate bones which aren't completely fused until the person is in their early 20's.

True

True or false The coracoid process of the scapula does not articulate with any bone, but it is an attachment site for tendons and ligaments.

True

Surface markings of the appendicular skeleton (Upper limb)

Upper Limb: Humerus - Greater tubercle: Large projection lateral to the head - lesser tubercle: smaller projection on the anterior and medial surface of the epiphysis - inter tubercular gore: Groove separating the greater and lesser tubercles - anatomical neck: Constriction distal to the head of the humerus - Surgical neck: Constriction distal to tubercles and head of humerus, frequent site of fractures - Deltoid Tuberosity: Elevated, roughened surface on the lateral side of the shaft, deltoid muscle attaches here -Diaphysis (Shaft): the proximal shaft is cylindrical, the distal shaft flares to form a flatter triangular portion - Medial and lateral epicondyles: the flared distal ends of the humerus on either side of the articular surface, muscles attach here -Condyle: The inferior articular surface of the humerus that articulates with the ulna and the radius. The articular condylar surface is divided into *Trochlea: Spool-shaped medial portion that articular with the ulna *Capitulum: Rounded lateral portion that articulates with the head of the radius - Coronoid Fossa: Accepts coronoid process on the anterior surface during flexion - Olecranon fossa: Accepts olecranon of ulna during extension - Radial fossa: accepts head of radius during flexion Ulna - Olecranon: Superior and posterior portion of the epiphysis that forms the point of the elbow - Trochlear notch: Anterior portion that interlocks with the groove of the trochlea - Radial notch: Lateral to the coronoid process, this accommodates the radial head - Ulnar head: Disc-shaped distal part - Styloid Process: Short process posterior to the ulnar head Radius - Radial head: Disc-shaped head articulates with the capitulum of the humerus - Radial tuberosity: the attachment site for the biceps brachii muscle - Distal extremity: Distal portion of the radius that forms the proximal side of the wrist joint, includes: *Styloid process- Process on lateral side of distal extremity stabilizes the wrist joint *Ulnar notch of radius: Notch on medial side articulates with the ulnar head Carpal bones - Proximal carpal bones: *Scaphoid (boat-like) bone: adjacent to styloid process of radius *Lunate (moon-like) bone: Articulates with radius along with the scaphoid *Triquetrum (Triangular) bone: Shaped like a pyramid *Pisiform (pea-shaped) bone: small bone that lies anterior to the triquetrum -Distal Carpal bones: *Trapezium: froms a proximal articulation with the scaphoid *Trapezoid bone: Wed-shaped bone that also has a proximal articulation with the scaphoid *Capitate (having a head) bone: largest carpal bone *Hamate (Hooked) bone: Hook-shaped bone)

The head of the femur articulates with what feature of the hip bones to form the hip (coxal) joint?

acetabulum

Which of the following is the correct sequence of bones of the lower limb, from proximal to distal ends?

femur, patella (kneecap), tibia and fibula, tarsals, metatarsals, phalanges

The clavicle articulates with which of the following structures to form the sternoclavicular joint?

manubrium