177 medical assisting administrative and clinical procedures (5e) chapter 24 the skeletal system

After completing this chapter, you will be able to: List the functions of skin, explain the role of skin in regulating body temperature, describe the layers of skin and the characteristics of each layer, explain the factors that affect skin color, list the accessory organs of skin and describe their structures and functions.

The Skeletal

System

Learning Outcomes (cont.)

24.1 Describe the structure of bone tissue

24.2 Explain the functions of bones

24.3 Compare intramembranous and

endochondral ossification

24.4 Describe the skeletal structures and one

location of each structure

Learning Outcomes (cont.)

24.5 Locate the bones of the skull

24.6 Locate the bones of the spinal column

24.7 Locate the bones of the rib cage

24.8 Locate the bones of the shoulders, arms,

and hands

Learning Outcomes (cont.)

24.9 Locate the bones of the hips, legs, and feet

24.10 Describe the three major types of joints and

give examples of each

24.11 Describe the common diseases and

disorders of the skeletal system

• Arms and legs

• Pectoral girdle

• Pelvic girdle

Spongy (Cancellous) Bone

Bone Structure (cont.)

• Structures within compact bone

Bone Structure (cont.)

Bone Structure (cont.)

• Short bones

• Flat bones

• Irregular bones

• Sesamoid bones

Gender Differences in Skeletal Structure

Matching:

Holes in the matrix that contain

osteocytes

Made of inorganic salts, collagen

fibers, and proteins; between

Functions of Bones

• Give shape to body parts

• Support and protect soft

structures

• Function in body movement

• Red bone marrow – hematopoiesis

• Store calcium

Apply Your Knowledge

ANSWER: Every cell in the body needs calcium, so the

body must have a large supply readily available.

Why is it important for the bones to store calcium?

Bone Growth

• Ossification

• Intramembranous ossification

– Bones begin as tough, fibrous membrane

– Osteoblasts turn the

membrane to bone

• Endochondral ossification

– Bones begin as cartilage models

– Diaphysis ~ primary ossification center

Diaphysis

Bone Growth (cont.)

• Endochondral ossification

– Epiphysis ~ secondary ossification center

– Epiphyseal disc ~ cartilage between epiphysis and diaphysis

Bone Growth (cont.)

Building Better Bones

• Bone – healthy diet

Building Better Bones (cont.)

• Bone-healthy lifestyle – avoid smoking

and alcohol

• Bone tests

– Bone density tests

– Bone scan

Apply Your Knowledge

What are the two types of bone growth?

ANSWER: Intramembranous ossification, in which

bones begin as tough membrane and are turned to

bone by osteoblasts, and endochondral ossification, in

which primary ossification occurs in the diaphysis of

the bone and secondary ossification occurs in the

epiphysis.

Good Job!

Bony Structures

• Bones are designed with

– Projections and processes

– Depressions and hollows at

articulations

– Openings for blood vessels

and nerves

Bony Structures (cont.)

Term Definition

Condyle A rounded process that usually

articulates with another bone

Epicondyle A projection situated above a condyle

Foramen An opening through a bone that is

usually a passageway for blood vessels, nerves, or ligaments Fossa A relatively deep pit or depression

Bony Structures (cont.)

Term Definition

Process A prominent projection on a bone

Suture An interlocking line of union between

bonesTrochanter A relatively large process

Tubercle A small, knoblike process

Tuberosity A knoblike process, usually larger than

a tubercle

Apply Your Knowledge

Match the following:

_ Epicondyle A A relatively deep pit or depression

_ Fontanels B An interlocking line of union between bones

tubercle

_ Tuberosity F A prominent projection on a bone

The Skull

• Two bone types – cranial and facial

• Infant skulls

– Bones not completely formed

– Fontanels – tough membranes

– Sutures

The Skull (cont.)

– Sphenoid and ethmoid bones

The Skull (cont.)

• Facial bones

– Mandible ~ lower jaw

– Maxillae ~ upper jaw

– Zygomatic

• Cheekbones

• Fused nasal bones form bridge of nose

– Palatine ~ hard palate

– Vomer ~ divides nasal cavity Click to see

Skull

Apply Your Knowledge

Match the bones of the skull:

cavity

The Spinal Column

The Spinal Column (cont.)

• Cervical vertebrae

– Smallest and lightest

– Located in the neck

– Atlas

– Axis

• Thoracic vertebrae

– Posterior attachment for ribs

• Lumbar vertebrae

– Small of the back – Bear most weight

The Spinal Column (cont.)

Apply Your Knowledge

Identify the sections

of the spinal column

and give the

Cervical – 7

ANSWER:

Right!

The Rib Cage

The Rib Cage (cont.)

• Ribs

– All are attached posteriorly to thoracic

vertebrae – True – 1st 7 pairs

– False – pairs 8, 9, and 10

– Floating – pairs

To ribcage

The Rib Cage (cont.)

Back

Apply Your Knowledge

True or False:

_ The sternum forms the front middle portion of the rib cage.

_ The xiphoid process is a boney tip of the sternum.

_ The true ribs are the first five pairs of ribs

_ False ribs attach to the costal cartilage of rib pair seven.

_ Floating ribs attach to the xiphoid process.

Bones of the Shoulders, Arms, and Hands

• Shoulders

– Clavicles ~ collar bones

– Scapulae ~ shoulder blade

• Arm bones

– Humerus – Radius – Ulna

• Hand

– Carpals ~ 8– Metacarpals ~ 5

– Phalanges ~ 14

• 3 per finger

• 2 per thumb

Apply Your Knowledge

Match the following:

Bones of the Hips, Legs, and Feet

Bones of the Hips, Legs, and Feet (cont.)

Bones of the Hips, Legs, and Feet (cont.)

• Bones of the foot

Apply Your Knowledge

Match the following:

– Between cranial bones

and facial bones– Sutures

Joints (cont.)

• Synovial joints

– Covered with hyaline

cartilage– Fibrous joint capsule

– Freely movable

– Ligaments hold

bones together

Apply Your Knowledge

Match the following:

A Fibrous joints B Cartilaginous joints C Synovial joints

Between cranial bones and facial bones

Covered with hyaline cartilage

Skeletal System (cont.)

• Bursitis – inflammation of the bursa

• Ewing sarcoma family of tumors (ESFT)

– Primarily affect bone

– Usually lower extremities

• Gout – deposits of uric acid crystals in

joints

Skeletal System (cont.)

• Kyphosis – humpback

• Lordosis –swayback

• Osteogenesis imperfecta – brittle-bone disease

• Osteoporosis – thin, porous bones

Skeletal System (cont.)

• Osteosarcoma – bone cancer from osteoblasts

• Paget’s disease – bones enlarge, become

deformed, and weak

• Scoliosis – an abnormal S-shaped curvature of

the spine

Apply Your Knowledge

Osteoarthritis is a degenerative joint disease

that primarily affects weight-bearing joints.

Rheumatoid arthritis chronic systemic

inflammatory disease of smaller joints and

surrounding tissues; it is thought to be an

autoimmune disease.

What is the difference between osteoarthritis and

rheumatoid arthritis?

Nice Work!

In Summary

24.1 Bones consist of the following substances:

osteons or Haversian systems; bone matrix between osteocytes (bone cells); collagen fibers and proteins; the lamella; and canaliculi

The skeleton consists of long bone, short bones, flat bones and irregular bones

The diaphysis is the shaft of the long bone The epiphysis is an end of a long bone Articular

cartilage covers the end of the long bones The endosteum lines the medullary cavity The

periosteum is the membrane surrounding the diaphysis

In Summary

24.2 Bone functions include giving shape to body

parts, protecting soft structures of the body, and assisting in movement The red bone marrow is responsible for hematopoiesis

Bones also store calcium

24.3 Bones grow through the two types of

ossification: intramembranous ossification and endochondral ossification The cartilage plate between the diaphysis and the

epiphysis allows for growth of the long bone

In Summary (cont.)

24.4 Skeletal structures include the following:

condyles, crests, epicondyles, foramina, fossae, heads, processes, sutures,

trochanters, tubercles, and tuberosities

24.5 The major bones of the skull are the frontal,

parietal, temporal, and occipital bones The skull also contains the fontanels, the mastoid processes, sphenoid,ethmoid, and ear

ossicles The facial bones include the mandible, maxillae, zygomatics, nasal and palatine bones, and the vomer

In Summary (cont.)

24.6 The spinal column includes cervical, thoracic,

and lumbar vertebrae; the sacrum; and the coccyx

24.7 There are 12 pairs of ribs, a sternum, and the

xiphoid process

24.8 Each upper extremity includes the clavicle,

scapula, humerus, radius, ulna, carpals, metacarpals, and phalanges

In Summary (cont.)

24.9 The bones of the hip, leg, and foot include

the coxal bones, the femur, patella, tibia, fibula, metatarsals, tarsals, and phalanges

24.10 The three joint types are fibrous joints,

cartilaginous joints, and synovial joints A synovial joint consists of hyaline-covered bones held together by a fibrous joint

capsule, which is lined by a synovial membrane that secretes synovial fluid

Ligaments hold the bones of these joints together

In Summary (cont.)

24.11 There are many common diseases and

disorders of the bones and the skeletal system with varied signs, symptoms, and treatments Examples include arthritis, bursitis, EFT, gout, kyphosis, lordosis, and scoliosis, as well as osteoporosis and

osteosarcoma

Rigid, the skeleton of habit alone upholds the human frame.

~ Virginia Woolf

End of Chapter 24