Ch 8 - Skeletal System

Question 1

What are the two major divisions of the skeletal system?

Answer 1

Axial and Appendicular

Question 2

What does the axial skeleton consist of?

Answer 2

80 bones skull, hyoid bone, auditory, vertebral column, sternum and ribs
Lie along the longitudinal axis of the body

Question 3

What does the appendicular skeleton consist of?

Answer 3

126 bones AND muscles

Question 4

What are the functions of the skeletal system?

Answer 4

Protection
Skull protects the brain from injury and the ribs and vertebra protect viscera, such as the heart and lungs
Support
Allows us to sit, stand, and move by the attachment of muscles to bones
Storage
Bone acts as a reservoir for over 99 percent of the calcium in our body.
Production
White and red blood cells are produced by red bone marrow contained within bone.

Question 5

What are two types of bone tissue?

Answer 5

Cancellous (spongy) bone -Spaces filled with red bone marrow.
Compact bone

Question 6

What are osteons?

Answer 6

Osteons (Haversian systems) are the fundamental unit.
Each osteon consists of a long, cylindrical tube of concentric layers of bone called lamellae.
Inside the lamellae are lacunae where osteocytes can be found
Central canal is lined with the endosteum and contains blood vessels and nerves.
Canaliculi are smaller canals which run perpendicular to the central canal. They carry blood vessels and nerves to lamellae and lacunae

Question 7

What are the three types of bone cells and what do they do?

Answer 7

Osteoblasts: immature bone cells, responsible for mineralizing the bone matrix
Osteocytes: mature bone cells
Osteoclasts: tear down bone for remodeling and cause the release of calcium

Question 8

What is the bone growth process called?

Answer 8

ossification or osteogenesis.

Question 9

What are the two types of ossification?

Answer 9

Intramembranous

Endochondral

Question 10

What happens in intramembranous ossification?

Answer 10

Bones begin as tough, fibrous membranes that are replaced by a bone matrix that is produced by osteoblasts.
Matrix is made up of calcium, phosphate, collagen fibers, and water.
Collagen fibers give bone its flexibility and the minerals give bone its strength.
Other factors essential to bone growth
Vitamins A for osteoblast stimulation and C for collagen synthesis , growth hormone, insulin, and thyroid hormone.
All bones of the skull but the lower jaw is formed by intramembraneous ossification.

Question 11

What happens in endochondral ossification?

Answer 11

Bones start out as models made of hyaline cartilage.
Common in long bones such as femur
Osteoblasts form a bone “collar” around the diaphysis and replace the cartilage model.
Ossification centers is the area where ossification first begins is the primary ossification center
Each end or epiphysis are the secondary ossification centers. Some bones such as the vertebrae have more than two

Question 12

What is the medullary cavity?

Answer 12

It is in the center of long bones and is initially filled with red bone marrow, involved in hematopoiesis - RBC formation.

Question 13

What is the epiphyseal plate?

Answer 13

growth plate
Between the epiphysis and diaphysis
Between 18 and 25 years of age, made of hyaline cartilage is replaced by bone, becoming the epiphyseal line and the bone is no longer capable of growing in length

Question 14

What are osteoclasts?

Answer 14

Cells that tear down bone
Regulated by parathyroid hormone
Bone remodeling is a balance between tearing down and building up bone.
Increased demand for calcium, osteoclastic activity will increase
Decreased demand for calcium, osteoblastic activity will increase

Question 15

What are flat bones?

Answer 15

Thin and consist of a layer of spongy bone between two layers of compact bone
Sternum, ribs, scapulae, and cranial bones

Question 16

What are long bones?

Answer 16

Greater in length than width
Mostly compact bone, but their epiphyses are spongy bone
Femur, tibia, fibula, humerus, radius, ulna, and phalanges

Question 17

What are short bones?

Answer 17

Cuboidal in shape
Spongy bone with just a thin outer layer of compact bone
Carpals and tarsals

Question 18

What are irregular bones?

Answer 18

Variety of shapes

Vertebrae, coxal, some facial bones, and the calcaneus

Question 19

What are seasmoid bones?

Answer 19

Resemble sesame seeds

Patella (kneecap) and pisiform

Question 20

What is diaphysis?

Answer 20

Tubular structure with a thick collar of compact bone surrounding a space called the medullary cavity
In children, this is the location of red bone marrow and is responsible for hematopoiesis
In adults, red bone marrow is replaced by yellow bone marrow
Except for skull, ribs, vertebra, and pelvis

Question 21

What is epiphysis?

Answer 21

At each end of a long bone
Expanded area consisting of a thin layer of compact bone surrounding more abundant cancellous bone
Covering each epiphysis is articular cartilage of the hyaline cartilage. It is smooth and helps in frictionless movement of joints.

Question 22

What is periosteum?

Answer 22

Membrane surrounds the diaphysis
Dense fibrous connective tissue
Blood vessels and nerves penetrating it
Responsible for “growing pains” during adolescence

Question 23

What two main types of bone markings?

Answer 23

Projection- Grow out

Depressions- Indent the bone

Question 24

What is the rib cage formed of?

Answer 24

Formed by sternum and 12 pairs of ribs

Question 25

What is the sternum?

Answer 25

Sternum is also called the breastbone Made up of three bones From most superior to inferior they are the manubrium, the body, and the xiphoid process Anteriorly, the clavicles and most of the ribs attach to the sternum Posteriorly, the ribs articulate with the vertebra

Question 26

What does the spinal column consist of?

Answer 26

``` 7 cervical vertebrae 12 thoracic 5 lumbar sacrum coccyx ```

Question 27

What are the 4 major curvatures to the spine?

Answer 27

cervical, thoracic, lumbar and pelvic

Question 28

What is the cervical vertebrae and what does it consist of?

Answer 28

Located in the neck 1st - called atlas/C1 - helps to turn your head, 2nd is axis/c2 Have 3 foramina - 2 transverse and single vertebral foreman . Vertebral artery , vein, nerves travel through transvers Spinal cord travels through foramen

Question 29

What is the lumbar vertebrae and what does it consist of?

Answer 29

Biggest and sturdiest - support body weight

Question 30

What are clavicles?

Answer 30

Clavicles or collarbones | Slender in shape and each articulates with the sternum and scapula

Question 31

What are Scapulae?

Answer 31

Thin, triangular shaped flat bones located on the dorsal surface of the rib cage. Each scapula joins with the humerus and a clavicle

Question 32

What is the humerus?

Answer 32

Upper part of the arm Proximally it articulates with the scapula and distally with the radius and the ulna Head of the humerus articulates with the glenoid fossa of the scapula. Shoulders can become dislocated because the fossa is very shallow

Question 33

What is the radius?

Answer 33

Radius is the lateral bone of the forearm In anatomical position, it is on the same side of the arm as the thumb Proximally it joins with the humerus and the ulna Distally with the carpal bones

Question 34

What is the ulna?

Answer 34

Ulna is the medial bone of the lower arm Proximal end of the ulna joins with the humerus to form the elbow joint Distally it also joins with the radius and some of the carpal bones of the wrist

Question 35

What bones make up the hand?

Answer 35

8 carpal bones make up the wrist 5 metacarpal bones make up the palm 14 phalanges- 3 for each finger and 2 per thumb

Question 36

What is the pelvic girdle and what does it consist of?

Answer 36

Consists of the coxal (hip) bones and the lower extremities

Question 37

What are coxal bones?

Answer 37

Coxal bones attach the legs to the axial skeleton and help protect the pelvic organs Three parts: the ilium (when you put your hands at the hip), the ischium (what you sit on ), and the pubis Two pubic bones form the front of the coxal bone and come together at the pubic symphysis = a fibrocartilagious joint. The joint become more lax when you give birth

Question 38

What is the femur?

Answer 38

Femur is the thigh bone , longest and heaviest in the body Proximal end joins with the hipbone at the hip socket or acetabulum. Distal end of the femur attaches to the tibia (shinbone) and the patella or kneecap

Question 39

What is the tibia and Fibula?

Answer 39

Tibia is the medial bone Proximal end joins with the femur and fibula. Distal end attaches to the ankle bones. Fibula is the thinner, lateral bone

Question 40

What are joints and what are they classified as?

Answer 40

Junctions or articulations between bones | Based on their structure, joints can be classified as fibrous, cartilaginous, or synovial

Question 41

What are fibrous joints?

Answer 41

Connected together with short connective tissue fibers abundant with collagen that do not allow much, if any, movement Examples Between cranial bones (called sutures) and facial bones

Question 42

What are cartilaginous joints?

Answer 42

Connected together by a disc of cartilage and are slightly movable Examples Between vertebrae

Question 43

What are Synovial joints?

Answer 43

``` Most numerous type and most movable Structure Covered with hyaline cartilage Surrounded by a fibrous joint capsule Lined with a synovial membrane which secretes a slippery fluid called synovial fluid, acts as a lubricant Examples Elbows, knees, shoulders, and knuckles ```

Question 44

What are Diagnosis of fractures ?

Answer 44

Based on the clinical presentation and confirmed by x-rays | Computerized tomography scans and magnetic resonance imagining are used to more clearly assess the damaged area

Question 45

What are the healing steps of a fracture?

Answer 45

1. Hematoma forms at the site of the fracture. 2. Fibrocartilaginous callus forms. 3. Bony callus forms. 4. Remodeling occurs when dead cells are removed and new bone cells are laid down.

Question 46

What is Osteoarthritis (OA)

Answer 46

"wear and tear" Affects the weight-bearing joints of the hips and knees Cartilage between the bones and the bones themselves begin to break down Occurs in elderly individuals due to the aging process Joint stiffness, aching, and pain Anti-inflammatory drugs, intra-articular steroid injections, transplanting harvested cartilage cells, surgical scraping of the joint, joint replacement

Question 47

What is Rheumatoid Arthritis (RA)

Answer 47

Chronic systemic disease Autoimmune component (everyone) Synovial membrane is destroyed causing edema and congestion. Scar tissue forms, bones atrophy, and visible deformities become apparent. Moderate to severe pain in the affected joints Anti-inflammatory drugs, heat or cold treatments, cortisone injections, immunosuppressive drugs, low-impact aerobic exercise and warm water exercises

Question 48

What is Gout (Gouty Arthritis )

Answer 48

Type of arthritis associated with high uric acid levels in the blood Crystalline deposits in the joints, kidneys, and various soft tissues Acute or chronic joint pain, commonly in the great toe Pain medications, anti- inflammatory drugs, and dietary modifications

Question 49

What is Bursitis?

Answer 49

Inflammation of a bursa, the fluid-filled sac that cushions tendons Elbow, knee, shoulder, and hip Overuse and trauma to joints Joint pain, swelling, and tenderness in the structures surrounding the joint Rest, pain medications, steroid injections, aspiration of excess fluid from the bursa, and antibiotics if caused by infection

Question 50

What is carpal tunnel?

Answer 50

Occurs when the median nerve in the wrist is excessively compressed by an inflamed tendon Overuse of the wrist Weakness, numbness, pain, or a tingling sensation in the hand, wrist, or elbow Wrist splints, pain medications, steroid injections, surgery to reduce the pressure on the affected nerves

Question 51

What is Kyphosis?

Answer 51

Abnormally exaggerated curvature of the spine -Adolescent kyphosis Growth retardation or improper development of the epiphyses as a result of rapid growth No symptoms may occur, may be mild pain, tiredness, or tenderness or stiffness of the thoracic spine. Exercise, a firm mattress, and a back brace -Adult kyphosis Degenerative disc disease Pain, back weakness, and fatigue Spinal fusion or grafting, Harrington rods may also be surgically inserted

Question 52

What is Lordosis?

Answer 52

Exaggerated inward (convex) curvature of the lumbar spine Obesity, tuberculosis of the spine, poor posture, pregnancy, osteoporosis, and continual wearing of high heels Mild to moderate pain Preventing or treating the underlying cause

Question 53

What is Scoliosis?

Answer 53

Abnormal, S-shaped lateral curvature of the thoracic or lumbar spine Develop prenatally when vertebrae do not fuse together or result from diseases that cause weakness of the muscles that hold vertebrae together Back pain Back braces, surgery to correct spinal curves, and physical therapy to strengthen the spine

Question 54

What is Osteogenesis Imperfecta?

Answer 54

Brittle-bone disease Decreased amounts of collagen in their bones Disorder is hereditary Fractures, blue sclera, dental problems, hearing loss, a triangular face, abnormal spinal curves, very small stature, a small chest or barrel shaped chest, loose joint, and small muscles List of treatments is extensive

Question 55

What is Osteoporosis?

Answer 55

Bones become more porous over time and a decrease in bone density is the result. Hormone deficiencies, a sedentary lifestyle, a lack of calcium and vitamin D in the diet, bone cancers, corticosteroid excess, smoking, excess alcohol consumption, and the use of steroids pain management medication

Question 56

What is Osteosarcoma?

Answer 56

Bone cancer that originates from osteoblasts Cause is unclear Pain and swelling of the soft tissue around affected bones Surgery, chemotherapy, and radiation therapy Amputation of the affected limb and fitting of prosthesis may be necessary to prevent metastasis

Question 57

What is Paget’s Disease?

Answer 57

Bones become enlarged, deformed and weak. May be caused by a childhood viral infection and may have some genetic basis Bone pain, deformed bones, and fractures Surgery to remodel bones, hip replacements, medications to prevent bone weakening, and physical therapy

Question 58

Types of tests

Answer 58

* Serum calcium levels * Serum phosphate levels * Serum alkaline phosphatase(ALP) * Bone marrow examination * Microbial analysis * Synovial fluid analysis