Anatomy and Physiology

1. Anatomy and Physiology The Skeletal System Chapter 7 Community Education Mr. Kestner

2. Skeletal System • Made of organs called bones • Dense material due to mineral deposits • Calcium phosphate • Adult human has 206 bones • Bones work as system to perform functions

3. Bone Functions • Framework • Support body’s muscles, fat, and skin • Protection • Surround vital organs to protect them • Examples include skull – brain, ribs – heart and lungs • Levers • Attach to muscles to provide movement • Production of blood cells • Help produce red and white blood cells and platelets – hematopoiesis • Storage • Store most of body’s supply of calcium and phosphorus

4. Histology of Bone • Dense (compact) Bone • Strong, dense, ossified • Spongy (cancellous) Bone • Many open spaces, spongy appearance • Bone marrow within spaces • Ossification • Intramembranous • Calcium deposits hardens within periosteum • Endochondral • Bone cells developed within cartilage

5. Classification of Bones by Shape • Long Bones • Length exceeds width • extremities • Short Bones • Lack long axis • Wrists/ankles • Flat Bones • Pelvis, shoulder, chest • Irregular Bones • Vertebrae, ossicles of ear • Sesamoid Bones • Enclosed in a tendon • kneecap

6. Long Bone Parts • Bones vary in shape and size depending on location • Bones of extremities called long bones • Basic parts of long bones • Diaphysis – shaft • Epiphysis – two extremities (ends) • Medullary canal – cavity in diaphysis • Endosteum – membrane lining inside of bones • Periosteum – membrane lining outside of bones • Osteoblasts – special cells that form new bone tissue

7. Medullary Canal • Filled with yellow marrow, mainly fat cells • Red marrow is found in certain bones such as the vertebrae, ribs, sternum, cranium, and in the proximal ends of the humerous and femur • Produces red blood cells (erythrocytes), platelets (thrombocytes), and some white blood cells (leukocytes) • Involved with body’s immune response • Used to diagnose blood diseases and is sometimes transplanted in people with immune disorders

8. Periosteum • Covers outside of bones • Contains blood vessels, lymph vessels, and osteoblasts • Necessary for bone growth, repair, and nutrition • Thin layer of articular cartilage covers the epiphysis and acts as a shock absorber when two bones meet to form a joint

9. Bone Markings • Processes – obvious bony prominences • Spine – sharp, slender (vertebrae) • Condyle – rounded, knuckle-like (femur) • Tubercle – small round process (humerus) • Trochlea – pulley-shaped process (humerus) • Trochanter – very large projection (femur) • Crest – narrow ridge of bone (ilium) • Line – less prominent ridge than crest ( • Head – terminal enlargement (humerus, femur) • Neck – connects head to rest of bone (femur) • Fossae – any depression or cavity in a bone • Suture – narrow junction found between two bones (cranium) • Froamen – opening for vessels, nerves, etc. (f. magnum-skull, obturator f.-pelvis) • Meatus or Canal – long, tube-like passage (auditory meatus or canal) • Sinus – cavity within a bone (nasal or frontal sinuses) • Sulcus – furrow or groove (intervertebral sulcus)

10. Skeletal Sections • Axial skeleton • Forms main trunk of body • Composed of skull, spinal column, ribs, and breastbone • Appendicular skeleton • Forms the extremities • Composed of shoulder girdle, arm bones, pelvic girdle, and leg bones

11. The Skull • Composed of cranial and facial bones • Cranium • At birth, cranium is not solid bone • Spaces called fontanels, or “soft spots,” allow for enlargement of skull as brain grows • Made of membrane and cartilage that turn into solid bone at approx. 18 mo. age • Sutures – areas where cranial bones joined together • Sinuses – air spaces in bones of skull that act as resonating chambers for the voice • Lined with mucous membranes • Foramen – openings in bones that allow nerves and blood vessels to enter and leave bone

12. The Skull • Cranium • Spherical structure surrounding brain • Made of 14 bones: • 1 frontal • 2 parietal • 2 temporal • 1 occipital • 1 ethmoid • 1 spenoid • 6 auditory ossicles (3 each ear)

13. The Skull • Facial bones – 16 • 2 nasal – nose • 2 palatine – hard palate • 2 maxillary – upper jaw • 2 zygomatic – cheek • 2 lacrimal – inner aspect of eyes • 2 turbinates (nasal conchae) • 1 vomer bone • 1 mandible – lower jaw

14. The Spinal Column • Made up of 26 bones called vertebrae • Protect spinal cord & provide support for head and trunk • Includes: • 7 cervical – neck • Atlas – supports head • Axis – acts as a pivot to rotate head • 12 thoracic – chest • 5 lumbar – waist • 1 sacrum – (5 fused bones) • 1 coccyx – tailbone • Pads of cartilage tissue, called intervertebral disks, separate vertebrae and act as shock absorber • Intervertebral disks also permit bending and twisting movements of the vertebral column

15. The Chest • Ribs (or costae) • 12 pair • Attach to thoracic vertebrae • First seven pairs are called true ribs – attach directly to sternum • Next five pairs called false ribs • First three pairs attach to cartilage of rib above • Last two pairs called floating ribs because they do not attach to front of body • Sternum – breastbone • Consists of three parts • Manubrium (upper region) • Gladiolus (body) • Xyphoid process (small piece of cartilage at bottom) • 2 clavicles (collarbones) attached to manubrium by ligaments • Ribs are attached to sternum with costal cartilages to form a “cage” to protect heart and lungs

16. Shoulder Girdle • Made of: • 2 clavicles – collarbone • 2 scapulae – provide for attachment of upper arm bones • Bones of each arm include: • 1 humerus – upper arm • 1 radius – lower arm, thumb side • 1 ulna – large bone of lower arm • projection at upper end called olecranon process (elbow) • 8 carpals – wrist • 5 metacarpals – palm of hand • 14 phalanges – fingers

17. Pelvic Girdle • Made of: • 2 ox coxae (coxal, or hip bones) • Join with sacrum on dorsal part of body • Ventral part of body joined at symphysis pubis • Each made of 3 fused sections: • Ilium • Ischium • Pubis • Contains 2 recessed areas (sockets) called acetabulae • Opening between the ischium and pubis, called obturator foramen, allows for passage of nerves and blood vessels to and from legs

18. Pelvic Girdle • Bones of each leg include: • 1 femur – thigh • 1 patella – kneecap • 1 tibia – shin bone • 1 fibula – smaller bone of lower leg • 7 tarsals – ankle • The heel is formed by the large tarsal bone called the calcaneous • 5 metatarsals – instep of foot • 14 phalanges – toes

19. The Skeletal System • Joints are areas where two or more bones join together • Connective tissue bands, called ligaments, help hold long bones together at joints • There are three main types of joints: • Diarthrosis: freely movable • Ball-and-socket like shoulder and hip • Hinge like elbow and knee • Amphiarthrosis: slightly movable • Attachment of ribs to thoracic vertebrae • Synarthrosis: immovable • Cranium

20. Diseases and Abnormal Conditions of the Skeletal System

21. Rickets • Caused by deficiencies in calcium and phosphorus or deficiency in Vitamin D • Vitamin D is necessary for Ca absorption • Causes changes in bone known as rickets • Bones fail to ossify resulting in weakness • Bones in children easy to break • Usually occurs in children who do not receive adequate supply of Vitamin D

22. Rickets

23. Fractures • A crack or break in a bone • Types of fractures: • Greenstick • Simple or closed • Compound or open • Impacted • Comminuted • Spiral • Depressed • Colles

24. Greenstick Fracture • Bone is bent and splits, causing a crack or incomplete break; common in children

25. Simple or Closed Fracture • Complete break of the bone with no damage to the skin

27. Compound or Open Fracture • Bone breaks and ruptures through the skin; creates an increased chance of infection

29. Impacted Fracture • Broken bone ends jam into each other

30. Comminuted Fracture • Bone fragments or splinters into more than two pieces

31. Spiral Fracture • Bone twists resulting in one or more breaks; common in skiing and skating accidents

32. Depressed Fracture • A broken piece of skull bone moves inward; common with severe head injuries

33. Colles Fracture • Breaking and dislocating of the distal radius that causes a characteristic bulge at the wrist; caused by falling on an outstretched hand

34. Fractures • Before a fracture can heal, the bone must be put back into its proper alignment; a process is called reduction • Closed reduction – positioning bone in correct alignment, usually with traction, and applying cast or splint to maintain position • Open reduction – involves surgical repair of bone; in some cases special pins, plates, or other devices are surgically implanted to maintain correct position of bone

36. Abnormal Curvatures of the Spine • Kyphosis • “Hunchback” – a rounded bowing of the back at the thoracic area • Scoliosis • A side-to-side, or lateral, curvature of the spine • Lordosis • “Swayback” – an abnormal inward curvature of the lumbar region

37. Abnormal Curvatures of the Spine • Poor posture, congenital (at birth) defects, structural defects of the vertebrae, malnutrition, and degeneration of the vertebrae can all be causes of these defects • Therapeutic exercises, firm mattresses, and/or braces are the main forms of treatment • Severe deformities may require surgery

38. Kyphosis Scoliosis Lordosis

39. Osteoporosis • Increased porosity or softening of bones • A metabolic disorder caused by a hormone deficiency (esp. estrogen in ♀), prolonged lack of ca++ in the diet, and a sedentary lifestyle • The loss of calcium and phosphate from the bones causes bones to become porous, brittle, and prone to fracture

40. Osteoporosis • Bone density tests lead to early detection and preventive treatment • Treatment • Increased calcium and vitamin D intake • Medications to increase bone mass • Exercise • Estrogen replacement

41. Ruptured or Herniated Disk(sometimes called slipped disk) • Intervertebral disk ruptures or protrudes causing pressure on the spinal nerve • Most common site is lumbar-sacral area, but can occur anywhere • Symptoms • Severe pain, muscle spasm, impaired movement, and/or numbness • Treatment • Pain, anti-inflammatory and muscle relaxant medications initially • Other treatments include rest, traction, physical therapy, massage therapy, chiropractic treatment, and/or heat or cold applications • A laminectomy (surgical removal of protruding disk) may be necessary for severe cases that do not respond to therapy

43. Cleft Palate and Cleft Lip • Cleft Palate – more common in females • Occurs when palatine processes of the maxillary bones do not fuse properly • Results in opening btw nasal & oral cavities • Difficulty in speaking, eating and drinking • Surgical repair to correct it • Cleft Lip – more common in males • Maxillary bones do not form properly • Surgical repair to correct it

44. Cleft Palate and Cleft Lip

45. Dislocation • A bone is forcibly displaced from a joint • Frequently occurs in shoulders, fingers, knees, and hips • After dislocation is reduced, dislocation is immobilized with a splint, a cast, or traction

47. Arthritis • Inflammation of the joints • Two main types: • Osteoarthritis – (most common form) a chronic disease that usually occurs as a result of aging, frequently affects the hip and knee • Rheumatoid arthritis – a chronic inflammatory disease affecting the connective tissues and joints

48. Arthritis

49. Osteoarthritis • Symptoms • Joint pain, stiffness, aching, and limited range of motion • Treatment • Although no cure, rest; applications of heat and cold; aspirin and anti-inflammatory medications, injection of steroids into joints, and special exercises are used to relieve symptoms

50. Rheumatoid Arthritis • Three times more common in ♀ than ♂ • Onset often occurs between age 35-45 • Progressive attacks can cause scar tissue formation and atrophy of bone and muscle tissue, which result in permanent deformity and immobility • Early treatment is important to reduce pain and limit damage to joints • Treatment is same as osteoarthritis and may include arthroplasty to replace damaged joint