Skeletal System

1. Skeletal System Objective: Understand / Remember the body’s system of support and Movement (1.02-1.03) How many bones are in the adult skeleton? Name 5 Bones by their correct name

2. Functions Of the Skeletal System

3. Functions of the skeletal system *Framework-supports body’s muscles, fat and skin *Protection-surrounds vital organs ex: Skull protects brain, Ribs protects heart and lungs *Levers-attach to muscles to help provide movement *Produce blood cells-red& white blood cells and platelets, a process called Hemopoiesis or Hematopoiesis *Storage-stores most calcium of body, in addition to phosphorous and fats

4. 1.Bone Formation Osteocytes- mature bone cells Osteoclasts- bone cells that deposit new bone (fracture) Embryo skeleton starts as collagenous protein fibers secreted by Osteoblasts (primitive embryonic cells) – later they change over to cartilage. At 8 weeks after conception, OSSIFICATIONbegins. Mineral matter begins to replace cartilage, creating bones. Infant bones are soft because ossification is not complete at birth. (example ?)

5. A small child’s bones are more flexible than a 30 year old’s. (Why?) What age are our bones completed growing? What happens if you break a bone? What happens as you get older? Name a bone condition that occurs most often in women.

6. Fontanels The “soft spots” on a baby’s head Why is this important in the birth process? Allows for enlargement of the skull as the brain grows Made of membrane and cartilage Turns into solid bone by about 18 months

7. II.Structure of Long Bones-found in extremities (arms and legs) • Diaphysis – long shaft • Epiphysis-ends • Medullary Cavity (canal) – center of the shaft, filled with yellow marrow, which is mostly fat cells, also cells that form white blood cells. What are these called?

8. Long bones continued • Endosteum – lines marrow cavity, keeps yellow marrow intact, produces some bone growth. • Periosteum – tough, out side covering of the bone- contains blood & lymph vessels and osteoblasts. Necessary for bone growth, repair & nutrition (Epiphyseal plate/wrist)Adolescents

9. Long Bones cont’d. • Articular cartilage- thin layer that covers the epiphysis, acts as a “shock absorber” when 2 bones meet to form a joint • Epiphyseal plate (growth plate)- • Soft and the“growing area” of tissue near the ends of long bones in children & adolescents; EXTREMELY vulnerable to injury. • Would the growth plate be calcified? Why?

10. Growth plate cont’d. • Would a growth plate fracture show up on an x-ray? • Why? • When would a “growth plate” close up? • Most growth plate fractures heal without any lasting effect. Whether an arrest (slowing) of growth occurs depends on the treatment provided, and the following factors, in descending order of importance:

11. *Severity of the injury.If the injury causes the blood supply to the epiphysis to be cut off, growth can be stunted. If the growth plate is shifted, shattered, or crushed, the growth plate may close prematurely, forming a bony bridge or “bar.” The risk of growth arrest is higher in this setting. An open injury in which the skin is broken carries the risk of infection, which could destroy the growth plate.

12. *Which growth plate is injured. Some growth plates, such as those in the region of the knee, are more involved in extensive bone growth than others. • *Type of fracture. Of the six fracture types described earlier, types IV, V, and VI are the most serious.

13. *Age of the child. In a younger child, the bones have a great deal of growing to do; therefore, growth arrest can be more serious, and closer surveillance is needed. It is also true, however, that younger bones have a greater ability to heal.

14. The most frequent complication of a growth plate fracture is premature arrest of bone growth. The affected bone grows less than it would have without the injury, and the resulting limb could be shorter than the opposite, uninjured limb. If only part of the growth plate is injured, growth may be lopsided and the limb may become crooked.

15. Growth plate injuries at the knee have the greatest risk of complications. Nerve and blood vessel damage occurs most frequently there. Injuries to the knee have a much higher incidence of premature growth arrest and crooked growth.

16. Compact and Spongy Bone • The shaft of the long bone is made of compact bone – ends are spongy bone. Ends of spongy bone contain red marrow where red blood cells are made. • What is the difference between compact and spongy bone? (Hint:blood cells)

17. Bone marrow is important in the manufacture of blood and is involved with the body’s immune response. • Used to diagnose blood diseases. • Used in transplants to people with defective immune systems • Example?

18. LET’S REVIEW • Mature bone cells are called ____________? • Leukocytes are produced in the ____, and it’s also called _____ bone? • Erythrocytes are produced in the _____ bone, or the ______? • Yellow marrow in located in the _____ _____? • # Bones in human body? • Acts as a “shock absorber” ____ ____ • Hardening of the bone is called __________ • “Soft spots” on a baby’s head are called _____________? • 5 functions of the skeletal system? • Framework/support, movement/levers, protection • Produce blood cells, storage • Inner/Outer coverings of the bone?

19. III. Structures of the Skeleton System Skeleton Divided into 2 parts: Axial Skeleton “Axis” ----------- forms main trunk of body. Composed of Skull, spinal column, ribs and sternum Appendicular Skeleton----------“Appendages”- forms extremities (arms & legs) Composed of shoulder girdle, arm bones, pelvic girdle, leg bones

20. Atlas (C1) • Cervical vertebrae #1 • Named after Greek god who “held the world on his shoulders” • Allows movement of head side to side and front to back • Axis (C2) • Cervical vertebrae #2 • Polelike structure which inserts into the atlas, allows head movement from side to side • Brain stem continues through axis to spine • “Sudden death” injuries –Why?

21. Types of Bones and Examples • Long Bones- • humerus • & femur • Short Bones- • carpals, • tarsals • phalanges • Flat Bones-skull • & ribs Irregular Bones- • spine

22. A. Axial Skeleton-(Skull,cranium,facial bones, spine, ribs/sternum) • Spherical structure that surrounds and protects the brain • Made up of 8 bones:------ • (Fontanels-previous slide) • Frontal-forehead • 2 Parietal-roof & sides • 2 Temporal-ear area • Ocipital-base of skull • Ethmoid-nasal septum • Sphenoid-“Connector” bone

23. Facial bones: • Nasal-bridge of nose • Vomer-lower part, over lip • Zygomatic Arch-cheek • Mandible-lower jaw • Maxilla-upper jaw • Hyoid-tongue/larynx • Palantine- hard palate, roof of mouth • Sutures- area where cranial bones join together • Sinuses- air spaces in bones of the skull, provide strength, resonates voice, lined with mucous membranes

24. Spinal (Vertebral) Column • Composed of 26 bones called vertebrae; Encloses the spinal cord/nerves • Provides support for head and trunk divided into 5 parts: • Cervicalvertebrae (7) in neck • Thoracicvertebrae (12) attaches to ribs • Lumbar vertebrae (5) waist area, low back • Sacrum (1) back of pelvic girdle • Coccyx (1) fused vertebrae called “tailbone”

25. Ribs (costae) • 12 pairs long slender bones • Attach to Thoracic vertebrae on dorsal surface • True Ribs- 1st 7 pair of ribs, attach directly to sternum on front of body • False Ribs- next 5 pairs of ribs, 1st 3 pair attach to cartilage above them • Floating Ribs- no attachment on front of body. Where do they attach?

26. Sternum- midline, mid chest • Breastbone- consists of 3 parts: • *Manubrium-upper part • *Gladiolus- center area • *Xiphoid process-small piece of cartilage @ bottom • (CPR) • 2 clavicles attach to the manubrium by ligaments • Ribs attach to sternum with costal cartilages to form a cage that protects the heart and lungs

27. Let’s Review for 9/12 • Axial skeleton consists of • Name the bones of the skull • The spinal column is divided into ___ parts • How many of each……. • Cervical vertebrae? • Thoracic? • Lumbar? • Sacrum? • Coccyx? • How many pairs of ribs • True ribs? • Sudden death would occur in which area? Why? • How are vertebrae identified? • Name 4 types of bones and give an example of each • Sinuses are _____ that allow air movement provide strength, resonates voice and are lined with mucous membranes. • Part of sternum, breaks during CPR?

28. B. Appendicular Skeleton “Appendages” Shoulder girdle Arms / Hands / Fingers Pelvic Girdle Legs / Feet / Toes 126 bones

29. Clavicle – collar bone Scapula – shoulder blade Humerus – upper arm Radius (thumb side) rotates around ulna Ulna (pinky side) (largest) – lower arm Carpals (8)– wrist bones held together by ligaments Metacarpals (5) – hand bones, forms palm Phalanges (14) on each hand- fingers Pelvis – 3 bones (ilium, ischium, and pubis) Femur – upper leg longest and strongest bone in the body Tibia-(largest) lower leg Fibula – lower leg Patella – knee cap Tarsal bones – ankle Calcaneus – heel bone Metatarsals – foot bones Phalanges - toes Appendicular Skelton

30. Joints Joints are points of contact between 2 bones. Synovial fluid is the lubricating substance in joints. (type of membrane?) Joints are classified according to movement. * Diarthrosis- freely movable; ballsocket/ hinge/pivot/gliding * Amphiarthrosis- slightly movable; ribs to spine/symphysis pubis (childbirth) * Synarthrosis- immovable joint (sutures)

31. Ball and Socket • The bone with a ball shaped head fits into a concave (dips in) socket of the 2nd bone. • Examples: shoulder and hip

32. Hinge joint • Move in one direction or plane. • Examples: knees elbows Outer joints of fingers

33. Pivot Joint • Those with an extension rotate on a 2nd, arch shaped bone. • Examples: • radius and ulna • atlas and axis

34. Gliding Joints Flat surfaces glide across each other. Vertebrae of the spine

35. Suture (Synarthrosis joint) An immovable joint connected by tough, fibrous connective tissue The bones of the skull, fused together to form a heavy protective cover for the brain

36. Types of Motion

37. Flexion and Extension • Flexion is decreasing the angle of the joint • Extension is increasing the angle of the joint

38. Abduction and Adduction • Abduction is taking it away from the body. • Adduction is bringing it toward the body.

39. Rotation and Circumduction • Rotation – the process of turning around on an axis • Circumduction – circular motion of a limb

40. Pronation (Prone) • To position on the anterior side. • Lay on your stomach • Palms are facing upward for hand position.

41. Supination (Supine) • To position on the posterior side • Lay on your back • Palms down for hand position

42. Disorders of Bones and Joints • Fractures • Dislocation • Sprain • Strain • Abnormal curvature of the spine • Arthritis • Osteoporosis

43. Fractures • Greenstick-bone is partially bent but never completely separates • Simple or closed – bone broken skin intact • Compound or open – bone broken and penetrates through the skin • Comminuted –bone breaks in many pieces/splinters, can embed in tissues • Which is most serious and why?

44. Fractures • Greenstick – bone is bent and splits causing an incomplete fracture. This is most common in children. • Why?

45. Treatment of Fractures • Closed reduction-position bone in alignment; traction w/cast or a splint. • Open reduction – is surgical intervention with devices such as wires, metal plates, or screws to hold the bone in alignment. • Traction – pulling force used to hold the bones in place – used for fractures of the long bones

46. Dislocation Bone is displaced from the proper position in the joint.

47. Sprain A sprain is a stretching or tearing of ligaments Sudden or unusual motion causes ligaments to be torn/damaged but joint not dislocated

48. Strain A strain is a stretching or tearing of muscle or tendon

49. Abnormal Curvatures of the Spine Scoliosis- Lateral curvature of the spine

50. Kyphosis “hunchback”, protrusion of the upper thoracic spine