1. Musculoskeletal System
Module 4

2. Skeletal system Part 1 of 2
The skeletal system is the internal framework of the body.
Skeletal system

3. Skeletal System at a Glance
Functions of Skeletal System
Internal framework of body
Supports body
Protects internal organs
Point of attachment for muscles
Produces blood cells
Stores minerals
Organs of Skeletal System
Bones of the skeleton
Joints
The skeleton supports the body; protects internal organs; serves as a point of attachment for skeletal muscles for body movement; produces blood cells and stores minerals.
The primary structures of the skeletal systems are bones and joints.

5. Anatomy and Physiology
Bones are body organs with blood supply, nerves, and lymphatic vessels
Bones are connected to each other to form skeleton
Framework for the body
206 bones
Each bone in the human body is a unique organ that carries its own blood supply, nerves, and lymphatic vessels.

6. Anatomy and Physiology
Red bone marrow within bones produces blood cells
Bones also:
Protect vital organs
Store minerals
Joint
Place where two bones meet
Held together by ligaments
Gives flexibility to skeleton
Bone marrow is the site of blood cell production.
A ligament holds together the joint where 2 bones meet.

7. Bones Also called osseous tissue One of hardest materials in body
Formed from gradual process before birth called ossification
Fetal skeleton is formed from a cartilage model
Flexible tissue is gradually replaced by osteoblasts (immature bone cells)
In adult bones osteoblasts mature into osteocytes
Formation of strong bones depends on adequate supply of minerals
Ossification is the gradual process of bone formation, beginning before birth.
Osteoblasts are immature bone cells.

8. Four Shapes of Bones Long bones Short bones Flat bones Irregular bones
Longer than wide
Example:
femur
humerus
Roughly as long as wide
carpals
tarsals
Plate- shaped
sternum
scapula
pelvis
Shape very irregular
vertebrae

9. Classification of bones by shape.

10. Long Bones Majority of bones in body Divided into: Diaphysis Epiphysis
The majority of all the bones in a human body are long bones.
Long bones are divided into the DIAPHYSIS and EPIPHYSIS

11. Diaphysis Central shaft Medullary cavity Open canal within diaphysis
Contains yellow bone marrow
Mostly fat
The center of the diaphysis contains an open canal- the medullary cavity.
*early in life this cavity also contains RED BONE MARROW, but as we age the Red marrow in the medullary cavity gradually convert to YELLOW BONE MARROW.

12. Epiphysis Wide ends of long bone Articular cartilage Covers epiphysis
Distal epiphysis
Proximal epiphysis
Articular cartilage
Covers epiphysis
Prevents bone rubbing on bone
The widened out ends of long bones is called the EPIPHYSYS.
The distal epiphysis is at the end of the bone furthest from point of attachment.
The proximal epiphysis is end of bone closest to point of attachment.

13. Periosteum Covers surface of bone not covered by articular cartilage
Thin connective tissue membrane
Contains numerous nerve and lymphatic vessels

14. Compact Bone Also called cortical bone Very dense and hard
Outer layer of bone
Found in both epiphysis and diaphysis

15. Cancellous Bone Also called spongy bone Found inside bone
Has spaces containing red bone marrow
Manufactures blood cells
CAN sell us or spongy bone is found inside the bone. Spongy bone has spaces in it, giving it a sponge like appearance. These spaces contain RED BONE MARROW which manufacture most of the body's blood cells.

16. Components of a long bone.

17. Bony Processes Projection from the surface of a bone
Rough processes provide place for muscle attachment
Smooth rounded processes articulate with another bone in a joint
Named for shape and location

18. Common Bony Processes Head Large smooth ball-shaped end of a long bone
Condyle
Smooth rounded portion at end of bone
Epicondyle
Projection above or on a condyle
Trochanter
Large rough process
Tubercle
Small rough process
Tuberosity
Read table

19. Bony Depressions Sinus Foramen Fossa Fissure Hollow cavity within bone
Smooth opening for nerves and blood vessels
Fossa
Shallow cavity or depression within a bone
Fissure
Deep groove or slit-like opening
Read table

20. The Skeleton Skeleton has two divisions Axial skeleton
Appendicular skeleton
The skeleton is divided into 2 sections the AXIAL and the APPENDICULAR skeletons.

21. Axial Skeleton Includes bones in: Head Neck Spine Chest Trunk
The bones of the axial skeleton for the central axis foe the whole body and protects many internal organs like the heart, lungs and brain.

22. The Skull Is divided into two parts
Cranium
Facial bones
Protects brain, eyes, ears, nasal cavity, and oral cavity
Attachment for muscles of chewing and turning the head
The skull protects the brain, eyes, ears, nasal cavity and oral cavity.
The skull is the point of attachment for the muscles of chewing and turning the head.

23. Bones of the Skull
Cranium- 1 frontal bone; 2 parietal bones; 2 temporal bones; 1 ethmoid bone; 1 sphenoid bone; 1 occipital bone
Facial- 1 mandible bone; 1 maxilla bone; 2 zygomatic bones; 1 vomer bone; 1 palatine bone; 2 nasal bones; lacrimal bones
Read bone names

25. Hyoid Bone Single U-shaped bone In neck between mandible and larynx
Attachment point for swallowing and speech muscles

26. The Trunk
Vertebral column
Sternum
Rib cage

27. The Vertebral Column Divided into five sections
Cervical - 7 vertebrae of neck
Thoracic - 12 vertebrae of chest
Lumbar - 5 vertebrae of low back
Sacrum - 5 fused vertebrae at base of spine
Coccyx - 3–5 small vertebrae attached to sacrum
Read table

29. The Rib Cage 12 pairs of ribs Attached to vertebral column at back
Provides support for organs, such as heart and lungs
True ribs
10 pairs attached to sternum in front
Floating ribs
Inferior 2 pairs
No attachment in front
All ribs attach to the vertebral column, but only 10 of the 12 pair attach in front to the sternum.

31. Appendicular Skeleton
Includes bones of:
Pectoral girdle
Upper extremities
Pelvic girdle
Lower extremities
The APPENDICULAR skeleton is responsible for movement. These are the bones for our lower extremities and muscles to attach to.

32. Upper Extremities Arm Each Arm Consists of: Humerus – upper arm
Ulna – part of forearm
Radius – part of forearm
Carpals – wrist bones
Metacarpals – hand bones
Phalanges – finger bones
Read list

33. Pelvic Girdle Also called os coxae, innominate bone, or hipbone
Attaches lower extremity to axial skeleton
Articulates with sacrum posteriorly
Consists of:
Ilium
Ischium
Pubis
The PELVIC GIRDLE consists of the ilium, ischium, and pubis.
The Pelvic girdle attaches the legs to the axial skeleton.

34. Lower Extremity Leg Consists of: Femur – thigh bone Patella – knee cap
Tibia – shin bone
Fibula – lower leg bone
Tarsals – ankle bones
Metatarsals – foot bones
Phalanges – toe bones
Read list

35. Joints Formed where two bones meet Also called an articulation
Three types based on movement allowed between the 2 bones:
Synovial
Cartilaginous
Fibrous
Synovial Joints-
Freely moving joints
Most common type of joint
Example is ball-and-socket joint
Bones held together by ligaments
Strong bands of connective tissue
Some contain a bursa
Sac-like structure lined with synovial membrane
Joints are formed when 2 bones meet, this is also called an ARTICULATION.
* Synovial joints are the most numerous in our bodies. Synovial joints are free moving.

36. Synovial Joints Enclosed in an elastic joint capsule
Contains synovial fluid
Lubricant secreted by synovial membrane
Ends of bones are covered with articular cartilage
The elastic joint capsule is lined with a SYNOVIAL MEMBRANE that secretes SYNOVIAL FLUID.

38. Cartilaginous Joints Allow slight movement
Hold bones firmly in place by solid piece of cartilage
Example
Pubic symphysis
An example of a CARTILAGINOUS JOINT is the pubic symphysis- where the left and right pubic bones meet in front of the lower abdomen. There are held in place by cartilage.

39. Fibrous Joints Allow almost no movement Joined by thick fibrous tissue
Example
Sutures of the skull
Fibrous joints allow for almost no movement since the ends of the bones are joined by a think fibrous tissue which may even fuse into solid bone.

40. Examples of three types of joints found in the body

42. ASK YOURSELF
…If you are practicing the terms introduced in chapter 4 in our text. ..If you are practicing the terms that will be on your pronunciation test.

43. REMEMBER
There will be a pronunciation test due at the end of week 7 (see the course calendar for due date) practice the terms.
Practice the use of the audio board in Blackboard, we will use to submit the pronunciation test- detailed directions on the syllabus.

44. CAUTION
This PowerPoint included only half of the information for this module.

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