1. CHAPTER 3 The Skeletal System

2. Structures and Functions  Consists of bones, bone marrow, cartilage, joints, ligaments, synovial membrane (and fluid), and bursa  Bones act as the body’s framework  They support and protect the internal organs  They work with muscle, ligament and tendon to create movement  Calcium is stored in bone  Red bone marrow creates blood cells

3. Bone Parts

4. Bone Marrow  Red bone marrow is located in the spongy bone  It is hemopoietic – (hem/o = blood, poietic = pertaining to formation)  Red blood cells are formed in the spongy bone

5. Cartilage  Blue/white connective tissue that acts as a shock absorber between bone  Articular cartilage covers the surface of bones where they form joints  The meniscus is the curved cartilage found in some joints

6. Cartilage

7. Anatomic Landmarks of Bones  Diaphysis – long shaft of the bone  Epiphysis – the wide end of a long bone  Foramen – an opening in the bone where blood vessels, nerves, and ligaments may pass  Process – a normal projection on the surface of a bone where muscles and tendons may attach

8. Joints  Known as articulations  The place of union between two bones  Classified by their construction  Also classified by their degree of movement

9. Fibrous Joints  Known as sutures in adults  Do not allow any movement  Connective tissue hold them tightly together  They may be moveable in infants and small children to allow for growth  Fontanells (soft spots) on the head of an infant are an example of this type of joint

10. Fibrous Joints

11. Cartilaginous Joints  Allow slight movement  Consists of bones connected entirely by cartilage  Where the ribs connect to the sternum  The pubic symphysis (between the pubic bones)

12. Cartilaginous Joints

13. Synovial Joints  Where two bones articulate to permit a variety of movements  They include ball and socket and hinge joints  Synovial capsule - the sleeve that surrounds the joint  Synovial membrane – lines the capsule and secretes fluid  Synovial fluid – flows within the cavity and acts as a lubricant for smooth movement

14. Synovial Joints  Ligaments – connect bone to bone  Bursa – sacs or “pillows” that cushion and ease movement

15. THE SKELETON Axial Skeleton (green) Protects the major organs. 80 bones, including the skull. Ribs, sternum, and vertebrae Are also included.

16. THE SKELETON Appendicular Skeleton (red) Makes body movement possible. 126 bones; split into upper and lower extremities The “appendages”

17. BONES OF THE SKULL  The cranium  Crani means skull, um is a noun ending  Frontal bone forms the forehead  Parietal bones form the roof and upper sides  Occipital bone forms the posterior floor and walls  Temporal bones form the sides and base  Sphenoid bone forms parts of the base, floor and sides of the orbit  Ethmoid bone forms part of the posterior of the nose, the orbit, and the floor of the cranium

18. BONES OF THE SKULL

20.  Bones of the Face  Nasal bones – nose bones  Zygomatic bones – cheek bones  Maxillary bones – upper jaw  Palatine bones – roof of the mouth; “palate”  Mandible – jaw bone

21. BONES OF THE SKULL

22. Thoracic Cavity  Known as the rib cage  Ribs – called costals; 12 pair First 7 are true ribs Next 3 are false ribs Last 2 are floating ribs  Sternum – known as the breastbone Manubrium is the top part The body of the sternum forms the middle Xiphoid process is cartilage that forms the lower tip

23. Thoracic Cavity

24. The Shoulder  The structure that supports the arms  Clavicle – also known as the collar bone  Scapula – the shoulder blade  Acromion – the high point of the scapula where the clavicle attaches

25. The Shoulder

27. The Arm  Humerus – the bone of the upper arm  Radius – the smaller, shorter bone of the forearm on the thumb side  Unla – the longer forearm bone that joins the humerus to form the elbow joint

28. The Arm

29. Wrists, hands and fingers  Carpals – the 8 small bone that make up the wrist  Metacarpals – the 5 bones that form the palm and hand  Phalanges – the 14 bones of the fingers

30. Wrists, hands and fingers

31. The Spinal Column  Known as the vertebral column  Supports the head and body  Consists of 26 vertebrae (a single segment of the spinal column)

32. The Spinal Column

33.  Vertebrae –  5 sections – Cervical, thoracic, lumbar, sacral, and coxyx  Has a body, a foramen, a lamina, a transverse process, and a spinous process

34. The Spinal Column

35.  Cervical vertebrae  form the neck  7 vertebrae  Thoracic vertebrae  Make up the torso  12 vertebrae  Lumbar – 5 vertebrae of the low back  Sacrum and Coccyx make up the connection to the pelvis

36. The Pelvic Girdle  Consists of the pelvis and hips  Illium – broad blade shaped bone that forms the back and sides of the hips  Ischium – forms the lower posterior portion of the pubic bone  The pubis forms the anterior portion of the pubic bone  The sacroiliac joint is slightly moveable and is the connection of the spine to the pelvis  The acetabulum is the hip “socket” where the leg joins the body

37. The Pelvic Girdle

38. Legs and Knees

39.  The femur is the upper leg bone  It articulates with the acetabulum  It is “L” shaped at the head, forming the femoral neck  The knee is the articulation of joints that join the upper and lower leg  Consists of a tibial-femoral joint and a patello-femoral joint  The patella is the knee cap  The knee contains cruciate and co-lateral ligaments, and a meniscus

40. Legs and Knees

41. The Lower leg  The tibia, also known as the shinbone, is the larger, weight bearing bone in the lower leg  The fibula is the smaller, lateral bone  The distal heads of the tibia and fibula make up the maleoli.

42. The Ankle  The ankle joins the foot with the lower leg  The tarsal bones, similar to the carpals of the wrist, are the talus and the calcaneus.  The talus articulates with the tibia and fibula to make the joint

43. Feet and Toes  The five metatarsals form the mid foot area  The phalanges of the foot attach to the metatarsals

44. Feet and Toes

45. Anterior skeleton

46. Posterior Skeleton