1. Structure of the Skeleton
Chapter 7 Notes
Structure of the Skeleton

2. Cranium Mandible Clavicle Cervical vertebrae Scapula
Thoracic vertebrae
Sternum
Rib
Humerus
Lumbar vertebrae
Coxa/Pelvic girdle
Radius
Sacrum
Ulna
Coccyx
Carpals
Metacarpals
Phalanges
Femur
Patella
Tibia
Fibula
Calcaneus
Tarsals
Metatarsals
Phalanges

3. Structure of the Skeleton
Skeletal tissue forms bones.
Bones are organized or grouped to form major subdivisions.
Coordination of bones with joints and muscles allows for movement.

5. Subdivisions of the Skeleton
Axial - 80 bones
Skull - face and cranium
Earbones - 3
Hyoid bone - in neck,
not attached to any other bone
helps in tongue movement
Spinal column
Sternum and ribs –
thoracic cage

6. Hyoid Bone

7. Subdivisions of the Skeleton Continued
Appendicular skeleton bones
Upper extremities and Lower extremities
that connect to the:
Pectoral girdle - scapula and clavicle (shoulder)
and
Pelvic girdle - hips

8. Pectoral girdle
Pelvic girdle

10. Skull – 28 Bones - Major Subdivisions
Cranium - brain case – Made up of 8 bones:
Frontal - forehead and anterior top
Parietal (2) - give shape to top side of cranium
Temporal - lower sides of cranium

11. Skull - Major Subdivisions
Occipital - framework for lower, posterior skull
Sphenoid - helps form the base of the cranium
Ethmoid - irregular bone, posterior to nasal bones

12. Skull - Major Subdivisions Continued
Face
Maxilla
Mandible - lower jaw, only movable structure of face; strongest of face
Zygomatic arch -shapes cheeks
Nasal bones - shapes nose

13. Skull
Mastoiditis
Inflammation of the air spaces within the mastoid portion of the temporal bone.
Could spread to brain if left untreated.

17. Skull

19. Zygomatic
bone
Foramen magnum
Occipital bone
Occipital bone

20. Occipital
Lambioid suture
Sagittal suture
Coronal suture
Frontal

21. Vertebral Column – Spinal Column
Longitudinal axis of skeleton
Flexible due to segmentation
Backbone of body
head balanced on top
ribs suspended in front
lower extremities attached below
spinal cord enclosed within

22. Division of Column Cervical vertebrae - 7 Thoracic vertebrae - 12
Framework for the neck
1st = atlas
2nd = axis – for neck rotation
Thoracic vertebrae - 12
Allows for rib attachment
Lumbar
Support small of back
Sacrum and Coccyx
Fusion of vertebrae

23. Structure of a Single Vertebrae
Body - flat, round surface
Spinous process - lateral projections
Transverse process - lateral projections (winglike)
Vertebral foramen - hole for spinal cord
Curved - allows for strength and balance

24. Pathological Curvatures of the Spine
Lordosis
curve in lumbar region is exaggerated in concavity

25. Pathological Curvatures of the Spine
Scoliosis
any region is abnormally curved laterally

26. Pathological Curvatures of the Spine
Kyphosis
hunchback
convexity in thoracic region

28. Shoulder Girdle Clavicle Scapula
Forms one joint with trunk between 2 bones.
All shoulder movement involves this joint.

29. Pelvic Girdle
Stable, circular base, supports trunk and attaches lower extremities.
Three Parts
Ilium - largest and uppermost bone
Ischium - strongest and lowermost bone
Pubis - anteriormost bone
Strong ligaments attach sacrum to each hip bone.

30. Sternum Medial part of anterior chest wall. Xiphoid process Ribs
cartilaginous lower tip
Ribs
True Ribs – attached to sternum
False Ribs – their cartilages do not reach sternum directly
Floating – no attachment to sternum

31. Upper Limb
Humerus
Long bone that extends from the scapula to the elbow (when hit at distal end it is known as the funny bone).
Upper end has smooth rounded head that fits into cavity of scapula.
2 processes just below the head, greater and lesser tubercles .
Provide attachment for muscles.

32. Upper Limb Continued Radius Ulna
Located on the thumb side of the forearm.
Extends from the elbow to the wrist and crosses over ulna.
Ulna
Longer than the radius.
Overlaps the end of the humerus posteriorly.

33. Wrist and Hand Wrist - consists of 8 small bones - carpals
2 rows of 4 bones each
Hand - palm and 5 fingers
Palm - metacarpals – 5 - line up with each finger
Numbered 1 to 5 beginning with metacarpal of thumb.
Fingers – phalanges - 14 in each hand
3 in each finger
A proximal, a middle, and a distal phalanx
2 in the thumb – missing middle phalanx

34. Lower Limb Femur Patella Thigh bone
Longest bone in the body - extends from the hip to the knee.
Patella
Kneecap
Located in a tendon that passes anteriorly over the knee.

35. Lower Limb Continued Tibia Fibula
Largest and strongest bone of the lower leg.
Located medially and superficially.
Atriculates with the fibula and talus to form ankle joint.
Fibula
Smaller lower leg bone.
Located laterally and deep.

36. Foot Structure Tarsals (7) Arches allow for great support.
Big toe much more stable than thumb.
Tarsals (7)
Create ankle bones
Strong ligaments and leg muscle tendon keeps arches of foot.

37. Foot Continued Metatarsals (5) Phalanges Framework for soles of feet.
Articulate with phalanges.
Numbered 1 to 5 beginning on medial side.
Phalanges
Shorter than that of the fingers.
Align and articulate with metatarsals.
Each toe has 3 phalanges (same as hand).
Big toe has 2.

38. Skeletal Differences Males Females Larger and heavier
Pelvis is deep and funnel shaped
Pubic arch is narrow
Females
Pelvis is shallow, broad and flaring
Pelvic arch is wider

39. Age Changes in Skeleton
Incremental decrease in height that begins about age 30.
1/16 of an inch a year
Calcium levels fall
Bones become brittle and increasingly prone to fracture.
Osteoclasts outnumber Osteoblasts.

41. Frontal view:
Nasal bone
Maxilla
Mandible
Clavicle
Sternum
Rib (True)
Xyphoid process
Lumbar vertebrae
Ulna
Radius
Sacrum
Coccyx
Pelvic girdle (Coxa)

42. Femur
Patella
Tibia
Fibula
Metatarsals
Phalanx

43. Scapula
Humerus
Ulna
Radius
Carpals
Metacarpals
Phalanx/ Phalanges
Calcaneus
Ilium
Ischium