1. The human skeleton
Humans skeletal system is composed of bones, cartilage, ligaments, and tendons
the Skeleton is the name given to the collection of bones that holds our body up.
The skeletal system provides movement, protection, and shape
Endoskeleton: An internal skeleton (as opposed to an exoskeleton, or external skeleton, as in an arthropod)
Bone: Hard connective tissue
Cartilage: Flexible connective tissue
Ligament: Connective tissue that joins bone to bone
Tendon: Connective tissue that joins muscle to bone

2. What are the Five main functions of the human skeleton
Protect the vital organs as brain
2. Give us shape
3. Allow us to move because our muscles
are attached to our bones
4. Storage of nutrients such as calcium.
5. Formation of blood cells.
Overview of the main functions of the skeleton.

3. Human Bone Charts human skeleton, anterior view
Review skeletal system.

4. Human Bone Charts human skeleton, posterior view
Review skeletal system.

5. The Human Skeletal System: described in two parts
1)The axial skeleton is composed of the vertebral column, ribs, sternum and skull.
2) The appendicular skeleton is composed of the upper and lower limb bones, and the bones that girdle them to the axial skeleton (pelvic and shoulder girdles).
-the skull together with the mandible forms the skeleton of the head.
-the vertebral column consists of 33 vertebrae.7 cervical,12 thoracic,5 lumbar,5 sacral and 4 coccygeal. The bodies of the vertebrae articulate with each others by intervertebral discs.

6. The thoracic vertebrae having the ribs attached to them, together with sternum they form the skeleton of the thoracic cage.
The sacral vertebrae united to form a triangular bone called sacrum together with two hip bones form the skeleton of pelvis.
The same do the coccygeal vertebrae they unite to form the coccyx.
The skeleton of each limb, consist of three segments: proximal, intermediate and distal segment.
The shoulder girdle is formed by clavicle and scapula.
The pelvic girdle is formed by two hip bones.

7. The Human Skeletal System
1)Upper limb: The arm contains one bone called humerous.
The forearm…2 bones: medial is the ulna while the lateral bone is radius
The hand consists of carpal ,metacarpal and phalanges.
2)Lower limb: the thigh is formed by one bone called femur.
The leg: 2 bones tibia…medial.
The fibula …lateral.
The foot,,,, tarsal ,metatarsal and phalanges
Upper appendages: the arms, forearm and hands
Lower appendages: thighs legs, and feet

8. The Bony Thorax Made-up of three parts Sternum Ribs Thoracic vertebrae
Forms a cage to protect major organs

9. Bones of the Shoulder Girdle

10. Bones of the Upper Limb
The arm is formed by a single bone
Humerus

11. Bones of the Upper Limb
The forearm has two bones
Ulna
Radius

12. Bones of the Upper Limb The hand Carpals – wrist Metacarpals – palm
Phalanges – fingers

13. The Pelvis

14. Bones of the Lower Limbs
The thigh has one bone
Femur – thigh bone

15. Bones of the Lower Limbs
The leg has two bones
Tibia
Fibula

16. Bones of the Lower Limbs
The foot
Tarsus – ankle
Metatarsals – sole
Phalanges – toes

17. Types of Bones
Bone Types: Bones can be categorized by their shape into:1)long bones as femur and humerus.
2 ) short: carpal, tarsal.
3) Flat :scapula and bones of skull.
4) irregular: vertebrae.
-according to structure: compact ,cancellous.
-according to development: membranous, cartilagenous.
Parts of long bones:
-2 end (epiphysis) and a shaft (diaphysis).
-the epiphysis is separated from diaphysis by epiphyseal cartilage .it is covered by articular cartilage.
-the shaft contains a cavity called madullary cavity containing bone marrow. it is covered by a membrane called periostium.
Categorized by development:
Endochronal – from embryonic cartilage
Dermal – from embryonic connective tissue
Alveolar – from special cells found only in jaw bones
Sesamoid – within tendons
Wormian – within the flat bones of the skull
Categorized by shape:
Flat – thin, flattened, often slightly curved
Irregular – unique, often complicated shape that is not geometrically describable
Short – square-like shape
Long – elongated shape

18. Classification of Bones on the Basis of Shape

19. Gross Anatomy of a Long Bone
Diaphysis
-Shaft
-Composed of compact bone
Epiphysis
-Ends of the bone
Composed mostly of spongy bone
Articular cartilage
-Covers the external surface of the epiphyses
- Made of hyaline cartilage
-Decreases friction at joint surfaces

20. Structures of a Long Bone
Medullary cavity
Cavity of the shaft
Contains yellow marrow (mostly fat) in adults
Contains red marrow (for blood cell formation) in infants
Figure 5.2a
Slide 5.8b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

21. General features of bones
1)elevation………-tuberosity.
-tubercle condyle epicondyle.
-process spine line.
-crest.
2)depressions…….-fossa groove notch.
3)perforations…….-foramen canal.
-fissure.

22. JOINTS Joints are where two or more bones articulate (move).
Joints are classified according to how much movement they allow.
Fibrous – these are fixed or immovable joints such as sutures of skull. inf. tibiofibular joint (syndesmosis) - teeth gomphosis.
Cartilaginous – either primary or secondary.
these are slightly movable joints .
Primary: hyaline cartilage ,ossify by time, as epiphyseal cartilage.
Secondary: fibrocartilage ,didnt ossify, as intervertebral disc and symphysis pubis.
3. Synovial – these are freely movable joints such as the shoulder and hip joints.

23. Types of Joints

24. Types of Joints

25. Synovial Joints Articulating bones are separated by a joint cavity.
Synovial fluid is found in the joint cavity.
Articular cartilage (hyaline cartilage) covers the ends of bones
Joint surfaces are enclosed by a fibrous articular capsule.
Have a joint cavity filled with synovial fluid.
Ligaments reinforce the joint (extracapsular or intracapsular)

26. Structures Associated with the Synovial Joint
Bursae – flattened fibrous sacs
Lined with synovial membranes
Filled with synovial fluid
Not actually part of the joint.
- inside the joint there may be:
1)Tendon and its sheath
Elongated bursa that wraps around a tendon.
2) A disc as in sternoclavicular joint.
3)A meniscus as in knee joint.
4)A labrum as in hip and shoulder joints.

27. The Synovial Joint Slide 5.51 Figure 5.28
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

28. Types of Joints

29. Features of a synovial joint
Synovial joint have a number of common features.
FEATURE
FUNCTION
Hyaline/ articular cartilage
Prevents friction between articulating bones
Two layered joint capsule
To strengthen joint
synovial membrane ,covering non articular parts of bons ,secrets Synovial fluid
Reduce friction
Nourish cartilage
To get rid of waste from joint

30. FEATURE
STRUCTURE
FUNCTION
Ligament
A band of strong fibrous connective material
Joins bone to bone
Provides stability
Pads of fat
Fatty pad found between capsule, bone or muscle
Increases joint stability
Acts as shock absorber
Reduces friction
Meniscus
A wedge of tough flexible cartilage .
As in knee joint.
Improves fit between bone ends
Increases stability
Reduces wear & tear to joint surfaces
Bursae
Fluid filled sac found between tendon and bone

31. Synovial joints types of synovial joint.
.a) uniaxial: movement around one axis
Hinge – elbow ,ankle joints (transverse axis).
2) Pivot – radio-ulna, atlas/axis. (longitudinal axis).
b) biaxial: 2 axes:
Condyloid (ellipsoid) – wrist, oval convexity is received in elliptical concavity
Saddle – carpometacarpal of thumb.( with slight rotation)
c) polyaxial: Ball & socket – hip and shoulder joints a rounded head is received in cup shaped cocavity.
- other types : plane synovial permits Gliding between carpal bones.

32. Types of Synovial Joints Based on Shape
Figure 5.29a–c
Slide 5.52a
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

33. Types of Synovial Joints Based on Shape
Figure 5.29d–f
Slide 5.52b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

34. JOINT POSSIBLE MOVEMENTS SHOULDER
Flexion & extension, adduction & abduction, circumduction, rotation
ELBOW
Flexion & extension
RADIO-ULNA
Pronation & supination
WRIST
Flexion & extension, adduction & abduction.
SPINE
Flexion & extension, lateral extension, rotation
HIP
Flexion & extension, adduction & abduction, circumduction, rotation.
KNEE
Flexion & extension , rotation
ANKLE
Dorsiflexion & plantaflexion

35. The pivot joint: The spine The wrist
gliding joints between the vertebral articular processes.
The wrist
In this joint the radius and ulna bones articulate with 2 of the carpal bones. (ellipsoid)
The pivot joint:
1) The radio-ulna
In this joint the radius and ulna articulate within the elbow joint.
This joint allows the elbow some twisting movement (pronation & supination.
2)Atlas/axis
In this joint the atlas and axis bones articulate to allow a rotation movement as in shaking your head.

36. The elbow joint
In the elbow the humerus articulates with the radius and the ulna.
Movement can only occur in one plane. (hinge)
The ankle joint
In the ankle the talus articulates with the tibia and fibula. (hinge)
Ligaments provide stability to the joint.

37. Hinge Joints The knee joint
In the knee joint the femur articulates with the tibia.
The patella (knee cap) helps to give a better angle of pull.
The fibula is not part of the knee joint and so the tibia is the weight bearing bone.

38. Ball & socket joints The hip joint
The head of the femur fits into a deep cavity called the acetabulum on the pelvic bone.
This deep cavity gives the hip joint stability.
The presence of strong ligaments add to the stability making it difficult to dislocate the hip.

39. The shoulder joint
The head of the humerus fits into a shallow cavity on the scapula called the glenoid fossa.
The shoulder is the most mobile joint in the body.
Stability is improved by ligaments and muscles.

40. Muscles It is the red flesh of our body.
It is attached to skeleton. So called skeletal muscles.
It is voluntary.
The flashy part called belly and two ends called attachments.
Attachments may be:
a) Directly through muscular tissue.
b) through fibrous tissue called tendon or apponeurosis.
Tendon means ribbon like rounded white fibrous tissue.
Apponeurosis means flattened expanded sheet like white fibrous tissue.
c) Combination of both.
-muscles are attached at both ends, the relatively fixed end called origin while the relatively movable end called insertion.

41. some muscles cross only one joint so act only on this joint called uniarticular.
Biarticular muscles multiarticular muscles.
Form of muscles : according to arrangement of muscle fibers.
1-parallel type………as sartorius.
2-muscles with short parallel fibers attached to a central axial tendon.
Called pennate type: they include 4 types
a) unipennate….muscle fibers attached to one side like half a feather
(flexor pollicis longus).
b) Bipennate as dorsal interossei.
c) multipennate: many bipennate structures together as deltoid.
d) circumpennate: muscle fibers attached to all sides of tendon.
3-fan shaped type : radial fibers converge from different directions to a terminal tendon.