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Bones  

Long bones  

• Found in limbs (legs, arms) 

• Serve as levers for movement  

• Greater length than width  

• Mostly compact bone  

• Examples: femur, humerus, ulna, radius, tibia, fibula 

Short bones  

• Very strong but have less movement (carpal and tarsal bones or foot) 

• Nearly equal in length and width. 

• Mostly spongy bone with an outer compact bone  

• Example: carpals, bones of the wrists and ankles  

Flat bones  

• Usually thin  

• 2 layers of compact bone covering a thin layer of spongy bone 

• Provide protection and a large area for muscle attachment 

Irregular bones  

• Mainly provide protection and support  

• Pubis vertebrae  

Sesamoid bones 

• Small bones developed in tendons around some joints  

• e.g. the patella (kneecap) 

The vertebral column 

• Each vertebrae have a hollow Centre through which the spinal cord travels 

• As the vertebrae descend from the cervical to the lumbar region they increase in size: this helps support the weight of the upper body  

• Number of vertebrae in each areaCervical:7 thorical:12 lumbar:5 sacrum:5 coccyx 4   

Joints  

Connective tissue  

• Connective tissue plays a large part in: 

• Stabling joints of the body 

• Act as lubricant and shock absorber between bones  

• Three main types of connective tissue are tendons ligaments and cartilage  

Cartilage  

• Cartilage is smooth, slightly elastic tissue 

• Some synovial joints also have cartilage between bones, e.g. the knee  

• The cartilage in the knee between the vertebrae provides shock Absorption during movements  

Tendons  

• Attach muscles to bones  

• Allow movement to take place, as they help muscles pull across the joints on the bones  

Ligaments 

• Cross over joints, joining bone to bone 

• Thair main function is to provide stability of the joint preventing dislocation 

• They cannot repair themselves if damaged or torn, and often surgery is necessary to repair them  

Joints  

• Joints are responsible for keeping bones far enough apart, so they do not rub against each other as they move, preventing damage  

• Joints are clasified by the amount and the type of movement they permit  

Three main types of joints  

1. Fixed (immovable) a fixed joint, one that allows no movement like the bones of our skull  

2. Cartilagenous (slightly moveable) joint that allows small restricted movement some of them are in-between our vertebrae  

3. Synovial joints (freely movable) allow movement in one or more direction's they are in our shoulder hip knee elbows 

Synovial joints  

1. Ball and socket joint allows circular movement in shoulder and hip 

2. Hinge joint permits a back and forth motion in our knees elbow and phalanges  

3. Pivot joining permits rotation of bone around another in our elbow  

4. Gliding joint permits a sliding motion of one bone over another found at ends of clavicle between writs and ankle bones  

5. Saddle joint permits movement in 2 directions  found at the base of the thumb  

6. Condyloid joint oval shaped head of bone in a shallow cavity allows movement in 2 planes in our wrist