Skeletal System

Health Care Science

Technology

Copyright © The McGraw-Hill Companies, Inc.

Terms to know

• Abduction – motion away from the midline of the body

• Adduction- motion toward the midline of the body

• Flexion – decrease in the angle between two bones at their joint

• Extension – movement that straightens bones at their joint.

• Joint – point of juncture of two or more bones

• Ligaments – tissue which connects bones to bones at a joint

• Synovial fluid – lubricating fluids

• Tendon – tissue which connects muscles to bone

Skeletal System Terms• arthr/o………….joint

• burs/o…………bursa• carp/o………...carpels (wrist)

• chondr/o……cartilage• clavicul/o……clavicle (collar bone)

• coccyg/o………coccyx (tailbone)

• cost/o……………rib

• crani/o…………skull

• femor/o………femur (thigh bone)

• fibul/o…………fibula (thinner lower leg bone)

• humer/o …….humerus (upper arm bone)

• ili/o…………..ilium (part of the pelvis)

• ischi/o………….ischium (part of the pelvis)

• mandibul/o……mandible (lower jaw)

• maxill/o ………..maxilla (upper jaw)

• metacarp/o…….metacarpus (hand bones)

• metatars/o……..metatarsus (foot bones)

• muscul/o………muscle

• my/o…………...muscle

• myel/o…bone marrow

• oste/o…………bone• patell/o……….patella (knee cap)

• Phalang/o…phalanges (fingers and toes)

• pub/o………….pubis (part of the pelvis)

• radi/o………. radius (part of the forearm)

• sacr/o……….sacrum• scapul/o……..scapular (shoulder blade)

• spondyl/o…….vertebra• stern/o ……..sternum (breast bone)

• tars/o……….tarsals (ankle)

• ten/o………..tendon

• tendin/o………tendon

• tibi/o………….tibia (shin, larger lower leg bone)

• uln/o…………..ulna (part of the forearm)

• vertebr/o……..vertebra

The Skeletal System

• The adult body consists of 206 bones.

Functions of the Skeleton– Support

• Provides a framework for the body– Protection

• Protects vital organs– Movement– Storage areas

• Stores calcium– Production – produces blood cells in the

marrow

• Categories of Bones

long bones• Arms and legs (humerus, femur).

Long Bones

• The longest portion of a long bone is called the “shaft”. The outer portion is compact bone. Oxygen and nutrients are brought from the bloodstream to the compact bone.

• The shaft is also called the diaphysis. Each end of the shaft has an area shaped to connect to other bones by means of ligaments and muscles. These ends are called epiphysis

Short Bones

Are small, cube-shaped bones

• Examples: Wrists, ankles, and toes (carpals, tarsals).

Flat Bones

• Usually have large flat surfaces that cover organs. The shoulder blades, ribs, pelvis, and skull have flat bones

Irregular Bones

•Irregular bones are specialized bones with specific shapes.•The bones of the ears, face, and vertebrae are irregular bones.

Sesamoid Bones

– Sesamoid bones are formed in a tendon near joints.

• The knee cap (patella) is a sesamoid bone. Sesamoid bones are also found in the hands and

feet.

• Bone Marrow– Soft connective tissue is important in

the production of blood cells.– Red bone marrow is found in infants’

bones and in flat bones of adults.– Yellow bone marrow is found in most

other adult bones and is made up of connective tissue filled with fat.

Divisions of skeleton

• Axial Skeleton:– Skull

• Cranium• Face

– Vertebral column– Thorax

Bones of the Head (Skull)

– Frontal bone. – Ethmoid bone. – Parietal bone.– Temporal bone.– Occipital bone.– Sphenoid bone.

• The Spinal Column– Consists of 5 sets of vertebrae.

• Cervical vertebrae – 7 bones.

• Thoracic vertebrae – 12 bones.

• Lumbar vertebrae – 5 bones.

• Sacrum – 5 fused bones.

• Coccyx – the tailbone, formed from 4 fused bones.

The Vertebral Column

• Bones of the Chest– Clavicle, or

collarbone.– Sternum, or

breastbone.– Twelve pairs of

ribs.

• Bones of the Pelvis– Pelvic girdle –

large bone that forms the hips and supports the trunk of the body.

– Cartilage connects the 2 pubic bones.

– Upper extremities

– Arms • Humerus• Radius• Ulna• Carpals• Metacarpals• Phalanges

Appendicular Skeleton

Radius and Ulna

Bones of the Hand and Wrist

Appendicular Skeleton

– Lower extremities

– Legs • Femur• Patella• Tibia• Fibula• Tarsals• Metatarsals• Phalanges

The Femur

The Patella

Bones of the Foot

Joints

• Points where bones connect

• Connected with ligaments which are bands of fibrous tissue

Types of Joints

• Fixed Joints – allow no movement of bones (example: bones in the skull)

• Partially moveable joints – allow some movement of bones (example: vertebrae)

Moveable Joints

• Allows full movement of bones

• Different types of movable joints:– Ball-and-socket

joints allow movement in any direction.

Moveable Joints

• Hinge Joints – allow movement in only one direction

• Examples: elbow and knee

Moveable Joints• Pivot Joints –

allows rotating movement from side to side

Movable Joints

• Gliding joints

allows sliding movement back and forth (example: wrist)

Diseases and Disorders of the Skeletal System

• Fractures – breaks or cracks in the bone

Compound Fracture

• Also known as an open fracture, is a break with an open wound

Compound fx of the ankle

Comminuted fx

• A break in which the bone is fragmented or shattered

Spiral fx

• This occurs when a bone is twisted apart.

Osteoporosis• Softening of the bones due to lack of

calcium and exercising

Osteomyelitis

• Caused by bacteria in bone tissue

Arthritis

• It is an inflammation of the joints causing pain, stiffness, aching, and limited range of motion. The three common types are osteoarthritis, rheumatoid arthritis, and gout.

Osteoarthritisis degeneration of the joints and

erosion of the joint cartilage

Rheumatoid Arthritis

• A systemic disease affecting the connective tissue.

Gout

• An accumulation of uric crystals in the joints. It usually affects the big toe.

Sprain

• An injury or trauma to the joints that tears the ligaments. Symptoms include swelling, tenderness, pain, and an inability to move the area.

Scoliosis

• Side-to-side (lateral) curvature of the spine

Kyphosisalso known as a humpback

• Rounding forward at the thoracic vertebrae

Lordosisalso known as a swayback

• An abnormal inward curvature of the lumbar spine

Bursitis

• Inflammation of the bursa

Herniated Disc

• Also called a slipped or ruptured disc

• One or more of the spinal discs bulges out from inside the bony part of the vertebrae