Chapter III - Skeletal System

Skeletal System

Composed of 206 bones that make up the framework of the body.

350

The number of bones a newborn has…

Axial Skeleton

Composed of 80 bones that are medial to the trunk.

Appendicular Skeleton

Composed 126 bones that are separated from the trunk.

Water & Osseous Tissue

The 50/50 percentage that bones are composed of.

Trabecular Bone

Also known as the spongy bone, is a porous type bone tissue found at the end of long bones.

Cortical Bone

Also known as the compact bone, the dense outer layer of the bone that provides strength and rigidity to the skeleton.

Osteoblasts

Bone cells that form new bone tissue.

Osteocytes

Matured bone cells that mineralizes the bone.

Osteoclasts

Bone cells that break down and replace old bone tissue.

• Provide the framework of the body

• Protect internal organs

• Serve as a storage for minerals

• Plays a role in hematopoiesis

• Provide a place for muscle attachment

• Make movement possible through articulation
  

(6) Function of the Bone

Hematopoiesis

The formation of blood cells that takes place in the bone marrow.

Red Marrow

A type of marrow that produces the blood cells.

Yellow Marrow

A type of marrow that consists of fat cells.

Stem Cells

These cells are found inside the bone marrow and are hematopoietic bone cells.

Bone Marrow Transplant (BMT)

A treatment that replaces unhealthy marrow with a healthy one.

Long Bones

Short Bones

Flat Bones

Irregular Bones

(4) Classification of Bones by Shape

Humerus

The long bone located in the upper arm.

Tibia

The larger shin bone.

Fibula

The smaller shin bone.

Femur

The thigh bone; the longest and strongest bone in the body.

Radius

The larger forearm bone.

Ulna

The smaller forearm bone.

Short bones

These bones include the carpals of the wrist and tarsals of the ankle.

Flat bones

These bones include the skull, breastbone, and scapula.

Frontal Bone

Metopic Suture

Anterior Fontanelle

Coronal Suture

Sagittal Suture

Parietal Bones

Lambdoid Suture

Posterior Fontanelle

Occipital Bone

(9) Parts of the Skull

Diamond-Shaped

The shape of the anterior fontanelle.

Triangle-Shaped

The shape of the posterior fontanelle.

12-18 months

The anterior fontanelle closes in _________ months.

2-3 months

The posterior fontanelle closes in _________ months.

Epiphysis

The growing end of a bone

Epiphysis Plate

The plate that allows growth for the bone.

Diaphysis

The bone’s shaft.

Periosteum

Outside covering of the bone.

Medullary

Inner space containing bone marrow.

Endosteum

Lining of the medullary cavity.

Articular Cartilage

A covering at the end of the bones in moveable joints.

Cartilage

A dense connective tissue that consists of strong fibers embedded in a strong gel-like substance.

Hyaline Cartilage

Elastic Cartilage

Fibrocartilage

(3) Types of Cartilage

Ligaments

A fibrous connective tissue that connects two bones together.

Tendons

A fibrous connective tissue that connects the muscle to the bone

Joint

A place where two or more bones connect.

Synarthrosis

A joint that allows no movement.

Amphiarthrosis

A joint that allows slight movement.

Diarthrosis

A joint that allows free movement.

• Greater Trochanter

• Lesser Trochanter

(2) Prominent Bone Protrusions

Abduction

Adduction

Flexion

Extension

Supination

Pronation

Circumduction

Protraction

Retraction

Dorsiflexion

(10) Types of Body Movements at Diarthrotic Joints

Abduction

The movement of moving a body part away from the midline.

Adduction

The movement of moving a body part towards the midline.

Flexion

The movement of bending a limb.

Extension

The movement of straightening a flexed limb.

Supination

The movement of lying face upward.

Pronation

The movement of lying face downward.

Circumduction

The movement of moving a body part in a circular motion.

Protraction

The movement of moving a body part forward.

Retraction

The movement of moving a body part backwards.

Dorsiflexion

The movement of bending a body part backwards.

Vertebral Column

The ____________ comprises of 33 separate bones that are connected to form our spinal curves.

Vertabrae

The separate bones in our vertebral column.

• Cervical Curve

• Thoracic Curve

• Lumbar Curve

• Sacral Curve

(4) Spinal Curves

7 Vertebrae

The number of vertebrae in the cervical curve.

12 Vertebrae

The number of vertebrae in the thoracic curve.

5 Vertebrae

The number of vertebrae in the lumbar curve.

1 Vertebra

The number of vertebrae in the sacral curve.

Pelvis

The lower portion of the trunk of the body.

Male Pelvis (Android)

The ________ pelvis is shaped like a funnel and is heavier and stronger.

Female Pelvis (Gynecoid)

The _________ pelvis is oval to round and wider.

Gynecoid

Android

Platypelloid

Anthropoid

(4) Types of Pelvis

Platypelloid

The widest shape of pelvis.

Anthropoid

The narrowest shape of pelvis

Cephalopelvic Disproportion (CPD)

A pregnancy complication in which the baby’s head is proportionally too large or the mother’s pelvis is too small to easily allow the baby to fit through the pelvic opening.

Fracture

Breaks in the continuity of the bone.

• Complete

• Incomplete

(2) Types of Bone Fracture (Completeness)

Complete Fracture

A break in the bone where the bone is broken entirely into two or more pieces.

Incomplete Fracture

A break in the bone where the bone does not break all the way through.

• Open

• Closed

(2) Types of Bone Fracture (Penetration)

Open Fracture

When the broken bone penetrates through the skin.

Closed Fracture

When the broken bone does not penetrate the skin.

Transverse Fracture

A break pattern that is horizontal or perpendicular to the long axis of the bone.

Linear Fracture

A break pattern that is a straight line along the bone.

Greenstick Fracture

A break pattern where one side is fractured and the other remains intact.

Comminuted Fracture

A break pattern where the bone breaks into multiple pieces, specifically three or more.

Oblique Nondisplaced Fracture

A break pattern that is diagonal across the bone while maintaining its alignment.

Oblique Displaced Fracture

A break pattern that is diagonal across the bone that separates the alignment.

Spiral Fracture

A break pattern where a twisting force is applied to the bone causing a break.

Reduction & Immobilization

How are bone fractures treated?

• Hematoma Formation

• Callus Formation

• Callus Ossification

• Bone Remodeling

(4) Process of Bone Repair

Dislocation

The displacement of bones at the joint.

Sprain

The injury to a ligament caused by the tearing of fibers in the ligament.

Tendinitis

The inflammation of the tendon due to strain or overuse.

Osteoporosis

The age-related loss of bone mass or density.

Arthritis

The inflammation or swelling of one or more joints.

Rickets

The softening and weakening of bones in children due to extreme or prolonged vitamin D deficiency.

Osteomalacia

The rickets counterpart for adults.

Spina Bifida

The birth defect that involves the incomplete development of the spinal cord and its coverings.