Skeletal

Appendicular skeleton - Bones making up the limbs, pelvis, and shoulder areas

Axial skeleton - The skeleton that forms the central supporting axis of the body

Articulation - The site of close approximation of two or more bones

Articular cartilage - Thin layer of hyaline cartilage covering the surface of the epiphysis

Carpal bones - Small bones of the wrist

Condyle - Rounded knob; usually fits into a fossa on another bone to form a joint

Epicondyle - A bump superior to a condyle

Crest - A moderately raised ridge

Diaphysis - The central body/shaft-like portion of a long bone

Epiphysis - The head of each end of a long bone

Medullary cavity - The central hollow portion of a long bone that contains bone marrow

Endosteum - Thinner Inner lining/ Thin epithelial membrane lining the inside of the medullary cavity

Periosteum - Outer layer that covers the bone/ Dense fibrous membrane covering the diaphysis

Epiphyseal plate - Layer of cartilage separating the epiphysis from the diaphysis at each end of a long bone It is the site where bone growth occurs

False pelvis - Portion of the pelvis that extends between the edges of the iliac bones

Fontanel - Un-fused area of an infant’s skull

Fossa - A furrow or depression

Foramen - A round opening in a bone, usually a passageway for vessels and nerves

Okie Head - The prominent, expanded end of a bone

Haversian canal - A central canal in compact bone containing blood vessels and nerves; surrounded by lamellae

Intramembranous ossification - Process in the fetus whereby fibrous connective tissue evolves into bone

Endochondral ossification - bone forms within and replaces cartilage. Intramembranous ossification is the simpler of these two processes.

Kyphosis - An exaggerated thoracic curvature

Lacunae - Tiny gaps between rings of lamellae in compact bone

Lamellae - Concentric rings of matrix surrounding Haversian canal in compact bone

Meatus - A tube-like opening / also known as Canal

Osseous tissue - Bone tissue

Ossification - The creation of new bone / Bone Formation

Osteoblast - Bone-forming cell

Osteoclasts - Bone cells that dissolve old or unhealthy bone

Osteocyte - Mature osteoblast

Osteon - Basic structural unit of compact bone consisting of a Haversian canal and surrounding lamellae

Canaliculi - extracellular matrix of the lemellae within tiny canals

Process - A projection or raised area

Bone / Remodeling - Reshaping or reconstructing part of a bone

Resorption - The destruction of old bone; part of the bone remodeling process

Scoliosis - A lateral curvature of the spine

Sinus - Cavity in the skull filled with air

Spongy bone - Also called cancellous bone. It is found in the ends of long bones and the middle of most other bones

Sulcus - Groove or elongated depression

Sutures - Immovable joints of the skull

Trabecula - Latticework of osseous tissue that makes up the structure of spongy or cancellous bone

Trochanter - A large process. It is found only on the femur

True pelvis - Portion of the pelvis that extends between the pelvic brim Tubercle - A small, rounded process

Tuberosity - A rough, raised bump, usually for muscle attachment

Extracellular matrix - contains substances that are essential for the make-up of our bones since the cartilages, tendons, ligaments, and even our bones, are connective tissues.

Collagen - as one of the substances, is a tough and rope-like protein giving our tendons, ligaments and cartilages great amount of strength

hydroxyapatite - minerals in bone is in the form of calcium phosphate crystals

Proteoglycans - on the other hand, are large molecules consisting of polysaccharides

Classification of Bones

  1. Long Bones - longer than they are wide. Example: arms, legs, fingers, and toes

  2. Short Bones - are equal in length and width making then nearly cube-like shaped. Example: ankles and wrists

  3. Flat Bones - are thin and provide both protection and surfaces for muscle attachments. Examples: bones of the skull, sternum, and ribs.

  4. Irregular bones - Have complex shapes. Example: Vertebral Column

Functions of Skeletal System

  1. Support - It supports and stabilizes surrounding tissues such as muscles, blood and lymphatic vessels, nerves, fat, and skin.

  2. Protection - It protects vital organs of the body such as the brain, spinal cord, the heart, and lungs, and it protects other soft tissues of the body.

  3. Movement - It assists in body movement by providing attachments for muscles that pull on the bones that act as levers.

  4. Blood cell production - It manufactures blood cells.

  5. Storage - It is a storage area for mineral salts, especially phosphorus and calcium, and fats.

Two Types of Bones Tissue

  1. Compact/ Dense Bone - is strong and dense, provides protection and support, and resists the stresses produced by weight and movement.

  2. Cancellous/ spongy bone - lightweight, contains irregular lattices of thin bone columns called trabeculae.

Parathyroid hormone (PTH) - stimulates osteoclasts

Calcitonin - stimulates formation of osteoblasts.

Human growth hormone (hGH) and Insulin- like growth factor (IGF) - stimulates cartilage and bone growth

Sex hormones - also influence sex-related differences in skeletal growth.

Calcium, magnesium, and phosphorus - are minerals that contribute to our osseous tissues

Vitamins A, C, and D - vitamins that contribute to our osseous tissues

Broken bone protrudes through the skin, it is an open fracture.

If it broken bone protrudes within the skin, it is a closed fracture.

A hole in a bone is called a foramen.

If the hole is elongated into a tunnel-like passage through the bone, it is called a canal or a meatus.

A depression in a bone is called a fossa.

A lump on a bone is called a tubercle or a tuberosity, and a projection from a bone is called a process.

The smooth, rounded end of a bone, where it forms a joint with another bone, is called a condyle.

Body, Shaft - Main Portion

Head - Enlarged end

Neck - Constricted area between head and body

Condyle - smooth, rounded, articular surface

Facet - Small, flattened, articular surface

Process - Prominent projection

Tubercle - lump on a bone

Trochanter - Large tuberosity found only on proximal femur

Fissure - Cleft

Sinus - Cavity

The axial skeleton consists of 80 bones, while the appendicular skeleton consists of 126 bones.

The skull, which consists of 22 bones, rests on top of the vertebral column. It has two groups of bones: 8 cranial bones and 14 facial bones.

Frontal bone forms the forehead, roofs of the eye sockets, and front part of the cranial floor.

• The parietal bones (2) form the sides and roof of the cranium

• The temporal bones (2) form the lower side of the cranium and part of the cranial floor.

Nasal bones (2) form the bridge of the nose.

Maxillae (2) form the upper jawbone and join with all the other facial bones except the mandible also known as lower jawbone

The carotid artery passes through a foramen called the carotid foramen.

The styloid process serves as a point of attachment for the tongue and neck muscles.

Zygomatic bones (2), or cheekbones, form the cheek prominences and part of thewall of the eye sockets.

Lacrimal bones (2) are the smallest, thinnest bones on the medial eye socket.

Inferior nasal conchae (2) project into the nasal cavity to filter air before it passes toward the trachea and lungs.

The vomer joins with the maxillae and the palatine bones to form the floor of the nasal cavity.

Types of suture

  1. Coronal suture unites the frontal bone and two parietal bones.

  2. Sagittal suture attaches the two parietal bones.

  3. Lambdoid suture joins the parietal bones to the occipital bone.

  4. Squamous sutures seal the parietal bones to the temporal bones.

Paranasal sinuses are found in the sphenoid, frontal, ethmoid, and maxillary bones.

Mandible - largest and strongest facial bone, and the only one that moves

Fontanels are mesenchyme-filled spaces between the cranial bones of infants at birth.

hyoid bone is located in the neck, between the mandible and larynx.

Vertebral column - also called the spine, spinal column, or backbone protects the spinal cord, supports the head and neck, permits movement, and provides attachment points for the back muscles, ribs, and pelvis.

Vertebral column consists of 26 bones called vertebrae.

Cervical vertebrae (7) are in the neck region.

Thoracic vertebrae (12) are posterior to the chest cavity and serve as attachments for the ribs.

Lumbar vertebrae (5) form the lower back.

The sacrum consists of 5 fused vertebrae and forms the posterior wall of the pelvis.

The coccyx, sometimes referred to as the tailbone, consists of 4 fused vertebrae.

Vertebral Foramen - opening through which the spinal cord passes.

The vertebral arch extends posteriorly from the body. It consists of two short, thick processes called pedicles that project backward and join with two at parts called laminae.

Types of process

  1. Spinous process (1) projects from the laminae; it serves as attachment point for muscles.

  2. Transverse processes (2) are lateral extensions that serve as attachment points for muscles.

  3. Superior articular processes (2) attach to vertebra above.

  4. Inferior articular processes (2) attach to vertebra below.

Scoliosis—A lateral curvature that causes the spine to “lean” to one side more than the other. This condition is seen more commonly in females than in males.

Kyphosis—An exaggeration of the thoracic curve that forms a “humpback” appearance.

Lordosis—An exaggeration of the lumbar curve that causes a “sway back.”

Rib pairs 1 through 7 are called true ribs

Rib pairs 8 through 12 are called false ribs

Rib pairs 11 and 12 are referred to as floating ribs.

Bones in the upper body is the shoulder girdles or pectoral girdles.

Clavicle, or collarbone, attaches to the manubrium of the sternum and the scapula, or shoulder blade.

Coracoid process of the scapula serves as a point of attachment for muscles and its glenoid cavity forms the shoulder joint with the head of the humerus (upper arm bone).

Humerus - the longest bone in the upper body.

pelvic girdle is a basin-shaped ring of bones that connects the main part of the body (the chest, abdomen, pelvis and back) to the legs, it also consists of the two hip bones.

Attached to the sacrum of the vertebral column posteriorly and with each other anteriorly to form the pubic symphysis.

The bowl-shaped pelvis is formed by the coxal bones, sacrum, and coccyx.

The pelvic brim forms the boundary between the upper pelvis (false pelvis) and the lower pelvis (true pelvis). The false pelvis is part of the abdomen and contains the urinary bladder and the uterus. The true pelvis surrounds the pelvic cavity.

Blood vessels and nerves to the legs pass through openings in the lower pelvis called the obturator foramina.

Femur - (thigh bone), the longest single bone in the body.

The femur bends medially and attaches distally to the patella - (knee cap)

tibia is the large medial bone of the shin and bears most of the weight

lateral bone of the shin is called the fibula

The ankle bones, or tarsals, consist of 7 bones.

The talus is part of the ankle joint, while the calcaneus forms the heel of the foot.

The metatarsals (5) are like the metacarpals of the hand.