3 Skeletal System - Terminology

periosteum

A fibrous layer of connective tissue surrounding a bone, contains nerve endings and serves as a point of attachment

endosteum

A connective tissue that lines the cavity(inside) of long bones; plays a role in remodeling and repair.

lamellae

Concentric rings (layers) made up of groups of hollow tubes of bone matrix

compact bone

hard, dense bone tissue, usually found around the outer portion of bones

osteon

the basic structural (functional) unit of compact bone

central canal

the center of osteon that contains blood vessels and nerves

perforating canal

canal perpendicular to the central canal in bone. Links blood vessels in the central canal to the periosteum and marrow cavity.

spongy bone

Layer of bone tissue having many small spaces and/or found just inside the layer of compact bone and the epiphysis of long bones, made of trabeculae

trabeculae

the irregular latticework of thin bony beams in spongy bone tissue

osteocytes

living bone cells - mature bone cell

osteoblast

bone-forming cell

osteoclast

cell that breaks down bone

lacunae

small cavities in between the lamellae of compact bone that contain osteocytes

canaliculi

Hairlike canals that connect lacunae to each other and the central canal

red bone marrow

found in spongy bone; site of hematopoiesis

yellow bone marrow

fatty tissue found in the marrow cavity of most adult long bones

epiphyseal line

in adults; remnant of epiphyseal plate after bone growth stops

epiphysis

the end of a long bone

diaphysis

shaft of a long bone

chrondrocytes

cartilage cell (avascular)

articular cartilage

covers the surfaces of bones where the bones come together to form joints

marrow cavity

the hollow central cavity that extends the length of the diaphysis. It also contains the bone marrow.

ligament

connective tissue that connects bone to bone

tendon

connective tissue that connects muscle to bone

ossification

process of bone formation from another material

osteolysis

destruction of bone

short bones

bones of equal dimensions - tarsals and carpals

long bones

bones that are longer than wide - humerus

irregular bones

bones that don't fit regular categories - vertebrae

flat bones

bones like the skull (parietal & frontal) and scapula

epiphyseal plate

when primary and secondary ossification have not met, and the bone is still growing

hematopoiesis

process of making blood- function of red bone marrow

calcium phosphate

one of the salt compounds that make up most of the matrix of bones

osteogenesis

term that means bone production

chondr/o

a word element which means cartilage

remodeling

term for the dynamic nature of bone where the matrix and salts are continually dissolved and replaced

scurvy

disorder where osteoblasts are affected due to low vitamin C levels

rickets

disorder where low vitamin D levels reduce Calcium absorption in intestines. Causes weak or bowed bones.

osteoporosis

abnormal loss of bony tissue resulting in fragile porous bones attributable to a lack of calcium, occurs more in women

female pelvis

pelvis where pubic angle is > 100 degrees and enlarged pelvic outlet/inlet

male pelvis

pelvis where pubic angle is < 100 degrees and the ilia project upwards/more vertical

open fracture (compound)

broken bone penetrates through the skin

closed fracture (simple)

a bone break that does not penetrate the skin

fracture

to break (a bone)

oste/o

a word element meaning bone

sesamoid bones

typically short bones formed in muscles and tendons near joint surfaces

osteoid

collagen fibers and calcium phosphate, the matrix of bone