SKELETAL SYSTEM TERMINOLOGIES

SKeletal system

This organ system provides a supporting framework for the body, a firm base to which the muscles of locomotion are attached, and protects the softer tissues enclosed within the framework.

Axial, appendicular, splanchnic

The skeleton can be considered to be made up of three parts:

Axial skeleton

This part of skeleton forms the central axis of the animal and comprising the skull, vertebral column and the ribcage.

Appendicular skeleton

This part of skeleton forms the front and hind limbs and the limb girdles which attach them to the body.

Splanchnic skeleton

This part of skeleton is found within the soft tissues.

319 to 321 bones

In total, how many bones are present in dogs?

Skull and hyoid = 50

Vertebral column = 50

Ribs and sternum = 34

Total = 134

What is the average number of the Axial Skeleton?

Thoracic limb = 90

Pelvic limb = 96

Total = 186

What is the average number of the Appendicular Skeleton?

Os penis = 1

Total = 1

What is the average number of the Splanchnic Bone?

Long Bone

This type of bone is proportionally longer than they are wide. Each has a central marrow cavity and a proximal and distal epiphysis. Examples include the femur and humerus.

Short bones

This type of bone is about as long as they are wide, and each has only one growth center. Examples are carpals and tarsals.

Flat bones

These types of bone have two plates of compact bone with spongy bone in between. This forms the trabeculae crossing from one side of the bone to the other.

Flat bones

These bones have no marrow cavity but have small, irregular marrow spaces. Examples include pelvic bones and skull bones.

diploë

The flat bones of the cranium consist of outer and inner tables of compact bone and an intermediate uniting spongy bone are called?

Irregular bones

All the irregularly shaped bones, such as the vertebrae and some skull bones.

Pneumatic bones

Bones with air spaces in them. These include certain bones of bird. Absent in dogs.

aberrant long bones

Ribs are what type of bone?

Sesamoids

Are bones which are developed in tendons to afford increased leverage. Examples are the patella and the navicular bone.

Compact (dense or cortical) bone

the hard layer that constitutes the exterior of most bones and forms almost the entire shaft of long bones.

Cancellous (spongy) bone

composed of spicules arranged to form a porous network. The spaces are usually filled with marrow.

Medullary cavity (marrow cavity)

the space surrounded by the cortex of a long bone. In young animals it is filled with red marrow (hematopoietic tissue), which gradually is replaced by yellow marrow (fat) as the animal ages.

Epiphysis

proximal epiphysis

distal epiphysis

Refers to either end of a long bone. The end closest to the body is the , and the end farthest from the body is the .

Diaphysis

The cylindrical shaft of a long bone between the two epiphyses.

Metaphysis

The flared area adjacent to the epiphysis.

Epiphyseal cartilage or disk (physis)

A layer of hyaline cartilage within the metaphysis of an immature bone that separates the diaphysis from the epiphysis. This is the only area in which a bone can lengthen.

Articular cartilage

A thin layer of hyaline cartilage that covers the articular (joint) surface of a bone.

Periosteum

A fibrous membrane that covers the surface of a bone except where articular cartilage is located.

Head

Condyle

Trochlea

Facet

Articular Projections:

Head

Spherical articular projection

Condyle

Approximately cylindrical articular mass

Trochlea

Pulley-like articular mass

Facet

Relatively flat articular surface

Process

Tuberosity (tuber)

Tubercle (tuberculum)

Spine

Crest

Neck

Line (linea)

Non-Articular Projections:

Process

General term for bony projections

Tuberosity (tuber)

Relatively large non-articular projection

Tubercle (tuberculum)

Smaller projection

Spine

Pointed projection or ridge

Crest

Sharp ridge

Neck

Cylindrical part of bone to which a head is attached

Line (linea)

Small ridge or mark on bone

Fovea

Glenoid cavity

Notch

Articular Depressions:

Fovea

Small depression (may be articular or not)

Glenoid cavity

Shallow articular concavity

Notch

Indentation (may be articular or not)

Fossa

Foramen

Canal

Non-articular Depression:

Fossa

Large non-articular depression

Foramen

Circumscribed hole in a bone

Canal

Tunnel through one or more bones