skeletal system 3

Haversian system

The structural unit of bone tissue.

Osteon

Another name for Haversian system.

Haversian canal

Little tunnels in the bone that contain blood vessels.

Lamellae

Concentric layers of bone tissue surrounding the Haversian canals.

Osteocytes

Bone cells that live in lacunae.

Lacunae

Little holes in bone where osteocytes live.

Matrix

Non-living substance between cells, especially in cartilage and bone tissue.

Canaliculi

Tiny tunnels between lacunae that provide a way for cytoplasmic processes of osteocytes to contact each other.

Organic matrix

A component of bone matrix that includes osteoid; needed for flexibility.

Inorganic matrix

A component of bone matrix mainly consisting of calcium; needed for rigidity and strength.

Osteoblasts

Cells that form new bone.

Osteoclasts

Cells that resorb bone.

Non-union

Improper healing of a fracture; it healed, but in pieces.

Callus

A bone scab formed during the healing of a fracture.

Rickets

Bone deformity occurring in young animals due to lack of vitamin D.

Fracture reduction

Putting the bone back together as close to normal as possible.

Ossification

Calcium deposition for normal bone formation.

Calcification

Calcium deposition in an abnormal location.

Closed fracture

A fracture where the skin over the site is unbroken.

Open fracture

A fracture where the skin has been broken and the bone is exposed.

Greenstick fracture

A fracture that does not go completely through the bone.

Transverse fracture

A fracture that is straight across the bone.

Oblique fracture

A fracture that is diagonally across the bone.

Comminuted fracture

A fracture that results in several small fragments.

Physeal fracture

A fracture through a growth plate in a young animal.

Factors affecting fracture healing

Important considerations include blood supply, immobilization, and age of the patient.

Nutrient artery

The hole in a bone where a blood vessel normally enters.

Immobilization importance

Prevents any movement that can break down healing.

External fixation

Reducing and immobilizing a fracture without surgery.

Internal fixation

Surgical repair of a fracture, using methods like IM pins, plates, or screws.

Callus formation

Initial stage of fracture healing involving blood clot formation.

Callus vascularization

Stage involving blood vessels growing into the callus.

Callus ossification

Calcium deposition in the callus making it visible on a radiograph.

Callus reorganization

Remodeling of the bone by osteoclasts and osteoblasts to strengthen the fracture site.