Anatomy and Biomechanical of Bones and Articular Cartilage

Anatomy and biomechanical of bones and articular cartilage
University
Name
Date

Introduction
Bones and cartilages are key specialized forms of connective tissues that are
composed of cells in the extracellular matrix site. They play an important role
in the protection of internal organs and providing support on the surfaces of
attachment muscles. Bones are composed of high connective tissues that
form a vertebrate skeleton. They comprise of blood vessels and cells. New
borne have an estimate of 300 bones which reduced overtime to 206. The
key functions entail storage purposes for minerals, structural support and
protection of internal organs in the body (Rehfeld, Nylander and Karnov,
2017). Cartilages are thin fibrous connective tissues majorly found in
respiratory tract ear, larynx and surface joints of articulars. The cartilages are
not supplied with blood hence their growth and development are lower
compared to that of other tissues. There are majorly three types of cartilages;
hyaline cartilage which acts as a shock absorb and allows smooth bones and
joints movements, fibrocartilage located in the knee are tough and inflexible
and elastic cartilages found in-ear, epiglottis, and larynx. It is one of the most
flexible cartilages (Ripamonti, 2018).
Bone
Bones comprise of rigid tissues which are made up of collagen and calcium
phosphate like materials. It is made of connective tissue that assembles and
forms bones and skeletons. The human body contains an estimate of 206
separate bones. The largest bone structure is femur while the smallest bone
is stapes, located in the ear. Bones occur in different shapes in the body.
Further, about 99% of the bones in the body are found in the bones and teeth
while 1% is found in blood (Zura et al., 2016).
The human skeleton is an essential framework for the body, it contains two
key subdivisions each which are different from each other and present
certain individual features. They entail the axial having the vertebral column
detailing the spine and skull. The other subdivision is appendicular attached
to the pelvic girdles and bones and cartilages in their location. The skeleton
subdivision harbors the nervous system, respiratory system, digestive

system, cardiovascular system, and the muscular system. The underlying
function f skeletons are to protect, support and motion (Gao, Fang, Gong and
Gao, 2017).
Bone cells
Bones cells are referred to as osteoblasts and osteocytes while others are
osteoprogenitor cells and osteoclasts. The extracellular matrix is made up of
organic matrix which entails 30% having proteoglycans, glycosamine,
glycoprotein, osteocalcin, and osteonectin. Further, the collagen fibers
comparing of type 1 with 90% and type V. About 25% of the bones is water
while the rest is made up of bone mineral deposits (Zura et al., 2016).
Bone structure / development
Bones are strong structures that are flexible and semi-rigid facilitating
supporting tissue, they can withstand compression forces and it can bend
(Safadi et al., 2009). Before the calcification of the matrix, the tissue is referred
to as osteoid. Increased concentrations of calcium and phosphate ions are
deposited in the extracellular matrix leading to calcification of the bones.
Impairment of calcification leads to an increase of osteoid tissue compared to
normals. Calcification occurs with an increase of collagen fibers through salts
crystallization on the fiber spaces leading to accumulation (Gibbs, 2017).
Bones are resistant to twisting, compression, bending and stretching. It is
often hard due to the calcification process, the collagen aids in the resistance
of tensile stresses. Dissolution of the bone calcium often leads to rubbery
structures due to collagen fibers present in the bone structure (Rauch, 2012).
Bone type organization and tissue

Figure 1 Illustrative process of bone type
The first bone formed is woven however it is replaced by lamellar bone. The
woven bone cartilages are random while in lamellar bones the collagen fiber
remodels to be in parallel layers. Mature bones occur in two avenues;
compact and spongy. The compact bones are located in the shafts making up
80% of all bone (Figueroa and Lee, 2019).
Spongy bones are found at the end of long bones referred to as epiphysis and
make 20% of all bone make up. The periosteum is found outside bones, it is a
dense fibrous layer for muscles insert. It entails cell formation and not found
in the region of articular cartilage (Lozano et al., 2016).
Bone functions
Bones are essential in movement. The bone joints facilitate movements
offering an allowance for wide range steps than others. Bones offer
protection, the skeleton offers an avenue for the protection of various internal
organs. Bone role in production of cells play an active role in production of
haematopoiesis on blood cells. Bones are essential aspect of storage. The
bone matrix offers storage for calcium which is involved in its metabolism.
Bones offer support framework essential for body and shape maintenance
(Cowan and Kahai, 2019).
Biomechanical properties of bone