DESIGNING NANOFIBROUS SCAFFOLDS FOR TISSUE ENGINEERING - Advanced Biomaterials: Fundamentals, Processing, and Applications - page 458

13.5 TISSUE ENGINEERING USING ELECTROSPUN
NANOFIBROUS SCAFFOLDS
13.5.1 Musculoskeletal System- An Introduction
Musculoskeletal injuries are by far the most common type of injury in sports and
trauma. Recent data reports an increased occurrence of sports and trauma related
musculoskeletal injuries and this rise can be partially attributed to increase in
ageing population [203-205]. It is predicted that by 2020, there will be an increase
in the global ageing population that is expected to lead to a sharp rise in the mus-
culoskeletal disorders in both developed, as well as developing, parts of the world.
This, in turn, could adversely affect the health care system and economy of nations
at large [206,207].
Currently available data indicates that rheumatoid arthritis, osteoarthritis,
osteoporosis, spine disorders and trauma related injuries and disabilities are the
major musculoskeletal conditions that present a signifi cant disease burden on
society [208,209]. Treatment of musculoskeletal impairment has improved with
the current clinical therapies and treatment options. Despite the advances in
clinical research these strategies are limited in terms of improved repair and
regeneration [210]. Therefore, tissue engineering strategies that aim to restore,
maintain or improve tissue function provide an exciting alternative to the existing
treatment modalities [211].
This section of the chapter limits itself to tissue engineering for musculo-
skeletal disorders, with a focus on the use of electrospun nanofi bers as potential
scaffolds for bone, cartilage, skeletal muscle, ligament, and tendon tissue-
engineering.
13.5.2 Tissues of the Musculoskeletal System that Have Been
Engineered Using Electrospun Nanofi bers
13.5.2.1 Bone. After blood, bone is the second most frequently replaced
tissue of the human body. Depending on the functional requirement of the body,
bone tissue has different morphology. Being a dynamic tissue, bone has the ability
to continuously remodel itself without leaving a scar [212]. This well-defi ned
process of remodeling is governed by rapid mobilization of minerals and calcium
phosphate deposition.
Bone homeostasis is attributed to the activities of three cell types:
1 . Osteoblasts - They are the bone forming cells responsible for the synthesis
of the ECM and regulation of its mineralization.
2 . Osteocytes - They are the mature bone cells derived from osteoblasts
and are responsible for maintaining bone tissue by enzyme secretion and
blood - calcium homeostasis.
3 . Osteoclasts - They have the ability to resorb fully mineralized bone tissue
and are responsible for the controlled break down of bone tissue.