This document provides an overview of key concepts in basic sciences related to biomaterials, bone, cartilage, and osteoporosis. It defines a biomaterial as any synthetic or natural substance used to treat, augment or replace tissues in the body. It describes the microscopic and macroscopic structure of bone, including its cells, matrix, and types of formation. Bone remodelling and its causes and process are also summarized. The document further discusses osteoporosis, epiphyseal injuries, cartilage types and constituents, and age-related changes to cartilage.
3. • BIOMATERIAL
• Any substance or combination of substances
,synthetic or neutral ,that can be used for any
period of time to treat ,augment or replace any
tissue organ or function of the body.
• Exhibit viscoelasticity, creep and stress relaxation.
4. • Definitions:
• Load: forces that act on the body
(tension,compression,shear,torsion)
• Deformation: a temporary (elastic) or permanent
(plastic) change in the shape of the body.
• Elasticity: ability to return to the resting length after
undergoing shortening or lengthening
• Energy: ability to perform work
5. • Force: A mechanical push or pull (load)
causing external (acceleration) or internal
(strain) effect.
• - compression force shrinks the body in the
direction of the force.
• - tensile force elongates the body
6. • Stress:
• - is the intensity of the internal force.
• Stress= force/area
• Is the internal resistance of a body to a load
• Stress= n/m” (pascals)
• Ultimate stress is the stress at failure from a
single loading cycle or pull.
7. • Strain:
• Is the measure of deformation of a body as a result
of loading
• Strain = change in length/original length
• Strain is proportional and has no units
26. Types of bone
Lamellar bone Cortical (80% Skeleton)
Cancellous (Lower E)
Woven bone Immature (# Callus, embryonic bone)
Pathological
______________________________________________
Function Mechanical
Haematological
Ca Homeostasis
27. Bone Matrix
• Organic (40%) Collagen Type 1 (90%)
(Holes and pores)
Proteoglycans
Matrix proteins
Growth factors, cytokines
• Inorganic (60%)Hydoxyapatite
Brushite
38. Epiphyseal Injuries + Growth arrest
• Trauma (80%)
• Infection
• Tumour
• DXT , Burns
• Distal femur – Prox Tibia – Distal radius
• SH I, II, III, 5%
• SH IV 85%
• SH V ???
41. • Primary osteoporosis is a metabolic bone
disease characterized by low bone mass and
microarchitectural deterioration of bone
tissue, leading to enhanced bone fragility and
increased fracture risk
– Type I postmenopausal
– Type II age related
43. • Normal bone: T-score better than -1
• Osteopenia: T-score between -1 and -2.5
• Osteoporosis: T-score less than -2.5
• Established osteoporosis includes the presence of a non-traumatic fracture.
The Z-score is the number of standard deviations below age-matched avereage.