Adhesions can be considered in two ways: cell adhesions and unnatural adhesions caused by external stimuli. Cell adhesions are complimentary connections naturally found in the human body. Cells are destined to interact with their external environment through cell surface molecules. External environment may be the extracellular material or may be the basement membrane. Basement membrane is an important sheet-like barrier or structure that underlies almost each and every type of epithelium. Basement membrane consists of two types of lamina: basal lamina and reticular lamina. Basal lamina is made upof proteins like collagen type IV and laminin and proteoglycans while reticular lamina is composed of reticular fibers. Cells are adherent through cell junctions and anchor each other. These junctions work as transporters and communicators.
Connective tissue supports epithelial cells and helps other cell functions. It is composed of support cells, guest cells and associated extracellular matrix. Support cells include fibroblasts, myofibroblasts, chondroblasts, osteoblasts and fat cells. Guest cells include macrophages and mast cells. Extracellular matrix consists of certain proteins and other complex molecules made up of mixture of two or more types of molecules. All these cells and matrix perform their vital role to offer functions like storage of energy, protection, provision of structure and shape, connections, transport, nutrition, defense and tissue repair.
On the other hand, adhesions (scarring) are unnatural accumulations of elements in the form of bands which abnormally connect two or more surfaces of tissues and disturb the body functions. Such adhesions may arise from surgical procedures, trauma and radiations during the process of wound repair, especially when the process is unbalanced. These adhesions may be made up of atoms, molecules, cells and tissues. They hinder organ movements, and may block blood supply and nutrition to the organs, causing pain and decreasing organ functioning. Such adhesions are always considered abnormal. In order to get rid of such adhesions or scars and to improve the organ function, one may have to undergo readmission to the hospital, reoperation and painful longer stay at hospital along with extra money loss. More recent modalities offer non-invasive physiotherapy techniques to deal with adhesions.