**Acknowledgements**

I would like to thank the authorities of Dr. MGR Educational and Research Institute, University, Honorable chairman Dr. AC. SHANMUGAM, Honorable president ACS. ARUNKUMAR, Honorable secretary Thiru A. RAVIKUMAR and our Principal, Faculty of Physiotherapy Dr. CV. SENTHIL NATHAN for providing facilities required to complete the chapter with their support and guidance. With great privilege I thank my husband Er. S Elangovan and my mother for their support and motivation.
