Thanks-giving is a pleasant job, but it is none the less difficult when one sincerely tries to put them in words. These humble words, expressions and gratitude cannot really convey the deep feelings of my heart.

With high-esteem and profound regards, I take the privilege to acknowledge my sincere gratitude to my worthy husband, Engineer Bhavneesh Malik, Assistant Professor, Vaish College of Engineering, Rohtak, Haryana, India, for carving another milestone in my academic journey. His painstaking efforts in suggesting, designing, advising, and improving the book throughout the entire span and for his inexhaustible encouragement, has enabled me to complete the book satisfactorily. I have no words for expressing my gratitude to him for the affection and love, he showered on me, his endless support, unfailing attention and constant inspiration because of which I was able to undertake this endeavor successfully.

With utmost regards, I am thankful to my parents and family members for their suggestions, help and constant moral support throughout this period which enabled me to complete the book.

I feel highly obliged and deeply honored to express my profound regards and true expressions of respect to Dr Dhruva Chaudhary, Professor and Head, Department of Pulmonary and Critical Care Medicine, Pt Bhagwat Dayal Sharma Postgraduate Institute of Medical Sciences, Rohtak, Haryana, India, for his unceasing guidance and kind help. His initiative and interest have taught me a sense of professional duty and pride.

At this juncture, I would like to express my deepest heartful gratitude to Jain Book Depot, Rohtak, Haryana; M/s Jaypee Medical Publishers (P) Ltd, New Delhi; Gaur Brahman Physiotherapy College, Rohtak, Haryana; Faridabad Institute of Technology (FIT), Faridabad, Haryana; and Shri Baba Mast Nath College of Physiotherapy, Rohtak, Haryana, India, for their cooperation, teaching and moral support that helped me to tide over occasional moments of distress.