Footwear Engineering-I Chapter: Human Foot Lecture No.-01 Prepared & Delivered by: Md. Samsul Arefin Assistant Professor Dept. of Leather Engineering Khulna University Of Engineering & Technology(KUET) Khulna-9203,Bangladesh

About Foot: You’ve heard the phrase: “I have one foot bigger than the other”. A closer truth would be: “no two feet are alike”, and yes in many cases one foot is larger than the other. Handling the challenge of properly fitting and advising customers on their shoe choice starts with the basics; the human foot. You are a “foot fitter” before you are a “shoe fitter”

All About foot  Average adult people take to steps a day.  Kids take even more steps than the above.  Most feet walk miles In one’s lifetime- which is four times around the earth.  Foot consists of 26 bones, 19 muscles, over 100 ligaments.  Every time when foot strikes the floor during walking, ground reactive force strikes back almost equivalent of twice one’s body weight. While running, this pressure multiple up to three times your body weight.

 The foot has 250,000 sweat glands which release about a quarter pint of perspiration every day. (1 quarter US pint = milliliters)  Approximate 70% of foot problems occur from wearing ill-fitting or wrong footwear. Majority of such damages took place due to wrong shoe worn as a child.

Foot: The lower extremity of the leg that is in direct contact with the ground in standing or walking. The part of the leg of a human being below the ankle joint. The great Michelangelo once described the human foot as “a work of art and a masterpiece of engineering.” In Depth: Foot The foot is the lowest point of the human leg. The foot’s shape, along with the body’s natural balance-keeping systems, make humans capable of not only walking, but also running, climbing, and countless other activities.

What is so unique about the human foot? It is the only foot in nature with a heel bone that touches the ground; that has a straight ahead big toe and that has an arch. These unusual features have enabled us to stand and walk upright on two feet with a stride- a feet never achieved by any other creature. This remarkable accomplishment was responsible for changing our entire anatomy.Hence, foot is called amazing organ.

Pic: Human Foot

Function of Foot: The human foot is an incredibly complex mechanism that has two very important functions:  Weight bearing: Supporting the weight of the body and keeping it properly balanced in an erect position.  Propulsion (movement): Propelling the body forward. In order to perform these functions, the foot requires a high degree of stability as well as flexibility. The multiple bones and joints of the foot give it the necessary flexibility, but in order to fully support any weight, the bones of the foot need to form an arch.

Foot anatomy Foot anatomy consists of : 1. Primary parts 2. Additional parts 1. Primary parts:  the bones  joints  ligaments  muscles and tendons  arches  nerves  and blood systems

2. Additional parts:  The sweat glands  Bursae  Skin and nails

Names of toes Names of five toes of human foot: 1.Hallux ("big toe" or "great toe") 2.Second toe or "long toe“ 3.Third toe, or "middle toe“ 4.Fourth toe, or "ring toe“ 5.Fifth toe ("little toe", "pinky toe", or "baby toe.)

Bone structures The human foot is a highly developed, biomechanically complex structure that serves to bear the weight of the body as well as forces many times the weight of the human body during propulsion. About 26 bones in the human foot provide structural support. They can be grouped into 3 parts, as follows : 1. The tarsal bones (7) 2. The metatarsal bones (5) 3. The phalanges (14)

Top view of foot skeleton

Apart from these main bones, the sesamoid bones help improve function and are often found as variants of the accessory bones. 1.The tarsal bones (7): a)Oscalcis ( calcaneum)-1 piece b)astragalus(talus)-1 piece c)Cuboid-1 piece d)Scaphoid(navicular)- 1 piece e)Cuneiforms- 3 pieces: (Inner, middle & outer)

2. The metatarsal bones (7): Composed of 5 metatarsal bones 3. The phalanges (14): Consists of fourteen bones in the toes. They are three types such as:  Distal phalanges(5)  Middle phalanges(4)  Proximal phalanges(5)

Side view of foot skeleton

Regions of the foot The feet are divided into three sections:  Fore-foot – The forefoot contains the five toes (phalanges) and the five longer bones (metatarsals).  Mid-foot – The midfoot is a pyramid-like collection of bones that form the arches of the feet. These include the three cuneiform bones, the cuboid bone, and the navicular bone.  Hind-foot – The hind foot forms the heel and ankle. The talus bone supports the leg bones (tibia and fibula), forming the ankle. The calcaneus (heel bone) is the largest bone in the foot.

Fig: Foot Arch

Important Reference Books 1. Manual of Shoe making R.G. Miller 2. Introduction to Modern Footwear Technology Venkatappaiah B. 3. Footwear Materials and Process Technology A.J. Harvey 4. Professional Shoe Fitting ---- Pedorthic Footwear Association 5. The Complete Footwear Dictionary William A. Rossi 6. The Innovation Notebooks for the Footwear Industry ---- Edited by Assomac

Thanks for Concentration!