The foundation is a vital element that determines the strength and endurance of any structure. The human body is one of the most well-built structures exisiting, and the feet are the very foundation that keeps us upright, stable and mobile. The feet is one of our main sources of support, as the whole body rests on them when we are upright. It is also one of the key features of our mobility.
The bones of the foot are an important feature of the feet. The bones that make up the foot include, seven tarsal bones, five metatarsal bones and the phalanges. All these bones are palpable. The tarsal bones are grouped into two: proximal tarsal bones and distal tarsal bones.
Tarsal BonesCredit: http://www.orthopediatrics.com/docs/Guides/tarsal_condition.html
Proximal tarsal bones are made up of three bones (talus, calcaneus and navicular bones) which are not arranged in a row. The distal tarsal bones are made up of four bones (the cuboid bone and the three cuneiform bones ) which are arranged in a row. The medial, lateral and intermediate cuneiform bones articulate with the first three metatarsal bones distally.
There are five metatarsals that form the main skeleton of the foot. Each metatarsal bone contains a proximal base, a shaft, and a distal head. The base of the metatarsal are in contact with the distal row of carpal bones, forming the tarsometatarsal joint. The first, second and third metatarsals articulate with the first, second and third cuneiform bones respectively. The fourth and fifth metatarsals articulate with the cuboid bone. An important condition concerning the bones of the foot is Morton’s toe, a congenital shortening of the first metatarsal.
There are two phalanges for the great toe and three phalanges each for the second to fifth toes. The head of the metatarsal is in contact with a proximal phalanx, forming the metatarsophalangeal joint. The middle phalanges articulate with the proximal row of phalanges at the proximal interphalangeal joints. The middle phalanges also articulate with the distal row of phalanges at the distal interphalangeal joints.
Muscle InsertionCredit: http://www.zaskmedical.com/anatomicalfoothand.htm
Bones also important because they are the areas of muscle insertion, which allows body parts to move. The bones are the areas of support, while the muscles provide the energy and force for movement. For example, the base of the proximal phalanx of the great toe is important because it is the insertion of the abductor hallucis, whose function is to abduct the great toe. Foot and ankle dorsiflexors include the tibialis anterior, extensor hallucis longus and extensor digitorum longus. The tibialis anterior is inserted in the medial cuneiform and in the base of the 1st metatarsal. The extensor hallucis longus is inserted in the base of the base of the distal phalanx of the great toe while the extensor digitorum longus is inserted in the middle and distal phalanges of digits two to five. Weakness in these groups of muscles can lead to the steppage gait, wherein the foot characteristically slaps to the ground. Damage to these muscles or the nerves supplying them also leads to foot drop.
The foot may be a neglected part of the body, but it is of utmost importance. The basics have been covered here, but like any anatomical structure, the foot is complex. There is more to know and discover about the bones of the foot.