The whole body weight is transmitted through the hips and knees to both ankles. The ankle joint resembles an inverted wrench and is comprised of the lower leg bones ( Tibia and Fibula) and the Talus bone and is supported by strong ligaments and muscles.
Strong ligaments support the lateral ( outer) aspect and Medial (inner) aspect of the joint. The ligaments of the lateral aspect attach the lateral malleolus ( lower end of fibula) to the talus and calcaneous bones. These ligaments are very strong that in certain cases avulsion fracture ( fracture of the attachment site of the ligament on the bone) before these ligaments fail and completely torn. These ligaments are:
Anterior Talofibular Ligament
Posterior Talofibular Ligament
This group of ligaments situated on the lateral side of the joint helps to stabilize the lateral side and to prevent excessive supination ( inward movement) of the foot.
The ligaments of the Medial side of the ankle joint form a group known as “ Deltoid Ligament”. It is composed of the following ligaments:
Anterior Tibiotalar ligament
Posterior Tibiotalar Ligamnt
The foot is the most distal (situated away) part of the weight bearing chain. The body weight is transmitted from the hips, knees to both feet. This body weight is divided between the heel and the toes. 50% of the weight is transmitted to the heel while the rest of the weight is transmitted to the forefoot. Any alteration of this distribution of weight will result in serious consequences not only affecting the foot but also affects the knee, hip and the back. The weight distribution is governed basically by the shape of foot.
The foot is divided into three parts: Forefoot, Midfoot and Hindfoot (rearfoot).
The forefoot is comprised of the five metatarsals, 14 phalanges and associated soft tissue structures.
The midfoot consists of the three Cuniform bones, Cuboid and Navicular bones.
The Hindfoot contains the Talus and Calcaneus bones.
Several arches give the foot its shape: Medial arch, Longtudinal arch, Lateral arch and Transverse arches.
The medial arch is comprised of the Calcaneus, Talus, Navicular, Cuniform bones and the first, second and third metatarsals.
The Lateral arch is lower than than the medial arch and is comprised of Calcaneus, Cuboid and the 4th and 5th metatarsal bones.
The transverse arches are formed by the Cuniform bones, Cuboid and the bases of 5 metatarsals.
These arches are what gives the foot the optimal shape capable of bearing the body weight. They are maintained and supported by strong ligaments and tendons.
The medial arch the most important among other arches of the foot. In some cases the arch is lost or reduced which results in a Flat Foot and in other cases the arch is exaggerated forming a High arch.
The foot when viewed posteriorly (from the back) the position of the Calcaneus bone must be in a perpendicular line with the Achillis tendon.
Foot abnormalities are either congenital ( since birth ) or acquired. Attention should be paid to shape of the foot as abnormalities won’t affect the foot only it well result in compensations that moves up along the chain to the knee, hip and the back.