Joints of the foot
With the exception of the ankle joints, all tarsal joints are amphiarthroses, i.e. “real” joints that have a joint space: Articulatio calcaneocuboidea Articulatio tarsi transversa (Chopart joint line) Here, the talus and heel bone are separated from the tarsal bones located further forward: Articulatio cuneonavicularis Articulatio cuneocuboidea Articulationes intercuneiformes
- Calcaneocuboid articulatio
- Articulatio tarsi transversa (Chopart joint line)
- Cuneonavicular articulator
- Cuneocuboid artery
- Articulationes intercuneiformes
Tight joints strongly bind the metatarsus or its bones: Articulationes tarsometatarsales: tarsometatarsal joints, which are strengthened by tight ligaments, are severely restricted in their freedom of movement. Only the two outer tarsometatarsal joints have slightly more freedom of movement. Articlationes intermetatarsales: This is a “real” joint between the bases of the 2nd – 5th metatarsal bone.
This joint is also secured by taut ligaments and therefore limited in its mobility. – Articulationes tarsometatarsales: metatarsophalangeal joints of the foot, which are reinforced by tight ligaments, are severely restricted in their freedom of movement. Only the two outer tarsometatarsal joints have slightly more freedom of movement.
- Articlationes intermetatarsales: This is a “real” joint between the bases of the 2nd – 5th metatarsal bone. This joint is also secured by taut ligaments and therefore limited in its mobility. The toe joints are so-called diathroses, i.e. “false joints”: Articulationes metatarsophalangea: metatarsophalangeal joints between the metatarsus and the toes.
In functional terms, these are ball joints with 2 degrees of freedom or movement. Articulationes interphalangea pedis: These joints are located between the middle and end joints of the toes. This type of joint is (functionally) a hinge joint.
- Articulationes metatarsophalangea: metatarsophalangeal joints between the metatarsophalangeal and metatarsophalangeal joints of the toes. From a functional point of view, this is a ball joint with 2 degrees of freedom or movement. – Articulationes interphalangea pedis: These joints are located between the middle and end joints of the toes. This type of joint is (functionally) a hinge joint.
Ligamentous apparatus
Similar to the hand, the ligamentous apparatus is complex and consists of many strong, collagenous ligaments. Ligaments originating from the inner ankle form a kind of collagen-fibrous plate (Ligamentum deltoideum) and consist of the following 4 parts and are called the central collateral ligament: Pars tibiotalaris posterior Pars tibiocalcanea Pars tibiotalaris anterior Pars tibionavicularis They all have a common origin at the inwardly directed malleolar fork, a bony protrusion at the lower end of the tibia. Together with the lateral malleolus fork of the fibula, it bifurcates the anklebone.
The beginnings of the ligaments are located at the ankle bone, scaphoid bone and heel bone. Two of them (pars tibiocalcanea & pars tibionavicularis) even have an additional effect on the lower ankle joint. The function of these ligaments is of great importance for the mechanics of the foot.
Thus all four ligaments prevent the foot from valgus. This is a valgus position, i.e. a joint position in which the joint is curved sideways and inwards. A well-known example is the knock-knee position.
In addition, it causes an inhibition of pronation in the lower ankle joint, which corresponds to a lifting of the lateral edge of the foot and a simultaneous lowering of the inner edge of the foot. The 3 lateral collateral ligaments, which start from the outer ankle, are called as follows: Ligamentum talofibulare posterius Ligamentum calcaneofibulare Ligamentum talofibulare anterius As already mentioned, the 3 ligaments also have a common origin. They start at the bony process and neck of the ankle bone and at the heel bone. The Ligamentum calcaneofibulare is the only ligament that has an effect on the lower ankle joint. – Pars tibiotalaris posterior
- Pars tibiocalcanea
- Anterior tibiotalar pars
- Pars tibionavicularis
- Posterior talofibular ligament
- Calcaneofibular ligament
- Talofibular Anterior Ligament
