Toe joint
The toe joints are the joints in which the toe bones are involved. Mammals have three toe joints on each fully developed toe; the human big toe has two toe joints.
The toe joints are subdivided into the metatarsophalangeal joint ( Articulationes metatarsophalangeae ) between the heads of the metatarsal bones ( Caput ossis metatarsi ) and the respective base of the first phalangis of the toe bones ( base phalangis proximalis ) and the interphalangeal joints ( Articulationes interphalangeae pedis ).
Interphalangeal joints
The fully developed toes have a mid-toe joint (proximal interphalangeal joint, PIP ) and a terminal toe joint (distal interphalangeal joint, DIP ). The middle toe joint is absent on the human big toe - as is the middle phalanx of the toe - on the little toe the bones of the end of the toe are usually fused together ( synostosis ).
The joints each consist of a joint head known as a trochlea ("joint role"), which is formed by the head of the ( caput phalangis ) of the phalanx bone ( base phalangis ), and a joint socket, which is formed by the base of the phalanx bone ( base phalangis ). According to the shape of the joint surfaces, it is a hinge joint . Each toe joint is stabilized on both sides by a collateral ligament ( collateral ligament), and on the back of the foot they are covered by the dorsal aponeurosis . The tight collateral ligaments severely limit the range of motion of the toe joints. The central joints can plantar flexion up to 35 °. Dorsiflexion of up to 30 ° is also possible in the toe joints .
Malposition of the interphalangeal joints
In humans:
In animals:
literature
- Walther Graumann, Rolf Baur: the musculoskeletal system. In: Compact Textbook Anatomy. Vol. 2, Schattauer, Stuttgart 2004, ISBN 3-7945-2062-9 , p. 201.