Tarsometatarsal joint
The tarsometatarsal joints ( Articulationes tarsometatarsales , "tarsal-metatarsal joints", abbreviated: "TMT IV") are the joints between the sphenoid bones and the cuboid bone and the bases of the metatarsal bones . It is tight joints ( amphiarthroses ), that is, they can only slight movements. With higher loads, they are involved in the tilting movements of the foot ( pronation and supination ). In humans, a distinction is made between three tarsometarsal joints, the joint spaces of which form the Lisfranc joint line.
The sphenoid bones form a kind of transverse arch in which the base of the second metatarsal bone is firmly anchored as a keystone. The base of the second metatarsal bone extends much further proximally than the neighboring metatarsal bones and is firmly connected to the medial sphenoid bone, especially via the Lisfranc ligament. Near the base, some metatarsal bones are connected by intermetatarsal joints, some of which are in direct contact with the tarsometatarsal joints.
In birds there are no tarsometatarsal joints, here the corresponding bones are fused to form the tarsometatarsus .
Single joints
The inner (medial) tarsometatarsal joint is formed by the inner sphenoid bone ( os cuneiforme mediale ) and the first metatarsal bone. In the middle tarsometatarsal joint, the middle and outer sphenoid bones ( os cuneiforme intermedium and laterale ) are connected to the bases of the second and third metatarsal bones. The outer (lateral) tarsometatarsal joint is formed by the cuboid bone and the fourth and fifth metatarsal bones.
The three joints each have their own joint capsule and are separated from one another by interbone ligaments ( ligamenta interossea ). The articular cavities of the middle and outer tarsometatarsal joints are in communication with those of the adjacent intermetatarsal joints .
clinic
In a hallux valgus -Fehlstellung occurs in the first tarsometatarsal joint to a medial abduction to Fußinnenrand and a varus of the first metatarsal ( metatarsus primus varus ). Correspondingly, some surgical procedures to correct the hallux valgus start at this first tarsometatarsal joint, particularly the lapidus arthrodesis as a corrective stiffening of the joint.
Lisfranc dislocation is a severe but rare foot injury ; in the United States, the incidence is 2 per 100,000 population per year. This can lead to accompanying fractures, especially of the second metatarsal bone. Footballers are at increased risk.
As part of a diabetic foot syndrome or neuro-arthropathy , type II according to Sanders and Frykberg can lead to destruction of the Lisfranc joint.
The Lisfranc joint line can be used to amputate the forefoot.
literature
- Walther Graumann, Rolf Baur: the musculoskeletal system. In: Compact Textbook Anatomy. Vol. 2, Schattauer, Stuttgart 2004, ISBN 3-7945-2062-9 , pp. 199-200.