Articular capsules of proximal interphalangeal joints of foot
Capsulae articulares articulationum interphalangearum proximalium pedis
The capsules enclosing the hinge joints between the proximal and middle phalanges of the second to fifth toes.
At a glance
- English
- Articular capsules of proximal interphalangeal joints of foot
- Latin (TA2)
- Capsulae articulares articulationum interphalangearum proximalium pedis
- System
- Joint
- Region
- Foot
- Side
- Paired, left and right
About the articular capsules of proximal interphalangeal joints of foot
In each lesser toe the proximal interphalangeal joint joins the pulley-shaped head of the proximal phalanx to the base of the middle phalanx. It is a hinge joint, and its capsule, a fibrous sleeve lined with synovial membrane, attaches near the edges of both articular surfaces.
The dorsal part of each capsule is thin and blends with the extensor expansion formed by the tendons of extensor digitorum longus and brevis. The sides are strengthened by collateral ligaments. The plantar part is thickened into a plantar ligament, or plate, which lies under the joint and over which the long and short flexor tendons pass. The tendon of flexor digitorum brevis splits around the long flexor tendon here and inserts on the sides of the middle phalanx.
The joints allow the toes to bend and straighten at their middle knuckle, with flexion freer than extension. They are the site of hammer toe, the commonest deformity of the lesser toes, in which the joint is held bent while the joints on either side are straight or extended. The dorsal knuckle then rubs on the shoe and a corn forms over it. Over time the dorsal capsule stretches and the plantar structures shorten, so the deformity may become fixed. Claw toe, with bending at both interphalangeal joints and extension at the metatarsophalangeal joint, also involves these capsules.
Attachments and function
- Formed by
- Margins of the articular surfaces of the heads of the proximal phalanges of the second to fifth toes.
- Joins
- Margins of the articular surfaces of the bases of the corresponding middle phalanges.
- Movements
- Enclose and stabilise the hinge joints at the middle of the toes, allowing flexion and extension.
- Nerve supply
- Plantar and dorsal digital nerves of the toes.
- Blood supply
- Plantar and dorsal digital arteries of the toes.
Anthromica
See the articular capsules of proximal interphalangeal joints of foot where it really sits, with every layer of the body around it.
- Every layer, one body. Peel from muscle to bone, nerve, vessel and organ, and turn it any way.
- English and Latin. Every structure named the way your exam names it.
- Quiz until it sticks. Short drills on the structures you keep missing.
Free to start. No card.
