Structure
This fibrocartilaginous structure is attached to the base of the proximal phalanx distal to the joint. From there, it forms a palmar continuation of the articular surface of the phalanx bone and its inner surface thus adds to the articular surface during extension.
In its proximal end, the volar plate becomes membranous and blends with the volar capsule which is attached to the head of the metacarpal bone. During flexion, the plate glides proximally down the volar surface of the metacarpal head. Its flexible attachment to the phalanx bone not only prevents it from restricting joint movements, but also prevents the long flexor tendons from being pinched in the joint. Flexion of the proximal phalanx is facilitated by the shape of the proximal edge, known as the volar recess, but this diaphanous end of the volar plate is also the part of the metacarpophalangeal joint that is most susceptible to injury during dislocations.
Due to its fibrocartilaginous composition, the plate is thus able to (1) resist tensile stresses while (2) restricting hyperextension and compression and (3) protecting the volar articular surface.
Read more about this topic: Palmar Plate
Famous quotes containing the word structure:
“Agnosticism is a perfectly respectable and tenable philosophical position; it is not dogmatic and makes no pronouncements about the ultimate truths of the universe. It remains open to evidence and persuasion; lacking faith, it nevertheless does not deride faith. Atheism, on the other hand, is as unyielding and dogmatic about religious belief as true believers are about heathens. It tries to use reason to demolish a structure that is not built upon reason.”
—Sydney J. Harris (1917–1986)
“Each structure and institution here was so primitive that you could at once refer it to its source; but our buildings commonly suggest neither their origin nor their purpose.”
—Henry David Thoreau (1817–1862)
“Why does philosophy use concepts and why does faith use symbols if both try to express the same ultimate? The answer, of course, is that the relation to the ultimate is not the same in each case. The philosophical relation is in principle a detached description of the basic structure in which the ultimate manifests itself. The relation of faith is in principle an involved expression of concern about the meaning of the ultimate for the faithful.”
—Paul Tillich (1886–1965)