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In the human hand, palmar or volar plates (also referred to as palmar or volar ligaments)〔In older literature they are also known as the glenoid ligaments of Cruveilhier or vaginal ligaments.〕 are found in the metacarpophalangeal (MCP) and interphalangeal (IP) joints where they reinforce the joint capsules, enhance joint stability, and limit hyperextension. The plates of the MCP and IP joints are structurally and functionally similar, except that in the MCP joints they are interconnected by a deep transverse ligament. In the MCP joints, they also indirectly provide stability to the longitudinal palmar arches of the hand. 〔 (MCP joints)〕〔 (IP joints)〕 The volar plate of the thumb MCP joint has a transverse longitudinal rectangular shape, shorter than those in the fingers. == 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. 〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Palmar plate」の詳細全文を読む スポンサード リンク
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