title: [Menisci and synovial folds of the metacarpophalangeal joint of the thumb].
abstract: The inner surface of 25 thumb metacarpophalangeal joints were investigated and the arrangement and structure of different folds protruding into the joint cavity at the level of the joint cleft studied. At the ulnar and radial sides, compact wedgeshaped folds are found consisting of collagenous fibres, which connect with the fibrous layer of the joint capsule. The circularly arranged fibrous tissue is covered by a thin layer of cartilaginous cells. From a structural and functional point of view they are comparable to the menisci of the knee joint. In contrast, a different kind of tissue is found at the palmar and dorsal circumference of the joint cleft: typical synovial folds, consisting of loose connective tissue and small fat lobules. These are suggested not to fulfill a particular mechanical function but to act as a malleable spacer which is able to conform to the requirements of joint mobility.
authors.affiliation: Lehrstuhl I, Anatomischen Anstalt München.
authors.forename: R V
authors.initials: RV
authors.lastname: Putz
authors.forename: G
authors.initials: G
authors.lastname: Sowa
mesh_terms: D002358:Cartilage, Articular / Q000473:pathology*; D003094:Collagen / Q000648:ultrastructure; D003238:Connective Tissue / Q000473:pathology; D006801:Humans; D008592:Menisci, Tibial / Q000473:pathology; D008662:Metacarpophalangeal Joint / Q000473:pathology*; D016059:Range of Motion, Articular / Q000502:physiology; D012016:Reference Values; D013583:Synovial Membrane / Q000473:pathology*; D013933:Thumb / Q000473:pathology*
chemical_list: D003094:Collagen
vernacular_title: Menisci und Synovialfalten des Daumengrundgelenkes.