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The Postnatal Development of the Feline Distal Phalanx
Author(s) -
Bragulla Hermann H.,
Homberger Dominique G.
Publication year - 2010
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.24.1_supplement.454.3
Subject(s) - anatomy , phalanx , ossification , claw , dorsum , process (computing) , medicine , biology , ecology , computer science , operating system
In adult cats, the distal phalanx consists of (1) a proximal articular base articulating with the middle phalanx and bearing a palmar flexor tubercle and a dorsal extensor process for the attachment of tendons; (2) a distal unguicular process supporting the cornified claw sheath; and (3) an unguicular hood cupping the proximal part of the unguicular process and anchoring the cornified claw sheath. The postnatal development of this complex was analyzed with light microscopy, SEM, and x‐ray CT. The tomography data were reconstructed with OsiriX. In newborn cats, the distal phalanx consists only of a cartilaginous articular base, a peri‐ and enchondrally ossifying unguicular process, and a growth plate between them. At this stage, the unguicular hood consists only of fibrous connective tissue. At about six months, the hood starts to ossify at its base on either side of the articular base. At about twelve months, the hood is almost completely ossified, except for a small proximodorsal gap. By 22–24 months, the hood is fully ossified. The delayed desmal ossification of the hood allows the cartilaginous dorsal extensor process to complete its growth while the dorsally overarching hood is still expandable.