Fig. 2

The central portion of the plantar plate and intersesamoid ligament of the first MTPJ from a left foot specimen (33 years old). a Midsagittal schematic diagram of first MTPJ; b sagittal anatomic slice; c sagittal T1WI image of the MTPJ; d sagittal PD-FS image of the MTPJ. White curved arrow: The central portion of the plantar plate coursed from metatarsal neck (white short arrow) to the proximal phalangeal base. Note a normal, smooth, well-defined distal recess (arrowhead) at the insertion of the proximal phalangeal base of the central portion of the plantar plate. (The white long arrow = flexor hallucis longus tendon; White triangle = The intersesamoid ligament). e and f HE and Masson’s trichrome staining of the first MTPJ (original magnification ×4). The white short arrow and arrowhead: the proximal and distal attachment of the central portion of the plantar plate. g and h HE staining of the central portion of plantar plate and the intersesamoid ligament; They appeared interwoven with the same continuous collagenous fibers that with a small number of chondroid metaplasia (HE, original magnification × 200). (FHL = flexor hallucis longus tendon; IS = intersesamoid ligament; MT = metatarsal; P = phalanx; PP = central portion of the plantar plate.)