Morphometric analysis of metacarpophalangeal and proximal interphalangeal palmar plates

Palmar plates are being used as a source of graft in radial or ulnar collateral ligament reconstruction, pulley reconstruction, and volar plate arthroplasty. The purpose of this study is to determine morphometric and major histological differences of palmar plates in metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints among fingers, and supply sufficient data which would be useful in reconstruction procedures. Ninety-six MCP and 96 PIP palmar plates of 12 well-preserved formalin-fixed cadavers were measured focusing on their length, width, central thickness, and lateral thickness and statistically analyzed using ANOVA. Randomized three male and three female cadavers' specimens were examined histologically after staining with Masson's trichrome. For central thickness of the PIP joint level, there was significant difference among fingers, caused by the middle and little fingers. For lateral thickness of the PIP joint level, there was significant difference which was originated from little fingers. MCP palmar plates were significantly thicker than PIP joint levels for most of the fingers. There were thicker and denser collagen bands in MCP than PIP palmar plates. The relation of size-related parameters was not close with the thickness parameters. The predicted sizes and thicknesses of palmar plates vary according to fingers. The data collected for each finger in this study should be used as a guide in reconstructive procedures that use palmar plates as source of graft.