Anatomical variation of the tibial plafond: the anteromedial tibial notch.

Abstract

An investigation of 77 intact foot and ankle specimens (21 fresh frozen and 62 preserved) was conducted to determine normal anatomical variation of the anteromedial region of the tibial plafond. Lower extremity specimens were obtained and carefully disarticulated at the ankle joint. Care was taken to observe anterior joint capsule attachments along with plafond surface anatomy. Specimens that exhibited signs of previous trauma or significant degenerative arthritic changes were not included in the study. All of the specimens were photographed with a millimeter scale, and the photographs were later evaluated to quantify anatomical variations of the anterior medial tibial plafond. The results of this investigation demonstrated a normal variant of articular notching of the anteromedial tibial plafond. The notching appears to function as a joint capsule anchor. In the more well developed notches, a fold, apparently of synovial tissue, was found. The notching increases the surface area for capsular attachment, is variable in size, and may assist in synovial fluid movement across the joint during ambulation. This articular notching, although often encountered arthroscopically, should be considered a normal anatomical variant unless localized degenerative processes are identified.