Marked cannula

摘要

A marked cannula is disclosed that provides for first and second indicia for marking positions along the inner surface of the cannula. The first and second indicia are distinctive with respect to each other and are easily detected or visible using an endoscope. The first and second indicia are preferably provided at positions that are representative of the general population in terms of location of the plantar fascia. The indicia provide a quick visual reference for the positioning of a surgical instrument within the bore of the cannula.