Anatomic study of arthroscopic portal sites of the ankle

Numerous anatomic structures are at risk when performing ankle arthroscopy through the more commonly utilized portals. The purpose of this paper was to demonstrate the relative safety of each of the arthroscopic portal and Acufex external ankle distractor pin sites by measuring their proximity to the neurovascular structures surrounding the ankle joint. Six fresh cadaver specimens and 12 fresh-frozen, below-knee amputations were utilized for this study. An Acufex ankle distractor was applied using the standard technique. Anteromedial, anterolateral, anterocentral, posterolateral, and posteromedial portals were placed using an 11-blade scalpel to make 5-mm longitudinal incisions. The joint capsule was penetrated and a 3-mm arthroscope was placed into the ankle joint. The skin surrounding each of the portals was carefully removed and the proximity of any nerves or vessels was measured with respect to the arthroscope. At least one incidence of contact or penetration of a nerve or vessel was noted for each site. The anterocentral portal was at greatest risk for nerve or vessel damage. The anterolateral, anteromedial, and posterolateral portals were the safest areas for portal placement, with no penetration of neurovascular structures in any case.