A Closer Look At Total Ankle Replacement Revision
When Aseptic Osteolysis Involves The Tibial Component
When it comes to aseptic osteolysis about the tibial tray without subsidence, one should resect all cyst contents and proceed to implant multiple 0.062-inch Kirschner wires bent and twisted into geometric shapes within the osseous defect with subsequent insertion of polymethylmethacrylate cement (see photos F-H on page 54). Aseptic osteolysis about the tibial tray with subsidence remains a challenge. The only options are explantation and conversion to the INBONE® Total Ankle Replacement Systems (Wright Medical Technology) (see photos on page 56) or when more bone remains, coversion to the Salto Talaris™ Total Ankle Prosthesis (Tornier) or tibio-talo-calcaneal arthrodesis with bulk femoral head allograft and retrograde compression intramedullary nail fixation.45,48,84-86
Once the Salto Talaris® XT Revision Total Ankle Prosthesis (Tornier) is available for use in the U.S., the options for revision total ankle replacement will become more plentiful as this system includes stemmed tibia and talar components, augmented talar components, and a large array of thick UHMWPE inserts.
How To Address Aseptic Osteolysis That Affects The Talar Component
Aseptic osteolysis involving the talar component occurs in three stages of severity based on the degree of collapse into the talar body (see above radiographs) and seems to be correlated with the degree of osseous ongrowth to the porous coated undersurface of the talar component and keel/peg design characteristics.87-89 The options for revision of the talar component depends on whether the failed system was an Agility or Agility LP Total Ankle Replacement System. The original, flanged and posterior augmented talar components are no longer available for use.30
We should note that the LP talar component has the same height as the same size original, flanged or posterior augmented talar components. However, the articulating top surface of the LP talar component is much broader than these other designs and results in comparably less frontal and transverse plane motion. Additionally, depending on the size you use, the revision talar component adds between 1.5 mm and 2.8 mm of height.
Finally, several UHMWPE insert options exist depending on the specific version of the Agility or Agility LP Total Ankle Replacement System undergoing revision. Specifically, if the failed system is an Agility Total Ankle Replacement System, then the revision options include: (1) a same size revision talar component with a bottom-loaded full or half-column 0 mm UHMWPE insert; (2) a same size revision talar component with a bottomloaded full column +2 mm UHMWPE insert; or (3) a same size LP talar component with a bottom-loaded full column +2 mm UHMWPE insert.
However, if the failed system is an Agility LP Total Ankle Replacement System, then one may consider the following revision options.