AAA Triple A® Components DEsign Features

AAA Triple A® Ankle replacement

  • Surgical alignment with the full leg length axis

  • Minimal resection by precise, spherical milling of the talus

  • Full stability in extension by congruency between tibia and bearing

  • Unrestricted rotation between tibia and bearing

  • Dorsiflexion and plantarflexion between bearing and talar component with increased lateral stability






    • The AAA Triple A® Movements


    AAA Triple A® Ankle replacement

  • Dorsiflexion : 15 degrees


  • Plantarflexion : 20 degrees


  • Unrestricted axial rotation




    • The AAA Triple A® Tibial Components

    AAA Triple A® Ankle replacement

  • Longitudinal oval depression provides semi-constrained rotation between tibial component and bearing

  • Stem provides maximal bone contact and rotational stability, necessary for secondary fixation: bone ingrowth

  • 5 sizes



    • The AAA Triple A® Polyethylene Bearings

    AAA Triple A® Ankle replacement

  • Reduced risk of dislocation by semi-constrained design

  • semi-constrained AP-movements

  • semi-constrained rotational movements

  • highly congruent to the articulating surfaces of the metal counter parts

  • 4 sizes, each with 4 heights: 6, 8, 10 and 12 mm


    • The AAA Triple A® Talar Components

    AAA Triple A® Ankle replacement

  • Anatomical design

  • high initial stability through optimal press-fit

  • spherical contact to the milled talar bone

  • central pegs for optimal fixation and rotational stability

  • minimal bone resection (resurfacing)

  • 4 sizes

    • Component Sizes and Matching

    AAA Triple A® Ankle replacement

    The AAA Triple A® Total Ankle Replacement is available in

  • 5 sizes for the tibial component
  • 4 sizes for the mobile bearing
  • 4 sizes for the talar component

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    Titanium-Nitride Surface Finish

    AAA Triple A® Ankle replacement

  • Increaserd surface hardness(2.800 HV)

  • Higher scratch resistance

  • Reduced coefficient of friction

  • Better wettability

  • Reduced polyethylene wear

  • Higher protection against corrosion

  • Better compatibility

  • Less metal ion release



    • Titanium Nitride is applied onto the Chromium-Cobalt alloy by physical vapour deposition (PVD). The application of PVD coatings has been in use for 10ths of years in the automotive, aerospace and medical industry.
    The application of Titanium Nitride on Total Ankle Replacements goes back to the 1980's of the last century (6)

    References:


    • (1) Buechel FF, Pappas MJ, Iorio LJ: New Jersey low contact stress total ankle replacement: biomechanical rationale and review of 23 cementless cases. Foot Ankle 8(6):279-290, 1988

    • Raikin SM, Heim CS, Plaxton NA, Greenwald AS: Mobility Characteristics of Total Ankle Replacements" available at The Orthopaedic Reasearch Laboratories homepage: www.orl-inc.com

    • Xuanyong Liu : "Surface Modification of Titanium for Biomedical Application "Mat Science and Engonmeering 2004 Vol 457 pp 49-121

    • Implantcast - The Use of Ceramic Coatings in Orthopaedic Implants (can be downloaded here)

    • Jones VC, Auger DD, Stome MH, Fisher J : "New Materials for Mobile Bearing Knee Prosthesis- Titanium Nitride Counterface Coatings for Reeduction of PolyEthylene Wear" Chapter 21 in Hamelynck KJ " LCS Mobile Bearing Knee Arthroplasty" ISBN-10: 3540432841

    • (Pappas MJ - Makris G- Beughel F : "Titanium Nitride Ceramic Film Against Polyethylene, a 48 million cycle wear test" Clin Orthop Rel Res. 1995 Vol 317 pp 64-71

    • Serro AP et al : "A Comparative Study of TiN TiNbN and TiCn as coatings for Biomedical Applications" - Surface and Coatings 2009 Vol 203 iss 23 pp 3701