Anatomic Radius
Studies of kinematics and biomechanics have identified a constant radius in natural knee motion centered about the transepicondylar axis.1-3
The Triathlon Knee System is the first of its kind with a patented anatomic radius. Centering the anatomic radius about the transepicondylar axis provides ligament isometry, not only in full extension and 90-degrees of flexion, but through the entire range of motion. Triathlon's anatomic radius is designed to mimic natural knee motion, enhancing stability and mobility in activities such as descending and ascending stairs, gardening, or any similar activity requiring stability at deep flexion angles.
1. Hollister AM, Jatana S, Singh AK, Sullivan WW, Lupichuk AG. The axes of rotation of the knee. Orthopaedic Laboratory, Harbor-UCLA Medical Center, Torrance. Clin Orthop. 1993 May;(290):259-68.
2. Freeman MAR, Pinskerova V, Hill PF, Vedi V,Williams A, Iwaki H, Kadoya Y, Kobayashi A, Nakagawa S, Sakamoto H, Todo S, Yamano Y, Brandsson S, Karrholm J. Tibiofemoral movement – Studies in the cadaveric and living knee using MRI, dissection and RSA; British Editorial Society of Bone and Joint Surgery, 2001.
3. Churchill DL, Incavo SJ, Johnson CC, Beynnon BD. The transepicondylar axis approximates the optimal flexion axis of the knee. Clin Orthop. 1998 Nov;(356):111-8.