Implant Material and Design Alter Construct Stiffness in Distal Femur Locking Plate Fixation: A Pilot Study
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Construct stiffness affects healing of bones fixed with locking plates. However, variable construct stiffness reported in the literature may be attributable to differing test configurations and direct comparisons may clarify these differences.
We therefore asked whether different distal femur locking plate systems and constructs will lead to different (1) axial and rotational stiffness and (2) fatigue under cyclic loading.
We investigated four plate systems for distal femur fixation (AxSOS, LCP, PERI-LOC, POLYAX) of differing designs and materials using bone substitutes in a distal femur fracture model (OTA/AO 33-A3). We created six constructs of each of the four plating systems. Stiffness under static and cyclic loading and fatigue under cyclic loading were measured.
Mean construct stiffness under axial loading was highest for AxSOS (100.8 N/mm) followed by PERI-LOC (80.8 N/mm) and LCP (62.6 N/mm). POLYAX construct stiffness testing showed the lowest stiffness (51.7 N/mm) with 50% stiffness of AxSOS construct testing. Mean construct stiffness under torsional loading was similar in the group of AxSOS and PERI-LOC (3.40 Nm/degree versus 3.15 Nm/degree) and in the group of LCP and POLYAX (2.63 Nm/degree versus 2.56 Nm/degree). The fourth load level of > 75,000 cycles was reached by three of six AxSOS, three of six POLYAX, and two of six PERI-LOC constructs. All others including all LCP constructs failed earlier.
Implant design and material of new-generation distal femur locking plate systems leads to a wide range of differences in construct stiffness.
Assuming construct stiffness affects fracture healing, these data may influence surgical decision-making in choosing an implant system.
- Augat P, Burger J, Schorlemmer S, Henke T, Peraus M, Claes L. Shear movement at the fracture site delays healing in a diaphyseal fracture model. J Orthop Res. 2003;21:1011–1017. CrossRef
- Augat P, Simon U, Liedert A, Claes L. Mechanics and mechano-biology of fracture healing in normal and osteoporotic bone. Osteoporos Int. 2005;16(Suppl 2):S36–43. CrossRef
- Bottlang M, Doomink J, Lujan TJ, Fitzpatrick DC, Marsh JL, Augat P, von Rechenberg B, Lesser M, Madey SM. Effects of construct stiffness on healing of fractures stabilized with locking plates. J Bone Joint Surg Am. 2010;92(Suppl 2):12–22. CrossRef
- Bottlang M, Lesser M, Koerber J, Doornink J, von Rechenberg B, Augat P, Fitzpatrick DC, Madey SM, Marsh JL. Far cortical locking can improve healing of fractures stabilized with locking plates. J Bone Joint Surg Am. 2010;92:1652–1660. CrossRef
- Doornink J, Fitzpatrick DC, Madey SM, Bottlang M. Far cortical locking enables fixation with periarticular locking plates. J Orthop Trauma. 2011;25:S29–34. CrossRef
- Duda GN, Schneider E, Chao EY. Internal forces and moments in the femur during walking. J Biomech. 1997;30:933–941. CrossRef
- Gaebler C, Speitling A, Milne EL, Stanzl-Tschegg S, Vécsei V, Latta LL. A new modular testing system for biomechanical evaluation of tibial intramedullary fixation devices. Injury. 2001;32:708–712. CrossRef
- Haidukewych G, Sems SA, Huebner D, Horwitz D, Levy B. Results of polyaxial locked-plate fixation of periarticular fractures of the knee. J Bone Joint Surg Am. 2007;89:614–620. CrossRef
- Henderson CE, Lujan T, Bottlang M, Fitzpatrick DC, Madey SM, Marsh JL. Stabilization of distal femur fractures with intramedullary nails and locking plates: differences in callus formation. Iowa Orthop J. 2010;30:61–68.
- Henderson CE, Lujan TJ, Kuhl LL, Bottlang M, Fitzpatrick DC, Marsh JL. 2010 Mid-America Orthopaedic Association Physician in training award: healing complications are common after locked plating for distal femur fractures. Clin Orthop Relat Res. 2011;469:1757–1765. CrossRef
- Higgins TF, Pittman G, Hines J, Bachus KN. Biomechanical analysis of distal femur fracture fixation: fixed-angle screw-plate construct versus condylar blade plate. J Orthop Trauma. 2007;21:4–6.
- Kregor PJ, Stannard JA, Zlowodski M, Cole PA. Treatment of distal femur fractures using the less invasive stabilization system: surgical experience and clinical results in 103 fractures. J Orthop Trauma. 2004;18:509–520. CrossRef
- Lujan TJ, Henderson CE, Madey SM, Fitzpatrick DC, Marsh JL, Bottlang M. Locked plating of distal femur fractures leads to inconsistent and asymmetric callus formation. J Orthop Trauma. 2010;24:156–162. CrossRef
- Marti A, Fankhauser C, Frenk A, Cordey J, Gasser B. Biomechanical evaluation of the less invasive stabilization system for the internal fixation of distal femur fractures. J Orthop Trauma. 2001;15:482–487. CrossRef
- Mueller ME, Nazarian S, Koch P, Schatzker J. The Comprehensive Classification of Fractures of Long Bones. Berlin, Germany: Springer Verlag; 1990:120–121. CrossRef
- Otto RJ, Moed BR, Bledsoe JG. Biomechanical comparison of polyaxial-type locking plates and fixed-angle locking plates for internal fixation of distal femur fractures. J Orthop Trauma. 2009;23:645–652. CrossRef
- Taylor SJG, Walker PS. Forces and moments telemetered from two distal femoral replacements during various activities. J Biomech. 2001;34:839–848. CrossRef
- Taylor SJG, Walker PS, Perry JS, Cannon SR, Woledge R. The forces in the distal femur and the knee during walking and other activities measured by telemetry. J Arthroplasty. 1998;13:428–437. CrossRef
- Wähnert D, Hoffmeier K, Froeber R, Hofmann GO, Mueckley T. Distal femur fractures of the elderly—different treatment options in a biomechanical comparison. Injury. 2011;42:655–659. CrossRef
- Wähnert D, Hoffmeier KL, von Oldenburg G, Froeber R, Hofmann GO, Mueckley T. Internal fixation of type-C distal femoral fractures in osteoporotic bone. J Bone Joint Surg Am. 2010;92:1442–1452. CrossRef
- Weckbach S, Losacco JT, Hahnhaussen J, Gebhard F, Stahel PF. Challenging the dogma on inferiority of stainless steel implants for fracture fixation. An end of the controversy? Unfallchirurg. 2012;115:79–79. CrossRef
- Weight M, Collinge C. Early results of the less invasive stabilization system for mechanically unstable fractures of the distal femur (AO/OTA types A2, A3, C2 and C3). J Orthop Trauma. 2004;18:503–508. CrossRef
- Wilkens KJ, Curtiss S, Lee MA. Polyaxial locking plate fixation in distal femur fractures: a biomechanical comparison. J Orthop Trauma. 2008,22:624–628. CrossRef
- Zlowodzki M, Williams S, Zardiackas LD, Kregor PJ. Biomechanical evaluation of the less invasive stabilization system and the 95 degree angled blade plate for the internal fixation of distal femur fractures in human cadaveric bones with high mineral density. J Trauma. 2006;60:836–840. CrossRef
- Zlodowski M, Williamson S, Cole PA, Zardiackas LD, Kregor PJ. Biomechanical evaluation of the less invasive stabilisation system, angled blade plate, and retrograde intramedullary nail for the internal fixation of distal femur fractures. J Orthop Trauma. 2004;18:494–502. CrossRef
- Implant Material and Design Alter Construct Stiffness in Distal Femur Locking Plate Fixation: A Pilot Study
Clinical Orthopaedics and Related Research®
Volume 471, Issue 9 , pp 2808-2814
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- 1. Department of Trauma Orthopaedic Surgery, Krankenhaus der Barmherzigen Schwestern Ried, Schlossberg 1, 4910, Ried im Innkreis, Austria
- 2. Institute of Biomechanics, Trauma Center Murnau, Murnau, Germany
- 3. Department of Material Science, Regensburg University of Applied Sciences, Regensburg, Germany
- 4. Institute of Biomechanics, Paracelsus Medical University Salzburg, Salzburg, Austria