Artikel
Augmented LISS plating is biomechanically advantageous over conventional LISS plating
Suche in Medline nach
Autoren
-
Boyko Gueorguiev
- AO Research Institute Davos, Davos, Switzerland
-
Dimitar Todorov
- AO Research Institute Davos, Davos, Switzerland
-
Ivan Zderic
- AO Research Institute Davos, Davos, Switzerland
-
Karl Stoffel
- Universität Basel, Kantonsspital Baselland, Basel, Switzerland
-
Mark Lenz
- Friedrich Schiller Universität, Universitätsklinikum Jena, Klinik für Unfall-, Hand- und Wiederherstellungschirurgie, Jena, Germany
-
Geoff Richards
- AO Research Institute Davos, Davos, Switzerland
-
Dian Enchev
- University Hospital for Emergency Medicine 'N. I. Pirogov', Sofia, Bulgaria
| Veröffentlicht: | 23. Oktober 2017 |
|---|
Gliederung
Text
Objectives: Distal femoral fractures in the geriatric population are with increasing incidence and represent the second most common insufficiency fractures of the femur following those around the hip joint. Fixation in osteoporotic bone and early mobilisation in feeble and polymorbide patients is challenging. Development of a fixation approach for augmentation of conventional LISS plating may result in superior long-term clinical outcomes and enhance safe weight bearing.
The aim of this study was to investigate the biomechanical competence of two different techniques of augmented LISS plating for treatment of osteoporotic fractures of the distal femur in comparison to conventional LISS plating.
Methods: Unstable distal femoral fracture AO/OTA 33-A3 was set in artificial femora with low density simulating osteoporotic bone. Three study groups of 10 specimens each were created for instrumentation with a 9-hole LISS plate, a LISS plate with an additional 3D-printed polyactide cylindrical intramedullary graft, and a LISS plate plus a medial 3.5mm LCP (double plating).
All specimens were non-destructively tested under axial (20-150N) and torsional (0-4Nm) quasi-static loading (Abbildung 1 [Fig. 1]).
Each construct was tested with two different working length (WL) configurations (long and short) of the LISS plate. Relative movements between the most medial superior and inferior osteotomy aspects were investigated via motion tracking analysis.
Results and Conclusion: Interfragmentary displacement along the femur axis (mm) under 150N axial loading was 2.03±0.23/1.65±0.27 for LISS with long/short WL, 0.18±0.06/0.18±0.04 for double plating with long/short WL, and 0.40±0.05/0.30±0.05 for LISS plus graft with long/short WL. Shear interfragmentary displacement (mm) under 4Nm torsional loading in internal rotation was 1.16±0.17/0.92±0.11 for LISS with long/short WL, 0.40±0.10/0.43±0.07 for double plating with long/short WL, and 1.09±0.13/0.82±0.11 for LISS plus graft with long/short WL. Double plating revealed significantly smaller longitudinal and shear displacement than the other two techniques for long and short WL, respectively (P ≤ 0.010). In addition, LISS plus graft fixation was with significantly less longitudinal displacement in comparison to conventional LISS plating for long and short WL, respectively (P ≤ 0.001). Long WL resulted in significantly higher longitudinal and shear displacement compared to short WL for LISS and LISS plus graft (P ≤ 0.032), but not for double plating (P=1.000).
Intramedullary grafting resulted in significantly increased fracture stability under axial loading in comparison to conventional LISS plating. However, it was not efficient enough to achieve comparable stability to double plating.
