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. 2024 Aug 13;13(16):4744.
doi: 10.3390/jcm13164744.

Lumbopelvic Stabilization with Two Methods of Triangular Osteosynthesis: A Biomechanical Study

Niklas Grüneweller  1 , Julia Leunig  1   2 , Ivan Zderic  2 , Boyko Gueorguiev  2 , Christian Colcuc  1 , Dirk Wähnert  1 , Thomas Vordemvenne  1
Affiliations

Lumbopelvic Stabilization with Two Methods of Triangular Osteosynthesis: A Biomechanical Study

Niklas Grüneweller et al. J Clin Med. .

Abstract

(1) Background: Pelvic fractures, and particularly instabilities of the dorsal pelvic ring, are becoming increasingly prevalent, particularly in orthogeriatric patients. Spino-pelvic triangular osteosynthesis is an effective approach to achieve sufficient stabilization in vertically unstable fractures. This study compares two types of osteosynthesis: the conventional one and a novel instrumentation where the iliosacral screw is placed through a fenestrated iliac screw. (2) Methods: Sixteen artificial osteoporotic L5+pelvis models with an unstable sacral fracture have been instrumented with either an iliac screw connected with a rod to a L5 pedicle screw and an iliosacral screw (TF) or a fenestrated ilium screw connected with a rod to a L5 pedicle screw and an iliosacral screw passing through the fenestra of the iliac screw (TFS). Biomechanical testing was performed using cyclic loading until failure. (3) Results: Both configurations yielded comparable results with regard to initial stiffness, implant loosening, and cycles to failure. The TFS exhibited markedly higher values for cycles to failure and markedly lower values for loosening. However, due to the characteristics of the artificial bone model, these findings were not significant. (4) Conclusions: The novel triangular fixation systems demonstrated comparable results to the standard triangular osteosynthesis configuration.

Keywords: biomechanics; dorsal pelvic ring; lumbopelvic instability; triangular fixation.

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Conflict of interest statement

N.G., J.L., I.Z., B.G., C.C., and D.W. declare no conflicts of interest. T.V. had the idea for the implant design and holds patent rights and royalties from Silony Medical AG. The funders had no role in the design of the study; in the collection, analyses, or interpretation of the data; in the writing of the manuscript; or in the decision to publish the results.

Figures

Figure 1
Figure 1
Image of the triangular fixation system (TFS) configuration in Group I: a fenestrated iliac screw and an iliosacral screw with a premounted washer stabilize the dorsal pelvic ring. Lumbo-pelvic stabilization is achieved by connecting the polyaxial head adapter of the iliac screw to a pedicle screw rod system.
Figure 2
Figure 2
Image visualizing the configuration of Group II (TF): in contrast to Group I, the iliosacral screw is placed separately from the iliac screw in a more cranial position.
Figure 3
Figure 3
Radiographs in two planes of the triangular fixation system with the sacroiliac screw positioned through the fenestra of the iliac screw.
Figure 4
Figure 4
Radiographs in two planes of the conventional triangular fixation with the sacroiliac screw separate from the iliac screw in a more cranial position.
Figure 5
Figure 5
Setup with a specimen mounted for biomechanical testing. View from anterior (left) and lateral (right). Blue and yellow arrows indicate axial and torsional load applications, respectively.
Figure 6
Figure 6
Sacral screw cutout (a) and screw loosening in iliac bone (b) presented after 2000, 4000, 6000, and 8000 cycles for both groups in terms of mean value and standard deviation.
Figure 7
Figure 7
Cycles to failure for both groups (TFS, TF) presented as mean value and standard deviation.
Figure 8
Figure 8
Catastrophic failure pattern in the TFS group, particularly the failure in the trajectory of the iliac screw.
Figure 9
Figure 9
Catastrophic failure pattern in the TF group, particularly the failure in the trajectory of the iliac screw and the sacroiliac screw.
See this image and copyright information in PMC

References

    1. Audretsch C.K., Siegemund A., Ellmerer A., Herath S.C. Sex Differences in Pelvic Fractures-a Retrospective Analysis of 16 359 Cases from the German Trauma Registry. Dtsch. Arztebl. Int. 2023;120:221–222. doi: 10.3238/arztebl.m2022.0402. - DOI - PMC - PubMed
    1. Rollmann M.F., Herath S.C., Kirchhoff F., Braun B.J., Holstein J.H., Pohlemann T., Menger M.D., Histing T. Pelvic ring fractures in the elderly now and then—A pelvic registry study. Arch. Gerontol. Geriatr. 2017;71:83–88. doi: 10.1016/j.archger.2017.03.007. - DOI - PubMed
    1. Rommens P.M., Hofmann A. The FFP-classification: From eminence to evidence. Injury. 2023;54((Suppl. S3)):S10–S19. doi: 10.1016/j.injury.2021.09.016. - DOI - PubMed
    1. Fuchs T., Rottbeck U., Hofbauer V., Raschke M., Stange R. Beckenringfrakturen im Alter. Der Unfallchirurg. 2011;114:663–670. doi: 10.1007/s00113-011-2020-z. - DOI - PubMed
    1. Riesner H.J., Palm H.G., Friemert B., Lang P., Ag Becken D.G.U. [Triangular minimally invasive spinopelvic stabilization for type C pelvic fractures according to AO/OTA and type IV according to FFP] Der Unfallchirurg. 2021;124:923–930. doi: 10.1007/s00113-020-00952-x. - DOI - PubMed

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