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Biomechanical evaluation of different semi-rigid junctional fixation techniques using finite element analysis
Julia L van Agtmaal1, Remco J P Doodkorte2, Alex K Roth2
1Orthopaedic Biomechanics, Department of Biomedical Engineering, Eindhoven University of Technology, Den Dolech 2, 5612AZ Eindhoven, the Netherlands; Department of Orthopaedic Surgery, Research School CAPHRI, Maastricht University Medical Center, P. Debyelaan 25, 6229HX Maastricht, the Netherlands.
Clinical Biomechanics (Bristol, Avon)
|August 19, 2023
Summary
Semi-rigid spinal fixation techniques may reduce proximal junctional failure by decreasing stress. Different methods show varied effects on ligament forces and disc stress, requiring clinical trials for validation.
Area of Science:
- Spine biomechanics
- Orthopedic surgery
- Finite element analysis
Background:
- Proximal junctional failure (PJF) is a common complication of rigid spinal instrumentation for adult spinal deformity.
- Semi-rigid fixation aims to reduce junctional stresses by creating a gradual range of motion transition.
- This study evaluates biomechanical effects of semi-rigid junctional fixation techniques.
Purpose of the Study:
- To investigate the biomechanical impact of various semi-rigid junctional fixation techniques.
- To compare these techniques against traditional pedicle screw fixation.
- To assess their potential in mitigating proximal junctional failure.
Main Methods:
- A T8-L3 finite element spine model was developed.
- Intervertebral disc degeneration was simulated.
- Semi-rigid techniques (hooks, clamped tapes, knotted tapes) were modeled proximally to pedicle screw fixation.
- Posterior ligament complex forces and nucleus pulposus stresses were quantified.
Main Results:
- All tested semi-rigid techniques reduced posterior ligament complex forces compared to pedicle screw fixation.
- Transverse process hooks and knotted tapes decreased nucleus pulposus stresses.
- Clamped tapes, however, increased nucleus pulposus stresses at the junctional zone.
Conclusions:
- The biomechanical effects of semi-rigid fixation are complex and technique-dependent.
- Further clinical investigation is necessary to determine the efficacy of these methods in reducing proximal junctional failure rates.
Keywords:
Adult spinal deformityFinite element modellingProximal junctional kyphosisSpine biomechanicsMore Related Videos
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