Finite element analysis of a novel repair device for lumbar spondylolysis.
- 1Department of Spine Surgery, Mianyang Orthopedic Hospital, Mianyang, Sichuan Province, China.
- 2Department of Preventive Medicine, Sichuan College of Traditional Chinese Medicine, Mianyang, Sichuan Province, China.
- 3Department of Spine Surgery, Mianyang Orthopedic Hospital, Mianyang, Sichuan Province, China. [email protected].
Abstract
Background
This study aimed to compare the biomechanical differences between a novel repair device for lumbar spondylolysis and a nail-hook internal fixation system through three-dimensional finite element analysis.Methods
Three-dimensional images of L4-S1 were constructed based on computed tomography images of a young male patient. Four finite element models were developed: Model A: intact model; Model B: bilateral spondylolysis of the L5 model; Model C: spondylolysis fixed by the nail-hook internal fixation system model; and Model D: spondylolysis fixed by the novel repair device model. A uniformly distributed 600-N vertical downward concentrated force and 10 Nm of torque were applied to the upper surface of the L4 to simulate six physiological activities of the lumbar spine. The fixation effects were evaluated by comparing the range of motion, maximum stress of the intervertebral disks, maximum displacement of the spondylolysis, and stress distribution of the internal fixation.Results
The range of motions of the two internal fixation models were similar in each segment and direction. In terms of the maximum displacement of the spondylolysis, that of the fracture surface in the novel repair device model was significantly reduced compared with the nail-hook internal fixation model in each range of motion. The maximum stress of the intervertebral disks in the two models had their respective advantages in different activity directions, but the difference in stress values was not significant. The stress levels of both internal fixation devices were concentrated on the connecting rod and the junction of the pedicle screw and the connecting rod. Due to the shorter connecting rod of the nail-hook internal fixation system, the stress on the connecting rod was more concentrated, while the stress distribution on the connecting rod of the novel device was more dispersed.Conclusion
The new type of lumbar pars interarticularis repair device is highly reliable in fixation, and the bone grafting area of the pars interarticularis is well exposed, providing favorable conditions for bone grafting and subsequent bone formation. It is a highly promising internal fixation device that offers a new option for pars interarticularis repair.
Related
- Navigation-Assisted Minimally Invasive Direct Pars Repair for Lumbar Spondylolysis
- Effects of Lumbar Lordosis Angle on the Magnitude and Vertebral-Level Distribution of Anterior Cortical Bone Stress in the Lumbar Vertebral Bodies: A Finite Element Analysis.
- Biomechanical Comparison of Unilateral Biportal Endoscopy and Percutaneous Endoscopic Lumbar Discectomy Using a Finite Element Model.
- Bony Union Following Platelet-Rich Plasma and Focused Extracorporeal Shock Wave Therapy for Delayed Union of Bilateral Lumbar Spondylolysis in an Adolescent Gymnast: A Case Report
- Biomechanical comparative analysis of minimally invasive decompression and minimally invasive fusion with internal fixation in the treatment of lumbar spinal stenosis with degenerative spondylolisthesis: a finite element study.
BibTeX
@article{xie2026finite,
title = {{Finite element analysis of a novel repair device for lumbar spondylolysis.}},
author = {Bin Xie and Hongda Xu and Haitao Deng and Mingfan Li and Shengxin Zhao and Youpeng Hu and Li Liu and Peidong Qing},
journal = {BMC musculoskeletal disorders},
year = {2026},
month = aug,
doi = {10.1186/s12891-026-10238-9},
url = {https://europepmc.org/article/MED/42958235},
note = {CC BY},
}
RIS
TY - JOUR
TI - Finite element analysis of a novel repair device for lumbar spondylolysis.
AU - Bin Xie
AU - Hongda Xu
AU - Haitao Deng
AU - Mingfan Li
AU - Shengxin Zhao
AU - Youpeng Hu
AU - Li Liu
AU - Peidong Qing
PY - 2026
DA - 2026/08/03
JO - BMC musculoskeletal disorders
DO - 10.1186/s12891-026-10238-9
UR - https://europepmc.org/article/MED/42958235
AB - Background This study aimed to compare the biomechanical differences between a novel repair device for lumbar spondylolysis and a nail-hook internal fixation system through three-dimensional finite element analysis.Methods Three-dimensional images of L4-S1 were constructed based on computed tomography images of a young male patient. Four finite element models were developed: Model A: intact model; Model B: bilateral spondylolysis of the L5 model; Model C: spondylolysis fixed by the nail-hook internal fixation system model; and Model D: spondylolysis fixed by the novel repair device model. A uniformly distributed 600-N vertical downward concentrated force and 10 Nm of torque were applied to the upper surface of the L4 to simulate six physiological activities of the lumbar spine. The fixation effects were evaluated by comparing the range of motion, maximum stress of the intervertebral disks, maximum displacement of the spondylolysis, and stress distribution of the internal fixation.Results The range of motions of the two internal fixation models were similar in each segment and direction. In terms of the maximum displacement of the spondylolysis, that of the fracture surface in the novel repair device model was significantly reduced compared with the nail-hook internal fixation model in each range of motion. The maximum stress of the intervertebral disks in the two models had their respective advantages in different activity directions, but the difference in stress values was not significant. The stress levels of both internal fixation devices were concentrated on the connecting rod and the junction of the pedicle screw and the connecting rod. Due to the shorter connecting rod of the nail-hook internal fixation system, the stress on the connecting rod was more concentrated, while the stress distribution on the connecting rod of the novel device was more dispersed.Conclusion The new type of lumbar pars interarticularis repair device is highly reliable in fixation, and the bone grafting area of the pars interarticularis is well exposed, providing favorable conditions for bone grafting and subsequent bone formation. It is a highly promising internal fixation device that offers a new option for pars interarticularis repair.
SN - 1471-2474
ER -