Finite element model analysis of lumbar biomechanical characteristics after nucleus discectomy
10.3724/SP.J.1008.2011.00645
- Author:
Hai-Bo LI
1
Author Information
1. Department of Orthopaedics
- Publication Type:Journal Article
- Keywords:
Biomecharfics;
Finite clement analysis;
Lumbar vertebrae;
Nucleus discectomy
- From:
Academic Journal of Second Military Medical University
2011;32(6):645-649
- CountryChina
- Language:Chinese
-
Abstract:
Objective To Use three-dimensional Sinite element model analysis for studying the lijmbar biomechanical characterislics following mjcleijs discectomy in a palierrt with lijmbar iritervertebral disc protrvion. Methods A novel CAD method was adopted to acciirately create the Smite teemerrt modtes of L4/5 segment, mdiidmg the modCls for normal disc, degenerated disc, denucleated disc immediatcly after operaSion (denucleated modCl), and denuCleated disc after a longer lime period (scar growth model) Furthermore, the biomechanical parameters of the foUr modtes were examined under SiVe different loads, riamtey, compresSion, fleXion, extemion, forward and backward shear loads. Resutts (1) Under the iiVe loads, the siiffttess of degerterated modCl was ncreased compared with that of the normal disc under all 5 different loads. (2)The sfiffiiess of dermcleated modCl was decreased than that of degerterated disc and ncreased than that of the normal disc. (3)The siiffness of scar growth modte was enhanced and eVen siripassed that of the degerterated modte due to the fact that the scar tissite filled the irrtradisc caVity. (4) The facet contact force was decreased under CleXion, exteniion, and backward shear loads in dermcleated modCl, and were increased under exteniion, forward and backward shear loads in scar growth modCL (5) The backward budge in the degerterated modte wasobViously siighter than that in the rormal modte. The backward bulge of denucleated modte increased to some ejrterrt, and its inner annulus fibrous had inward bUlging. Conclusion NuCleus discectomy has differerrt effects on the biomecharics of liimbar mofion segment in pafierrts at different iime points after operafion. The impacts on liimbar stabliity and postefiior structure are small immediatery after nuCleus discectomy, and the liimbar moiion segmerT may sfiffen and the stress of ariicular process may ncrease after a longer iime period following nuCleus discectomy.