Application of Finite Element Analysis in Biomechanical Research of Degenerative Diseases of Lumbar Spine

As the elderly population continues to grow, the number of patients with low back pain is gradually increasing. Among them, Lumbar Degenerative Diseases (LDD) is one of the major contributors to low back pain. Biomechanical in vivo studies of the lumbar spine are mainly performed by implants or imaging data to record the real-time changes of form and stress on the intervertebral disc during motion. However, the current developments are slow due to the technological and ethical limitations. In vitro experiments include animal experiments and cadaver experiments, which are difficult to operate or differ greatly from normal human structures, and the results still need to be verified repeatedly to test their accuracy. As for finite element method, it is relatively low cost and can repeat the experimental results. Therefore, we believe that finite element analysis plays an extremely important role in biomechanical research, especially in analyzing the relationship between different surgical models and the degeneration caused by different mechanics.

Anterior and Posterior Approach Results for Treatment of Cervical Myelopathy in the Elderly: A 10-Year Experience in a Mexican Institution

Introduction: Degeneration of the cervical spine (CDSD) prevalence is nearly 90% by the 7th decade. This is the first research that compares the outcomes between the Anterior Approach (AA) and Posterior Approach (PA) to cervical myelopathy (CM) in the elderly. Materials and Methods: A retrospective observational study of electronic health records at the Hospital Central Sur de Alta Especialidad (HCSAE), PEMEX from January 2010 to May 2020 with patients older than 60 years submitted to cervical surgery. For the analysis we elaborated two groups according to the surgical approach: AA vs PA;we analyzed the trans-operative behavior, the immediate outcome, and after 3 months, 6 months, and 1 year. Results: As a total of 145 patients, the prevalence of CM in elderly was the 63.8% with a median age of 69 (64 - 75) years. We found statistical differences in strength outcome only in the P3m (p = 0.011), for sensitivity we found major prevalence of affection in the PA group. We didn’t report a significant difference in the Neck Disability Index (NDI) at all measures, but the PA presented a major incapacity. The Nurick scale results were significant in all stages (p < 0.05);and presented improvement compared with presurgical period (p < 0.001). Discussion: Patients show significant improvements in outcome measures with either anterior or posterior surgery. Both approaches are highly efficacious in preventing neurologic deterioration and in most cases improve neurological function with appropriate postoperative management like rehabilitation, pain management, and psychological support. Conclusion: The patients submitted to surgical medullary decompression presented a favorable outcome despite the age and the higher prevalence of comorbidities;whereby we favor the surgical treatment in all patients in a case-to-case selection to generate a positive impact on functional outcomes.