Biomechanical comparison of lumbar spine with or without spina bifida occulta. A finite element analysis

Abstract

Study design: Biomechanical study using finite element model (FEM) of lumbar spine. Objectives: Very high coincidence of spina bifida occulta (SBO) has been reported more than in 60% of lumbar spondylolysis. The altered biomechanics due to SBO is one considerable factor for this coincidence. Thus, in this study, the biomechanical changes in the lumbar spine due to the presence of SBO were evaluated. Setting: United States of America (USA). Methods: An experimentally validated three-dimensional nonlinear FEM of the intact ligamentous L3-S1 segment was used and modified to simulate two kinds of SBO at L5. One model had SBO with no change in the length of the spinous process and the other had a small dysplastic spinous process. Von Mises stresses at pars interarticularis were analyzed in the six degrees of lumbar motion with 400 N axial compression, which simulates the standing position. The range of motion at L4/5 and L5/S1 were also calculated. Results: It was observed that the stresses in all the models were similar, and there was no change in the highest stress value when compared to the intact model. The range of motion was also similar in all the models. The lumbar kinematics of SBO was thus shown to be similar to the intact model. Conclusion: SBO does not alter lumbar biomechanics with respect to stress and range of motion. The high coincidence of spondylolysis in spines with SBO may not be due to the mechanical factors.

Chiropractic Care of Acute Low Back Pain and Incidental Spina Bifida Occulta: A Case Report

“…14 Lumbar range of motion with SBO may have the same movement patterns as an intact lumbar spine, although this does not take into consideration activities of daily living of the individuals. 6 As previously stated, SBO can possibly lead to degenerative changes in the future and should be considered when developing a treatment plan for a patient with lower back pain.…”

“…With around 20% of the population having SBO, chiropractic physicians are very likely to encounter this incidental finding in their practices. 6,7 Anomalies within the spine are not uncommon, but are sometimes overlooked due to their benign presentation. 6 Few studies examine the utilization of HVLA in patients with SBO and lower back pain.…”

“…6,7 Anomalies within the spine are not uncommon, but are sometimes overlooked due to their benign presentation. 6 Few studies examine the utilization of HVLA in patients with SBO and lower back pain. This report demonstrates the viability of HVLA once neurological signs and symptoms such as motor or sensory loss are ruled out in the management of an adolescent with lower back pain and SBO at the fifth lumbar vertebrae.…”

“…[3][4][5] According to clinical studies, around 20% of the population may have SBO. 6,7 It usually is www.journalchiromed.com present at the levels of the 5th lumbar and 1st sacral vertebra. 6,8,9 Spina bifida occulta in most cases is asymptomatic, but symptoms among the population may include back pain, enuresis, motor or sensory dysfunction, and posterior disc herniation.…”

“…6,7 It usually is www.journalchiromed.com present at the levels of the 5th lumbar and 1st sacral vertebra. 6,8,9 Spina bifida occulta in most cases is asymptomatic, but symptoms among the population may include back pain, enuresis, motor or sensory dysfunction, and posterior disc herniation. 7,9,10 Fusion of vertebral lamina forms the spinous process, and this process serves as attachment sites for many extensor muscles.…”