A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright posture

Background: A quantitative relationship between increasing upper body weight and both 1) non-instrumented lumbosacral joint loading and 2) fusion instrumentation reactions is established using a three-dimensional (3D) finite element model (FEM) of the human thoracolumbosacral spine. Methods: A 3D FE...

Full description

Bibliographic Details
Main Authors: Justin M Warren, MS, PhD, Lloyd A Hey, MD, MS, Andre P Mazzoleni, PhD
Format: Article
Language:English
Published: Elsevier 2021-12-01
Series:Biomedical Engineering Advances
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2667099221000232
_version_ 1798026670634958848
author Justin M Warren, MS, PhD
Lloyd A Hey, MD, MS
Andre P Mazzoleni, PhD
author_facet Justin M Warren, MS, PhD
Lloyd A Hey, MD, MS
Andre P Mazzoleni, PhD
author_sort Justin M Warren, MS, PhD
collection DOAJ
description Background: A quantitative relationship between increasing upper body weight and both 1) non-instrumented lumbosacral joint loading and 2) fusion instrumentation reactions is established using a three-dimensional (3D) finite element model (FEM) of the human thoracolumbosacral spine. Methods: A 3D FEM of the thoracolumbosacral spine (both non-instrumented and instrumented with fusion instrumentation) is developed and validated against cadaveric spine specimens. Upper body weight loading is applied to simulate an individual with varying levels of body mass index (BMI) including 25 kg/m2, 30 kg/m2, 35 kg/m2, and 40 kg/m2. Maximum force/moment joint reactions from L1–S1 in the non-instrumented model are recorded. Maximum instrumentation reactions in the fusion model are recorded. Findings: With BMI of 25 kg/m2 as a reference, nearly all joints experience amplified percent increases in joint loading compared to percent weight gain for each level of obesity studied. Considering spinal fusion instrumentation, rod stresses and pedicle screw reactions likewise experience amplified loading increases compared to body weight. Compressive force at L5–S1 increases by 47%, 86%, and 132% for total body weight increases of 20%, 40%, and 60%, respectively. Fusion rod stresses increase by 47%, 86%, and 128% for the same body weight increases. Interpretations: This paper quantitatively illustrates the importance of nutrition and weight control as part of a comprehensive approach to low back pain management and treatment. Increases in loading on the joints in the lumbosacral spine and in fusion instrumentation are amplified when compared to the corresponding increases in body weight for various clinical levels of obesity. These results illustrate that moderate weight loss can produce significant lower back and spine benefits.
first_indexed 2024-04-11T18:38:54Z
format Article
id doaj.art-b5558a720307492ba2c4cc8ada247b1e
institution Directory Open Access Journal
issn 2667-0992
language English
last_indexed 2024-04-11T18:38:54Z
publishDate 2021-12-01
publisher Elsevier
record_format Article
series Biomedical Engineering Advances
spelling doaj.art-b5558a720307492ba2c4cc8ada247b1e2022-12-22T04:09:04ZengElsevierBiomedical Engineering Advances2667-09922021-12-012100023A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright postureJustin M Warren, MS, PhD0Lloyd A Hey, MD, MS1Andre P Mazzoleni, PhD2Department of Mechanical and Aerospace Engineering, North Carolina State University, 3242 Engineering Building III, 911 Oval Drive, Campus Box 7910, Raleigh, NC 27695-7910 United StatesHey Clinic for Scoliosis and Spine Care, 3320 Wake Forest Rd Suite 450, Raleigh, NC 27609 United StatesDepartment of Mechanical and Aerospace Engineering, North Carolina State University, 3242 Engineering Building III, 911 Oval Drive, Campus Box 7910, Raleigh, NC 27695-7910 United States; Corresponding author.Background: A quantitative relationship between increasing upper body weight and both 1) non-instrumented lumbosacral joint loading and 2) fusion instrumentation reactions is established using a three-dimensional (3D) finite element model (FEM) of the human thoracolumbosacral spine. Methods: A 3D FEM of the thoracolumbosacral spine (both non-instrumented and instrumented with fusion instrumentation) is developed and validated against cadaveric spine specimens. Upper body weight loading is applied to simulate an individual with varying levels of body mass index (BMI) including 25 kg/m2, 30 kg/m2, 35 kg/m2, and 40 kg/m2. Maximum force/moment joint reactions from L1–S1 in the non-instrumented model are recorded. Maximum instrumentation reactions in the fusion model are recorded. Findings: With BMI of 25 kg/m2 as a reference, nearly all joints experience amplified percent increases in joint loading compared to percent weight gain for each level of obesity studied. Considering spinal fusion instrumentation, rod stresses and pedicle screw reactions likewise experience amplified loading increases compared to body weight. Compressive force at L5–S1 increases by 47%, 86%, and 132% for total body weight increases of 20%, 40%, and 60%, respectively. Fusion rod stresses increase by 47%, 86%, and 128% for the same body weight increases. Interpretations: This paper quantitatively illustrates the importance of nutrition and weight control as part of a comprehensive approach to low back pain management and treatment. Increases in loading on the joints in the lumbosacral spine and in fusion instrumentation are amplified when compared to the corresponding increases in body weight for various clinical levels of obesity. These results illustrate that moderate weight loss can produce significant lower back and spine benefits.http://www.sciencedirect.com/science/article/pii/S2667099221000232ObesityOverweightFinite Element MethodFusionLow Back Pain
spellingShingle Justin M Warren, MS, PhD
Lloyd A Hey, MD, MS
Andre P Mazzoleni, PhD
A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright posture
Biomedical Engineering Advances
Obesity
Overweight
Finite Element Method
Fusion
Low Back Pain
title A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright posture
title_full A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright posture
title_fullStr A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright posture
title_full_unstemmed A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright posture
title_short A finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine, and fusion instrumentation, in a standing upright posture
title_sort finite element study of the relationship between upper body weight and the loads experienced by the human lumbosacral spine and fusion instrumentation in a standing upright posture
topic Obesity
Overweight
Finite Element Method
Fusion
Low Back Pain
url http://www.sciencedirect.com/science/article/pii/S2667099221000232
work_keys_str_mv AT justinmwarrenmsphd afiniteelementstudyoftherelationshipbetweenupperbodyweightandtheloadsexperiencedbythehumanlumbosacralspineandfusioninstrumentationinastandinguprightposture
AT lloydaheymdms afiniteelementstudyoftherelationshipbetweenupperbodyweightandtheloadsexperiencedbythehumanlumbosacralspineandfusioninstrumentationinastandinguprightposture
AT andrepmazzoleniphd afiniteelementstudyoftherelationshipbetweenupperbodyweightandtheloadsexperiencedbythehumanlumbosacralspineandfusioninstrumentationinastandinguprightposture
AT justinmwarrenmsphd finiteelementstudyoftherelationshipbetweenupperbodyweightandtheloadsexperiencedbythehumanlumbosacralspineandfusioninstrumentationinastandinguprightposture
AT lloydaheymdms finiteelementstudyoftherelationshipbetweenupperbodyweightandtheloadsexperiencedbythehumanlumbosacralspineandfusioninstrumentationinastandinguprightposture
AT andrepmazzoleniphd finiteelementstudyoftherelationshipbetweenupperbodyweightandtheloadsexperiencedbythehumanlumbosacralspineandfusioninstrumentationinastandinguprightposture