Lumbar Facet Joint Kinematics and Load Effects During Dynamic Lifting

et al. 2020

Preprint

Purpose The relationship between facet tropism (FT) and lumbar disc herniation (LDH) is not clear. In the present study, MRI was used to assess the relationship between lumbar facet joint tropism and disc herniation. This paper is the first to assess the relationship between facet joint tropism and LDH from the sagittal view. Methods 122 patients (154 segments) with lumbar disc herniation and 102 normal subjects (306 segments) who visited our hospital from 01-Jan-2020 to 01-Apr-2020 were included in this study. The axial and sagittal angles of facet joints were measured using an MRI scan. The difference of 10° in facet angles between left and right was defined as lumbar facet tropism. The relationship between the two was analyzed. Results In the axial, 95/154 segments with lumbar disc herniation had FT whereas, 48/258 segments had FT in the normal segments(p < 0.01). In the sagittal, 61/154 segments with lumbar disc herniation had FT and 48/306 had FT in the control(p < 0.01). Conclusion The proportion of FT is better in patients with lumbar disc herniation, and there is a significant correlation between FT and lumbar disc herniation.

Section: Discussionmentioning

confidence: 99%

Correlation between facet tropism and lumbar disc herniation

Han

Wang

et al. 2020

Preprint

“…The value of comfort can be viewed as an evaluation reference of labor intensity. Yang Feng describes the astronaut’s discomfort level by the relative relationship between the torque used by the joint and the maximum available torque of the joint [ 6 ], which is defined as the ratio of the actual torque tau and the maximum force moment max of the joints, like the followings

…”

Section: Methodsmentioning

confidence: 99%

“…The most common form of low back pain is nonspecific, affecting almost all age groups [ 5 ]. However, in different occupational backgrounds, workers’ repeated bending of the spine, frequent heavy lifting, manual material handling and awkward body postures are still important factors that cause MSDs of the waist [ 6 ]. Back compressive force on the spine is believed to be a contributor to low-back pain and injury, especially at the L5/S1 intervertebral disc [ 7 ].…”

Section: Introductionmentioning

confidence: 99%

“…Among these methods, the biomechanical load analysis is objective and relatively precise without subjective evaluation bias and angle errors which are common in video capture systems. In recent decades, researchers developed biomechanical models to quantify spinal load during manual materials’ lifting, including static models based on the postures analysis [ 15 ], dynamic models considering movements [ 6 ], cumulative spinal load (CSL) calculation and 3D biomechanical models involve twisting. An early study refined the static sagittal-plane (SSP) biomechanical model conducted by Morris [ 16 ], which simplified the human body as a series of seven links and computed corresponding forces and torques during simulated manual materials carrying tasks [ 17 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

A Biomechanical Waist Comfort Model for Manual Material Lifting

et al. 2020

IJERPH

Low back pain (LBP) is a common disorder that affects the working population worldwide. LBP causes more disability than any other conditions all around the world. Most existing studies focus on the occupational physical factors in association with LBP, while few focus on individual factors, especially the lack of quantitative calculation of waist comfort in biomechanics. Based on the physical statistics of Chinese men, this research used human posture analysis (HPA) to establish the waist strength formula and analyzed the waist strength during a manual material handling. It also explored the influence of weight and height of lifting objects on the L5-S1 spinal load. On this basis, a waist comfort model was proposed in combination with the recommended weight limit (RWL) recommended by NIOSH, and the parameter selection and waist comfort value were verified by Jack simulation software. The results show that pulling force of the Erector Spinae of the waist is closely related to the weight and lifting height of the object. Parameter verification and Jack software simulation results show that the force of L5-S1 is less than 3400 N, which proves that the waist force under this posture is acceptable. The developed waist comfort model can be applied to evaluate work risk, to adjust working intensity and powered exoskeleton design, aiming to decrease the prevalence of LBP.

“…This causes lumbar facet joint osteoarthritis and Lumbar facet joint arthropathy are also believed to be the primary etiology in 15%-20% of patients with chronic low back pain [8,10,17]. Some other researches established that lifting contributes the most to the risk of low back pain [5].…”

Section: Introductionmentioning

confidence: 99%

The Effect of Various Weight-bearing Activity on the Motion of the Lumbar Facet Joints in Vivo

Wen

et al. 2021

Preprint

Background: Lumbar facet joints (LFJ) are usually related to the pathogenesis of the spine, but the quantification of normal FJ motion is still limited to in vitro studies, animal models, and imaging analysis. Few people report the in vivo kinematics of facet joints. There has always been a debate about whether it can induce biomechanical changes in the motion pattern of the facet joints after weight-bearing, resulting in the degeneration of the facet joints and osteoarthritis.Methods: A total of 10 healthy volunteers, 5 males , and 5 females, aged 21≤39 years, with an average age of 32±5 years, were recruited. Using the combination of DFIS and CT, the sagittal images of L3-S1 segments scanned by CT were transformed into three-dimensional reconstruction models and then matched to the instantaneous images of lumbar spine motion taken by a double fluorescent X-ray system under different loads. To reproduce the instantaneous motion state of lumbar vertebrae in different positions (supine position, standing position, flexion-extension position, left-right bending, left-right rotation) under different loads(0kg,10kg), assisted by computer-related software, in vivo human LFJ 6-DOF kinematics were obtained.Result: In flexion and extension exercises: there is no statistical difference in the horizontal rotation angle (α, β, r) of each segment after weight-bearing. The coupling translations are significantly reduced in the left and right direction of the L34 segment (P<0.05). In the L45 segment, the articular process was significantly reduced in the anteroposterior direction (left P<0.05). In lateral bending: the main rotation axis rotation range was different after weight-bearing, L45 decreased (P=0.023), and L5S1 decreased significantly (P=0.021), there is no difference in the coupling rotation range, the coupling translations only decreases in the left and right direction of the L34 segment (P<0.05); in the rotation movement: the horizontal rotation angle of each segment after the load (α, β, r) There was no statistical difference. The coupling translation was only in the L5/S1 segment and decreased in the craniocaudal direction (P<0.05). In the three movements, the asymmetric movement of the left and right articular processes occurred in the L34 segment (P<0.05), and the maximum translations after weight-bearing were found at L5/S1.Conclusion: Increased weight-bearing will affect the motion pattern of lumbar facet joints. The asymmetric movement of the left and right sides of the L34 segment is related to the asymmetry of the facet. The increase in translation of L5/S1 after weight-bearing compared with other segments may be related to the anatomical structure of the facet joint morphology deviated to the coronal position and frontal plane. Through the analysis of the body motion data of the lumbar facet joints before and after the weight-bearing, the relationship with the lumbar spine-related diseases is obtained. And it can provide a reference for guiding healthy lifestyles, clinical surgical procedures, and new spinal implants.