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

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.

Best practice in radiofrequency denervation of the lumbar facet joints: a consensus technique

Background: Radiofrequency denervation is used to treat selected people with low back pain. Recent trials have been criticised for using a sub-optimal intervention technique. Objectives: To achieve consensus on a best practice technique for administering radiofrequency denervation of the lumbar facet joints to selected people with low back pain. Study design: A consensus of expert professionals in the area of radiofrequency denervation of the lumbar facet joints. Methods: We invited a clinical member from the 30 most active UK departments in radiofrequency pain procedures and two overseas clinicians with specific expertise to a 1 day consensus meeting. Drawing on the known anatomy of the medial branch, the theoretical basis of radiofrequency procedures, a survey of current practice and collective expertise, delegates were facilitated to reach consensus on the best practice technique. Results: The day was attended by 24 UK and international clinical experts. Attendees agreed a best practice technique for the conduct of radiofrequency denervation of the lumbar facet joints. Limitations: This consensus was based on a 1 day meeting of 24 clinical experts who attended and took part in the discussions. The agreed technique has not been subject to input from a wider community of experts. Conclusions: Current best practice for radiofrequency denervation has been agreed for use in a UK trial. Group members intend immediate implementation in their respective trusts. We propose using this in a planned Randomised Controlled Trial (RCT) of radiofrequency denervation for selected people with low back pain.

Open Endoscopic Rhizotomy

The etiology of axial low back pain is multifactorial and includes pain arising from lumbar facet joints. The facet joints, capsules, and surrounding tissues are innervated by the medial branches of the dorsal rami. Rhizotomy of these nerves can provide pain relief in patients with lumbar facetogenic pain. The reported benefits of endoscopic approaches to the spine include minimal disruption of nonpathologic anatomy while simultaneously allowing for improved visualization of pathologic anatomy. Endoscopic techniques have been described for spinal stenosis, disc herniation, interbody fusion, infection, as well as dorsal medial branch rhizotomy. The goal of medial branch rhizotomy is to denervate lumbar facet joints that are contributing to axial back pain. The previous chapter focused on percutaneous techniques, while this chapter will describe endoscopic rhizotomy.

Lumbar Facet Joint Kinematics and Load Effects During Dynamic Lifting

Objective: To examine the lumbar facet joint kinematics in vivo during dynamic lifting and the effects of the load lifted. Background: Although extensive efforts have been dedicated to investigating the risk factors of low back pain (LBP) associated with load handling in the workplace, the biomechanics of lumbar facet joints during such activities is not well understood. Method: Fourteen healthy participants performed a load-lifting task while a dynamic stereo-radiography system captured their lumbar motion continuously. Data from 11 participants were included for subsequent analysis. A randomized block design was employed to study the load effect (4.5 kg, 9.0 kg, and 13.5 kg) on bilateral facet joint motions at approximately 60°, 40°, 20°, and 0° trunk-flexion postures. The facet orientations were also examined. Results: Significant load effects were found for the flexion and lateral bending and superior-inferior translation of the facet joints. The L5-S1 displayed greater lateral bending and twisting, which was due to its more posterolateral orientation than the L2-L3, L3-L4, and L4-L5 facet joints. The left-right asymmetry in facet orientation was observed, most prominently at L3-L4 and L5-S1 facet joints. Conclusion: The lumbar facet joint kinematics are affected by the magnitude of the lifted load and are dependent on the orientations of articulating adjacent facets. Application: This study provided new insights into the role of lumbar facet joints in vivo during lifting. Alterations in the facet joint kinematics due to vigorous functional demand can be one of the primary but overlooked mechanical factors in the causation of LBP.

RELATIONSHIP BETWEEN PARAMETERS OF THE LUMBAR FACET JOINTS IN A LONG-TERM POSTOPERATIVE OUTCOME

ABSTRACT Objective: To analyze the impact of the relationship between tropism and angulation of the lower lumbar facet joints on a remote clinical outcome after dynamic and rigid surgical interventions. Methods: Patients with degenerative diseases of the lower lumbar spine were subdivided into three groups, according to the method of surgical treatment: 1) (n=48) the use of an artificial prosthesis intervertebral disc (IVD); 2) (n=42) the use of interbody fusion combined with transpedicular and transfacet stabilization; 3) (n=51) the use of interbody fusion and bilateral transpedicular stabilization. Analysis was performed of the remote clinical parameters and neuroimaging characteristics before the operation was performed. Results: When analyzing clinical and instrumental parameters, a significant correlation was found between the long-term outcomes of surgical treatment on the VAS and Oswestry scales and the neuroimaging data on angulation and tropism of the facet joints (FJ). Conclusions: The data obtained testify to the importance of preoperative diagnosis of tropism and angulation of the lower lumbar facet joint, which enables differentiated surgical tactics to be selected, and remote clinical outcomes to be optimized. In the presence of neuroimaging parameters of Facet Joint angulation of less than 600, regardless of the presence of tropism, it is possible to perform total arthroplasty of IVD. When neuroimaging parameters of Facet Joint angulation of more than 600 are detected, rigid stabilization of the operated segment is recommended, while in the absence of tropism of Facet Joints, a contralateral transfacetal fixation is possible; in the presence of tropism, it is expedient to perform bilateral transpedicular stabilization. Level of Evidence II; Prognostic Studies—Investigating the Effect of a Patient Characteristic on the Outcome of Disease.