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Objective: Oblique lateral locking plate system (OLLPS) with the locking and reverse pedicle track screw configuration is a novel internal fixation designed for oblique lumbar interbody fusion(OLIF). It is placed in a single-position through the oblique lateral surgical corridor to reduce operative time and subsequent complications of prolonged anesthesia and prone positioning. The purpose of this study was to verify the biomechanical effect of OLLPS.Methods: The intact finite element model of L1–S1（Intact） was established based on CT images of a healthy male volunteer. The L4-L5 intervertebral space was selected as the surgical segment. The surgical models were established separately according to the OLIF surgical procedures and the different internal fixations: (1) stand-alone OLIF (SA); (2) OLIF with 2-screw lateral plate (LP-2); (3) OLIF with 4-screw lateral plate (LP-4); (4) OLIF with OLLPS (OLLPS); and (5) OLIF with bilateral pedicle screw fixation (BPS). After validating the intact model, the physiological loading was applied to the superior surface of L1 to simulate flexion, extension, left bending, right bending, left rotation, and right rotation motions. The evaluation indexes included the L4/5 range of motion (ROM), the L4 maximum displacement, and the maximum stress of the superior and inferior endplate, cage, and supplemental fixation.Results: In OLIF surgery, OLLPS provided multiplanar stability which was similar to that of BPS. Compared with LP-2 and LP-4, OLLPS had the better biomechanical properties in enhancing the instant stability of the surgical segment, reducing the stress of the superior and inferior endplates of the surgical segment, and reducing the risk of cage subsidence.Conclsions: With the minimally invasive background, OLLPS can be an alternative to BPS in OLIF and has a better prospect of clinical promotion and application.

Abstract-The Conducted Electromagnetic Interference (CEI) characteristics in the primary circuit and at the ports of the secondary devices of the converter station of a UHVDC transmission system are researched comprehensively and systematically in this paper, by taking the Zhalute-Qingzhou ±800 kV/10000 MW UHVDC project in East Inner Mongolia of China as an example. The primary circuit equipment parameters of the target system are designed systematically at first, and the overall broadband equivalent model of the main circuit of the UHVDC system, which is composed of converter valve, converter transformer, filter banks and smoothing reactor, is developed. The CEI characteristics in the primary circuit under various conditions of the UHVDC system are analyzed based on the simulations carried out on the built BEC, and the influences of several primary circuit elements on the propagation of the CEI characteristics are researched. To improve the accuracy of the analysis of the CEI characteristics in the secondary device circuit, accurate BECs of the Capacitor Voltage Transformer (CVT), Current Transformer (CT) and secondary signal cable are established. The CEI characteristics at the ports of secondary devices under different operation modes are studied, and the influences of the cable length and burden rate on the CEI characteristics are analyzed. This paper provides a comprehensive and thorough understanding of the CEI characteristics of an UHVDC system.