Background: It is generally believed that lumbar disc herniation is more common in the elderly population. But with the continuous change of life and working style, more and more young people are suffering from lumbar disc herniation due to their long hours at the desk and poor posture. Purpuse: To analyze the characteristics of lumbar lordosis (LL), intervertebral angle (IVA) and lumbosacral angle (LSA) in young patients with low back pain and their relationship with lumbar disc herniation. Material and Methods: 148 young patients with low back pain underwent lumbar magnetic resonance (MR) and digital radiography (DR). According to the results, they were divided into non-lumbar disc herniation group (NLDH group) and lumbar disc herniation group (LDH group). LL, IVA and LSA were measured on the lateral plainradiographs. Then we compare and analyze the characteristics of LL, IVA and LSA of the two groups and their relationship with lumbar disc herniation. Results: In both groups, IVA gradually increased from L1-L2 to L5-S1, and it reached the maximum at L5-S1. IVA of each segment and the mean LL in LDH group were both smaller than those in NLDH group, but the mean LSA was larger in LDH group, and the differences were all statistically significant (P<0.05). Lumbar disc herniation was negatively correlated with IVA from L1-L2 to L5-S1 and LL, but positively correlated with LSA. Young patients with lower LL and IVA and higher LSA are more likely to develop lumbar disc herniation. Conclusion: LL, IVA and LSA measured on the lateral plain radiographs can be used as important reference indexes to reflect the condition of lumbar disc herniation.

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For the problem that some parameters in system dynamics model are difficult to quantify, cloud model, which has the excellent characteristic of qualitative and quantitative transformation, is used in the determination of parameters of system dynamics model. Firstly, the system dynamics model revealing interactive development between the logistics industrial clusters and urbanisation is proposed. Secondly, the specific procedures of parameters calibration based on cloud model are given. Finally, a case study based on Shenyang economic zone is employed to verify the proposed model. According to the simulation results, some best suggestions on interactive development between logistics industrial clusters and urbanisation are put forward.

Objectives This study aimed to evaluate the clinical efficacy and safety of percutaneous endoscopic interlaminar discectomy (PEID) for treating highly downward-migrated disc herniation. Methods We conducted a retrospective study on 39 patients with highly downward-migrated disc herniation who underwent PEID treatment between January 2015 and October 2020. The clinical outcomes, including the preoperative and postoperative visual analogue scale (VAS) for the back and leg, Oswestry Disability Index (ODI), and MacNab criteria for surgical success, were evaluated and compared to thirty-seven patients treated with posterior lumbar interbody fusion (PLIF). Results The mean operation time of PEID was 93.00(77.00,110.00) min, while that of PLIF was 169.00(157.00,183.00) min. Continued improvement in both PEID and PLIF was observed in the VAS and ODI scores immediately after the surgery to the last follow‐up. The VAS and ODI scores of PEID one week after surgery were significantly different from those of PLIF. One patient with recurrent lumbar disc herniation in the same segment improved after undergoing repeat PEID, two patients had dura tears, and conservative treatment helped relieve the symptoms. The overall percentage of patients with good to excellent results of PELD according to the modified MacNab criteria was 97.43%, while that of PLIF was 94.60%. Conclusions PEID has reliable efficacy and safety for treating highly downward-migrated disc herniation. And the long-term efficacy of PEID is comparable to PLIF. No severe complications occurred after surgery, and most patients’ symptoms were relieved.

BackgroundLumbar disc herniation (LDH) linked with posterior ring apophysis separation (PRAS) is a rare and distinct subset of disc herniation. Few studies have evaluated the clinical efficacy of percutaneous endoscopic lumbar discectomy (PELD), which is a procedure used to treat LDH linked with PRAS.ObjectivesTo evaluate the clinical efficacy and safety of PELD in the treatment of LDH linked with PRAS.MethodsPatients who met inclusion criteria (n = 67; 40 males and 27 females) underwent PELD. General and operation-related information and perioperative complications of the patients were recorded. Clinical efficacy was measured using the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) during the follow-up period.ResultsThe mean operation time was 118.04 ± 19.31 min and the mean blood loss was 22.84 ± 15.89 ml. The VAS and ODI scores continued to improve immediately after the surgery to the last follow-up. Four patients experienced postoperative complications i.e., herniation recurrences. The conditions of the patients with the complications improved after treatment.ConclusionsPELD has reliable efficacy and safety in the treatment of LDH linked with PRAS.