Background: Compared with open lumbar microdiscectomy, percutaneous endoscopic lumbar discectomy (PELD) has the advantages of remarkable preservation of paravertebral structures, less bleeding, shorter operation time and fewer complications, it is a common method for the treatment of lumbar disc herniation (LDH). Local anesthesia is recommended during PELD. However, intraoperative pain is sometimes difficult to control satisfactorily. The efficacy of bilateral intervertebral foramen block (IFB) for pain management in PELD remains unclear. Therefore, this regimen is utilized in a randomized controlled trial for the assessment the safety and effectiveness of bilateral IFB for PELD pain control. Method: This is a single center and randomized controlled trial which will be implemented from September 2020 to September 2021. This research protocol is in accordance with the items of the Standard Protocol for Randomized Trials, which was authorized through the Ethics Committee of Huzhou Central Hospital & Affiliated Centre Hospital of Huzhou University (HZCH0465-0864). 100 participants who undergo PELD will be analyzed. Inclusion criteria contains patients diagnosed with LDH undergoing PELD; people between the ages of 18 and 75; consistent imaging evidence of herniation at a same level (CT or MRI); receive conservative treatment for 2 months. The exclusion criteria contains: patients with the history of severe renal and hepatic dysfunction; more than 1 responsible level LDH combined with other spinal diseases needing advanced surgical treatment (such as fracture, spondylolisthesis, lumbar spinal stenosis, tumor, etc.); Patients have mental illness that will prevent their willingness to participate in the study. Patients will be randomly divided into bilateral IFB group (with 50 patients) and local infiltration analgesia group (with 50 patients). Primary outcomes are pain score at different time points. The secondary outcomes are the operative time, radiation exposure time, length of hospital stay and postoperative complications. All the analysis is implemented through applying the IBM SPSS Statistics for Windows, version 20 (IBM Corp., Armonk, NY, USA). Results: The clinical outcome variables between groups are illustrated in the Table 1. Conclusion: This investigation can offer a reliable basis for the effectiveness and safety of IFB in treating the PELD pain. Trial registration: This study protocol is registered in Research Registry (researchregistry5985).

The incidence of cancer is increasing worldwide on a yearly basis, with the number of patients with bone metastases also increasing annually. Events associated with bone metastases can seriously affect patient quality of life, through pain, hypercalcemia, bone marrow regeneration disorders, and spinal cord compression. In this nonrandomized controlled clinical trial study, we focused on the relationship between bone metastasis, pain, and cytokines before and after radiotherapy. We hypothesized that radiotherapy alters the cytokine profile of the local bone environment. Combined with the analgesic effects of radiotherapy, certain cytokines may be very sensitive to radiation. External radiation therapy is commonly used to treat cancer patients with bone metastases and can effectively relieve metastasis-related pain, although its underlying mechanisms have not been fully elucidated. For this case-control study, we recruited 30 cancer patients with bone metastasis and 30 healthy individuals. Peripheral venous blood from healthy individuals was collected. The clinical characteristics and peripheral venous blood were collected from patients one week before and one week after radiotherapy. The preradiotherapy and postradiotherapy pain scores, quality of life (QOL), and blood cytokine profiles of the patients to that of the controls were collected to identify pain-related cytokines. Finally, the pain score and the quality of life score improved significantly after radiotherapy. Moreover, the preradiotherapy and postradiotherapy blood cytokine profiles of the patients showed significant differences, indicating that the analgesic effect of radiotherapy against bone metastases is mediated via altered cytokine production. Furthermore, some cytokines were more sensitive to radiotherapy. The levels of MIP-1δ, MCP-2, TIMP-1, RANTES, IGFBP3, and TNF-α showed significant differences in the pairwise comparative analysis and may therefore mediate pain associated with bone metastasis.