EXPRESS: Serum miR-145-5p as a Predictive Biomarker for Postoperative Pain after Percutaneous Kyphoplasty

BACKGROUND: Thoracolumbar compression fractures are common in older adults. Percutaneous kyphoplasty (PKP) is a standard minimally invasive treatment, but 30% to 50% of patients still have persistent or inadequate pain relief after the procedure. OBJECTIVE: To investigate the predictive value and mechanism of serum microRNA-145-5p (miR-145-5p) in PKP-related postoperative pain and to support precise pain assessment and intervention. METHOD: Ninety-five patients with thoracolumbar compression fractures treated with PKP were divided into a low pain group (49 cases, VAS 0-3) and a high pain group (46 cases, VAS 4-10) based on one-month postoperative VAS scores. Fasting venous blood was collected preoperatively and one month postoperatively. Serum miR-145-5p and erythroblastic oncogene B4 (ErbB4) levels were measured by qPCR. An LPS-induced inflammatory model was established in RSC96 cells, and their target relationship and effects on inflammation were assessed via cell transfection, enzyme-linked immunosorbent assay (ELISA), and a dual-luciferase reporter gene assay. Logistic regression identified influencing factors, and ROC analysis evaluated the predictive value of miR-145-5p. RESULTS: The high pain group had higher preoperative VAS, lower bone density T-values, lower miR-145-5p and higher ErbB4. miR-145-5p targeted ErbB4's 3'UTR, inhibiting inflammation by regulating ErbB4. Preoperative VAS, bone density T-value, and miR-145-5p were independent predictors of moderate-to-severe postoperative pain. Preoperative miR-145-5p had predictive value. CONCLUSION: Preoperative serum miR-145-5p is a potential biomarker for assessing PKP-related postoperative pain, aiding precise intervention.