Vacuum Sealing Drainage for Deep Surgical Site Infection Following Unilateral Biportal Endoscopic Spine Surgery: A Case Report and Literature Review

Abstract Background: Unilateral biportal endoscopy (UBE) features small incisions, relatively limited soft tissue injury and flexible visual field. However, postoperative deep surgical site infection may lead to persistent exudation, paravertebral or intraspinal infection, repeated debridement and prolonged hospitalization. Vacuum sealing drainage (VSD), a form of negative pressure wound therapy (NPWT), has been applied to infected wounds after complex spinal surgery. Nevertheless, dedicated reports on its use for deep infection after UBE remain scarce. Case Summary: An 80-year-old female patient underwent percutaneous unilateral biportal endoscopic lumbar discectomy at L4/5 for lumbar disc herniation with spinal stenosis. High fever occurred on postoperative day 6, with a maximum temperature of 41°C. Laboratory examinations showed procalcitonin (PCT) 0.45 ng/mL, C-reactive protein (CRP) 30.10 mg/L, serum amyloid A (SAA) > 1000.00 mg/L, interleukin-6 (IL-6) 14.30 pg/mL, and erythrocyte sedimentation rate (ESR) 23 mm/h. Contrast-enhanced lumbar MRI revealed marked edema in the left surgical access area at L4/5 and adjacent paravertebral soft tissues, with irregular fluid collection and abnormal enhancement, suggesting postoperative deep soft tissue infection. Enterobacter hormaechei was isolated from drainage fluid. After sufficient debridement and pathogen sampling, continuous VSD at − 125 mmHg was applied. The VSD dressing was replaced twice over 14 days, combined with cefoperazone-sulbactam sodium. After treatment, the incision healed well. Follow-up laboratory tests demonstrated ESR 19 mm/h, white blood cell count 5.13×10⁹/L, and CRP 1.97 mg/L. Follow-up contrast-enhanced lumbar MRI showed marked regression of edema, fluid collection and abnormal enhancement at the L4/5 operative site and surrounding paravertebral soft tissues, indicating substantial improvement. Conclusion: This case suggests that for carefully evaluated deep surgical site infection after UBE, VSD can serve as an adjunct to adequate debridement, reliable pathogen sampling and targeted antimicrobial therapy, providing continuous drainage, dead-space management and wound-bed preparation. A single case cannot confirm that VSD is superior to other drainage or debridement modalities. Further case series and controlled studies are required to clarify its indications, optimal negative-pressure parameters and long-term outcomes.