An interventional study of Unilateral Biportal Endoscopic Surgery in Lumbar Disc Herniation, Lumbar Spinal Stenosis and Lumbar Degenerative Disease, sponsored by Fan Zhang. Recruiting at 1 site in China. Open to participants aged 18 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-09-23.
Sponsored by Fan Zhang · Not applicable, Interventional, and Treatment
This study is being done to find out if the height of the fluid bag and the direction of the surgical cut affect the pressure of the fluid used during unilateral biportal endoscopic (UBE) spine surgery. UBE is a minimally invasive surgery for the spine. During this surgery, fluid is used to keep the surgical area clear and to control bleeding. The pressure of this fluid may affect how clear the surgical view is, how much bleeding occurs, and how well patients recover after surgery. We will also collect disc tissue removed during surgery to study how disc degeneration is related to factors such as sex, age, mechanical stress, and injury. About 80 patients aged 18 to 75 who are scheduled for UBE surgery at our hospital will take part. Patients will be randomly assigned to one of four groups based on two things: the height of the fluid bag (0.9 meters or 1.0 meters) and the direction of the surgical cut (horizontal or vertical). We will measure the fluid pressure around the spinal covering during surgery and record how clear the surgical view is. After surgery, we will track patients' pain and recovery for at least 6 months. This study has been approved by the hospital ethics committee.
Background: Unilateral biportal endoscopy (UBE) is a minimally invasive spine surgery technique that has been increasingly used for lumbar disc herniation, spinal stenosis, and other degenerative conditions. Irrigation fluid is essential in UBE to maintain the surgical space and control bleeding. However, the pressure of irrigation fluid may be associated with complications such as neck pain, seizures, and increased intracranial pressure. The height of the fluid bag and the direction of the surgical incision are two controllable factors that may influence actual irrigation pressure and surgical field clarity, but prospective clinical evidence is lacking.
Objective: This study aims to investigate the effects of different fluid bag heights (0.9 m vs. 1.0 m) and incision directions (horizontal vs. vertical) on irrigation pressure, surgical field clarity, blood loss, and early postoperative pain and functional recovery in patients undergoing UBE surgery. Additionally, disc tissue collected during surgery will be used to explore the relationship between disc degeneration and factors such as sex, age, mechanical stress, and injury.
Design: This is a single-center, prospective, randomized controlled trial. Approximately 80 patients scheduled for UBE surgery at the First Affiliated Hospital of Kunming Medical University will be enrolled. Patients will be randomly assigned to one of four groups: (1) 0.9 m fluid bag height + horizontal incision; (2) 0.9 m fluid bag height + vertical incision; (3) 1.0 m fluid bag height + horizontal incision; (4) 1.0 m fluid bag height + vertical incision. Intraoperative irrigation pressure around the dura will be continuously measured. Surgical field clarity, blood loss, and early postoperative outcomes will be recorded. Patients will be followed for at least 6 months.
474 studies on the registry are indexed under Intervertebral Disc Displacement; 100 are open to participants now.
This study's planned enrollment of 80 is above the median of 63 across 344 interventional studies indexed under Intervertebral Disc Displacement.
Browse Intervertebral Disc Displacement studies →This is the only study on the registry with Fan Zhang as lead sponsor.
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
UBE surgery with 0.9 m fluid bag height and transverse incision.
Procedure: Unilateral Biportal Endoscopic Surgery
UBE surgery with 0.9 m fluid bag height and longitudinal incision.
Procedure: Unilateral Biportal Endoscopic Surgery
UBE surgery with 1.0 m fluid bag height and transverse incision.
Procedure: Unilateral Biportal Endoscopic Surgery
UBE surgery with 1.0 m fluid bag height and longitudinal incision.
Procedure: Unilateral Biportal Endoscopic Surgery
UBE surgery performed with specified fluid bag height (0.9 m or 1.0 m) and incision direction (transverse or longitudinal).
Irrigation pressure around the dura
Intraoperative irrigation pressure around the dura measured continuously during UBE surgery.
Time frame: During surgery
Plan to share: No — Individual participant data will not be shared because the study involves a small sample of patients from a single center, and the data contain sensitive personal and surgical information. Protecting participant privacy and complying with local ethics regulations are the primary reasons for not sharing the data.
No publications or documents are linked to this record.
Started Feb 2026 (actual). Primary completion is estimated for Dec 2027, 22 months after the start.
Of 178 non-industry interventional studies with no phase under Intervertebral Disc Displacement, half reached primary completion within 11 months of starting (the median), counting those still running; a quarter within 5 and three quarters within 23. This study's planned 22 months is above that.
Counting every sponsor, half of 191 studies reached it within 12 months; a quarter within 5 and three quarters within 27.
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Intervertebral Disc Displacement →