Objective To evaluate early postoperative mobility after lumbar decompression using real-time location system (RTLS)-derived objective metrics and to explore differences in mobility patterns between biportal endoscopic decompression and open decompression.
Methods This retrospective cohort study included 323 patients who underwent lumbar decompression for degenerative lumbar spinal stenosis between March 2020 and May 2024. RTLS sensors embedded in wristbands continuously recorded patient mobility during postoperative days (PODs) 1–4. Primary RTLS-derived outcomes included total walking distance, mean walking speed, and active movement ratios (top 20% and top 50%). Between-group comparisons were performed using nonparametric tests. Propensity score matching and multivariable median quantile regression adjusting for age, American Society of Anesthesiologists physical status, and preoperative mobility were conducted.
Results RTLS identified differences in early postoperative activity patterns between surgical approaches. In adjusted analyses, activity-intensity–based metrics, particularly the top 20% activity ratio, remained significantly higher in the biportal endoscopic decompression group across multiple PODs. Subgroup analyses demonstrated minimal differences after single-level decompression, whereas activity-based differences were more frequently observed in multilevel procedures.
Conclusion RTLS-based continuous monitoring detected differences in early postoperative activity patterns following lumbar decompression. These findings support the role of RTLS as an objective tool for assessing early functional recovery in spine surgery.
Objective Unilateral biportal endoscopic (UBE) spine surgery is a minimally invasive technique that uses continuous irrigation to improve visualization and control bleeding. Effective water pressure management is crucial for patient safety, particularly at the cervical and thoracic levels where spinal cord injury risk is higher. However, real-time pressure monitoring remains underexplored. This study evaluates the impact of real-time water pressure monitoring on safety during UBE surgery.
Methods A prospective study was conducted involving 20 patients undergoing UBE lumbar spine surgery. Patients were divided into 2 groups based on the irrigation system: gravity-based or infusion pump. Real-time water pressure was monitored using a digital sensor throughout surgery. Each procedure was categorized into 3 phases: phase I, working space preparation; phase II, laminectomy; phase III, flavectomy, dura exposure, and discectomy. Data was analyzed according to the type of irrigation system and surgical phase.
Results The mean water pressure in the surgical field during UBE spine surgery was 17.98± 8.07 mmHg, with no significant differences between surgical phases. However, the infusion pump system maintained significantly lower mean pressure (12.10±3.51 mmHg) compared to the gravity-based system (23.86±6.97 mmHg, p=0.001). The infusion pump system consistently maintained a significantly lower mean water pressure compared to the gravity-based system.
Conclusion Real-time water pressure monitoring during UBE surgery enhances safety by enabling improved control of pressure within the surgical field. Both the gravity-based and infusion pump systems safely maintained working space pressure, with the pump system showing significantly lower pressure levels.
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Case Report: Spinal epidural lipomatosis with incomplete cauda equina syndrome treated with unilateral biportal endoscopic technique Zaiyin Deng, Yujin Wang, Mohammed Saud Shaik, Duanyang Li, Rongjing Di, Zhourui Wu, Bin Ma Frontiers in Surgery.2026;[Epub] CrossRef
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Sang-Min Park, Kwang-Sup Song, Dae-Woong Ham, Ho-Joong Kim, Min-Seok Kang, Ki-Han You, Choon Keun Park, Dong-Keun Lee, Jin-Sung Kim, Hong-Jae Lee, Hyun-Jin Park
Neurospine 2024;21(4):1190-1198. Published online December 31, 2024
Objective To compare the safety profiles of biportal endoscopic spinal surgery (BESS) and microscopic spinal surgery (MSS) for lumbar disc herniation and spinal stenosis by analyzing the associated adverse events.
Methods We pooled data from 2 prospective randomized controlled trials involving 220 patients (110 in each group) who underwent single-level lumbar surgery. Participants aged 20–80 years with radiating pain due to lumbar disc herniation or spinal stenosis were included in this study. Adverse events were recorded and analyzed over a 12-month follow-up period.
Results The overall adverse event rates were 9.1% (10 of 110) in the BESS group and 17.3% (19 of 110) in the MSS group, which were not statistically significantly different (p=0.133). Notably, wound dehiscence occurred in 8.2% of MSS cases but in none of the BESS cases. Both groups showed similarly low rates of complications, such as dural tears, epidural hematoma, and nerve root injury. The most common adverse event in the BESS group was recurrent disc herniation (2.7%), whereas that in the MSS group was wound dehiscence (8.2%).
Conclusion BESS demonstrated a safety profile comparable to that of MSS for the treatment of lumbar disc herniation and spinal stenosis, with a trend towards fewer overall complications. BESS offers particular advantages in terms of reducing wound-related complications. These findings suggest that BESS is a safe alternative to conventional MSS and potentially offers the benefits of a minimally invasive approach without compromising patient safety.
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