Search Results (8)

Background/Objectives: Accurate estimation of intraoperative blood loss in endoscopic spine surgery remains challenging because of continuous saline irrigation and blood infiltration into surrounding soft tissues and potential dead spaces. Hidden blood loss (HBL), resulting from extravasation into tissue compartments or hemolysis, may substantially increase total blood loss (TBL) and contribute to postoperative bleeding-related complications. This study aimed to compare HBL in full-endoscopic unilateral laminotomy with bilateral decompression (FE-ULBD) with that in biportal endoscopic ULBD (BE-ULBD) and open microscopic ULBD (OM-ULBD). Methods: A retrospective analysis was conducted of patients who underwent single-level FE-ULBD, BE-ULBD, or OM-ULBD for lumbar spinal stenosis (LSS) at a single institution. Data on perioperative characteristics, laboratory parameters, perioperative blood loss (TBL, HBL, and visible blood loss), and clinical outcomes were collected and compared. Univariate linear regression analyses were performed to identify factors associated with HBL in the FE-ULBD group. Results: A total of 93 patients were included, comprising 34 in the FE-ULBD group, 32 in the BE-ULBD group, and 27 in the OM-ULBD group. The FE-ULBD group demonstrated significantly lower TBL than both the BE-ULBD and OM-ULBD groups (493.20 ± 183.46 vs. 675.97 ± 192.02 vs. 822.94 ± 424.11 mL, p = 0.001 and p = 0.002, respectively). HBL in the FE-ULBD group was significantly lower than in the BE-ULBD group (390.48 [268.32–506.91] vs. 513.29 [437.96–633.36] mL, p = 0.012) and was numerically lower than in the OM-ULBD group without statistical significance (390.48 [268.32–506.91] vs. 516.38 [316.41–710.68] mL, p = 0.081). Male sex was the only variable significantly associated with increased HBL in the FE-ULBD group. Conclusions: FE-ULBD showed significantly lower TBL than BE-ULBD and OM-ULBD, and lower HBL than BE-ULBD. FE-ULBD may represent a feasible surgical option for single-level LSS, with the potential advantage of reduced perioperative blood loss while maintaining comparable clinical outcomes. Full article

Background/Objectives: Adult degenerative scoliosis (ADS) is a spinal disease causing pain and reduced mobility, often occurring with degenerative lumbar spinal stenosis (DLSS). While fusion stabilizes the spine, it has drawbacks like loss of motion and adjacent segment degeneration. Minimally invasive techniques, such as tubular unilateral laminotomy for bilateral decompression (tULBD), provide a less invasive alternative, but their impact on ADS with DLSS is underexplored. This study examines the short-term effects of navigated tULBD on radiological and clinical outcomes in this patient population. Methods: This retrospective single-center study analyzed patients aged ≥18 years with DLSS and ADS (Cobb angle ≥ 10°), with or without grade I spondylolisthesis, who underwent navigated tULBD between June 2019 and October 2022. Radiological parameters were assessed pre- and post-operatively using AI-powered FXA™ Version 1.33, Raylytic Software GmbH, Leipzig, Germany, while clinical outcomes were evaluated using the Oswestry Disability Index (ODI) and Numeric Rating Scale (NRS) for back and leg pain. Statistical analyses were conducted with R Studio. Results: This study included 20 patients (mean age 74.6 ± 7.6 years, body mass index [BMI] 26.08 ± 3.7 kg/m²), with a median follow-up of 2 months. Most underwent single-level decompression (45%), with a median of 2 surgical levels (IQR: 1–3). Radiological parameters showed no significant changes (p > 0.05). Clinically, the median NRS back improved from 5 (IQR: 3–9) preoperatively to 2 (IQR: 0–2) postoperatively (p = 0.009) and 1 (IQR: 0–4.5) at follow-up (p = 0.004). NRS leg scores dropped from 3.5 (IQR: 0–5) to 0 postoperatively and at follow-up (p = 0.02, p = 0.04). ODI improved from 37.8 (IQR: 29–42.5) preoperatively to 17.5 (IQR: 5–24) at follow-up (p = 0.04). There were no neurological complications. Conclusions: Navigated tULBD is a promising, minimally invasive option for mild ADS and DLSS. It provides significant pain and disability relief without adversely affecting stability and alignment. Long-term studies are needed to confirm durability and efficacy, particularly in severe cases. Full article

Background/Objectives: To evaluate risk factors for postoperative neurological deficits following cervical endoscopic unilateral laminotomy for bilateral decompression (CE-ULBD) and to determine whether intraoperative neurophysiological monitoring (IONM) can predict neurological compromise. Methods: A multicenter retrospective review was performed on 42 CE-ULBD procedures conducted between 2016 and 2024; 33 cases met the inclusion criteria with available imaging and electromyography data. Demographic, operative, and neurophysiological variables were analyzed. Preoperative stenosis severity was graded using the Kang MRI system. Intraoperative IONM data, including electromyography firing and motor evoked potential (MEP) changes, were correlated with new postoperative weakness. Results: The cohort (69.1% male, mean age 70.2 ± 1.7 years, mean BMI 29.6 ± 1.1) included 56 decompressed levels. The most common operative levels were C3-4 (37%) and C4-5 (24%). Postoperative weakness occurred in four patients (12.1%), all of whom had severe (Grade 3) preoperative stenosis. Among these, 50% exhibited preoperative weakness. Neuromonitoring changes correlated significantly with postoperative weakness (Fisher’s Exact, p < 0.001); 100% of patients with new post-operative weakness had sustained MEP decrease at the time of closure. Conclusions: Patients with severe cervical stenosis and preoperative weakness are at heightened risk of postoperative neurological deficits following CE-ULBD. Elevated epidural pressure from continuous irrigation in a constricted canal may exacerbate cord compression, particularly in those with preexisting myelopathy. IONM changes strongly correlate with new deficits and may exacerbate cord compression, particularly in those with preexisting myelopathy, and may serve as an early warning system for impending neurological injury. Surgeons should exercise caution and maintain low irrigation pressures in patients with severe stenosis undergoing endoscopic cervical decompression. Full article

Background/Objectives: Biportal endoscopic spine surgery (BESS) is one of the minimally invasive spine surgery techniques. BESS has several advantages, such as better visualization, less muscle injury, early rehabilitation, etc. Due to its clear visualization, delicate intraoperative hemostasis of the bleeding foci, including cancellous bone and small epidural vessels, can be achieved. Therefore, some authors have reported that BESS resulted in less intraoperative visible blood loss (VBL) compared to conventional open surgery. However, it is difficult to analyze the exact amount of intraoperative blood loss because of the continuous normal saline irrigation. In addition, hidden blood loss (HBL) tends to be overlooked, and the amount of HBL might be larger than expected. We aim to calculate the amount of HBL during BESS and to compare our findings with convention open surgery. Methods: We retrospectively obtained the clinical data of patients that underwent lumbar central decompression from July 2021 to June 2024. Patients were divided into two groups: the BESS group that underwent biportal endoscopic lumbar decompression, and the open surgery group that underwent open decompression. Both groups used unilateral laminotomy and bilateral decompression techniques. Total blood loss (TBL) using preoperative and postoperative change in hematocrit (Hct) was measured using Gross’s formula and the Nadler equation. Since TBL consists of VBL and HBL, HBL was calculated by subtracting the VBL measured intraoperatively from TBL. Results: A total of sixty-six patients in the BESS group and seventeen patients in the open surgery group were included in the study. The TBL was 247.16 ± 346.88 mL in the BESS group and 298.71 ± 256.65 mL in the open surgery group, without significant difference (p = 0.569). The calculated HBL values were 149.44 ± 344.08 mL in the BESS group and 171.42 ± 243.93 mL in the open surgery group. The HBL in the BESS group was lower than the HBL in the open surgery group, without significant difference (p = 0.764). Conclusions: The TBL and HBL during lumbar central decompression were smaller in patients who underwent BESS compared to those who underwent open surgery. While TBL was significantly lower in BESS, HBL did not show statistical significance between the two groups. HBL during BESS should not be neglected, and related hemodynamics should be considered postoperatively. Full article

Cervical endoscopic spine surgery is rapidly evolving and gaining popularity for the treatment of cervical radiculopathy and myelopathy. This approach significantly reduces muscular damage and blood loss by minimizing soft tissue stripping, leading to less postoperative pain and a faster postoperative recovery. As scientific evidence accumulates, the efficacy and safety of cervical endoscopic spine surgery are continually affirmed. Both anterior and posterior endoscopic approaches have surfaced as viable alternative treatments for various cervical spine pathologies. Newer techniques, such as endoscopic-assisted fusion, the anterior transcorporeal approach, and unilateral laminotomy for bilateral decompression, have been developed to enhance clinical outcomes and broaden surgical indications. Despite its advantages, this approach faces challenges, including a steep learning curve, increased radiation exposure for both surgeons and patients, and a relative limitation in addressing multi-level pathologies. However, the future of cervical endoscopic spine surgery is promising, with potential enhancements in clinical outcomes and safety on the horizon. This progress is fueled by integrating advanced imaging and navigation technologies, applying regional anesthesia for improved and facilitated postoperative recovery, and incorporating cutting-edge technologies, such as augmented reality. With these advancements, cervical endoscopic spine surgery is poised to broaden its scope in treating cervical spine pathologies while maintaining the benefits of minimized tissue damage and rapid recovery. Full article

Study Design: Case Series and Technical Note, Objective: UBS has been extensively used in open surgery. However, the use of UBS during UBESS has not been reported in the literature. The aim of this study was to describe a new spinal surgical technique using an ultrasonic bone scalpel (UBS) during unilateral biportal endoscopic spine surgery (UBESS) and to report the preliminary results of this technique. Methods: We enrolled patients diagnosed with lumbar spinal stenosis who underwent single-level UBESS. All patients were followed up for more than 12 months. A unilateral laminotomy was performed after bilateral decompression under endoscopy. We used the UBS system after direct visualization of the target for a bone cut. We evaluated the demographic characteristics, diagnosis, operative time, and estimated blood loss of the patients. Clinical outcomes included the visual analog scale (VAS), the Oswestry Disability Index (ODI), the modified MacNab criteria, and postoperative complications. Results: A total of twenty patients (five males and fifteen females) were enrolled in this study. The mean follow-up period was 13.2 months (range 12–17 months). The VAS score, ODI, and modified MacNab criteria classification improved after the surgery. A minimal mean blood loss of 22.1 mL was noted during the operation. Only one patient experienced neuropraxia, which resolved within 2 weeks. There was no durotomy, iatrogenic pars fracture, or infection. Conclusions: In conclusion, our study represents the first report of the use of UBS during UBESS. Our findings demonstrate that this technique is safe and efficient, with improved clinical outcomes and minimal complications. These preliminary results warrant further investigation through larger clinical studies with longer follow-up periods to confirm the effectiveness of this technique in the treatment of lumbar spinal stenosis. Full article

The clinical and radiological results before and after surgery were compared and analyzed for patients with multilevel lumbar stenosis who underwent bi-portal endoscopic spine surgery (BESS) and microscopic unilateral laminotomy for bilateral decompression (ULBD). We retrospectively identified 47 and 49 patients who underwent BESS and microscopic ULBD, respectively, who were diagnosed with multi-level lumbar stenosis. Clinical outcomes were evaluated using the visual analog scale score for both back and leg pain, and medication (pregabalin) use and Oswestry Disability Index (ODI) scores for overall treatment outcomes were used pre-operatively and at the final follow-up. Radiological outcomes were evaluated as the percentage of dura expansion volume, and percentage preservation of both facets and both lateral recess angles. The follow-up period of patients was about 17.04 months in the BESS group and about 16.90 months in the microscopic ULBD group. The back and leg visual analog scale (VAS) scores and average pregabalin use decreased more significantly in the BESS group than in the microscopic ULBD group (each p-value 0.0443, <0.001, 0.0378). All radiological outcomes were significantly higher in the BESS group than in the ULBD group. The change in ODI in two-level spinal stenosis showed a significantly higher value in the BESS group compared to the microscopic ULBD group (p-value 0.0335). Multilevel decompression with the BESS technique in multiple spinal stenosis is an adequate technique as it shows better clinical and radiological results than microscopic ULBD during a short-term follow-up period. Full article

Objective: There is limited literature on repetitive postoperative MRI and clinical evaluation after Uniportal Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression. Methods: Clinical visual analog scale, Oswestry Disability Index, McNab’s criteria evaluation and MRI evaluation of the axial cut spinal canal area of the upper end plate, mid disc and lower end plate were performed for patients who underwent single-level Uniportal Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression. From the evaluation of the axial cut MRI, four types of patterns of remodeling were identified: type A: continuous expanded spinal canal, type B: restenosis with delayed expansion, type C: progressive expansion and type D: restenosis. Result: A total of 126 patients with single-level Uniportal Lumbar Endoscopic Unilateral Laminotomy for Bilateral Decompression were recruited with a minimum follow-up of 26 months. Thirty-six type A, fifty type B, thirty type C and ten type D patterns of spinal canal remodeling were observed. All four types of patterns of remodeling had statistically significant improvement in VAS at final follow-up compared to the preoperative state with type A (5.59 ± 1.58), B (5.58 ± 1.71), C (5.58 ± 1.71) and D (5.27 ± 1.68), p < 0.05. ODI was significantly improved at final follow-up with type A (49.19 ± 10.51), B (50.00 ± 11.29), C (45.60 ± 10.58) and D (45.60 ± 10.58), p < 0.05. A significant MRI axial cut increment of the spinal canal area was found at the upper endplate at postoperative day one and one year with type A (39.16 ± 22.73; 28.00 ± 42.57) mm², B (47.42 ± 18.77; 42.38 ± 19.29) mm², C (51.45 ± 18.16; 49.49 ± 18.41) mm² and D (49.10 ± 23.05; 38.18 ± 18.94) mm², respectively, p < 0.05. Similar significant increment was found at the mid-disc at postoperative day one, 6 months and one year with type A (55.16 ± 27.51; 37.23 ± 25.88; 44.86 ± 25.73) mm², B (72.83 ± 23.87; 49.79 ± 21.93; 62.94 ± 24.43) mm², C (66.85 ± 34.48; 54.92 ± 30.70; 64.33 ± 31.82) mm² and D (71.65 ± 16.87; 41.55 ± 12.92; 49.83 ± 13.31) mm² and the lower endplate at postoperative day one and one year with type A (49.89 ± 34.50; 41.04 ± 28.56) mm², B (63.63 ± 23.70; 54.72 ± 24.29) mm², C (58.50 ± 24.27; 55.32 ± 22.49) mm² and D (81.43 ± 16.81; 58.40 ± 18.05) mm² at postoperative day one and one year, respectively, p < 0.05. Conclusions: After full endoscopic lumbar decompression, despite achieving sufficient decompression immediately postoperatively, varying severity of asymptomatic restenosis was found in postoperative six months MRI without clinical significance. Further remodeling with a varying degree of increment of the spinal canal area occurs at postoperative one year with overall good clinical outcomes. Full article