A 30-Year Worldwide Research Productivity of Scientific Publication in Full-Endoscopic Decompression Spine Surgery: Quantitative and Qualitative Analysis.

OBJECTIVE: The ever-growing number of articles related to full-endoscopic spine surgery published in the last few decades presents a challenge which is perplexing and time-consuming in identifying the current research status. The study aims to identify and analyze the most cited works related to full-endoscopic decompression spine surgery, compare the articles published by different publishers and area, and show the current publication status of full-endoscopic research. METHODS: Using Bibliometrix, CiteSpace, and VOSviewer, we analyzed the bibliometric data selected from the Web of Science database between 1992 and 2022. Spine has the highest H-index with the most-cited journal in the field of full-endoscopic decompression spine surgery. China ranked as the most productive country, whereas the most cited with high H-index papers came from South Korea. For the author analysis, Yeung AT, Ruetten S, Hoogland T, Ahn Y, Choi G, and Mayer HM were the most impactful authors in the global and local citations. The most productive organization is Wooridul Spine Hospital. CONCLUSION: The bibliometric study showed a growing trend of research on full-endoscopic decompression spine surgery over the past 30 years. It has demonstrated that there is a significant increase in the number of authors, institutions, and internationally collaborated countries. However, the quality of studies is still low, and the lack of high-quality clinical evidence and the trend of general journal submissions has somewhat affected the quality of endoscopy journals in recent years.

Changes in Temperature Following Radiofrequency Thermal Ablation of the Nucleus Pulposus and Annulus Fibrosus: A Cadaveric Study.

BACKGROUND: Various minimally invasive procedures for treating discogenic pain have been reported in recent years. A Disc-FX® system can be used to perform nucleus pulposus (NP) removal, radiofrequency ablation, and annuloplasty under the guidance of x-ray fluoroscopy. However, when a probe tip with focused heat is placed on the intradiscal/subannular area to perform nucleo-annuloplasty using radiofrequency lesioning, thermal injury to the spinal cord or spinal nerves is a concern. OBJECTIVES: To assess the thermal profile generated by the Disc-FX ablation and modulation system in intervertebral discs from human cadaveric spine sections and evaluate the safety of its thermal dispersion function. STUDY DESIGN: A cadaveric study. METHODS: NP ablation and annulus fibrosus modulation were performed on a fresh human cadaveric lumbar spine intervertebral disc in a 36.5°C circulating water bath using radiofrequency. The 4 points from the center of the disc to one-third, two-thirds and the outer layer of the annulus were divided into 4 points, A-D, respectively, and radiofrequency lesions were performed on the 4 points. RESULTS: The temperature was increased upon irradiation. It fell slowly with the cessation of irradiation. The temperature was not significantly different between Turbo and Hemo mode at each point. The temperature was not significantly different among the 4 points at each mode. The average temperature of the ventral side of the dura mater was kept below 37°C. LIMITATIONS: The results of this study are limited due to the use of a cadaveric spine, which could not reflect the effect of soft tissue such as muscles and connective tissue around the disc. The position of the temperature measuring probe was relatively fixed. This cadaver demonstration was conducted at the L4-L5 level, which is mostly not restricted by the height of the iliac crest.  CONCLUSIONS: When performing NP ablation and annular modification, the epidural peripheral temperature should always be kept below 37°C. This preliminary in vitro research using human cadaveric discs showed that radiofrequency maintained the epidural space at a safe temperature during nucleo-annuloplasty.

Allogeneic blood transfusions and infection risk in lumbar spine surgery: An American College of Surgeons National Surgery Quality Improvement Program Study.

BACKGROUND: Allogenic blood transfusions can lead to immunomodulation. Our purpose was to investigate whether perioperative transfusions were associated with postoperative infections and any other adverse events (AEs), after adjusting for potential confounding factors, following common elective lumbar spinal surgery procedures. STUDY DESIGN AND METHODS: We performed a multivariate, propensity-score matched, regression-adjusted retrospective analysis of the American College of Surgeons National Surgical Quality Improvement Program database between 2012 and 2016. All lumbar spinal surgery procedures were identified (n = 174,891). A transfusion group (perioperative transfusion within 72 h before, during, or after principal surgery; n = 1992) and a control group (no transfusion; n = 1992) were formed. Following adjustment for between-group baseline features, adjusted odds ratios (aOR) and 95% confidence intervals (95% CI) were calculated using a multivariate logistic regression model for any surgical site infection (SSI), superficial SSI, deep SSI, wound dehiscence, pneumonia, urinary tract infection, sepsis, any infection, mortality, and any AEs. RESULTS: Transfusion was associated with an increased risk of each specific infection, mortality, and any AEs. Statistically significant between-group differences were demonstrated with respect to any SSI (aOR: 1.48; 95% CI: 1.01-2.16), deep SSI (aOR: 1.66; 95% CI: 0.98-2.85), sepsis (aOR: 2.69; 95% CI: 1.43-5.03), wound dehiscence (aOR: 2.27; 95% CI: 0.86-6.01), any infection (aOR: 1.46; 95% CI: 1.13-1.88), any AEs (aOR: 1.80; 95% CI: 1.48-2.18), and mortality (aOR: 2.17; 95% CI: 0.77-6.36). CONCLUSION: We showed an association between transfusion and infection in lumbar spine surgery after adjustment for various applicable covariates. Sepsis had the highest association with transfusion. Our results reinforce a growing trend toward minimizing perioperative transfusions, which may lead to reduced infections following lumbar spine surgery.

Hybrid Interlaminar Endoscopic Lumbar Decompression in Disc Herniation Combined With Spinal Stenosis.

BACKGROUND: Endoscopic spine surgery is an alternative to the traditional treatment of lumbar disc herniation. However, the traditional technique of interlaminar endoscopic approach is challenging and risky in patients with concomitant spinal stenosis. OBJECTIVE: To report a modified technique called hybrid interlaminar endoscopic lumbar decompression as an effective treatment. METHODS: Patients with combined lumbar disc herniation and lateral recess stenosis undergoing full-endoscopic interlaminar lumbar discectomy were retrospectively studied. The hybrid interlaminar endoscopic discectomy technique, as well as the use of 2 endoscopes with different diameters, is described in detail. The large endoscope is used for the laminotomy procedure, while the small endoscope is used for the discectomy procedure. The demographics and clinical outcomes of the patients are presented. RESULTS: A total of 19 patients were included in this study. The mean age was 46.7 yr. The visual analog scale for back and leg pain improved from 5.6 ± 3.4 and 7.5 ± 2.3 to 1.8 ± 1.3 and 1.8 ± 1.6, respectively (P < .001). The mean Oswestry Disability Index improved from 59.9 ± 21.2 preoperatively to 18.2 ± 8.5 postoperatively (P < .001). The follow-up was 8.2 mo on average. No major complications occurred, but 2 patients reported mild postoperative paresthesia. One patient had an early recurrence and underwent repeat endoscopic discectomy. CONCLUSION: Full-endoscopic lumbar discectomy provides excellent access to the intracanalicular herniation site of an intervertebral disc. By using the endoscopic technique presented here, surgeons can safely and efficiently achieve adequate decompression in patients with lumbar disc herniation combined with spinal stenosis.

The evolution of interlaminar endoscopic spine surgery.

Due to the aging population, patients required spinal surgery for degenerative spondylopathy is increasing. With the advent of surgical instruments and techniques, minimally invasive spine surgery is prevalent worldwide. Besides microscopic techniques, endoscopic spine surgery has gotten attention gradually in this surgical field for the past two decades. There are two essential approaches developed currently, including transforaminal and interlaminar approach. These innovative equipment and skills promote the progression of endoscopic surgery from discectomy to decompression of spinal stenosis. Meanwhile, they also opened up the application of endoscopic surgery in a complicated situation. From the perspective of emerging technologies and techniques, the authors will review the evolution and describe the prospects of the interlaminar endoscopic spine surgery (IESS).

Biportal Endoscopic Excision of Facetal Cyst in the Far Lateral Region of L5S1: 2-Dimensional Operative Video.

Unilateral biportal endoscopy (UBE) is a recently introduced technique that utilizes 2 portals, one for endoscopy and one as a working portal, in contrast to full endoscopy, which utilizes a single portal. The advantages are a favorable learning curve and free mobility of instruments in the operative field. UBE is successful in addressing cervical and lumbar disc herniations, lumbar stenosis, and foraminal/extraforaminal pathologies, such as herniations and foraminal stenosis. However, there is no report of UBE for a far-lateral L5S1 facet cyst. The patient was an 85-yr-old female with a left lower limb radicular pain with magnetic resonance imaging evidence of the facet cyst compressing the L5 nerve root. Conventional treatment of such a condition would either be an L5S1 fusion procedure or a standalone decompression via the Wiltse paramedian approach. Because the patient had no instability, we decided to do a standalone decompression using the UBE technique. The UBE technique has the advantages of any minimal access procedure, including small incisions, minimal tissue dissection, good magnification, and preservation of anatomic structures. A written informed consent was obtained from the patient before the procedure. The procedure was done under general anesthesia using a 30° endoscope, a radiofrequency probe, and standard lumbar spine surgery instruments. The initial landing point of the endoscope and instruments is via triangulation at the lateral border of the isthmus of L5. The postoperative clinical and radiological outcomes were satisfactory (VAS Back and Leg, 0; Oswestry disability index, 15 at 3 mo).

Radiographic and clinical outcomes of huge lumbar disc herniations treated by transforaminal endoscopic discectomy.

OBJECTIVES: Large Central disc herniations (occupying more than 50% of canal area) are notorious as they are generally associated with worse outcomes and are technically difficult to manage. Transforaminal endoscopy (TELD) has evolved to become an interesting alternative for lumbar disc herniations. The aim of the paper is to review our technique of transforaminal endoscopy in large central disc herniations and describe the clinical and radiographic results. We also describe an innovative technique of intraoperative epidurography to assess the adequacy of decompression in some cases with severe canal compromise. PATIENTS AND METHODS: We performed a retrospective analysis of all the patients undergoing TELD from December 2012 to October 2018 for huge central lumbar disc herniations. The procedure was done under local anaesthesia and required a more horizontal approach angle, undercutting of superior articular process and posterior annular release to reach the herniated fragment in the epidural space. In severe cases, a radiopaque dye was introduced via trans-sacral catheter to check the adequacy of decompression. The disc height, lumbar lordosis, segmental lordotic angle on standing radiographs and Canal cross sectional area(CSA) on MRI were evaluated preoperatively and compared with postoperative images at the end of 1 year/final follow-up. The Visual analogue scale(VAS) for Back and Leg pain and Oswestry disability index (ODI), MacNab criteria, return to daily activities, return to work, patient satisfaction rate and recommendation to others were the clinical outcomes evaluated. The percentage of patients achieving the Minimal clinically important difference (MCID) of 3 points for VAS and 12 points for ODI was calculated. RESULTS: A total of 18 patients, with an average age of 35.1years (range 20-61), were operated. The mean VAS back improved from 5.7(±1.77) to 1(±0.77) and VAS leg improved from 7.3(±1.37) to 1.1(±1.09). The ODI improved from 49.88(±11.42) to 13.88(±7.28) at final follow-up. According to MacNab criteria, 17 patients had excellent and 1 had good outcome at final follow-up. The patient satisfaction rate was 90.5%, with 94% patient recommendation rate. All the patients returned to daily activities and work/modified work within a median of 5 weeks. There was 1 patient who required conversion to open surgery due to incidental dural tear, 1 patient who had a remnant disc required a revision tubular discectomy and 1 patient who had recurrence at 6 weeks and again at 2 years which was treated by repeat TELD. Five patients had impending cauda equina. All the patients achieved the MCID for VAS and ODI within a median period of 6 weeks and 3 months, respectively. The recovery rate was 90.1%. Five patients had grade 4 weakness of great toe/ankle dorsiflexion, one also had ankle flexion weakness preoperatively which improved after surgery. The CSA improved from a preoperative mean of 62.26(±30.3)mm2 to 122.16(±56.5)mm2 postoperatively. The CSA improved to 141.05(±63.86)mm2 at 1 year followup. The average disc height which was 9.71 mm(±2.4) was maintained at follow-up of one year which was 9.21 mm(±2.4). The lumbar lordosis and segmental lordotic angle changed from 27.08°(±15.9) and 2.82°(±5.7) to 35.8°(±8.56) and 4.85°(±4.39) respectively. CONCLUSION: TELD may be considered as an alternative to microdiscectomy or fusion procedures for huge central disc herniations with favourable outcomes. However, sufficient expertise with the procedure is necessary. Intraoperative decompression may be confirmed with intraoperative epidurography. The patient acceptability of the procedure is good and causes minimal disruption of the normal anatomy.

Subependymoma of the spine.

Subependymoma is a rare benign CNS tumor (WHO grade I). The common sites of origin for this type of tumor are the lateral and the fourth ventricles. A spinal intramedullary location is rare. Radiological features of intramedullary subependymoma can mimic more common and more aggressive tumor types. We report a case of a 61-year-old male who presented with a 3-year history of low back pain, associated with right lower limb progressive weakness and sensory numbness. An MRI of the lumbar spine revealed an intradural intramedullary lesion extending from the level of T10-L1. Clinical presentation, radiological, and pathological studies of this case of subependymoma are presented. The incidence of spinal subependymoma was also discussed in light of a literature review.