Endoscopic Surgical Treatment of Lumbar Synovial Cyst: Detailed Account of Surgical Technique and Report of 11 Consecutive Patients

Outcomes and adverse events for spinal synovial cysts surgical treatment: a systematic review and meta-analysis

BACKGROUND

Spinal synovial cysts (SSCs) are a rare cause of nerve root and spinal cord compression. Surgical excision of SSCs remains the mainstay of treatment in the presence of unremitting symptoms or neurological deficits, but the choice of the surgical approach remains controversial. The goal of this study was to compare clinical outcomes and adverse events associated with traditional approaches (interlaminar or laminectomy/hemilaminectomy) and minimally invasive approaches (microsurgical tubular approaches or endoscopic approaches) for SSCs.

METHODS

Studies reporting surgical management of SSCs were searched in three online databases (PubMed, the Cochrane Library, and Web of Science). This meta-analysis was reported following the PRISMA Statement. It was registered at the International Prospective Register of Systematic Reviews (CRD42021288992). The Cochrane Collaboration's Risk of Bias in Nonrandomised Studies-of Interventions (ROBINS-I) was used to evaluate bias. Extracted research data were statistically analyzed using Stata 16 and SPSS statistics 25.

RESULTS

A total of 22 related relevant studies were included. Meta-analysis revealed no statistically significant difference in dural tear, residual cyst, recurrence, reoperation, and operation time between minimally invasive approaches and traditional approaches (p > 0.05), but minimally invasive approaches had a good functional improvement (p = 0.004). Postoperative length of hospital stays and intraoperative bleeding in traditional approaches were also higher than in minimally invasive approaches (p < 0.05).

CONCLUSION

Based on the available evidence, minimally invasive approaches may be better than traditional approaches in the treatment of SSCs. Minimally invasive approaches had the advantages of improving clinical satisfaction, with a similar complication rate to traditional approaches. Moreover, endoscopic and microsurgical tubular approaches had similar outcomes.

Evaluation and Treatment of Lumbar Spine Extradural Cysts: A Narrative Review

The main objective was to describe the different types and characteristics of lumbar spine extradural cysts and their optimal treatment options with a focus on endoscopic technique. We searched Pubmed, EMBASE, Medline, and Google Scholar for articles published between 1967 and 2020 using the keywords "Spinal Cyst," "Extradural Cyst," and "Lumbar Cyst." The various anatomical and histological types of the extradural cysts with their presentations, etiologies, imaging, and optimal treatment with a focus on endoscopic techniques were reviewed from the articles. Lumbar spinal cysts are relatively rare pathologies that might cause radicular symptoms similar to lumbar disc herniation. Spinal extradural cysts are classified either histologically based on the cyst lining tissues (synovial cysts or non-synovial, ganglion cysts) or anatomically based on the structure of origin (epidural cysts, ligamentum flavum cysts, discal cysts, post-discectomy pseudocysts, posterior longitudinal ligament cysts, facet cysts). Surgical excision is the recommended treatment of symptomatic cysts with endoscopic techniques being a viable option. Extradural lumbar cysts can be identified based on their histological structure or depending on their structure of origin. Regardless of their classification, they could all give similar clinical findings, and the optimal treatment would be surgical excision with endoscopic technique being a viable option with a satisfactory outcome.

Efficacy of minimally invasive tubular approaches for management of the lumbar spinal synovial cysts: a meta-analysis

The treatment of lumbar spinal synovial cysts (LSCs) which are relatively rare but can cause neurogenic dysfunction and intractable pain has been a controversial topic for many years. Surgical excision of LSCs is the standard treatment for patients in whom conservative treatment options fail. This meta-analysis was undertaken to compare clinical outcomes between minimally invasive approaches using tubular retractors (microscopic vs. endoscopic) and traditional percutaneous approaches for LSCs. Studies reporting surgical management of LSCs were searched in the Cochrane Library, PubMed and Web of Science database. This meta-analysis was reported following the PRISMA Statement, registered in Prospero (CRD42021288992). A total of 1833 patients were included from both the related relevant studies (41 studies, n = 1831) and the present series (n = 2). Meta-analysis of minimally invasive tubular approaches revealed no statistically significant difference in pain improvement, dural tear, residual cyst, recurrence and operation time between minimal groups with traditional groups (p > 0.05). Minimal groups had better Functional improvement of 100% (95% CI 1.00-1.00; p < 0.001, I2 = 75.3%) and less reoperation rates of 0% (95% CI - 0.00-0.00; p = 0.007, I2 = 47.1%). Postoperative length of hospital stay and intraoperative bleeding in minimal groups were also less than traditional groups (p < 0.05). Subgroup analysis revealed endoscopic groups had less operation time (p = 0.004), and there was no significant difference in the rest. For patients with LSCs but without obvious clinical and imaging evidence of vertebral instability, even when preoperative stable grade 1 spondylolisthesis is present, minimally invasive tubular approaches without fusion may provide the best outcome in surgical management.

Microendoscopic Surgery for Degenerative Disorders of the Cervical and Lumbar Spine: The Influence of the Tubular Workspace on Instrument Angulation, Clinical Outcome, Complications, and Reoperation Rates

BACKGROUND

Long-term clinical outcomes with microendoscopic spine surgery (MESS) are poorly investigated. The effect of instrument angulation on clinical outcomes has yet to be assessed.

METHODS

A total of 229 consecutive patients operated on via two MESS systems were analyzed. Instrument angulation for both MESS systems, which differ from each other regarding the working space for instruments, was assessed using a computer model. Patients' charts and endoscopic video recordings were reviewed to determine clinical outcomes, complications, and revision surgery rates. At a minimum follow-up of two years, clinical outcomes were assessed employing the Neck Disability Index (NDI) and Oswestry Disability Index (ODI).

RESULTS

A total of 52 posterior cervical foraminotomies (PCF) and 177 lumbar decompression procedures were performed. The mean follow-up was six years (range 2-9 years). At the final follow-up, 69% of cervical and 76% of lumbar patients had no radicular pain. The mean NDI was 10%, and the mean ODI was 12%. PCF resulted in excellent clinical outcomes in 80% of cases and 87% of lumbar procedures. Recurrent disc herniations occurred in 7.7% of patients. The surgical time and repeated procedure rate were significantly lower for the MESS system with increased working space, whereas the clinical outcome and rate of complication were similar.

CONCLUSIONS

MESS achieves high success rates for treating degenerative spinal disorders in the long term. Increased instrument angulation improves access to the compressive pathology and lowers the surgical time and repeated procedure rate.

Percutaneous Full Endoscopic Management of Spinal Foraminal Schwannomas: Case Series

BACKGROUND

Schwannoma, a benign peripheral nerve sheath tumor, is perhaps only secondary to degenerative pathology as the most common lesion at neural foramen. The surgical dilemma here is either risking nerve injury because of inadequate exposure or the need for internal fixation because of facet joint sacrifice.

OBJECTIVE

To evaluate the feasibility and safety of management of foraminal schwannomas by percutaneous full-endoscopic technique.

METHODS

A single-center retrospective review was conducted on patients who underwent full-endoscopic resection of neural foraminal schwannomas. Tumors were grouped into either medial type or lateral type based on relevant location to the neural foramen, and respective surgical approaches were adopted. Data including preoperative neurological status, tumor size, surgery time, the extension of resection, and clinical outcomes were collected. The learning curve was plotted as surgical time/tumor size against case number.

RESULTS

A total of 25 patients were treated between May 2015 and March 2022. Gross total resection was achieved in 24 patients, and near-total resection in 1 case, with 1 patient experienced transient voiding difficulty. No tumor recurrence or spinal instability was detected in the short-term follow-up (median follow-up 22 months, range 3 months-6 years). Surgical efficiency improved with the number of cases operated on and remained stable after the initial 10 cases.

CONCLUSION

Percutaneous full-endoscopic technique is a safe and minimally invasive technique for the resection of foraminal schwannomas.

Awake transforaminal endoscopic lumbar facet cyst resection: technical note and case series

OBJECTIVE

The aim of this study was to describe a minimally invasive transforaminal surgical technique for treating awake patients presenting with lumbar radiculopathy and compressive facet cysts.

METHODS

Awake transforaminal endoscopic decompression surgery was performed in 645 patients over a 6-year period from 2014 to 2020. Transforaminal endoscopic decompression surgery utilizing a high-speed endoscopic drill was performed in 25 patients who had lumbar facet cysts. All surgeries were performed as outpatient procedures in awake patients. Nine of the 25 patients had previously undergone laminectomies at the treated level. A retrospective chart review of patient-reported outcome measures is presented.

RESULTS

At the 2-year follow-up, the mean (± standard deviation) preoperative visual analog scale leg score and Oswestry Disability Index improved from 7.6 ± 1.3 to 2.3 ± 1.4 and 39.7% ± 8.1% to 13.0% ± 7.4%, respectively. There were no complications, readmissions, or recurrence of symptoms during the 2-year follow-up period.

CONCLUSIONS

A minimally invasive awake procedure is presented for the treatment of lumbar facet cysts in patients with lumbar radiculopathy. Approximately one-third of the treated patients (9 of 25) had postlaminectomy facet cysts.

Minimally Invasive Surgical Decompression without Fusion for the Treatment of Lumbar Synovial Cysts: Feasibility and Long-Term Outcomes

BACKGROUND

Lumbar synovial cysts (LSCs) can cause painful radiculopathy and sensory and/or motor deficits. Historically, first-line surgical treatment has been decompression with fusion. Recently, minimally invasive laminectomy without fusion has shown equal or superior results to traditional decompression and fusion methods.

OBJECTIVE

This study investigates the long-term efficacy of minimally invasive laminectomy without fusion in the treatment of LSC as it relates to the rate of subsequent fusion surgery.

METHODS

A retrospective review was performed over a 10-year period of patients undergoing minimally invasive laminectomy for symptomatic LSCs. The primary end point was the rate of revision surgery requiring fusion.

RESULTS

Eighty-five patients with symptomatic LSCs underwent minimally invasive laminectomy alone January 2010-August 2020 at our institution. The most common location was L4-5 (72%). Preoperative imaging identified spondylolisthesis (grade 1) in 43 patients (57%), none of which was unstable on available dynamic radiographs. Average procedure duration was 93 minutes, with 78% of patients discharged home on the same day of surgery. Over 46 months of mean follow-up, 17 patients (20%) required 19 revision operations. Of those operations, 16 were spinal fusions (17.6%). Median time to fusion surgery was 36 months. There were no identifiable risk factors on multivariate regression analysis that predicted the need for fusion.

CONCLUSIONS

Minimally invasive laminectomy is an effective first-line treatment for symptomatic LSCs and avoids the need for fusion in most treated patients. Of our patients, 18% required a fusion over 46 months, suggesting that further studies are required to guide patient selection.

Spinal endoscopy: evidence, techniques, global trends, and future projections

The utilization of indirect visualization during procedures has been increasingly replacing traditional forms of direct visualization across many different surgical specialties. The adoption of arthroscopy, using small cameras placed inside joints, has transformed musculoskeletal care over the last several decades, allowing surgeons to provide the same anatomic solutions with less tissue dissection, resulting in lower requirements for inpatient care, reduced costs, and expedited recovery.  For a variety of reasons, spine surgery has lagged behind other specialties in the adoption of indirect visualization.  Nonetheless, patient demand for less invasive spine procedures and surgeon drive to provide these solutions and improve care quality has driven global adoption of spinal endoscopy.  There are numerous endoscopic platforms and techniques currently utilized, and these systems are rapidly evolving.  Additionally, the variance in technology and health system incentives across the globe has generated tremendous regional heterogeneity in the utilization of spinal endoscopic procedures.  We present a consolidated review, including the background, evidence, techniques, and trends in spinal endoscopy, so that clinicians can gain a deeper understanding of this rapidly evolving domain of spinal healthcare.

Outcomes and complications following minimally invasive excision of synovial cysts of the lumbar spine: A systematic review and meta-analysis

OBJECTIVE

Lumbar synovial cysts (LSC) are one of the manifestations of spinal degenerative cascade. Spinal stenosis or presence of instability in these patients can lead to various symptoms and surgery is indicated following failure of non-operative management for symptomatic synovial cysts. Surgery when performed consists of either decompression with resection of cyst with our without fusion. The efficacy and complications of minimally invasive techniques using tubular retractors (microscopic or endoscopic) in comparison to traditional open techniques remain to be studied.

METHODS

A comprehensive search of different databases was performed to retrieve studies describing the use of minimal invasive techniques using tubular retractors (both microscopic and endoscopic) in patients with LSC. Meta-analysis with subgroup analysis and metaregression was done.

RESULTS

Twenty articles were selected for the systematic review and meta-analysis with total of 388 patients. Eighty-six percent of patients (95% Confidence Interval (CI): 80-90%) had favorable outcome as per Macnab's criteria (excellent and good outcome) with the pooled standard mean difference between preoperative and postoperative Oswestry Disability Index (ODI) being -4.44 (95% CI -8.78 to -0.10, p-value=0.0474, I² 82%). The pooled percentage change in visual analogue scale (VAS) after surgery was 76.5% (95% CI 66.9-84%, I² 82%). The pooled proportion of incidental durotomies, cyst recurrence and patients requiring operation being 8% (95% CI 5-11%, I² 0%), 4% (95% CI 2-7%, I² 0%,) and 5% (95% CI 3-9%) respectively. Studies were homogeneous with an I² value of 0%. Subgroup analysis revealed no significant difference in the outcome rates or complication rates between the microscopic and endoscopic subgroups.

CONCLUSION

Minimally invasive techniques for the resection of LSC is a safe and effective alternative to traditional surgical approaches with no difference between the microscopic and endoscopic approaches.

Microendoscopic decompression for lumbar spinal stenosis caused by facet-joint cysts: a novel technique with a cyst-dyeing protocol and cohort comparison study

OBJECTIVE

Facet cysts may represent a sign of intrinsic facet disease and instability, increasing the importance of less-invasive approaches that limit tissue dissection and improve visualization. The authors developed an intraoperative cyst-dyeing technique, involving the injection of indigo carmine from the facet joint into the cyst, as an adjunct during decompression. This study aimed to evaluate the clinical outcomes and perioperative complication rates of microendoscopic spinal decompression for lumbar spinal stenosis (LSS) and lumbar foraminal stenosis (LFS), caused by facet cysts and to elucidate the efficacy of the cyst-dyeing method in microendoscopic surgery for facet cysts.

METHODS

Forty-eight consecutive patients who underwent surgical treatment with microendoscopic decompression for symptomatic LSS or LFS caused by facet cysts from 2011 to 2018 were reviewed. These patients were divided into two groups: a group that did not receive dye (N), with the patients undergoing surgery from April 2011 to May 2015; and a group that received dye (D), with patients undergoing surgery from June 2015 to March 2018. The authors evaluated the operative time, blood loss, perioperative complications, visual analog scale scores for low-back and leg pain, and Japanese Orthopaedic Association scores. Surgical outcome was evaluated 2 years postoperatively and was compared between groups D and N.

RESULTS

The clinical outcomes were generally excellent or good. Group N consisted of 36 patients and group D of 12 patients. Comparing the clinical results, it was found that the cyst-dyeing method reduced the perioperative complication rate, including reduction in dural tears to 0%, and shortened the average operative time by approximately 40 minutes.

CONCLUSIONS

In this study, the authors demonstrated that the clinical outcomes of microendoscopic spinal decompression in patients with LSS or LFS caused by facet-joint cysts are generally favorable. Additionally, the adjunctive cyst-dyeing method effectively delineated the cystic and dural boundaries, facilitating safer and more effective cyst separation and neural decompression. Microendoscopic surgery combined with this novel facet cyst-dyeing method is a safe and effective minimally invasive technique for facet-joint cysts.

Is Decompression and Partial Discectomy Advantageous Over Decompression Alone in Microendoscopic Decompression Of Monosegmental Unilateral Lumbar Recess Stenosis?

BACKGROUND

Endoscopic techniques are well accepted as surgical technique for decompression of lumbar lateral recess stenosis (LRS). It is uncertain if there is a difference in clinical outcome for decompression alone (DA) or decompression with partial discectomy (DPD) for the treatment of LRS.

METHODS

All files of patients who underwent an endoscopic procedure for lumbar LRS were identified from a prospectively collected database. Preoperative magnetic resonance imaging and endoscopic video were analyzed with special focus on the technique of nerve root decompression. Clinical outcome was assessed via a personal examination, a standardized questionnaire including the numeric rating scale (NRS) for leg and back pain, the Oswestry disability index (ODI), and the modified MacNab criteria to assess functional outcome and clinical success.

RESULTS

Sixty-six patients were identified of which 57 attended for evaluation (86.4%). DA was performed in 15 (26.3%) patients and DPD in 42 patients (73.7%). The mean follow-up was 45.0 months (range: 16-82 months). Fifty-two patients reported to be free of leg pain (91.1%), 42 patients had no noticeable back pain (73.7%), 49 patients had full muscle strength (85.9%), and 48 patients had no sensory disturbance (84.2%). The mean NRS for leg pain was 1, the mean NRS for back pain was 2, mean ODI was 16% (range: 0%-60%). Clinical success was noted in 49 patients (85.9%) and it was significantly higher for patients following DPD (P = .024). The overall repeat procedure rate was 12% with reoperation rate at the index segment in 10.5% of cases. There were no significant differences with respect to leg and back pain, ODI, and reoperation between both groups.

CONCLUSION

Microendoscopic DPD of LRS achieves a 92% clinical success rate which is significantly higher compared to 67% clinical success achieved by DA. There was no significant difference for the rate of reoperation, leg and back pain, and ODI.

LEVEL OF EVIDENCE

4.

The Feasibility and Perioperative Results of Bi-Portal Endoscopic Resection of a Facet Cyst Along With Minimizing Facet Joint Resection in the Degenerative Lumbar Spine

BACKGROUND

Presentation of degenerative facet cysts (FC) as radicular pain in patients is well established. The traditional treatment of FCs has been decompressive laminectomy with a medial facetectomy and cyst excision. A major disadvantage of open procedures with medial facetectomy is predisposition to further instability.

OBJECTIVE

To describe a contralateral bi-portal endoscopic excision of FC along with minimizing facet joint resection.

METHODS

Thirteen patients between March 2016 and December 2017 were evaluated retrospectively for clinical, radiological, and morphometric outcomes. Patients with complaints of unilateral radiculopathy with associated neurogenic claudication from degenerative lumbar FC were included. Clinical evaluation was by NRS leg pain and ODI scores, radiological evaluation was by MRI. For morphometric analysis, cross-sectional area of facet joint (CSA-FJ) was measured on MRI in square millimeters.

RESULTS

Thirteen FCs were decompressed (no adverse events) NRS leg pain and ODI improved from 6.85 ± 0.69 and 65.08 ± 7.95 preoperatively to 1 ± 0.91 and 13.46 ± 5.19 at 1-yr follow-up, respectively. CSA-FJ remained relatively well preserved from 212.83 ± 58.05 to 189.77 ± 62.93 post decompression (statistically insignificant, P = .3412).

CONCLUSION

Bi-portal endoscopic decompression of FC can be performed with good clinical and radiological outcomes. This surgical technique may be recommended for further evaluation as an addition in the armamentarium of a spine surgeon for treatment of degenerative lumbar FC.

Full-Endoscopic Removal of Lumbar Juxtafacet Cysts: A Prospective Multicentric Study

BACKGROUND

Lumbar juxtafacet cysts are benign lesions that grow at the level of facet joints or within neighboring structures. Recently, there is an ongoing trend toward less invasive procedures for treating degenerative spine diseases. Here we report a multicenter study of full-endoscopic surgery for juxtafacet cyst removal.

METHODS

We prospectively collected patients with a diagnosis of lumbar juxtafacet cyst surgically treated in 3 institutions between January 2017 and August 2019. Patients of any sex and age were eligible if they had a single level unilateral lumbar juxtafacet cyst, invalidating radicular pain lasting >6 weeks, adequate imaging, and failed percutaneous or conservative treatment. Age at diagnosis; sex; preoperative, postoperative, and 6-month leg pain; surgical and medical complications; spine instability (preoperatively and at 6 and 12 months); and follow-up time were collected.

RESULTS

Thirty-five patients were enrolled. Median operative time was 78 minutes, and mean leg pain went from a preoperative value of 6.8 (standard deviation [SD] = 1.2) to a postoperative value of 3.4 (SD = 1.1, P < 0.001) to 2.1 (SD = 1.7, P < 0.001) at 6 months. At a median follow-up of 15 months, approximately 89% of patients were pain-free or improved. We had 2 recurrences of radicular pain, treated conservatively. Only 2 surgical complications (6%) occurred: 2 small dural tears, both resolved without further intervention.

CONCLUSIONS

Full-endoscopic surgery is feasible and safe for juxtafacet cyst removal. Our results are consistent with findings from recent full-endoscopic and series, with outcomes overlapping those reported for open or tubular techniques.

Long-term pain relief following percutaneous steroid treatment of spinal synovial cysts: a population-based cohort study

BACKGROUND

Spinal synovial cysts are fluid-filled sacs that develop after facet joint degeneration and can give rise to radicular pain. If resistant to conservative management, surgical decompression or percutaneous steroid treatment is usually recommended. Percutaneous treatment minimizes the risk of spinal instability, but it has been uncertain whether it provides any long-term symptom relief. Moreover, it is unclear whether cyst rupture provides any added benefit.

OBJECTIVE

To assess long-term pain relief in patients with spinal synovial cysts who were treated with percutaneous intra-articular steroid treatment without cyst rupture.

METHODS

A population-based cohort-study was conducted of all patients with symptomatic synovial cysts who were treated with percutaneous intra-articular steroid treatment without cyst rupture between 1995 and 2014.

RESULTS

Thirty-eight patients were included. All patients had variations of lower back and radicular pain. Intra-articular access was achieved in 35 (92%) patients, and there were no treatment-related complications. At short-term assessment, 30 (79%) had pain relief. During the median follow-up of 11 years, 12 (32%) patients showed sustained pain relief without the need for decompressive surgery.

CONCLUSIONS

Percutaneous intra-articular steroid treatment without cyst rupture is a safe treatment for symptomatic spinal synovial cysts and eliminates the need for surgery in a substantial number of patients. It can be suggested as a first line of treatment.

OLIF Combined with Anterior Fixation for Lumbar Synovial Cysts with Instability

BACKGROUND

The optimal management of lumbar synovial cysts (LSCs) has always been controversial. Open or minimally invasive partial hemilaminotomy as a direct decompression approach has been widely studied, whereas to our knowledge, there has been no report of an indirect decompression method for LSC.

CASE DESCRIPTION

A 60-year-old male complained of chronic low back pain for 2 years. He reported that the pain had been getting worse and started radiating to the bilateral posterior thighs and right lateral calf for 6 months. An ovoid lesion with a hyperintense center attached to the medial side of the right facet joint at the L4-5 level, as well as L4-5 dynamic instability, were found with magnetic resonance imaging and lumbar x-ray examinations, respectively. L4-5 oblique lumbar interbody fusion combined with anterior fixation was performed. After surgery, the patient felt distinct pain relief and was discharged on the third day postoperatively. Three months later, lumbar magnetic resonance imaging and 3-dimensional computed tomography were performed again. The L4-5 disk height and foraminal height recovered from 7.1-12.3 mm and 14.8-18.5 mm, respectively. No evidence of a cyst was disclosed. The patient did not complain of any low back pain or radicular pain during the 12-month follow-up.

CONCLUSIONS

Indirect decompression surgery may be a new option for the management of LSC, especially in those with lumbar instability and that communicate with the facet joint. Further research with a larger and more comprehensive sample population is required.

The benefit zone of full-endoscopic spine surgery

Minimally invasive spine procedures have undergone rapid development during the last decade. Efforts to decrease muscle crush injuries during prolonged retraction, avoid significant soft tissue stripping and minimize bony resection are surgical principles that are employed to prevent iatrogenic instability and provide patients with decreased post-operative pain and disability. Full-endoscopic spine surgery represents a tool for the spine surgeon to provide targeted access to spinal pathology utilizing these principles. Endoscopic techniques have seen over 30 years of evolution and innovation, however, early iterations of these techniques largely focused on transforaminal lumbar microdiscectomies. Currently, endoscopic techniques are utilized for approaching pathology in the cervical, thoracic and lumbar spine. There has been a growing body of literature that not only confirms the efficacy of these procedures but also underscores the advantages these procedures offer with respect to less morbidity and safer complication profiles. Endoscopic decompressions have been utilized in the settings of degenerative spinal stenosis, spondylolisthesis, scoliosis, previous fusion, tumor and infection. Furthermore, endoscopic interbody fusion has also been utilized in the lumbar spine as technology continues to advance. As technological innovation continues to facilitate reproducible surgical technique and expand the indications for use, we believe that endoscopic spine surgical techniques will provide surgeons with a more powerful and less morbid approach to spinal pathology that ultimately elevates the standard of care when treating our patients. We present a brief review of the history of endoscopic spine surgery, an overview of current techniques and review current outcomes of endoscopic spine surgical procedures in the context of an invasiveness/complexity index to elucidate the benefit zone of these newer techniques.

[Minimally invasive resection of spinal synovial cysts: Technical note]

Objetivo:

Presentar el algoritmo de tratamiento, técnica quirúrgica y resultados de una serie de pacientes con quistes sinoviales espinales resecados con técnica mínimamente invasiva (MIS).

Introducción:

Los quistes sinoviales espinales se originan a partir de la dilatación y potencial ruptura de la vaina sinovial de una articulación facetaria, la resección quirúrgica es considerada el tratamiento de elección en pacientes sintomáticos. La utilización de técnicas MIS podrían disminuir la disrupción de la faceta articular comprometida reduciendo el riesgo de inestabilidad postoperatoria.

Material y métodos:

Se evaluaron retrospectivamente 21 pacientes con quistes sinoviales espinales operados mediante abordaje y descompresión MIS, se analizaron los signos, síntomas, tiempo quirúrgico, estadía hospitalaria, evolución y complicaciones. Se utilizó la escala visual analógica (EVA), para evaluar el dolor y la escala de Weiner y los criterios de Macnab modificados para medir la satisfacción posoperatoria del paciente.

Resultados:

Se trataron quirúrgicamente 21 pacientes (13 mujeres, 8 hombres), el 76,2% (n = 16) de los pacientes de la serie no requirió artrodesis, el 23,8% (n = 5) restante fue fusionado. Realizamos 13 (61,9%) hemilaminectomías contralaterales, 7 hemilaminectomías ipsilaterales (33,3%) y una laminectomía en el QS S1-S2 con técnica MIS. El seguimiento promedio fue de 26 meses, el tiempo de cirugía fue de 150,33 ± 63,31 min., con una estadía hospitalaria de 2,5 ± 1,78 días. La EVA disminuyó de 8,3 preoperatoria a 2,3 postoperatoria. Siguiendo la escala de Macnab; 16 pacientes refirieron resultados excelentes, 4 buenos y 1 regular, el 95,2% de los pacientes percibió que el procedimiento tuvo mucho/bastante éxito según la escala de Weiner.

Conclusión:

El abordaje mínimamente invasivo es un procedimiento seguro y eficaz para la resección completa de quistes sinoviales espinales. Proporciona resultados clínico-funcionales excelentes preservando músculos, ligamentos y facetas articulares.

Endoscopic spinal surgery using a new tubular retractor with 15 mm outer diameter

Purpose: To assess whether the instrument handling and image quality of endoscopic spinal decompression procedures is adequate and effects the treatment of degenerative spinal disorders. Material and Methods: Forty-six patients underwent endoscopic procedures for radicular pain or sensorimotor deficit due to a degenerative disorder using a 15mm tubular retractor. Endoscopic video recordings were reviewed with focus on instrument handling and intraoperative complication. At final follow-up the clinical outcome was assessed via a standardized questionnaire including the Oswestry Disability Index (ODI) Neck Disability Index (NDI), Odoms criteria and a personal examination focusing on pain, and sensorimotor deficits. Results: Forty out of 46 patients attended a final follow-up (86.9%). The mean follow-up time was 51.8 month (range 15-84 month). At final follow-up, of patients who were operate at the lumbar spine 93.9% and at the cervical spine 85.7% were free of radicular pain, no weakness was documented in 84.9% of cases after lumbar and 85.7% after cervical spine procedure, and according to Odoms criteria clinical success was noted in 84.5% and 100%, respectively. The mean ODI was 9.0% and mean NDI was 11.7%. The dural tear rate was 4.3%, all dural tear were closed endoscopically. The recurrent disc herniation rate was 6.1%. Conclusions: Endoscopic decompression using a 15m tubular retractor offers a good view onto the surgical field and a high clinical success rate. The decompression of degenerative pathologies in bimanual technique is not limited by a 15mm tubular retractor.

Surgical Treatment of Extra-Foraminal Gas Containing Pseudocyst Compressing L5 Nerve Root by Using Unilateral Biportal Endosopy: A Case Report

BACKGOUND

Most gaseous lumbar pseudocysts have been previously reported to be located in the spinal canal and successfully treated by several therapeutic methods. By comparison, a gas containing pseudocyst in lumbar extra-foraminal area is very rare. Here, the authors report a case of symptomatic gas containing cyst located in lumbar foramen. It was successfully treated with unilateral biportal endoscopic (UBE) surgery.

CASE DESCRIPTION

a 75-year-old man presented with severe left leg pain and tingling sensation refractory to conservative treatment that aggravated with weight bearing and position change. Computed tomography and magnetic resonance imaging showed a gas containing cyst compressing the left L5 nerve root ganglion in the foramina area at L5-S1 level. Gaseous extra-foraminal pseudocyst was successfully removed by UBE surgery via para-spinal approach. Vivid and clear endoscopic operative imaging of pseudocyst in detail was obtained during operation. The patient's symptom was significantly improved after the operation.

CONCLUSIONS

Gas containing pseudocyst in lumbar foraminal area is not common. Combined use of pre-operative MRI and CT can help diagnose gaseous pseudocyst and differentiate other pathologies. UBE technique which provides good operative visualization and delicate operative manipulation is a less invasive therapeutic method to treat foraminal gas containing pseudocyst.

Degenerative symptomatic spinal synovial cysts: Clinical presentation and functional outcome

Spinal synovial cysts (SSC) are a rare but important differential diagnosis for degenerative or space-occupying spinal lesions. There is controversy about the most beneficial treatment, which can be conservative or surgical. We provide a review of our surgical data for purposes of quality assessment and improvement. 5313 patients with surgically treated degenerative spinal diseases were analyzed retrospectively. The incidence of SSC was 1.14%. 61 patients (31 women, 30 men; mean age 65.3 years) with SSC were included in this study. The charts, surgical reports, and radiographic data were reviewed for demographics, duration of symptoms, size of SSC, anatomical site, surgical approach, Visual Analog Scale (VAS), and neurological performance including the Japanese Orthopedic Association Score (JOA score) and the Frankel score. Laminotomy was the most common surgical approach in 93.4% of the patients followed by hemilaminectomy in 6.6%. The predominant site of SSC was the lumbar spine in 86.9%. 95.1% had experienced local and radicular pain as the predominant symptom and 47.5% preoperative sensory and motor deficits. At discharge, the JOA score was significantly increased compared to admission (median value of 17). At follow-up, 94.4% had normal neurological function and 5.6% showed grade 1 neurological deficits. Leg pain had decreased in 94.4% and back pain in 70.6%. At long-term follow-up, all patients presented neurologically stable. The median value for pain classified with the VAS had decreased from 6 at admission to 1 at long-term follow-up. During long-term follow-up, 6 patients (9.8%) had developed spinal instability requiring stabilization, 5 patients had received facet joint infiltration due to symptomatic facet joint syndrome. The epidemiological and clinical patterns of symptomatic SSC are similar to those of other degenerative spinal diseases. Thus, SSC should always be considered as a rare but important differential diagnosis. Surgical outcome was excellent with immediate symptom relief and recovery, which further improved over time. Our data support the benefit of surgical treatment and may be useful in recommending neurosurgical therapy to patients with SSC.

The Learning Process of Endoscopic Spinal Surgery for Degenerative Cervical and Lumbar Disorders Using the EasyGO! System

BACKGROUND

Among spinal surgeons, the safety of endoscopic spinal techniques has been criticized as the result of a prolonged learning curve and divergent surgical technique from traditional microsurgery. In this manuscript, the authors assessed the learning curve of 4 experienced microsurgical neurosurgeons in endoscopic spinal surgery.

METHODS

Retrospectively, the surgical reports, the endoscopic video recording, and the files of all patients who underwent an endoscopic procedure for the treatment of cervical and lumbar disc herniation from January 2011 to December 2017 were reviewed. The learning process was assessed via several parameters: surgical time, intraoperative complications, dural tear, nerve root injury, conversion to microsurgery, new postoperative neurologic deficits, repeated procedure, and early recurrent disc herniation.

RESULTS

The learning process of for 4 surgeons was assessed on the basis of 308 procedures. The mean surgical time for the initial procedure ranges from 58 to 97 minutes and improved to 51-85 minutes for the last procedures. A shorter surgical time had no influence on the rate of intraoperative complication and repeated procedure. Increased working space had a significant influence on the surgical time. The number of procedure to reach the asymptote varied from 10 to 20 depending on the endoscopic system and the surgeon.

CONCLUSIONS

The learning process in endoscopic tubular-assisted spinal surgery is variable, and the asymptote might be reached after 10-20 procedures. The amount of working space and instrument angulation affects the surgical time. The decrease of surgical time had no significant influence on the rate of intraoperative complication and repeated procedures.