Recurrent back and leg pain and cyst reformation after surgical resection of spinal synovial cysts: systematic review of reported postoperative outcomes

Evolution of lumbar degenerative spondylolisthesis with key radiographic features

Spondylolisthesis is a common finding in middle-aged and older adults with back pain. The pathophysiology of degenerative spondylolisthesis is a subject of controversy regarding not only its etiology but also the mechanisms of its progression. It is theorized that degeneration of the facets and discs can lead to segmental instability, leading to displacement over time. Kirkaldy-Willis divided degenerative spondylolisthesis into three phases: dysfunction, instability, and finally, restabilization. There is a paucity of literature on the unification of the radiological hallmarks seen in spondylolisthesis within these phases. The radiographic features include (1) facet morphology/arthropathy, (2) facet effusion, (3) facet vacuum, (4) synovial cyst, (5) interspinous ligament bursitis, and (6) vacuum disc as markers of dysfunction, instability, and/or restabilization. We discuss these features, which can be seen on X-ray, CT, and MRI, with the intention of establishing a timeline upon which they present clinically. Spondylolisthesis is initiated as either degeneration of the intervertebral disc or facet joints. Early degeneration can be seen as facet vacuum without considerable arthropathy. As the vertebral segment becomes increasingly dynamic, fluid accumulates within the facet joint space. Further degeneration will lead to the advancement of facet arthropathy, degenerative disc disease, and posterior ligamentous complex pathology. Facet effusion can eventually be replaced with a vacuum in severe facet osteoarthritis. Intervertebral disc vacuum continues to accumulate with further cleft formation and degeneration. Ultimately, autofusion of the vertebra at the facets and endplates can be observed. With this review, we hope to increase awareness of these radiographical markers and their timeline, thus placing them within the framework of the currently accepted model of degenerative spondylolisthesis, to help guide future research and to help refine management guidelines.

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.

Risk of Subsequent Fusion After Isolated Decompression of Lumbar Facet Cysts

INTRODUCTION

Lumbar facet cysts represent a potential source of nerve root compression in elderly patients. Isolated decompression without fusion has proven to be a reasonable treatment option in properly indicated patients. However, the risk of lumbar fusion after isolated decompression and facet cyst excision has yet to be elucidated.

METHODS

The PearlDiver database was reviewed for patients undergoing isolated laminectomy for lumbar facet cyst from January 2015 to December 2018 using Current Procedural Terminology coding. Patients undergoing concomitant fusion or additional decompression, as well as those diagnosed with preexisting spondylolisthesis or without a minimum of 5-year follow-up, were excluded. Rates of subsequent lumbar fusion and potential risk factors for subsequent fusion were identified. Statistical analysis included descriptive statistics, chi square test, and multivariate logistic regression. Results were considered significant at P < 0.05.

RESULTS

In total, 10,707 patients were ultimately included for analysis. At 5-year follow-up, 727 (6.79%) of patients underwent subsequent lumbar fusion after initial isolated decompression. Of these, 301 (2.81% of total patients, 41.4% of fusion patients) underwent fusion within the first year after decompression. Multivariate analysis identified chronic kidney disease, hypertension, and osteoarthritis as risk factors for requiring subsequent lumbar fusion at 5 years following the index decompression procedure ( P < 0.033; all).

CONCLUSION

Patients undergoing isolated decompression for lumbar facet cysts undergo subsequent lumbar fusion at a 5-year rate of 6.79%. Risk factors for subsequent decompression include chronic kidney disease, hypertension, and osteoarthritis. This study will assist spine surgeons in appropriately counseling patients on expected postoperative course and potential risks of isolated decompression.

Articular arthrodesis with the facet wedge technique for the treatment of unstable lumbar degenerative disease and associated conditions: A retrospective study of 96 patients

Background

Lumbar articular fusion with the facet wedge (FW) technique is gaining increasing interest among surgeons for the treatment of vertebral instability due to its limited invasiveness and ease of use. Studies on cadavers have reported biomechanical properties similar to pedicle screws. Yet, the evidence supporting their use is still limited and moreover focused only on spinal degenerative disease.

Methods

96 cases of lumbar articular fusion with the FW techniques performed at 3 different centers between 2014 and 2022 were retrospectively analyzed based on the specific surgical indications: 1) degenerative spondylolisthesis/unstable lumbar stenosis; 2) synovial cysts; 3) adjacent segment disease (ASD). Medical records were reviewed to identify rates of complications and measures of functional outcome (ODI, low back pain VAS and modified Macnab scale) were collected both at baseline and at the follow-up visits. Wilcoxon signed-rank test was adopted to test for significant functional improvements.

Results

Significative clinical improvements were observed from baseline to follow-up regarding ODI and VAS scores. Overall rate of moderate and severe complications (according to Landriel-Ibañez scale) was 7.9%. Only 3.4% of patients with degenerative disease developed ASD requiring reoperations. Only one case of radicular deficit and one of device mobilization were reported. 2/4 cases of synovial cysts treated with unilateral fusions developed contralateral complications. 9 out of 16 (56.25%) patients who underwent long-term postoperative CT scans presented adequate degree of articular fusion.

Conclusion

FW technique is easy, safe, and effective. Its low rate of complications justifies its use for cases of mild lumbar instability.

FactFinders for patient safety: Understanding potential procedure-related complications: RFN/multifidus atrophy, intradiscal biologics, and facet cyst rupture

This series of FactFinders presents a brief summary of the evidence and outlines recommendations to improve our understanding and management of several potential procedure-related complications. The evidence in support of the following facts is presented: (1) Multifidus Atrophy After Lumbar Medial Branch Radiofrequency Neurotomy (LMBRFN) -- There is no conclusive published literature indicating that LMBRFN leads to increased multifidus atrophy relative to natural history. High-quality prospective studies with a natural history comparison group evaluating immediate pre-procedure as well as post-procedure longitudinal cross-sectional imaging are needed to accurately assess for any possible influence of LMBRFN on multifidus atrophy as well as the clinical relevance. (2) Intradiscal Biologics -- Although the available evidence on intradiscal biologic interventions is limited, it nonetheless shows a non-zero risk of complications. Until larger sample sizes are reported, the actual magnitude of the risk cannot be ascertained. In the meantime, physicians who perform intradiscal injections of biologics should conscientiously consider the risk-benefit of these procedures. (3) Lumbar Facet Synovial Cyst Rupture -- There have been few reports of complications secondary to lumbar facet synovial cyst rupture. Risks of may include increased pain, infection, and nerve root compression.

Decompression with or without Fusion for Lumbar Synovial Cysts—A Systematic Review and Meta-Analysis

The management of symptomatic lumbar synovial cysts (LSC) is still a matter of debate. Previous systematic reviews did not stratify data according to different treatment techniques or incompletely reported comparative data on patients treated with lumbar posterior decompression (LPD) and lumbar decompression and fusion (LDF). The aim of our study was to compare LPD and LDF via a systematic review and meta-analysis of the existing literature. The design of this study was in accordance with the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The review questions were as follows: among patients suffering from symptomatic lumbar synovial cysts (population) and treated with either posterior lumbar decompression or posterior decompression with fusion (intervention), who gets the best results (outcome), in terms of cyst recurrence, reoperation rates, and improvement of postoperative symptoms (comparison)? The search of the literature yielded a total of 1218 results. Duplicate records were then removed (n = 589). A total of 598 articles were screened, and 587 records were excluded via title and abstract screening; 11 studies were found to be relevant to our research question and were assessed for eligibility. Upon full-text review, 5 were excluded because they failed to report any parameter separately for both LPD and LDF. Finally, 6 studies for a total of 657 patients meeting the criteria stated above were included in the present investigation. Our analysis showed that LDF is associated with better results in terms of lower postoperative back pain and cyst recurrence compared with LPD. No differences were found in reoperation rates and complication rates between the two techniques. The impact of minimally invasive decompression techniques on the different outcomes in LSC should be assessed in the future and compared with instrumentation techniques.

Efficacy of Percutaneous Image-Guided Rupture of Lumbar Facet Cysts: A Retrospective Study

Background

Percutaneous rupture of lumbar facet cysts (LFC) is the only nonsurgical treatment which is effective in directly reducing cysts. However, this is not yet a common procedure, and its effectiveness, including the associated complications, remains unclear. Therefore, this study aimed to evaluate the clinical outcomes of percutaneous rupture for LFC and elucidate whether this minimally invasive procedure could become an alternative to surgeries for cases resistant to conservative treatments.

Methods

This study investigated 57 symptomatic patients with LFC for whom conservative treatments were ineffective and underwent percutaneous rupture of the LFC. All patients were followed up for >2 years posttreatment. Clinical evaluations (visual analogue scale (VAS) and recovery rate calculated using the Japanese Orthopedic Association (JOA) scores) and radiographic evaluations (size of LFC based on magnetic resonance imaging (MRI)) were performed from pretreatment to the final follow-up examination.

Results

Successful LFC rupture, without hospitalization and general anesthesia, was achieved in 48 patients. No severe complications occurred during treatment through the last observation. Satisfactory clinical results with significant improvements in the VAS and JOA scores were obtained (VAS: pre/posttreatment: 80.7 mm/11.2 mm, JOA: pre/posttreatment: 15.6 points/26.7 points, and recovery rate: 82.3%). A significant reduction in the LFC was also observed in all cases based on the posttreatment MRI findings. No successful rupture cases required subsequent surgical treatments, although four cases of LFC recurrence required additional percutaneous rupture treatment.

Conclusions

Percutaneous rupture for LFC is not only a safe and minimally invasive procedure without any severe complications or requirements for hospitalization and general anesthesia but also a beneficial procedure that can eliminate the need for surgery in cases resistant to conservative treatments.

Creation and validation of a predictive model for lumbar synovial cyst recurrence following decompression without fusion

OBJECTIVE

Lumbar synovial cysts (LSCs) represent a relatively rare clinical pathology that may result in radiculopathy or neurogenic claudication. Because of the potential for recurrence of these cysts, some authors advocate for segmental fusion, as opposed to decompression alone, as a way to eliminate the risk for recurrence. The objective of this study was to create a predictive score for synovial cyst recurrence following decompression without fusion.

METHODS

A retrospective chart review was completed of all patients evaluated at a single center over 20 years who were found to have symptomatic LSCs requiring intervention. Only patients undergoing decompression without fusion were included in the analysis. Following this review, baseline characteristics were obtained as well as radiological information. A machine learning method (risk-calibrated supersparse linear integer model) was then used to create a risk stratification score to identify patients at high risk for symptomatic cyst recurrence requiring repeat surgical intervention. Following the creation of this model, a fivefold cross-validation was completed.

RESULTS

In total, 89 patients were identified who had complete radiological information. Of these 89 patients, 11 developed cyst recurrence requiring reoperation. The Lumbar Synovial Cyst Score was then created with an area under the curve of 0.83 and calibration error of 11.0%. Factors predictive of recurrence were found to include facet inclination angle > 45°, canal stenosis > 50%, T2 joint space hyperintensity, and presence of grade I spondylolisthesis. The probability of cyst recurrence ranged from < 5% for a score of 2 or less to > 88% for a score of 7.

CONCLUSIONS

The Lumbar Synovial Cyst Score model is a quick and accurate tool to assist in clinical decision-making in the treatment of LSCs.

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.

High Rate of Revision Surgery After Limited Decompression of Lumbar Facet Cysts

INTRODUCTION

The surgical treatment of lumbar facet cysts has long been debated. Some surgeons elect for limited decompression of such cysts while other surgeons elect for primary decompression and fusion over concerns for recurrence and instability. Previous studies have suggested the rate of revision surgery after facet cyst excision to be as low as 1%, whereas others have reported this rate to be markedly higher. In this study, we examined revision surgery rates and patient-reported outcomes and conducted a radiographic analysis to identify predictors of failure after limited decompression of lumbar facet cysts.

METHODS

A retrospective review of the electronic medical records of patients treated at our institution using the Current Procedural Terminology code 63267 before January 2018 was conducted. The primary outcome measure was revision surgery at the index level for recurrence or instability or a minimum 2-year follow-up without revision surgery. Secondary outcome measures include radiographic assessments of preoperative and postoperative spondylolisthesis and patient-reported outcome measures. Using preoperative MRI studies, an analysis of facet angles at the surgical level was conducted and the presence, location, and amount of facet fluid were calculated.

RESULTS

A total of 162 patients met inclusion criteria. Of these, 93 patients had a minimum 2-year follow-up. Of these, 19 had undergone a revision surgery at the index level for cyst recurrence or instability. The revision rate for this group was 20.4%. The median time to initial revision surgery was 2.2 years. The median time from index operation to last follow-up was 3.8 years. No differences were observed between the groups regarding the presence of preoperative spondylolisthesis, age, sex, body mass index, blood loss, or patient demographics. 60.2% of all procedures were done at the L4-5 level, but this level accounted for 73.7% of primary failures. A radiographic analysis showed facet angle >45° at L4-5 to be associated with risk of failure of primary decompression. The presence and absolute amount of fluid in the facets were not associated with risk of failure at the L4-5 level.

DISCUSSION

Our revision rate of 20.4% is higher than what is commonly reported in the literature. The radiographic analysis shows that at the L4-5 level, a facet angle of >45° is associated with failure of primary decompression.

Five-Year Outcomes After Decompression and Fusion Versus Decompression Alone in the Treatment of Lumbar Synovial Cysts

BACKGROUND

Spinal synovial cysts are acquired, fluid-filled lesions of the facet joint that most commonly occur in the lumbar spine. They are thought to arise from degenerative changes and to result from segmental instability. Although the treatment of these lesions has been studied, the long-term implications and effects of the different strategies for surgical intervention (i.e., decompression and fusion vs. decompression alone) have not yet been elucidated or established.

METHODS

Using an all-payer database with 53 million patient records (MARINER-53), patients with a diagnosis of lumbar synovial cysts were identified. Patients who had undergone lumbar fusion versus laminectomy were matched 1:1 using binomial and gaussian logistic regression models to evaluate the need for future lumbar surgery within 5 years after their index procedure.

RESULTS

No statistically significant differences were noted between the 5-year rates of subsequent intervention, additional laminectomy, or fusion among patients who had undergone index decompression and fusion (n = 51; 10.5%) versus decompression alone (n = 43; 8.8%; P = 0.39). Furthermore, no significant differences were found in the odds of intervention type after index decompression and fusion versus decompression alone (subsequent laminectomy: odds ratio, 0.59; 95% confidence interval, 0.32-1.09; subsequent fusion: odds ratio, 1.14; 95% confidence interval, 0.64-2.02).

CONCLUSIONS

Patient-specific factors and surgeon-patient-shared decision-making should be used when planning interventions for these lesions. However, synovial cysts might not require a fusion procedure for presumed instability. Further investigation is required, using randomized and prospective studies, to further evaluate the effective treatment of this entity.

Surgical management of facet cysts in the thoracic spine: Radiological manifestations and results of fenestration

BACKGROUND

Facet cysts in the thoracic spine are a rare cause of thoracic myelopathy. We aimed to investigate the clinical/radiological features and surgical results of these lesions.

METHODS

Nine thoracic facet cysts in eight patients (seven men, one woman) were diagnosed based on magnetic resonance imaging (MRI) and computed tomography (CT) with facet arthrography findings and surgically treated. The mean patient age was 71 (59-83) years. The cysts were distributed as follows: one each at T8-9 and T9-10, two each at T1-2 and T11-12, and three at T10-11. The mean follow-up period was 1.8 (1-5) years. Clinical and radiological features were retrospectively investigated, and surgical outcomes were evaluated according to modified Japanese Orthopaedic Association (JOA) scores for thoracic myelopathy (full score: 11).

RESULTS

Neurological examination revealed progressive thoracic transverse myelopathy in all patients with a mean disease duration of 1.2 months (2 weeks-2 months). MRI revealed a total of nine cysts across the eight patients: four in the median region and five in the paramedian portion of the spinal canal. CT revealed degeneration in all involved facet joints. All the cysts were in communication with the neighboring facet joint confirmed by CT facet arthrography. All patients underwent bilateral fenestration, and the cysts were resected with the ligamentum flavum. The mean preoperative and postoperative modified JOA scores were 4.5 and 8.8, respectively. The mean recovery rate was 67.5%. Differences in the degree of local kyphosis were 2° or less between before and after surgery. On histopathology, synovial lining cells were not noted in any case.

CONCLUSIONS

Decompression surgery is recommended for treating progressive myelopathy in patients with cystic lesions. Our study suggests that thoracic facet cyst resection with satisfactory surgical outcomes would be possible through fenestration.

Surgically managed symptomatic intraspinal lumbar facet synovial cyst outcome of surgical treatment with resection and instrumented posterolateral fusion, a case series

Background

There is controversy regarding the treatment of symptomatic synovial cysts, specifically, the need for a concomitant fusion when surgical resection of the synovial cysts is required. We present a retrospective review of a series of patients treated for symptomatic synovial cysts of the lumbar region during the last 20 years by a single surgeon, analyzing the current available literature.

Methods

Retrospective review. The same surgical technique was applied to all patients. Demographic, clinical, surgical data and synovial cyst recurrence rate were recorded. Postoperative results reported by patients were documented according to the McNab score.

Results

Sixty nine subjects, with mean follow-up of 7.4 years. 62% (43) were female, with a mean 57.8 years at the time of surgery. In 91.3% (63), the primary management was conservative for a minimum period of 3 months. All subjects underwent surgery due to the failure of conservative treatment. The segment most operated on was L4–L5 (63.77%). 91.3% (63) of the sample reported excellent and good and 6 subjects (8.6%) fair or poor results. There was no evidence of synovial cysts recurrence at the operated level.

Conclusion

In symptomatic synovial cysts, it seems that conservative treatment is only effective in a limited number of patients and in the short term. Thus, the recommendation of a surgical indication should proceed as soon as the conservative management fails to result in significant symptom relief. Based on our results, we recommend, together with the resection of the cyst, the instrumentation of the segment to avoid its recurrence and the management of axial pain.

Facet cysts in the subaxial cervical spine: Case series focused on radiological and histopathological findings with a scoping review

BACKGROUND

Facet cysts in the subaxial cervical spine are a relatively rare cause of neuropathy. This case series aimed to investigate the radiological and histopathological features and surgical results of these lesions, and provide possible mechanisms of cyst development.

METHODS

Thirteen subaxial cervical facet cysts in 12 patients were diagnosed on the basis of magnetic resonance imaging and computed tomography with facet arthrography. Surgical outcomes were evaluated according to the Japanese Orthopaedic Association scores for cervical myelopathy, or Tanaka's scores for cervical radiculopathy. These results were presented in combination with a scoping review of the literature.

RESULTS

Seven cysts were found in the posteromedial region, and six in the posterolateral portion of the spinal canal. Computed tomography revealed degeneration of all involved facet joints. All patients underwent decompression, and the mean recovery rates of Japanese Orthopaedic Association scores and Tanaka's scores were 57.1% and 87.5%, respectively. Histopathologically, all cysts were continuous with the degenerated ligamentum flavum. In the scoping review, the patients' mean age was 65.1 years. The cysts were distributed as follows: 3.6% at C2-3, 10.7% at C3-4, 14.3% at C4-5, 5.4% at C5-6, 7.1% at C6-7, and 58.9% at C7-T1. The presenting symptoms were myelopathy (49.4%) and radiculopathy (50.0%). Radiologically, 55% and 45% of the cysts were of the posteromedial and posterolateral types. Of the patients, 76.9% underwent decompression only, and 23.1% had concomitant fusion. Cyst recurrence was not observed in the mean follow-up period of 15.1 months.

CONCLUSIONS

The pathogenesis of cysts is closely related to degenerative changes in the facet joint and ligamentum flavum, and rupture in degenerated ligaments can develop into a cavity, which contributes to cyst formation. The scoping review suggests that cyst resection generally results in positive outcomes without recurrence in either decompression alone or concomitant fusion.

The Fate of Lumbar Facet Cyst After Indirect Decompression Using Oblique Lateral Interbody Fusion in Degenerative Spondylolisthesis

Favorable clinical outcomes have been reported for oblique lateral interbody fusion (OLIF) for various lumbar degenerative diseases. However, there is only limited evidence on the safety and effectiveness of OLIF in degenerative spondylolisthesis with lumbar facet cyst (LFC), and OLIF is often regarded as a relative contraindication for these patients. The authors prospectively enrolled patients who underwent a single-level OLIF for degenerative spondylolisthesis with LFC to evaluate the morphological changes of LFC and their clinical significance following OLIF. Twenty patients with a mean age of 69.6 years (range, 65-86 years) were enrolled. At 1 week postoperative, 5 (25%) patients had a residual cyst, whereas 15 (75%) patients had completely resolved cysts on magnetic resonance imaging (MRI). No patient had a residual cyst on the 1-year postoperative MRI. Patients with cyst resolution (n=15) on the 1-week postoperative MRI had a larger slip percentage difference on the preoperative dynamic radiograph when compared with patients with no cyst resolution (n=5) (4.7%±2.8% vs 1.3%±0.3%, P=.002). The group with cyst resolution also showed a greater expansion of facet fluid width following OLIF, although this was not statistically significant (1.2±0.7 mm vs 0.7±0.5 mm, P=.098). For both groups, all preoperative clinical scores showed a significant improvement at 1 year after OLIF, but there was no significant difference between the groups at all time points. Preliminary 1-year follow-up results from this prospective series suggest that OLIF can be a useful option for fusion surgery in LFC patients with apparent segmental instability. [Orthopedics. 2021;44(5):306-312.].

Axially Loaded Magnetic Resonance Imaging Identification of the Factors Associated with Low Back-Related Leg Pain

This retrospective observational study was conducted to identify factors associated with low back-related leg pain (LBLP) using axially loaded magnetic resonance imaging (AL-MRI). Ninety patients with low back pain (LBP) underwent AL-MRI of the lumbar spine. A visual analog scale and patient pain drawings were used to evaluate pain intensity and location and determine LBLP cases. The values of AL-MRI findings were analyzed using a logistic regression model with a binary dependent variable equal to one for low back-related leg pain and zero otherwise. Logistic regression results suggested that intervertebral joint effusion (odds ratio (OR) = 4.58; p = 0.035), atypical ligamenta flava (OR = 5.77; p = 0.003), and edema of the lumbar intervertebral joint (OR = 6.41; p = 0.003) were more likely to be present in LBLP patients. Advanced disc degeneration (p = 0.009) and synovial cysts (p = 0.004) were less frequently observed in LBLP cases. According to the AL-MRI examinations, the odds of having LBLP are more likely if facet effusion, abnormal ligamenta flava, and lumbar facet joint edema are present on imaging than if not. The assessment of lumbar spine morphology in axial loaded MRI adds value to the potential understanding of LBLP, but further longitudinal and loaded–unloaded comparative studies are required to determine the role of acute dynamic changes and instability in LBLP development.

Imaging in spinal posterior epidural space lesions: A pictorial essay

Spinal epidural space is a real anatomic space located outside the dura mater and within the spinal canal extending from foramen magnum to sacrum. Important contents of this space are epidural fat, spinal nerves, epidural veins and arteries. Due to close proximity of posterior epidural space to spinal cord and spinal nerves, the lesions present with symptoms of radiculopathy and/or myelopathy. In this pictorial essay, detailed anatomy of the posterior epidural space, pathologies affecting it along with imaging pearls to accurately diagnose them are discussed. Various pathologies affecting the posterior epidural space either arising from the space itself or occurring secondary to vertebral/intervertebral disc pathologies. Primary spinal bone tumors affecting the posterior epidural space have been excluded. The etiological spectrum affecting the posterior epidural space ranges from degenerative, infective, neoplastic - benign or malignant to miscellaneous pathologies. MRI is the modality of choice in evaluation of these lesions with CT scan mainly helpful in detecting calcification. Due to its excellent soft tissue contrast, Magnetic Resonance Imaging is extremely useful in assessing the pathologies of posterior epidural space, to know their entire extent, characterize them and along with clinical history and laboratory data, arrive at a specific diagnosis and guide the referring clinician. It is important to diagnose these lesions early so as to prevent permanent neurological complication.

Mid thoracic intra-spinal facet cyst with lumbar canal stenosis: a rare 'double crush'

INTRODUCTION

Intraspinal synovial cysts occurrence causing spinal canal occlusion are mostly seen in mobile segments of the spine (lumbar and cervical). An appearance of the cyst in thoracic spine is a relatively rare occurrence. We present an interesting case of 'double crush' caused by Lumbar canal stenosis with a mid-dorsal Facet cyst.

CASE PRESENTATION

A 67-year-old woman presented with complaints of back pain with neurogenic claudication with significant loss of touch sensation and motor power of MRC grade 3/5 in lower extremities bilaterally. However, patient was hyperreflexic with Babinski sign positive. She was unable to perform tandem walking test and complained of instability. MRI of lumbar spine revealed lumbar canal stenosis. However, in view of the UMN signs, an MRI of the dorsal spine was done. It revealed an extradural, well-delineated lesion along the dorsal aspect of spine at T6-7 level. Thus the patient had a 'double crush' due to the FC along with lumbar canal stenosis.

CLINICAL FINDINGS CORRELATED WITH THE IMAGING

Two teams simultaneously operated the 2 pathologies and T6-7 laminectomy along with left sided TLIF at L4-5 level was performed. Presently she is asymptomatic for back pain, claudication distance has improved to 800 m.

CONCLUSION

Our case reiterates the importance of thorough clinical examination to avoid missing a diagnosis. Our case is the first in literature to report a 'double crush' due to a proximal dorsal FC and distal LCS. Both the pathologies were tackled in a single setting by two operating teams with a good functional outcome.

A Practical Approach to Spine Magnetic Resonance Imaging

Magnetic resonance imaging (MRI) plays an important role in the evaluation of patients with spine disorders, providing excellent evaluation of both normal and pathologic anatomy. Interpreting MRI findings can be difficult as anatomic abnormalities may not correlate with clinical symptoms and MRI may show abnormal findings in asymptomatic individuals. Using a systematic approach to interpreting a spinal MRI can help to achieve an accurate diagnosis and guide therapeutic decision-making, surgical intervention, and treatment monitoring.

Comparison of Decompression versus Decompression and Fusion for Lumbar Synovial Cysts and Predictive Factors for Cyst Recurrence

BACKGROUND

The management of lumbar synovial cysts (LSC) has been a controversial topic for many years. Whereas many authors label LSC as markers of instability and thus necessitating fusion, others suggest that decompression alone without fusion is a viable initial treatment option. Our objective was to clarify outcomes in patients undergoing decompression alone and decompression with fusion for symptomatic LSC and identify factors for cyst recurrence.

METHODS

A retrospective case series was performed of all patients undergoing initial treatment for LSC at a single institution ranging from January 1999 to February 2020. Surgical treatment included either decompression with cystectomy or decompression with cystectomy and a fusion procedure. Preoperative symptoms were collected and included radicular pain, motor deficits, sensory deficits, or bowel/bladder changes. Radiographic data were calculated individually and confirmed with radiology reports. Categorical variables were assessed using χ² analysis and continuous variables were assessed with the 2-sample t test.

RESULTS

In total, 161 patients were identified as presenting with symptomatic LSC. Of these, 104 patients underwent decompression alone versus 57 who underwent decompression and fusion. In the decompression group 11 patients required reoperation at the level of the cyst compared with none in those undergoing fusion as their initial procedure (10.5% vs. 0%, P = 0.012). On subgroup analysis of those undergoing decompression as their initial procedure, patients with cyst recurrence demonstrated a statistically significant greater coronal facet inclination angle compared with those without cyst recurrence (52.4° vs. 40.6°, P = 0.02).

CONCLUSIONS

Decompression alone is a reasonable choice for the initial management of LSC, although it does carry a significant risk of same-level reoperation due to cyst recurrence and spondylolisthesis. Preoperative coronal facet inclination angle may be a useful measurement in predicting cyst recurrence following decompression.

Retro-odontoid Pseudotumor: Two Cases of Intradural Ganglion Cysts Arising From the Odontoid Process with Syringobulbia

BACKGROUND

Ganglion cysts mostly occur in the knuckles and wrists, but they rarely present in the odontoid process and can cause neurological symptoms by compressing the spinal cord. They are mostly localized in the epidural space, but may very rarely appear in the intradural space. There are no reports of cases of intradural ganglion cyst involving syringobulbia.

CASE DESCRIPTION

We report the presentation and management of 2 cases of an intradural ganglion cyst of the odontoid process. Several treatment options for ganglion cysts of the odontoid process have been reported, such as rest and use of a neck collar, posterior decompression and fusion, and transoral anterior decompression. Because our 2 cases progressed rapidly and had severe neurological symptoms, surgical treatment was performed for rapid decompression and definitive pathological diagnosis. The mass was resected as much as possible using the lateral occipital fossa approach, and the operation was completed without dissection of the brain stem or manipulation of the syringobulbia. Postoperatively, neurological symptoms promptly improved, and the syringobulbia reduced.

CONCLUSIONS

For intradural ganglion cysts with syringobulbia, we suggest relief of the compression by resection of the mass and treatment of the syringobulbia in 2 stages, if necessary, to avoid the risk of damage to the brainstem.

An Unusual Case of Radicular Pain Caused by Bilateral Lumbar Synovial Cyst: A Case Report and Review of the Literature

Introduction

Spinal synovial cysts (SSCs) constitute an uncommon degenerative lesion of the spine. They are usually asymptomatic but they may also cause symptoms of variable severity. SSCs are benign growths adjoining the facet joints that may induce low back pain, lumbar radiculopathy, and neurological deficit. There are different treatment options that range from conservative management to interventions like image-guided epidural steroid injection or direct cyst puncture and finally to open or endoscopic spinal canal decompression and spinal bone fusion with/without instrumentation. A discussion of current management options for this unusual disease is presented. Material and Methods. A 52-year-old female patient presented with low back pain and left leg pain. Plain radiography demonstrated instability at the L4-L5 level. Magnetic resonance images (MRIs) revealed a bilateral cystic lesion at the L4-L5 level with associated instability and degenerative disc disease at the level L5-S1. Initially, conservative treatment was performed by aspiration of the left cyst and infiltration with corticosteroids with improvement of the pain for 1 year. After this period, the radicular and the low back pain reoccurred.

Results

Following leg pain recurrence, a hybrid L4-S1 fusion was performed. After surgery, there was clinical improvement and six months later, the patient returned to daily activities. The radiological study after five-year follow-up shows adequate implant position, without signs of loosening, compatible with solid fusion.

Conclusion

After reviewing the literature, the optimal management for patients with symptomatic lumbar synovial cyst must be very individualized, which is essential to achieve a favorable outcome.

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.

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.

New classification of facet joint synovial cysts

PURPOSE

Facet cysts develop due to degeneration of the zygapophyseal joints and can lead to radiculopathy and neurogenic claudication. Various surgical options are available for facet cyst excision. The aim was to facilitate surgical treatment of lumbar facet cysts based on a new classification.

METHODS

We retrospectively analyzed all patients of the last 10 years in whom a facet cyst was surgically removed (ipsilateral laminotomy, contralateral laminotomy, and segmental fusion). Several radiological parameters were analyzed and correlated with the patients' outcome (residual symptoms, perioperative complications, need for re-operation, need for secondary fusion, facet cyst recurrence).

RESULTS

One hundred eleven patients (55 women; median age 64 years) could be identified. Thirty-three (48%) of 69 cases, for which MRI data were available, were classified as medial facet cyst (compressing the spinal canal), 6 facet cysts were localized intraforaminal (9%) and 30 cases (43%) mediolateral (combination of both). The contralateral approach had the lowest rate for revision surgery (7.5%, p = .038) and the lowest prevalence of residual complaints (7.5%, p = .109). A spondylolisthesis and a higher/steeper angle of the facet joints were associated with poorer patient outcome.

CONCLUSIONS

Lateral facet joint cysts are best resected by a contralateral approach offering the best outcome while medial cysts are suitable for removal by an ipsilateral laminotomy. The approach of mediolateral cysts can be determined by the width of the lamina and the angle of the joint. Segmental fusion should be considered in cases with detected spondylolisthesis and/or steep facet joints.

The Variability of Lumbar Facet Joint Synovial Cyst Recurrence Requiring Revision Surgery After Decompression-only and Decompression/Fusion

STUDY DESIGN

This is a retrospective study.

OBJECTIVE

The objective of this study was to evaluate lumbar spine synovial cyst recurrence rates of decompression-alone versus decompression/fusion procedures.

BACKGROUND

Improvements in imaging modalities allow for increased diagnosis and surgical treatment of symptomatic spinal juxtafacet synovial cysts. Conservative management may be used as a first-line management strategy, however rarely provides durable, effective relief of symptoms. Surgical treatment of spinal synovial cysts ranges from decompression and cyst excision to decompression with fusion procedures. Decompression procedures alone have a higher risk of recurrence of spinal synovial cysts.

METHODS

We retrospectively reviewed 87 patients undergoing surgical treatment of lumbar spinal juxtafacet synovial cysts as a single institution over 20 years. Surgical treatment consisted of either decompression versus decompression/fusion procedures. Preoperative symptoms included back pain, radiculopathy, motor deficits, or sensory deficits. The incidence of recurrence of spinal synovial cysts at the same-site or differing sites was compared between 2 categories of surgical treatment. Revision surgical procedure rates were also evaluated.

RESULTS

A total of 55 (63%) patients were treated with an index decompression-only procedure for the lumbar spinal synovial cyst compared with 32 (37%) patients treated with an index decompression and fusion procedure. Fifty-eight (68%) of the lumbar spinal cysts occurred at the L4-L5 level. There were 10 (11.5%) spinal synovial cyst recurrences in the decompression-only group, and 0 recurrences in the decompression/fusion group. Revision decompression procedures were performed in 4 of the 10 (4.6%) recurrences, and 6 of 10 (6.9%) recurrences had subsequent decompression and fusion surgery. The mean time to recurrence was 23.9±17.3 months. The mean length of follow-up was 65.1±48.6 months. Both recurrence and nonrecurrence cohorts had significant symptomatic improvement using Odom criteria.

CONCLUSIONS

Decompression and cyst excision was the more common surgical treatment of lumbar spinal synovial cysts compared with decompression/fusion procedure in our study. The rate of synovial cyst recurrence and revision surgery in patients undergoing index decompression was relatively low and comparable to current literature. Symptomatic improvement of patients undergoing decompression versus decompression/fusion was similar in our study. Although the fusion may be required for the extent of pathology or coexisting instability, decompression and excision of spinal synovial cysts provide durable, effective treatment with a known, appropriate risk of recurrence and subsequent revision surgery.

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.

LUMBAR SPINE SYNOVIAL CYST: A CASE SERIES REPORT AND REVIEW OF SURGICAL STRATEGIES

Lumbar spine synovial cysts are benign growths adjoining the facet joints that may induce low back pain, lumbar radiculopathy and neurological deficit. However, they are not well defined concerning their origin, cause and pathology, as well as available treatment strategies. The scope of different surgical procedures includes image-guided epidural steroid injection, direct cyst puncture by percutaneous epidural needle, spinal canal decompression and cyst resection, and spinal bone fusion with/without instrumentation. Hereby, we report institutional experience and discuss surgical strategies of lumbar spine synovial cyst treatment. Presenting symptoms, imaging findings and outcomes were retrospectively analyzed in 15 patients with lumbar spine synovial cyst, operated on during a one-year period. The leading presenting symptom was lumbar radicular pain, while the most commonly involved vertebral level was L5-S1. In a great majority of patients, a single-level interlaminectomy and cyst resection were performed. Most patients recovered without postoperative neurological and functional deficit, as well as surgery-related complications. No poor outcome was noticed in our series. Concerning our results and literature review, the optimal management for patients with symptomatic lumbar synovial cyst has to be highly personalized, which is essential to achieve a favorable outcome. Nonetheless, the best treatment strategy has yet to be affirmed.

[Lumbar synovial cysts: literature review and original long-term results after microsurgical resection]

BACKGROUND

Intraspinal lumbar vertebral joint cysts are an unusual cause of nerve root compression symptoms and do not differ clinically from the symptoms of a herniated disc.

PATHOGENESIS

The cysts originate from the small vertebral joints and, depending on their size, compress the nerval structures. The affected vertebral joints typically show activated arthritic circumstances, which are associated with degenerative spondylolisthesis in about 50% of cases. In the majority of cases, MRT and CT can be used for diagnostic purposes. The exact etiology has not been fully clarified; various factors such as activated arthritis of the vertebral joints appear to be the major cause.

TREATMENT

Treatment options include conservative, semi-invasive and surgical therapy. Conservative and semi-invasive treatment methods lead to temporary improvement. The result of surgical treatment, however, is excellent in a complete resection of synovial cysts. In In rare cases, an initial fusion is necessary in rare cases.

[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.

Resolution of Symptomatic Lumbar Synovial Cyst After Traumatic Event

BACKGROUND

Synovial cysts are most commonly found in the lumbar spine and are associated with low back pain and radiculopathy. Frequent use of imaging modalities has led to an increase in intraspinal synovial cyst identification. Treatment typically ranges from conservative measures to surgical decompression, but spontaneous resolution has previously been reported. Here, we present the first report of symptomatic lumbar synovial cyst resolution after a traumatic fall.

CASE DESCRIPTION

We present a case of a symptomatic synovial cyst between the fourth (L4) and fifth (L5) lumbar vertebrae identified on magnetic resonance imaging (MRI). The patient presented with right paramedian back pain and right-sided L5 radiculopathy. She underwent unsuccessful trials of antiinflammatory agents and physical therapy. Less than 1 year since initial diagnosis, the patient sustained a mechanic fall followed by resolution of prior symptoms. A subsequent lumbar MRI revealed complete resolution of the intraspinal synovial cyst.

CONCLUSIONS

The diagnosis of synovial cysts are increasing in frequency due to their ease of identification with computed tomography and MRI. For cases of refractory pain and/or neurologic deficits, surgical decompression is usually necessary. In rare instances, synovial cysts may spontaneously regress or resolve secondary to other events. This is the first description of resolution after a traumatic fall. Due to limited data on this topic, this report may provide additional insight into the pathophysiology of synovial cyst formation and resolution.

Age Is a Risk Factor for Postoperative Complications Following Excisional Laminectomy for Intradural Extramedullary Spinal Tumors

STUDY DESIGN

Retrospective analysis.

OBJECTIVE

The incidence of intradural extramedullary (IDEM) spinal tumors is increasing. Excisional laminectomy for removal and decompression is the standard of care, but complications associated with patient age are unreported in the literature. Our objective is to identify if age is a risk factor for postoperative complications after excisional laminectomy of IDEM spinal tumors.

METHODS

A retrospective analysis was performed on the 2011 to 2014 ACS-NSQIP (American College of Surgeons National Surgical Quality Improvement Program) database for patients undergoing excisional laminectomy of IDEM spinal tumors. Age groups were determined by interquartile analysis. Chi-squared tests, t tests, and multivariate logistic regression models were employed to identify independent risk factors. Institutional review board approval was not needed.

RESULTS

A total of 1368 patients met the inclusion criteria for the study. Group 1 (age ≤ 44) contained 372 patients, group 2 (age 45-54) contained 314 patients, group 3 (age 55-66) contained 364 patients, and group 4 (age > 66) contained 318 patients. The univariate analysis showed that mortality and unplanned readmission were highest among patients in group 4 (1.26%, P = .011, and 10.00%, P = .039, respectively). Postoperative wound complications were highest among patients in group 1 (2.15%, P = .009), and postoperative venous thromboembolism and cardiac complications were highest among patients in group 3 (4.4%, P = .007, and 1.10%, P = .032, respectively). Multivariate logistic regression revealed that elderly age was an independent risk factor for postoperative venous thromboembolism (group 3 vs group 1; odds ratio = 6.739, confidence interval = 1.522-29.831, P = .012).

CONCLUSIONS

This analysis revealed that increased age is an independent risk factor for postoperative venous thromboembolism in patients undergoing excisional laminectomy for IDEM spinal tumors.

Interlaminar stabilization and decompression for the treatment of bilateral juxtafacet cysts: Case report and literature review

•

Lumbar juxtafacet cysts are typically treated by resection alone or resection combined with posterior instrumentation.

•

Resection with instrumentation is associated with a lower rate of recurrence but also with increased cost and morbidity.

•

We present a case of bilateral juxtafacet cysts causing neurogenic claudication treated with decompression and interlaminar stabilization.

•

Complete symptom resolution was sustained at one-year follow-up.

•

Decompression followed by interlaminar stabilization may be a reasonable alternative for some patients.

Introduction

Lumbar juxtafacet cysts (JFCs) are a common cause of lumbar radiculopathy which tend to occur in areas of increased facet mobility. While resection alone is a possible treatment, recent publications suggest that laminectomy alone for JFCs may not yield as favorable an outcome as laminotomies reinforced with posterior dynamic hardware. The Coflex^® is a novel interlaminar stabilization device that has been shown to achieve comparable results to rigid fusion in the management of lumbar stenosis in patients with no more than grade one anterolisthesis, and superior performance compared to laminectomy alone when a combined outcome score was used. We describe the combined use of dynamic posterior element fusion with primary cyst resection in the management of bilateral JFCs.

Presentation of case

A 71-year-old man who developed a progressive left L4 radiculopathy along with new urinary incontinence was found to have bilateral L3/4 JFCs causing significant lumbar stenosis and neurogenic claudication. After treatment with primary cyst resection and interlaminar stabilization, the patient experienced complete symptom resolution and was discharged to inpatient-rehabilitation on post-operative day 1.

Discussion

While current recommendations for the management of juxtafacet cysts causing progressive neurologic symptoms include surgical cyst removal and lumbar decompression with or without fusion, the role of dynamic interlaminar stabilization has not been explored.

Conclusion

Direct decompression followed by interlaminar stabilization may represent an alternative for patients to simultaneously benefit from a decompression of their juxtafacet cysts while affording posterior element reconstruction.

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.

Age Stratification of 30-Day Postoperative Outcomes Following Excisional Laminectomy for Extradural Cervical and Thoracic Tumors

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To evaluate age as an independent predictive factor for perioperative morbidity and mortality in patients undergoing surgical decompression for metastatic cervical and thoracic spinal tumors using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database from 2011 to 2014.

METHODS

We identified 1673 adult patients undergoing excisional laminectomy of cervical and thoracic extradural tumors. Patients were stratified into quartiles based on age, with Q1 including patients aged 18 to 49 years, Q2 including patients aged 50 to 60 years, Q3 including patients aged 61 to 69 years, and Q4 including patients ≥70 years. Univariate and multivariate regression analyses were performed to examine the association between age and 30-day perioperative morbidity and mortality.

RESULTS

Age was an independent risk factor for 30-day venous thromboembolism (VTE) and reoperation. Patients in Q3 for age had nearly a 4 times increased risk of VTE than patients in Q1 (odds ratio [OR] 3.97; 95% CI 1.91-8.25; P < .001). However, there was no significant difference in VTE between patients in Q4 and Q1 (P = .069). Patients in Q2 (OR 1.99; 95% CI 1.06-3.74; P = .032) and Q4 (OR 2.18; 95% CI 1.06-4.52; P = .036) for age had a 2 times increased risk of reoperation compared with patients in Q1.

CONCLUSIONS

Age was an independent predictive factor for perioperative VTE and reoperation, but there was no clear age-dependent relationship between increasing age and the risk of these perioperative complications.

NeuroSpine Surgery Research Group (NSURG) Classification System for Grading Lumbar Synovial Cysts

To classify facet joint cysts (FJC) which will assist in identification of patient groups to best fit with a particular intervention. Sagittal T₂ -weighted magnetic resonance images (MRI) of these patients are used to measure cyst size, while axial T₂ -weighted MRI are used to determine the percentage of the vertebral canal occupied by the cyst. The degree of spondylolisthesis is also measured through standing X-rays or sagittal MRI. The proposed grading system is as follows. Grade I includes cysts that occupy less than 25% of the canal diameter that usually present with unilateral radiculopathy. Grade II includes cysts that occupy less than 50% of the canal diameter and may present with radiculopathy, with or without claudicant symptoms. Grade III cysts may present with radiculopathy and claudication with bilateral leg symptoms, along with facetogenic pain symptoms. Grades IV and V include potential instability as defined by greater than 15% spondylolisthesis in addition to either less than or greater than 50% canal stenosis. With higher grade cysts, presentation may include: facetogenic back pain, radiculopathy and claudicant pain in variable degrees of severity. The optimal classification system grades FJC from I to V on the basis of canal compression and degree of spondylolisthesis. Prospective studies are required to confirm the validity of this grading scale for long-term use.

[CME: Lumbar spinal stenosis]

Spinal stenosis can be found in up to 80 % of individuals aged over 70 years. However, about 20 % of asymptomatic individuals demonstrate signs of spinal stenosis on MRI. The pathomechanism of central spinal stenosis is predominantly related to degenerative changes. Those eventually result in a progressive compression of the cauda equina. Patients who exhibit mild to moderate symptoms should undergo multimodal conservative treatment, such as patient education, pain medication, physiotherapy and epidural injections. Surgery should be evaluated in patients with severe symptoms, especially if conservative treatment fails after 3–6 months of trial. Clinically relevant motoric deficits or symptoms of cauda equina syndrome remain absolute indications for surgery.

Development of Bilateral Facet Cysts Causing Recurrent Symptoms After Decompression and the Placement of an Intralaminar Implant: A Case Report

CASE

We report the development of bilateral symptomatic facet joint cysts in a 78-year-old man who had been treated with decompression and placement of a coflex device (Paradigm Spine) at L3-L4 and L4-L5. Preoperative imaging clearly demonstrated fluid in the facet joints without cysts. He underwent standard surgical treatment, but developed symptomatic facet joint cysts at 4 months postoperatively. The patient was treated with a revision decompression and replacement of the devices; there were no issues at the 32-month follow-up.

CONCLUSION

While the coflex device has possible long-term biomechanical advantages, vigilance with adherence to appropriate decompression surgical technique is necessary.

Comparison of Decompression With and Without Fusion for Patients With Synovial Facet Cysts

STUDY DESIGN

This is a retrospective study.

OBJECTIVE

To compare (1) recurrence of radiculopathy and (2) back pain after decompression with and without fusion for patients with a symptomatic synovial cyst.

BACKGROUND

Previous work described favorable outcomes following cyst excision with and without fusion. Because of the association of facet cysts with spinal instability it is hypothesized that a decompression with fusion will lead to better outcomes. However, previous studies present contradicting results.

METHODS

We included 314 consecutive patients that underwent operative treatment for a facet cyst between 2003 and 2013 at 2 tertiary spine referral centers: 224 (71%) underwent decompression without fusion (35% spondylolisthesis), 90 (29%) underwent decompression with fusion (63% spondylolisthesis). Baseline data were compared between the groups. Bivariate log-rank analysis was used to compare outcomes between groups, followed by multivariable Cox regression analysis accounting for differences in baseline characteristics.

RESULTS

Patients undergoing decompression with fusion presented with a higher incidence of back pain (P=0.004) and spondylolisthesis (P<0.001), had more often bilateral decompressions (P<0.001), more facetectomies (P<0.001), and more levels of decompression (P=0.004) than those who underwent decompression alone. We found a difference in recurrence of radiculopathy (no fusion: 25% vs. fusion: 9.4%, P=0.029) in bivariate analysis. However, this difference did not hold when accounting for confounders (hazard ratio, 0.50, 95% confidence interval, 0.19-1.31, P=0.16). There was no difference in recurrence of back pain in bivariate (no fusion: 29% vs. fusion: 22%, P=0.51) and multivariable analysis (hazard ratio 0.51, 95% confidence interval, 0.23-1.14, P=0.10).

CONCLUSIONS

We found, with the numbers evaluated, no difference in recurrence of radiculopathy or back pain between patients undergoing decompression with or without fusion after accounting for confounders. The decision for fusion should be considered in light of the extent of decompression and the existence of other pathology.

LEVEL OF EVIDENCE

Level III-therapeutic study.

Long-Term Effectiveness of Direct CT-Guided Aspiration and Fenestration of Symptomatic Lumbar Facet Synovial Cysts

BACKGROUND AND PURPOSE

Lumbar facet synovial cysts are commonly seen in facet degenerative arthropathy and may be symptomatic when narrowing the spinal canal or compressing nerve roots. The purpose of this study was to analyze the safety, effectiveness, and long-term outcomes of direct CT-guided lumbar facet synovial cyst aspiration and fenestration for symptom relief and for obviating an operation.

MATERIALS AND METHODS

We retrospectively reviewed the medical records and imaging studies of 64 consecutive patients between 2006 and 2016 who underwent 85 CT-guided lumbar facet synovial cyst fenestration procedures in our department. We recorded patient demographics, lumbar facet synovial cyst imaging characteristics, presenting symptoms, change in symptoms after the procedure, and whether they underwent a subsequent operation. We also assessed long-term outcomes from the medical records and via follow-up telephone surveys with patients.

RESULTS

Direct CT-guided lumbar facet synovial cyst puncture was technically successful in 98% of procedures. At first postprocedural follow-up, 86% of patients had a complete or partial symptomatic response. During a mean follow-up of 49 months, 56% of patients had partial or complete long-term relief without the need for an operation; 44% of patients underwent an operation. Patients with calcified, thick-rimmed, or low T2 signal intensity cysts were less likely to respond to the procedure and more likely to need an operation.

CONCLUSIONS

CT-guided direct lumbar facet synovial cyst aspiration and fenestration procedures are safe, effective, and minimally invasive for symptomatic treatment of lumbar synovial facet cysts. This procedure obviates an operation in a substantial number of patients, even at long-term follow-up, and should be considered before surgical intervention.

Should We Label All Synovial Cysts as Unstable?

STUDY DESIGN

Retrospective study.

OBJECTIVE

To analyze the various anatomical parameters that influence segmental stability in patients suffering from lumbar intra spinal cysts (LISCs) and to determine the outcome of microscopic unilateral laminotomy and cystectomy.

METHODS

All patients that were surgically managed for a LISC between 2007 and 2013 with more than 3 years of follow-up were reviewed. Those without associated instability were evaluated for segmental mobility, segmental angulation, facet inclination, stage of disc degeneration, and level of involvement on MRI and dynamic radiographs. Outcomes of unilateral laminotomy and cystectomy were evaluated using VAS (Visual Analogue Score), ODI (Oswestry Disability Index), and Macnabs criteria. Dynamic radiographs were performed in all cases pre- and postoperatively and at the last follow-up.

RESULTS

Thirty patients were operated for a LISC between 2007 and 2013. The levels involved were L4-5(23), L3-4(4) and L5-S1(3). The mean facet angle was 42.6 (± 6.1) degrees. The stage of disc degeneration was scattered haphazardly across all the cases (Gr 2[17]; Gr 3[1]; Gr 4[8]; Gr 5[4]). VAS and ODI scores improved significantly in all patients. Mean follow-up was 46.5 months (36-96 months). No patient developed postoperative instability at the last follow-up.

CONCLUSIONS

The coronal inclination of the facet joints, absence of radiological instability, and poor co-relation with stages of disc degeneration suggests the presence of adequate residual stability. In this study, stand-alone decompression for LISCs without instability had well sustained good/excellent outcomes. Fusion is recommended for LISCs with associated instability.

Thoracic Synovial Cyst at the Th2-3 Level Causing Myelopathy

Intraspinal synovial cyst is a rare cause of myelopathy. These cysts present most often in the lumbar and cervical parts of the spine but are more infrequent in the thoracic spine. We present a case of a 73-year-old man with an intraspinal, extradural synovial cyst at the Th2-3 level causing paraesthesia and weakness in the legs. A laminectomy and excision of the cyst were performed and the patient recovered fully. In the thoracic spine, synovial cysts are almost exclusively found in the lower part. Laminectomy, with excision, is the treatment of choice, although steroid injections have been described.