Factors associated with recurrent back pain and cyst recurrence after surgical resection of one hundred ninety-five spinal synovial cysts: analysis of one hundred sixty-seven consecutive cases

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.

The effect of integrative Korean medicine treatment on symptomatic lumbar facet joint cysts: A case series

OBJECTIVE

The optimal treatment for facet joint cysts (FJCs) has remained controversial. Despite a higher success rate than the conservative option, surgical treatments may pose risks of postoperative complications and comorbidities may make the surgical approach difficult. Thus, this study reports four cases of pain amelioration and resorption of FJCs through noninvasive integrative Korean Medicine treatment.

METHODS

For intervention, four patients with symptomatic FJCs underwent integrative Korean medicine treatment with acupuncture, herbal medicine, pharmacopuncture, and Chuna manual therapy; after completion of the series of treatment sessions, patients were re-examined with magnetic resonance imaging (MRI).

RESULTS

Pain disappeared within 2 months for all four patients; the amelioration of pain was sustained for more than 6 months. Furthermore, the disappearance of FJCs was confirmed by MRI after a certain period from the time of pain disappearance.

CONCLUSIONS

This study reported the effectiveness of non-invasive, integrative Korean medicine treatment for patients with FJCs; this method shows promise as a conservative treatment option for patients with FJCs.

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.

A rare gas-containing lumbar synovial cyst treated by percutaneous transforaminal endoscopic cystectomy: A case report and literature review

Spinal synovial cysts are rare entities for which standard surgical strategies are inconsistent. Here, we present an uncommon intraspinal gas-containing synovial cyst treated by percutaneous transforaminal endoscopic cystectomy. A 52-year-old man presented with radicular pain and intermittent claudication that had persisted for one month. Computed tomography revealed an intraspinal cystic lesion anteromedial to the left L4-L5 articular joint and the center of the lesion manifested gas contents. A transforaminal endoscopic procedure was performed and confirmed as a safe and minimally invasive technique for gas-containing lumbar synovial cysts. It provides a valuable substitution and supplementation to open surgery.

Lumbar Synovial Cysts-Should You Fuse or Not?

BACKGROUND

Spinal synovial cysts are lesions that most commonly occur in the lumbar region. The need for an instrumented spinal fusion in addition to lumbar decompression with removal of the synovial cyst is unknown.

OBJECTIVE

To test the hypothesis that select patients who underwent decompression with instrumented fusion for lumbar synovial cysts would be less likely to have subsequent surgery (SS) in a 2-year period than patients treated with laminectomy alone.

METHODS

This retrospective cohort study was performed using IBM MarketScan Commercial Claims and Encounters Database. Patients who had a lumbar synovial cyst diagnosis and laminectomy surgery with or without fusion surgery were included in this study. Patients were tracked for SS 2 years after surgery. Laminectomy patients were propensity score-matched to laminectomy with fusion (LF) patients using a 2:1 ratio. The log-rank test and Cox regression were used to compare the cumulative incidence of SS between groups.

RESULTS

There were 7664 and 1631 patients treated with laminectomy and LF before matching. After matching, there were 2212 laminectomy and 1631 LF patients and patient characteristics were balanced. The 2-year incidence of recurrent SS was 3.1% ([CI]: 2.2%, 4.0%) and 1.7% (95% CI: 0.9%, 2.5%) laminectomy and LF, respectively. Compared with laminectomy, LF had a statistically significant lower risk of recurrent SS (hazard ratio: 0.56 [95% CI: 0.32-0.97]; P -value: .04).

CONCLUSION

All patients who had concomitant lumbar fusion showed decreased chance of having a cyst- or noncyst-related recurrence SS when compared with all patients undergoing laminectomy alone, regardless of diagnosis at the time of SS.

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.

Bilateral Lumbar Facet Synovial Cysts as a Cause of Radiculopathy

Remarkable advancements in endoscopic spinal surgery have led to successful outcomes comparable to those of conventional open surgery with the benefits of less traumatization and postoperative spinal instability. Bilateral lumbar facet cysts are rarely found in the spinal canal. We report a rare case of L4–L5 bilateral lumbar facet cysts compressing the nerve root in a patient who presented with L5 radiculopathy. Endoscopic decompression and removal of the cysts without fusion were performed. Histopathology revealed synovial cysts. Postoperatively, the patient showed a total resolution of symptoms with sustained benefits at the final evaluation. No recurrence of pain and no further segmental instability were observed at the 1-year follow-up.

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.

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.

Neuropathic Pain due to Compression of Cervical Medial Branch by Cervical Juxtafacet Cyst: A Case Report

In the current report, we describe an interesting case of cervical juxtafacet that developed outside the intervertebral foramen, compressing the cervical medial branch and causing neuropathic pain in the posterior inferior neck pain. A 61-year-old woman visited a local pain clinic due to neuropathic pain with a tingling and burning nature (numeric rating scale [NRS]: 5 out of 10) on the left posterior inferior neck area for 4 months. Paresthesia was observed in the left posterior inferior neck area. On cervical radiography, segmental instability was observed at the C3-4 and C4-5 levels. Moreover, on the magnetic resonance imaging (MRI) of the cervical spine, a cyst (size: 1.3 cm × 0.7 cm × 1 cm) was outside the intervertebral foramen, contacting the left C4-5 facet joint and left C5 articular pillar. We thought that compression of the left C5 medial branch by the cyst could cause the patient's pain. We conducted computed tomography (CT)-guided percutaneous needle aspiration of a cervical juxtafacet cyst. An 18-gauge needle was advanced under the guidance of CT into the largest portion of the cyst through a posterolateral oblique approach. Gelatinous mucoid fluid (approximately 0.5 cc) was aspirated. Immediately after the aspiration, 80% of the patient's pain was disappeared, and dysesthesia was completely disappeared. At the 1-, 3-, and 6-month follow-ups, the patient reported slight pain (NRS: 1) on the left posterior inferior neck. Cervical juxtafacet cysts can develop outside of the intervertebral foramen and spinal canal. Percutaneous needle aspiration can be a useful therapeutic tool for the treatment of such cysts.

Patient-Reported Outcomes for Lumbar Fusion in Patients with Previously Treated Cervical Myelopathy

BACKGROUND

Patients with a history of surgically treated cervical myelopathy and lumbar pathology requiring fusion present complex challenges, and literature describing patient-reported outcomes in this cohort beyond patients with tandem spinal stenosis is sparse. This has led to unclear guidelines in the literature. We present the first dataset comparing patient-reported outcomes for lumbar fusion in patients with isolated lumbar pathology versus patients with a history of surgically treated cervical myelopathy.

METHODS

In this retrospective cohort study of a prospectively collected lumbar fusion database, variables of interest included demographics, comorbidities, type and levels of fusion, Oswestry Disability Index (ODI), and minimal clinically important difference.

RESULTS

Of 325 patients identified, 309 met inclusion criteria. Of these, 29 patients had previous cervical surgery to address cervical myelopathy. Median time between cervical and lumbar surgery was 4.0 years (range, 0.3-19.7). There was no statistical difference in preoperative ODI score (24.8 vs. 25.6, P = 0.687), 6-month postoperative ODI score (17.3 vs. 18.7, P = 0.459), change in ODI score (7.5 vs. 6.9, P = 0.673), or minimal clinically important difference for ODI score (62.1% vs. 58.6%, P = 0.710) in patients who had undergone cervical surgery versus patients who had not.

CONCLUSIONS

Patients with a history of previously treated cervical myelopathy have a similar rate of clinically relevant improvement after lumbar fusion compared with patients without such history. As such, these patients appear to benefit from lumbar fusion surgery to the same degree as patients without a history of surgically treated cervical myelopathy.

Acute development of spinal lumbar synovial facet cyst within 1 week after lumbar decompression: illustrative case

BACKGROUND

Synovial facet cysts can sometimes develop in patients with lumbar spinal stenosis after decompressive laminectomy. The etiology of spinal lumbar synovial cysts is still unclear, but their formation is associated with underlying spinal instability, facet joint arthropathy, and degenerative spondylolisthesis.

OBSERVATIONS

A 61-year-old-male patient presented with neurogenic claudication due to lumbar spinal stenosis. Radiographic studies showed grade I spondylolisthesis and radiological predictors of delayed spinal instability. He underwent lumbar decompression and shortly thereafter developed spinal instability and recurrent symptoms, with formation of a new spinal lumbar synovial facet cyst. He required revisional decompression, cyst excision, and posterolateral spinal fusion for definitive treatment.

LESSONS

The literature reports postoperative spinal instability in up to one-third of patients with lumbar spinal stenosis and stable degenerative spondylolisthesis who undergo decompressive laminectomy. Close radiographic monitoring and early advanced imaging may be prudent in this patient population if they develop new postoperative neurological symptoms and show radiographic predictors of instability on preoperative imaging. Posterolateral spinal fusion with instrumentation should be considered in addition to lumbar decompression in this select group of patients who demonstrate radiographic predictors of delayed spinal instability if they are medically capable of tolerating a spinal fusion procedure.

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.].

Classification and Reliability of Lumbar Facet Cysts Grading Scales

BACKGROUND

The presence of symptomatic lumbar facet cysts has been associated with segmental instability. Given this association, decompression versus decompression with fusion is a frequently debated topic. Multiple grading scales have been devised to identify patients at high risk for development of cyst recurrence; however, there exists no external evaluation of these scales.

METHODS

A retrospective review of 54 patients undergoing initial treatment for lumbar synovial cysts at a single institution over the past 12 years was conducted. Surgical treatment consisted of decompression with cystectomy without fusion. Patients were assessed and classified according to the NeuroSpine Surgery Research Group (NSURG) and Rosenstock Classification systems. Five neurosurgeons reviewed the preoperative magnetic resonance images, and results were classified. Interrater reliability was assessed using both Gwet's AC1 coefficient and Krippendorff's alpha. A 1-way analysis of variance was used to evaluate predictive ability of both classification systems.

RESULTS

In total, of the 54 patients who underwent decompression, 7 had cyst recurrence. Overall cyst recurrence was most common in NSURG grade 2 cysts (3/12, 25%) followed by grade 1 cysts (4/27, 14.8%). Of the NSURG grade 3 and 4 patients, none had cyst recurrence. In the Rosenstock grades the most common recurrence was in grade 3 cysts (1/4, 25%) followed by grade 1 cysts (5/26, 19.2%). Interrater reliability demonstrated good reproducibility on Gwet's AC1 and Krippendorff's alpha on both grading scales. Neither score was predictive of cyst recurrence (P > 0.05).

CONCLUSIONS

The Rosenstock and NeuroSpine scores demonstrate good overall interrater reliability but are inconsistent in their ability to predict recurrence of lumbar facet cysts.

Clinical outcomes in revision lumbar spine fusions: an observational cohort study

OBJECTIVE

The authors compared primary lumbar spine fusions with revision fusions by using patient Oswestry Disability Index (ODI) scores to evaluate the impact of the North American Spine Society (NASS) evidence-based medicine (EBM) lumbar fusion indications on patient-reported outcome measures of revision surgeries.

METHODS

This study was a retrospective analysis of a prospective observational cohort of patients who underwent elective lumbar fusion between January 2018 and December 2019 at a single quaternary spine surgery service and had a minimum of 6 months of follow-up. A prospective quality improvement database was constructed that included the data from all elective lumbar spine surgeries, which were categorized prospectively as primary or revision surgeries and EBM-concordant or EBM-discordant revision surgeries based on the NASS coverage EBM policy. In total, 309 patients who met the inclusion criteria were included in the study. The ODIs of all groups (primary, revision, revision EBM concordant, and revision EBM discordant) were statistically compared. Differences in frequencies between cohorts were evaluated using chi-square and Fisher's exact tests. The unpaired 2-tailed Student t-test and the Mann-Whitney U-test for nonparametric data were used to compare continuous variables. Logistic regression was performed to determine the associations between independent variables (surgery status and NASS criteria indications) and functional outcomes.

RESULTS

Primary lumbar fusions were significantly associated with improved functional outcomes compared with revisions, as evidenced by ODI scores (OR 1.85, 95% CI 1.16-2.95 to achieve a minimal clinically important difference, p = 0.01). The percentage of patients whose functional status had declined at the 6-month postoperative evaluation was significantly higher in patients who had undergone a revision surgery than in those who underwent a primary surgery (23% vs 12.3%, respectively). An increase in ODI score, indicating worse clinical outcome after surgery, was greater in patients who underwent revision procedures (OR 2.14, 95% CI 1.17-3.91, p = 0.0014). Patients who underwent EBM-concordant revision surgery had significantly improved mean ODI scores compared with those who underwent EBM-discordant revision surgery (7.02 ± 5.57 vs -4.6 ± 6.54, p < 0.01).

CONCLUSIONS

The results of this prospective quality improvement program investigation illustrate that outcomes of primary lumbar fusions were superior to outcomes of revisions. However, revision procedures that met EBM guidelines were associated with greater improvements in ODI scores, which indicates that the use of defined EBM guideline criteria for reoperation can improve clinical outcomes of revision lumbar fusions.

Preoperative Cyst Formation as a Predictive Feature of Spontaneous Regression of Retro-Odontoid Pseudotumor After Posterior Fusion

OBJECTIVE

Although the spontaneous regression of pseudotumors after posterior fusion has been reported, the predictive factors remain unclear. We examined the radiological features that predict for the regression of retro-odontoid pseudotumors after posterior fusion, with a specific focus on cyst formation.

METHODS

We included 28 patients with a diagnosis of retro-odontoid pseudotumor using preoperative magnetic resonance imaging. The radiographic parameters and pseudotumor thickness were measured pre- and postoperatively. The regression rate for each pseudotumor was calculated. The presence of a cyst around the retro-odontoid pseudotumor was investigated. If present, the cyst thickness was measured. To elucidate the predictors for the postoperative regression of pseudotumors, the patients were divided into 2 cohorts: the regression group with a regression rate >40% and the no-regression group with a regression rate of <40%. Multivariate logistic regression analysis, including the demographic data and preoperative radiographic parameters as independent variables, was performed.

RESULTS

The mean pseudotumor size had decreased significantly from 8.8 ± 3.6 mm preoperatively to 5.3 ± 2.0 mm postoperatively (P < 0.0001). The mean regression rate was 35.9% during a magnetic resonance imaging follow-up period of 8.6 months (range, 6-12 months). Cystic lesions were noted in 10 patients (35.7%) preoperatively. The mean cyst size was 4.7 ± 1.9 mm. All cysts were located dorsal to the pseudotumors and were involved at the maximum spinal compression levels. Nevertheless, all the cysts had disappeared postoperatively. Multivariate logistic regression analysis revealed that the pseudotumor regression group had had a significantly greater proportion of cysts (57.1% vs. 14.3%; odds ratio, 11.7; P = 0.013).

CONCLUSIONS

The presence of cystic lesions protruding from retro-odontoid pseudotumors might serve as a predictive factor for the spontaneous regression of pseudotumors after posterior fusion.

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.

Complete Resolution of a Large Hemorrhagic Lumbar Synovial Cyst Following Spinal Fusion Alone

The authors reported complete regression of a large hemorrhagic lumbar synovial cyst following posterior spinal fusion without direct cystic resection. A 64-year-old woman suffered from sudden onset of the left buttock pain radiating to the left leg after waking up in the morning following the previous history of a minor accident 2 months ago. Magnetic resonance imaging (MRI) of the lumbosacral spine showed a large extradural round mass originating from the left facet joint at the level of L3–L4. The mass was hyperintense on T1-weighted images and hypointense on T2-weighted images, probably compatible with hemorrhagic joint-related cyst. Surgical treatment was chosen for her because of persistent left radicular pain with no responding to medications. The patient underwent decompressive laminectomy, subtotal facetectomy, instrumented fusion, and only tissue biopsy due to severe adherence of the mass and dura. Histopathological examination was consistent with a hemorrhagic synovial cyst. The radicular pain completely disappeared after the surgery. Follow-up MRI of the lumbosacral spine obtained 6 months after the surgery demonstrated complete resolution of the hemorrhagic cyst. Complete resolution of hemorrhagic synovial cyst seems to correlate with subtotal facetectomy, probably resulting in leakage of cyst content and subsequent resorption of the cyst wall. In addition, hematoma within the synovial cyst may resolve spontaneously over time.

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.

Management of Postoperative Facet Cysts: A Report of 3 Cases

CASE

The exact underlying etiology behind synovial facet cysts remains unclear, and optimal surgical management continues to be a challenge. The authors present a series of 3 patients who underwent primary lumbar decompression and developed postoperative facet cysts within 6 months of index surgery requiring operative intervention. No patients had radiographic evidence of instability. Average follow-up after revision surgery was 14 months.

CONCLUSION

We report on the 3 cases with the phenomenon of postoperative facet cysts and present a complication that falls within the spectrum of lumbar decompression surgery with several successful treatment options.

Rapid Neurologic Deterioration due to an Enlarging Thoracic Spine Synovial Cyst: A Case Report

CASE

We present the case of a 69-year-old man arriving to our clinic after a previous outside hospital recommendation of L1-S1 fusion due to degenerative scoliosis. A thoracic spine synovial cyst was identified through magnetic resonance imaging. The patient had rapid progression of his neurologic deficit due to cyst enlargement. We elected to perform cyst decompression and instrumented fusion of the involved thoracic segment. The patient rapidly regained full neurologic function. After the one-year follow-up, he remained asymptomatic with no progression of thoracolumbar degeneration.

CONCLUSIONS

Thoracic spine synovial facet cysts are uncommonly encountered. Decompression alone or decompression and fusion are both viable treatment options depending on the surgeon's assessment of spine stability after decompression. This diagnosis should be considered in patients presenting with unilateral lower extremity upper motor neuron findings.

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 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.

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.

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.

Surgical Treatment of Spinal Synovial Cysts in Elderly Patients: Symptoms, Treatment Course, and Outcome in Patients >75 Years of Age

BACKGROUND

With the aging of our society comes a rising number of elderly patients with progressive degeneration of the spine associated with synovial cysts. Surgical treatment may be particularly challenging in elderly patients because of comorbidities.

METHODS

Patients treated in our department between 1999 and 2014 for spinal synovial cysts were screened. The 28 patients ≥75 years old were classified as elderly and were compared with 96 patients 50-74 years old. No patient underwent fusion as part of cyst resection.

RESULTS

Despite a significantly higher frequency of muscle reflex changes in elderly patients at presentation, symptoms, cyst levels, rate of complications, and surgical method were not different between groups. Cyst adherence to the dura and subtotal resection were observed significantly more often in the elderly group (18% vs. 3%; P < 0.05). Outcome according to the Oswestry Disability Index was classified as no disability or minimal disability in 85% of the elderly group and in 82% of the control group. Recurrent cyst and delayed fusion rates were lower in the elderly group (4% and 4%) compared with the control group (7% and 8%).

CONCLUSIONS

The clinical course of elderly patients with surgical treatment of spinal synovial cysts did not differ compared with younger patients. Good or excellent results could be achieved and persisted for a long time in most cases. Fusion should be performed only in cases of severe instability. Nonaggressive cyst removal in cases of dural attachment enables low cerebrospinal fluid fistula rates without increasing cyst recurrence rates.

Percutaneous Translaminar Facet Cyst Rupture and Epidural Access-Description of a Novel Technique

Synovial cysts of the lumbar zygapophysial joints can be treated by percutaneous injection of corticosteroids, with distension and rupture of the cyst. Some cysts can be difficult to access, particularly when they lie deep in relation to the lamina. This technical report describes a fluoroscopy-guided technique for accessing sublaminar pathology. Crucial to the safety of the technique is visualization of the ventral margin of the lamina using a contralateral oblique view, and controlling and limiting the insertion of the needle such that only its tip passes the lamina.

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.

Synovial cysts of the spine: long-term follow-up after surgical treatment of 141 cases in a single-center series and comprehensive literature review of 2900 degenerative spinal cysts

OBJECTIVE Synovial cysts of the spine are rare lesions, predominantly arising in the lumbar region. Despite their generally benign behavior, they can cause severe symptoms due to compression of neural structures in the spinal canal. Treatment strategies are still a matter of discussion. The authors performed a single-center survey and literature search focusing on long-term results after minimally invasive surgery. METHODS A total of 141 consecutive patients treated for synovial cysts of the lumbar spine between 1997 and 2014 in the authors' department were analyzed. Medical reports with regard to signs and symptoms, operative findings, complications, and short-term outcome were reviewed. Assessment of long-term outcome was performed with a standardized telephone questionnaire based on the Oswestry Disability Index (ODI). Furthermore, patients were questioned about persisting pain, symptoms, and further operative procedures, if any. Subjective satisfaction was classified as excellent, good, fair, or poor based on the Macnab classification. RESULTS The approach most often used for synovial cyst treatment was partial hemilaminectomy in 70%; hemilaminectomy was necessary in 27%. At short-term follow-up, the presence of severe and moderate leg pain had decreased from 93% to 5%. The presence of low-back pain decreased from 90% to 5%. Rates of motor and sensory deficits were reduced from 40% to 14% and from 45% to 6%, respectively. The follow-up rate was 58%, and the mean follow-up period was 9.3 years. Both leg pain and low-back pain were still absent in 78%. Outcome based on the Macnab classification was excellent in 80%, good in 14%, fair in 1%, and poor in 5%. According to the ODI, 78% of patients had no or only minimal disability, 16% had moderate disability, and 6% had severe disability at the time of follow-up. In this cohort, 7% needed surgery due to cyst recurrence, and 9% required a delayed stabilization procedure after the initial operation. CONCLUSIONS Surgical treatment with resection of the cyst provides favorable results in outcome. Excellent or good outcome persisting for a long-term follow-up period can be achieved in the vast majority of cases. Complication rates are low despite an increased risk of dural injury. With facet-sparing techniques, the stability of the segment can be preserved, and resection of spinal synovial cysts does not necessarily require segmental fusion.

Thoracic juxtafacet cyst (JFC): a cause of spinal myelopathy

Spinal cord compression due to synovial facet cyst in thoracolumbar spine is rare. Several etiologies of juxtafacet cysts (JFCs) in this location have been discussed, particularly overload of the arthritic facet joints. Due to the narrow caliber of the thoracic spine, JFC in this location can present with radicular pain or progressive myelopathy. We report an interesting case of a 67 year-old woman who presented with the signs and symptoms of thoracic myelopathy. A left-sided T11/12 JFC was identified on MRI and CT scans correlating with her myelopathy. She experienced a substantial improvement in her myelopathic symptoms after surgical excision of the JFC. The presentation, etiology, and therapeutic aspects of JFC are discussed in detail.

Long-term outcomes of percutaneous lumbar facet synovial cyst rupture

OBJECTIVE

To evaluate the therapeutic value, safety, and long-term clinical outcomes of percutaneous lumbar facet synovial cyst (LFSC) rupture.

MATERIALS AND METHODS

Our study was institutional review board (IRB)-approved and Health Insurance Portability and Accountability Act (HIPAA)-compliant. The study group comprised 71 patients (44 women, mean age: 65 ± 17 years) who underwent CT- or fluoroscopy-guided percutaneous LFSC rupture. The technical success of LFSC rupture, the long-term clinical outcome, including repeat procedures or surgery, and imaging findings on MRI and CT were recorded.

RESULTS

Seventy-nine LFSC ruptures were performed in 71 patients. CT guidance was used in 57 cases and fluoroscopy guidance in 22 cases. LFSC rupture was technically successful in 58 out of 79 cases (73 %). Mean injection volume for cyst rupture was 3.6 ± 2.2 mL and a combination of steroid and anesthetic was injected in all cases. Over a mean follow-up time of 44 months, 12 % of patients underwent repeat cyst rupture, and 46 % eventually underwent surgery, whereas the majority of patients (55 %) experienced symptomatic relief and did not undergo surgery. There was no significant association between a successful outcome and age, sex, level, or size of LFSC (p > 0.1). LFSCs with T2 hypointensity were more likely to require surgery (p = 0.02). There was one complication, a bacterial skin infection that completely resolved following antibiotic therapy.

CONCLUSION

Percutaneous LFSC rupture is an effective and safe nonsurgical treatment option for LFSC. More than half of treated patients were able to avoid subsequent surgery. Therefore, percutaneous LFSC rupture should be considered before surgical intervention.

Evaluation and Treatment of Lumbar Facet Cysts

Lumbar facet cysts are a rare but increasingly common cause of symptomatic nerve root compression and can lead to radiculopathy, neurogenic claudication, and cauda equina syndrome. The cysts arise from the zygapophyseal joints of the lumbar spine and commonly demonstrate synovial herniation with mucinous degeneration of the facet joint capsule. Lumbar facet cysts are most common at the L4-L5 level and often are associated with spondylosis and degenerative spondylolisthesis. Advanced imaging studies have increased diagnosis of the cysts; however, optimal treatment of the cysts remains controversial. First-line treatment is nonsurgical management consisting of oral NSAIDs, physical therapy, bracing, epidural steroid injections, and/or cyst aspiration. Given the high rate of recurrence and the relatively low satisfaction with nonsurgical management, surgical options, including hemilaminectomy or laminotomy to excise the cyst and decompress the neural elements, are typically performed. Recent studies suggest that segmental fusion of the involved levels may decrease the risks of cyst recurrence and radiculopathy.

Spontaneous resolution of symptomatic lumbar synovial cyst

Lumbar synovial cyst arises from the facet joint and can lead to back pain, radiculopathy, neurogenic claudication or even cauda equina syndrome. Although most surgeons would consider surgery to be the treatment of choice, the natural history of the disease process remains unknown and uncertainty still exists regarding optimal management of this controversial entity. We illustrate a case of large L5/S1 synovial cyst for which surgery was initially planned. However, it resolved spontaneously without any treatment. We also provide a brief literature review regarding conservative, surgical and minimally invasive management of symptomatic lumbar synovial cyst with special reference to patient outcome.