Preoperative Spondylolisthesis Research Articles

Could indirect decompression occur for cord compression by the ligamentum flavum with anterior cervical discectomy and fusion?

Cord compression by the ligamentum flavum (CCLF) has been reported to adversely affect the clinical outcomes of anterior cervical discectomy and fusion (ACDF). While indirect decompression does occur for foraminal stenosis with ACDF, whether ACDF could improve CCLF with the distraction of disc space remains unclear. This study aimed to identify 1) whether indirect decompression occurs for CCLF with ACDF, and 2) risk factors that hinder the improvement of CCLF. This retrospective cohort study included 119 patients who underwent ACDF for the treatment of cervical myelopathy and CCLF was detected on preoperative MRI. Patients who demonstrated improvement in CCLF grade after ACDF were included in the improved group, while those who did not show improvement were classified as the unimproved group. Patient characteristics, cervical sagittal parameters, neck and arm pain visual analog scale score, and Japanese Orthopaedic Association (JOA) score were assessed. A comparison between the improved and unimproved groups was performed. Regression analyses were performed to identify factors associated with CCLF grade improvement. Overall, 58.0% (69/119) of patients showed improvement in CCLF grade after ACDF. CCLF grade did not improve in the remaining 42.0% (50/119) of patients, and 3.4% (4/119) of patients experienced aggravation of CCLF after ACDF. Preoperative spondylolisthesis (OR 0.252, 95% CI 0.090-0.711; p = 0.009) and greater segmental lordosis 3 months postoperatively (OR 0.835, 95% CI 0.731-0.953; p = 0.008) were the factors that hindered the improvement of CCLF after ACDF. Furthermore, patients with higher pre- or postoperative CCLF grades showed significantly less improvement in JOA score 2 years postoperatively. Indirect decompression for CCLF with ACDF is not reliable because 42.0% of patients did not demonstrate improvement in CCLF grade after the operation. Preoperative spondylolisthesis and postoperative increased segmental lordosis were risk factors for failure of CCLF improvement. Both pre- and postoperative higher CCLF grades were associated with poor neurological recovery 2 years postoperatively.

Functional & Clinical Outcomes of Posterior Decompression & Transforaminal Lumbar Interbody Fusion (TLIF) Using Cage and Bone Graft Combined with Stabilization in Lumbar Spondylolisthesis

Introduction: Posterior decompression and transforaminal lumbar interbody fusion (TLIF) using cage and bone graft is a surgical technique for treating lumbar spondylolisthesis. This procedure aims to relieve spinal pressure and stabilize the affected vertebral segments. Aim of the study: The aim of this study was to assess the clinical and functional outcomes of posterior decompression & transforaminal lumbar interbody fusion (TLIF) using cage and bone graft combined with stabilization in lumbar spondylolisthesis. Methods: This prospective observational study was carried out at NITOR, Dhaka, Bangladesh, during the period from January 2020 to December 2021. Total 15 patients with degenerative lumbar spondylolisthesis were included in this study. Result: The study assessed 15 patients undergoing surgery for spondylolisthesis, primarily aged 40-49, with a mean age of 46.4 years. Gender distribution was 40% male, 60% female. Pre-operative spondylolisthesis was mostly at L4/L5 (60%) and L5/S1 (40%). Post-op data showed significant reductions in slip angle and VAS scores for back and leg pain (all P<0.05). Foraminal and disc space height increased. Fusion rate was 86.66% per Hackenberg criteria. Motor deficit improved from 33.3% to 6.7% post-op. According to Macnab criteria, 73% had excellent functional outcomes and 26.66% experienced minor complications; no major complications were recorded. Conclusion: As observed from the result of this study, degenerative lumber spondylolisthesis can be treated with posterior decompression and transforaminal lumbar interbody fusion by using cage and bone graft with spinal stabilization. This method enhances neurological recovery, reduces pain and makes the patients able to return to work comfortably.

Reduction of spondylolisthesis and restoration of lumbar lordosis after anterior lumbar interbody fusion (ALIF)

BackgroundAnterior lumbar interbody fusion (ALIF) is a well-established surgical treatment option for various diseases of the lumbar spine, including spondylolisthesis. This study aimed to evaluate the postoperative correction of spondylolisthesis and restoration of lumbar and segmental lordosis after ALIF.MethodsPatients with spondylolisthesis who underwent ALIF between 2013 and 2019 were retrospectively assessed. We assessed the following parameters pre-and postoperatively (6-months follow-up): Visual Analogue Scale (VAS) for pain, Oswestry Disability Index (ODI), lumbar lordosis (LL), segmental lordosis (SL), L4/S1 lordosis, and degree of spondylolisthesis.Results96 patients were included. In 84 cases (87.50%), additional dorsal instrumentation was performed. The most frequent diagnosis was isthmic spondylolisthesis (73.96%). VAS was reduced postoperatively, from 70 to 40, as was ODI (50% to 32%). LL increased from 59.15° to 64.45°, as did SL (18.95° to 28.55°) and L4/S1 lordosis (37.90° to 44.00°). Preoperative spondylolisthesis was 8.90 mm and was reduced to 6.05 mm postoperatively. Relative spondylolisthesis was 21.63% preoperatively and 13.71% postoperatively. All clinical and radiological improvements were significant (all p < 0.001). No significant difference considering the lordosis values nor spondylolisthesis was found between patients who underwent ALIF surgery without dorsal instrumentation and patients who received additional dorsal instrumentation. Venous laceration was the most frequent complication (10.42%).ConclusionsWith ALIF, good clinical results and safe and effective reduction of spondylolisthesis and restoration of lordosis can be achieved. Additional dorsal instrumentation does not significantly affect postoperative lordosis or spondylolisthesis. Individual vascular anatomy must be reviewed preoperatively before considering ALIF.

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

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. 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. 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. 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.

Factors associated with an increased risk of developing postoperative symptomatic lumbar spondylolisthesis after decompression surgery: an explorative two-centre international cohort study

PurposeSymptomatic lumbar spinal stenosis can be treated with decompression surgery. A recent review reported that, after decompression surgery, 1.6–32.0% of patients develop postoperative symptomatic spondylolisthesis and may therefore be indicated for lumbar fusion surgery. The latter can be more challenging due to the altered anatomy and scar tissue. It remains unclear why some patients get recurrent neurological complaints due to postoperative symptomatic spondylolisthesis, though some associations have been suggested. This study explores the association between key demographic, biological and radiological factors and postoperative symptomatic spondylolisthesis after lumbar decompression.MethodsThis retrospective cohort study included patients who had undergone lumbar spinal decompression surgery between January 2014 and December 2016 at one of two Spine Centres in the Netherlands or Switzerland and had a follow-up of two years. Patient characteristics, details of the surgical procedure and recurrent neurological complaints were retrieved from patient files. Preoperative MRI scans and conventional radiograms (CRs) of the lumbar spine were evaluated for multiple morphological characteristics. Postoperative spondylolisthesis was evaluated on postoperative MRI scans. For variables assessed on a whole patient basis, patients with and without postoperative symptomatic spondylolisthesis were compared. For variables assessed on the basis of the operated segment(s), surgical levels that did or did not develop postoperative spondylolisthesis were compared. Univariable and multivariable logistic regression analyses were used to identify associations with postoperative symptomatic spondylolisthesis.ResultsSeven hundred and sixteen patients with 1094 surgical levels were included in the analyses. (In total, 300 patients had undergone multilevel surgery.) ICCs for intraobserver and interobserver reliability of CR and MRI variables ranged between 0.81 and 0.99 and 0.67 and 0.97, respectively. In total, 66 of 716 included patients suffered from postoperative symptomatic spondylolisthesis (9.2%). Multivariable regression analyses of patient-basis variables showed that being female [odds ratio (OR) 1.2, 95%CI 1.07–3.09] was associated with postoperative symptomatic spondylolisthesis. Higher BMI (OR 0.93, 95%CI 0.88–0.99) was associated with a lower probability of having postoperative symptomatic spondylolisthesis.Multivariable regression analyses of surgical level-basis variables showed that levels with preoperative spondylolisthesis (OR 17.30, 95%CI 10.27–29.07) and the level of surgery, most importantly level L4L5 compared with levels L1L3 (OR 2.80, 95%CI 0.78–10.08), were associated with postoperative symptomatic spondylolisthesis; greater facet joint angles (i.e. less sagittal-oriented facets) were associated with a lower probability of postoperative symptomatic spondylolisthesis (OR 0.97, 95%CI 0.95–0.99).ConclusionBeing female was associated with a higher probability of having postoperative symptomatic spondylolisthesis, while having a higher BMI was associated with a lower probability. When looking at factors related to postoperative symptomatic spondylolisthesis at the surgical level, preoperative spondylolisthesis, more sagittal orientated facet angles and surgical level (most significantly level L4L5 compared to levels L1L3) showed significant associations. These associations could be used as a basis for devising patient selection criteria, stratifying patients or performing subgroup analyses in future studies regarding decompression surgery with or without fusion.

Revision surgery following minimally invasive decompression for lumbar spinal stenosis with and without stable degenerative spondylolisthesis: a 5- to 15-year reoperation survival analysis.

Minimally invasive decompression (MID) is an effective procedure for lumbar spinal stenosis (LSS). Long-term follow-up data on reoperation rates are lacking. The objective of this retrospective cohort study was to evaluate reoperation rates in patients with LSS who underwent MID, stratified for degenerative lumbar spondylolisthesis (DLS), with a follow-up between 5 and 15 years. All consecutive patients with LSS who underwent MID between 2002 and 2011 were included. All patients had neurogenic claudication from central and/or lateral recess stenosis, without or with up to 25% of slippage (grade I spondylolisthesis), and no obvious dynamic instability on imaging (increase in spondylolisthesis by ≥ 5 mm demonstrated on supine-to-standing or flexion-extension imaging). Reoperation rates defined as any operation on the same or adjacent level were assessed. Revision decompression alone was considered if the aforementioned clinical and radiographic criteria were met; otherwise, patients underwent a minimally invasive posterior fusion. A total of 246 patients (mean age 66 years) were included. Preoperative spondylolisthesis was present in 56.9%. The mean follow-up period was 8.2 years (range 5.0-14.9 years). The reoperation rates in patients with and without spondylolisthesis were 15.7% and 15.1%, respectively; fusion was required in 7.1% and 7.5%, with no significant difference (redecompression only, p = 0.954; fusion, p = 0.546). For decompression only, the mean times to reoperation were 3.9 years (95% CI 1.8-6.0 years) for patients with DLS and 2.8 years (95% CI 1.3-4.2 years) for patients without DLS; for fusion, the mean times to reoperation were 3.1 years (95% CI 1.0-5.3 years) and 3.1 years (95% CI 1.1-5.1 years), respectively. In highly selected patients with stable DLS and leg-dominant pain from central or lateral recess stenosis, the long-term reoperation rate is similar between DLS and non-DLS patients undergoing MIS decompression.

Cross-sectional area of the longus colli and cervical degenerative spondylolisthesis: A retrospective review evaluating this anatomic consideration.

Limited literature is available to define the impact of the longus colli muscle, a deep flexor of the spine, on cervical spine stability despite its close proximity to the vertebrae. The purpose of this study was to determine if longus colli cross-sectional area (CSA) is associated with the severity preoperative cervical degenerative spondylolisthesis. Patients undergoing elective anterior cervical discectomy and fusion (ACDF) for cervical spondylolisthesis between 2010-2021 were retrospectively identified. Longus colli cross-sectional areas (CSA) were measured from preoperative MRI images at the C5 level. Preoperative spondylolisthesis measurements were recorded with cervical radiographs. Patients were grouped by quartiles respectively according to longus colli CSAs. Statistical tests compared patient demographics, surgical characteristics, and surgical outcomes between groups. Multiple linear regression analysis was utilized to assess if longus colli CSA predicted cervical spondylolisthesis. A total of 157 patients met inclusion criteria. Group 1 (first quartile) was the oldest (60.4 ± 12.0 years, P = 0.024) and was predominantly female (59.0%, P = 0.001). Group 1 also had the highest maximum spondylolisthesis (0.19 mm, P = 0.031) and highest proportion of grade 2 spondylolisthesis (23.1%, P = 0.003). On regression analysis, lowest quartile of longus colli CSA was an independent predictor of larger measured maximum spondylolisthesis (β: 0.04, P = 0.012). Smaller longus colli CSA is independently associated with a higher grade and degree of preoperative cervical spondylolisthesis, but this finding does not result in adverse postsurgical outcomes.

Predictors of indirect neural decompression in minimally invasive transpsoas lateral lumbar interbody fusion.

An advantage of lateral lumbar interbody fusion (LLIF) surgery is the indirect decompression of the neural elements that occurs because of the resulting disc height restoration, spinal realignment, and ligamentotaxis. The degree to which indirect decompression occurs varies; no method exists for effectively predicting which patients will respond. In this study, the authors identify preoperative predictive factors of indirect decompression of the central canal. The authors performed a retrospective evaluation of prospectively collected consecutive patients at a single institution who were treated with LLIF without direct decompression. Preoperative and postoperative MRI was used to grade central canal stenosis, and 3D volumetric reconstructions were used to measure changes in the central canal area (CCA). Multivariate regression was used to identify predictive variables correlated with radiographic increases in the CCA and clinically successful improvement in visual analog scale (VAS) leg pain scores. One hundred seven levels were treated in 73 patients (mean age 68 years). The CCA increased 54% from a mean of 0.96 cm2 to a mean of 1.49 cm2 (p < 0.001). Increases in anterior disc height (74%), posterior disc height (81%), right (25%) and left (22%) foraminal heights, and right (12%) and left (15%) foraminal widths, and reduction of spondylolisthesis (67%) (all p < 0.001) were noted. Multivariate evaluation of predictive variables identified that preoperative spondylolisthesis (p < 0.001), reduced posterior disc height (p = 0.004), and lower body mass index (p = 0.042) were independently associated with radiographic increase in the CCA. Thirty-two patients were treated at a single level and had moderate or severe central stenosis preoperatively. Significant improvements in Oswestry Disability Index and VAS back and leg pain scores were seen in these patients (all p < 0.05). Twenty-five (78%) patients achieved the minimum clinically important difference in VAS leg pain scores, with only 2 (6%) patients requiring direct decompression postoperatively due to persistent symptoms and stenosis. Only increased anterior disc height was predictive of clinical failure to achieve the minimum clinically important difference. LLIF successfully achieves indirect decompression of the CCA, even in patients with substantial central stenosis. Low body mass index, preoperative spondylolisthesis, and disc height collapse appear to be most predictive of successful indirect decompression. Patients with preserved disc height but severe preoperative stenosis are at higher risk of failure to improve clinically.

Long-Term Outcomes Following Lumbar Microendoscopic Decompression for Lumbar Spinal Stenosis with and without Degenerative Spondylolisthesis: Minimum 10-Year Follow-Up

To determine whether preoperative presence of degenerative lumbar spondylolisthesis (DS) worsens the minimum 10-year outcome of patients undergoing microendoscopic decompression (MED) for lumbar spinal stenosis (SS). Eighty patients undergoing MED were classified into 2 groups: DS group (34 SS with DS patients) and SS group (46 SS without DS patients). The degrees of improvement (DOIs) by the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) and intensities of improvement (IOIs) by Visual Analog Scale (VAS) at 120-159 (mean, 138.4) months after MED of the DS and SS groups were statistically compared. Patients with DS were classified into 2 groups based on the effectiveness by VAS or JOABPEQ: effective group (E group: IOI or DOI ≥20) and ineffective group (I group). All preoperative radiologic measurements were statistically compared between the E and I groups. Significant decreases in low back pain, leg pain, and numbness, as measured by VAS, were noted at follow-up in the DS and SS groups. The effectiveness rates of pain-related disorders, lumbar spine dysfunction, and gait disturbance by JOABPEQ were almost equally high in the DS and SS groups. Statistical comparisons of the DOIs in all 5 functional scores and IOIs in low back pain, leg pain, and numbness showed no significant differences between the DS and SS groups. No significant differences were confirmed between the E and I groups concerning preoperative spondylolisthesis and instability. Our study indicated that preoperative DS did not worsen the outcome of patients with SS undergoing MED.

Are degenerative spondylolisthesis and further slippage postoperatively really issues in spinal stenosis surgery?

Background and aims Opinions diverge concerning the prognostic importance of preoperative degenerative spondylolisthesis in patients with lumbar spinal stenosis, as well as the significance of further slippage post-operatively following decompression alone. However, a slip is only one among several factors related to the topic, e.g. duration and intensity of back and leg pain, pre-operative walking ability, number of levels operated and not least the experience of the surgeon. Our aim was to take all of the above-mentioned factors into consideration when analysing the patients' clinical outcome, reported as Change in back pain, Change in leg pain, Overall satisfaction and Change in walking ability, with special emphasis on the possible importance of pre- and/or post-operative degenerative spondylolisthesis. Methods We studied 200 consecutive patients, mean follow-up time 81 months (range 62-108). Before treatment and on the follow-up occasion all patients answered the SF-36 questionnaire and assessed their back and leg pain on a visual analogue scale (VAS). At follow-up the patients were asked about possible changes in back and leg pain (completely free, much better, somewhat better, unchanged, somewhat worse, much worse) and whether they were; satisfied with the outcome, in doubt or not satisfied. Before treatment and at follow-up the presence or not of degenerative spondylolisthesis was determined in the lateral view on a plain X-ray or MRI. By use of a microsurgical technique decompression was achieved in all patients by bilateral laminotomy not sparing the midline ligaments, irrespective of a degenerative spondylolisthesis or not. Eight surgeons with different surgical experience performed the operations. Four separate multivariate analyses were conducted, one for each clinical outcome. The Lasso method was used for variable selection and multiple imputation was applied to handle missing values. Results At follow-up 78.5% of the patients were completely satisfied with the outcome. Minimal clinical important difference (MCID) was achieved for 69% of the patients. Before surgery 28 patients were able to walk more than 1 km compared to 111 at follow-up. The reoperation rate at 6.8 years was 12% further decompressions and 2.5% fusions at the index level. Post-operative slippage was equally common in patients with and without a preoperative slip (around 30%). There were no notable differences in outcome in patients with and without a preoperative slip and no effect of further slippage at the index or another level post-operatively. Nor could the statistical analysis show any of the other covariates (age, gender, duration and intensity of back and leg pain, pre-operative walking ability or number of levels operated) to be of statistically significant importance for predicting the outcome. In the univariate statistical analysis differences were found between the patients of individual surgeons regarding satisfaction, pain improvement, and reoperation rates in favour of surgical experience, which were, however, not statistically significant in the multivariate analysis. Conclusions None of the covariates, including pre-operative spondylolisthesis and further slippage post-operatively, were statistically significant for predicting the clinical outcome. Implication Our results provide no evidence for adding fusion to the decompression.

Endoscopic posterior decompression under local anesthesia for degenerative lumbar spinal stenosis.

OBJECTIVEVarious minimally invasive techniques have been described for the decompression of lumbar spinal stenosis (LSS). However, few reports have described the results of endoscopic posterior decompression (EPD) with laminectomy performed under local anesthesia. This study aimed to evaluate the clinical and radiological outcomes of EPD performed under local anesthesia in patients with LSS and to compare the procedural outcomes in patients with and without preoperative spondylolisthesis.METHODSFifty patients (28 female and 22 male) who underwent EPD under local anesthesia were included in this study. Patients were assessed before surgery and were followed up with regular outpatient visits (at 1, 3, 6, 12, and 24 months postoperatively). Clinical outcomes were evaluated using the visual analog scale (VAS), Oswestry Disability Index (ODI), and the 36-Item Short Form Survey (SF-36) outcome questionnaire. Radiological outcomes were assessed by measuring lumbar lordosis, disc-wedging angle, percentage of vertebral slippage, and disc height index on plain standing radiographs.RESULTSThe VAS, ODI, and SF-36 scores were significantly improved at 1 month after surgery compared to the baseline mean values, and the improved scores were maintained over the 2-year follow-up period. Radiological progression was found in 2 patients during the follow-up period. Patients with and without preoperative spondylolisthesis had no significant differences in their clinical and radiological outcomes.CONCLUSIONSEPD performed under local anesthesia is effective for LSS treatment. Similar favorable outcomes can be obtained in patients with and without preoperative spondylolisthesis using this approach.

Feasibility of Full Percutaneous Segmental Stabilization of the Lumbar Spine With a Combination of an Expandable Interbody Cage and an Interspinous Spacer: Preliminary Results.

We evaluated the feasibility of a full percutaneous approach with an expandable interbody cage and an interspinous spacer for a segmental stabilization of the anterior and posterior columns of the lumbar spine, respectively, with local anesthesia. Patients were prospectively included between 2012 and 2018 in this single-center, feasibility case series. An expandable interbody cage was inserted with endoscopy-based, facet-sparing percutaneous transforaminal lumbar interbody fusion (pTLIF). An interspinous spacer was percutaneously placed through the same skin incision. Pre- and postoperative Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) outcomes at 1, 3, 6, 12, and 24 months were obtained and evaluated with the Student t test. Postoperative outcome was classified according to modified Macnab criteria. A total of 16 patients were included, presenting mean preoperative scores for VAS back of 6.9 ± 2.5, VAS leg 7.9 ± 1.2, and ODI 30.1 ± 4.5. Postoperative mean scores for VAS back of 1.9 ± 2.1, VAS leg 2.1 ± 3.4, and ODI 14.8 ± 13.0 significantly (P < .001) decreased with a mean follow-up of 18.1 ± 16.6 months (range 1-65.2). Postoperative outcome was excellent and good for 13 (81%) cases, fair for 2 (13%), and poor for 1 (6%) case with a preoperative spondylolisthesis, which required revision surgery due to persisting instability. Postoperative complications included 3 cases with transitory, ipsilateral dysesthesia and 2 cases with radiologic cage subsidence but no clinical symptoms. Median postoperative time until hospital discharge was 16 hours. Our preliminary results for this full percutaneous technique show a similar outcome compared to conventional surgery with a fast patient recovery and early postoperative hospital discharge, opening the way to instrumented, outpatient surgery.

Synovial Cyst as a Marker for Lumbar Instability: A Systematic Review and Meta-Analysis

The pathogenesis of synovial cysts is largely unknown; however, they have been increasingly thought of as markers of spinal facet instability and typically associated with degenerative spondylosis. We specifically investigated the incidence of concomitant synovial cysts with underlying degenerative spondylolisthesis. A literature search was performed using 4 online databases to assess the association between lumbar synovial cysts and degenerative spinal pathological features. Meta-analyses were performed on the prevalence rates of coexisting degenerative spinal pathological entities and treatment modalities. A random effects model was used to calculate the mean and 95% confidence intervals. A total of 17 studies encompassing 824 cases met the inclusion criteria. The pooled prevalence rates of concurrent spondylolisthesis, facet arthropathy, and degenerative disc disease at the same level of the synovial cysts were 42.5% (range, 39.0%-46.1%), 89.3% (range, 79.0%-94.8%), and 48.8% (range, 43.8%-53.9%), respectively. Among these, patients with coexisting spondylolisthesis were more likely to undergo spinal fusion surgery (vs. laminectomy alone) and reoperation than were patients without spondylolisthesis with a pooled odds ratio of 11.5 (95% confidence interval, 4.5-29.1; P < 0.0001) and 2.0 (95% confidence interval, 0.9-4.2; P= 0.088), respectively. Patients with a combination of synovial cysts and degenerative spondylolisthesis are more likely to undergo spinal fusion surgery than laminectomy alone compared with patients with synovial cysts and no preoperative spondylolisthesis. Furthermore, patients with synovial cysts and spondylolisthesis are more likely to require additional fusion surgery. The results from the present review lend credence to the argument that synovial cyst herniation might be a manifestation of an unstable spinal level.

Spondylolisthesis adjacent to a cervical disc arthroplasty does not increase the risk of adjacent level degeneration.

To understand whether a spondylolisthesis in the sub-axial spine cranial to a cervical disc arthroplasty (CDA) construes a risk of adjacent level disease (ALD). A retrospective review of 164 patients with a minimum 5-year follow-up of a cervical disc arthroplasty was performed. Multi-level surgeries, including hybrid procedures, were included. Multiple implant types were included. The two inter-vertebral discs (IVD) cranial of the CDA were monitored for evidence of radiologic degeneration using the Kettler criteria. The rate of ALD in CDA found in this series was 17.8%, with most affecting the immediately adjacent IVD (27.4 and 7.6%, respectively p = 0.000). Pre-operative mild spondylolisthesis adjacent to a planned CDA was not found to be a risk factor for ALD within 5years. Those with a degenerative spondylolisthesis are at higher risk of ALD (33%) than those with a non-degenerative cause for their spondylolisthesis (11%). Post-operative CDA alignment, ROM or induced spondylolisthesis do not affect the rate of ALD in those with an adjacent spondylolisthesis. Patients with ALD experience significantly worse 5-year pain and functional outcomes than those unaffected by ALD. A pre-operatively identified mild spondylolisthesis in the sub-axial spine cranially adjacent to a planned CDA is not a risk factor for ALD within 5years. These slides can be retrieved under Electronic Supplementary Material.

Lumbar ganglion cyst: Nosology, surgical management and proposal of a new classification based on 34 personal cases and literature review.

AIMTo analyze different terms used in literature to identify lumbar extradural cysts and propose a common scientific terminology; to elaborate a new morphological classification of this pathology, useful for clinical and surgical purposes; and to describe the best surgical approach to remove these cysts, in order to avoid iatrogenic instability or treat the pre-existing one.METHODSWe retrospectively reviewed 34 patients with symptomatic lumbar ganglion cysts treated with spinal canal decompression with or without spinal fixation. Microsurgical approach was the main procedure and spinal instrumentation was required only in case of evident pre-operative segmental instability.RESULTSThe complete cystectomy with histological examination was performed in all cases. All patients presented an improvement of clinical conditions, evaluated by Visual Analogic Scale and Japanese Orthopaedic Association scoring.CONCLUSIONSpinal ganglion cysts are generally found in the lumbar spine. The treatment of choice is the microsurgical cystectomy, which generally does not require stabilization. The need for fusion must be carefully evaluated: Pre-operative spondylolisthesis or a wide joint resection, during the operation, are the main indications for spinal instrumentation. We propose the terms “ganglion cyst” to finally identify this spinal pathology and for the first time its morphological classification, clinically useful for all specialists.

Iatrogenic spondylolisthesis following laminectomy for degenerative lumbar stenosis: systematic review and current concepts.

OBJECT Decompression without fusion for degenerative lumbar stenosis is an effective treatment for both the pain and disability of neurogenic claudication. Iatrogenic instability following decompression may require further intervention to stabilize the spine. The authors review the incidence of postsurgical instability following lumbar decompression, and assess the impact of surgical technique as well as study design on the incidence of instability. METHODS A comprehensive literature search was performed to identify surgical cohorts of patients with degenerative lumbar stenosis, with and without preexisting spondylolisthesis, who were treated with laminectomy or minimally invasive decompression without fusion. Data on patient characteristics, surgical indications and techniques, clinical and radiographic outcomes, and reoperation rates were collected and analyzed. RESULTS A systematic review of 24 studies involving 2496 patients was performed, assessing both open laminectomy and minimally invasive bilateral canal enlargement. Postoperative pain and functional outcomes were similar across the various studies, and postoperative radiographie instability was seen in 5.5% of patients. Instability was seen more frequently in patients with preexisting spondylolisthesis (12.6%) and in those treated with open laminectomy (12%). Reoperation for instability was required in 1.8% of all patients, and was higher for patients with preoperative spondylolisthesis (9.3%) and for those treated with open laminectomy (4.1%). CONCLUSIONS Instability following lumbar decompression is a common occurrence. This is particularly true if decompression alone is selected as a surgical approach in patients with established spondylolisthesis. This complication may occur less commonly with the use of minimally invasive techniques; however, larger prospective cohort studies are necessary to more thoroughly explore these findings.

Stand-alone anterior lumbar interbody fusion for treatment of degenerative spondylolisthesis

We sought to evaluate the clinical and radiologic efficacy of stand-alone anterior lumbar interbody fusion (ALIF) for low grade degenerative spondylolisthesis, the favoured surgical management approach at our institution. The optimal approach for surgical management of spondylolisthesis remains contentious. We performed a prospective analysis of all consecutive patients with low grade lumbar spondylolisthesis who underwent ALIF between 2009 and 2013 by a single surgeon (n=27). The mean age was 64.9years with a male to female ratio of 14:13. There were 32 levels operated and the average preoperative spondylolisthesis was 14.8%, which reduced to 6.4% postoperatively and 9.4% at the latest follow-up (p=0001). Postoperative disc height was increased to 175% of preoperative values and was statistically significant (p<0.001) and remained improved with an overall change of 139% at the latest follow-up. The radiological fusion rate was 91%. The 12-Item Short Form Health Survey (SF-12) mental and physical component summary improved from 31.7 to 43.0 (p=0.007) and from 35.4 to 51.7 (p=0.0026), respectively. The mean visual analogue scale pain score improved from 7.6 to 2.2 (p<0.001), and the mean Oswestry disability index improved from 56.9 to 17.8% (p<0.0001). The overall clinical success rate was 93%. The posterior disc height correlated with spondylolisthesis reduction (p=0.04) and the only clinical factor affecting reduction was body mass index (p=0.04). The present study provides encouraging short term results for stand-alone ALIF as a procedure for low grade lumbar degenerative spondylolisthesis. Future studies should include adequately powered, prospective, multicentre registry studies with long term follow-up to allow a better assessment of the relative benefits and risks.

Minimally invasive laminectomy for lumbar spinal stenosis in patients with and without preoperative spondylolisthesis: clinical outcome and reoperation rates.

Surgical decompression is the intervention of choice for lumbar spinal stenosis (LSS) when nonoperative treatment has failed. Standard open laminectomy is an effective procedure, but minimally invasive laminectomy through tubular retractors is an alternative. The aim of this retrospective case series was to evaluate the clinical and radiographic outcomes of this procedure in patients who underwent LSS and to compare outcomes in patients with and without preoperative spondylolisthesis. Patients with LSS without spondylolisthesis and with stable Grade I spondylolisthesis who had undergone minimally invasive tubular laminectomy between 2004 and 2011 were included in this analysis. Demographic, perioperative, and radiographic data were collected. Clinical outcome was evaluated using the Oswestry Disability Index (ODI) and visual analog scale (VAS) scores, as well as Macnab's criteria. Among 110 patients, preoperative spondylolisthesis at the level of spinal stenosis was present in 52.5%. At a mean follow-up of 28.8 months, scoring revealed a median improvement of 16% on the ODI, 2.75 on the VAS back, and 3 on the VAS leg, compared with the preoperative baseline (p < 0.0001). The reoperation rate requiring fusion at the same level was 3.5%. Patients with and without preoperative spondylolisthesis had no significant differences in their clinical outcome or reoperation rate. Minimally invasive laminectomy is an effective procedure for the treatment of LSS. Reoperation rates for instability are lower than those reported after open laminectomy. Functional improvement is similar in patients with and without preoperative spondylolisthesis. This procedure can be an alternative to open laminectomy. Routine fusion may not be indicated in all patients with LSS and spondylolisthesis.

Minimally Invasive Laminectomy for Lumbar Spinal Stenosis in Patients with and without Preoperative Spondylolisthesis: Clinical Outcome and Reoperation Rate

Introduction Surgical decompression is the intervention of choice for lumbar spinal stenosis (LSS) when nonoperative treatment has failed. Standard open laminectomy is an effective procedure. Minimally invasive laminectomy through tubular retractors is an alternative procedure. The aim of our cohort study was to evaluate the clinical and radiographic outcome of this procedure in LSS patients with or without preoperative spondylolisthesis. Materials and Methods Patients with LSS without spondylolisthesis and with stable spondylolisthesis who underwent MIS tubular laminectomy between 2004 and 2011 were included. Demographic, perioperative, and radiographic data were collected. Clinical outcome was evaluated by Oswestry disability index (ODI) and visual analog scale (VAS) scores, as well as by MacNab criteria. Results In a total of 110 patients, preoperative spondylolisthesis at the level of spinal stenosis was present in 52.5%. ODI and VAS pain scores at a mean follow-up of 28.8 months revealed a median improvement of 16% in ODI, 2.75 in VAS back, and 3 in VAS leg scores, compared with the preoperative baseline ( p &lt; 0.0001). The reoperation rate requiring fusion was 3.5%. Patients with and without preoperative spondylolisthesis had no significant differences in their clinical outcome or the reoperation rate. Conclusion MIS laminectomy is an effective procedure for treatment of LSS. Reoperation rates for instability are lower than reported after open laminectomy. Functional improvement is similar in patients with and without preoperative spondylolisthesis. This procedure can be a viable alternative to open laminectomy. Routine fusion may not be indicated in all patients with LSS and spondylolisthesis. Disclosure of Interest None declared

Does fusion improve the outcome after decompressive surgery for lumbar spinal stenosis?

Whether to combine spinal decompression with fusion in patients with symptomatic lumbar spinal stenosis remains controversial. We performed a cohort study to determine the effect of the addition of fusion in terms of patient satisfaction after decompressive spinal surgery in patients with and without a degenerative spondylolisthesis. The National Swedish Register for Spine Surgery (Swespine) was used for the study. Data were obtained for all patients in the register who underwent surgery for stenosis on one or two adjacent lumbar levels. A total of 5390 patients fulfilled the inclusion criteria and completed a two-year follow-up. Using multivariable models the results of 4259 patients who underwent decompression alone were compared with those of 1131 who underwent decompression and fusion. The consequence of having an associated spondylolisthesis in the operated segments pre-operatively was also considered. At two years there was no significant difference in patient satisfaction between the two treatment groups for any of the outcome measures, regardless of the presence of a pre-operative spondylolisthesis. Moreover, the proportion of patients who required subsequent further lumbar surgery was also similar in the two groups. In this large cohort the addition of fusion to decompression was not associated with an improved outcome.