Decompression For Lumbar Stenosis Research Articles

Polytomous Rasch Analyses of Surgeons' Decision-Making on Choice of Procedure in Endoscopic Lumbar Spinal Stenosis Decompression Surgeries.

With the growing prevalence of lumbar spinal stenosis, endoscopic surgery, which incorporates techniques such as transforaminal, interlaminar, and unilateral biportal (UBE) endoscopy, is increasingly considered. However, the patient selection criteria are debated among spine surgeons. This study used a polytomous Rasch analysis to evaluate the factors influencing surgeon decision-making in selecting patients for endoscopic surgical treatment of lumbar spinal stenosis. A comprehensive survey was distributed to a representative sample of 296 spine surgeons. Questions encompassed various patient-related and clinical factors, and responses were captured on a logit scale graphically displaying person-item maps and category probability curves for each test item. Using a Rasch analysis, the data were subsequently analyzed to determine the latent traits influencing decision-making. The Rasch analysis revealed that surgeons' preferences for transforaminal, interlaminar, and UBE techniques were easily influenced by comfort level and experience with the endoscopic procedure and patient-related factors. Harder-to-agree items included technological aspects, favorable clinical outcomes, and postoperative functional recovery and rehabilitation. Descriptive statistics suggested interlaminar as the best endoscopic spinal stenosis decompression technique. However, logit person-item analysis integral to the Rasch methodology showed highest intensity for transforaminal followed by interlaminar endoscopic lumbar stenosis decompression. The UBE technique was the hardest to agree on with a disordered person-item analysis and thresholds in category probability curve plots. Surgeon decision-making in selecting patients for endoscopic surgery for lumbar spinal stenosis is multifaceted. While the framework of clinical guidelines remains paramount, on-the-ground experience-based factors significantly influence surgeons' selection of patients for endoscopic lumbar spinal stenosis surgeries. The Rasch methodology allows for a more granular psychometric evaluation of surgeon decision-making and accounts better for years-long experience that may be lost in standardized clinical guideline development. This new approach to assessing spine surgeons' thought processes may improve the implementation of evidence-based protocol change dictated by technological advances was endorsed by the Interamerican Society for Minimally Invasive Spine Surgery (SICCMI), the International Society for Minimal Intervention in Spinal Surgery (ISMISS), the Mexican Spine Society (AMCICO), the Brazilian Spine Society (SBC), the Society for Minimally Invasive Spine Surgery (SMISS), the Korean Minimally Invasive Spine Society (KOMISS), and the International Society for the Advancement of Spine Surgery (ISASS).

Endoscopic lumbar stenosis decompression through uniportal bilateral approach

Endoscopic lumbar stenosis decompression through uniportal bilateral approach

Ambulatory uniportal versus biportal endoscopic unilateral laminotomy with bilateral decompression for lumbar spinal stenosis-cohort study using a prospective registry.

Endoscopic spine surgery has been established as a practical, minimally invasive technique for decompression in patients with lumbar spinal stenosis. However, there remains a paucity of studies prospective cohort study comparing uniportal lumbar endoscopic unilateral laminotomy with bilateral decompression and unilateral biportal endoscopic unilateral laminotomy with bilateral decompression with open spinal decompression-both viable techniques with satisfactory clinical outcomes in the treatment of lumbar spinal stenosis. To compare the efficacy of UPE and BPE lumbar decompression surgery for patients with lumbar spinal stenosis. A prospective registry of patients who had undergone spinal decompression for lumbar stenosis via UPE or BPE under a single fellowship trained spine surgeon was studied. Baseline characteristics, initial clinical presentation, and operative details including complications were recorded for all included patients. Clinical outcomes, such as visual analogue scale and Oswestry Disability Index, were recorded at preoperative, immediate postoperative, 2-week, 3-, 6-, and 12-month follow-up periods. A total of 62 patients underwent endoscopic decompression surgery for lumbar spinal stenosis (29 UPE, 33 BPE). No significant baseline differences were found between uniportal and biportal decompression, when comparing operative duration (130 vs. 140min; p = 0.30), intraoperative blood loss (5.4 vs. 6mLs; p = 0.05), and length of hospital stay (23.6 vs. 20.3h; p = 0.35). Two patients (7%) who underwent uniportal endoscopic decompression required conversion to open surgery due to inadequate decompression. Intraoperative complication rates were significantly higher in the UPE group (13.4% vs. 0%, p < 0.05). VAS score (leg & back) and ODI improved significantly (p < 0.001) in both endoscopic decompression groups across all follow-up time points, with no appreciable statistical differences between both groups. UPE has the same efficacy as BPE in the treatment of lumbar spinal stenosis. While UPE surgery enjoys added aesthetic benefits of only one wound, BPE had potentially lower risks of intraoperative complication, inadequate decompression, and conversion to open surgery during early period of learning curve.

Indications, Contraindications, and Complications of Biportal Endoscopic Decompressive Surgery for the Treatment of Lumbar Stenosis: A Systematic Review

Biportal endoscopic spine surgery is gaining popularity in managing degenerative lumbar diseases and has optimal indications and contraindications. The perioperative complications related to the biportal endoscopic approach affect the postoperative outcomes. Therefore, this study aimed to review the indications, contraindications, and complications of biportal endoscopic decompression for lumbar stenosis. For this systematic review, articles on biportal endoscopic decompressive surgery for lumbar stenosis, including central, lateral recess and foraminal stenoses, were searched for and reviewed. Additionally, the complications, indications, and contraindications of biportal endoscopic surgery for lumbar stenosis were reviewed. Forty-one articles were included in this study. The indications for biportal endoscopic decompression are central lumbar stenosis, central stenosis with lipomatosis, lateral recess stenosis, foraminal stenosis, and the far-out syndrome. The contraindications include trauma, infection, tumor, instability, high-grade spondylolisthesis, isthmic spondylolisthesis, and severe scoliosis. Perioperative complications are typically minor; major complications include durotomy, epidural hematoma, incomplete decompression, infection, facet joint injury, neural injury, increased epidural pressure, and postoperative instability. Favorable indications for a biportal endoscopic approach are central lumbar, lateral recess, foraminal, extraforaminal stenoses, and the Bertolotti syndrome. Incidental durotomy and postoperative epidural hematomas are common complications of biportal endoscopic decompression.

Outcome Of Decompression in Lumbar Stenosis Using Spinous Process Splitting Approach

Outcome Of Decompression in Lumbar Stenosis Using Spinous Process Splitting Approach

Feasibility of Unilateral Approach for Bilateral Decompressive Endoscopic Spinal Surgery for Lumbar Stenosis to Improve Back and Leg Pain: A Consecutive Single-Center Series of 60 Patients.

Introduction: Endoscopic surgery is one of the methods that achieve the goal of decompression while minimizing collateral tissue damage. Its efficacy and safety have been supported by numerous studies. There is a plethora of studies on lumbar stenosis regarding the outcomes and related issues in endoscopic spine surgery. However, few studies evaluated the outcome of the decompressive lumbar spine surgery. The present study aims to analyze the outcome of a unilateral approach to endoscopic surgery for lumbar stenosis using the visual analog scale (VAS), the Oswestry Disability Index (ODI), and MacNab's criteria.Methods: This is a retrospective study (level IV) conducted between January 2009 and December 2013 on 60 patients who underwent endoscopic interlaminar decompressive spine surgery (Destandau method) for lumbar degenerative spinal stenosis in the Hospital Universiti Sains Malaysia. The clinical outcome was measured pre-operatively and post-operatively for VAS: for back and leg pain, motor and sensory grading, the ODI, and MacNab's criteria. A paired t-test was used for statistical analysis.Results: The mean age of patients was 60.82 years comprising 23 males (38.3%) and 37 females (61.7%). The mean follow-up period was 30.1 months (range = 17.2–43 months). The mean operation time was 183.6 min (ranging from 124.8 to 242.4 min), and the mean blood loss was 150.18 mL (ranging from 30.82 to 269.54 mL). Post-operatively, mean hospital stay was 2.45 days (ranging from 1.34 to 3.56 days). The most frequently involved level was L4/L5 in 51 patients (52.6%), followed by L3/L4 in 19 patients (19.6%), L5/S1 in 24 patients (24.7%), and L2/L3 in three patients (3.1%). Improvement in the post-operative VAS for back and leg pain and the ODI for pre-operation and post-operation was statistically significant (p < 0.001). Conversely, the reduction in neurological status was statistically insignificant. Based on MacNab's criteria, 88.4% showed excellent to good outcomes.Conclusion: To summarize, unilateral percutaneous endoscopic spine surgery to achieve the bilateral decompression in lumbar stenosis provides excellent yet safe and effective outcomes. It improves back and leg pain and patients' function significantly.

Full-endoscopic (bi-portal or uni-portal) versus microscopic lumbar decompression laminectomy in patients with spinal stenosis: systematic review and meta-analysis.

Lumbar stenosis causes pain in the lower lumbar spine and lower extremities and reduces the patient's quality of life and walking ability. Thus, these conditions are common surgical indications for spinal stenosis. Previous reports have shown satisfactory clinical outcomes of the full-endoscopic (FE) and MI technique decompressive laminectomy for lumbar stenosis. However, they still remain controversial. We conducted a systematic review and meta-analysis to compare the postoperative outcomes between FE (bi-portal or uni-portal) and MI technique decompressive laminectomy for lumbar stenosis. We searched all comparative studies that compared postoperative outcomes (operative time, VAS for back and leg pain, ODI in 3months and last follow-up) of full-endoscopic (bi-portal or uni-portal) and microscopic technique decompressive laminectomy for lumbar stenosis from the PubMed and Scopus databases up to October 16, 2019. Nine of 1107 studies (five comparative studies and four RCT) (N = 994 patients) were eligible; all studies were included in pooling of FE and MI decompression. Five and three studies were included in pooling of bi-portal endoscopic, uni-portal endoscopic and MI decompression. All three techniques were compared in one study. Eight, nine, seven, eight, five, seven, eight and nine studies were included in pooling of VAS for back, leg, ODI in 3months and last follow-up and operative time, respectively. The UMD of VAS for back, leg, ODI in 3months and last follow-up of FE group was - 0.63 (95% CI - 1.15, - 0.12), - 0.15 (- 0.42, 0.11), - 2.06 (- 3.76, - 0.39), - 0.07 (- 0.22, 0.08), - 0.16 (- 0.29, - 0.03), - 0.20 (- 1.20, 0.81) scores and - 3.00 (- 12.25, 6.25) minutes when compared to MI in lumbar stenosis. In terms of complication, FE was lower risk of 0.62 (0.40, 0.96) times when compared to MI. After subgroup analysis, BESS had significant lower back and leg pain within 3months when compared to MI group, while uni-portal FE had significant lower leg pain in the last follow-up and complication when compared to MI group. There had no difference in ODI and operative time between two groups. FE had statistically significant lower back pain, lower leg pain and lower risk of having complications when compared to MI decompression in lumbar stenosis, while there is no difference in ODI and operative time between both groups. Comparing to MI, BESS had better early postoperative back pain while uni-portal FE had better leg pain and risk of having complications. Larger, prospective randomized controlled studies are needed to confirm these findings as the current literature is still insufficient. III.

A Review of Emerging Evidence for Utilization of a Percutaneous Interspinous Process Decompression Device to Treat Symptomatic Lumbar Adjacent-Segment Degeneration.

ObjectivePostlaminectomy syndrome diagnoses secondary to adjacent segment degeneration are a substantial and rising cause of morbidity in the United States. Emerging spinal cord neuromodulation technologies have produced successful outcomes for postlaminectomy neuropathic pain but are less effective in treating neurogenic claudication secondary to recurrent lumbar stenosis. Percutaneous interspinous process decompression systems can be used as a salvage treatment modality for persistent structural neurogenic claudication in postlaminectomy syndrome or after spinal cord stimulator implantation.MethodsThis paper is a review of emerging evidence for efficacious utilization of percutaneous interspinous process decompression.ResultsA recent pragmatic trial of subjects who underwent percutaneous interspinous process decompression for lumbar stenosis with intermittent neurogenic claudication reported that 63% (26/41) maintained minimal clinically important improvement in visual analog scale (VAS) leg pain, 61% (25/41) in VAS back pain, 78% (32/41) in function objective values, and 88% (36/41) reported satisfaction with treatment at 12 months postop. All subjects in a small case series of seven individuals with postlaminectomy adjacent-segment disease reported postoperative satisfaction scores of 3 or 4 on a 0–4 scale and were also able to decrease or wean completely off controlled pain medications. In another study, there was a significant decrease in average leg pain (60% improvement, P < 0.0001, N = 25) and axial low back pain (58% improvement, P < 0.0001, N = 25) in patients who underwent one- or two-level percutaneous interspinous process decompression as a rescue treatment for reemerging neurogenic claudication after spinal cord stimulator implantation.ConclusionsThe spine often is a focus of progressive disease. Furthermore, mechanical changes associated with spinal instrumentation can lead to additional disease at adjacent levels. Many individuals will present with symptomatic neurogenic claudication recalcitrant to multimodal management strategies, including even the most sophisticated neuromodulation technologies. Implementation of salvage percutaneous interspinus process decompression implantation in cases of adjacent segment degeneration or incomplete spinal cord stimulation can decompress structural causes of neurogenic claudication while sparing the patient from more invasive surgical reoperation techniques.

Indirect decompression of lumbar stenosis

Degenerative lumbar stenosis can lead to symptoms of neurogenic claudication and lumbar radiculopathy. Lumbar stenosis can be caused by static compression of the neural elements in the central canal, along the lateral recess, and in the neuroforamen, as well as by dynamic changes to the total area of the central canal and neuroforamen. Previously, surgical options for the treatment of degenerative lumbar stenosis were primarily based on direct posterior open decompressions and fusions. However, novel techniques of indirect decompression have now been developed that restore disc height to increase the area of the central canal and neuroforamen and address the dynamic aspect of stenosis, while avoiding the extensive soft tissue injury involved in posterior open decompressions and fusions. Interbody fusions and interspinous devices are two methods of indirect decompression that are being commonly used.In this study, we provide a broad overview of the advantages, disadvantages, indications, evidence, and complications of ALIF, LLIF, and OLIF, as well as interspinous devices including Coflex. Though there is limited comparative evidence demonstrating that one approach is superior to another in terms of clinical and radiographic outcomes, evidence does show that interbody techniques are effective at treating lumbar stenosis by increasing the total area of the central canal and neuroforamen while having high fusion rates. Though the newer generation of interspinous devices have lower failure rates than their predecessors, they still are not comparable to the interbody devices in terms of long term outcomes. The optimal approach for the indirect treatment of lumbar stenosis therefore depends on multiple variables, including but not limited to the spinal level of disease, the anatomy of the individual patient, the pathology being treated, and the familiarity of the surgeon.

Assessment of Paraspinal Muscle Cross-sectional Area After Lumbar Decompression: Minimally Invasive Versus Open Approaches.

A retrospective, blinded analysis of imaging studies. To evaluate changes in paraspinal muscle cross-sectional area (CSA) after surgical treatment for lumbar stenosis and to compare these changes between minimally invasive and standard open approaches. The open approach to lumbar stenosis is effective, but it involves retraction and resection of muscle from the spinous process, which can result in ischemia and denervation of paraspinal musculature and may lead to muscle atrophy and pain. It is hypothesized that the microendoscopic decompression of stenosis (MEDS) technique will better preserve the paraspinal muscles compared with the open procedure. A total of 18 patients underwent a 1-level posterior decompression for lumbar stenosis, (9 open, 9 MEDS). Lumbar magnetic resonance imaging was obtained before surgery and after surgery (open approach average 16.3 mo; MEDS average 16.6 mo). CSA of paraspinal muscles were averaged over the distance of the surgical site. The mean age of patients treated with the open and MEDS approaches were 55.2 and 66.4 years, respectively (P=0.07). Paraspinal muscle CSA decreased by an average of 5.4% (SD=10.6%; range, -24.5% to +7.7%) in patients treated with the open approach and increased by an average of 9.9% (SD=14.4%; range, -9.8% to +33.1%) in patients treated with MEDS (P=0.02). For the open approach, changes in CSA did not differ significantly between the left and right sides for erector spinae (P=0.35) or multifidus muscles (P=0.90). After the MEDS approach there were no significant differences between the dilated and contralateral sides with regard to change in CSA for erector spinae (P=0.85) or multifidus muscles (P=0.95). Compared with the open approach for lumbar stenosis, MEDS had significantly less negative impact on the paraspinal muscle CSA. Previous reports have documented negative effects of paraspinal muscle injury, including weakness, disability, and pain. Collectively, these data suggest that the MEDS approach for lumbar decompression is less destructive to the paraspinous muscles than the open approach and may facilitate better clinical outcomes.

Only walking matters-assessment following lumbar stenosis decompression.

Multiple outcome measures exist to evaluate the outcomes of spinal decompression surgery; however, these tend to be complex and are difficult to express to the patient pre-operatively to accurately guide their expectations. We present outcomes, in terms of walking distance measurement, of a prospective single surgeon series of 76 consecutive patients with spinal stenosis. 76 patients (mean age 68.8years; 48-91years) had decompression surgery using spinous process osteotomy. Accurate measurement of walking distance was used as an outcome measure, and factors that affect it were evaluated. Walking distance was measured pre-operatively, post-operatively and at 3months follow-up using a measuring wheel. The minimum follow-up was 5years. The mean distances walked were 78.1, 419.9 and 1285m, respectively. Pre-operative disc height (p=0.023) and male gender (p=0.039) predicted a significant improvement in walking distance, while age (p=0.23), ASA grade (p=0.39) and the number of levels operated on (p=0.89) did not significantly affect the increase in walking distance. 12 patients experienced post-operative complications (15.8%), and at last clinical follow-up (6.3years, 5.1-6.9years) 27 patients (35.5%) had residual leg symptoms and 8 had undergone further revision procedures (10.5%). This study demonstrates that walking distance is an accurate and accessible method of determining surgical outcomes.

Back pain improvement after decompression without fusion or stabilization in patients with lumbar spinal stenosis and clinically significant preoperative back pain.

OBJECTIVE The relief of leg symptoms by surgical decompression for lumbar stenosis is well supported by the literature. Less is known about the effect on back pain. Some surgeons believe that the relief of back pain should not be an expected outcome of decompression and that substantial back pain may be a contraindication to decompression only; therefore, stabilization may be recommended for patients with substantial preoperative back pain even in the absence of well-accepted indications for stabilization such as spondylolisthesis, scoliosis, or sagittal malalignment. The purpose of this study is to determine if patients with lumbar stenosis and substantial back pain-in the absence of spondylolisthesis, scoliosis, or sagittal malalignment-can obtain significant improvement after decompression without fusion or stabilization. METHODS Analysis of the National Neurosurgery Quality and Outcomes Database (N2QOD) identified 726 patients with lumbar stenosis (without spondylolisthesis or scoliosis) and a baseline back pain score ≥ 5 of 10 who underwent surgical decompression only. No patient was reported to have significant spondylolisthesis, scoliosis, or sagittal malalignment. Standard demographic and surgical variables were collected, as well as patient outcomes including back and leg pain scores, Oswestry Disability Index (ODI), and EuroQoL 5D (EQ-5D) at baseline and 3 and 12 months postoperatively. RESULTS The mean age of the cohort was 65.6 years, and 407 (56%) patients were male. The mean body mass index was 30.2 kg/m2, and 40% of patients had 2-level decompression, 29% had 3-level decompression, 24% had 1-level decompression, and 6% had 4-level decompression. The mean estimated blood loss was 130 ml. The mean operative time was 100.85 minutes. The vast majority of discharges (88%) were routine home discharges. At 3 and 12 months postoperatively, there were significant improvements from baseline for back pain (7.62 to 3.19 to 3.66), leg pain (7.23 to 2.85 to 3.07), EQ-5D (0.55 to 0.76 to 0.75), and ODI (49.11 to 27.20 to 26.38). CONCLUSIONS Through the 1st postoperative year, patients with lumbar stenosis-without spondylolisthesis, scoliosis, or sagittal malalignment-and clinically significant back pain improved after decompression-only surgery.

Outcome after Surgery of Lumbar Spinal Stenosis: A Randomized Comparison of Bilateral Laminotomy, Trumpet Laminectomy, and Conventional Laminectomy.

Laminectomy is the traditional operating method for the decompression of spinal canal stenosis. New partial decompression processes have been suggested in the treatment of lumbar stenosis. The benefit of a micro surgical approach is the chance of an extensive bilateral decompression of the spinal canal or foramen at one or numerous levels, through a minimal para-spinal muscular separation. To match the safety and the clinical consequences after a bilateral laminotomy, laminectomy and trumpet laminectomy in patients with lumbar spinal stenosis who were randomized to one of three treatment groups. Prospective study. One hundred twenty consecutive patients with 227 levels of lumbar stenosis without significant herniated discs or instability were randomized to three treatment groups [bilateral laminotomy (Group 1), laminectomy (Group 2), and trumpet laminectomy (Group 3)]. Perioperative parameters and complications were documented. Symptoms and scores, such as a visual analog scale (VAS), Oswestry Disability Index, and patient satisfaction, were assessed preoperatively at 3, 6, and 12 months after surgery. Adequate decompression was achieved in all patients on the basis of surgeon satisfaction. The global complication rate was lowest in patients who had undertaken bilateral laminotomy (Group 1). The minimum follow-up of 12 months was achieved in 100% of patients. Matched with that experience in Group 1, but, with more remaining back and leg pain was found in Group 2, 3.85 ± 0.28 and 1.60 ± 0.44, respectively and 3.24 ± 0.22 and 2.44 ± 0.26 in Group 3, respectively compared with 1.84 ± 0.28 and 1.25 ± 0.12 (Group 1) at the 1-year follow-up assessment (p < 0.05). It was the same for the ODI scores, which reached 14 ± 8% (Group 1), 28 ± 12% (Group 2), and 26 ± 16 after 12 months of surgery (Group 3) (significant, p < 0.01 compared with preoperative scores). Patient satisfaction was higher in Group 1, with 7.5, 20, and 25% of patients displeased (in Groups 1, 2, and 3, respectively; p < 0.01). Bilateral Laminotomy is certified acceptable and harmless in decompression of lumbar stenosis, causing a highly significant decrease of symptoms and disability.

Therapeutic sustainability and durability of coflex interlaminar stabilization after decompression for lumbar spinal stenosis: a four year assessment.

Approved treatment modalities for the surgical management of lumbar spinal stenosis encompass a variety of direct and indirect methods of decompression, though all have varying degrees of limitations and morbidity which potentially limit the efficacy and durability of the treatment. The coflex(®) interlaminar stabilization implant (Paradigm Spine, New York, NY), examined under a United States Food and Drug Administration (US FDA) Investigational Device Exemption (IDE) clinical trial, is shown to have durable outcomes when compared to posterolateral fusion in the setting of post-decompression stabilization for stenotic patients. Other clinical and radiographic parameters, more indicative of durability, were also evaluated. The data collected from these parameters were used to expand the FDA composite clinical success (CCS) endpoint; thus, creating a more stringent Therapeutic Sustainability Endpoint (TSE). The TSE allows more precise calculation of the durability of interlaminar stabilization (ILS) when compared to the fusion control group. A retrospective analysis of data generated from a prospective, randomized, level-1 trial that was conducted at 21 US sites was carried out. Three hundred forty-four per-protocol subjects were enrolled and randomized to ILS or fusion after decompression for lumbar stenosis with up to grade 1 degenerative spondylolisthesis. Clinical, safety, and radiographic data were collected and analyzed in both groups. Four-year outcomes were assessed, and the TSE was calculated for both cohorts. The clinical and radiographic factors thought to be associated with therapeutic sustainability were added to the CCS endpoints which were used for premarket approval (PMA). Success rate, comprised of no second intervention and an ODI improvement of ≥ 15 points, was 57.6% of ILS and 46.7% of fusion patients (p = 0.095). Adding lack of fusion in the ILS cohort and successful fusion in the fusion cohort showed a CCS of 42.7% and 33.3%, respectively. Finally, adding adjacent level success to both cohorts and maintenance of foraminal height in the coflex cohort showed a CCS of 36.6% and 25.6%, respectively. With additional follow-up to five years in the U.S. PMA study, these trends are expected to continue to show the superior therapeutic sustainability of ILS compared to posterolateral fusion after decompression for spinal stenosis. There are clear differences in both therapeutic sustainability and intended clinical effect of ILS compared to posterolateral fusion with pedicle screw fixation after decompression for spinal stenosis. There are CCS differences between coflex and fusion cohorts noted at four years post-op similar to the trends revealed in the two year data used for PMA approval. When therapeutic sustainability outcomes are added to the CCS, ILS is proven to be a sustainable treatment for stabilization of the vertebral motion segment after decompression for lumbar spinal stenosis.

Indirect Decompression of Lumbar Stenosis With Transpsoas Interbody Cages and Percutaneous Posterior Instrumentation

The minimally invasive lateral transpsoas retroperitoneal approach to address lumbar stenosis offers advantages to traditional approaches, including sparing of the AP annulus and longitudinal ligament and less risk to the peritoneal contents and retroperitoneal vascular structures. Few studies have presented longitudinal measures of radiographic indirect decompression and relief of pain and restoration of function using the lateral approach to spine fusion. We determined (1) whether radiographic measures suggestive of decompression were achieved after surgery and maintained 1 year after surgery, (2) whether the intervention resulted in sustained improvements in patient-reported outcomes scores 1 year after surgery, and (3) the frequency of pseudarthrosis on CT scans at 1 year after surgery in patients with moderate or severe lumbar stenosis treated with the approach. Between 2008 and 2012, 158 patients were surgically treated to alleviate symptoms associated with degenerative lumbar stenosis, of whom 60 (38%) were treated with lateral lumbar interbody fusion. Of these 60 patients, 36 (60%) received CT scans preoperatively and at 1-year postoperatively and were available for radiographic analysis. Of the 60 treated patients, 16 (27%) were lost to followup before 12 months, leaving the records of 44 patients available for review of patient-reported improvements in pain and return to function. Radiographic increases in disc height, foraminal area, and canal area were measured by one observer on CT scans postoperatively and at 1 year and compared to preoperative values. Patient-reported scores, including VAS pain score and Oswestry Disability Index (ODI), were collected preoperatively and at 3 and 12 months postoperatively. Increases in disc height (67%, p < 0.001), foraminal area (24%-31%, p < 0.001), and canal area (7%, p = 0.011) measured immediately postoperatively were sustained at 1-year followup. VAS pain score and ODI both improved (p < 0.001) at 3 months and were maintained at 1 year. No pseudarthroses were noted radiographically. The lateral transpsoas approach to interbody fusion is capable of sustaining indirect decompression of the neural structures and resolving preoperative claudication and radiculopathy. A larger series of patients with longer followup should be studied to substantiate these early clinical results. Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Indirect spinal decompression for lumbar stenosis

Lumbar spinal stenosis continues to be an important cause of low back pain and neurogenic claudication. As the population ages and life expectancy increases, both the incidence and prevalence of spinal stenosis will present a significant challenge to spine surgeons. Both interspinous and interbody fusion techniques have demonstrated the ability to decrease low back pain and provide clinically significant pain relief from neurogenic claudication through indirect means. While direct decompression of the spine has been well documented in the literature and the gold standard, new interest in minimally invasive techniques and indirect decompression has led to new devices and clinical studies with promising results.

Commentary: The sedimentation sign: correlation with operative level in patients undergoing lumbar decompression for spinal stenosis

Fazal A, Yoo A, Bendo JA. Does the presence of the nerve root sedimentation sign on MRI correlate with the operative level in patients undergoing posterior lumbar decompression for lumbar stenosis? Spine J 2013;13:837-42 (in this issue).

Does the presence of the nerve root sedimentation sign on MRI correlate with the operative level in patients undergoing posterior lumbar decompression for lumbar stenosis?

Background contextRecent research describes the use of a nerve root sedimentation sign to diagnose lumbar spinal stenosis (LSS). The lack of sedimentation of the nerve roots (positive sedimentation sign) to the dorsal part of the dural sac is the characteristic feature of this new radiological parameter. PurposeTo demonstrate how the nerve root sedimentation sign compares with other more traditional radiological parameters in patients who have been operated for LSS. Study design/settingA retrospective chart and image review. Patient samplePreoperative magnetic resonance images (MRIs) were reviewed from 71 consecutive operative patients who presented with LSS and received spinal decompression surgery from 2006 to 2010. Outcome measuresPreoperative T2-weighted MRIs were reviewed for each patient. MethodsOne hundred thirty-four vertebral levels from L1 to L5 were measured for: sedimentation sign, cross-sectional area (CSA) and anterior/posterior (A/P) diameter of the dural sac, thickness of the ligamentum flavum, and Fujiwara grade of facet hypertrophy. Radiological measurements were made using Surgimap 1.1.2.169 software (Nemaris, Inc., New York, NY, USA). Statistical analyses were performed using the SPSS 17.0 statistical software (SPSS Inc., Chicago, IL, USA). Significance was demonstrated using unpaired t tests and chi-squared tests. Study funding was departmental. There were no study-specific conflicts of interest–associated biases. ResultsA positive sedimentation sign was determined in 120 operated levels (89.5%), whereas 14 levels (10.5%) had no sign (negative sedimentation sign). The mean CSA and A/P diameter were 140.62 mm2 (standard deviation [SD]=53) and 11.76 mm (SD=3), respectively, for the no-sign group; the mean CSA and A/P diameter were 81.87 mm2 (SD=35) and 8.76 mm (SD=2.2), respectively, for the sedimentation sign group (p<.001). We found that 60% of levels with Fujiwara Grade A facet hypertrophy did not have a sedimentation sign, whereas 86.3% of levels with Grade B, 93.2% of levels with Grade C, and 100.0% of levels with Grade D did have a sedimentation sign (p<.001). ConclusionsThe sedimentation sign is a new measurement tool that can enable physicians to objectively assess and quantify spinal stenosis. The sign is most often present in patients who have clinically significant lumbar stenosis and require surgery.

Comparison of minimally invasive fusion and instrumentation versus open surgery for severe stenotic spondylolisthesis with high-grade facet joint osteoarthritis

The object of this study was to compare minimally invasive surgery (MIS) with open surgery in a severely affected subgroup of degenerative spondylolisthetic patients with severe stenosis (SDS) and high-grade facet osteoarthritis (FJO). From January 2009 to February 2010, 49 patients with severe SDS and high-grade FJO were treated using either MIS or open TLIF. Intraoperative and diagnostic data, including perioperative complications and length of hospital stay (LOS), were collected, using retrospective chart review. Surgical short- and long-term outcomes were assessed according to the Oswestry disability index (ODI) and visual analog scale (VAS) for back and leg pain. Comparing MIS and open surgery, the MIS group had lesser blood loss, significantly lesser need for transfusion (p = 0.02), more rapid improvement of postoperative back pain in the first 6 weeks of follow-up and a shorter LOS. On the other hand, we experienced in the MIS group a longer operative time. The distribution on the postoperative ODI (p = 0.841), VAS leg (p = 0.943) and back pain (p = 0.735) scores after a mean follow-up of 2 years were similar. The overall proportion of complications showed no significant difference between the groups (29% in the MIS group vs. 28% in the open group, p = 0.999). Minimally invasive surgery for severe SDS leads to adequate and safe decompression of lumbar stenosis and results in a faster recovery of symptoms and disability in the early postoperative period.

Preliminary Results of Minimally Invasive Decompression, TLIF and Percutaneous Pedicle Screw Insertion in Stenotic Spondylolisthesis with Severe Facet Joint Osteoarthritis

Object: Minimally invasive spine (MIS) procedures are increasingly being recognized as equivalent to open procedures with regard to clinical and radiographic outcomes. These techniques are also believed to result in less pain and disability in the immediate postoperative period. There are, however, little data to assess whether these procedures in combination with minimally invasive transforaminal interbody fusion (MI-TLIF) and percutaneous pedicle screw insertion are effective in complex cases of stenotic degenerative spondylolisthesis with severe facet joint osteoarthritis (FJO). Methods: This study retrospectively reviewed all patients who underwent lumbar instrumentation, fusion and decompression for degenerative spondylolisthesis with severe stenosis and facet joint osteoarthritis (FJO) between June 2010 and June 2011. Blood loss, operative time and intraoperative complications were assessed in all surgically treated patients who were treated with MIS decompression, MI-TLIF and percutaneous transpedicular instrumentation. Clinical outcome was measured using the Oswestry Disability Index (ODI) and Visual Analogue Scale (VAS) for back pain, leg pain, and activity level. Satisfaction was assessed with VAS for satisfaction. Radiological follow-up includes x-ray films, computed tomography and in some cases magnetic tomography scan. Results: Twenty four cases with severe stenotic changes accompanied by severe FJO were treated with minimally invasive procedure. The minimum follow-up was 6 months with a mean of 8 months. The mean preoperative ODI score was 46.8, decreasing to a mean of 23 postoperatively. The mean VAS leg and back pain scores were 67.5 improving to means of 25.8. Twenty one out of 24 cases experienced a clinical benefit according to VAS for satisfaction and ODI. Complications included wound healing disturbance (4%), CSF fistula (4%) and contralateral radiculopathy due to articular bone spurs (8%). The accuracy of pedicle screws was high and only one revision surgery was performed. Conclusion: MIS for severe stenotic spondylolisthesis leads to adequate and safe decompression of lumbar stenosis and results in a highly significant reduction of symptoms and disability. MIS-TLIF and percutaneous pedicle screw insertion constitute a promising treatment alternative for patients with severe stenosis and facet joint osteoarthritis.