Surgery For Spinal Stenosis Research Articles

Development of a Machine-Learning Model of Short-Term Prognostic Prediction for Spinal Stenosis Surgery in Korean Patients.

Background: In this study, based on machine-learning technology, we aim to develop a predictive model of the short-term prognosis of Korean patients who received spinal stenosis surgery. Methods: Using the data obtained from 112 patients with spinal stenosis admitted at N hospital from February to November, 2019, a predictive analysis was conducted for the pain index, reoperation, and surgery time. Results: Results show that the predicted area under the curve was 0.803, 0.887, and 0.896 for the pain index, reoperation, and surgery time, respectively, thereby indicating the accuracy of the model. Conclusion: This study verified that the individual characteristics of the patient and treatment characteristics during surgery enable a prediction of the patient prognosis and validate the accuracy of the approach. Further studies should be conducted to extend the scope of this research by incorporating a larger and more accurate dataset.

Design of a robot-assisted system for transforaminal percutaneous endoscopic lumbar surgeries: study protocol

BackgroundTransforaminal percutaneous endoscopic lumbar surgeries (PELS) for lumbar disc herniation and spinal stenosis are growing in popularity. However, there are some problems in the establishment of the working channel and foraminoplasty such as nerve and blood vessel injuries, more radiation exposure, and steeper learning curve. Rapid technological advancements have allowed robotic technology to assist surgeons in improving the accuracy and safety of surgeries. Therefore, the purpose of this study is to develop a robot-assisted system for transforaminal PELS, which can provide navigation and foraminoplasty.MethodsThe robot-assisted system consists of three systems: preoperative planning system, navigation system, and foraminoplasty system. In the preoperative planning system, 3D visualization of the surgical segment and surrounding tissues are realized using the multimodal image fusion technique of computed tomography and magnetic resonance imaging, and the working channel planning is carried out to reduce the risk for injury to vital blood vessels and nerves. In the navigation system, the robot can obtain visual perception ability from a visual receptor and automatically adjust the robotic platform and robot arm to the appropriate positions according to the patient’s position and preoperative plan. In addition, the robot can automatically register the surgical levels through intraoperative fluoroscopy. After that, the robot will provide navigation using the 6 degree-of-freedom (DOF) robot arm according to the preoperative planning system and guide the surgeon to complete the establishment of the working channel. In the foraminoplasty system, according to the foraminoplasty planning in the preoperative planning system, the robot performs foraminoplasty automatically using the high speed burr at the end of the robot arm. The system can provide real-time feedback on the working status of the bur through multi-mode sensors such as multidimensional force, position, and acceleration. Finally, a prototype of the system is constructed and performance tests are conducted.DiscussionOur study will develop a robot-assisted system to perform transforaminal PELS, and this robot-assisted system can also be used for other percutaneous endoscopic spinal surgeries such as interlaminar PELS and percutaneous endoscopic cervical and thoracic surgeries through further research. The development of this robot-assisted system can be of great significance. First, the robot can improve the accuracy and efficiency of endoscopic spinal surgeries. In addition, it can avoid multiple intraoperative fluoroscopies, minimize exposure to both patients and the surgical staff, shorten the operative time, and improve the learning curve of beginners, which is beneficial to the popularization of percutaneous endoscopic spinal surgeries.

Clinical Implications of the Epidural Fat Thickness in the Management of Lumbar Spinal Stenosis

Lumbar epidural lipomatosis is a rare condition defined as the excessive accumulation of epidural fat (EF). We herein investigated the indicators of the posterior compression factors, EF and yellow ligament, to identify the clinical features of lumbar epidural lipomatosis. Five hundred consecutive patients who underwent posterior lumbar decompression surgery for lumbar spinal stenosis (LSS) were retrospectively reviewed. The EF/SC-L index (the ratio of the anteroposterior length of the EF to that of the spinal canal [SC]) was evaluated at the spinal level that exhibited maximum dural tube compression. The participants were divided into 3 groups: grade I, EF/SC-L index ≤50%; grade II, EF/SC-L index 51%-74%; grade III, EF/SC-L index ≥75%. EF/SC-A (the ratio of the cross-sectional area of EF to that of SC) and YL/SC-A (the ratio of the cross-sectional area of yellow ligament [YL] to that of SC) were calculated. The clinical outcomes were assessed according to the Japan Orthopaedic Association scale for lumbar disease. EF/SC-L exhibited a significantly positive correlation with EF/SC-A (r= 0.82, P < 0.001), and a negative correlation with YL/SC-A (r=-0.71, P < 0.001). The Japan Orthopaedic Association score recovery rate was 56.7 ± 22.6 in the case-matched control group, 34.5 ± 31.2 in the grade II group (P < 0.001), and 39.6 ± 24.9 in the grade III group (P=0.032). The EF/SC-L index is a simple and reliable indicator to quantitatively evaluate posterior compression in patients with LSS. As the accumulation ofEF is associated with worse operative outcomes, the EF/SC-L index should be considered when planning lumbar decompression surgery for patients with LSS.

Does the order of total hip replacement and lumbar spinal stenosis surgery influence patient-reported outcomes: An observational register study.

Patients with degenerative hip and lumbar spine disorders requiring surgery in both locations is fairly common in clinical practice. We investigated if the order of total hip replacement (THR) and lumbar spinal stenosis surgery (LSSS) influences patient-reported outcomes (PROs). We used data from the Swedish Hip Arthroplasty Register (SHAR) and the Swedish Spine Register (Swespine), on patients operated with THR and LSSS in years 2002 to 2012. To increase the probability of having symptomatic disorders in both locations at the time of the first surgery, we only included patients with both LSSS and THR performed within 2 years. Linear and logistic regression analyses adjusted for age, sex, preoperative PROs, and time between surgeries were used to investigate the association between order of surgeries and the generic PRO measurements EQ-5D and EQ VAS. Eighty-four patients had THR prior to LSSS and 171 patients LSSS prior to THR. Linear regression showed that LSSS prior to THR was associated with higher EQ-5D index (B = 0.09, 95% confidence interval [CI] 0.03-0.16) and EQ VAS (B = 5.6, 95% CI 0.4-10.9) 1 year after the last surgery. Logistic regression showed that the odds ratio [OR] for not having any problems in the "pain" (OR = 3.0, 95% CI 1.5-6.3) and "anxiety/depression" (OR = 2.3, 95% CI 1.3-4.1) dimensions were higher for LSSS before THR. In our cohort, LSSS before THR was associated with better health-related quality of life outcomes compared to the reverse order. The results from our cohort can be helpful in a clinical situation where the physician gives advice to an individual patient when choosing the order of procedures. However, further studies are necessary in order to confirm these results in other cohorts. At present, standard of care remains that order of surgery should be individualized for each patient, with guidance from the operating surgeons.

Surgery versus non-surgical treatment for lumber spinal stenosis: A comparative study

Background: Surgery for lumbar spinal stenosis remains an option for patients with persistent and severe symptoms that include both back and leg pain. In contrast, in nonsurgical treatment surgeons were encouraged to recommend active physical therapy (PT), education or counseling with home exercise instruction, and nonsteroidal anti-inflammatory medication. The present study was conducted to compare surgery versus non surgical treatment for lumber spinal stenosis. Material and Methods: The present study was conducted to compare surgery versus non surgical treatment for lumber spinal stenosis. Patients were randomly divided into two treatment groups; 1) surgical decompression or 2) physical therapy. The study was then fully explained to the subjects, after which they would be randomly assigned to have surgery or attend physical therapy. The Group I was patients with surgical treatment and Group II was patients with physical therapy. The primary outcome for the study was the Physical Function score on the Medical Outcomes Survey Short Form 36 (SF-36) at baseline, 10 weeks, 26 weeks. All analyses were conducted in SAS version 9.3.Results: In the present study total sample size was 120 subjects per group, with a 50% split by gender (60 subjects per group). The mean age of surgery group was 64.8 and of physical therapy were 68.9. Maximum patients in both groups had no prior back surgeries for the same spinal segment. Baseline Mean changes in physical function for the surgery and PT groups were 25.9 and 28.8 respectively. 10 weeks Mean changes in physical function for the surgery and PT groups were 43.7 and 40.4 respectively. 26 weeks Mean changes in physical function for the surgery and PT groups were 48.1 and 46.5 respectively. Results showed that participants in both groups began to improve at 10 weeks; continued to improve through 26 weeks. Conclusion: The present study concluded that patients began to show improvement at the 10 week mark, continued to improve through 26 weeks of the study.

Factors of Adjacent Segment Disease Onset After Microsurgical Decompression for Lumbar Spinal Canal Stenosis

Few studies have examined the underlying cause of adjacent segment disease (ASD) after decompression surgery for lumbar spinal stenosis. The goal of this study is to investigate factors related to the onset of ASD after decompression surgery based on the imaging results. We examined 95 patients who underwent single-level decompression for lumbar spinal stenosis (L3/4, L4/5) and follow-up for 5 or more years. Radiographic images were performed preoperatively and at each year of follow-up. We then examined image parameters by focusing on the level operated on and adjacent segments in relation to the postoperative onset of symptomatic ASD. During the mean observation period of 7.5 years, 39 of 95 patients developed symptomatic ASD. Patients with a high preoperative sagittal rotation angle in adjacent segments possibly developed postoperative ASD (P= 0.0006). Furthermore, postoperative ASD tended to be unlikely in patients who exhibited postoperative slip progression at the operated level (P= 0.025). Based on receiver operating characteristic analysis, ASD developed with a probability of 91.3% in patients with a preoperative sagittal rotation angle of ≥7.5° in adjacent segments when there was no postoperative slip progression at the operated level. However, ASD developed in only 16.7% of patients with a preoperative adjacent segment sagittal rotation angle of 7.5° or less when there was postoperative slip progression at the operated level. Biomechanical changes at the operated level and adjacent segments contribute to the onset of ASD after lumbar decompression. Preoperative high sagittal rotation angle of adjacent segments and negative postoperative slip progression at the operated level are risk factors of ASD.

Outcomes after spinal stenosis surgery by type of surgery in adults aged 60 years and older.

Mobility disability due to spinal stenosis is common in the senior population and often surgery is warranted for patients with severe symptoms and neurological dysfunction. However, although current clinical guidelines recommend stabilisation surgery in addition to decompression in patients with spinal stenosis and instability due to degenerative spondylolisthesis, the relationship between outcomes and the specific type of surgery have not been well studied. We therefore assessed the postoperative recovery timeline for 12 months and compared patient-reported outcomes dependent on the extent of decompression and additional stabilisation among seniors undergoing spinal stenosis surgery. We investigated 457 patients (mean age 76.0 &plusmn; 10.7 years, 58% women) from a consecutive cohort prior to spinal stenosis surgery. Follow-up was at 3 or 6months and at 12 months postoperatively. At each visit, pain, neurological dysfunction and disability were assessed using the North American Spine Society questionnaire. Repeated-measures analysis compared outcomes by type of surgery adjusting for baseline symptoms, gender, age, number of comorbidities, centre and year of surgery. Most improvement occurred within the first 3 to 6 months with little or no further improvement at 12 months. Over 12 months and in adjusted models, patients receiving one-segment versus multi-segment decompression experienced significantly greater reduction of pain (&minus;49.2% vs &minus;41.9%, p = 0.013) and neurological dysfunction (&minus;37.1% vs &minus;25.9%, p &lt;0.0001), but only borderline greater reduction of disability (&minus;32.7% vs &minus;28.2%, p = 0.051). Moreover, reduction in pain and neurological function did not differ with or without additional stabilisation and extend of decompression. However, patients who received one-segment (&minus;28.9%) or multi-segment (&minus;28.3%) stabilisation experienced significantly less reduction in disability after surgery compared with those who were not stabilised (&minus;34.1%, p &lt;0.043). Among senior patients undergoing spinal stenosis surgery, recovery was largely complete by 3 to 6 months after surgery and differed little by type of surgery independently of symptoms prior to surgery and other covariates. However we could document a trend toward more improvement in particularly neurological dysfunction and disability with less invasive surgery.

Comparative Effectiveness of Microdecompression Alone vs Decompression Plus Instrumented Fusion in Lumbar Degenerative Spondylolisthesis

Conflicting evidence and large practice variation are present in the surgical treatment of degenerative spondylolisthesis. More than 90% of surgical procedures in the United States include instrumented fusion compared with 50% or less in other countries. To evaluate whether the effectiveness of microdecompression alone is noninferior to decompression with instrumented fusion in a real-world setting. This multicenter comparative effectiveness study with a noninferiority design assessed prospective data from the Norwegian Registry for Spine Surgery. From September 19, 2007, to December 21, 2015, 1376 patients at 35 Norwegian orthopedic and neurosurgical departments underwent surgery for lumbar spinal stenosis with degenerative spondylolisthesis without scoliosis. After excluding patients undergoing laminectomy alone, fusion without instrumentation, or surgery in more than 2 levels and those with a former operation at the index level, 794 patients were included in the analyses, regardless of missing or incomplete follow-up data, before propensity score matching. Data were analyzed from March 20 to October 30, 2018. Microdecompression alone or decompression with instrumented fusion. A reduction from baseline of 30% or greater in the Oswestry Disability Index at 12-month follow-up. After propensity score matching, 570 patients (413 female [72%]; mean [SD] age, 64.7 [9.5] years) were included for comparison, with 285 undergoing microdecompression (mean [SD] age, 64.6 [9.8] years; 205 female [72%]) and 285 undergoing decompression with instrumented fusion (mean [SD] age, 64.8 [9.2] years; 208 female [73%]). The proportion of each type of procedure varied between departments. However, changes in outcome scores varied within patients but not between departments. The proportion of patients with improvement in the Oswestry Disability Index of at least 30% was 150 of 219 (68%) in the microdecompression group and 155 of 215 (72%) in the instrumentation group. The 95% CI (-12% to 5%) for the difference of -4% was above the predefined margin of noninferiority (-15%). Microdecompression alone was associated with shorter operation time (mean [SD], 89 [44] vs 180 [65] minutes; P < .001) and shorter hospital stay (mean [SD], 2.5 [2.4] vs 6.4 [3.0] days; P < .001). Among patients with degenerative spondylolisthesis, the clinical effectiveness of microdecompression alone was noninferior to that of decompression with instrumented fusion. Microdecompression alone was also associated with shorter durations of surgery and hospital stay, supporting the suggestion that the less invasive procedure should be considered for most patients.

55. Early deformity development following decompressive surgery for lumbar spinal stenosis

BACKGROUND CONTEXT Decompressive surgery for symptomatic lumbar spinal stenosis is predictable and effective in providing relief of radiculopathy and neurogenic claudication. Decompression alone, without fusion, is generally reserved for patients with preserved lordosis and no evidence of instability. On occasion, spinal deformity and instability can occur following decompressive surgery and may lead to disabling symptoms and the need for revision surgery inclusive of an instrumented fusion. PURPOSE The purpose of this study was to evaluate the extent and nature of symptomatic deformity development occurring within one year following decompressive surgery for lumbar spinal stenosis. Multiple clinical and radiographic factors were assessed for their effect upon deformity development. Additionally, the ultimate clinical outcomes of patients who underwent revision surgery for deformity development were compared to a cohort of patients who had not developed a deformity after undergoing decompressive surgery during the same time period. STUDY DESIGN/SETTING Retrospective cohort study of prospectively collected data from a single institution. PATIENT SAMPLE A total of 425 patients underwent decompressive surgery over a 5-year period (2012-2016) for symptomatic lumbar spinal stenosis by one of four surgeons at a single spine center. All patients had preserved lordosis (no antero-, lateral, or retrolisthesis) on preoperative, upright radiographs and none had evidence of instability on flexion-extension films. All patients underwent open, multilevel laminectomies with lateral recess and foraminal decompression to address neural compression noted on preoperative MRI. OUTCOME MEASURES Pre- and postoperative VAS (back pain), VAS (leg pain), Oswestry Disability Index, and specific queries of patient satisfaction with surgery and willingness to repeat the index surgery. The indication for additional surgery early in the postoperative period ( METHODS Patients undergoing lumbar decompressive surgery were followed postoperatively at 6 weeks, 3 months, 6 months, and 1 year. If a patient developed a symptomatic deformity within the first year which required additional surgery, they were identified and compared to a cohort of patients who also underwent decompressive surgery over the same 5-year period but did not develop a postoperative deformity. RESULTS A total of 425 patients underwent a multilevel lumbar decompression for spinal stenosis over a 5-year period. Nineteen patients (4%) developed pain and radiographic evidence of a deformity within one year that necessitated an additional surgery in the form of an instrumented fusion. Back pain was present in all 19 patients and recurrent radicular pain was present in 16 of 19 patients (84%). Significant factors for development of a deformity included age 30 (p=.03), and fluid within multiple facet joints noted on preop MRI (p=.04). Notable factors that approached, but did not reach significance included patients with 4-level laminectomies (p=.05), osteoporosis (p=.05), and chronic, preoperative corticosteroid use (p=.05). Notable factors that were not significant included presence of congenital stenosis, type of preoperative employment (sedentary vs physically demanding), use of postoperative bracing, or duration of preoperative symptoms (greater or less than one year). When compared with a cohort of patients who did not develop a deformity, the deformity patients had poorer VAS (back) and ODI scores at 6 months following their revision surgery. By 1 year, and thereafter to 5 years postoperatively, the two cohorts had similar VAS (back and leg) and ODI scores and the percentage of patients in each cohort who had overall improvement in each outcome measure (VAS back, VAS leg, ODI) were similar in both cohorts. As well, there were no significant differences at 2-5 years postop in patient-reported satisfaction rates or willingness to repeat index surgery. CONCLUSIONS Deformity development within the first year following decompressive surgery for lumbar spinal stenosis was found to be an uncommon event, occurring in 4% of consecutive patients treated at a single spine center over a 5-year period. Younger, obese patients and those with greater than 3 levels decompressed were more likely to develop deformities, as were patients with fluid noted within multiple facet joints on preoperative MRI. However, long-term follow-up reveled no ultimate difference in outcomes of patients who required additional surgery for deformity development, including patient satisfaction and willingness to repeat the index lumbar decompressive procedure. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

The dimensions of "failed back surgery syndrome": what is behind a label?

The term failed back surgery syndrome (FBSS) has been criticized for being too unspecific and several studies have shown that a variety of conditions may underlie this label. The aims of the present study were to describe the specific symptoms and to investigate the primary and secondary underlying causes of FBSS in a contemporary series of patients who had lumbar spinal surgery before. We used a multilevel approach along three different axes defining symptomatic, morphological, and functional pathology dimensions. Within the study period of 3years, a total of 145 patients (74 f, 71 m, mean age 51a, range 32-82a) with the external diagnosis of FBSS were included. Disk surgery up to 4 times and surgery for spinal stenosis up to 3 times were the commonest index operations. Most often, the patients complained of low back pain (n = 126), pseudoradicular pain (n = 54), and neuropathic pain (n = 44). Imaging revealed osteochondrosis (n = 61), spondylarthrosis (n = 48), and spinal misalignment (n = 32) as the most frequent morphological changes. The majority of patients were assigned at least to two different symptomatic subcategories and morphological subcategories, respectively. According to these findings, one or more functional pathologies were assigned in 131/145 patients that subsequently enabled a specific treatment strategy. FBSS has become rather a vague and imprecisely used generic term. We suggest that it should be avoided in the future both with regard to its partially stigmatizing connotation and its inherent hindering to provide individualized medicine.

95. PROMIS scores alone are not a reliable measure of patient outcomes after surgery for lumbar stenosis

BACKGROUND CONTEXT As the health care industry shifts to a value-based care model, patient-reported outcome instruments such as the NIH-supported Patient-Reported Outcomes Measurement Information System (PROMIS), which evaluates patients’ global well-being, are increasingly used to gauge the cost-effectiveness of care. The Swiss Spinal Stenosis Questionnaire (SSSQ) is considered the gold standard validated disease-specific outcome measure for the treatment of lumbar spinal stenosis and has been found to be internally consistent, reproducible and responsive to clinical change. As PROMIS is further integrated into clinical care, its benefit must be evaluated relative to traditional PRO instruments such as the SSSQ. PURPOSE This study aims to establish the strength of relationship between three commonly used PROMIS measures and the SSSQ. STUDY DESIGN/SETTING Not applicable. PATIENT SAMPLE See methods section. OUTCOME MEASURES See methods section. METHODS Eighty-two patients with spinal stenosis at a single academic medical center were enrolled. They filled out one SSSQ during their enrollment visit. Patients completed the PROMIS Adult Depression (AD), Physical Function (PF), and Pain Interference (PI) instruments at each visit. For patients who had undergone lumbar decompressive surgery, PROMIS scores from the first two postop visits were averaged. Regression analysis was performed to evaluate the pain and physical function domains of the SSSQ against their respective PROMIS counterparts (PI and PF), treatment satisfaction component of the SSSQ against postop PROMIS scores, and combined pretreatment SSSQ against PROMIS AD. RESULTS PROMIS PF correlates moderately well with the SSSQ physical function domain (R2 0.14, p=0.0008) while PROMIS PI correlates poorly with the SSSQ pain domain (R2 0.03, p= 0.13). PROMIS AD correlates relatively poorly to the pretreatment SSSQ (R2 0.07, p= 0.02). In patients who have undergone surgery, postoperative PROMIS scores in all three domains correlate reasonably well with the treatment satisfaction component of the SSSQ [PROMIS AD (R2 0.13, p=0.01), PROMIS PI (R2 0.25, p= 0.003), PROMIS PF (R2 0.18, p= 0.003)]. CONCLUSIONS While postoperative PROMIS scores reflect patient outcomes after surgery for spinal stenosis reasonably well, preoperative PROMIS scores do not adequately capture the disease-specific impact of spinal stenosis on patients’ overall wellbeing. Therefore, PROMIS scores should not be used in isolation to assess outcomes in patients with spinal stenosis. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

269. Clinically relevant improvement is maintained 5 years after surgery for spinal stenosis

BACKGROUND CONTEXT Lumbar spinal stenosis (LSS) is a common condition in the elderly population and is associated with significant morbidity and decreased quality of life. Many patients manage with little to no treatment, but for the patients in whom lower extremity pain and disability are unacceptable, surgical intervention is shown to provide good relief of symptoms and pain. There is little evidence on how many patients obtain a clinically relevant improvement in function and whether this effect is sustained 5 years after surgery. PURPOSE The aim of this study was to evaluate the proportion of patients who achieve and maintain a clinically relevant improvement at 1, 2 and 5 years postoperatively. STUDY DESIGN/SETTING The study was performed as a retrospective cohort study on patients who underwent surgery at the Spine Centre of Southern Denmark, Middelfart; The Regional Hospital of Silkeborg and University Hospital of Zealand in Koge. PATIENT SAMPLE A total of 6,063 patients who underwent decompression due to spinal stenosis at three spine centers in Denmark were included in our study. We had follow-up data available on our main outcome measure (ODI) on 75% at 1-year, 70% at 2-year, and 62% at 5-year follow-up. OUTCOME MEASURES Oswestry Disability Index (ODI), EuroQoL-5D-3L (EQ-5D), visual analogue scale leg pain (VAS-leg) and visual analogue scale back pain (VAS-back). METHODS We included patients who underwent first-time decompression due to LSS at three tertiary Spine Centers in Denmark. Data was collected prospectively in the National Spine Registry of Denmark (DaneSpine). Based on the outcome measures, the patients who obtained a minimal clinically relevant difference in outcome (MCID) were identified at 1-, 2- and 5-years post-surgery. RESULTS The mean change from baseline to 5-years post-surgery was 0.2 on EQ-5D; -18.9 on ODI, -18.9 on VAS back and 29.8 on VAS. We found that 86% of patients obtained the MCID on at least one parameter, with 68.9% obtaining MCID on two or more outcome measures. VAS back was found with a statistically important difference in the percentage of patients who achieved MCID at 1- and 5-years postsurgery. For the remaining outcome measures no statistically important difference was found. CONCLUSIONS Decompression as treatment for LSS is a safe and reliable option with low complication rates. Most patients achieve a clinically relevant difference in outcome on one or more parameters, which is maintained 5 years after surgery. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

270. Patterns of opioid and other prescription medication use in lumbar surgery for spinal stenosis: a national claims database analysis

BACKGROUND CONTEXT Low back pain is one of the most common chronic pain conditions and pain medication use is common among lumbar spine surgery patients. Patients undergoing spine surgery have an increased risk for chronic opioid dependence, which is associated with poorer outcomes and increased surgical costs. However, details of specific patterns of opioid and non-opioid pain medication use pre- and postsurgery and how these might relate to chronic use are not well understood. PURPOSE 1) Characterize patterns in prescription medication use before and after surgery for lumbar spinal stenosis; 2) Identify phenotypes of patients that have similar patterns of medication utilization. STUDY DESIGN/SETTING Retrospective analysis of national claims data (Marketscan® 2007—2015). PATIENT SAMPLE Adult patients undergoing primary single level lumbar surgery for a diagnosis of stenosis (n=17,466, age 58.5±12.8 years, 49.9% female). Patients were required to have continuous enrollment in a health plan providing outpatient pharmacy data for at least 2 years before and after surgery to track medication usage and costs. OUTCOME MEASURES Percentage of patients using each class of pain medication pre- and postoperatively, median morphine milligram equivalents (MME), and medication costs (2015 US$). METHODS We conducted a retrospective analysis of national claims data (Marketscan® 2007—2015)Adult patients undergoing primary single level lumbar surgery for a diagnosis of stenosis (n=17,466, age 58.5±12.8 years, 49.9% female). Patients were required to have continuous enrollment in a health plan providing outpatient pharmacy data for at least 2 years before and after surgery to track medication usage and costs. RESULTS Median annual prescription costs were $1,810 (IQR: $410, $4,423) 2 years prior to surgery and $2,125 (IQR: $604, $4,908) in the year prior to surgery. Postoperatively, annual prescription costs were $2,021 (IQR: $553, $4,826) in the first year and $1,656 (IQR: $286, $4,697) in the second year. The percentage of patients taking opioids prior to surgery increased dramatically leading up to surgery and remained elevated 2 years postsurgery. To a lesser degree, the percentage of patients taking anxiolytics, muscle relaxants, and anticonvulsants also increased prior to surgery and remained elevated 2 years post-surgery. 84.3% of patients used opioids in the two years preoperatively, while 95.2% used opioids in the 2 years postoperatively. Of all prescriptions filed, the 3 most common opioid medications were hydrocodone bitartrate-acetaminophen (54.3%), oxycodone HCl-acetaminophen (15.6%), and oxycodone-HCl (5.5%). While the number of users increased dramatically leading up to surgery, in opioid users, the median dose of opioids taken remained relatively stable. However, the median MME taken per patient per month remained elevated 2 years after surgery (720 MME/month 2 years postop vs 492 MME 2 years preop). CONCLUSIONS The proportion of patients taking prescription drugs increased in the months leading up to spine surgery, and in many cases remained elevated 2 years postsurgery. In particular, the proportion of patients using opioids never dropped to levels observed 2 years preoperatively and opioid users were taking greater quantities of opioids 2 years postoperatively than they were 2 years preoperatively. Spine surgery has a lasting impact on medication use patterns. However, we hope that with greater attention paid to medication use, better progress can be made in the future to reverse these patterns. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Does “Coronal Root Angle” Serve as a Parameter in the Removal of Ventral Factors for Foraminal Stenosis at L5-S1 In Stand-alone Microendoscopic Decompression?

Prospective single-center cohort study. The present study aims to investigate the causes of failure of L5/S1 foraminal stenosis, and it is hypothesized that the newly defined "L5 coronal root angle (CRA)" may be a parameter in the removal of ventral pathologies. Lumbar foraminal stenosis is an important cause of recurrent leg pain after central spinal stenosis surgery. Although it can be seen at all levels, L5/S1 is the level at which it is most frequently seen due to its specific characteristics, with success rate is lower than other levels after foraminal decompression. L5/S1 microendoscopic foraminal decompression was performed to 51 patients. According to Japanese Orthopedic Association (JOA) improvement at 12-month follow-up, those with improvement >20% were classified as Group 1 and <20% were classified as Group 2. The patients who underwent discectomy in addition to foraminotomy formed Group 3. Lumbar lordosis angle, segmental lordosis angle, anterior disc height, pelvic tilt, pelvic incidence, sacral slope, relative disc height ratio, pedicle height/vertebral body height ratio, L5 depth, L5 CRA, and anterior disc height/ posterior disc height ratio parameters were measured with lumbar radiographic views, computed tomography (CT), and magnetic resonance imaging (MRI). Among the parameters compared between groups, L5 CRA, posterior disc height, anterior disc height/posterior disc height, relative disc height ratio, and lumbar lordosis angle during extension were seen to be statistically significantly related with low success rate. Failure to remove the ventral pathologies when the L5 CRA is <112. 1º may lead to failed results. Besides, in cases wherein the posterior disc height is <2.85 mm or the anterior/posterior disc height ratio is >3.98, approaches to restoring disc height rather than stand-alone posterior decompression may reduce the possibility of failure. 2.

The impact of multijoint symptoms on patient-reported disability following surgery for lumbar spine osteoarthritis

Background ContextIn the lumbar spine osteoarthritis (LS-OA) population having surgery for lumbar spinal stenosis (LSS) symptoms, a significant proportion of patients experience limited benefit following the intervention. Thus, identifying contributing factors to this is important. Individuals with OA often have multiple joint symptoms, yet this has received limited attention in this population. PurposeDocument the occurrence of joint symptoms among patients undergoing surgery for LS-OA, and investigate the influence of these symptoms on disability postsurgery. DesignProspective study of consecutive patients followed to 12-month postsurgery. Patient SamplePatients undergoing surgery (decompression surgery, with or without fusion) for neurogenic claudication with or without back pain due to LSS with a primary pathology diagnosis of LS-OA. Outcomes MeasuresPatient self-reported: Oswestry Disability Index (ODI), completed pre- and 12-month postsurgery; and, completed presurgery, age, sex, education, smoking, comorbid conditions, opioid use, short/long-term disability, depression and anxiety symptoms, back and leg pain intensity, presence of spondylolisthesis, procedure, prior spine surgery, and joints with arthritis and “pain/stiffness/swelling most days of the month” indicated on a homunculus (a joint site count was derived). Assessments: Height and weight, used to calculate body mass index; timed-up-and-go performance-based test. MethodsOutcome of interest was achieving a clinically important improvement (CII) in ODI by 12-month postsurgery (yes/no). The association between joint site count and achieving a CII was examined by multivariable logistic regression analyses, adjusted for other measures. ResultsIn all, 165 patients were included. The mean age was 67 years (range: 44–90) and 47% were female. Seventy-seven percent reported 1+ joint site other than the back, 62% reported 2+, and 25% reported 4+. Among those achieving a CII, 21% had 4+ joint sites, compared with 31% among those not achieving a CII. Adjusted analyses: Increasing joint site count was associated with increasing risk (odds ratio [OR]: 1.32, 95% confidence interval [CI]: 1.05, 1.66) of not achieving a CII; for those with 4+ joints, adjusted probability of not achieving a CII exceeded 50%. Also associated with an increased risk of not achieving a CII was presurgery anxiety (OR: 2.97, 95% CI: 1.02, 8.65), opioid use (OR: 2.89, 95% CI: 1.07, 7.82), and worse back pain intensity score (OR: 1.27, 95% CI: 1.05, 1.53). ConclusionsMultijoint involvement was highly prevalent in this LS-OA surgical sample. Its association with poorer postsurgery outcome supports a comprehensive approach to OA management and care. Knowledge of multijoint symptoms should inform patient education, shared decision-making, and recommendations for postsurgical rehabilitation and self-management strategies.

Preoperative epidural steroid injections are not associated with increased rates of infection and dural tear in lumbar spine surgery.

The study objectives were to use a large national claims data resource to examine rates of preoperative epidural steroid injections (ESI) in lumbar spine surgery and determine whether preoperative ESI or the timing of preoperative ESI is associated with rates of postoperative complications and reoperations. A retrospective longitudinal analysis of patients undergoing lumbar spine surgery for disc herniation and/or spinal stenosis was undertaken using the MarketScan® databases from 2007-2015. Propensity-score matched cohorts were constructed to compare rates of complications and reoperations in patients with and without preoperative ESI. Within the year prior to surgery, 120,898 (46.4%) patients had a lumber ESI. The median time between ESI and surgery was 10weeks. 23.1% of patients having preoperative ESI had more than one level injected, and 66.5% had more than one preoperative ESI treatment. Patients with chronic pain were considerably more likely to have an ESI prior to their surgery [OR 1.62 (1.54, 1.69), p < 0.001]. Patients having preoperative ESI within in close proximity to surgery did not have increased rates of infection, dural tear, neurological complications, or surgical complications; however, they did experience higher rates of reoperations and readmissions than those with no preoperative ESI (p < 0.001). Half of patients undergoing lumbar spine surgery for stenosis and/or herniation had a preoperative ESI. These were not associated with an increased risk for postoperative complications, even when the ESI was given in close proximity to surgery. Patients with preoperative ESI were more likely to have readmissions and reoperations following surgery.

Changes in racial and ethnic disparities in lumbar spinal surgery associated with the passage of the Affordable Care Act, 2006–2014

BACKGROUND CONTEXTSince implementation of the Patient Protection and Affordable Care Act (ACA) in 2010, more Americans have health insurance, and many racial/ethnic disparities in healthcare have improved. We previously reported that Black and Hispanic patients undergo surgery for spinal stenosis at lower rates than do white patients. PURPOSETo assess changes in racial/ethnic disparities in rates of lumbar spinal surgery after passage of the ACA. STUDY DESIGNRetrospective analysis. PATIENT SAMPLEApproximately 3.2 million adults who underwent lumbar spinal surgery in the US from 2006 through 2014. OUTCOME MEASURESRacial disparities in discharge rates before versus after ACA passage. METHODSUsing the Nationwide Inpatient Sample, the U.S. Census Bureau Current Population Survey Supplement, and International Classification of Diseases, Ninth Revision, Clinical Modification, criteria for definite lumbar spinal surgery, we calculated rates of lumbar spinal surgery as the number of hospital discharges divided by population estimates and stratified patients by race/ethnicity after controlling for sociodemographic characteristics. Calendar years were stratified as before ACA passage (2006–2010) or after ACA passage (2011–2014). Poisson regression was used to model hospital discharge rates as a function of race/ethnicity before and after ACA passage after adjustment for potential confounders. RESULTSAll rates are expressed per 1,000 persons. The overall median discharge rate decreased from 1.9 before ACA passage to 1.6 after ACA passage (p < .001). After adjustment for sociodemographic factors, the Black:White disparity in discharge rates decreased from 0.40:1 before ACA to 0.44:1 after ACA (p < .001). A similar decrease in the Hispanic:White disparity occurred, from 0.35:1 before ACA to 0.38:1 after ACA (p < .001). CONCLUSIONSmall but significant decreases occurred in racial/ethnic disparities in hospital discharge rates for lumbar spinal surgery after ACA passage.

Surgery for Lumbar Spinal Stenosis in Patients With Mild Leg Pain Levels Is Associated With Unsatisfactory Outcome.

Study Design:Prospective register cohort study.Objectives:The indication for surgery in patients with lumbar spinal stenosis (LSS) is considered to be leg pain and neurogenic claudication (NC). Nevertheless, a significant part of patients operated for LSS have mild leg pain levels defined as leg pain ≤minimally important clinical difference (MICD). Information is lacking on how to inform these patients about the probable outcome of surgery. The objective was to report the outcome of surgery for LSS in patients with a mild preoperative level of leg pain.Methods:A total of 2559 patients operated upon for LSS with preoperative leg pain ≤3 NRS (Numerical Rating Scale) were evaluated for outcome at the 1-year follow-up. NRS for back pain, the Oswestry Disability Index (ODI), and the EuroQol (EQ-5D) were used.Results:In the period 2007 to 2017, we identified 3239 patients (14%) who had mild leg pain (≤3 on the NRS). In this cohort, leg pain increased 0.40 (0.56-0.37) and back pain decreased 1.0 (0.95-1.2) at the 1-year follow up. ODI decreased 11.1 (10.2-11.4) and the EQ-5D increased 0.15 (0.17-0.14). A total of 31% reached successful outcome in terms of back pain, 43% in terms of ODI and 48% in terms of EQ-5D. 63% of the patients were satisfied with the outcome.Conclusion:A minority of patients with mild leg pain levels operated upon for LSS attain MICD for back pain, ODI, and EQ-5D. The results from this study can aid the surgeon in the shared decision-making process before surgery.

Canadian Spine SocietyPresentation CPSS1: Spinal insufficiency fracture in the geriatric pediatric spinePresentation CPSS2: The clinical significance of tether breakages in anterior vertebral body growth modulation: a 2-year postoperative analysisPresentation CPSS3: Anterior vertebral body growth modulation for idiopathic scoliosis: early, mid-term and late complicationsPresentation CPSS4: Ovine model of congenital chest wall and spine deformity with alterations of respiratory mechanics: follow-up from

Canadian Spine SocietyPresentation CPSS1: Spinal insufficiency fracture in the geriatric pediatric spinePresentation CPSS2: The clinical significance of tether breakages in anterior vertebral body growth modulation: a 2-year postoperative analysisPresentation CPSS3: Anterior vertebral body growth modulation for idiopathic scoliosis: early, mid-term and late complicationsPresentation CPSS4: Ovine model of congenital chest wall and spine deformity with alterations of respiratory mechanics: follow-up from

Building block osteotomy, a new back muscle-preserving laminoplasty for lumbar spinal stenosis

In order to preserve paravertebral muscles and posterior ligaments complex (PLC), this paper proposes a new lumbar laminoplasty surgery for lumbar spinal stenosis (LSS). According to the anatomy of back muscles insertions, building block osteotomy (BBO) which aimed to achieve precise osteotomy and reconstruction based on modular design theory was firstly put forward, and supposed to be achieved by an ultrasound bone scalpel (UBS). In details, lumbar spinous processes are longitudinally split, then supraspinous and interspinous ligaments are sharply cut off longitudinally. After converting to lumbar flexion, lamina osteotomy is innovatively finished by an UBS through interspinous space. After decompression, hollow screws are firstly suggested to be used on each side to fix lamina and spinous processes, and PLC is reconstructed by interrupted suture. Feasibility of this method is evaluated in details. Challenges, advantages and disadvantages are also discussed.