Publications by authors named "Kai-Uwe Lewandrowski"

70 Publications

Full-Endoscopic Oblique Lateral Lumbar Interbody Fusion: A Technical Note With 1-Year Follow-Up.

Int J Spine Surg 2021 Jun 7;15(3):504-513. Epub 2021 May 7.

Desert Institute for Spine Care, Phoenix, Arizona; Executive Director International Intradiscal Therapy Society, Phoenix, Arizona.

Background: Oblique lateral lumbar interbody fusion (OLLIF) is a minimally invasive lumbar interbody fusion procedure using a bullet-shaped polyetheretherketone (PEEK) nonexpandable fusion cage modified to diminish risk to the exiting nerve root during posterolateral implantation through the Kambin safe zone under fluoroscopic guidance. The objective of this study was to present feasibility of this procedure and 1-year clinical outcome data.

Methods: The authors present a prospective cohort study of 20 patients who underwent fluoroscopy-guided and full-endoscopic OLLIF in 22 segments allowing protection of the exiting nerve root from January 2018 to March 2019. The foraminoplasty, discectomy, endplate preparation, placement of bone graft and insertion of the fusion cage was done under continuous full-endoscopic visualization. The OLLIF fusion was backed up with bilateral percutaneous posterior supplemental pedicle screw fixation. Primary clinical outcome measures were the visual analog scale (VAS) of low back and leg pain, and Oswestry disability index (ODI) at 1 week, 3 months, 6 months, and 1 year after the operation. At final follow-up, the Macnab score was also evaluated. Secondary outcome measures were computed tomography (CT) assessment fusion using the Mannion classification of spinal fusion and adverse events related to the device as well as magnetic resonance imaging (MRI) assessment of nerve root decompression.

Results: All patients had significant relief of low back pain and leg pain, by VAS and ODI scores that improved significantly ( < .01). There were no complications. Postoperative lumbar MRI of all patients showed sufficient direct nerve decompression. At 1-year follow-up, excellent Macnab outcomes were obtained 13 patients, good in six, and fair in one. Impaired sensation and muscle strength of the involved nerve root significantly recovered in all but 2 patients ( < .05). According to the Mannion CT-based classification of spinal fusion, CT showed complete interbody fusion achieved in all 22 segments.

Conclusions: Full-endoscopic OLLIF is a safe, effective, minimally invasive, economical, practical, and widely applicable minimally invasive interbody fusion technique in the lumbar spine.

Level Of Evidence: 3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/8072DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8176836PMC
June 2021

Dural Tears During Lumbar Spinal Endoscopy: Surgeon Skill, Training, Incidence, Risk Factors, and Management.

Int J Spine Surg 2021 Apr 1;15(2):280-294. Epub 2021 Apr 1.

University of New Mexico School of Medicine, Albuquerque, New Mexico.

Background: Incidental dural tears during lumbar endoscopy can be challenging to manage. There is limited literature on their appropriate management, risk factors, and the clinical consequences of this typically uncommon complication.

Materials And Methods: To improve the statistical power of studying durotomy with lumbar endoscopy, we performed a retrospective survey study among endoscopic spine surgeons by email and chat groups on social media networks, including WhatsApp and WeChat. Descriptive and correlative statistics were done on the surgeons' recorded responses to multiple-choice questions. Surgeons were asked about their clinical experience with spinal endoscopy, training background, the types of lumbar endoscopic decompression they perform by approach, the decompression instruments they use, and incidental durotomy incidence with routine lumbar endoscopy.

Results: There were 689 dural tears in 64 470 lumbar endoscopies, resulting in an incidental durotomy incidence of 1.07%. Seventy percent of the durotomies were reported by 20.4% of the surgeons. Eliminating these 19 outlier surgeons yielded an adjusted durotomy rate of 0.32. Endoscopic stenosis decompression (54.8%; < .0001), rather than endoscopic discectomy (44.1%; 41/93), was significantly more associated with durotomy. Medium-sized dural tears (1-10 mm) were the most common (52.2%; 48/93). Small pinhole durotomies (less than 1 mm) were the second most common type (46.7%; 43/93). Rootlet herniations were seen by 46.2% (43/93) of responding surgeons. The posterior dural sac injury during the interlaminar approach (57%; 53/93) occurred more frequently than traversing nerve-root injuries (31.2%) or anterior dural sac (23.7%; 22/93). Exiting nerve-root injuries (10.8%;10/93) were less common. Over half of surgeons did not attempt any repair or closure (52.2%; 47/90). Forty percent (36/90) used sealants. Only 7.8% (7/90) of surgeons attempted an endoscopic repair or sutures (11.1%; 10/90). DuralSeal was the most commonly used brand of commercially available sealant used (42.7%; 35/82). However, other sealants such as Tisseal (15.9%; 13/82), Evicel (2.4%2/82), and additional no-brand sealants (38; 32/82) were also used. Nearly half of the patients (48.3%; 43/89) were treated with 24-48 hours of bed rest. The majority of participating surgeons (64%; 57/89) reported that the long-term outcome was unaffected. Only 18% of surgeons reported having seen the development of a postoperative cerebrospinal fluid (CSF)-fistula (18%;16/89). However, the absolute incidence of CSF fistula was only 0.025% (16/64 470). Severe radiculopathy with dysesthesia; sensory loss; and motor weakness in association with an incidental durotomy were reported by 12.4% (11/89), 3.4% (3/89), and 2.2% (2/89) of surgeons, respectively.

Conclusions: The incidence of dural tears with lumbar endoscopy is about 1%. The incidence of durotomy is higher with the use of power drills and the interlaminar approach. Stenosis decompression that typically requires the more aggressive use of these power instruments has a slightly higher incidence of dural tears than does endoscopic decompression for a herniated disc. Most dural tears are small and can be successfully managed with mechanical compression with Gelfoam and sealants. Two-thirds of patients with incidental dural tears had an entirely uneventful postoperative course. The remaining one-third of patients may develop a persistent CSF leak, radiculopathy with dysesthesia, sensory loss, or motor function loss. Patients should be educated preoperatively and reassured.

Level Of Evidence: 3.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/8038DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8059391PMC
April 2021

Full Endoscopic Lumbar Discectomy Versus Laminectomy for Cauda Equina Syndrome.

Int J Spine Surg 2021 Feb 12;15(1):105-112. Epub 2021 Feb 12.

Spine Division of Orthopaedic Department, PLA General Hospital, Beijing, China.

Background: Typically, open surgery is advocated for cauda equina patients. The goal of this study was to compare the clinical efficacy of full endoscopic lumbar discectomy and laminectomy in the treatment of cauda equina syndrome (CES) caused by lumbar disc herniation.

Methods: Forty-three patients with CES either underwent endoscopic or laminectomy surgery from May 2015 to April 2016, and data were collected and retrospectively analyzed. The patients were divided into 2 groups according to the surgical methods: the endoscopy group (with 21 patients, 14 males and 7 females, and an average age of 42.67 with a standard deviation of 9.70 years) and the laminectomy group (with 22 patients, 16 males and 6 females, and an average age of 44.55 with a standard deviation of 9.36 years). The modified Japanese Orthopaedic Association (JOA) "leg-trunk-bladder" score was used to assess the efficacy of the respective surgical methods.

Results: Analysis showed longer surgery time, more bleeding, and longer hospital stay in the laminectomy group than in the endoscopy group with statistical significance. The postoperative JOA scores improved in both groups when compared with those before the operation, and the differences were statistically significant. There were no significant differences in JOA scores between the 2 groups at preoperation and 6-month and 1-year follow-ups. There was 1 patient in each group whose CES symptoms worsened after endoscopy. However, immediate reoperation resulted in satisfactory outcomes.

Conclusions: CES clinical symptom resolution was equal with endoscopy and laminectomy both in short-term and midterm follow-up. However, endoscopic treatment was advantageous by reducing the amount of bleeding, duration of surgery, and hospitalization days when compared to laminectomy.

Level Of Evidence: 3.

Clinical Relevance: Feasibility study Endoscopic Decompression for Cauda Equina.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/8014DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7931698PMC
February 2021

Minimally invasive debridement and drainage using intraoperative CT-Guide in multilevel spondylodiscitis: a long-term follow-up study.

BMC Musculoskelet Disord 2021 Jan 29;22(1):120. Epub 2021 Jan 29.

Department of Orthopaedics, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China.

Background: Spondylodiscitis is an unusual infectious disease, which usually originates as a pathogenic infection of intervertebral discs and then spreads to neighboring vertebral bodies. The objective of this study is to evaluate percutaneous debridement and drainage using intraoperative CT-Guide in multilevel spondylodiscitis.

Methods: From January 2002 to May 2017, 23 patients with multilevel spondylodiscitis were treated with minimally invasive debridement and drainage procedures in our department. The clinical manifestations, evolution, and minimally invasive debridement and drainage treatment of this refractory vertebral infection were investigated.

Results: Of the enrolled patients, the operation time ranged from 30 minutes to 124 minutes every level with an average of 48 minutes. Intraoperative hemorrhage was minimal. The postoperative follow-up period ranged from 12 months to 6.5 years with an average of 3.7 years. There was no reactivation of infection in the treated vertebral segment during follow-up, but two patients with fungal spinal infection continued to progress by affecting adjacent segments prior to final resolution. According to the classification system of Macnab, one patient had a good outcome at the final follow-up, and the rest were excellent.

Conclusions: Minimally invasive percutaneous debridement and irrigation using intraoperative CT-Guide is an effective minimally invasive method for the treatment of multilevel spondylodiscitis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1186/s12891-021-03988-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7844889PMC
January 2021

Feasibility of Deep Learning Algorithms for Reporting in Routine Spine Magnetic Resonance Imaging.

Int J Spine Surg 2020 Dec;14(s3):S86-S97

Multus Medical, LLC, Phoenix, Arizona.

Background: Artificial intelligence is gaining traction in automated medical imaging analysis. Development of more accurate magnetic resonance imaging (MRI) predictors of successful clinical outcomes is necessary to better define indications for surgery, improve clinical outcomes with targeted minimally invasive and endoscopic procedures, and realize cost savings by avoiding more invasive spine care.

Objective: To demonstrate the ability for deep learning neural network models to identify features in MRI DICOM datasets that represent varying intensities or severities of common spinal pathologies and injuries and to demonstrate the feasibility of generating automated verbal MRI reports comparable to those produced by reading radiologists.

Methods: A 3-dimensional (3D) anatomical model of the lumbar spine was fitted to each of the patient's MRIs by a team of technicians. MRI T1, T2, sagittal, axial, and transverse reconstruction image series were used to train segmentation models by the intersection of the 3D model through these image sequences. Class definitions were extracted from the radiologist report for the central canal: (0) no disc bulge/protrusion/canal stenosis, (1) disc bulge without canal stenosis, (2) disc bulge resulting in canal stenosis, and (3) disc herniation/protrusion/extrusion resulting in canal stenosis. Both the left and right neural foramina were assessed with either (0) neural foraminal stenosis absent, or (1) neural foramina stenosis present. Reporting criteria for the pathologies at each disc level and, when available, the grading of severity were extracted, and a natural language processing model was used to generate a verbal and written report. These data were then used to train a set of very deep convolutional neural network models, optimizing for minimal binary cross-entropy for each classification.

Results: The initial prediction validation of the implemented deep learning algorithm was done on 20% of the dataset, which was not used for artificial intelligence training. Of the 17,800 total disc locations for which MRI images and radiology reports were available, 14,720 were used to train the model, and 3560 were used to validate against. The convergence of validation accuracy achieved with the deep learning algorithm for the foraminal stenosis detector was 81% (sensitivity = 72.4.4%, specificity = 83.1%) after 25 complete iterations through the entire training dataset (epoch). The accuracy was 86.2% (sensitivity = 91.1%, specificity = 82.5%) for the central stenosis detector and 85.2% (sensitivity = 81.8%, specificity = 87.4%) for the disc herniation detector.

Conclusions: Deep learning algorithms may be used for routine reporting in spine MRI. There was a minimal disparity among accuracy, sensitivity, and specificity, indicating that the data were not overfitted to the training set. We concluded that variability in the training data tends to reduce overfitting and overtraining as the deep neural network models learn to focus on the common pathologies. Future studies should demonstrate the accuracy of deep neural network models and the predictive value of favorable clinical outcomes with intervention and surgery.

Level Of Evidence: 3.

Clinical Relevance: Feasibility, clinical teaching, and evaluation study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7131DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735442PMC
December 2020

Editors' Introduction: Modern Technology Applications in Minimally Invasive Spine Surgery Techniques.

Int J Spine Surg 2020 Dec;14(s3):S3

Department of Neurosurgery & Rehabilitation Medicine, University of Miami Miller School of Medicine, Miami, Florida.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7120DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735468PMC
December 2020

Artificial Intelligence Comparison of the Radiologist Report With Endoscopic Predictors of Successful Transforaminal Decompression for Painful Conditions of the Lumber Spine: Application of Deep Learning Algorithm Interpretation of Routine Lumbar Magnetic Resonance Imaging Scan.

Int J Spine Surg 2020 Dec 18;14(s3):S75-S85. Epub 2020 Nov 18.

Multus Medical, LLC, Phoenix, Arizona.

Background: Identifying pain generators in multilevel lumbar degenerative disc disease is not trivial but is crucial for lasting symptom relief with the targeted endoscopic spinal decompression surgery. Artificial intelligence (AI) applications of deep learning neural networks to the analysis of routine lumbar MRI scans could help the primary care and endoscopic specialist physician to compare the radiologist's report with a review of endoscopic clinical outcomes.

Objective: To analyze and compare the probability of predicting successful outcome with lumbar spinal endoscopy by using the radiologist's MRI grading and interpretation of the radiologic image with a novel AI deep learning neural network (Multus Radbot™) as independent prognosticators.

Methods: The location and severity of foraminal stenosis were analyzed using comparative ordinal grading by the radiologist, and a contiguous grading by the AI network in patients suffering from lateral recess and foraminal stenosis due to lumbar herniated disc. The compressive pathology definitions were extracted from the radiologist lumbar MRI reports from 65 patients with a total of 383 levels for the central canal - (0) no disc bulge/protrusion/canal stenosis, (1) disc bulge without canal stenosis, (2) disc bulge resulting in canal stenosis, and (3) disc herniation/protrusion/extrusion resulting in canal stenosis. Both neural foramina were assessed with either - (0) neural foraminal stenosis absent, or (1) neural foramina are stenosis present. Reporting criteria for the pathologies at each disc level and, when available, the grading of severity were extracted and assigned into two categories: "Normal," and "Stenosis." Clinical outcomes were graded using dichotomized modified Macnab criteria considering and results as "Improved," and and outcomes as "Not Improved." Binary logistic regression analysis was used to predict the probability of the AI- and radiologist grading of stenosis at the 88 foraminal decompression sites to result in "Improved" outcomes.

Results: The average age of the 65 patients was 62.7 +/- 12.7 years. They consisted of 51 (54.3%) males and 43 (45.7%) females. At an average final follow-up of 57.4 +/- 12.57, Macnab outcome analysis showed that 86.4% of the 88 foraminal decompressions resulted in and (Improved) clinical outcomes. The stenosis grading by the radiologist showed an average severity score of 4.71 +/- 2.626, and the average AI severity grading was 5.65 +/- 3.73. Logit regression probability analysis of the two independent prognosticators showed that both the grading by the radiologist (86.2%; odds ratio 1.264) and the AI grading (86.4%; odds ratio 1.267) were nearly equally predictive of a successful outcome with the endoscopic decompression.

Conclusions: Deep learning algorithms are capable of identifying lumbar foraminal compression due to herniated disc. The treatment outcome was correlated to the decompression of the directly visualized corresponding pathology during the lumbar endoscopy. This research should be extended to other validated pain generators in the lumbar spine.

Level Of Evidence: 3.

Clinical Relevance: Validity, clinical teaching, evaluation study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7130DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735439PMC
December 2020

Endoscopic Transforaminal Lumbar Interbody Fusion With a Single Oblique PEEK Cage and Posterior Supplemental Fixation.

Int J Spine Surg 2020 Dec 29;14(s3):S45-S55. Epub 2020 Oct 29.

Center for Advanced Spine Care of Southern Arizona and Surgical Institute of Tucson, Tucson, Arizona, Department Neurosurgery, UNIRIO, Rio de Janeiro, Brazil, Department of Orthopaedics, Fundación Universitaria Sanitas, Bogotá, DC, Colombia.

Background: To demonstrate the feasibility of an endoscopically assisted minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF) and to study clinical outcomes with the use of a static oblique bullet-shaped cannulated poly-ether-ether-ketone (PEEK) lumbar interbody fusion cage in conjunction with platelet enriched plasma infused allograft cancellous chips and posterior supplemental fixation.

Methods: In this retrospective study of 43 patients who underwent endoscopically assisted MIS-TLIF for spondylolisthesis (53.5%) and stenosis (46.3%), the Oswestry Disability Index, the visual analog scale (VAS) for back and leg pain, and the modified Macnab criteria were used as primary clinical outcome measures. Clinical outcomes were cross-tabulated against fusion grade using the Bridwell classification of interbody fusion.

Results: The majority of patients (90.7%) had excellent (8/43; 18.6%) and good (31/43; 72.1%) Macnab outcomes. There were significant VAS back score reductions from an average preoperative values of 8.9070 to a postoperative VAS score of 3.8605, and a score of 2.7674 at final follow-up ( < .0001). The reductions in the VAS leg scores were also significant from preoperative score of 5.58 to a postoperative value of 2.16, and a final follow-up score of 1.67 ( < .0001); the Oswestry Disability Index score went from a preoperative value of 54.4 to 23.3 postoperatively and 18.5 at the final follow-up ( < .0001). The vast majority of patients (92.9%) with Bridwell grade I fusion had excellent and good Macnab outcomes ( = .027).

Conclusions: The authors recommend the use of an endoscope as an adjunct to MIS-TLIF, a minimally invasive spinal surgery technique in which many surgeons may be well versed and have a great deal of experience. Clinical outcomes with the endoscopic interbody fusion procedure with a static PEEK cage in conjunction with platelet-enriched bone allograft were favorable.

Level Of Evidence: 3.

Clinical Relevance: Feasibility study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7126DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735474PMC
December 2020

Expandable Interbody Fusion Cages: An Editorial on the Surgeon's Perspective on Recent Technological Advances and Their Biomechanical Implications.

Int J Spine Surg 2020 Dec 29;14(s3):S56-S62. Epub 2020 Oct 29.

Carnegie Mellon University, Neurosurgical and Spine Research, Allegheny General Hospital, Pittsburgh, Pennsylvania.

Background: Expandable cages have gone through several iterations since they first appeared on the market in the early 2000s. Their development was prompted by some common problems associated with static interbody cages, including migration, expulsion, dural or neural traction injury, and pseudarthrosis.

Objective: To summarize current technological advances from earlier expandable lumbar interbody fusion devices to implants with vertical and medial-to-lateral expansion mechanisms.

Methods: The authors review the currently available expandable cage designs, the incremental technological advances, and how these devices impact minimally invasive surgery interbody procedures and clinical outcomes. The strategic concepts intended to improve the minimally invasive application of expandable interbody fusion implants are reviewed from a surgeon's perspective in a clinical context to discuss how their use may improve patient outcomes.

Conclusions: The geometrical configuration, effective stiffness of composite multi-material cage designs may impact the bone-implant contact area with the endplates. Hybridization strategies of expandable cage technology with modern minimally invasive and endoscopic spinal surgery techniques are presented by outlining their advantages and disadvantages.

Level Of Evidence: 1 CLINICAL RELEVANCE: Systematic review.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7127DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735473PMC
December 2020

Transforaminal Endoscopic Discectomy Combined With an Interspinous Process Distraction System for Spinal Stenosis.

Int J Spine Surg 2020 Dec 29;14(s3):S4-S12. Epub 2020 Oct 29.

Centro de Columna-Cirugía Mínima Invasiva, Bogotá, Colombia.

Background: The combination of the percutaneous transforaminal endoscopic decompression (PTED) with an interspinous process distraction system (IPS) may offer additional benefit in the treatment of spinal stenosis in patients who have failed nonsurgical treatment.

Methods: We retrospectively reviewed the medical records of 33 patients diagnosed with lumbar stenosis and radiculopathy and treated them with transforaminal endoscopic lumbar decompression between 2013 and 2017. Primary outcome measures were modified Macnab as well as preoperative and postoperative visual analog scale (VAS) criteria and the Oswestry Disability Index (ODI). Only patients with a minimum follow-up of 2 years were included.

Results: A total of 28 patients were treated with a combination of PTED and percutaneous IPS (group A), and 5 patients were treated with PTED and mini-open IPS (group B). In group A patients, there was a 4.48 reduction in the VAS score. The ODI changed from 50.25 preoperatively to 18.2 postoperatively, and excellent and good Macnab outcomes were obtained in 78% of patients. In group B patients, the mean VAS reduction was 5.2 points. The ODI changed from 44.34 preoperatively to 14.62 postoperatively, and 80% of group B patients achieved excellent and good Macnab outcomes. No complications related to PTED or IPS were observed throughout the 2-year follow-up.

Conclusions: The addition of IPS to the PTED procedure in select patients may offer additional benefits to patients being treated for lumbar lateral stenosis and foraminal stenosis with low-grade spondylolisthesis.

Level Of Evidence: 3.

Clinical Relevance: Feasibility study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735475PMC
December 2020

Reliability Analysis of Deep Learning Algorithms for Reporting of Routine Lumbar MRI Scans.

Int J Spine Surg 2020 Dec 29;14(s3):S98-S107. Epub 2020 Oct 29.

Multus Medical, LLC, Phoenix, Arizona.

Background: Artificial intelligence could provide more accurate magnetic resonance imaging (MRI) predictors of successful clinical outcomes in targeted spine care.

Objective: To analyze the level of agreement between lumbar MRI reports created by a deep learning neural network (RadBot) and the radiologists' MRI reading.

Methods: The compressive pathology definitions were extracted from the radiologist lumbar MRI reports from 65 patients with a total of 383 levels for the central canal: (0) no disc bulge/protrusion/canal stenosis, (1) disc bulge without canal stenosis, (2) disc bulge resulting in canal stenosis, and (3) disc herniation/protrusion/extrusion resulting in canal stenosis. For both, neural foramina were assessed with either (0) neural foraminal stenosis absent or (1) neural foramina stenosis present. Reporting criteria for the pathologies at each disc level and, when available, the grading of severity were extracted, and the Natural Language Processing model was used to generate a verbal and written report. The RadBot report was analyzed similarly as the MRI report by the radiologist. MRI reports were investigated by dichotomizing the data into 2 categories: normal and stenosis. The quality of the RadBot test was assessed by determining its sensitivity, specificity, and positive and negative predictive value as well as its reliability with the calculation of the Cronbach alpha and Cohen kappa using the radiologist MRI report as a gold standard.

Results: The authors found a RadBot sensitivity of 73.3%, a specificity of 88.4%, a positive predictive value of 80.3%, and a negative predictive value of 83.7%. The reliability analysis revealed the Cronbach alpha as 0.772. The highest individual values of the Cronbach alpha were 0.629 and 0.681 when compared to the MRI report by the radiologist, rending values of 0.566 and 0.688, respectively. Analysis of interobserver reliability rendered an overall kappa for the RadBot of 0.627. Analysis of receiver operating characteristics (ROC) showed a value of 0.808 for the area under the ROC curve.

Conclusions: Deep learning algorithms, when used for routine reporting in lumbar spine MRI, showed excellent quality as a diagnostic test that can distinguish the presence of neural element compression (stenosis) at a statistically significant level ( < .0001) from a random event distribution. This research should be extended to validated and directly visualized pain generators to improve the accuracy and prognostic value of the routine lumbar MRI scan for favorable clinical outcomes with intervention and surgery.

Level Of Evidence: 3.

Clinical Relevance: Validity, clinical teaching, and evaluation study.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7132DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735462PMC
December 2020

Current Concepts of Contemporary Expandable Lumbar Interbody Fusion Cage Designs, Part 1: An Editorial on Their Biomechanical Characteristics.

Int J Spine Surg 2020 Dec 29;14(s3):S63-S67. Epub 2020 Oct 29.

Carolina Neurosurgery & Spine Associates, Charlotte, North Carolina.

Background: Bidirectional expandable designs for lumbar interbody fusion cages are the latest iteration of expandable spacers employed to address some of the common problems inherent to static interbody fusion cages.

Objective: To describe the rationales for contemporary bidirectional, multimaterial expandable lumbar interbody fusion cage designs to achieve in situ expansion for maximum anterior column support while decreasing insertion size during minimal-access surgeries.

Methods: The authors summarize the current concepts behind expandable spinal fusion open architecture cage designs focusing on advanced minimally invasive spinal surgery techniques, such as endoscopy. A cage capable of bidirectional expansion in both height and width to address constrained surgical access problems was of particular interest to the authors while they analyzed the relationship between implant material stiffness and geometric design regarding the risk of subsidence and reduced graft loading.

Conclusions: Biomechanical advantages of new bidirectional, multimaterial expandable interbody fusion cages allow insertion through minimal surgical access and combine the advantages of proven device configurations and advanced material selection. The final construct stiffness is sufficient to provide immediate anterior column support while accommodating reduced sizes required for minimally invasive surgery applications.

Level Of Evidence: 7.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7128DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7735463PMC
December 2020

Feasibility of Using Intraoperative Neuromonitoring in the Prophylaxis of Dysesthesia in Transforaminal Endoscopic Discectomies of the Lumbar Spine.

Brain Sci 2020 Aug 5;10(8). Epub 2020 Aug 5.

The Federal University of the State of Rio de Janeiro UNIRIO, Pain and Spine Minimally Invasive Surgery Service at Gaffrée Guinle University Hospital HUGG, Tijuca, Rio de Janeiro 20270-004 RJ, Brazil.

(1) Background: Postoperative nerve root injury with dysesthesia is the most frequent sequela following lumbar endoscopic transforaminal discectomy. At times, it may be accompanied by transient and rarely by permanent motor weakness. The authors hypothesized that direct compression of the exiting nerve root and its dorsal root ganglion (DRG) by manipulating the working cannula or endoscopic instruments may play a role. (2) Objective: To assess whether intraoperative neurophysiological monitoring can help prevent nerve root injury by identifying neurophysiological events during the initial placement of the endoscopic working cannula and the directly visualized video endoscopic procedure. (3) Methods: The authors performed a retrospective chart review of 65 (35 female and 30 male) patients who underwent transforaminal endoscopic decompression for failed non-operative treatment of lumbar disc herniation from 2012 to 2020. The patients' age ranged from 22 to 86 years, with an average of 51.75 years. Patients in the experimental group (32 patients) had intraoperative neurophysiological monitoring recordings using sensory evoked (SSEP), and transcranial motor evoked potentials (TCEP), those in the control group (32 patients) did not. The SSEP and TCMEP data were analyzed and correlated to the postoperative course, including dysesthesia and clinical outcomes using modified Macnab criteria, Oswestry disability index (ODI), visual analog scale (VAS) for leg and back pain. (4) Results: The surgical levels were L4/L5 in 44.6%, L5/S1 in 23.1%, and L3/L4 in 9.2%. Of the 65 patients, 56.9% (37/65) had surgery on the left, 36.9% (24/65) on the right, and the remaining 6.2% (4/65) underwent bilateral decompression. Postoperative dysesthesia occurred in 2 patients in the experimental and six patients in the control group. In the experimental neuromonitoring group, there was electrodiagnostic evidence of compression of the exiting nerve root's DRG in 24 (72.7%) of the 32 patients after initial transforaminal placement of the working cannula. A 5% or more decrease and a 50% or more decrease in amplitude of SSEPs and TCEPs recordings of the exiting nerve root were resolved by repositioning the working cannula or by pausing the root manipulation until recovery to baseline, which typically occurred within an average of 1.15 min. In 15 of the 24 patients with such latency and amplitude changes, a foraminoplasty was performed before advancing the endoscopic working cannula via the transforaminal approach into the neuroforamen to avoid an impeding nerve root injury and postoperative dysesthesia. (5) Conclusion: Neuromonitoring enabled the intraoperative diagnosis of DRG compression during the initial transforaminal placement of the endoscopic working cannula. Future studies with more statistical power will have to investigate whether employing neuromonitoring to avoid intraoperative compression of the exiting nerve root is predictive of lower postoperative dysesthesia rates in patients undergoing videoendoscopic transforaminal discectomy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/brainsci10080522DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7465602PMC
August 2020

Lumbar Endoscopic Bony and Soft Tissue Decompression With the Hybridized Inside-Out Approach: A Review And Technical Note.

Neurospine 2020 Jul 31;17(Suppl 1):S34-S43. Epub 2020 Jul 31.

Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, USA.

This study aimed to showcase the authors' preferred technique of a hybrid of modern "inside-out" and "outside-in" endoscopic decompression. A case series of 411 patients consisting of 192 females (46.7%) and 219 males (53.3%) with an average age of 54.84 ± 16.32 years and an average of 43.2 ± 26.53 months are presented. Patients underwent surgery for low-grade spondylolisthesis (13 of 411, 3.2%), herniated disc (135 of 411, 32.8%), foraminal spinal stenosis (101 of 411, 24.6%), or a combination of the latter 2 conditions (162 of 411, 39.4%). The preoperative Oswestry Disability Index (ODI) and visual analogue scale (VAS) for leg pain were 49.8 ± 17.65 and 7.9 ± 1.55, respectively. Postoperative ODI and VAS leg were 12.2 ± 9.34 and 2.41 ± 5 1.55 at final follow-up (p < 0.0001). MacNab outcomes were excellent in 134 (32.6%), good in 228 (55.5%), fair in 40 (9.7%), and poor in 9 patients (2.2%), respectively. There was end-stage degenerative vacuum disc disease in 304 of the 411 patients (74%) of which had 37.5% had excellent and 50% good MacNab outcomes. Patients without vacuum discs had excellent and good 18.7% and 71.0% of the time. Direct visualization of pain generators in the epidural- and intradiscal space is the authors' preferred transforaminal decompression technique and is supported by their reliable clinical outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14245/ns.2040160.080DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7410382PMC
July 2020

Dysethesia due to irritation of the dorsal root ganglion following lumbar transforaminal endoscopy: Analysis of frequency and contributing factors.

Clin Neurol Neurosurg 2020 10 13;197:106073. Epub 2020 Jul 13.

Clinical Professor of Endoscopic Surgery, University of New Mexico School of Medicine Department of Neurosurgery Albuquerque, NM, United States; Desert Institute for Spine Care, Phoenix, AZ, USA.

Background: New onset of acute dysethetic leg pain due to irritation of the dorsal root ganglion (DRG) following uneventful recovery from an expertly executed lumbar transforaminal endoscopic decompression is a common problem. Its incidence and relation to any risk factors that could be mitigated preoperatively are not well understood.

Methods: We performed a multicenter frequency analysis of DRG irritation dysesthesia in 451 patients who underwent lumbar transforaminal endoscopic decompression for herniated disc and foraminal stenosis. The 451 patients consisted of 250 men and 201 women with an average age of 55.77 ± 15.6 years. The average follow-up of 47.16 months. The primary clinical outcome measures were the modified Macnab criteria. Chi-square testing was employed to analyze statistically significant associations between increased dysesthesia rates, preoperative diagnosis, the surgical level(s), and surgeon technique.

Results: At final follow-up, Excellent (183/451; 40.6 %) and Good (195/451; 43.2 %) Macnab outcomes were observed in the majority of patients (378/451; 83.8 %). The majority of study patients (354; 78.5 %) had an entirely uneventful postoperative recovery without any DRG irritation, but 21.5 % of patients were treated for it in the immediate postoperative recovery period with supportive care measures including activity modification, transforaminal epidural steroid injections, non-steroidal anti-inflammatories, gabapentin, or pregabalin. There was no statistically significant difference in dysesthesia rates between lumbar levels from L1 to S1, or between single (DRG rate 21.8 %) or two-level (DRG rate 20.2 %) endoscopic decompression (p = 0.742). A statistically significantly higher incidence of postoperative dysesthesia was observed in patients who underwent decompression for foraminal stenosis (38/103; 27 %), and recurrent herniated disc (7/10; 41.2 %; p = 0.039). There were also statistically significant variations in dysesthesia rates between the seven participating clinical study sites ranging from 11.6%-33% (p = 0.002). Unrelenting postoperative dysesthetic leg pain due to DRG irritation was statistically associated with less favorable long-term clinical outcomes with DRG rates as high as 45 % in patients with a Fair and 61.3 % in patients with Poor Macnab outcomes (p < 0.0001).

Conclusions: Postoperative dysesthesia following transforaminal endoscopic decompression should be expected in one-fifth of patients. There was no predilection for any lumbar level. Foraminal stenosis and recurrent herniated disc surgery are risk factors for higher dysesthesia rates. There was a statistically significant variation of dysesthesia rates between participating centers suggesting that the surgeon skill level is of significance. Severe postoperative dysesthesia may be a predictor of Fair of Poor long-term Macnab outcomes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clineuro.2020.106073DOI Listing
October 2020

Transforaminal endoscopic decompression and uninstrumented allograft lumbar interbody fusion: A feasibility study in patients with end-stage vacuum degenerative disc disease.

Clin Neurol Neurosurg 2020 09 9;196:106002. Epub 2020 Jun 9.

Center For Advanced Spine Care of Southern Arizona, Surgical Institute of Tucson, United States. Electronic address:

Objective: The authors investigated the feasibility of a transforaminal endoscopic decompression and un-instrumented lumbar interbody fusion procedures with cancellous bone allograft in patients painful with end-stage degenerative vacuum disc disease.

Patients & Methods: Twenty-nine patients who underwent endoscopic transforaminal foraminal and lateral recess decompression and direct intraoperative endoscopic visualization of a painful, hollow collapsed, rigid intervertebral disc space were grafted with cancellous allograft chips. In addition to the radiographic assessment of fusion, patients were followed for a minimum of 2 years postoperatively, and clinical outcomes were evaluated with VAS, ODI, and modified MacNab criteria.

Results: At the final follow, mean VAS and ODI scores reduced from 7.34 ± 1.63 and 50.03 ± 10.64 preoperatively to 1.62 ± 1.741 and 6.69 ± 4.294 postoperatively (p < 0.0001). Excellent and Good clinical outcomes, according to Macnab criteria, were obtained in 34.5 % and 62.1 % of patients, respectively. Only one patient had minimal improvement from "Poor" preoperatively to "Fair" postoperatively. This female patient was treated for lumbar disc herniation L5/S1 and had an incomplete fusion at the final follow up. Computed tomography assessment of interbody fusion at the last follow-up showed successful fusion in 91.4 % of patients.

Conclusions: Un-instrumented interbody fusion by packing a hollow interspace with cancellous bone allograft chips can be considered as an adjunct to endoscopic foraminal and lateral recess decompression in select patients with validated painful, collapsed, and rigid motion segments. It can be safely done in an outpatient setting at a low burden to patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.clineuro.2020.106002DOI Listing
September 2020

Minimal Clinically Important Difference in Patient-Reported Outcome Measures with the Transforaminal Endoscopic Decompression for Lateral Recess and Foraminal Stenosis.

Int J Spine Surg 2020 Apr 30;14(2):254-266. Epub 2020 Apr 30.

University of New Mexico School of Medicine Department of Neurosurgery Albuquerque, New Mexico; Desert Institute for Spine Care, Phoenix, Arizona.

Background: Patient-reported outcome measures (PROMs) have become widely used to better measure patients' judgment of treatment benefits from surgical spine care. The concept of determining the minimal clinically important differences (MCIDs) of PROMs is aimed at assessing the benefits of lumbar spine care that are meaningful to the patient. The goal of this study was to validate the utility of MCIDs of the visual analog score (VAS) and Oswestry Disability Index (ODI) in patients with sciatica-type low back and leg pain due to lateral recess and foraminal stenosis who were treated with directly visualized transforaminal outpatient endoscopic decompression.

Methods: The retrospective study population consisted of 406 patients on whom PROMs were obtained preoperatively, and again postoperatively at final follow-up. Employing an anchor-based approach with a patient satisfaction index based on the modified Macnab criteria, a receiver operating characteristics (ROC) and area under the curve (AUC) analysis was performed using IBM SPSS 25.0 to define the optimal MCID in VAS and ODI with the transforaminal endoscopy using the top-left-corner criteria and the Youden index. Improvements in walking endurance were recorded as an additional parameter of patient functioning and correlated with PROMs to test for statistical significance.

Results: The patients' average age was 41.08 years, ranging from 30 to 84 years. The mean follow-up was 33.59 months, ranging from 24 to 85 months, with a standard deviation of 12.79. The MCIDs for VAS and ODI were 2.5 to 3.5 and 15 to 16.5, respectively. Patients were dichotomized as improved (377/406; 92.9%) if they reported excellent (224/406; 55.2%), good (112/406; 27.6%), and fair (41/406; 10.1%) Macnab outcomes. Patients were dichotomized as failed if they reported poor (29/406; 7.1%) Macnab outcomes. Preoperatively, only 32.5% (132/406) of patients had unlimited walking endurance compared to 77.6% (315/406) of patients postoperatively. The ROC and AUC analysis showed better accuracy with the single-integer VAS score (0.926) than with the 10-item ODI score (0.751).

Conclusions: Transforaminal outpatient endoscopic decompression for symptomatic foraminal and lateral recess stenosis is an effective surgical treatment to alleviate sciatica-type and back symptoms in 92.9% of patients. Of the PROMs analyzed, the VAS provided a more meaningful and accurate reflection of patients' interpretation of outcome with the transforaminal endoscopic spinal decompression procedure than ODI. Understanding which patient expectations drive these MCIDs may aid in replacing open surgeries for sciatica-type low back and leg pain currently preferred by traditional spine surgeons with a personalized early-staged transforaminal endoscopic hybrid decompressive/ablative procedures favored by the authors. These may prove more cost effective by focusing on significant pain generators validated with a diagnostic interventional workup instead of employing image-based indication criteria for surgery.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.14444/7034DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7188088PMC
April 2020

Indication and Contraindication of Endoscopic Transforaminal Lumbar Decompression.

World Neurosurg 2021 01 19;145:631-642. Epub 2020 Mar 19.

Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, New Mexico; Associate, Desert Institute for Spine Care, Phoenix, Arizona, USA.

Background: The indications and contraindications to the endoscopic transforaminal approach for lumbar spinal stenosis are not well defined.

Methods: We performed a Kaplan-Meier durability survival analysis of patients with the following types of spinal stenosis: type I, central canal; type II, lateral recess; type III, foraminal; and type IV, extraforaminal. The 304 patients comprised 140 men and 164 women, with an average age of 51.68 ± 15.78 years. The average follow-up was 45.3 years (range, 18-90 years). The primary clinical outcome measures were the Oswestry Disability Index, visual analog scale, and the modified Macnab criteria.

Results: Of 304 study patients, 70 had type I (23.0%) stenosis, 42 type II (13.7%), 151 type III (49.7%), and 41 type IV (13.5%). Excellent outcomes were obtained in 114 patients (37.5%), good in 152 (50.0%), fair in 33 (10.9%), and poor in 5 (1.6%). Kaplan-Meier durability analysis of the clinical treatment benefit with the endoscopic transforaminal decompression surgery showed statistically significance differences (P < 0.0001) on log-rank (Mantel-Cox) χ testing between the estimated median (50% percentile) survival times of type I (28 months), type II (53 months), type III (32 months), and type IV (66 months).

Conclusions: We recommend stratifying patients based on the underlying compressive disease and the skill level of the endoscopic spine surgeon to decide preoperatively whether more difficult central or complex foraminal stenotic lesions should be considered for alternative endoscopic approaches.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.wneu.2020.03.076DOI Listing
January 2021

Subsidence induced recurrent radiculopathy after staged two-level standalone endoscopic lumbar interbody fusion with a threaded cylindrical cage: a case report.

J Spine Surg 2020 Jan;6(Suppl 1):S286-S293

Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, USA.

We report a case of subsidence induced recurrence of unilateral L5 and S1 radiculopathy six months following a successful staged two-level endoscopic standalone lumbar interbody fusion using the VARILIF-L™ device. The patient was a 64-year-old female who first underwent outpatient endoscopic fusion L4/5 for failed non-operative care of Grade I spondylolisthesis. Within 11 months from the L4/5 index procedure, she developed symptomatic adjacent segment disease stemming from the L5/S1 level. A preoperative computed tomography before the planned L5/S1 endoscopic standalone VARILIF™ fusion 15 months following her L4/5 VARILIF™ procedure revealed fusion at the L4/5 level with minimal subsidence of the VARILIF-L™ implant, and advanced degeneration of the L5/S1 motion segment with lateral recess and foraminal stenosis, reduced posterior disc height, and vacuum disc. The patient underwent uneventful L5/S1 endoscopic standalone fusion using the VARILIF-L™ implant with successful clinical outcome and resolution of back and leg symptoms. Six months after the second endoscopic L5/S1 VARILIF™ procedure she developed recurrent L5 and S1 radiculopathy. Computed tomography showed significant implant subsidence and formation of a large soft tissue bulge on the approach side behind the interbody fusion cage. The subsidence induced subsidence and loss of posterior disc height and the associated recurrence of nerve root compression of the traversing S1 and exiting L5 nerve root. The recurrent radiculopathy was eventually treated with another transforaminal endoscopic decompression which included a more generous foraminoplasty with resection of the remaining superior articular process including a partial S1 pediculectomy and additional resection of the posterior annulus as well as scar and bony tissue that had formed within the axillary hidden zone of Macnab. We concluded that recurrent radiculopathy might occur after standalone lumbar transforaminal endoscopic interbody fusion with an expandable threaded cylindrical cage as a result of vertical and angular subsidence.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.09.25DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063320PMC
January 2020

Standalone lordotic endoscopic wedge lumbar interbody fusion (LEW-LIF™) with a threaded cylindrical peek cage: report of two cases.

J Spine Surg 2020 Jan;6(Suppl 1):S275-S284

Fundación Universitaria Sanitas, Bogotá, D.C., Colombia.

We report two cases of a standalone lordotic endoscopic wedge lumbar interbody fusion (LEW-LIF™) with a stress-neutral non-expandable cylindrical threaded polyether ether ketone (PEEK) interbody fusion implant. Patients underwent full-endoscopic transforaminal decompression and fusion for symptomatic lateral recess stenosis due to disc herniation, and hypertrophy of the facet joint complex and ligamentum flavum and no more than grade I spondylolisthesis. Lumbar interbody fusion with cages traditionally calls for posterior supplemental fixation with pedicle screws for added stability. A more simplified version of lumbar decompression and fusion without pedicle screws would allow treating patients suffering from stenosis and instability induced sciatica-type low back and leg pain in an outpatient ambulatory surgery center setting (ASC). This would realize a significant reduction in cost as well as the burden to the patient with decreased postoperative pain and earlier return to function. A 62-year-old female patient had surgery at L4/5 for a 6-year history of worsening right sided sciatica-type leg- and low back pain. Another 79-year-old female had the same surgical management at L4/5 for a 5-year history of unrelenting left-sided spondylolisthesis-related symptoms. Both patients had an uneventful postoperative course until the last available follow-up of 24 weeks with greater than 60% VAS and Oswestry disability index (ODI) reductions. There was no evidence of implant expulsion, subsidence, or postoperative instability. We concluded that standalone outpatient lumbar transforaminal endoscopic interbody fusion with a non-expandable threaded cylindrical cage is feasible, and favorable clinical outcomes provide proof of concept to study long-term clinical outcomes in larger groups of patients.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.06.09DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063321PMC
January 2020

Regional variations in acceptance, and utilization of minimally invasive spinal surgery techniques among spine surgeons: results of a global survey.

J Spine Surg 2020 Jan;6(Suppl 1):S260-S274

University of New Mexico School of Medicine, Albuquerque, New Mexico, USA.

Background: Regional differences in acceptance and utilization of MISST by spine surgeons may have an impact on clinical decision-making and the surgical treatment of common degenerative conditions of the lumbar spine. The purpose of this study was to analyze the acceptance and utilization of various minimally invasive spinal surgery techniques (MISST) by spinal surgeons the world over.

Methods: The authors solicited responses to an online survey sent to spine surgeons by email, and chat groups in social media networks including Facebook, WeChat, WhatsApp, and Linkedin. Surgeons were asked the following questions: (I) Do you think minimally invasive spinal surgery is considered mainstream in your area and practice setting? (II) Do you perform minimally invasive spinal surgery? (III) What type of MIS spinal surgery do you perform? (IV) If you are performing endoscopic spinal decompression surgeries, which approach do you prefer? The responses were cross-tabulated by surgeons' demographic data, and their practice area using the following five global regions: Africa & Middle East, Asia, Europe, North America, and South America. Pearson Chi-Square measures, Kappa statistics, and linear regression analysis of agreement or disagreement were performed by analyzing the distribution of variances using statistical package SPSS Version 25.0.

Results: A total of 586 surgeons accessed the survey. Analyzing the responses of 292 submitted surveys regional differences in opinion amongst spine surgeons showed that the highest percentage of surgeons in Asia (72.8%) and South America (70.2%) thought that MISST was accepted into mainstream spinal surgery in their practice area (P=0.04) versus North America (62.8%), Europe (52.8%), and Africa & Middle East region (50%). The percentage of spine surgeons employing MISST was much higher per region than the rate of surgeons who thought it was mainstream: Asia (96.7%), Europe (88.9%), South America (88.9%), and Africa & Middle East (87.5%). Surgeons in North America reported the lowest rate of MISST implementation globally (P<0.000). Spinal endoscopy (59.9%) is currently the most commonly employed MISST globally followed by mini-open approaches (55.1%), and tubular retractor systems (41.8%). The most preferred endoscopic approach to the spine is the transforaminal technique (56.2%) followed by interlaminar (41.8%), full endoscopic (35.3%), and over the top MISST (13.7%).

Conclusions: The rate of implementation of MISST into day-to-day clinical practice reported by spine surgeons was universally higher than the perceived acceptance rates of MISST into the mainstream by their peers in their practice area. The survey suggests that endoscopic spinal surgery is now the most commonly performed MISST.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.09.31DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063310PMC
January 2020

Surgeon motivation, and obstacles to the implementation of minimally invasive spinal surgery techniques.

J Spine Surg 2020 Jan;6(Suppl 1):S249-S259

University of New Mexico School of Medicine, Albuquerque, New Mexico.

Background: This study aimed to analyze the motivators and obstacles to the implementation of minimally invasive spinal surgery techniques (MISST) by spinal surgeons. Motivators and detractors may impact the availability of MISST to patients and drive spine surgeons' clinical decision-making in the treatment of common degenerative conditions of the lumbar spine.

Methods: The authors solicited responses to an online survey sent to spine surgeons by email, and chat groups in social media networks including Facebook, WeChat, WhatsApp, and Linkedin. Descriptive statistics were employed to count the responses and compared to the surgeon's training. Kappa statistics and linear regression analysis of agreement were performed.

Results: A total of 430 surgeons accessed the survey. The completion rate was 67.4%. A total of 292 surveys were submitted by 99 neurosurgeons (33.9%), 170 orthopaedic surgeons (58.2%), and 23 surgeons of other postgraduate training (7.9%). Personal interest (82.5%) and patient demand (48.6%) were the primary motivators for MISST implementation. High equipment (48.3%) and disposables (29.1%) cost were relevant obstacles to MISST implementation. Local workshops (47.6%) and meetings in small groups (31.8%) were listed as the primary knowledge sources. Only 12% of surgeons were fellowship trained, but 46.3% of surgeons employed MISST in over 25% of their cases.

Conclusions: The rate of implementation of MISST reported by spine surgeons was found to be high but impeded by the high cost of equipment and disposables. The primary motivators for spine surgeons' desire to implement were personal interest and patient demand.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.08.02DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063314PMC
January 2020

Surgeon training and clinical implementation of spinal endoscopy in routine practice: results of a global survey.

J Spine Surg 2020 Jan;6(Suppl 1):S237-S248

University of New Mexico School of Medicine, Albuquerque, NM, USA.

Background: Training of spine surgeons may impact the availability of contemporary minimally invasive spinal surgery (MIS) to patients and drive spine surgeons' clinical decision-making when applying minimally invasive spinal surgery techniques (MISST) to the treatment of common degenerative conditions of the lumbar spine. Training requirements and implementation of privileges vary in different parts of the world. The purpose of this study was to analyze the training in relation to practice patterns of surgeons who perform lumbar endoscopic spinal surgery the world over.

Methods: The authors solicited responses to an online survey sent to spine surgeons by email, and chat groups in social media networks including Facebook, WeChat, WhatsApp, and Linkedin. Surgeons were asked the following questions: (I) please indicate your training? (II) What type of MISST spinal surgery do you perform? (III) How would you rate your experience in MIS lumbar spinal surgery and what percentage of your practice is MISST? And (IV) which avenue did you use to train for the MISST you currently employ in your clinical practice today? Descriptive statistics were applied to count responses and cross-tabulated them to the surgeon's training. Pearson Chi-square measures, kappa statistics, and linear regression analysis of agreement or disagreement were performed by analyzing the distribution of variances using statistical package SPSS version 25.0.

Results: A total of 430 surgeons accessed the survey. The completion rate was 67.4%. Analyzing the responses of 292 surveys submitted by 97 neurosurgeons (33.2%), 161 orthopaedic surgeons (55.1%), and 34 surgeons of other postgraduate training (11.6%) showed that only 14% (41/292) of surgeons had completed a fellowship. Surgeons rated their skill level 33.5% of the time as master and experienced surgeon, and 35.6% of the time as novice or surgeon with some experience. There were more master (64.6% versus 29.2%) and experienced (52% versus 40%) surgeons amongst orthopaedic surgeons than amongst neurosurgeons at a statistically significant level (P=0.11). There were near twice as many orthopaedic surgeons (54.3%) using endoscopic procedures in the lumbar spine as their favorite MISST than neurosurgeons (35.4%; P=0.096). Endoscopic spine surgeons' main sources of knowledge acquisition were (I) learning in small meetings (57.3%), (II) attending workshops (63.1%), and (III) national and international conferences (59.8%).

Conclusions: The majority of spine surgeons reported more than half of their cases employing MISST at a high skill level. Very few MISST surgeons are fellowship trained but attend workshops and various meetings suggesting that many of them are self-thought. Orthopaedic surgeons were more likely to implement endoscopic spinal surgery into the routine clinical practice. As endoscopic spine surgery gains more traction and patient demand, minimal adequate training will be part of the ongoing debate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.09.32DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063303PMC
January 2020

Is Asia truly a hotspot of contemporary minimally invasive and endoscopic spinal surgery?

J Spine Surg 2020 Jan;6(Suppl 1):S224-S236

Center for Advanced Spine Care of Southern Arizona and Surgical Institute of Tucson, Tucson, AZ, USA.

Background: The purpose of this study was to analyze the training in relation to practice patterns of surgeons in Asia who perform lumbar endoscopic spinal surgery in comparison to surgeons the world over. The authors solicited responses to an online survey sent to spine surgeons.

Methods: Pearson Chi-Square measures, Kappa statistics, and linear regression analysis of agreement or disagreement were performed by analyzing the distribution of variances of responses in relation to surgeons' training using statistical package SPSS Version 25.0.

Results: A total of 430 surgeons accessed the survey. The completion rate was 67.4%. Analyzing the responses of 292 surveys submitted by 97 neurosurgeons (33.2%), 161 orthopaedic surgeons (55.1%), and 34 surgeons of other postgraduate training (11.6%) showed that only 14.0% (41/292) of surgeons had completed a fellowship. Ninety-one of the 292 respondents were from Asian countries/regions. A statistically significantly higher percentage of Asian surgeons (96.7%) compared to non-Asian surgeons (81.6%) indicated that they perform modern minimally invasive (MIS) and endoscopic spinal (ES) surgery (P=0.001). Spinal endoscopy was employed by 70.3% of Asian versus 55.2% of non-Asian surgeons (P=0.015). Endoscopic decompression techniques requiring advanced training was employed nearly twice as high by the Asian surgeons than by non-Asian.

Conclusions: Training requirements for MIS and ES surgery and implementation of privileges vary in different parts of the world. While industry-sponsored weekend cadaver workshops have remained the mainstay of training aspiring endoscopic spinal surgeons in North America and Europe leaving many of them to become autodidacts.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.12.13DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063297PMC
January 2020

Virtual reality in spinal endoscopy: a paradigm shift in education to support spine surgeons.

J Spine Surg 2020 Jan;6(Suppl 1):S208-S223

Department of Orthopaedics, University of British Columbia, Vancouver, BC, Canada.

Background: Minimally invasive spine surgery (MISS) and endoscopic spine surgery have continually evolving indications in the cervical, thoracic, and lumbar spine. Endoscopic spine surgery entails treatment of disc disease, stenosis, spondylolisthesis, radiculopathy, and deformity. MISS involves complex motor skills in regions of variable anatomy. Simulator use has been proposed to aid in training and skill retention, preoperative planning, and intraoperative use.

Methods: A systematic review of five databases was performed for publications pertaining to the use of virtual (VR), augmented (AR), and mixed (MR) reality in MISS and spinal endoscopic surgery. Qualitative data analysis was undertaken with focus of study design, quality, and reported outcomes. Study quality was assessed using the Medical Education Research Quality Instrument (MERSQI) score and level of evidence (LoE) by a modified Oxford Centre for Evidence-Based Medicine (OCEBM) level for simulation in medicine.

Results: Thirty-eight studies were retained for data collection. Studies were of intervention-control, clinical application, and pilot or cross-sectional design. Identified articles illustrated use of VR, AR, and MR in all study designs. Procedures included pedicle cannulation and screw insertion, vertebroplasty, kyphoplasty, percutaneous transforaminal endoscopic discectomy (PTED), lumbar puncture and facet injection, transvertebral anterior cervical foraminotomy (TVACF) and posterior cervical laminoforaminotomy. Overall MERSQI score was low-to-medium [M =9.71 (SD =2.60); range, 4.5-13.5], and LoE was predominantly low given the number of purely descriptive articles, or low-quality randomized studies.

Conclusions: The current scope of VR, AR, and MR surgical simulators in MISS and spinal endoscopic surgery was described. Studies demonstrate improvement in technical skill and patient outcomes in short term follow-up. Despite this, overall study quality and levels of evidence remain low. Cohesive study design and reporting with focus on transfer validity in training scenarios, and patient derived outcome measures in clinical studies are required to further advance the field.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.11.16DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063305PMC
January 2020

Navigating the learning curve of spinal endoscopy as an established traditionally trained spine surgeon.

J Spine Surg 2020 Jan;6(Suppl 1):S197-S207

Department of Neurosurgery, University of New Mexico School of Medicine, Albuquerque, NM, USA.

Background: Traditionally trained spine surgeons may want to transition from open spinal surgeries to endoscopic decompressions. The aspiring endoscopic spine surgeon may have to overcome multiple hurdles to master a learning curve without readily available training. Replacing traditional time-proven open spinal surgeries with endoscopic decompression may put the surgeons' reputation at risk and have an additional negative impact on his or her practice due to reduced revenue. The authors report on the utility of the mentor- and proctorship concepts to facilitate the transition from traditional open to endoscopic outpatient spine surgeries.

Methods: The study population (learning curve groups) was provided by two traditionally trained "apprentice" surgeons who have been in practice for 12 and 28 years, respectively. They trained with the remaining two authors under mentorship and proctorship arrangements. A VAS and Macnab outcomes analysis was performed by one surgeon laminectomy versus endoscopy in relationship to the case log representative of the initial learning curve. The second surgeon performed a postoperative narcotic utilization analysis as a representative way of favorable clinical outcomes in relation to his increasing case log with spinal endoscopy.

Results: The learning curve study by the first author (NA Ransom-under the proctorship program) consisted of 40 patients with 20 patients each divided into the traditional laminectomy control group and 20 patients in the endoscopic group. There were 22 females and 18 males with an average age of 57.38 years and a mean follow-up of 38.58 months. The preoperative VAS for patients in both groups was 7.95 compared to the postoperative VAS at final follow-up of 4.01 with a statistically significant postoperative VAS reduction (P<0.001) but without any significant difference between open laminectomy control- and endoscopic decompression groups. The endoscopic learning curve group outcomes improved significantly after 15 cases (P<0.048). The second author (S Gollogly-under mentorship program) performed a similar review of his surgical cases log and noted a significant reduction of postoperative narcotic utilization as a result of improved outcomes after an initial learning curve of 15 cases. Clinical outcomes for both authors showed improved Macnab outcomes in the majority of patients (NA Ransom =65%; S Gollogly =57%) with a slightly higher success rate in the laminectomy group (70%) versus the endoscopy group (65%) at a statistical significant level (P=0.036).

Conclusions: The mentorship and proctorship approach is useful in helping traditionally trained spine surgeons to integrate spinal endoscopy into their well-established spine practices. Under the close guidance of an endoscopic master spine surgeon, the endoscopic learning curve may be comprehended by the experienced traditionally trained spine surgeon in approximately 15 lumbar decompression cases. During this initial 15-case learning curve, clinical outcomes with endoscopy may be slightly inferior to open laminectomy but may ultimately improve to equivalent levels.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.10.03DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063306PMC
January 2020

Comparative study of curative effect of spinal endoscopic surgery and anterior cervical decompression for cervical spondylotic myelopathy.

J Spine Surg 2020 Jan;6(Suppl 1):S186-S196

Center for Advanced Spine Care of Southern Arizona and Surgical Institute of Tucson, Tucson, AZ, USA.

Background: The aim of this study was to compare the clinical efficacy of endoscopic cervical spinal surgery with anterior cervical decompression and fusion (ACDF) in the treatment of cervical spondylotic myelopathy (CSM).

Methods: A total of forty-six CSM patients who were admitted to the Medical School of Chinese PLA and treated with endoscopic spine surgery or ACDF from January 2015 to June 2017 were collected. The patients were divided into the spinal endoscopy group and the ACDF group, according to the operation methods. The operation time, intraoperative blood loss and hospitalization stay of the two groups were recorded and compared. Japanese Orthopaedic Association (JOA) score before operation, three months, and one year after operation were recorded for intra-group and inter-group comparison. The improvement rates of JOA were compared between the two groups to evaluate the clinical efficacy.

Results: There were twenty-two cases in the spinal endoscopy group and twenty-four cases in the ACDF group. The mean operation lasting time, intraoperative blood loss and hospitalization stay in the spinal endoscopy group were significantly lower than those in the ACDF group (P<0.05). The postoperative JOA score of the two groups were significantly higher than those before the operation (P<0.05). There were no significant differences in the JOA score before operation, three months and one year after operation between the two groups (P>0.05). The improvement rates in the spinal endoscopy group were not significantly different compared to those in the ACDF group (P>0.05). There was no significant difference in the excellent rate (81.8% 83.3%) between the spinal endoscopy group and the ACDF group (P>0.05).

Conclusions: The short-term efficacy of spinal endoscopic surgery and ACDF was equal in the treatment of CSM. The spinal endoscopic surgery was significantly superior to ACDF in reducing the operation time, the intraoperative blood loss and the hospitalization stay.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.11.15DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063312PMC
January 2020

Surgical treatment of cervical radiculopathy using an anterior cervical endoscopic decompression.

J Spine Surg 2020 Jan;6(Suppl 1):S179-S185

Fundación Universitaria Sanitas, Bogotá, D.C., Colombia.

Background: Anterior endoscopic cervical decompression with discectomy and foraminotomy is an alternative to open surgical treatment of unrelenting cervical radiculopathy (CR) in patients who have failed non-operative treatment. The purpose of the study is to present the clinical outcomes of patient with CR treated with an anterior endoscopic approach.

Methods: We reviewed the medical records of 293 patients diagnosed with CR and treated with an anterior endoscopic cervical decompression between 1997 and 2018. Primary outcome measures were modified Macnab as well as pre- and postoperative visual analog scale (VAS) criteria.

Results: The average surgical time was 65 minutes. At 12 months follow-up, Excellent and Good Macnab outcomes were achieved in 90.1% of patients. The average VAS score reduction was 5.6. Complications occurred in 8 patients and were treated with a second procedure in 10 patients.

Conclusions: The anterior endoscopic cervical decompression is an attractive alternative to open anterior cervical discectomy and fusion (ACDF) with a low complication and reoperations rate.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.09.24DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063308PMC
January 2020

Lumbar vacuum disc, vertical instability, standalone endoscopic interbody fusion, and other treatments: an opinion based survey among minimally invasive spinal surgeons.

J Spine Surg 2020 Jan;6(Suppl 1):S165-S178

University of New Mexico School of Medicine, Albuquerque, NM, USA.

Background: A diseased lumbar intervertebral vacuum disc void of any structurally intact tissue may be vertically unstable. A primary standalone endoscopic decompression and interbody fusion surgery in the treatment of vertical instability in patients with a vacuum disc may be a more reliable treatment than decompression alone.

Methods: The authors solicited responses to an online survey sent to spine surgeons by email, and chat groups on social media networks, including Facebook, WeChat, WhatsApp, and Linkedin. Descriptive and correlative statistics were employed to count the responses and compare the surgeon's responses recorded on a Likert scale from 1 (disagree) to 10 (agree) or in multiple-choice questions. Surgeons were asked about their familiarity with the concept of vacuum disc and vertical instability and how they would treat such patients. Kappa statistics and linear regression analysis of agreement of incoming responses were performed.

Results: A total of 1,165 surgeons accessed the survey. The completion rate was 22.78. The majority surgeons were very familiar with the concept of a "vacuum disc" as a sign of end-stage lumbar degenerative disc disease and a collapsing lumbar motion segment (182/273; 66.7%; Likert score 6.53). The majority of surgeons also thought that vertical instability precedes anterolateral lumbar instability (187/273; 68.5%; Likert score 6.64) and that a vacuum disc may cause vertical instability with symptomatic dynamic foraminal & lateral recess stenosis (222/273; 81%; Likert score 7.48), mechanical back pain (201/273; 73.1%; Likert score 7.48), and may cause sciatica-type low back and leg pain (179/273; 66.3%; Likert score 6.59). The majority of surgeons indicated that vacuum phenomenon on radiographic studies is associated with vertical instability and collapse resulting in dynamic foraminal and lateral recess stenosis and should be treated surgically (199/266; 73.7%; 7 missing responses; Likert score 6.86). Preferred treatments were decompression alone without fusion (P<0.014). There was consensus in support of fusion by TLIF or PLIF with a Likert score of 6.68 (184/266; 69.2%; 7 missing responses). There was no consensus on standalone fusion.

Conclusions: Vacuum phenomenon on radiographic studies is associated with a vertical instability and collapse, resulting in dynamic foraminal and lateral recess stenosis that should be treated surgically. Preferred surgical treatments were decompression alone, decompression with interbody fusion using just bone graft, and fusion employing TLIF or PLIF. Further research into the clinical significance of lumbar vacuum disc, vertical instability and its most appropriate surgical treatments if any is necessary.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.11.02DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063324PMC
January 2020

Clinical outcomes with endoscopic resection of lumbar extradural cysts.

J Spine Surg 2020 Jan;6(Suppl 1):S133-S144

Center for Advanced Spine Care of Southern Arizona and Surgical Institute of Tucson, Tucson, USA.

Background: Lumbar extradural cysts may be associated with sciatica-type back and leg pain. The symptoms of clinical pain syndrome from synovial cysts are sometimes difficult to differentiate from those of lumbar disc herniation or spinal canal stenosis and may be identified to be a pain source when visualized endoscopically. The authors analyzed the clinical outcomes with their endoscopic resection to better establish clinical indications and prognosticators of favorable results.

Methods: Two-year Macnab outcomes, VAS scores, and complications were analyzed in a series of 48 patients treated with the endoscopic removal of extradural cyst encountered during routine transforaminal and interlaminar decompression for foraminal and lateral recess stenosis causing lumbar radiculopathy.

Results: There were 26 female and 22 male patients. The extradural cysts were most commonly encountered at L4/5 level in 26 patients (72.2%) followed by the L5/S1 level in 8 patients (22.2%), and in 2 patients (5.6%) at the L3/4 level, respectively. One patient underwent T9/10 decompression. At minimum 2-year follow-up, all patients were improved. Excellent results according to the Macnab criteria were obtained in 19/48 (39.6%) patients, good in 18/48 (37.5%), and fair in 11/48 (22.9%), respectively. The average preoperative VAS score for leg pain was 8.06±1.57 and reduced at a statistically significant level (P<0.000) postoperatively to 1.92±1.49, and 1.77±1.32 at final follow-up, respectively. The percentage of patients with unlimited walking endurance had improved at a statistically significant level (P<0.0001) from 33.3% preoperatively (16/48) to 81.3% (39/48) postoperatively. One patient had a recurrent disc herniation, and another patient did not improve. Two patients underwent fusion during the follow-up period. Patients with Fair outcomes had a statistically significant association (P<0.001) with facet instability as suggested by axial T2-weighted magnetic resonance imaging (MRI) findings of thickened ligamentum flavum, facet joint hypertrophy, and bright white fluid-filled joint gap of >2 mm.

Conclusions: Endoscopic resection of extradural spinal cysts during routine decompression for symptomatic foraminal and lateral recess stenosis is feasible with favorable clinical outcomes in the majority of patients. Fair outcomes were associated with advanced instability of the involved lumbar facet joint complex.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.21037/jss.2019.08.08DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7063300PMC
January 2020