Surgical Intervention for Primary B-cell Lymphoma of the Spine: A Systematic Review and Meta-analysis of Clinical Presentation, Treatment, Postoperative Outcomes, and Histologic Markers.

STUDY DESIGN: Systematic review and meta-analysis. OBJECTIVE: To perform a systematic review of the clinical symptoms, radiographic findings, and outcomes after spinal decompression in B-cell lymphoma. SUMMARY OF BACKGROUND DATA: B-cell lymphoma is a potential cause of spinal cord compression that presents ambiguously with nonspecific symptoms and variable imaging findings. Surgical decompression is a mainstay for both diagnosis and management, especially in patients with acute neurological deficits; however, the efficacy of surgical intervention compared with nonoperative management is still unclear. METHODS: The databases of Medline, PubMed, and the Cochrane Database of Systemic Reviews were queried for all articles reporting spinal B-cell lymphoma. Data on presenting symptoms, treatments, survival outcomes, and histologic markers were extracted. Using the R software "survival" package, we generated bivariate and multivariate Cox survival regression models and Kaplan-Meier curves. RESULTS: In total, 65 studies were included with 72 patients diagnosed with spinal B-cell lymphoma. The mean age was 56.22 (interquartile range: 45.00-70.25) with 68% of patients being males and 4.2% of patients being immunocompromised. Back pain was the most common symptom (74%), whereas B symptoms and cauda equina symptoms were present in 6% and 29%, respectively. The average duration of symptoms before presentation was 3.81 months (interquartile range: 0.45-3.25). The most common location was the thoracic spine (53%), with most lesions being hyperintense (28%) on T2 magnetic resonance imaging. Surgical resection was performed in 83% of patients. Symptoms improved in 91% of patients after surgery and in 80% of patients treated nonoperatively. For all 72 patients, the overall survival at 1 and 5 years was 85% (95% CI: 0.749-0.953; n = 72) and 66% (95% CI: 0.512-0.847; n = 72), respectively. CONCLUSION: Although surgery is usually offered in patients with acute spinal cord compression from B-cell lymphoma, chemotherapy and radiation alone offer a hopeful alternative to achieve symptomatic relief, particularly in patients who are unable to undergo surgery.

Malignant Carotid Paraganglioma: A Case Report.

Carotid body tumors (CBTs) are rare neoplasms of the neuroectoderm accounting for 0.6% of head and neck tumors, with a 2%-12.5% risk of malignancy. While surgical resection has been associated with a high rate of neurologic and vascular complications, it remains the mainstay of treatment for malignant CBTs. We present the case of a 40-year-old female with a 5-year history of progressively enlarging right-sided neck mass, with MRI and MRA showing a Shamblin grade III CBT encasement of the internal carotid artery (ICA). Blood flow was absent in the petrous segment of ICA, with great collateralization of brain blood supply, enabling en bloc resection of the tumor with a carotid bulb and ligation of the common carotid artery (CCA) without vascular reconstruction. Further, we describe the characteristics and current management for malignant CBTs, including surgical management, pre-surgical embolization, and adjuvant radiation therapy.

Incidence, mechanism, and protective strategies for 2-year pelvic fixation failure after adult spinal deformity surgery with a minimum six-level fusion.

OBJECTIVE: The purpose of this study was to determine the incidence, mechanism, and potential protective strategies for pelvic fixation failure (PFF) within 2 years after adult spinal deformity (ASD) surgery. METHODS: Data for ASD patients (age ≥ 18 years, minimum of six instrumented levels) with pelvic fixation (S2-alar-iliac [S2AI] and/or iliac screws) with a minimum 2-year follow-up were consecutively collected (2015-2019). Patients with prior pelvic fixation were excluded. PFF was defined as any revision to pelvic screws, which may include broken rods across the lumbosacral junction requiring revision to pelvic screws, pseudarthrosis across the lumbosacral junction requiring revision to pelvic screws, a broken or loose pelvic screw, or sacral/iliac fracture. Patient information including demographic data and health history (age, sex, BMI, smoking status, American Society of Anesthesiologists score, osteoporosis), operative (total instrumented levels [TIL], three-column osteotomy [3CO], interbody fusion), screw (iliac, S2AI, length, diameter), rod (diameter, kickstand), rod pattern (number crossing lumbopelvic junction, lowest instrumented vertebra [LIV] of accessory rod[s], lateral connectors, dual-headed screws), and pre- and postradiographic (lumbar lordosis, pelvic incidence, pelvic tilt, major Cobb angle, lumbosacral fractional curve, C7 coronal vertical axis [CVA], T1 pelvic angle, C7 sagittal vertical axis) parameters was collected. All rods across the lumbosacral junction were cobalt-chrome. All iliac and S2AI screws were closed-headed tulips. Both univariate and multivariate analyses were performed to determine risk factors for PFF. RESULTS: Of 253 patients (mean age 58.9 years, mean TIL 13.6, 3CO 15.8%, L5-S1 interbody 74.7%, mean pelvic screw diameter/length 8.6/87 mm), the 2-year failure rate was 4.3% (n = 11). The mechanisms of failure included broken rods across the lumbosacral junction (n = 4), pseudarthrosis across the lumbosacral junction requiring revision to pelvic screws (n = 3), broken pelvic screw (n = 1), loose pelvic screw (n = 1), sacral/iliac fracture (n = 1), and painful/prominent pelvic screw (n = 1). A higher number of rods crossing the lumbopelvic junction (mean 3.8 no failure vs 2.9 failure, p = 0.009) and accessory rod LIV to S2/ilium (no failure 54.2% vs failure 18.2%, p = 0.003) were protective for failure. Multivariate analysis demonstrated that accessory rod LIV to S2/ilium versus S1 (OR 0.2, p = 0.004) and number of rods crossing the lumbar to pelvis (OR 0.15, p = 0.002) were protective, while worse postoperative CVA (OR 1.5, p = 0.028) was an independent risk factor for failure. CONCLUSIONS: The 2-year PFF rate was low relative to what is reported in the literature, despite patients undergoing long fusion constructs for ASD. The number of rods crossing the lumbopelvic junction and accessory rod LIV to S2/ilium relative to S1 alone likely increase construct stiffness. Residual postoperative coronal malalignment should be avoided to reduce PFF.

How common is acute pelvic fixation failure after adult spine surgery? A single-center study of 358 patients.

OBJECTIVE: There is a paucity of literature on pelvic fixation failure after adult spine surgery in the early postoperative period. The purpose of this study was to determine the incidence of acute pelvic fixation failure in a large single-center study and to describe the lessons learned. METHODS: The authors performed a retrospective review of adult (≥ 18 years old) patients who underwent spinal fusion with pelvic fixation (iliac, S2-alar-iliac [S2AI] screws) at a single academic medical center between 2015 and 2020. All patients had a minimum of 3 instrumented levels. The minimum follow-up was 6 months after the index spine surgery. Patients with prior pelvic fixation were excluded. Acute pelvic fixation failure was defined as revision of the pelvic screws within 6 months of the primary surgery. Patient demographics and operative, radiographic, and rod/screw parameters were collected. All rods were cobalt-chrome. All iliac and S2AI screws were closed-headed screws. RESULTS: In 358 patients, the mean age was 59.5 ± 13.6 years, and 64.0% (n = 229) were female. The mean number of instrumented levels was 11.5 ± 5.5, and 79.1% (n = 283) had ≥ 6 levels fused. Three-column osteotomies were performed in 14.2% (n = 51) of patients, and 74.6% (n = 267) had an L5-S1 interbody fusion. The mean diameter/length of pelvic screws was 8.5/86.6 mm. The mean number of pelvic screws was 2.2 ± 0.5, the mean rod diameter was 6.0 ± 0 mm, and 78.5% (n = 281) had > 2 rods crossing the lumbopelvic junction. Accessory rods extended to S1 (32.7%, n = 117) or S2/ilium (45.8%, n = 164). Acute pelvic fixation failure occurred in 1 patient (0.3%); this individual had a broken S2AI screw near the head-neck junction. This 76-year-old woman with degenerative lumbar scoliosis and chronic lumbosacral zone 1 fracture nonunion had undergone posterior instrumented fusion from T10 to pelvis with bilateral S2AI screws (8.5 × 90 mm); i.e., transforaminal lumbar interbody fusion L4-S1. The patient had persistent left buttock pain postoperatively, with radiographically confirmed breakage of the left S2AI screw 68 days after surgery. Revision included instrumentation removal at L2-pelvis and a total of 4 pelvic screws. CONCLUSIONS: The acute pelvic fixation failure rate was exceedingly low in adult spine surgery. This rate may be the result of multiple factors including the preference for multirod (> 2), closed-headed pelvic screw constructs in which large-diameter long screws are used. Increasing the number of rods and screws at the lumbopelvic junction may be important factors to consider, especially for patients with high risk for nonunion.

Revision Thoracic Syringo-Subarachnoid Shunt for Recurrent Syrinx With Syringobulbia: Technique and Surgical Video.

Syringomyelia and syringobulbia continue to remain a diagnosis without widely accepted treatment paradigms. Furthermore, the currently available treatment options can be complicated by delayed symptom recurrence and the need for revision surgery. Revision intradural surgery is challenging, and currently, there is a paucity of literature describing safe techniques for revision syringotomy and shunt placement. In this technical report, we present a surgical video describing the technique of revision syringo-subarachnoid shunt placement in a 61-year-old female with a history of multiple intradural surgeries who presented with progressively symptomatic ascending syringobulbia.

History of Bone Grafts in Spine Surgery.

Bone grafting replaces damaged or missing bone with new bone and is used for surgical arthrodesis. Patients benefit from a huge variety of bone graft techniques and options for spinal fusions. This article reviews the rich history of bone grafts in surgery with particular emphasis on spinal fusion. During the early years of bone grafting in spine surgery, bone grafts were used on tuberculosis patients, and the structural support of the graft was most the important consideration. Between 1960 and 2000, many advances were made, specifically in the use of bone graft substitutes. The field of bone grafts in spine surgery has evolved rapidly since first described.

An Anatomical Method for Rib Disconnection During Posterior Costotransversectomy for Paravertebral Access to the Ventral Thoracic Spine.

OBJECTIVE: Posterior costotransversectomy in the thoracic spine is commonly used for degenerative diseases, tumors, trauma, and other operative indications. It involves resection of the rib head after the ligamentous complexes have been disconnected from the transverse process and lateral vertebral body. The current literature provides only vague descriptions of the steps involved in rib disconnection with respect to posterior costotransversectomy. METHODS AND RESULTS: Through cadaveric studies and in vivo application, a stepwise method for rib disconnection is described. CONCLUSIONS: This manuscript is the first to outline an anatomical method for rib disconnection during costotransversectomy.

Long-term clinical outcome of minimally invasive versus open single-level transforaminal lumbar interbody fusion for degenerative lumbar diseases: a meta-analysis.

BACKGROUND CONTEXT: Minimally invasive surgical transforaminal lumbar interbody fusion (MIS-TLIF) was developed in addition to open-TLIF to minimize iatrogenic soft-tissue damage. A potential disadvantage of MIS-TLIF is inadequate visualization, which may lead to incomplete neural decompression and a less robust arthrodesis. This may cause long-term problems and result in decreased patient satisfaction. PURPOSE: To evaluate the long-term clinical outcome, measured by patient-reported outcomes (PROMs), of patients with degenerative lumbar diseases treated with single-level TLIF (open vs. minimally invasive) with a minimum follow-up of 2-years. STUDY DESIGN: Meta-analysis. METHODS: The systematic review was conducted according to the PRISMA guidelines. Relevant studies were identified from Pubmed, MEDLINE, EMBASE, Scopus, Web of Science, and CENTRAL from the date of inception to August 2019. The inclusion criteria were (1) longitudinal comparative studies of MIS-TLIF versus open-TLIF approach for degenerative spine disease (2) outcomes reported as PROMs, (3) minimum follow-up of 2-years. RESULTS: Sixteen studies were included in the analysis. In total, 1,321 patients were included (660 MIS-TLIF& 661 open-TLIF). The following PROMS were analyzed: EQ-5D, SF, ODI, and VAS. Both techniques resulted in significant improvement in PROM, which remained significant at 2-years follow-up. However, no significant differences were found in all PROMs at 2-years follow-up. Both treatments resulted in a high rate of spinal fusion (80.5% vs. 91.1%; p=.29) and low rate of reoperation (3.0% vs. 2.4%; p=.50) or adjacent segment disease (12.6% vs. 12.40%; p=.50). CONCLUSIONS: MIS-TLIF and open-TLIF have comparable long-term clinical outscomes. Both operations can significantly reduce pain and positively improve PROMs. No significant differences were found between both treatments in clinical outcomes at a follow-up of minimal 2-years. Therefore, MIS-TLIF seems to be an effective and safe alternative to traditional open-TLIF in the long-term.

Arachnoid Web Fenestration: Diagnostic and Surgical Nuances.

Arachnoid web (AW) is a rare phenomenon that has only been described in small case reports and case series,1 most commonly presenting with upper motor neuron signs and subtle radiographic findings, such as the classically described "scalpel sign."2 In this report, we demonstrate the use of imaging and operative techniques that have not been previously shown in the literature as a video for AW. These include high-definition magnetic resonance imaging (MRI) sequences for preoperative diagnosis, use of intraoperative ultrasonography for identification of adhesions, and operative technique for AW fenestration (Video 1). The patient consented to this manuscript. A 64-year-old female patient developed progressive difficulty with balance and ambulation that particularly worsened over the last 4 months associated with tingling and numbness in the bilateral lower extremities. Physical examination revealed spastic gait and upper motor neuron signs in the lower extremities along with left foot drop. MRI revealed a chronic noncontrast-enhancing intramedullary lesion, along with a spinal cord indentation at the level T6 with an associated fiber between the cord and the posterior dura. Surgical intervention was performed with the use of intraoperative fluoroscopy and ultrasound for real-time identification of the surgical site and the AW. Under the microscope, the dura was incised while preserving the arachnoid. The AW was carefully dissected, leaving the portions that were tethered onto the cord. Two weeks postoperatively, the patient's gait was markedly improved, with resolved neurologic function in the lower extremities. Follow-up MRI at 3 months demonstrated resolved medullary syrinx and normalization of the spinal cord contour.

The pharyngeal plexus: an anatomical review for better understanding postoperative dysphagia.

The pharyngeal plexus is an essential anatomical structure, but the contributions from the glossopharyngeal and vagus nerves and the superior cervical ganglion that give rise to the pharyngeal plexus are not fully understood. The pharyngeal plexus is likely to be encountered during various anterior cervical surgical procedures of the neck such as anterior cervical discectomy and fusion. Therefore, a detailed understanding of its anatomy is essential for the surgeon who operates in and around this region. Although the pharyngeal plexus is an anatomical structure that is widely mentioned in literature and anatomy books, detailed descriptions of its structural nuances are scarce; therefore, we provide a comprehensive review that encompasses all the available data from this critical structure. We conducted a narrative review of the current literature using databases like PubMed, Embase, Ovid, and Cochrane. Information was gathered regarding the pharyngeal plexus to improve our understanding of its anatomy to elucidate its involvement in postoperative spine surgery complications such as dysphagia. The neural contributions of the cranial nerves IX, X, and superior sympathetic ganglion intertwine to form the pharyngeal plexus that can be injured during ACDF procedures. Factors like surgical retraction time, postoperative hematoma, surgical hardware materials, and profiles and smoking are related to postoperative dysphagia onset. Thorough anatomical knowledge and lateral approaches to ACDF are the best preventing measures.

Total Anterior Uncinatectomy During Anterior Discectomy and Fusion for Recurrent Cervical Radiculopathy: A Two-dimensional Operative Video and Technical Report.

A common cause of cervical radiculopathy from degenerative foraminal stenosis is severe uncovertebral hypertrophy. It is difficult to accomplish complete foraminal decompression in these cases with posterior techniques without the removal of a large portion of the facet joint. Total removal of the uncovertebral joint from an anterior approach allows for complete decompression of the exiting cervical nerve root and has been shown to be a safe technique. In this surgical video and technical report, we demonstrate the surgical anatomy and operative technique of a two-level anterior uncinatectomy during anterior discectomy and fusion (ACDF) for recurrent cervical radiculopathy after a previous multi-level posterior foraminotomy. The patient is a 67-year-old male with a progressive left arm and neck pain with radiographic, clinical, and electrophysiologic diagnostic evidence of active C6 and C7 radiculopathies from degenerative foraminal stenosis at the C5-6 and C6-7 levels. Posterior foraminotomies had been performed without significant improvement in his radicular pain. A repeat MRI demonstrated lateral foraminal stenosis from severe uncovertebral joint hypertrophy at the C5-6 and C6-7 levels. After acquiring informed consent from the patient, an anterior approach was performed with complete removal of the uncovertebral joints at both levels with discectomy and fusion. Postoperatively, the patient had complete resolution of his radicular pain and remained pain-free at the latest follow-up. Complete uncinatectomy and ACDF is an effective technique for complete foraminal decompression in cases of refractory radiculopathy and neck pain after unsuccessful posterior decompression.

Cost-Effective Method for 3-Dimensional Printing Dynamic Multiobject and Patient-Specific Brain Tumor Models: Technical Note.

BACKGROUND: Three-dimensional (3D) printing is a powerful tool for replicating patient-specific anatomic features for education and surgical planning. The advent of "desktop" 3D printing has created a cost-effective and widely available means for institutions with limited resources to implement a 3D-printing workflow into their clinical applications. The ability to physically manipulate the desired components of a "dynamic" 3D-printed model provides an additional dimension of anatomic understanding. There is currently a gap in the literature describing a cost-effective and time-efficient means of creating dynamic brain tumor 3D-printed models. METHODS: Using free, open-access software (3D Slicer) for patient imaging to Standard Tessellation Language file conversion, as well as open access Standard Tessellation Language editing software (Meshmixer), both intraaxial and extraaxial brain tumor models of patient-specific pathology are created. RESULTS: A step-by-step methodology and demonstration of the software manipulation techniques required for creating cost-effective, multidimensional brain tumor models for patient education and surgical planning are exhibited using a detailed written guide, images, and a video display. CONCLUSIONS: In this technical note, we describe in detail the specific functions of free, open-access software and desktop 3D printing techniques to create dynamic and patient-specific brain tumor models for education and surgical planning.

The SpineBox: A Freely Available, Open-access, 3D-printed Simulator Design for Lumbar Pedicle Screw Placement.

Background The recent COVID-19 pandemic has demonstrated the need for innovation in cost-effective and easily produced surgical simulations for trainee education that are not limited by physical confines of location. This can be accomplished with the use of desktop three-dimensional (3D) printing technology. This study describes the creation of a low-cost and open-access simulation for anatomical learning and pedicle screw placement in the lumbar spine, which is termed the SpineBox. Materials and methods An anonymized CT scan of the lumbar spine was obtained and converted into 3D software files of the L1-L5 vertebral bodies. A computer-assisted design (CAD) software was used to assemble the vertebral models into a simulator unit in anatomical order to produce an easily prototyped simulator. The printed simulator was layered with foam in order to replicate soft tissue structures. The models were instrumented with pedicle screws using standard operative technique and examined under fluoroscopy. Results Ten SpineBoxes were created using a single desktop 3D printer, with accurate replication of the cortico-cancellous interface using previously validated techniques. The models were able to be instrumented with pedicle screws successfully and demonstrated quality representation of bony structures under fluoroscopy. The total cost of model production was under $10. Conclusion The SpineBox represents the first open-access simulator for the instruction of spinal anatomy and pedicle screw placement. This study aims to provide institutions across the world with an economical and feasible means of spine surgical simulation for neurosurgical trainees and to encourage other rapid prototyping laboratories to investigate innovative means of creating educational surgical platforms in the modern era.

Orientation Planning in the Fused Deposition Modeling 3D Printing of Anatomical Spine Models.

Three-dimensional (3D) printing has revolutionized medical training and patient care. Clinically it is used for patient-specific anatomical modeling with respect to surgical procedures. 3D printing is heavily implemented for simulation to provide a useful tool for anatomical knowledge and surgical techniques. Fused deposition modeling (FDM) is a commonly utilized method of 3D printing anatomical models due to its cost-effectiveness. A potential disadvantage of FDM 3D printing complex anatomical shapes is the limitations of the modeling system in providing accurate representations of multifaceted ultrastructure, such as the facets of the lumbar spine. In order to utilize FDM 3D printing methods in an efficient manner, the pre-printing G-code assembly must be oriented according to the anatomical nature of the print. This article describes the approach that our institution's 3D printing laboratory has used to manipulate models' printing angles in regard to the print bed and nozzle, according to anatomical properties, thus creating quality and cost-effective anatomical spine models for education and procedural simulation.

Ex vivo virtual and 3D printing methods for evaluating an anatomy-based spinal instrumentation technique for the 12th thoracic vertebra.

INTRODUCTION: Three-dimensional printing and virtual simulation both provide useful methods of patient-specific anatomical modeling for assessing and validating surgical techniques. A combination of these two methods for evaluating the feasibility of spinal instrumentation techniques based on anatomical landmarks has not previously been investigated. MATERIALS AND METHODS: Nineteen anonymized CT scans of the thoracic spine in adult patients were acquired. Maximum pedicle width and height were recorded, and statistical analysis demonstrated normal distributions. The images were converted into standard tessellation language (STL) files, and the T12 vertebrae were anatomically segmented. The intersection of two diagonal lines drawn from the lateral and medial borders of the T12 transverse process (TP) to the lateral border of the pars and inferolateral portion of the TP was identified on both sides of each segmented vertebra. A virtual screw was created and insertion into the pedicle on each side was simulated using the proposed landmarks. The vertebral STL files were then 3D-printed, and 38 pedicles were instrumented according to the individual posterior landmarks used in the virtual investigation. RESULTS: There were no pedicle breaches using the proposed anatomical landmarks for insertion of T12 pedicle screws in the virtual simulation component. The technique was further validated by additive manufacturing of individual T12 vertebrae and demonstrated no breaches or model failures during live instrumentation using the proposed landmarks. CONCLUSIONS: Ex vivo modeling through virtual simulation and 3D printing provides a powerful and cost-effective means of replicating vital anatomical structures for investigation of complex surgical techniques.

Clinical implications of nervus intermedius variants in patients with geniculate neuralgia: Let anatomy be the guide.

Geniculate neuralgia (GN) is an uncommon, but severe, condition that is characterized by excruciating paroxysmal pain in the seventh cranial nerve's cutaneous distribution of general somatic afferent fibers carried through the nervus intermedius (NI). GN becomes a surgical disease in refractory cases of pain after exhaustive medical management. Surgical intervention in the form of microvascular decompression and nerve sectioning has been investigated with good patient outcomes. Despite this, there are limited guidelines on either technique's appropriateness in specific operative scenarios. In our 30-year experience in GNs surgical management, we have found that a detailed knowledge of the NIs anatomy, variants, and intraoperative surgical anatomic findings are the key to choosing the most appropriate intervention, and may provide the answer to why some patients fail to experience pain relief after surgery. These anatomic variants also may explain why many patients commonly do not experience side effects related to the visceral efferent and special afferent fibers after nerve sectioning.

Iatrogenic Lumbar Arachnoid Cyst Fenestration for Tethered Cord: 2-Dimensional Operative Video.

Iatrogenic lumbar arachnoid cysts are a rare occurrence after intradural surgery.1,2 To our knowledge, there is only 1 other previous case reported in the literature contributing to a symptomatic tethered cord.3 We present a surgical video (Video 1) demonstrating the history, preoperative workup, and operative technique for exploration and fenestration of a symptomatic iatrogenic lumbar arachnoid cyst with a tethered cord. The patient is a 57-year-old female with a history of a closed neural tube defect with a lipoma that was resected over 20 years before her evaluation. She was lost to follow-up and did not retain any previous medical documentation. She complained of a 2-month history of progressive bilateral lower extremity weakness, leg pain, and worsening of chronic urinary incontinence. Imaging demonstrated a cystic lesion compressing her conus and cauda equina at the L3-4 level. The risks, benefits, and alternatives were discussed, and the patient elected to proceed with surgery. Intraoperative findings demonstrated a complex multiloculated arachnoid cyst with tethering of the conus. The cysts were dissected from the conus and fenestrated, allowing spontaneous flow of cerebrospinal fluid and conus pulsations. Biopsy of the cyst wall confirmed the diagnosis of arachnoid cyst without neoplastic tissue. Due to the presence of multiple loculations, primary pial closure could not be performed. Thus, a circumferential detethering of the conus was performed to ensure complete decompression of the neural elements. Postoperatively, the patient demonstrated improvement in her bilateral lower extremity pain and weakness. Magnetic resonance imaging was scheduled during routine follow-up at 3 months.