Minimally Invasive Techniques in the Surgical Management of Traumatic Pediatric Thoracolumbar Fractures.

BACKGROUND: Thoracolumbar (TL) fractures are uncommon in children. While surgical treatment is recommended for unstable TL fractures, there is no consensus on appropriate surgical treatment. We present a case series of pediatric patients with traumatic TL fractures treated with minimally invasive techniques. We discuss our early experience and technical challenges with navigation and robotic-assisted fixation. METHODS: A retrospective review of a prospectively maintained trauma database from February 2018 to February 2023 of all pediatric patients (<18 years old) undergoing percutaneous fixation for unstable TL fractures was performed. Minimally invasive techniques included fluoroscopy and/or navigation-guided or robotic-assisted surgery. Clinical course, radiographic findings, and technical challenges were reviewed. RESULTS: A cohort of 12 patients (age range, 4-17 years) with 6 (50%) Chance fractures, 2 (16%) pars fractures, 2 (16%) pedicle fracture, 1 (8%) burst fracture, and 1 (8%) other fracture were identified. Nine patients had fractures involving the lumbar spine, and the remaining 3 had thoracic fractures. In all cases, percutaneous pedicle screws were placed above and below the fracture with the use of neuronavigation or robotic-assisted navigation (n = 2). Blood loss was <30 mL for single-level fractures and instrumented fusion. Two patients had hardware-related complications. At follow-up (mean 9.67 months after surgery), patients were doing well clinically, and most imaging showed stable alignment. CONCLUSIONS: Our early experience shows that short segment instrumentation through a minimally invasive approach is a safe and effective surgical option for young pediatric patients with good clinical outcomes and favorable radiographic postoperative finding.

Intraoperative Ultrasound: Real-Time Surgical Adjunct for Complete Resection of Spinal Arachnoid Webs.

Spinal arachnoid webs are abnormal formations of arachnoid membranes that reside in the arachnoid space. Clinically, they may present as an incidental finding or in patients with progressively worsening myelopathy. Early detection and surgical intervention are recommended in patients with progressive symptoms. Several methods have been described for the surgical treatment of these web formations.1-4 The success of surgery and the ability to prevent recurrence is dependent on complete surgical resection of these lesions, which in some cases can appear complex and intricate in nature. A few reports have highlighted the use of intraoperative ultrasound to localize the lesion; however, none have highlighted its value in establishing successful web resection and restoration of normal cerebrospinal fluid flow.3,4 Herein, we demonstrate the use of intraoperative ultrasound as an effective adjunct to assessing and establishing complete resection of arachnoid webs. We illustrate how intraoperative ultrasound allows for real-time, direct visualization of arachnoid lysis with restoration of normal cerebrospinal fluid flow (Video 1). Our patient was symptomatic for 12 months with rapid progression of myelopathic symptoms in the 3 months before presentation. Following surgery, she remained asymptomatic at 4-year follow-up with no reoccurrence at 24-month magnetic resonance imaging. Intraoperative ultrasound is a useful adjunct to successfully performing dorsal arachnoid web surgery and ensuring improved surgical outcomes through complete web resection and decompression of the spinal cord.

Autoimmune diseases of the spine and spinal cord.

Magnetic resonance imaging (MRI) and clinicopathological tools have led to the identification of a wide spectrum of autoimmune entities that involve the spine. A clearer understanding of the unique imaging features of these disorders, along with their clinical presentations, will prove invaluable to clinicians and potentially limit the need for more invasive procedures such as tissue biopsies. Here, we review various autoimmune diseases affecting the spine and highlight salient imaging features that distinguish them radiologically from other disease entities.

Laminoplasty versus laminectomy with fusion for treating multilevel degenerative cervical myelopathy.

Background: Laminectomy with fusion (LF) and laminoplasty (LP) are common posterior decompression procedures used to treat multilevel degenerative cervical myelopathy (DCM). There is debate on their relative efficacy and safety for treatment of DCM. The goal of this study is to examine outcomes and costs of LF and LP procedures for DCM. Methods: This is a retrospective review of adult patients (<18) at a single center who underwent elective LP and LF of at least 3 levels from C3-C7. Outcome measures included operative characteristics, inpatient mobility status, length of stay, complications, revision surgery, VAS neck pain scores, and changes in radiographic alignment. Oral opioid analgesic needs and hospital cost comparison were also assessed. Results: LP cohort (n=76) and LF cohort (n=59) reported no difference in neck pain at baseline, 1, 6, 12, and 24 months postoperatively (p>.05). Patients were successfully weaned off opioids at similar rates (LF: 88%, LP: 86%). Fixed and variable costs respectively with LF cases hospital were higher, 15.7% and 25.7% compared to LP cases (p=.03 and p<.001). LF has a longer length of stay (4.2 vs. 3.1 days, p=.001). Wound-related complications were 5 times more likely after LF (13.6% vs. 5.9%, RR: 5.15) and C5 palsy rates were similar across the groups (LF: 11.9% LP: 5.6% RR: 1.8). Ground-level falls requiring an emergency department visit were more likely after LF (11.9% vs. 2.6%, p=.04). Conclusions: When treating multilevel DCM, LP has similar rates of new or increasing axial neck pain compared to LF. LF was associated with greater hospital costs, length of stay, and complications compared to LP. LP may in fact be a less morbid and more cost-effective alternative to LF for patients without cervical deformity.

Traumatic bilateral lumbosacral facet dislocation without fracture: illustrative case.

BACKGROUND: Traumatic bilateral lumbosacral facet dislocations without fractures are extremely rare. Only 7 cases have been documented since the first description by Watson-Jones in 1974. Although various treatment strategies have been reported, no consensus has been reached regarding the best surgical approach. OBSERVATIONS: A 35-year-old female presented for medical attention following a high-speed motor vehicle collision. She sustained multiple injuries, including an abdominal aortic injury requiring emergent thoracic endovascular aortic repair. She was found to have bilateral lumbosacral dislocation without fracture (L5-S1) and was noted to be neurologically intact. Once medically stabilized, the patient was taken to the operating room for minimally invasive reduction and stabilization of her lumbosacral spine. Postoperatively, the patient was neurologically intact and remained stable with no deficits and appropriate lumbosacral alignment throughout her 2-year follow-up. LESSONS: The authors report a minimally invasive approach to the management of bilateral lumbosacral facet dislocation without fracture. Although conventional open approaches have been described previously, consideration should be given to minimally invasive strategies in select patients to facilitate their rehabilitative postoperative course.

Potential Role for Stem Cell Regenerative Therapy as a Treatment for Degenerative Disc Disease and Low Back Pain: A Systematic Review.

Back pain is the single leading cause of disability worldwide. Despite the prevalence and morbidity of lower back pain, we still lack a gold-standard treatment that restores the physiological function of degenerated intervertebral discs. Recently, stem cells have emerged as a promising strategy for regenerative therapy for degenerative disc disease. In this study, we review the etiology, pathogenesis, and developing treatment strategies for disc degeneration in low back pain with a focus on regenerative stem cell therapies. A systematic search of PubMed/MEDLINE/Embase/Clinical Trials.gov databases was conducted for all human subject abstracts or studies. There was a total of 10 abstracts and 11 clinical studies (1 RCT) that met the inclusion criteria. The molecular mechanism, approach, and progress of the different stem cell strategies in all studies are discussed, including allogenic bone marrow, allogenic discogenic cells, autologous bone marrow, adipose mesenchymal stem cells (MSCs), human umbilical cord MSC, adult juvenile chondrocytes, autologous disc derived chondrocytes, and withdrawn studies. Clinical success with animal model studies is promising; however, the clinical outcomes of stem cell regenerative therapy remain poorly understood. In this systematic review, we found no evidence to support its use in humans. Further studies on efficacy, safety, and optimal patient selection will establish whether this becomes a viable, non-invasive therapeutic option for back pain.

Exercise therapy guides cortical reorganization after midthoracic spinal contusion to enhance control of lower thoracic muscles, supporting functional recovery.

Postural control is critical for locomotion, allowing for gait changes, obstacle avoidance and navigation of rough terrain. A major problem after spinal cord injury (SCI) is regaining the control of balance to prevent falls and further injury. While the circuits for locomotor pattern generation reside in the spinal cord, postural control consists of multiple, complex networks that interact at the spinal, brainstem and cortical levels. After complete SCI, cortical reorganization establishes novel control of trunk musculature that is required for weight-supported stepping. In this study, we examined the impact of exercise therapy on cortical reorganization in the more clinically relevant models of both moderate and severe midthoracic contusion injury in the rat. Results demonstrate that both spontaneous recovery and therapy induced recovery of weight-supported stepping utilize cortical reorganization. Moreover, exercise therapy further improves outcome by enhancing cortical control of lower thoracic muscles enabling improvements in interlimb coordination associated with improved balance that increases weight-supported stepping. The outcome of this study suggest that cortical control of posture is key to functional improvement in locomotion. This information can be used to improve the timing and type of therapy after SCI by considering changes along the entire neural axis.

Patient Characteristics, Injury Types, and Costs Associated with Secondary Over-Triage of Isolated Cervical Spine Fractures.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: To aim of this study was to identify patient variables, injury characteristics, and costs associated with operative and non-operative treatment following inter-facility transfer of patients with isolated cervical spine fractures. SUMMARY OF BACKGROUND DATA: Patients with isolated cervical spine fractures are subject to inter-facility transfer for surgical assessment, yet are often treated nonoperatively. The American College of Surgeons' benchmark rate of "secondary over-triage" is <50%. Identifying patient and injury characteristics as well as costs associated with treatment following transfer of patients with isolated cervical spine fractures may help reduce rates of secondary over-triage and healthcare expenditures. METHODS: Patients transferred to a Level-1 trauma center with isolated cervical spine fractures between January 2015 and September 2020 were identified. Patient demographics, comorbidities, insurance data, injury characteristics, imaging workup, treatment, and financial data were collected for all patients. Multivariable logistic regression models were constructed to identify patient and injury characteristics associated with surgical treatment. RESULTS: Nearly 75% of patients were treated non-operatively. Over 97% of transfers were accepted by the general surgery trauma service. Multivariable modeling found that higher BMI, presence of any neurologic deficit including spinal cord or isolated spinal nerve root injuries, present smoking status, or cervical spine magnetic resonance imaging obtained post-transfer, were associated with surgical treatment for isolated cervical spine fractures. Among patients with type II dens fractures, increased fracture displacement was associated with surgical treatment. Median charges to patients treated operatively and nonoperatively were $380,890 and $90,734, respectively. Median hospital expenditures for patients treated operatively and nonoperatively were $55,115 and $12,131, respectively. CONCLUSION: A large proportion of patients with isolated cervical spine fractures are subject to over-triage. Injury characteristics are important for determining need for surgical treatment, and therefore interfacility transfer. Improving communication with spine surgeons when deciding to transfer patients may significantly reduce health care costs and resource use.Level of Evidence: 4.

The Unique Properties of Placental Mesenchymal Stromal Cells: A Novel Source of Therapy for Congenital and Acquired Spinal Cord Injury.

Spinal cord injury (SCI) is a devasting condition with no reliable treatment. Spina bifida is the most common cause of congenital SCI. Cell-based therapies using mesenchymal stem/stromal cells (MSCS) have been largely utilized in SCI. Several clinical trials for acquired SCI use adult tissue-derived MSC sources, including bone-marrow, adipose, and umbilical cord tissues. The first stem/stromal cell clinical trial for spina bifida is currently underway (NCT04652908). The trial uses early gestational placental-derived mesenchymal stem/stromal cells (PMSCs) during the fetal repair of myelomeningocele. PMSCs have been shown to exhibit unique neuroprotective, angiogenic, and antioxidant properties, all which are promising applications for SCI. This review will summarize the unique properties and current applications of PMSCs and discuss their therapeutic role for acquired SCI.

Neuroimaging findings and pathophysiology of dorsal spinal arachnoid webs: illustrative case.

BACKGROUND: Spinal arachnoid webs are uncommon and difficult to diagnose, especially because causative intradural transverse bands of arachnoid tissue are radiographically occult. Left untreated, arachnoid webs may cause progressive, debilitating, and permanent neurological dysfunction. Conversely, more than 90% of patients may experience rapid neurological recovery after resection, even with a prolonged duration of presenting symptoms. Indirect imaging signs such as spinal cord indentation and compression with cerebrospinal fluid (CSF) flow alteration provide crucial diagnostic clues that are critical in guiding appropriate management of such patients. OBSERVATIONS: The authors reported a patient with no significant medical history who presented with back pain, progressive lower extremity weakness, gait ataxia, and bowel and bladder incontinence. They discussed multimodality imaging for determining the presence of arachnoid webs, including magnetic resonance imaging, phase-contrast CSF flow study, computed tomography myelography, and intraoperative ultrasound. They also discussed the detailed anatomy of the spinal subarachnoid space and a plausible pathophysiological mechanism for dorsal arachnoid webs. LESSONS: The authors report on a patient who underwent comprehensive imaging evaluation detailing the arachnoid web and whose subsequent anatomical localization and surgical treatment resulted in a full neurological recovery.

Headache Relief Is Maintained 7 Years After Anterior Cervical Spine Surgery: Post Hoc Analysis From a Multicenter Randomized Clinical Trial and Cervicogenic Headache Hypothesis.

OBJECTIVE: To evaluate whether anterior cervical spine surgery offers sustained (7 years) relief in patients with cervicogenic headaches (CGHs), and evaluate the difference between cervical disc arthroplasty (CDA) and anterior cervical discectomy and fusion (ACDF) for 1 and 2-level surgeries from a multicenter randomized clinical trial. METHODS: A post hoc analysis was performed of 575 patients who underwent one or 2-level CDA or ACDF for symptomatic cervical spondylosis as part of a prospective randomized clinical trial. Assessment of pain and functional outcome was done with the Neck Disability Index (NDI) in the trial. We used the NDI headache component to assess headache outcome. RESULTS: For both 1- and 2-level CDA and ACDF groups, there was significant headache improvement from preoperative baseline out to 7 years (p < 0.0001). For 1-level surgeries, headache improvement was similar for both groups at the 7-year point. For 2-level treatment, CDA patients had significantly improved headache scores versus ACDF patients at the 7-year point (p = 0.016). CONCLUSION: The headache improvement noted at early follow-up was sustained over the long-term period with ACDF and CDA populations. In the case of 2-level operations, CDA patients demonstrated significantly greater benefit compared to ACDF patients over the long-term. Sinuvertebral nerve irritation at the unco-vasculo-radicular junction and anterior dura may be the cause of CGH. Therefore, it is possible that improved cervical kinematics and preservation of range of motion at adjacent uncovertebral joints in CDA may contribute to the observed difference between the groups.

Serum lactate as a potential biomarker of non-glial brain tumors.

We assess whether serum lactate is a potential biomarker for non-glial cell brain tumors. Rapidly growing tumor cells typically have glycolytic rates up to 200 times higher than those of their normal tissues of origin and produce lactate even in the presence of oxygen. This phenomenon is called the Warburg effect. We recently showed that serum lactate levels can be used as a potential non-invasive biomarker in glial cell brain tumors, which correlates with both tumor grade and the extent of malignancy. In the present study, we found that patients with metastatic brain tumors had significantly higher baseline serum lactate levels compared to patients with meningioma and pituitary tumors. There was a statistically significant association between metastatic brain tumors and elevated serum lactate. We demonstrate that lactate can be used as a non-invasive biomarker to determine malignancy for brain tumors. Further analyses of larger populations will be needed to establish the value of serum lactate in determining the response to therapy or early recurrence.

Gamma knife radiosurgery for the treatment of cystic cerebral metastases.

PURPOSE: To assess the role of Gamma Knife radiosurgery (GKRS) in the treatment of nonsurgical cystic brain metastasis, and to determine predictors of response to GKRS. METHODS: We reviewed a prospectively maintained database of brain metastases patients treated at our institution between 2006 and 2010. All lesions with a cystic component were identified, and volumetric analysis was done to measure percentage of cystic volume on day of treatment and consecutive follow-up MRI scans. Clinical, radiologic, and dosimetry parameters were reviewed to establish the overall response of cystic metastases to GKRS as well as identify potential predictive factors of response. RESULTS: A total of 111 lesions in 73 patients were analyzed; 57% of lesions received prior whole-brain radiation therapy (WBRT). Lung carcinoma was the primary cancer in 51% of patients, 10% breast, 10% colorectal, 4% melanoma, and 26% other. Fifty-seven percent of the patients were recursive partitioning analysis class 1, the remainder class 2. Mean target volume was 3.3 mL (range, 0.1-23 mL). Median prescription dose was 21 Gy (range, 15-24 Gy). Local control rates were 91%, 63%, and 37% at 6, 12, and 18 months, respectively. Local control was improved in lung primary and worse in patients with prior WBRT (univariate). Only lung primary predicted local control in multivariate analysis, whereas age and tumor volume did not. Lesions with a large cystic component did not show a poorer response compared with those with a small cystic component. CONCLUSIONS: This study supports the use of GKRS in the management of nonsurgical cystic metastases, despite a traditionally perceived poorer response. Our local control rates are comparable to a matched cohort of noncystic brain metastases, and therefore the presence of a large cystic component should not deter the use of GKRS. Predictors of response included tumor subtype. Prior WBRT decreased effectiveness of SRS for local control rates.

Stereotactic radiosurgery for the treatment of melanoma and renal cell carcinoma brain metastases.

Renal cell carcinoma (RCC) and melanoma brain metastases have traditionally been considered radioresistant lesions when treated with conventional radiotherapeutic modalities. Radiosurgery provides high-dose radiation to a defined target volume with steep fall off in dose at lesion margins. Recent evidence suggests that stereotactic radiosurgery (SRS) is effective in improving local control and overall survival for a number of tumor subtypes including RCC and melanoma brain metastases. The purpose of this study was to compare the response rate to SRS between RCC and melanoma patients and to identify predictors of response to SRS for these 2 specific subtypes of brain metastases. We retrospectively reviewed a prospectively maintained database of all brain metastases treated with Gamma Knife SRS at the University Health Network (Toronto, Ontario) between October 2007 and June 2010, studying RCC and melanoma patients. Demographics, treatment history and dosimetry data were collected; and MRIs were reviewed for treatment response. Log rank, Cox proportional hazard ratio and Kaplan-Meier survival analysis using SPSS were performed. A total of 103 brain metastases patients (41 RCC; 62 melanoma) were included in the study. The median age, Karnofsky performance status score and Eastern Cooperative Oncology Group performance score was 52 years (range 27-81), 90 (range 70-100) and 1 (range 0-2), respectively. Thirty-four lesions received adjuvant chemotherapy and 56 received pre-SRS whole brain radiation therapy. The median follow-up, prescription dose, Radiation Therapy Oncology Group conformity index, target volume and number of shots was 6 months (range 1-41 months), 21 Gy (range 15-25 Gy), 1.93 (range 1.04-9.76), 0.4 cm3 (range 0.005-13.36 cm3) and 2 (range 1-22), respectively. Smaller tumor volume (P=0.007) and RCC pathology (P=0.04) were found to be positive predictors of response. Actuarial local control rate for RCC and melanoma combined was 89% at 6 months, 84% at 12 months, 76% at 18 months and 61% at 24 months. Local control at 12 months was 91 and 75% for RCC and melanoma, respectively. SRS is a valuable treatment option for local control of RCC and melanoma brain metastases. Smaller tumor volume and RCC pathology, predictors of response, suggest distinct differences in tumor biology and the extent of radioresponse between RCC and melanoma.

Current standards in the management of cerebral metastases.

The last 30 years have seen major changes in attitude toward patients with cerebral metastases. This paper aims to outline the major landmarks in this transition and the therapeutic strategies currently used. The controversies surrounding control of brain disease are discussed, and two emerging management trends are reviewed: tumor bed radiosurgery and salvage radiation.

Sellar glomangioma.

Glomus tumors of the sellar region are exceedingly rare with only two reported cases in the literature. A case of a sellar glomangioma in a 72-year-old man is described. The tumor had the radiographic and gross appearance of a pituitary adenoma. Microscopically, the tumor was composed of epithelioid cells surrounding prominent small vascular channels. The tumor cells had indistinct cell borders and monotonous nuclei. Histological and immunohistochemical analysis identified the sellar tumor as a glomangioma. Here, we report the clinicopathological features of a third case of a sellar glomus tumor and review the literature.

A RIP tide in neuronal signal transduction.

The generation of nuclear signaling proteins by regulated intramembrane proteolysis (RIP) is a new paradigm of signal transduction. Mammalian proteins that are processed by RIP include SREBP-1, Notch-1, amyloid precursor protein (APP), and ErbB-4. Intramembranous gamma-secretase cleavage of APP plays a central role in Alzheimer's disease by generating the amyloid beta protein. An intriguing possibility is that the cognate C-terminal fragment generated by gamma-secretase cleavage could also play a role through the regulation of nuclear signaling events. Thus, RIP may contribute to both brain development and degeneration and may provide unexpected diversity to the signaling repertoire of a cell.