Enhanced recovery after elective spinal surgery: an Australian pilot study.

Background: The principles of enhanced recovery after surgery (ERAS) aim to reduce the physiological stress of surgery which in turn improve clinical and health economic outcomes. There is ample evidence in literature supporting ERAS methodologies in other surgical specialties, but its adoption in spinal surgery, especially in Australia remains in infancy. The aim of this project is to describe the early experience with an evidence-based ERAS pathway for simple spine surgery, a first of its kind in Australia. Methods: An ERAS protocol was designed using an evidenced-based review of the literature. The authors then conducted a prospective cohort analysis looking at outcome of patients undergoing elective spinal (lumbar and cervical) decompression surgery under ERAS principles by a single surgeon on the Westmead Hospital Campus between March 2021 to May 2023. Primary outcomes were patient length of stay (LOS), patient reported pain and disability scores and complications (including readmissions within 30 days and re-operation within 6 months). Secondary outcomes included predictors of failure for same-day discharge. Results: A total of 52 patients underwent spinal decompression surgeries under the ERAS protocol. Overall 43 out of 52 patients (83.7%) were successfully discharged on the same day as their surgery. Patient reported outcomes were improved at 6 weeks and 6 months confirming durability of intervention. The rates of complications were similar to literature reported rates for simple lumbar or cervical decompression procedures and there were no readmissions within 30 days or re-operations within 6 months of surgery. Being of non-English speaking background [odds ratio (OR) =6.08, P=0.04] and from home alone (OR =10.25, P=0.03) were predictors of failure of same day discharge in this small cohort. Conclusions: Implementation of ERAS protocols for simple spinal decompression surgeries is feasible and produces durable improved patient outcomes while reducing LOS in hospitals. Patient social factors can be predictive of lack of compliance.

Spinal subdural haemorrhage secondary to strenuous exercise and warfarin, complicated by acute ischaemic stroke.

Spinal subdural haemorrhage or haematoma (SSDH) is a rare condition that is often overlooked and missed on initial presentation due to its non-specific features that may mimic other more common pathologies. It is associated with high morbidity and mortality rates, with few evidence-based management principles, particularly during the subacute stages of recovery. In this report, we detail a case of SSDH associated with exercise and anticoagulation therapy, which was complicated by acute ischaemic stroke. SSDH should be suspected in cases of acute back pain without a clear alternative cause, particularly in coagulopathic individuals. Following treatment, early recommencement of anticoagulation therapy may be justified in certain cases where indicated, after careful consideration of the affected individual's risk profile.

Wiltse Approach for Lumbar Microdiscectomy and Foraminotomy: 2-Dimensional Operative Video.

Far lateral disc herniations account for between 7% and 12% of all disk herniations and occur predominantly at L3/4 and L4/5.1,2 They can cause severe radicular pain due to dorsal root ganglion involvement and are exacerbated by lateral bending to the side of the lesion. Back pain is less of a feature with this pathology.3 The Wiltse approach was first described in the 1960s as an approach to L5/S1 noninstrumented fusion for isthmic spondylolisthesis4; its use in pedicle screws and far lateral discs was described in 1988.5 It has been shown to reduce muscle atrophy, wound infection, and blood loss.6,7 The Wiltse approach for a far lateral disc herniation provides a direct route to the disc pathology and as such is useful in cases with this isolated pathology. It confers less extensive muscle dissection and therefore less postoperative pain, minimal bone resection with preservation of the integrity of the facet joint, and it does not rely on endoscopy (rather the traditional operating microscope). It can also be used where endoscopy is contraindicated such as in revision cases. Here we present the case of a 53-year-old woman who presented with several weeks of back pain and right L3 radiculopathy, as well as right hip flexion and knee extension weakness. A Wiltse approach microdiscectomy was proposed for her far lateral disk herniation, and the patient consented to the procedure. At 6 weeks of follow-up, her radicular pain had resolved and there was improvement in hip flexion and knee extension. Image at 5:50 of Surgical Video is used with permissions from the Wiltse, L, Bateman, JD, Hutchinson, RH, and Nelson, WE. The Paraspinal Sacrospinalis-Splitting Approach to the Lumbar Spine. J Bone Joint Surg Am. 1968;50(5):919-926. Copyright © 1968 by The Journal of Bone and Joint Surgery, Inc.

Spinal intramedullary uterine carcinosarcoma metastasis.

Intramedullary spinal cord metastases (ISCM) are a rare and challenging manifestation of metastatic cancer that have devastating impacts on the individual's neurological function, survival expectancy and overall quality of life. Given the rarity and poor prognosis, there is a lack of consensus in management. Uterine carcinosarcoma itself is a rare cancer, accounting for less than 3% of all uterine cancers. It carries a poor prognosis, with only one-third of patients surviving beyond 5 years. There are no previous reports of uterine carcinosarcoma metastases to the spinal cord. Here, we present the case of a woman in her late 70s with a uterine carcinosarcoma intramedullary metastasis that was refractory to radiotherapy treatment and responded favourably to surgical debulking.

Predictors of Clinical Failure after Endoscopic Lumbar Spine Surgery During the Initial Learning Curve.

OBJECTIVE: This study aims to identify clinical factors that may predict failed endoscopic lumbar spine surgery to guide surgeons with patient selection during the initial learning curve. METHODS: This is an Australasian prospective analysis of the first 105 patients to undergo lumbar endoscopic spine decompression by 3 surgeons. Modified MacNab outcomes, visual analog scale (VAS) and Oswestry Disability Index (ODI) scores were utilized to evaluate clinical outcomes at 6 months postoperatively. Descriptive statistics and ANOVA t tests were performed to measure statistically significant (P < 0.05) associations between variables using GraphPad Prism v10. RESULTS: Patients undergoing endoscopic lumbar surgery via an interlaminar or transforaminal approach have overall good/excellent modified MacNab outcomes and a significant reduction in postoperative VAS and ODI scores. Regardless of the anatomic location of disc herniations, good/excellent modified MacNab outcomes and significant reductions in VAS and ODI were reported post-operatively, however, not in patients with calcified disc herniations. Patients with central and foraminal stenosis overall reported poor/fair modified MacNab outcomes, however, there were significant reductions in VAS and ODI scores postoperatively. Patients with subarticular stenosis or an associated spondylolisthesis reported good/excellent modified MacNab outcomes and significant reductions in VAS and ODI scores postoperatively. Patients with disc herniation and concurrent degenerative stenosis had generally poor/fair modified MacNab outcomes. CONCLUSIONS: The outcomes of endoscopic spine surgery are encouraging with low complication and reoperation rates. However, patients with calcified disc herniations, central canal stenosis, or disc herniation with concurrent degenerative stenosis present challenges during the initial learning curve and may benefit from traditional open or other minimally invasive techniques.

Surgical decompression for malignant cerebral oedema after ischaemic stroke.

BACKGROUND: Large territory middle cerebral artery (MCA) ischaemic strokes account for around 10% of all ischaemic strokes and have a particularly devastating prognosis when associated with malignant oedema. Progressive cerebral oedema starts developing in the first 24 to 48 hours of stroke ictus with an associated rise in intracranial pressure. The rise in intracranial pressure may eventually overwhelm compensatory mechanisms leading to a cascading secondary damage to surrounding unaffected parenchyma. This downward spiral can rapidly progress to death or severe neurological disability. Early decompressive craniectomy to relieve intracranial pressure and associated tissue shift can help ameliorate this secondary damage and improve outcomes. Evidence has been accumulating of the benefit of early surgical decompression in stroke patients. Earlier studies have excluded people above the age of 60 due to associated poor outcomes; however, newer trials have included this patient subgroup. This review follows a Cochrane Review published in 2012. OBJECTIVES: To assess the effectiveness of surgical decompression in people with malignant oedema after ischaemic stroke with regard to reduction in mortality and improved functional outcome. We also aimed to examine the adverse effects of surgical decompression in this patient cohort. SEARCH METHODS: We searched the Cochrane Stroke Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2022, Issue 7 of 12), MEDLINE Ovid, Embase Ovid, Web of Science Core Collection, Scopus databases, ClinicalTrials.gov, and the WHO ICTRP to July 2022. We also reviewed the reference lists of relevant articles. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing decompressive craniectomy with medical management to best medical management alone for people with malignant cerebral oedema after MCA ischaemic stroke. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the search results, assessed study eligibility, performed risk of bias assessment, and extracted the data. The primary outcomes were death and death or severe disability (modified Rankin Scale (mRS) > 4) at 6 to 12 months follow-up. Other outcomes included death or moderate disability (mRS > 3), severe disability (mRS = 5), and adverse events. We assessed the certainty of the evidence using the GRADE approach, categorising it as high, moderate, low, or very low. MAIN RESULTS: We included nine RCTs with a total of 513 participants included in the final analysis. Three studies included patients younger than 60 years of age; two trials accepted patients up to 80 years of age; and one trial only included patients 60 years or older. The majority of included trials (six) mandated a time from stroke ictus to treatment of < 48 hours, whilst in two of them this was < 96 hours. Surgical decompression was associated with a reduction in death (odds ratio (OR) 0.18, 95% confidence interval (CI) 0.12 to 0.27, 9 trials, 513 participants, P < 0.001; high-certainty evidence); death or severe disability (mRS > 4, OR 0.22, 95% CI 0.15 to 0.32, 9 trials, 513 participants, P < 0.001; high-certainty evidence); and death or moderate disability (mRS > 3, OR 0.34, 95% CI 0.22 to 0.52, 9 trials, 513 participants, P < 0.001; moderate-certainty evidence). Subgroup analysis did not reveal any significant effect on treatment outcomes when analysing age (< 60 years versus ≥ 60 years); time from stroke ictus to intervention (< 48 hours versus ≥ 48 hours); or dysphasia. There was a significant subgroup effect of time at follow-up (6 versus 12 months, P = 0.02) on death as well as death or severe disability (mRS > 4); however, the validity of this finding was affected by fewer participant numbers in the six-month follow-up subgroup. There was no consistent reporting of per-participant adverse event rates in any of the included studies, which prevented further analysis. AUTHORS' CONCLUSIONS: Surgical decompression improves outcomes in the management of malignant oedema after acute ischaemic stroke, including a considerable reduction in death or severe disability (mRS > 4) and a reduction in death or moderate disability (mRS > 3). Whilst there is evidence that this positive treatment effect is present in patients > 60 years old, it is important to take into account that these patients have a poorer prospect of functional survival independent of this treatment effect. In interpreting these results it must also be considered that the data demonstrating benefit are drawn from a unique patient subset with profound neurological deficit, reduced level of consciousness, and no pre-morbid disability or severe comorbidity.

Donut sign: a unique radiological sign of cerebral metastasis in malignant mesothelioma.

A man in his 70s presented to the emergency department with a 3-day history of confusion and right-facial droop. He was diagnosed with stage IIIB (T4N2M0) malignant mesothelioma 6 months previously for which he was being given palliative chemotherapy. An MRI of the brain demonstrated a left parietal cerebral metastasis with unique radiological characteristics termed 'donut sign'. He underwent a craniotomy and complete macroscopic resection of the lesion with a good postoperative outcome. Mesothelioma cerebral metastases are a rarely reported clinical entity, with only a handful of case reports and case series available. On MRI they often demonstrate a distinctive thick-walled lesion, termed 'donut sign', that may be indicative of the diagnosis. Furthermore, case autopsy series suggest these metastases may be underdiagnosed in the clinical setting due to the dismal prognosis. With newer and more effective neoplastic treatment strategies emerging, there may be a rising incidence of central nervous system metastases in the future.

Dropped head syndrome in a patient with Parkinson's disease and inflammatory myopathy, treated with sternocleidomastoid release and circumferential cervical fusion.

BACKGROUND: Dropped head syndrome (DHS) is a recently recognised cause of cervical spinal deformity and disability. The combination of Parkinson's disease (PD) and inflammatory myopathy in the genesis of DHS has not been previously reported. Furthermore, the optimal surgical treatment of progressive DHS remains undefined. CASE DESCRIPTION: We report the case of a 64-year-old patient with severe DHS and coronal plane deformity secondary to underlying PD, precipitated by a focal paraspinal myositis, successfully corrected using asymmetric sternocleidomastoid (SCM) release and circumferential cervical fusion. The nuances of decision-making in this challenging patient population are highlighted, including the benefits of intraoperative traction, anterior column reconstruction and bicortical screw fixation. Postoperatively, significant reductions in pain and disability were achieved, along with restoration of cervical lordosis (CL), C2-7 sagittal vertical axis (CSVA) and chin-brow vertical angle (CBVA). CONCLUSIONS: Circumferential cervical fusion with concomitant SCM release is a useful option in the treatment of recalcitrant DHS with biplanar deformity, addressing the unique biomechanical and endocrinological challenges posed by patients with underlying PD.

Conditional Gaussian nonlinear system: A fast preconditioner and a cheap surrogate model for complex nonlinear systems.

Developing suitable approximate models for analyzing and simulating complex nonlinear systems is practically important. This paper aims at exploring the skill of a rich class of nonlinear stochastic models, known as the conditional Gaussian nonlinear system (CGNS), as both a cheap surrogate model and a fast preconditioner for facilitating many computationally challenging tasks. The CGNS preserves the underlying physics to a large extent and can reproduce intermittency, extreme events, and other non-Gaussian features in many complex systems arising from practical applications. Three interrelated topics are studied. First, the closed analytic formulas of solving the conditional statistics provide an efficient and accurate data assimilation scheme. It is shown that the data assimilation skill of a suitable CGNS approximate forecast model outweighs that by applying an ensemble method even to the perfect model with strong nonlinearity, where the latter suffers from filter divergence. Second, the CGNS allows the development of a fast algorithm for simultaneously estimating the parameters and the unobserved variables with uncertainty quantification in the presence of only partial observations. Utilizing an appropriate CGNS as a preconditioner significantly reduces the computational cost in accurately estimating the parameters in the original complex system. Finally, the CGNS advances rapid and statistically accurate algorithms for computing the probability density function and sampling the trajectories of the unobserved state variables. These fast algorithms facilitate the development of an efficient and accurate data-driven method for predicting the linear response of the original system with respect to parameter perturbations based on a suitable CGNS preconditioner.

Safe Electromyography Stimulation Thresholds Within Kambin's Triangle During Endoscopic Transforaminal Lumbar Interbody Fusion.

BACKGROUND: Transforaminal endoscopic approaches through Kambin's triangle traditionally require surgery to be performed without general anesthesia to allow live patient feedback. No reliable intraoperative neuromonitoring method specific to the dorsal root ganglion (DRG), the structure most at risk during this approach, currently exists. OBJECTIVE: To correlate evoked electromyography (EMG) thresholds within Kambin's triangle with new postoperative pain or sensorimotor symptoms potentially resulting from DRG irritation. METHODS: Data were prospectively collected for all patients undergoing endoscopic transforaminal lumbar interbody fusion (TLIF) under general anesthesia at a single institution. A stimulation probe was inserted into Kambin's triangle under fluoroscopic and robotic guidance, before passage of endoscopic instruments. EMG thresholds required to elicit corresponding myotomal responses were measured. Postoperatively, any potential manifestations of DRG irritation were recorded. RESULTS: Twenty-four patients underwent a total of 34 transforaminal lumbar interbody fusion levels during the study period, with symptoms of potential DRG irritation occurring in 5. The incidence of new onset symptoms increased with lower stimulation thresholds. Sensitivities for EMG thresholds of ≤4, ≤8, and ≤11 mA were 0.6, 0.8, and 1, respectively. Corresponding specificities were 0.90, 0.69, and 0.55, respectively. CONCLUSION: We demonstrated for the first time the feasibility of direct intraoperative neuromonitoring within Kambin's triangle in transforaminal endoscopic surgery. Eight milliampere seems to be a reasonable compromise between sensitivity and specificity for this monitoring technique. In the future, larger-scale studies are required to refine safe stimulation thresholds.

BAMCAFE: A Bayesian machine learning advanced forecast ensemble method for complex turbulent systems with partial observations.

Ensemble forecast based on physics-informed models is one of the most widely used forecast algorithms for complex turbulent systems. A major difficulty in such a method is the model error that is ubiquitous in practice. Data-driven machine learning (ML) forecasts can reduce the model error, but they often suffer from partial and noisy observations. In this article, a simple but effective Bayesian machine learning advanced forecast ensemble (BAMCAFE) method is developed, which combines an available imperfect physics-informed model with data assimilation (DA) to facilitate the ML ensemble forecast. In the BAMCAFE framework, a Bayesian ensemble DA is applied to create the training data of the ML model, which reduces the intrinsic error in the imperfect physics-informed model simulations and provides the training data of the unobserved variables. Then a generalized DA is employed for the initialization of the ML ensemble forecast. In addition to forecasting the optimal point-wise value, the BAMCAFE also provides an effective approach of quantifying the forecast uncertainty utilizing a non-Gaussian probability density function that characterizes the intermittency and extreme events. It is shown using a two-layer Lorenz 96 model that the BAMCAFE method can significantly improve the forecasting skill compared to the typical reduced-order imperfect models with bare truncation or stochastic parameterization for both the observed and unobserved large-scale variables. It is also shown via a nonlinear conceptual model that the BAMCAFE leads to a comparable non-Gaussian forecast uncertainty as the perfect model while the associated imperfect physics-informed model suffers from large forecast biases.

Robotic-Assisted Endoscopic Laminotomy: 2-Dimensional Operative Video.

Endoscopy and robotics represent two emerging technologies within the field of spine surgery, the former an ultra-MIS approach minimizing the perioperative footprint and the latter leveraging accuracy and precision. Herein, we present the novel incorporation of robotic assistance into endoscopic laminotomy, applied to a 27-yr-old female with a large caudally migrated L4-5 disc herniation. Patient consent was obtained. Robotic guidance was deployed in (1) planning of a focussed laminotomy map, pivoting on a single skin entry point; (2) percutaneous targeting of the interlaminar window; and (3) execution of precision drilling, controlled for depth. Through this case, we illustrated the potential synergy between these 2 technologies in achieving precise bony removal tailored to the patient's unique pathoanatomy while simultaneously introducing safety mechanisms against human error and improving surgical ergonomics.1,2 The physicians consented to the publication of their images.

Traumatic dorsal spondyloptosis of upper thoracic spine: case report and novel open reduction technique.

Traumatic thoracic spondyloptosis represents a rare but potentially catastrophic spinal injury pattern. We present a unique case of a 37-year-old male who suffered a high-thoracic retroloptosis with resultant complete spinal cord injury following a motor vehicle accident. We describe a novel and effective method of open reduction utilising horizontally oriented temporary rods facilitating controlled, sequential sagittal distraction and unlocking, reversal of anteroposterior shear and restoration of alignment. Using our technique, successful reduction and realignment was achieved.

Syringomyelia in Patient with Concurrent Posttraumatic Hydrocephalus and Tethered Spinal Cord: Implications for Surgical Management.

BACKGROUND: Posttraumatic syringomyelia is a significant source of disability following spinal cord injury (SCI). Despite this, its etiology and optimal treatment remain controversial. Early identification of and intervention at a presyrinx state may halt progression. Here, we present a unique case illustrating the continuum between presyrinx and syrinx in an adult following severe distraction cervical SCI and traumatic brain injury, resulting in both tethered spinal cord and posttraumatic hydrocephalus and subsequent isolated fourth ventricle. The interplay between these etiologic factors and their therapeutic implications are discussed. CASE DESCRIPTION: A 48-year-old female developed rapidly progressive cervical spinal cord edema and hydromyelia almost 6 months after severe SCI and traumatic brain injury, with an initial Glasgow Coma Scale score of 3. Imaging demonstrated both ventral tethering of her cord at the site of injury (C5/6), as well as a trapped fourth ventricle following lateral ventricular shunting for posttraumatic hydrocephalus, with diminished flow of cerebrospinal fluid at the craniocervical junction. Additional shunting of the fourth ventricle led to significant clinical improvement and dramatic radiologic regression of her cord abnormality. CONCLUSIONS: Cognizance of the possible presence of multiple etiologic contributors to posttraumatic syringomyelia and an intricate understanding of their interplay are crucial to the optimal management of this complex pathology.

Proximal Adjacent Segment Disease Manifesting as Retroodontoid Pseudotumor After Fusion to C2.

BACKGROUND: Although adjacent segment disease (ASD) following anterior cervical fusion has been well described in the literature, there is relative paucity of data on this pathology after posterior cervical fusion. To our knowledge, there have been no reported cases of proximal ASD following posterior fusion to C2. CASE DESCRIPTION: We present 2 cases of proximal ASD presenting as retroodontoid pseudotumors following posterior fusion to C2, both in middle-aged females without history of rheumatologic disease. The first occurred in a patient with Klippel-Feil deformity 13 years after C2-6 posterior cervical fusion, the second in a patient 3 and a half years following revisional circumferential C2-T2 fusion. Both were successfully treated with proximal extension of laminectomy and fusion to the occiput, supplemented in the first patient by transdural decompression of retroodontoid mass. CONCLUSIONS: Proximal ASD can manifest as retroodontoid pseudotumor at variable time intervals following posterior fusion to C2. Clinicians must account for this possibility in their decision making.

MicroRNA-212-3p Attenuates Neuropathic Pain via Targeting Sodium Voltage-gated Channel Alpha Subunit 3 (NaV 1.3).

PURPOSE: To explore the role and potential mechanism of miR-212-3p in neuropathic pain regulation. METHODS: Adult male rats were used to establish chronic constriction injury (CCI) model to mimic the neuropathic pain. Then, paw withdrawal threshold (PWT) and paw withdrawal thermal latency (PWL) were determined. The concentrations of interleukin 1 beta (IL-1ß), interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were measured with enzyme-linked immune sorbent assay (ELISA) kit and the expression of miR-212-3p was measured by real time quantitative PCR (RTqPCR). Besides, miR-212-3p agomir was intrathecally injected into CCI rats and the expression of key apoptotic proteins was determined by western blot. Furthermore, dual-luciferase reporter assay was used to determine the binding of miR-212-3p and 3' untranslated regions (3'UTR) of NaV1.3 and the expression levels of NaV1.3 were measured by western blot and RT-qPCR. RESULTS: In the CCI group, the PWT and PWL were significantly decreased and IL-1ß, IL-6 and TNF-α were increased. miR-212-3p was decreased in response to CCI. The intrathecal injection of miR-212-3p agomir into CCI rats improved the PWT and PWL, decreased the IL-1ß, IL-6 and TNF-α, decreased the expression levels of BCL2 associated X, apoptosis regulator (Bax), cleaved caspase-3 and increased the expression levels of BCL2 apoptosis regulator (Bcl-2). The results of dual--luciferase reporter assay showed that miR-212-3p could directly bind with 3'UTR of NaV1.3. The expression of NaV1.3 was up-regulated in CCI rats who were intrathecally injected with miRctrl, whereas it decreased in CCI rats intrathecally injected with miR-212-3p agomir. CONCLUSION: The expression of miR-212a-3p attenuates neuropathic pain by targeting NaV1.3.

Outcome-Based Critical Result Thresholds in the Adult Patient Population.

OBJECTIVES: To derive outcome-based critical result thresholds in the adult patient population. METHODS: We extracted deidentified laboratory results and outcomes (death or discharged) of patients 18 years and older from the Medical Information Mart for Intensive Care database. The lower and upper critical result thresholds were obtained from the nearest minimum and maximum laboratory values, which corresponded to predicted probability of death at 90%. RESULTS: The critical value thresholds were sodium (<123, >153 mmol/L), potassium (<2.2, >6.6 mmol/L), bicarbonate (<15, >49 mmol/L), chloride (<82, >121 mmol/L), urea (>20 mmol/L), creatinine (>1,052 µmol/L), glucose (<1.5, >23.8 mmol/L), total calcium (<1.62, >2.95 mmol/L), magnesium (<0.37, >1.48 mmol/L), phosphate (<0.19, >2.52 mmol/L), pH (<7.22, >7.57), lactate (>5.0 mmol/L), hemoglobin (<4.6 g/dL), WBCs (>32 × 103/µL), prothrombin time (>90 seconds), and international normalized ratio (>10). CONCLUSIONS: The indirect approach described in this study is a pragmatic way to obtain threshold values that are clinically and operationally meaningful.