Pre- and intraoperative thoracic spine localization techniques: a systematic review.

OBJECTIVE: In the era of modern medicine with an armamentarium full of state-of-the art technologies at our disposal, the incidence of wrong-level spinal surgery remains problematic. In particular, the thoracic spine presents a challenge for accurate localization due partly to body habitus, anatomical variations, and radiographic artifact from the ribs and scapula. The present review aims to assess and describe thoracic spine localization techniques. METHODS: The authors performed a literature search using the PubMed database from 1990 to 2020, compliant with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A total of 27 articles were included in this qualitative review. RESULTS: A number of pre- and intraoperative strategies have been devised and employed to facilitate correct-level localization. Some of the more well-described approaches include fiducial metallic markers (screw or gold), metallic coils, polymethylmethacrylate, methylene blue, marking wire, use of intraoperative neuronavigation, intraoperative localization techniques (including using a needle, temperature probe, fluoroscopy, MRI, and ultrasonography), and skin marking. CONCLUSIONS: While a number of techniques exist to accurately localize lesions in the thoracic spine, each has its advantages and disadvantages. Ultimately, the localization technique deployed by the spine surgeon will be patient-specific but often based on surgeon preference.

Survival, fusion, and hardware failure after surgery for spinal metastatic disease.

OBJECTIVE: Decompression with instrumented fusion is commonly employed for spinal metastatic disease. Arthrodesis is typically sought despite limited knowledge of fusion outcomes, high procedural morbidity, and poor prognosis. This study aimed to describe survival, fusion, and hardware failure after decompression and fusion for spinal metastatic disease. METHODS: The authors retrospectively examined a prospectively collected, single-institution database of adult patients undergoing decompression and instrumented fusion for spinal metastases. Patients were followed clinically until death or loss to follow-up. Fusion was assessed using CT when performed for oncological surveillance at 6-month intervals through 24 months postoperatively. Estimated cumulative incidences for fusion and hardware failure accounted for the competing risk of death. Potential risk factors were analyzed with univariate Fine and Gray proportional subdistribution hazard models. RESULTS: One hundred sixty-four patients were identified. The mean age ± SD was 62.2 ± 10.8 years, 61.6% of patients were male, 98.8% received allograft and/or autograft, and 89.6% received postoperative radiotherapy. The Kaplan-Meier estimate of median survival was 11.0 months (IQR 3.5-37.8 months). The estimated cumulative incidences of any fusion and of complete fusion were 28.8% (95% CI 21.3%-36.7%) and 8.2% (95% CI 4.1%-13.9%). Of patients surviving 6 and 12 months, complete fusion was observed in 12.5% and 16.1%, respectively. The estimated cumulative incidence of hardware failure was 4.2% (95% CI 1.5-9.3%). Increasing age predicted hardware failure (HR 1.2, p = 0.003). CONCLUSIONS: Low rates of complete fusion and hardware failure were observed due to the high competing risk of death. Further prospective, case-control studies incorporating nonfusion instrumentation techniques may be warranted.

The impact of age on approach-related complications with navigated lateral lumbar interbody fusion.

OBJECTIVE: Age is known to be a risk factor for increased complications due to surgery. However, elderly patients can gain significant quality-of-life benefits from surgery. Lateral lumbar interbody fusion (LLIF) is a minimally invasive procedure that is commonly used to treat degenerative spine disease. Recently, 3D navigation has been applied to LLIF. The purpose of this study was to determine whether there is an increased complication risk in the elderly with navigated LLIF. METHODS: Patients who underwent 3D-navigated LLIF for degenerative disease from 2014 to 2019 were included in the analysis. Patients were divided into elderly and nonelderly groups, with those 65 years and older categorized as elderly. Ninety-day medical and surgical complications were recorded. Patient and surgical characteristics were compared between groups, and multivariate regression analysis was used to determine independent risk factors for complication. RESULTS: Of the 115 patients included, 56 were elderly and 59 were nonelderly. There were 15 complications (25.4%) in the nonelderly group and 10 (17.9%) in the elderly group, which was not significantly different (p = 0.44). On multivariable analysis, age was not a risk factor for complication (p = 0.52). However, multiple-level LLIF was associated with an increased risk of approach-related complication (OR 3.58, p = 0.02). CONCLUSIONS: Elderly patients do not appear to experience higher rates of approach-related complications compared with nonelderly patients undergoing 3D navigated LLIF. Rather, multilevel surgery is a predictor for approach-related complication.

Robotic-Assisted Spinal Surgery: Current Generation Instrumentation and New Applications.

In contrast to other surgical fields, robotics is relatively new to spinal surgery. The initial focus for spinal robotics has been on accurate pedicle screw placement, which early studies have shown to be successful. Beyond pedicle screw placement, however, newer generation spinal robots have the capability of navigation, which can impact other aspects of a spinal procedure. In this study, pedicle screw placement with the recently introduced Excelsius GPS robot (Globus) was similarly found to be accurate in a cohort of patients undergoing both open and minimally invasive fusion. Potential applications of the spinal robot's navigation capability are demonstrated.

Spinal dural arteriovenous fistula formation after scoliosis surgery: case report.

Spinal dural arteriovenous fistulas are diagnostically challenging lesions, and they are not well described in patients with a history of a spinal deformity correction. The authors present the challenging case of a 74-year-old woman who had previously undergone correction of a spinal deformity with subsequent revision. Several years after the last deformity operation, she developed a progressive myelopathy with urinary incontinence over a 6-month period. After evaluation at the authors' institution, an angiogram was obtained, demonstrating a fistula at the T12-L1 region. Surgical ligation of the fistula was performed with subsequent improvement of the neurological symptoms. This case is thought to represent the first fistula documented in an area of the spine that had previously been operated on, and to the authors' knowledge, it is the first case report to be associated with spinal deformity surgery. A brief historical overview and review of the pathophysiology of spinal dural arteriovenous fistulas is also included.

Analysis of Outcomes Between Traditional Open versus Mini-Open Approach in Surgical Treatment of Spinal Metastasis.

OBJECTIVE: The treatment of spinal metastasis carries significant surgical morbidity, and decompression and stabilization are often necessary. Less invasive techniques may reduce risks and postoperative pain. This study describes the differences between a mini-open (MO) procedure and a traditional open surgery (OS) for symptomatic spinal metastasis, and reports differences in outcome for similar patients undergoing each procedure. METHODS: We describe a MO technique and retrospective analysis of 20 OS patients who were matched to 20 MO patients by histology, spinal region, and levels instrumented. MO surgery combined a traditional midline exposure for tumor resection with transfascial pedicle screw fixation. Outcome measures included estimated blood loss (EBL), operative time (OT), length of stay (LOS), transfusion rate, complication rate, ASIA Impairment Scale motor score (AMS), and pain scores. Statistical analysis used unpaired t tests and Fisher exact test. RESULTS: Average age of the patients was 58.3 years. Forty-eight percent of patients were women. Average number of levels treated was 5.9. Both groups had similar LOS (P = 0.98), OT (P = 0.30), perioperative complication rates (P = 0.51), transfusion rates (P = 0.33), and AMS (P = 0.17). EBL was found to be significantly lower in the MO group than the open group (805 ± 138 mL vs. 1732 ± 359 mL, respectively; P = 0.019). The MO group had a significant reduction in postoperative pain (-1.71 ± 0.5 vs. 0.33 ± 0.7, P = 0.018). CONCLUSIONS: Although further studies are needed, the MO approach appears to result in decreased blood loss and postoperative pain, without compromising neural element decompression or spinal stability. These findings are consistent with the use of muscle sparing, minimally invasive pedicle screw fixation.

Lumbar Arthroplasty Core Herniation Presenting With Cauda Equina Syndrome: Case Report of a Rare Complication.

BACKGROUND: Treatment failures of artificial disc implantation are well-described, but posterior herniation of the arthroplasty core is rare. We present a case of posterior herniation of the arthroplasty core resulting in cauda equina syndrome in a 36-yr-old woman. Preoperative imaging studies including computed tomography (CT), magnetic resonance imaging (MRI), and CT Myelogram were performed; only the CT Myelogram demonstrated the severe compression well. This report highlights the radiographic findings on multiple imaging modalities, clinical implications, and management considerations of posterior arthroplasty failures. OBJECTIVE: To demonstrate a rare complication of lumbar arthroplasties. The biomechanical considerations, surgical management, and thorough radiographic work-up demonstrate successful diagnosis and treatment of this unusual complication. METHODS: The patient's chart was reviewed for medical history, laboratory and radiographic studies, and outpatient clinical follow-up. RESULTS: After imaging work-up, this patient was found to have a herniation of the arthroplasty core at L5-S1. She was taken emergently to the operating room for a decompression at L5-S1 and arthroplasty core removal. She made some recovery neurological, but over 3 mo time, she developed a spondylolisthesis with new back pain and radiculopathy. This ultimately responded well to an L5-S1 instrumented posterior fusion. CONCLUSION: Posterior herniation of the lumbar arthroplasty core is a rare complication from implantation of an artificial lumbar disc. Confirmation of the diagnosis is best confirmed with a CT Myelogram. Furthermore, this case underscores the biomechanical importance of the artificial disc given the development of the spondylolisthesis after removal, and fusion after arthroplasty core removal should be considered.

Neurosurgical Management of Sacral Tumors: Review of the Literature and Operative Nuances.

BACKGROUND: Sacral tumors present a significant challenge to the spine surgeon. As new techniques have evolved in recent years, these lesions have become more amenable to aggressive surgical treatment. Although sacral tumors make up only a small minority of spinal tumors, their surgical management warrants special consideration. METHODS: Based on our experience, we highlight 3 important surgical nuances specifically for the treatment of sacral tumors: preservation and maximization of neurologic function, protection of ventral abdominal and pelvic structures, and lumbopelvic fixation. RESULTS: Two cases of patients with sacral tumors treated at our institution are presented to illustrate these points. Both patients had successful postoperative courses, and remained pain free, well-fixated, and neurologically intact at 3-4 month follow-up. They had no evidence of biomechanical instability. CONCLUSIONS: To ensure a successful outcome, a goal-directed, methodical approach is required.

Resource utilization and indications for helicopter transport of head-injured children.

INTRODUCTION: Helicopter emergency medical services (HEMS) have provided benefit for severely injured patients. However, HEMS are likely overused for the transportation of both adult and pediatric trauma patients. In this study, we aim to evaluate the degree of overuse of helicopter as a mode of transport for head-injured children. In addition, we propose criteria that can be used to determine if a particular patient is suitable for air versus ground transport. MATERIALS AND METHODS: We identified patients who were transported to our facility for head injuries. We included only those patients who were transported from another facility and who were seen by the neurosurgical service. We recorded a number of data points including age, gender, race, Glasgow Coma Score (GCS), and intubation status. We also collected data on a number of imaging findings such as mass effect, edema, intracranial hemorrhage, and skull fractures. Patients undergoing emergent nonneurosurgical intervention were excluded. RESULTS: Of the 373 patients meeting inclusion criteria, 116 (31.1%) underwent a neurosurgical procedure or died and were deemed appropriate for helicopter transport. The remaining 68.9% of patients survived their injuries without neurosurgical intervention and were deemed nonappropriate for helicopter transport. Multivariable logistic regression identified GCS 3-8 and/or presence of mass effect, edema, epidural hematoma (EDH), and open-depressed skull fracture as appropriate indications for helicopter transport. CONCLUSIONS: The majority of patients transported to our facility by helicopter survived their head injury without need for neurosurgical intervention. Only those patients meeting clinical (GCS 3-8) or radiographic (mass effect, edema, EDH, open-depressed skull fracture) criteria should be transported by air. LEVEL OF EVIDENCE: Level III (Diagnostic Study).

Congenital Agenesis of the C6 Pedicle Leading to Misdiagnosis of a Traumatically Jumped Facet: A Case Report.

This case report discusses the rare issue of an atrophic cervical pedicle at the C6 level in a patient found unconscious with a jumped facet and an unknown mechanism of injury. A means to discern between traumatic jumped facets versus congenital anomalies is addressed, including missing pedicles, which is encountered at the C6 level in this case. A literature review revealed that the most common level where this occurs is at the C6 level. The structural anatomic pathologies and the variants relative to congenital facet atrophy are identified, including the location and the surrounding vasculature; more specifically, the vertebral arteries. This information is helpful to assist clinicians when discerning between a traumatic subluxation injury that requires instrumentation and reduction versus a congenital anomaly that can usually be managed conservatively.

Delayed Presentation of Cerebral Air Embolism from a Left Atrial-Esophageal Fistula: A Case Report and Review of the Literature.

Air embolism developing from an atrial-esophageal fistula that was created as a complication from an atrial ablation procedure is a rare, yet usually fatal diagnosis. Neurologic manifestations such as meningitis, altered mental status, seizures, strokes, transient ischemic attacks (TIAs), psychiatric changes, and coma can ensue. Imaging of the brain might reveal infarcts, cerebral edema, as well as signs of pneumocephalus. This case describes a 42-year-old male with recent cardiac ablation procedure at an outside hospital for refractory atrial fibrillation (A-fib) who presented with altered mental status, dyspnea and diaphoresis. His initial head computed tomography (CT) scan revealed pneumocephalus. He was started on a heparin drip for a non-ST elevation myocardial infarction (NSTEMI), but developed severe coagulopathy. The patient's mental status quickly deteriorated. Given recent cardiac ablation procedure, the cause of his air embolism was thought to be from a created left atrial-esophageal fistula. Despite medical management, he was too unstable to undergo any surgical intervention for his atrial-esophageal fistula or to transfer to a hyperbaric oxygen therapy center, and expired on the second day following his hospital admission. To our knowledge, few reports have been published in the literature describing delayed cerebral air embolism from an atrial-esophageal fistula. Prompt diagnosis, hyperbaric oxygen therapy, and surgical intervention are essential to avoid mortality in these patients. This article aims to increase awareness of such a rare, but significant complication.

Safety and cost effectiveness of early discharge following microscopic trans-sphenoidal resection of pituitary lesions.

BACKGROUND: Inpatient hospitalization following trans-sphenoidal resection of a pituitary neoplasm has traditionally involved a hospital stay of 2 days or more. It has been the policy of the senior pituitary neurosurgeon (GSA) since February 2008 to allow discharge home on postoperative day (POD) 1 if thirst mechanism is intact and the patient is tolerating oral hydration. The goal of this study was to evaluate the safety and cost-effectiveness of this practice. METHODS: We reviewed the charts of 30 patients, designated the early discharge group, who consecutively underwent microscopic trans-sphenoidal resection from February 2008 to December 2009. We then reviewed the charts of 30 patients, designated the standard discharge group, who consecutively underwent trans-sphenoidal resection from May 2007 to February 2008 before discharge home on POD1 was considered an appropriate option. Safety and cost-effectiveness of the two patient groups were retrospectively evaluated. RESULTS: Patients in the early discharge group went home, on average, on POD 1.3. Following exclusion of two outliers, the average date of discharge of patients in the standard discharge group was POD 2.2. The policy of early discharge saved an average of $1,949 per patient-approximately 4% the total cost of the procedure. Trends toward decreased costs did not reach statistical significance. While no patient suffered any measurable morbidity as a result of early discharge home, 1 in 3 patients in the early discharge group required unscheduled postoperative re-evaluation-a figure significantly higher than the standard discharge group. CONCLUSIONS: At a dedicated pituitary center with the resources to closely monitor outpatient endocrinological and postsurgical issues, early discharge home following trans-sphenoidal surgery is a safe option that is associated with an increase in the number of unscheduled postoperative visits and a trend toward lower costs.