Neurologic Complications of Preoperative Embolization of Spinal Metastasis: A Systemic Review of the Literature Identifying Distinct Mechanisms of Injury

BACKGROUND

Preoperative embolization of spinal metastases may improve outcomes of resection by reducing surgical blood loss and operative time. Neurologic complications are rarely reported and the mechanisms leading to injury are poorly described.

METHODS

We present 2 illustrative cases of embolization-related neurologic injury from distinct mechanisms and the findings of a systemic literature review of similar complications according to the PRISMA guidelines.

RESULTS

A 77-year-old man with a history of renal cell carcinoma presented with gait dyscoordination and arm pain/weakness. Magnetic resonance imaging showed a C7/T1 mass causing severe compression of the C7/T1 roots and spinal cord. After embolization and tumor resection/fusion, lethargy prompted imaging showing multiple posterior circulation infarcts believed to be secondary to reflux of embolic particles. A 75-year-old man with renal cell carcinoma presented with L1 level metastasis causing conus compression and experienced paraplegia after superselective particle embolization presumed to be secondary to flow disruption of the artery of Adamkiewicz. Analysis of the literature yielded 6 articles reporting instances of cranial infarction/ischemia occurring in 10 patients, 12 articles reporting spinal cord ischemia/infarction occurring in 17 patients, and 5 articles reporting symptomatic postembolization tumoral swelling in 5 patients.

CONCLUSIONS

Neurologic injury is a risk of preoperative embolization of spinal metastasis from either compromise of spinal cord vascular supply or cranial stroke from reflux of embolic particles. Postprocedural tumor swelling rarely leads to clinical deficit. Awareness of these complications and the presumed mechanisms of injury may aid clinicians in implementing interventions and in counseling patients before treatment.

Telemedicine During COVID-19 and Beyond: A Practical Guide and Best Practices Multidisciplinary Approach for the Orthopedic and Neurologic Pain Physical Examination

BACKGROUND

The COVID pandemic has impacted almost every aspect of human interaction, causing global changes in financial, health care, and social environments for the foreseeable future. More than 1.3 million of the 4 million cases of COVID-19 confirmed globally as of May 2020 have been identified in the United States, testing the capacity and resilience of our hospitals and health care workers. The impacts of the ongoing pandemic, caused by a novel strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), have far-reaching implications for the future of our health care system and how we deliver routine care to patients. The adoption of social distancing during this pandemic has demonstrated efficacy in controlling the spread of this virus and has been the only proven means of infection control thus far. Social distancing has prompted hospital closures and the reduction of all non-COVID clinical visits, causing widespread financial despair to many outpatient centers. However, the need to treat patients for non-COVID problems remains important despite this pandemic, as care must continue to be delivered to patients despite their ability or desire to report to outpatient centers for their general care. Our national health care system has realized this need and has incentivized providers to adopt distance-based care in the form of telemedicine and video medicine visits. Many institutions have since incorporated these into their practices without financial penalty because of Medicare's 1135 waiver, which currently reimburses telemedicine at the same rate as evaluation and management codes (E/M Codes). Although the financial burden has been alleviated by this policy, the practitioner remains accountable for providing proper assessment with this new modality of health care delivery. This is a challenge for most physicians, so our team of national experts has created a reference guide for musculoskeletal and neurologic examination selection to retrofit into the telemedicine experience.

OBJECTIVES

To describe and illustrate musculoskeletal and neurologic examination techniques that can be used effectively in telemedicine.

STUDY DESIGN

Consensus-based multispecialty guidelines.

SETTING

Tertiary care center.

METHODS

Literature review of the neck, shoulder, elbow, wrist, hand, lumbar, hip, and knee physical examinations were performed. A multidisciplinary team comprised of physical medicine and rehabilitation, orthopedics, rheumatology, neurology, and anesthesia experts evaluated each examination and provided consensus opinion to select the examinations most appropriate for telemedicine evaluation. The team also provided consensus opinion on how to modify some examinations to incorporate into a nonhealth care office setting.

RESULTS

Sixty-nine examinations were selected by the consensus team. Household objects were identified that modified standard and validated examinations, which could facilitate the examinations.The consensus review team did not believe that the modified tests altered the validity of the standardized tests.

LIMITATIONS

Examinations selected are not validated for telemedicine. Qualitative and quantitative analyses were not performed.

CONCLUSIONS

The physical examination is an essential component for sound clinical judgment and patient care planning. The physical examinations described in this manuscript provide a comprehensive framework for the musculoskeletal and neurologic examination, which has been vetted by a committee of national experts for incorporation into the telemedicine evaluation.

Effect of Cage Type on Short-Term Radiographic Outcomes in Transforaminal Lumbar Interbody Fusion

BACKGROUND

The effect of expandable versus static cage type on radiographic outcomes in transforaminal lumbar interbody fusion (TLIF) has not been well studied in the literature. We studied the effect of 3 cage types on change in foraminal height (FH), disk height (DH), subsidence, and segmental lordosis (SL).

METHODS

We conducted a retrospective review of patients who underwent TLIF in a single institution from 2014 to 2019. The following 3 cage types were identified: banana cage, bullet, and expandable cage. Computed tomography (CT) scans of the lumbar spine or lumbar radiographs (when CT scan was not available) with 6-week follow-up time were used for radiographic assessment.

RESULTS

One hundred patients with 133 fused segments were identified. The average age was 60.9 years, and 40% were men. A banana cage was used in 19 segments (14.3%), a bullet cage was used in 47 (35.4%), and an expandable cage was used in 67 segments (50.4%). There were no significant differences in FH (average increase, 0.7 mm; P = 0.771), subsidence (average, 2.3 mm; P = 0.554), DH (average decrease, 1.0 mm; P = 0.769), or clinically significant subsidence (>4 mm; P = 0.174). Expandable cages demonstrated a positive 1.2° gain in SL, whereas both other cages demonstrated a decrease in SL on average (P = 0.05). This result held up on multivariate analysis (P = 0.031).

CONCLUSIONS

The average increase in the foraminal height in TLIF is small (0.7 mm) and is not different between the cage types; therefore, direct decompression is crucially important in this procedure. Although TLIF is often considered to be a kyphotic procedure, an expandable cage demonstrated superiority in terms of segmental lordosis improvement.

Biomechanical evaluation comparing zero-profile devices versus fixed profile systems in a cervical hybrid decompression model: a biomechanical in vitro study

BACKGROUND CONTEXT

The use of zero-profile devices and the need for posterior fixation in conjunction with a cervical hybrid decompression model have yet to be investigated.

PURPOSE

To compare the biomechanics of zero-profile and fixed profile cervical hybrid constructs composed of anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF). Fixed profile devices included anterior plating, whereas zero-profile devices included integrated screws.

STUDY DESIGN

In vitro cadaveric biomechanical study.

METHODS

Twelve fresh-frozen cadaveric spines (C2-C7) were divided into two groups of equal bone mineral density, fixed profile versus zero profile (n=6). Groups were instrumented from C3-C6 with either (1) an expandable ACCF device and a static ACDF spacer with an anterior plate (Hybrid-AP) or (2) a zero-profile ACCF spacer with adjacent zero-profile ACDF spacer (Hybrid-Z). Motion was captured for the (1) intact condition, (2) a hybrid model with lateral mass screws (LMS), (3) a hybrid model without LMS, and (4) a hybrid model without LMS following simulated repetitive loading (fatigue).

RESULTS

Hybrid-AP with LMS reduced motion in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) by 77%, 88%, and 82%, respectively, compared with intact. Likewise, Hybrid-Z with LMS exhibited the greatest reduction in motion relative to intact in FE, LB, and AR by 90%, 95%, and 66%, respectively. Following simulated in vivo fatiguing, an increase in motion was observed for both groups in all planes, particularly during Hybrid-Z postfatigue condition where motion increased relative to intact by 29%. Overall, biomechanical equivalency was observed between Hybrid-AP and Hybrid-Z groups (p>.05). Three (50%) of the Hybrid-Z group specimens exhibited signs of implant migration from the inferior endplate during testing.

CONCLUSIONS

Fixed profile systems using an anterior plate for supplemental fixation is biomechanically more favorable to maintain stability and prevent dislodgement. Dislodgement of 50% of the Hybrid-Z group without LMS emphasizes the necessity for posterior fixation in a zero-profile cervical hybrid decompression model.

Spinal cord ischemia/infarct after cauda equina syndrome from disc herniation - A case study and literature review

Background

Spinal cord infarction is rare and occurs in 12/100,000; it represents 0.3%-2% of central nervous system infarcts. Here, we present a patient who developed recurrent bilateral lower extremity paraplegia secondary to spinal cord infarction 1 day after a successful L4-5 microdiscectomy in a patient who originally presented with a cauda equina syndrome.

Case Description

A 56-year-old patient presented with an acute cauda equina syndrome characterized by severe lower back pain, a right foot drop, saddle anesthesia, and acute urinary retention. When the lumbar magnetic resonance imaging (MRI) revealed a large right paracentral lumbar disc herniation at the L4-L5 level, the patient underwent an emergency minimally invasive right-sided L4-5 discectomy. Immediately, postoperatively, the patient regained normal function. However, 1 day later, while having a bowel movement, he immediately developed the recurrent paraplegia. The new lumbar MRI revealed acute ischemia and an infarct involving the distal conus medullaris. Further, workup was negative for a spinal cord vascular malformation, thus leaving an inflammatory postsurgical vasculitis as the primary etiology of delayed the conus medullaris infarction.

Conclusions

Acute neurologic deterioration after spinal surgery which does not neurologically correlate with the operative level or procedure performed should prompt the performance of follow-up MR studies of the neuraxis to rule out other etiologies, including vascular lesions versus infarctions, as causes of new neurological deficits.

Perioperative Complications and Mortality Following Anterior Odontoid Screw Fixation in Elderly Patients: A National Database Analysis

OBJECTIVE

To identify predictors of short-term mortality and complications after anterior odontoid screw fixation.

METHODS

This was a retrospective analysis of a national database. The American College of Surgeons National Quality Improvement Database was queried using Current Procedural Terminology codes to identify patients aged ≥60 years who underwent surgery for anterior fixation of odontoid fracture admitted from 2007 to 2016. Univariate analysis and subsequent multivariate analysis were used to analyze risk factors for postoperative complications and 30-day postoperative mortality. Complications were defined as surgical-site infection, wound breakdown, pneumonia, venous thromboembolism, stroke, myocardial infarction, sepsis, renal progressive renal insufficiency/acute kidney injury, or cardiac arrest.

RESULTS

A total of 198 patients were identified. Mean age was 77.7 (±8.7) years and 60.6% were female. Overall mortality rate was 7.6%, and the complication rate was 9.1%. In multivariate analysis, dependent functional status (0.012; odds ratio [OR] 5.2; 95% confidence interval [CI] 1.42-18.72) and preoperative systemic inflammatory response syndrome (P = 0.011; OR 6.2; 95% CI 1.52-25.79) predicted mortality. Emergency case status (P = 0.033; OR 3.4; 95% CI 1.10-10.70) predicted perioperative complications. Age was not significantly associated with either complications or mortality in multivariate analysis.

CONCLUSIONS

Functional dependence and preoperative systemic inflammatory response syndrome predict mortality following odontoid screw placement. Although age often is considered a limiting factor in pursuing surgical intervention in patients with odontoid fracture, age did not independently increase odds of either complications or perioperative mortality in this analysis. Further studies are needed to explore these findings.

Multifocal Epidural Neurosarcoidosis Causing Spinal Cord Compression: A Case Report

We describe a rare case of multifocal extramedullary epidural neurosarcoidosis that presented with myelopathy without motor deficits and perform a literature review for previous cases of epidural neurosarcoidosis. A 46-year-old woman presented with lower back pain, urinary incontinence, gait disturbance, and sensory loss without motor deficits. Spine magnetic resonance imaging (MRI) showed multiple epidural lesions, the largest causing spinal cord compression at the T5 level. A computed tomography (CT)-guided biopsy of the dominant lesion showed noncaseating granulomas consistent with neurosarcoidosis. She was treated with a course of dexamethasone and discharged home after a 10-day hospital course. She was discharged home on oral prednisone taper over a four-month period. At her latest follow-up, she is neurologically intact and gainfully employed. This case demonstrates that certain cases of epidural neurosarcoidosis causing spinal cord compression may be treated with medical therapy alone in the absence of severe neurological deficits.

Incidence and Predictors of Hardware Failure After Instrumentation for Spine Metastasis: A Single-Institutional Series

OBJECTIVE

We report a retrospective analysis of hardware failure in patients requiring instrumentation for spinal metastasis.

METHODS

In a retrospective study at a single institution, we identified 58 patients who underwent spinal instrumentation for metastasis from 2012 to 2018. Hardware failure was defined as screw pullout/loosening, cage migration, progressive kyphosis, or an otherwise-noticeable instrumentation deficit detectable on imaging. Risk factors for hardware failure with a P < 0.05 in in univariate were included in multivariate logistic regression models controlled for age, sex, and previously identified risk factors for hardware failure.

RESULTS

In total, 58 patients required instrumentation for metastatic spine disease. Median age was 60.2 years (interquartile range 49.0-66.3), 38 patients (65.5%) were male, and median follow-up was 8.1 months (interquartile range 3.1-20.7). Eight patients (13.8%) developed signs of hardware failure during follow-up, of whom 2 patients (3.4%) underwent operative revision. In univariate analysis, Eastern Cooperative Oncology Group performance status >2 (P = 0.049) and multiple myeloma lesions (P = 0.010) were significant predictors of failure. Both factors maintained significance in a multivariate logistic regression model controlled for age, sex, history of spine radiation, and number of fused levels with P = 0.047; odds ratio 12.7 (95% confidence interval 1.03-156.4) for Eastern Cooperative Oncology Group performance status over 2 and P = 0.012; odds ratio 31.5 (95% confidence interval 2.2-460.0) for multiple myeloma lesions.

CONCLUSIONS

The rate of hardware failure in this cohort was 13.8%, although operative revision rate was 3.4%. Spinal instrumentation in patients with poor preoperative functional status or multiple myeloma may be more likely to develop instrumentation failure.

The Effect of Cigarette Smoking on Wound Complications After Single-Level Posterolateral and Interbody Fusion for Spondylolisthesis

OBJECTIVE

To evaluate the impact of cigarette smoking on the development of wound complications, including wound dehiscence, superficial infection, deep infection, or organ space infection, within the first 30 postoperative days in patients undergoing surgery for spondylolisthesis.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database for the years 2012-2014 was used to identify adult patients who underwent single-level posterolateral fusion (PLF) or interbody fusion for spondylolisthesis. Wound complications occurring within 30 days were compared between current smokers and nonsmokers.

RESULTS

A total of 1688 patients who underwent single-level PLF or interbody fusion for spondylolisthesis were identified, among whom 271 were current smokers (16.1%). The overall wound complication rate was 3.3% for smokers versus 1.8% for nonsmokers (P = 0.095). When stratified by operative technique, the rate of wound complications was not significantly different between smokers and nonsmokers undergoing PLF (2.4% vs. 2.6%; P = 1.00); however, smokers who underwent interbody fusion were more likely to experience a wound complication compared with nonsmokers undergoing interbody fusion (3.7% vs. 1.3%; P = 0.028). On multivariate analysis, smoking was an independent predictor of organ/space infection irrespective of fusion technique used (odds ratio, 15.4; 95% confidence interval, 1.34-175.4; P = 0.028).

CONCLUSIONS

The rate of wound complications was not higher in smokers undergoing PLF alone, but was significantly higher in smokers who underwent interbody fusion. However, multivariate analysis identified smoking as an independent predictor of organ/space infection irrespective of fusion technique used.

Use of Bone Morphogenetic Protein-2 in Vertebral Column Tumor Surgery: A National Investigation

OBJECTIVE

To report the rate of bone morphogenetic protein-2 (BMP-2) use in vertebral column tumor surgery.

METHODS

The Nationwide Inpatient Sample database (2012-2014) was queried to identify patients who underwent spinal fusion for vertebral column tumors (primary benign, primary malignant, or metastatic). The rate of BMP-2 use was calculated, and patient and operative factors associated with its use were also investigated.

RESULTS

We identified 9375 patients who underwent fusion surgery for spinal tumors between 2012 and 2014, with 540 cases using BMP-2 (5.8%). Preoperative diagnosis revealed that the rate of BMP-2 use in primary benign tumor surgery was 4.9%, 7.6% for primary malignant tumors, and 5.7% for metastatic lesions (P = 0.607). The overall complication rate was 13.2% (13.4% in the NO-BMP-2 group vs. 11.1% in the BMP-2 group; P = 0.504). Patients who received this growth factor were less likely to have epidural spinal cord compression at presentation (37.0% vs. 49.2%; P = 0.014), and more likely to have elective surgery (53.7% vs. 37.7%; P < 0.001). Analysis of hospital location indicated that the highest use of BMP-2 was in the South (7.4% rate; P = 0.002). There was no statistical difference between age, sex, insurance status, comorbidities, the presence of a pathologic fracture, or the use of inpatient radiotherapy or chemotherapy between patients who received BMP-2 and controls.

CONCLUSIONS

BMP-2 has been used off-label to promote arthrodesis; however, its use in patients with spinal tumors is controversial. In this national study, BMP-2 use was highest in the South, in patients without epidural cord compression at presentation, and in elective cases.

Predicting critical care unit-level complications after long-segment fusion procedures for adult spinal deformity

Background

To identify predictive factors for critical care unit-level complications (CCU complication) after long-segment fusion procedures for adult spinal deformity (ASD).

Methods

The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database [2010-2014] was reviewed. Only adult patients who underwent fusion of 7 or more spinal levels for ASD were included. CCU complications included intraoperative arrest/infarction, ventilation >48 hours, pulmonary embolism, renal failure requiring dialysis, cardiac arrest, myocardial infarction, unplanned intubation, septic shock, stroke, coma, or new neurological deficit. A stepwise multivariate regression was used to identify independent predictors of CCU complications.

Results

Among 826 patients, the rate of CCU complications was 6.4%. On multivariate regression analysis, dependent functional status (P=0.004), combined approach (P=0.023), age (P=0.044), diabetes (P=0.048), and surgery for over 8 hours (P=0.080) were significantly associated with complication development. A simple scoring system was developed to predict complications with 0 points for patients aged <50, 1 point for patients between 50-70, 2 points for patients 70 or over, 1 point for diabetes, 2 points dependent functional status, 1 point for combined approach, and 1 point for surgery over 8 hours. The rate of CCU complications was 0.7%, 3.2%, 9.0%, and 12.6% for patients with 0, 1, 2, and 3+ points, respectively (P<0.001).

Conclusions

The findings in this study suggest that older patients, patients with diabetes, patients who depend on others for activities of daily living, and patients who undergo combined approaches or surgery for over 8 hours may be at a significantly increased risk of developing a CCU-level complication after ASD surgery.

Minimally invasive transpedicular approach for the treatment of central calcified thoracic disc disease: a technical note

PURPOSE

To assess the utility of stereotactic navigation for the surgical treatment of ossified, paracentral thoracic discs via a minimally invasive (MI) transpedicular approach.

METHODS

The authors performed a retrospective review of cases with paracentral thoracic disc herniation resulting in myelopathy where a traditional MI approach would be difficult, who underwent a stereotactic assisted MI transpedicular approach via a tubular retractor system between 2011 and 2016. Five cases of patients over the age of 18 were selected. Collected data included patient age at surgery, sex, preoperative Nurick grade, number of levels treated, calcified disc presence, length of surgery, estimated blood loss (EBL), length of stay (LOS), complication rate, postoperative Nurick grade, and length of follow-up.

RESULTS

Five patients had a stereotaxic assisted MI transpedicular thoracic discectomy for paracentrally located calcified disc herniation. Intraoperative navigational images were acquired using intraoperative CT scans (O-arm) to plan and guide the surgical procedure, and real-time navigation was used for precise navigation around the cord to access and remove all fragments. MIS surgery was successfully performed in these otherwise contraindicated cases due to the use of intraoperative real-time stereotactic navigation. All patients had a successful decompression around the anterior aspect of the cord.

CONCLUSION

The traditional MI transpedicular thoracic discectomy approach can be further refined and enhanced by stereotactic navigation to expand the limitations of the MIS technique allowing for an increased number and types of patients eligible for minimally invasive surgery. Therefore, MIS via a tubular retractor system with stereotactic navigation is a novel, safe, and effective improvement in feasibility from the traditional minimally invasive transpedicular thoracic discectomy technique.

Effect of body mass index on surgical outcomes after posterior spinal fusion for adolescent idiopathic scoliosis

OBJECTIVE

Obesity is an increasing public health concern in the pediatric population. The purpose of this investigation was to examine the impact of body mass index (BMI) on 30-day outcomes after posterior spinal fusion for adolescent idiopathic scoliosis (AIS).

METHODS

The American College of Surgeons National Surgical Quality Improvement Program Pediatric database (2013 and 2014) was reviewed. Patients 10–18 years of age who had undergone fusion of 7 or more spinal levels for AIS were included. Thirty-day outcomes (complications, readmissions, and reoperations) were compared based on patient BMI per age- and sex-adjusted growth charts as follows: normal weight (NW; BMI < 85th percentile), overweight (OW; BMI 85th–95th percentile), and obese (OB; BMI > 95th percentile).

RESULTS

Patients eligible for study numbered 2712 (80.1% female and 19.9% male) and had a mean age of 14.4 ± 1.8 years. Average BMI for the entire cohort was 21.9 ± 5.0 kg/m2; 2010 patients (74.1%) were classified as NW, 345 (12.7%) as OW, and 357 (13.2%) as OB. The overall complication rate was 1.3% (36/2712). For NW and OW patients, the complication rate was 0.9% in each group; for OB patients, the rate was 4.2% (p < 0.001). The 30-day readmission rate was 2.0% (55/2712) for all patients, 1.6% for NW patients, 1.2% for OW patients, and 5.0% for OB patients (p < 0.001). The 30-day reoperation rate was 1.4% (39/2712). Based on BMI, this reoperation rate corresponded to 0.9%, 1.2%, and 4.8% for NW, OW, and OB patients, respectively (p < 0.001). After controlling for patient age, number of spinal levels fused, and operative/anesthesia time on multiple logistic regression analysis, obesity remained a significant risk factor for complications (OR 4.61), readmissions (OR 3.16), and reoperations (OR 5.33; all p < 0.001).

CONCLUSIONS

Body mass index may be significantly associated with short-term outcomes after long-segment fusion procedures for AIS. Although NW and OW patients may have similar 30-day outcomes, OB patients had significantly higher wound complication, readmission, and reoperation rates and longer hospital stays than the NW patients. The findings of this study may help spine surgeons and patients in terms of preoperative risk stratification and perioperative expectations.

Minimally Invasive Separation Surgery with Intraoperative Stereotactic Guidance: A Feasibility Study

BACKGROUND

The treatment of spinal metastasis consists of algorithms combining surgical and radiation modalities. Recently the concept of separation surgery followed by stereotactic radiosurgery was shown to be a safe and effective treatment to achieve local tumor control.

OBJECTIVE

We examined a minimally invasive approach to separation surgery in a cadaveric study followed by a patient cohort with spinal metastasis using navigation to discuss our results and provide a technical note.

METHODS

A cadaveric study using minimally invasive access systems examined the feasibility of spinal cord decompression. Subsequently, 17 patients with spinal metastasis underwent minimally invasive separation surgery and instrumentation using navigation. All patients were at least 3/5 and pre- and post-operative CT scans were used to evaluate the decompression. Endpoints included neurologic function, operative time, estimated blood loss, duration of hospital stay, and complications.

RESULTS

The cadaveric study demonstrated adequate decompression of the spinal cord. For the operative cases, the post-operative imaging demonstrated excellent separation for safe stereotactic radiosurgery. The mean incision length was 4.9 cm. The average operative time was 6 hours and 48 minutes, the mean length of stay was 12.8 days and the mean surgical blood loss was 458 mL. The median Spine Instability Neoplastic Score score was 10 with a range of 6-16. All patients remained or improved their neurologic baseline with excellent pain control. One patient incurred a perioperative complication.

CONCLUSIONS

Minimally invasive separation surgery for spinal metastasis allows for circumferential decompression of the spinal cord and safe post-operative stereotactic radiosurgery. In addition, we demonstrated the efficacy of intra-operative navigation in guiding the resection.

Impact of body mass index on 30-day outcomes after spinopelvic fixation surgery

Background:

Obesity is one of the most prevalent chronic diseases associated with degenerative spinal disease. There is limited evidence regarding the short-term outcome of patients with elevated BMI following spinopelvic fixation surgery.

Methods:

We used the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database from 2013 to 2014. Inclusion criteria included: adults, aged 18 and older, who underwent all-cause spinopelvic fixation surgery. Primary outcome measures were 30-day readmission, reoperation, and major complication rates. Logistic regression analysis was used to assess the effect of elevated body mass index (BMI) on 30-day outcome.

Results:

A total of 618 patients met inclusion criteria stratified into levels of BMI: 11.2% were Class 2 obese and 10.3% were Class 3 obese. Significant differences were found between the classes for the incidence of revision surgery, reoperations, and deep wound infections. However, there were no significant increases in readmissions and major complications rates, and only Class 3 obese patients had significantly higher odds of reoperation than those who were not obese.

Conclusion:

Significant differences between all classes of obesity regarding revision surgery, reoperation, and deep wound infection rates were found. Class 3 obese patients had significantly higher odds of reoperation, most likely attributed to the greater number/severity of preoperative comorbidities.

Glioblastoma multiforme presenting with an open ring pattern of enhancement on MR imaging

Background:

Intracerebral ring enhancing lesions can be the presentation of a variety of pathologies, including neoplasia, inflammation, and autoimmune demyelination. Use of a precise diagnostic algorithm is imperative in correctly treating these lesions and minimizing potential adverse treatment effects.

Case Description:

A 55-year-old patient presented to the hospital with complaints of a post-concussive syndrome and a non-focal neurologic exam. Imaging revealed a lesion with an open ring enhancement pattern, minimal surrounding vasogenic edema, and minimal mass effect. Given the minimal mass effect, small size of the lesion, and nonfocal neurological exam, we elected to pursue a comprehensive noninvasive neurologic workup because our differential ranged from inflammatory/infectious to neoplasm. Over the next 8 weeks, the patient's condition worsened, and repeat imaging showed marked enlargement of the lesion with a now closed ring pattern of enhancement with satellite lesions and a magnetic resonance (MR) spectroscopy and perfusion signature suggestive of neoplasm. The patient was taken to surgery for biopsy and debulking of the lesion. Surgical neuropathology examination revealed glioblastoma multiforme.

Conclusion:

The unique open ring enhancement pattern of this lesion on initial imaging is highly specific for a demyelinating process, however, high-grade glial neoplasms can also present with complex and irregular ring enhancement including an open ring sign. Therefore, other imaging modalities should be used, and close follow-up is warranted when the open ring sign is encountered.

Thirty-day readmission and reoperation rates after single-level anterior cervical discectomy and fusion versus those after cervical disc replacement

OBJECTIVE The goal of this study was to compare 30-day readmission and reoperation rates after single-level anterior cervical discectomy and fusion (ACDF) versus those after cervical disc replacement (CDR). METHODS The authors used the 2013-2014 American College of Surgeons National Surgical Quality Improvement Program database. Included were adult patients who underwent first-time single-level ACDF or CDR for cervical spondylosis or disc herniation. Primary outcome measures were readmission and/or reoperation within 30 days of the original surgery. Logistic regression analysis was used to assess the independent effect of the procedure (ACDF or CDR) on outcome, and results are presented as odds ratios with 95% confidence intervals. RESULTS A total of 6077 patients met the inclusion criteria; 5590 (92.0%) patients underwent single-level ACDF, and 487 (8.0%) patients underwent CDR. The readmission rates were 2.6% for ACDF and 0.4% for CDR (p = 0.003). When stratified according to age groups, only patients between the ages of 41 and 60 years who underwent ACDF had a significantly higher readmission rate than those who underwent CDR (2.5% vs 0.7%, respectively; p = 0.028). After controlling for patient age, sex, body mass index, smoking status, history of chronic obstructive pulmonary disease (COPD), diabetes, hypertension, steroid use, and American Society of Anesthesiologists (ASA) class, patients who underwent CDR were significantly less likely to undergo readmission within 30 days than patients who underwent ACDF (OR 0.23 [95% CI 0.06-0.95]; p = 0.041). Patients with a history of COPD (OR 1.97 [95% CI 1.08-3.57]; p = 0.026) or hypertension (OR 1.62 [95% CI 1.10-2.38]; p = 0.013) and those at ASA Class IV (OR 14.6 [95% CI 1.69-125.75]; p = 0.015) were significantly more likely to require readmission within 30 days. The reoperation rates were 1.2% for ACDF and 0.4% for CDR (p = 0.086), and multivariate analysis revealed that CDR was not associated with lower odds of reoperation (OR 0.60 [95% CI 0.14-2.55]; p = 0.492). However, increasing age was associated with a higher risk (OR 1.02 [95% CI 1.00-1.05]; p = 0.031) of reoperation; a 2% increase in risk per year of age was found. CONCLUSIONS Patients who underwent single-level ACDF had a higher readmission rate than those who underwent single-level CDR in this study. When stratified according to age, this effect was seen only in the 41- to 60-year age group. No significant difference in the 30-day single-level ACDF and single-level CDR reoperation rates was found. Although patients in the ACDF group were older and sicker, other unmeasured covariates might have accounted for the increased rate of readmission in this group, and further investigation is encouraged.

Radiographic Pearls in the Evaluation of an Extradural Thoracic Meningioma: A Case Report

Spinal meningiomas are the most common of adult spinal tumors. Spinal meningiomas account for up to 45% of all intradural spinal tumors in adults and up to 25% of all spinal tumors. While spinal meningiomas are traditionally classified as intradural lesions, up to 14% may have an extradural component. Preoperative evaluation and directed use of imaging techniques are key in these rare but observed cases, to accurately diagnose and direct therapy. In this report, the authors present a case of a 61-year-old female with an incidentally found, exclusively extradural thoracic meningioma treated with surgical resection, highlighting key radiographic pearls in the evaluation of these uncommon lesions.

Isolated synchondrosis fracture of the atlas presenting as rotatory fixation of the neck: Case report and review of literature

Background:

Exclusive to the pediatric population, cartilaginous fractures of the atlas are singularly rare. Rarer still are those fractures that produce a fixed, rotational deficit of the neck. Here, the authors present the case of a 4-year-old boy with an isolated fracture of the anterior synchondrosis of C1 with a rotational component following a fall, as well as a review of the literature. Management with serial bedside manipulation, which is unique to our report, helped conservatively correct the rotation of the patient's neck, and, coupled with rigid bracing, demonstrated a comprehensive management strategy that resulted in fracture ossification at 3 months.

Case Description:

Our patient is a 4-year-old boy who fell from a bunk bed and complained of severe neck pain. The patient was brought to the emergency room and was found to have an isolated anterior fracture of the right frontal synchondrosis of the atlas. After conservative management with a hard collar and cautious manual reductions at the bedside, rotation of our patient's neck spontaneously resolved on day 3. After 3 months of rigid immobilization, the patient remained at neurological baseline and his fracture was healed. Literature review demonstrated age range between 2 and 6 years, with a subset of patients demonstrating rotational components to their fractures. Complete resolution of nearly all patients treated with rigid immobilization after fracture was documented, yet several patients experienced delayed diagnosis.

Conclusions:

Knowledge of the radiographic appearance of the C1 ossification centers as well as the normal timeline and sequence of ossification is essential in differentiating a true synchondrosis fracture from normal, nonossified cervical cartilage. With early diagnosis, immobilization, pain control, and muscle relaxants, patients can recover well with conservative management, can successfully ossify fracture sites, and can recover without sequelae.

Ultra-delayed lumbar surgical wound hematoma

Background:

There exists an inherent risk of increased venous thromboembolism (VTE) in surgical spine patients, which is independent of their existing risk factors. Prophylaxis and treatment of VTE is an imprecise practice and may have serious complications even well after the initial surgery. Furthermore, there are no clear guidelines on how to manage postoperative spine patients with regards to the timing of anticoagulation.

Case Description:

Here, we present the case of a middle-aged male, status post L2/3 laminectomy and discectomy who developed bilateral below the knee deep venous thrombosis. He was started on Enoxaparin and transitioned to Warfarin and returned with axial back pain, and was found to have a postoperative hematoma almost 3 weeks later in a delayed fashion.

Conclusion:

Delayed surgical wound hematoma with neural compression is an important complication to identify and should remain high on the differential diagnosis in patients on warfarin who present with axial spinal pain.

Postoperative urinary retention in patients undergoing elective spinal surgery

OBJECTIVE

Postoperative urinary retention (POUR) is a common problem leading to morbidity and an increased hospital stay. There are limited data regarding its baseline incidence in patients undergoing spinal surgery and the risk factors with which it may be associated. The purpose of this study was to evaluate the incidence of POUR in elective spine surgery patients and determine the factors associated with its occurrence.

METHODS

The authors retrospectively reviewed the records of patients who had undergone elective spine surgery and had been prospectively monitored for POUR during an 18-month period. Collected data included operative positioning, surgery duration, volume of intraoperative fluid, length of hospital stay, and patient characteristics such as age, sex, and medical comorbidities. Dialysis patients or those with complete urinary retention preoperatively were excluded from analysis.

RESULTS

Of the 397 patients meeting the study inclusion criteria, 35 (8.8%) developed POUR. An increased incidence of POUR was noted in those who underwent posterior lumbar surgery, those with benign prostatic hypertrophy (BPH), those with chronic constipation or prior urinary retention, and those using a patient-controlled analgesia pump postoperatively. An increased incidence of POUR was seen with a longer operative time but not with intraoperative intravenous fluid administration. A significant relationship between the female sex and POUR was noted after controlling for BPH, yet there was no association between POUR and diabetes or intraoperative instrumentation. Postoperative retention significantly prolonged the hospital stay. Three patients developed epidural hematomas necessitating operative reexploration, and while they experienced POUR, they also developed the full constellation of cauda equina syndrome.

CONCLUSIONS

Awareness of the risk factors for POUR may be useful in perioperative Foley catheter management and in identifying patients who need particular vigilance when they are due to void postprocedure. A greater understanding of POUR may also prevent longer hospital stays in select at-risk patients. Postoperative retention is rarely caused by a postoperative cauda equina syndrome due to epidural hematoma, which is also associated with saddle anesthesia, leg pain, and weakness, yet the delineation of isolated POUR from this urgent complication is necessary for optimal patient care.

The Impact of Hospital Teaching Status on Timing of Intervention, Inpatient Morbidity, and Mortality After Surgery for Vertebral Column Fractures with Spinal Cord Injury

OBJECTIVE

To investigate the impact of hospital teaching status on the timing of intervention and inpatient morbidity and mortality after surgery for acute spinal cord injury (SCI).

METHODS

Data from the Nationwide Inpatient Sample (2002-2011) were reviewed. Patients were included if they had a diagnosis of closed vertebral column fracture with SCI, underwent spine surgery, and were admitted urgently or emergently. Early intervention (the day of or the day after admission), inpatient morbidity and mortality rates were compared between patients admitted to teaching versus nonteaching hospitals. Multivariable regression analyses were performed.

RESULTS

A total of 9236 patients were identified (mean age 43 years, 82.6% male gender), with 78.7% admitted to a teaching hospital (n = 7,272) and 21.3% to a nonteaching hospital (n = 1,964). The most common mechanism of injury was a motor vehicle collision (43.9%), while the most common fracture location was between C5 and C7 (35.3%), and 22% of cases were complete SCIs. Following multivariable analysis, teaching hospital status was significantly associated with early intervention (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.01-1.25), but not with complication development (OR, 1.09; 95% CI, 0.98-1.23) or mortality (OR, 1.19; 95% CI, 0.91-1.56).

CONCLUSIONS

In this nationwide study, patients with vertebral column fractures with SCI who were admitted to teaching hospitals were more likely to receive early intervention compared to patients admitted to nonteaching hospitals. Future studies into the long-term implications of admission to teaching hospitals versus nonteaching hospitals for patients with SCI are encouraged.

Postoperative urinary retention in patients undergoing elective spinal surgery

OBJECTIVE Postoperative urinary retention (POUR) is a common problem leading to morbidity and an increased hospital stay. There are limited data regarding its baseline incidence in patients undergoing spinal surgery and the risk factors with which it may be associated. The purpose of this study was to evaluate the incidence of POUR in elective spine surgery patients and determine the factors associated with its occurrence. METHODS The authors retrospectively reviewed the records of patients who had undergone elective spine surgery and had been prospectively monitored for POUR during an 18-month period. Collected data included operative positioning, surgery duration, volume of intraoperative fluid, length of hospital stay, and patient characteristics such as age, sex, and medical comorbidities. Dialysis patients or those with complete urinary retention preoperatively were excluded from analysis. RESULTS Of the 397 patients meeting the study inclusion criteria, 35 (8.8%) developed POUR. An increased incidence of POUR was noted in those who underwent posterior lumbar surgery, those with benign prostatic hypertrophy (BPH), those with chronic constipation or prior urinary retention, and those using a patient-controlled analgesia pump postoperatively. An increased incidence of POUR was seen with a longer operative time but not with intraoperative intravenous fluid administration. A significant relationship between the female sex and POUR was noted after controlling for BPH, yet there was no association between POUR and diabetes or intraoperative instrumentation. Postoperative retention significantly prolonged the hospital stay. Three patients developed epidural hematomas necessitating operative reexploration, and while they experienced POUR, they also developed the full constellation of cauda equina syndrome. CONCLUSIONS Awareness of the risk factors for POUR may be useful in perioperative Foley catheter management and in identifying patients who need particular vigilance when they are due to void postprocedure. A greater understanding of POUR may also prevent longer hospital stays in select at-risk patients. Postoperative retention is rarely caused by a postoperative cauda equina syndrome due to epidural hematoma, which is also associated with saddle anesthesia, leg pain, and weakness, yet the delineation of isolated POUR from this urgent complication is necessary for optimal patient care.

Predictive parameters for the antecedent development of hip pathology associated with long segment fusions to the pelvis for the treatment of adult spinal deformity

BACKGROUND

The surgical treatment of adult scoliosis frequently involves long segment fusions across the lumbosacral joints that redistribute tremendous amounts of force to the remaining mobile spinal segments as well as to the pelvis and hip joints. Whether or not these forces increase the risk of femoral bone pathology remains unknown. The aim of this study is to determine the correlation between long segment spinal fusions to the pelvis and the antecedent development of degenerative hip pathologies as well as what predictive patient characteristics, if any, correlate with their development.

METHODS

A retrospective chart review of all long segment fusions to the pelvis for adult degenerative deformity operated on by the senior author at the Duke Spine Center from February 2008 to March 2014 was undertaken. Enrolment criteria included all available demographic, surgical, and clinical outcome data as well as pre and postoperative hip pathology assessment. All patients had prospectively collected outcome measures and a minimum 2-year follow-up. Multivariable logistic regression analysis was performed comparing the incidence of preoperative hip pain and antecedent postoperative hip pain as a function of age, gender, body mass index (BMI), and number of spinal levels fused.

RESULTS

In total, 194 patients were enrolled in this study. Of those, 116 patients (60%) reported no hip pain prior to surgery. Eighty-three patients (71.6%) remained hip pain free, whereas 33 patients (28.5%) developed new postoperative hip pain. Age, gender, and BMI were not significant among those who went on to develop hip pain postoperatively (P < 0.0651, 0.3491, and 0.1021, respectively). Of the 78 patients with preoperative hip pain, 20 patients (25.6%) continued to have hip pain postoperatively, whereas 58 patients reported improvement in the hip pain after long segment fusion for correction of their deformity, a 74.4% rate of reduction. Age, gender, and BMI were not significant among those who continued to have hip pain postoperatively (P < 0.4386, 0.4637, and 0.2545, respectively). Number of levels fused was not a significant factor in the development of hip pain in either patient population; patients without preoperative pain who developed pain postoperatively (P < 0.1407) as well as patients with preoperative pain who continued to have pain postoperatively (P < 0.0772).

CONCLUSION

This study demonstrates that long segment lumbosacral fusions are not associated with an increase in postoperative hip pathology. Age, gender, BMI, and levels fused do not correlate with the development of postoperative hip pain. The restoration of spinal alignment with long segment fusions may actually decrease the risk of developing femoral bone pathology and have a protective effect on the hip.