Spine Instability Neoplastic Score: agreement across different medical and surgical specialties

Traumatic spinal injury patterns of on vs. off-road motorcycle crashes

OBJECTIVE

Two wheel motorized vehicles used in both street transportation and recreation are a common cause of severe injury in the United States (US). To date, there has been limited data describing the spinal injury patterns among these motorcycle injury patients in the US. The goal of this study is to characterize and compare differences in specific injury patterns of patients sustaining traumatic spinal injuries after motocross (off-road) and street bike (on-road) collisions in the southwestern US at a Level I Trauma Center.

METHODS

Trauma registry data was queried for patients sustaining a spinal injury after motorcycle collision from 2010 to 2019 at a single Level I Trauma Center. Computed tomography (CT) scan and magnetic imaging resonance imaging (MRI) reports from initial trauma evaluation were reviewed and data was manually obtained regarding injury morphology and location.

RESULTS

A total of 1798 injuries were identified in 549 patients who sustained a motorcycle collision, specifically 67 off-road and 482 on-road motorcycle patients. Off-road motorcycle patients were found to be significantly younger (34.75 vs. 42.66, p = 0.00015). A total of 46.2% of the off-road injuries were determined to be from compression mechanisms, compared to 32.9% in the on-road cohort (p = 0.0027). The on-road cohort was more likely to have an injury classified as insignificant, such as transverse and spinous process fractures (60.1% vs. 42.5%, p = 00.25). There was no significant difference in regards to junctional, mobile, and semirigid spine segments between the two cohorts.

CONCLUSIONS

Different fracture patterns were seen between the off-road and on-road motorcycle cohorts. Off road motorcyclists experienced significantly more compression and translational injuries, while on road motorcyclists experienced more frequent insignificant injury patterns. Data on the different fracture patterns may help professionals develop safety equipment for motorcyclists.

Critical evaluation of the literature on decision-making in spinal metastases

Decision-making in patients with vertebral metastases is highly complex. Different factors of the patient, their cancer disease and treatment options are involved in it. Treatment schemes and strategies have been modified with the evolution of knowledge and treatment of disseminated oncological disease. This paper analyzes the bibliography that has been used for decision-making in the last three decades, as well as the evolution to the schemes that we could consider contemporary.

Imaging diagnosis of vertebral metastasis

The spine is the third most frequent location for metastatic disease, after the lung and liver. On the other hand, the most frequent bone tumors are metastases and the spine is the main location. A review of the different imaging techniques available, both radiological and nuclear medicine, and the morphological appearance of spinal metastases in each of them is performed. Magnetic resonance imaging is the best imaging modality for detection of spinal metastases. It is important to make the differential diagnosis between vertebral fracture of osteoporotic and pathological cause. Spinal cord compression is a serious complication of metastatic disease and its assessment by imaging through objective scales is decisive for estimating spinal stability and therefore establishing treatment. Lastly, percutaneous intervention techniques are briefly discussed.

[Translated article] Imaging diagnosis of vertebral metastasis

The spine is the third most frequent location for metastatic disease, after the lung and liver. On the other hand, the most frequent bone tumours are metastases and the spine is the main location. A review of the different imaging techniques available, both radiological and nuclear medicine, and the morphological appearance of spinal metastases in each of them is performed. Magnetic resonance imaging is the best imaging modality for detection of spinal metastases. It is important to make the differential diagnosis between vertebral fracture of osteoporotic and pathological cause. Spinal cord compression is a serious complication of metastatic disease and its assessment by imaging through objective scales is decisive for estimating spinal stability and therefore establishing treatment. Lastly, percutaneous intervention techniques are briefly discussed.

[Translated article] Critical evaluation of the literature on decision-making in spinal metastases

Decision-making in patients with vertebral metastases is highly complex. Different factors of the patient, their cancer disease and treatment options are involved in it. Treatment schemes and strategies have been modified with the evolution of knowledge and treatment of disseminated oncological disease. This paper analyzes the bibliography that has been used for decision-making in the last three decades, as well as the evolution to the schemes that we could consider contemporary.

Selection of bone graft type for the surgical treatment of thoracolumbar spinal tuberculosis based on the spinal instability neoplastic score: a retrospective single-center cohort study

OBJECTIVES

This study aimed to establish a standard for selecting bone graft type for thoracolumbar spinal tuberculosis surgery based on the spinal instability neoplastic score (SINS).

METHODS

Patients with thoracolumbar tuberculosis who underwent one-stage debridement posteriorly and instrumentation were divided into a structural bone graft group (SBG) (51 cases) and a non-structural bone graft group (NSBG) (54 cases) according to their SINS. SBG was performed when the SINS was ≥ 13 and NSBG was performed when it was 7 ≤ SINS ≤ 12. Baseline data, clinical outcomes, and imaging outcomes were collected and statistically analyzed between the two groups.

RESULTS

Significant improvements in clinical and imaging outcomes were achieved in both groups. Compared to the SBG group, the operation time of the NSBG group was shorter, the intraoperative blood loss of the NSBG group was less, the bone fusion time of the NSBG group was faster.

CONCLUSION

Non-structural and structural bone grafting can achieve comparable therapeutic effects in patients with spinal tuberculosis, and a suitable selection of bone grafts based on quantitative SINS will make full use of the advantages of different bone grafts.

The Management of Metastatic Spinal Cord Compression in Routine Clinical Practice

(1) Background: Whether clinical management of spinal metastatic disease (SMD) matches evidence-based recommendations is largely unknown. (2) Patients and Methods: A questionnaire was distributed through Spanish Medical Societies, exploring routine practice, interpretation of the SINS and ESCC scores and agreement with items in the Tokuhashi and SINS scales, and NICE guideline recommendations. Questionnaires were completed voluntarily and anonymously, without compensation. (3) Results: Eighty specialists participated in the study. A protocol for patients with SMD existed in 33.7% of the hospitals, a specific multidisciplinary board in 33.7%, 40% of radiological reports included the ESCC score, and a prognostic scoring method was used in 73.7%. While 77.5% of the participants were familiar with SINS, only 60% used it. The different SINS and ESCC scores were interpreted correctly by 57.5-70.0% and 30.0-37.5% of the participants, respectively. Over 70% agreed with the items included in the SINS and Tokuhashi scores and with the recommendations from the NICE guideline. Differences were found across private/public sectors, hospital complexity, number of years of experience, number of patients with SMD seen annually and especially across specialties. (4) Conclusions: Most specialists know and agree with features defining the gold standard treatment for patients with SCC, but many do not apply them.

Review of Hematology-Oncology Emergencies for Internal Medicine Residents

The prevalence of cancer continues to grow globally every year. With therapeutic advances over the recent decades, the prevalence of individuals living with cancer continues to increase. Internal medicine residents can see patients admitted to the hospital for cancer-related emergencies. Early identification and appropriate management of these emergencies have been shown to improve mortality and morbidity. In this article, we aim to review the recent updates in the management of commonly encountered oncologic emergencies in the practice of internal medicine residents. This review will cover spinal cord compression, superior vena cava syndrome, tumor lysis syndrome, hypercalcemia, pericardial tamponade, hypoglycemia, hyponatremia, bowel obstruction, increased intracranial pressure, leukostasis, hyperviscosity syndrome, neutropenic fever, and hypersensitivity reactions.

State-of-the-Art Imaging Techniques in Metastatic Spinal Cord Compression

Metastatic Spinal Cord Compression (MSCC) is a debilitating complication in oncology patients. This narrative review discusses the strengths and limitations of various imaging modalities in diagnosing MSCC, the role of imaging in stereotactic body radiotherapy (SBRT) for MSCC treatment, and recent advances in deep learning (DL) tools for MSCC diagnosis. PubMed and Google Scholar databases were searched using targeted keywords. Studies were reviewed in consensus among the co-authors for their suitability before inclusion. MRI is the gold standard of imaging to diagnose MSCC with reported sensitivity and specificity of 93% and 97% respectively. CT Myelogram appears to have comparable sensitivity and specificity to contrast-enhanced MRI. Conventional CT has a lower diagnostic accuracy than MRI in MSCC diagnosis, but is helpful in emergent situations with limited access to MRI. Metal artifact reduction techniques for MRI and CT are continually being researched for patients with spinal implants. Imaging is crucial for SBRT treatment planning and three-dimensional positional verification of the treatment isocentre prior to SBRT delivery. Structural and functional MRI may be helpful in post-treatment surveillance. DL tools may improve detection of vertebral metastasis and reduce time to MSCC diagnosis. This enables earlier institution of definitive therapy for better outcomes.

Simplified Chinese Version of the Spinal Instability Neoplastic Score in Evaluating Patients with Metastatic Spinal Tumor: A Cross-Cultural Adaptation and Validation

Objective

To translate the original English version of the Spinal Instability Neoplastic Score (SINS) into simplified Chinese, adapt it cross‐culturally, validate its psychometric properties in measuring spinal instability in patients with metastatic spinal tumors in the Chinese mainland, examine the reliability and validity to demonstrate its accuracy and applicability in clinical practice.

Methods

Patients diagnosed with metastatic spinal disease between January 2016 and January 2020 were recruited. The number of participants was advised to be at least 50 for appropriate analysis of reliability, construct validity, as well as ceiling or floor effects, and recruitment of 100 patients was advised for internal consistency analysis. The study was conducted in two phases: first, the SINS was translated into simplified Chinese; second, the factor structure, internal consistency, test–retest reliability, validity, and floor and ceiling effects of the SC‐SINS were assessed. The internationally recognized cross‐cultural adaptation guidelines were followed. Internal consistency was evaluated with Cronbach's alpha. Test–retest reliability was examined among the patients with a 4‐week interval. The validity of the Chinese version of SINS (SC‐SINS) was assessed by examining its relationship with Kostuik classification. Principal component analysis was conducted to confirm the factor structure of each subscale.

Results

A total of 160 participants (88 males and 72 females) were enrolled. No major difficulties occurred in the forward and backward translations of SINS. The internal consistency of SC‐SINS was excellent (Cronbach's α =0.857, ranging from 0.68 to 0.85). Test–retest reliability was also excellent with a value of 0.89, ranging from 0.86 to 0.95. Validity analyses indicated that the SC‐SINS was positively and significantly correlated with Kostuik classification. The correlation between “Posterolateral Involvement of Spinal Elements” and “1‐2 Partial Damage” was the highest with a correlation value of 0.792. The correlation between “Pain” and “1–2 Partial Damage” was the lowest with a value of 0.341. All items showed principal component coefficients greater than 0.4. The values of Factor 1 ranged from 0.523 to 0.681; Factor 2 ranged from 0.591 to 0.731; Factor 3 ranged from 0.613 to 0.754; Factor 4 ranged from 0.461 to 0.711; Factor 5 ranged from 0.513 to 0.701; and Factor 6 ranged from 0.501 to 0.668. In addition, neither floor nor ceiling effects were seen in the SC‐SINS.

Conclusion

The SC‐SINS demonstrated high internal consistency and test–retest reliability, which has been proven valid and reliable to measure spinal stability in patients from the Chinese mainland with metastatic spinal tumor.

Radiographic Features Associated With Increased Surgical Invasiveness in Pyogenic Vertebral Column Osteomyelitis

STUDY DESIGN

Single center retrospective cohort study.

OBJECTIVES

Assess the association between well-known radiographic features for spinal instability from the Spinal Instability in Neoplasia Score (SINS) and surgical invasiveness in treating vertebral column osteomyelitis (VCO). This will potentially help surgeons in surgical planning and aid in developing a pathology specific score.

METHODS

Patients with VCO were identified from hospital coding. On preoperative computed tomography radiographic features, including spinal alignment, vertebral body collapse, location, type of bone lesion, and posterolateral involvement were assessed and scored 0 (stable) to 15 (highly unstable). Surgical invasiveness was graded as 0 = no surgery, 1 = decompression alone, 2 = shortening or posterior stabilization, or 3 = anterior column reconstruction.

RESULTS

A total of 41 patients were included. The mean age of the cohort was 63.3 years (SD 12.0) with male comprising 78%. The mean total radiographic score for the nonsurgical group was 6.39 (3.14) and for the surgical group 10.38 (3.06), P < .001. Spinal alignment, vertebral body collapse, type of bone lesion, and posterolateral involvement correlated with surgical invasiveness (all Ps < .05). Subgroup comparison following analysis of variance showed that only spinal alignment was significantly different between groups 2 and 3.

CONCLUSIONS

Our findings show correlation of the radiographic components of the SINS with surgical invasiveness in management of pyogenic VCO-these findings should aid development of an "instability score" in pyogenic VCO. While most radiographic features assessed correlated with surgical invasiveness spinal alignment appears to be the key feature in determining the need for more invasive surgery.

An analysis of tumor-related potential spinal column instability (Spine Instability Neoplastic Scores 7-12) eventually requiring surgery with a 1-year follow-up

OBJECTIVE

Within the Spine Instability Neoplastic Score (SINS) classification, tumor-related potential spinal instability (SINS 7-12) may not have a clear treatment approach. The authors aimed to examine the proportion of patients in this indeterminate zone who later required surgical stabilization after initial nonoperative management. By studying this patient population, they sought to determine if a clear SINS cutoff existed whereby the spine is potentially unstable due to a lesion and would be more likely to require stabilization.

METHODS

Records from patients treated at the University of California, San Francisco, for metastatic spine disease from 2005 to 2019 were retrospectively reviewed. Seventy-five patients with tumor-related potential spinal instability (SINS 7-12) who were initially treated nonoperatively were included. All patients had at least a 1-year follow-up with complete medical records. A univariate chi-square test and Student t-test were used to compare categorical and continuous outcomes, respectively, between patients who ultimately underwent surgery and those who did not. A backward likelihood multivariate binary logistic regression model was used to investigate the relationship between clinical characteristics and surgical intervention. Recursive partitioning analysis (RPA) and single-variable logistic regression were performed as a function of SINS.

RESULTS

Seventy-five patients with a total of 292 spinal metastatic sites were included in this study; 26 (34.7%) patients underwent surgical intervention, and 49 (65.3%) did not. There was no difference in age, sex, comorbidities, or lesion location between the groups. However, there were more patients with a SINS of 12 in the surgery group (55.2%) than in the no surgery group (44.8%) (p = 0.003). On multivariate analysis, SINS > 11 (OR 8.09, CI 1.96-33.4, p = 0.004) and Karnofsky Performance Scale (KPS) score < 60 (OR 0.94, CI 0.89-0.98, p = 0.008) were associated with an increased risk of surgery. KPS score was not correlated with SINS (p = 0.4). RPA by each spinal lesion identified an optimal cutoff value of SINS > 10, which were associated with an increased risk of surgical intervention. Patients with a surgical intervention had a higher incidence of complications on multivariable analysis (OR 2.96, CI 1.01-8.71, p = 0.048).

CONCLUSIONS

Patients with a mean SINS of 11 or greater may be at increased risk of mechanical instability requiring surgery after initial nonoperative management. RPA showed that patients with a KPS score of 60 or lower and a SINS of greater than 10 had increased surgery rates.

Accuracy and precision of the spinal instability neoplastic score (SINS) for predicting vertebral compression fractures after radiotherapy in spinal metastases: a meta-analysis

Radiotherapy has played an important role in the treatment of spinal metastases. One of the major complications of radiotherapy is vertebral compression fracture (VCF). Although the spinal instability neoplastic score (SINS) was developed for evaluating spinal instability in patients with spinal metastases, it is also commonly used to predict VCF after radiotherapy in patients with spinal metastases. However, its accuracy for predicting radiotherapy-induced VCF and precision remain controversial. The aim of this study was to clarify the diagnostic value of the SINS to predict radiotherapy-induced VCF and to make recommendations for improving its diagnostic power. We searched core databases and identified 246 studies. Fourteen studies were analyzed, including 7 studies (with 1269 segments) for accuracy and 7 studies (with 280 patients) for precision. For accuracy, the area under the summary receiver operating characteristic curve was 0.776. When a SINS cut-off value of 7 was used, as was done in the included studies, the pooled sensitivity was 0.790 and the pooled specificity was 0.546. For precision, the summary estimate of interobserver agreement was the highest dividing 2 categories based on a cut-off value of 7, and the value was 0.788. The body collapse showed moderate relationship and precision with the VCF. The lytic tumor of bone lesion showed high accuracy and fair reliability, while location had excellent reliability, but low accuracy. The SINS system can be used to predict the occurrence of VCF after radiotherapy in spinal metastases with moderate accuracy and substantial reliability. Increasing the cut-off value and revising the domains may improve the diagnostic performance to predict the VCF of the SINS.

Cervical spine multiple myeloma and isolated radiotherapy

Multiple myeloma is a hematologic malignancy frequently presenting with spinal lytic lesions. The authors report the case of a patient with an extensively destructive osteolytic MM lesion in the cervical spine treated exclusively with radiotherapy. Computed tomography and magnetic resonance imaging scans showed an arrest of further progression of instability and resolution of the lytic lesion, showing signs of new bone formation. Whereas surgery should be considered for cases of spinal instability and potential neurological injury, this case demonstrates that isolated radiotherapy can be used in select cases to treat MM lesions and restore the structural integrity of the spinal elements.

Strategy for the Practice of Spine Oncological Surgery During the Covid-19 Pandemic

STUDY DESIGN

Case series.

OBJECTIVE

For each of the most frequent clinical scenarios, the authors reached a consensus on how should be timing and indications be optimized to reduce risk while maintaining the expected outcomes under the Covid-19 pandemics.

SUMMARY OF BACKGROUND DATA

The organization of health care has been changed by the Covid-19 pandemic with a direct impact on Spine Oncology Surgery. Emergency surgery is still a priority, but in case of spinal tumors it should be better defined which conditions require emergency treatment.

METHODS

An expert panel with general spine surgeons, oncological spine surgeons, and radiation oncologists was formed to analyze the most frequent scenarios in spinal musculoskeletal oncology during Covid-19 pandemics.

RESULTS

Spine metastases can be found incidentally during follow-up or can clinically occur by increasing pain, pathologic fracture, and/or neurological symptoms. Primary spine tumors are much more rare and very rarely present with acute onset. The first step is to suspect this rare condition, to avoid to treat a primary tumor as it were a metastasis. Most complex surgery, like en bloc resection, associated with high morbidity and mortality rate for the treatment of low grade malignancy like chordoma or chondrosarcomas, if intensive care unit availability is reduced, can be best delayed some weeks, as not impacting on prognosis, due to the slow growth rate of these conditions. The currently accepted protocols for Ewing sarcoma (ES) and osteogenic sarcoma must be performed for local and systemic disease control. For ES, after the first courses of chemotherapy, radiotherapy can be selected instead of surgery, during Covid-19, to the end of the full course of chemotherapy. In immunocompromised patients, (treated by chemotherapy), it is necessary to avoid contact with affected or exposed people.

CONCLUSION

Even more than during normal times, a multidisciplinary approach is mandatory to share the decision to modify a treatment strategy.

LEVEL OF EVIDENCE

5.

Treatment Strategy for Impending Instability in Spinal Metastases

Backgroud

Determining surgical management of a spinal metastasis is difficult owing to the involvement of multiple factors. The spinal instability neoplastic score (SINS) system is a reliable tool to evaluate instability in spinal metastases. The intermediate SINS (scores 7–12) indicates impending instability, which makes it difficult to determine the proper treatment strategy. In this study, we aimed to compare the initial status and treatment outcomes of a conservative group versus an operative group among patients with spinal metastases with an intermediate SINS of 7–12. Further, we evaluated the time for conversion to surgery in patients who had initially undergone conservative treatment and identified the factors associated with the conversion.

Methods

Among the patients with a spinal metastasis with an intermediate SINS of 7–12 from May 2013 to December 2017, those who were followed up for more than 12 months were enrolled in this study. Patients with signs of a neurologic deficit or cord compression at the initial diagnosis were excluded. Finally, 79 patients (47 in the initially conservative group and 32 in the initially operative group) were enrolled in this study. The performance status, Tomita score, and Tokuhashi score were assessed for group comparison. Components of SINS, the Bilsky grade, and radiosensitivity of tumor were evaluated to determine factors associated with conversion to surgery.

Results

Average follow-up was 20.9 months (range, 12–46 months). The demographic variables, primary cancer type, and performance status were not significantly different between the 2 groups. However, the Tomita score was lower in the initially operative group (p = 0.006). The 1-year treatment outcome assessed based on the change in performance status and vertebral height collapse showed a tendency to deteriorate less in the initially operative group. The rate of conversion to surgery in the initially conservative group was 33% in the first year, after which there was little change in the incidence of conversion. When vertebral body collapse was less than 50% or the tumor was located in the semi-rigid region (T3–T10), the need for conversion to surgery increased statistically significantly (p = 0.039 and p = 0.042, respectively).

Conclusions

The rate of conversion to surgery in initially conservatively treated patients was about 33% in the first year. When a tumor is located in T3–T10 and less than 50% vertebral body collapse is present, surgery may be the better choice than conservative treatment.

Is the Spinal Instability Neoplastic Score Accurate and Reliable in Predicting Vertebral Compression Fractures for Spinal Metastasis? A Systematic Review and Qualitative Analysis

Spinal metastases can present with varying degrees of mechanical instability. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic-related instability while helping to guide referrals among oncology specialists. Some previous papers suggested that the SINS was accurate and reliable, while others disagreed with this opinion. We performed a systematic review regarding the SINS to evaluate its accuracy and precision in predicting vertebral compression fractures (VCFs). The 21 included studies investigated a total of 2118 patients. Thirteen studies dealt with the accuracy of SINS to predict post-radiotherapy VCFs, and eight dealt with the precision. Among 13 studies, 11 agreed that the SINS categories showed statistically significant accuracy in predicting VCF. Among eight studies, body collapse was effective for predicting VCFs in six studies, and alignment and bone lesion in two studies. Location has no statistical significance in predicting VCFs in any of the eight studies. The precision of SINS categories was substantial to excellent in six of eight studies. Among the six components of the SINS, the majority of the included studies reported that location showed near perfect agreement; body collapse, alignment, and posterolateral involvement showed moderate agreement; and bone lesion showed fair agreement. Bone lesion showed significant accuracy in predicting VCFs in half of eight studies, but displayed fair reliability in five of seven studies. Although location was indicated as having near perfect reliability, the component showed no accuracy for predicting VCFs in any of the studies and deleting or modifying the item needs to be considered. The SINS system may be accurate and reliable in predicting the occurrence of post-radiotherapy VCFs for spinal metastasis. Some components seem to be substantially weak and need to be revised.

THE SINS SCALE IN THE EVALUATION OF STABILITY IN PATIENTS WITH SPINAL METASTASIS

ABSTRACT Objective To evaluate the distribution of patients seen in the emergency care unit of the Instituto do Câncer do Estado de São Paulo in the categories “stable”, “indeterminate” and “unstable” as classified by the SINS scale. Methods The medical charts of patients treated between May and September 2013 were reviewed. Patients with a diagnosis of spinal metastasis were analyzed and data on age, sex, primary tumor location, neurological status, and the presence and intensity of pain at rest and in movement were obtained. The SINS criteria were used to evaluate the radiological involvement of the spine. Results We included 81 patients with a mean age of 59.57 years; 32 (39.51%) men and 49 (60.49%) women. Breast (19.75%), prostate (18.52%) and lung (17.28%) were the most common primary tumor sites. Only 18 patients (22.22%) had a single lesion and 51 (62.96%) had 3 or more metastatic lesions. Of the total, 56 (69.14%) were of undetermined stability, 19 were stable (23.46%) and 6 were unstable (7.41%). Twenty-two (27.2%) presented neurological deficit in the physical examination. None of the patients with severe deficit, Frankel A or B, were stable according to the SINS classification. All unstable lesions presented with kyphotic and/or scoliotic deviation (p <0.001). Most patients with undetermined lesions (78.6%) and all patients with unstable lesions had mechanical pain (p = 0.001). Conclusion In this case series, there was a high rate of patients classified by the SINS scale as of undetermined instability (69.14%). There was a high number of patients with multiple metastases (62.96%), which was not considered a modifier of the SINS instability criteria and which needs to be the focus of future studies. Level of evidence IV; Case Series.

Vertebral fractures following stereotactic body radiotherapy for spine metastases

Stereotactic body radiotherapy has emerged as one of the preferred treatments for patients with spine metastases, with the potential for long-term control from lesion irradiation. Post-treatment vertebral compression fractures are a known complication of this therapy, contributing to worsening pain and reduced quality of life, sometimes requiring surgical intervention. This review explores the current knowledge of post-radiotherapy fractures, in terms of the rates and associated predictive factors. A search of databases including Medline, Embase and the Cochrane Library was conducted using keywords such as 'vertebral compression fracture', 'stereotactic body radiotherapy' and 'spine metastases'. The search was limited to published studies up to March 2019, reporting clinical outcomes including both the post-treatment fracture rate and statistical identification of associated risk factors. Rates of post-treatment fractures ranged from 4 to 39%. A variety of factors were found to increase the risk, including the appearance of lytic vertebral disease, degree of pre-existing compression, spinal malalignment, increased dose per fraction and a Spinal Instability Neoplastic Score >6. This knowledge can enable clinicians to counsel patients when considering management options for spine metastases, maintaining the balance between local tumour control and the risk of subsequent fracture.

Metastatic Versus Osteoporotic Vertebral Fractures on MRI: A Blinded, Multicenter, and Multispecialty Observer Agreement Evaluation

BACKGROUND

MRI is assumed to be valid for distinguishing metastatic vertebral fractures (MVFs) from osteoporotic vertebral fractures (OVFs). This study assessed (1) concordance between the image-based diagnosis of MVF versus OVF and the reference (biopsy or follow-up of >6 months), (2) interobserver and intraobserver agreement on key imaging findings and the diagnosis of MVF versus OVF, and (3) whether disclosing a patient's history of cancer leads to variations in diagnosis, concordance, or agreement.

PATIENTS AND METHODS

This retrospective cohort study included clinical data and imaging from 203 patients with confirmed MVF or OVF provided to 25 clinicians (neurosurgeons, radiologists, orthopedic surgeons, and radiation oncologists). From January 2018 through October 2018, the clinicians interpreted images in conditions as close as possible to routine practice. Each specialist assessed data twice, with a minimum 6-week interval, blinded to assessments made by other clinicians and to their own previous assessments. The kappa statistic was used to assess interobserver and intraobserver agreement on key imaging findings, diagnosis (MVF vs OVF), and concordance with the reference. Subgroup analyses were based on clinicians' specialty, years of experience, and complexity of the hospital where they worked.

RESULTS

For diagnosis of MVF versus OVF, interobserver agreement was fair, whereas intraobserver agreement was substantial. Only the latter improved to almost perfect when a patient's history of cancer was disclosed. Interobserver agreement for key imaging findings was fair or moderate, whereas intraobserver agreement on key imaging findings was moderate or substantial. Concordance between the diagnosis of MVF versus OVF and the reference was moderate. Results were similar regardless of clinicians' specialty, experience, and hospital category.

CONCLUSIONS

When MRI is used to distinguish MVF versus OVF, interobserver agreement and concordance with the reference were moderate. These results cast doubt on the reliability of basing such a diagnosis on MRI in routine practice.

Outcomes for Vertebrectomy for Malignancy and Correlation to the Spine Instability Neoplastic Score (SINS): a 10-Year Single-Center Perspective

OBJECTIVE

The clinical prognostic value of the Spinal Instability Neoplastic Score (SINS), in the context of vertebrectomy for neoplasia, has not yet been established. This retrospective study of 134 patients aims to evaluate the efficacy of the SINS to predict outcomes and survival after vertebrectomy for malignancy.

METHODS

The patients were classified into 2 groups: indeterminate stability (SINS 7-12) and unstable (SINS 13-18). Outcomes assessed included survival days after procedure, neurological function (modified Frankel grade), operative time, blood loss, complications, construct failure, and length of inpatient stay.

RESULTS

The indeterminate group included 68 patients, whereas the unstable group included 66 patients. No patients were classified as stable (SINS 0-6). The median survival was 225 days (interquartile range, 81-522 days). There was a statistically significant difference (P < 0.001) in survival days after vertebrectomy between the indeterminate group (435 days) and the unstable group (126 days). The majority of patients (119) had a favourable Frankel grade after procedure with no significant difference between SINS groups (P = 0.534). There were no differences in the operative time (234 vs. 210; P = 0.130), inpatient hospital length of stay (10 days vs. 11 days; P = 0.152), complications, or need for intensive care admission (intensive care unit) between the 2 cohorts. There was a statistically significant difference (P = 0.006) for intraoperative blood loss between the indeterminate group (1400 mL) and the unstable group (850 mL).

CONCLUSIONS

This study demonstrates a statistically significant increased survival in the indeterminate cohort. These results demonstrate the potential ability of the SINS to act as a clinical prognostic tool with regard to survival time.

The clinical utility of the Spinal Instability Neoplastic Score (SINS) system in spinal epidural metastases: a retrospective study

STUDY DESIGN

A retrospective study.

OBJECTIVES

This study assessed the clinical utility of the Spinal Instability Neoplastic Score (SINS) in relation to the surgical treatment of spinal epidural metastasis and factors important for surgical decision-making. These factors include epidural spinal cord compression (ESCC), patient prognosis and neurologic status.

SETTING

Queen Elizabeth II Health Sciences Centre, Halifax, Canada.

METHODS

We identified 285 patients with spinal metastatic disease. Data were extracted through a retrospective review. SINS and ESCC were scored based on CT and MRI, respectively.

RESULTS

Patients were grouped into stable (35%), potentially unstable (52%), and unstable (13%) groups. The overall incidence of metastatic spinal deformity was 9%. Surgical interventions were performed in 21% of patients, including decompression and instrumented fusion (70%), decompression alone (17%), percutaneous vertebral augmentation (9%), and instrumented vertebral augmentation (5%). The use of spinal instrumentation was significantly associated with unstable SINS (p = 0.005). Grade 3 ESCC was also significantly associated with unstable SINS (p < 0.001). Kaplan-Meier analysis revealed that SINS was not a predictor of survival (p = 0.98). In the radiotherapy-alone group, a significant proportion of patients with potentially unstable SINS (30%) progressed into unstable SINS category at an average 364 ± 244 days (p < 0.001).

CONCLUSION

This study demonstrated that more severe categories of SINS were associated with higher degrees of ESCC, and surgical interventions were more often utilized in this group with more frequent placement of spinal instrumentation. Although SINS did not predict patient prognosis, it correlates with the progression of metastatic instability in patients treated with radiotherapy.

Stereotactic body radiation therapy and minimally invasive surgery in the management of spinal metastases: a change in the paradigm

The main goal of treatment in spinal metastatic patients is local control of the disease, pain relief and the maintenance of ambulation. Traditionally, wide surgical resection of the tumour followed by adjuvant radiation and/or chemotherapy has been recommended. Currently, single-fraction or hypofractionated stereotactic body radiation therapy (SBRT) yields a one-year local control rate of over 95% with minimum morbidity, even for tumours previously considered radioresistant. In addition, by posterolateral and circumferential decompression and stabilisation of the spinal cord, it is feasible to create a 2 to 3 mm epidural margin between the dura mater and the tumour (separation surgery), enough to deliver safe and ablative doses of SBRT to the vertebrae. As these patients tend to be frail, such interventions should ideally be minimally invasive, thereby reducing surgical aggressiveness and helping to minimise the delay of any systemic therapies.

Advances in personalized treatment of metastatic spine disease

The spine is one of the most common sites of bony metastases, and its involvement leads to significant patient morbidity. Surgical management in these patients is aimed at improving quality of life and functional status throughout the course of the disease. Resection of metastases often leads to critical size bone defects, presenting a challenge to achieving adequate bone regeneration to fill the void. Current treatment options for repairing these defects are bone grafting and commercial bone cements; however, each has associated limitations. Additionally, tumor recurrence and tumor-induced bone loss make bone regeneration particularly difficult. Systemic therapeutic delivery, such as bisphosphonates, have become standard of care to combat bone loss despite unfavorable systemic side-effects and lack of local efficacy. Developments from tissue engineering have introduced novel materials with osteoinductive and osteoconductive properties which also act as structural support scaffolds for bone regeneration. These new materials can also act as a therapeutic reservoir to sustainably release drugs locally as an alternative to systemic therapy. In this review, we outline recent advancements in tissue engineering and the role of translational research in developing implants that can fully repair bone defects while also delivering local therapeutics to curb tumor recurrence and improve patient quality of life.

Intra- and interobserver reliability of the Spinal Instability Neoplastic Score system for instability in spine metastases: a systematic review and meta-analysis

Mechanical instability is one of the two main indications for surgical intervention in patients with metastatic spine disease. Since its publication in 2010, the Spinal Instability Neoplastic Score (SINS) has been the most commonly used means of assessing mechanical instability. To prove clinically valuable though, diagnostic tests must demonstrate consistency across measures and across observers. Here we report a systematic review and meta-analysis of all prior reports of intraobserver and interobserver reliability of the SINS score. To identify articles, we queried the PubMed, CINAHL, EMBASE, Cochrane, and Web of Science databases for all full-text English articles reporting interobserver or intraobserver reliability for the SINS score, category, or a domain of the SINS score. Articles reporting confidence intervals for these metrics were then subjected to meta-analysis to identify pooled estimates of reliability. Of 167 unique studies identified, seven met inclusion criteria and were subjected to qualitative review and meta-analysis. Intraobserver reliability for SINS score was found to be near perfect [estimate =0.815; 90% CI (0.661-0.969)] and interobserver reliability was substantial [0.673; (0.227-1.12)]. Intraobserver and interobserver reliability among spine surgeons was significantly better than reliability across all observers (both P<0.0001). Qualitative analysis suggested that increased surgeon experience may be associated with greater intraobserver and interobserver reliability among spine surgeons. On the whole, meta-analysis of the available literature suggests SINS to have good intraobserver and interobserver reliability, giving it the potential to be a valuable guide to the management of patients with spinal metastases. Further research is required to demonstrate that SINS score correlates with the clinical decision to stabilize.

The evolution of surgical management for vertebral column tumors

In BriefThere has been a significant shift in treatment paradigms for both primary and metastatic spine tumors over the last several decades. This article highlights some of the more important treatment advances that practitioners should be made aware of. It is important to not only incorporate these changes into individual practice but also appreciate the treatment trends that herald a significantly different future for spine tumor treatment.

Instability and impending instability in patients with vertebral metastatic disease

Metastatic disease commonly involves the spine with an increasing incidence due to a worldwide rise of cancer incidence and a longer survival of patients with osseous metastases. Metastases compromise the mechanical integrity of the vertebra and make it susceptible to fracture. Patients with pathological vertebral fracture often become symptomatic, with mechanical pain generally due to intervertebral instability, and may develop spinal cord compression and neurological deficits. Advances in imaging, radiotherapy, as well as in spinal surgery techniques, have allowed the evolution from conventional palliative external beam radiotherapy to modern stereotactic radiosurgery and from traditional open surgery to less-invasive, and sometimes prophylactic stabilization surgical treatments. It is therefore clear that fracture risk prediction, and maintenance or restoration of intervertebral stability, are important objectives in the management of these patients. Correlation between imaging findings and clinical manifestations is crucial, and a common knowledge base for treatment team members rather than a compartmentalized view is very important. This article reviews the literature on the imaging and clinical diagnosis of intervertebral instability and impending instability in the setting of spine metastatic disease, including the spinal instability neoplastic score, which is a reliable tool for diagnosing unstable or potentially unstable metastatic spinal lesions, and on the different elements considered for treatment.

Prognosis of Single Spinal Metastatic Tumors: Predictive Value of the Spinal Instability Neoplastic Score System for Spinal Adverse Events

STUDY DESIGN

This was a retrospective cohort study.

PURPOSE

We evaluated the predictive value of the Spinal Instability Neoplastic Score (SINS) system for spinal adverse events (SAEs) in patients with single spinal metastatic tumor.

OVERVIEW OF LITERATURE

The SINS system was developed to assess spinal instability in patients with single metastatic spinal tumor. However, the system's potential predictive value for SAEs has been partially studied.

METHODS

This system was applied to a retrospective cohort of 78 patients with single spinal metastatic tumors. The patients underwent surgical treatment and were postoperatively followed up for at least 2 years or until death. The attribution of each score and total SINS to SAE (vertebral compression fracture [VCF] and spinal cord compression [SCC]) occurrence was assessed using the Cox proportional hazards model.

RESULTS

SAEs occurred on average 7 months after diagnosis of spinal metastasis. The mean survival rate post diagnosis was 43 months. Multivariate analysis using the Cox proportional hazards model revealed that the pain (p =0.029) and spinal alignment (p =0.001) scores were significantly related to VCF occurrence, whereas the pain (p =0.008) and posterolateral involvement (p =0.009) scores were related to SCC occurrence.

CONCLUSIONS

Among the components of the SINS system, while pain and spinal alignment showed a significant association with VCF occurrence, pain and posterolateral involvement showed association with SCC occurrence.

Outcomes and Prognosis of Neurological Decompression and Stabilization for Spinal Metastasis: Is Assessment with the Spinal Instability Neoplastic Score Useful for Predicting Surgical Results?

Study Design

Retrospective study.

Purpose

To evaluate the efficacy of the Spinal Instability Neoplastic Score (SINS) in predicting surgical outcomes and survival. Patients were categorized into two groups according to the SINS, and their surgical outcomes and survival following decompression and stabilization were assessed.

Overview of Literature

Palliative surgery in patients with a life expectancy ≥3 months may effectively improve their overall condition in the long term. Currently, the effectiveness of the SINS for predicting surgical results and survival remains controversial.

Methods

This study included 44 patients who underwent decompression and stabilization for spinal metastases at Yokosuka Kyosai Hospital between 2008 and 2017. The patients were divided into two groups: stable (SINS ≤12) and unstable (SINS ≥13). Changes in the Frankel score and Eastern Cooperative Oncology Group Performance Status (ECOG-PS) were compared between the two groups, and patient survival was evaluated according to the SINS, Tokuhashi score, and Katagiri score.

Results

The stable group (SINS range, 7–12) included 24 patients while the unstable group (SINS range, 13–16) included 20 patients. The Frankel score significantly improved from 2.8 to 3.6 in the stable group (p <0.001) and from 2.7 to 3.9 in the unstable group (p <0.001). The ECOG-PS significantly improved from 3.2 to 2.1 in the stable group (p <0.001) and from 3.0 to 1.8 in the unstable group (p <0.001). There was a statistically significant difference in median survival between the two groups.

Conclusions

All patients treated with palliative surgery showed favorable outcomes, as indicated by improved the Frankel score and ECOG-PS following surgery. However, median survival was significantly better in the stable group. The results of this study indicate that the SINS is appropriate for surgical decision making and may be used to predict survival.

The Role of Prognostic Scoring Systems in Assessing Surgical Candidacy for Patients With Vertebral Metastasis: A Narrative Review

STUDY DESIGN

Narrative review.

OBJECTIVES

To review the relevant literature regarding scoring systems for vertebral metastases and quantify their role in contemporary orthopedic practice.

METHODS

A literature search of PubMed, Google Scholar, and Embase was performed on February 7, 2017. Eight scoring systems were selected for detailed review-7 of which were scores focused solely on patient prognosis (Tokuhashi, Tomita, Bauer, Oswestry Spinal Risk Index, Van der Linden, Rades, and Katagiri). The eighth system reviewed was the Spinal Instability Neoplastic Score, which examines for impending spinal instability in patients with vertebral metastases and represents a novel approach compared with hitherto scoring systems.

RESULTS

The Bauer and Oswestry Spinal Risk Index have the most accurate prognostic predictive ability, with the newer Oswestry Spinal Risk Index being favored by the contemporary literature as it demands less investigation and is therefore more readily accessible. There was a growing trend in studies designed to customize scoring systems for individual cancer pathological subtypes. The Spinal Instability Neoplastic Score shows good reliability for predicting instability among surgeons and oncologists.

CONCLUSIONS

The increased understanding of cancer pathology and subsequent development of customized treatments has led to prolonged survival. For patients with vertebral metastases, this affects surgical candidacy not only on the basis of prognosis but also provides prolonged opportunity for the development of spinal instability. Scoring systems have a useful guidance role in these deciding for/against surgical intervention, but in order to remain contemporary ongoing review, development, and revalidation is mandatory.

Management - spinal metastases

Due to a worldwide increase of cancer incidence and a longer life expectancy of patients with metastatic cancer, a rise in the incidence of symptomatic vertebral metastases has been observed. Metastatic spinal disease is one of the most dreaded complications of cancer as it is not only associated with severe pain, but also with paralysis, sensory loss, sexual dysfunction, urinary and fecal incontinency when the neurologic elements are compressed. Rapid diagnosis and treatment have been shown to improve both the quality and length of remaining life. This chapter on vertebral metastases with epidural disease and intramedullary spinal metastases will be discussed in terms of epidemiology, pathophysiology, demographics, clinical presentation, diagnosis, and management. With respect to treatment options, our review will summarize the evolution of conventional palliative radiation to modern stereotactic body radiotherapy for spinal metastases and the surgical evolution from traditional open procedures to minimally invasive spine surgery. Lastly, we will review the most common clinical prediction and decision rules, framework and algorithms, and guidelines that have been developed to guide treatment decision making.

Management of extranodal lymphoma of the spine: a study of 30 patients

Extranodal lymphoma of the spine is often a late manifestation of systemic disease, and may result in symptoms of pain, neurologic compromise or spinal instability. Symptomatic relief is generally achieved by radiotherapy alone, but is not sufficient in addressing spinal instability. The indications for surgery remain controversial, but may be required for spinal stabilization, or refractory disease. Currently, there is a lack of studies that compare the indications and clinical outcomes of patients receiving surgical and nonsurgical management of spinal extranodal lymphoma. Medical records of 30 patients seen from March 2006 to August 2015, with histologically confirmed spinal lymphoma, were retrospectively reviewed. Demographic information, clinical factors, imaging, treatment and clinical outcomes were recorded. 19 patients were treated surgically and 11 nonsurgically (i.e., chemotherapy, radiation or combination). Surgery was performed for emergent neurological deterioration, mechanical stabilization, refractoriness to medical management or to perform an open biopsy for pathological diagnosis. Among those treated surgically, significantly fewer patients could carry on normal activities (KPS <70) at baseline, compared with those treated nonsurgically. However, there were no significant differences regarding pain medication use, functional status at 1 year, or mean survival (87.6 months) between groups. Surgery for extranodal lymphoma may be required in specific cases, resulting in favorable and similar outcomes compared with nonsurgical management.

Surgical management of spinal metastases

INTRODUCTION

Metastatic spinal disease is a source of significant morbidity in patients with cancer. Recent advancements in adjuvant oncologic therapy has led to increased survival for many patients who harbor neoplastic disease. As a result of this, the chance of developing metastatic spinal disease over the course of a cancer patient's lifespan has increased. Symptomatic metastatic spinal disease can cause significant morbidity including severe pain, neurologic deficit, and loss of ambulation. Current treatment of these patients typically involves the use of multiple modalities, including surgery, radiation, and chemotherapy. Areas covered: An extensive literature review was performed to support the author's opinion on the matter of surgical management of spinal metastatic disease. Pubmed was utilized as a primary search engine. Expert commentary: Despite advances in chemotherapy and radiation therapy, surgery remains a mainstay in many of these patients, particularly with those with either significant metastatic spinal epidural compression or spinal instability. This review discusses the surgical management of metastatic spinal disease including a framework for decision making and technical considerations when deciding to operate on these patients.

Classification and scoring systems for metastatic spine tumors: a literature review

Introduction

Accurate evaluation of metastasis and life prognosis is essential for selecting a suitable therapeutic strategy for metastatic spine tumors owing to limitations in treatment options. For this purpose, various classification, evaluation, and scoring systems have been developed.

Methods

Classification, evaluation, and scoring systems for metastatic spine tumors reported to date were identified by performing a literature search on PubMed. We reviewed the most cited classifications and scorings before 2009, and all classifications and scorings reported after 2010 from the search results.

Results

Six classifications and 23 scorings were reviewed. The classification/evaluation methods are divided into 1) anatomical classification/evaluation methods, 2) evaluation methods for neurological symptoms/instability, and 3) scoring systems for predicting life expectancy. The first 2 were useful for the planning and evaluation of surgical indications. Scoring systems for life prognosis also permitted rough prediction of the outcomes and were useful for the selection of a suitable treatment. However, variation of the patient background, diversity of adopted prognostic factors, and the absence of scoring systems that could predict the outcome with an accuracy of 90% or higher introduced some limitations.

Conclusion

The identified classification, evaluation, and scoring systems have been generally useful for treatment strategies. However, we emphasize the necessity of multidisciplinary development and revision of classification and evaluation methods to adapt to the prolongation of survival associated with increased diversity and improvement of treatment options.

Diagnostic algorithm, prognostic factors and surgical treatment of metastatic cancer diseases of the long bones and spine

Oncological management of skeletal metastases has changed dramatically in the last few decades. A significant number of patients survive for many years with their metastases.

Surgeons are more active and the technical repertoire is broader, from plates to intramedullary devices to (tumour) endoprostheses.

The philosophy of treatment should be different in the case of a trauma-related fracture and a pathological fracture. A proper algorithm for establishing a diagnosis and evaluation of prognostic factors helps in planning the surgical intervention.

The aim of palliative surgery is usually to eliminate pain and to allow the patient to regain his/her mobility as well as to improve the quality of life through minimally invasive techniques using life-long durable devices.

In a selected group of patients with an oncologically controlled primary tumour site and a solitary bone metastasis with positive prognostic factors, which meet the criteria for radical excision (approximately 10% to 15% of the cases), a promising three to five years of survival may be achieved, especially in cases of metastases from breast and kidney cancer.

Spinal metastases require meticulous evaluation because decisions on treatment mostly depend on the tumour type, segmental stability, the patient’s symptoms and general state of health.

Advanced radiotherapy combined with minimally invasive surgical techniques (minimally invasive stabilisation and separation surgery) provides durable local control with a low complication rate in a number of patients.

Cite this article: EFORT Open Rev 2017;2:372-381.

The Spinal Instability Neoplastic Score: Impact on Oncologic Decision-Making

STUDY DESIGN

Systematic literature review.

OBJECTIVE

To address the following questions in a systematic literature review: 1. How is spinal neoplastic instability defined or classified in the literature before and after the introduction of the Spinal Instability Neoplastic Score (SINS)? 2. How has SINS affected daily clinical practice? 3. Can SINS be used as a prognostic tool?

SUMMARY OF BACKGROUND DATA

Spinal neoplastic-related instability was defined in 2010 and simultaneously SINS was introduced as a novel tool with criteria agreed upon by expert consensus to assess the degree of spinal stability.

METHODS

PubMed, Embase, and clinical trial databases were searched with the key words "spinal neoplasm," "spinal instability," "spinal instability neoplastic score," and synonyms. Studies describing spinal neoplastic-related instability were eligible for inclusion. Primary outcomes included studies describing and/or defining neoplastic-related instability, SINS, and studies using SINS as a prognostic factor.

RESULTS

The search identified 1414 articles, of which 51 met the inclusion criteria. No precise definition or validated assessment tool was used specific to spinal neoplastic-related instability prior to the introduction of SINS. Since the publication of SINS in 2010, the vast majority of the literature regarding spinal instability has used SINS to assess or describe instability. Twelve studies specifically investigated the prognostic value of SINS in patients who underwent radiotherapy or surgery.

CONCLUSION

No consensus could be determined regarding the definition, assessment, or reporting of neoplastic-related instability before introduction of SINS. Defining spinal neoplastic-related instability and the introduction of SINS have led to improved uniform reporting within the spinal neoplastic literature. Currently, the prognostic value of SINS is controversial.

LEVEL OF EVIDENCE

N/A.