Metastatic Spine Tumor Surgery: A Comparative Study of Minimally Invasive Approach Using Percutaneous Pedicle Screws Fixation Versus Open Approach

A new era in the management of spinal metastasis

Despite the recent advances in cancer treatment, the incidence of patients with spinal metastases continues to grow along with the total number of cancer patients. Spinal metastases can significantly impair activities of daily living (ADL) and quality of life (QOL), compared with other types of bone metastases, as they are characterized with severe pain and paralysis caused by skeletal-related events. Reduced ADL can also lead to treatment limitations as certain anticancer agents and radiation therapy are not compatible treatments; thus, leading to a shorter life expectancy. Consequently, maintaining ADLs in patients with spinal metastases is paramount, and spine surgeons have an integral role to play in this regard. However, neurosurgeon, orthopedic and spinal surgeons in Japan do not have a proactive treatment approach to spinal metastases, which may prevent them from providing appropriate treatment when needed (clinical inertia). To overcome such endemic inertia, it is essential for 1) spine surgeons to understand and be more actively involved with patients with musculoskeletal disorders (cancer locomo) and cancer patients; 2) the adoption of a multidisciplinary approach (coordination and meetings not only with the attending oncologist but also with spine surgeons, radiologists, rehabilitation specialists, and other professionals) to preemptive treatment such as medication, radiotherapy, and surgical treatment; and 3) the integration of the latest findings associated with minimally invasive spinal treatments that have expanded the indications for treatment of spinal metastases and improved treatment outcomes. This heralds a new era in the management of spinal metastases.

The Impact of Preoperative Adaptive Training on Postoperative Outcomes in Lumbar Spine Fusion Surgery for Lumbar Disc Herniation: A Retrospective Analysis

Purpose

Lumbar disc herniation, often treated with surgical decompression when conservative measures fail, presents challenges due to prolonged prone positioning in surgeries. This retrospective study evaluates the benefits of preoperative adaptive training to mitigate post-surgical physiological changes.

Patients and Methods

A review of medical records from June 2021 to March 2023 identified 170 patients unresponsive to conservative treatments. Grouped into adaptive training and control groups based on historical data, the former had undergone exercises to prepare for surgery and postoperative changes. Vital signs and VAS scores were extracted from patient records to assess training impact.

Results

The adaptive training group demonstrated stabilized vital signs intraoperatively, with a notable improvement in surgical exposure compared to the control group. However, there were no significant differences in operative time or blood loss between the groups. Additionally, postoperative VAS scores showed no significant improvement in the adaptive training group at follow-up intervals of 14 days, 1 month, and 3 months post-operation, compared to the control group.

Conclusion

Our study reveals that preoperative adaptive training stabilizes intraoperative blood pressure fluctuations in lumbar disc herniation surgeries. However, this stabilization does not significantly impact long-term postoperative pain management. This highlights the need for further research to explore comprehensive strategies that effectively combine preoperative training with postoperative care.

Safety and feasibility of ultra-long construct navigated minimally invasive spine surgery with adjuvant radiotherapy in extensive spinal metastasis : a comparative analysis

BACKGROUND

Our study compares the outcomes of extensive spinal metastasis patients treated with Ultra-Long Construct Navigated Minimally Invasive Spine Surgery (UNMISS) with Adjuvant Radiotherapy to those receiving only radiotherapy. Spinal metastasis often necessitates interventions like radiotherapy, chemotherapy, or surgery, with an increasing trend towards surgical management. minimally invasive spine surgery has demonstrated advantages over traditional open surgery, with fewer complications and better postoperative outcomes. Radiotherapy continues as a standard for those unsuitable for surgery.

METHODS

This retrospective study included extensive spinal metastasis patients treated between January 2017 and December 2020. We compared patients undergoing UNMISS in conjunction with radiotherapy to patients receiving radiotherapy alone, evaluating demographic data, disease characteristics, and treatment outcomes (VAS, survival) to establish statistical significance.

RESULTS

Twenty-three patients were included in our study. Fourteen patients underwent UNMISS, and nine patients received radiotherapy alone. There was no difference in baseline characteristics of patients. The longest construct in our case series involved T1 to iliac. Both cohorts showed significant improvement in pain scores post-treatment (p = 0.01). However, the UNMISS group demonstrated significantly lower post-treatment VAS scores (p = 0.003), indicating enhanced pain relief. Survival outcomes did not differ significantly between the two groups.

CONCLUSION

The UNMISS should be considered as an alternative treatment in a patient with symptomatic extensive spinal metastasis. The primary goal of this technique is to stabilize the multiple levels of spinal metastasis and decompression of the neural element if needed. This technique is safe and has a better outcome in pain improvement than the patient who received radiotherapy alone.

[Translated article] The role of minimally invasive spine surgery in the treatment of vertebral metastasis (Part 1): A clinical review

Spinal metastases represent a significant burden on the quality of life in patients affected by active oncological disease due to the high incidence of pain syndromes, spinal deformity, and neurological impairment. Surgery plays a decisive role in improving quality of life by controlling pain, restoring neurological function and maintaining spinal stability, as well as contributing to the response to medical therapy. Minimally invasive surgery (MIS) is a treatment option in certain patients with high surgical risk since it has a low rate of complications, intraoperative bleeding, hospital stay, and offers similar results to open surgery. In this review, we present the role of MIS in this pathology and some cases treated in our hospital.

The role of minimally invasive spine surgery in the treatment of vertebral metastasis (part 1): A clinical review

Spinal metastases represent a significant burden on the quality of life in patients affected by active oncological disease due to the high incidence of pain syndromes, spinal deformity, and neurological impairment. Surgery plays a decisive role in improving quality of life by controlling pain, restoring neurological function and maintaining spinal stability, as well as contributing to the response to medical therapy. Minimally invasive surgery (MIS) is a treatment option in certain patients with high surgical risk since it has a low rate of complications, intraoperative bleeding, hospital stay, and offers similar results to open surgery. In this review, we present the role of MIS in this pathology and some cases treated in our hospital.

The Utility of 'Minimal Access and Separation Surgery' in the Management of Metastatic Spine Disease

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

To compare outcomes of percutaneous pedicle screw fixation (PPSF) to open posterior stabilization (OPS) in spinal instability patients and minimal access separation surgery (MASS) to open posterior stabilization and decompression (OPSD) in metastatic spinal cord compression (MSCC) patients.

METHODS

We analysed patients who underwent surgery for thoracolumbar metastatic spine disease (MSD) from Jan 2011 to Oct 2017. Patients were divided into minimally invasive spine surgery (MISS) and open spine surgery (OSS) groups. Spinal instability patients were treated with PPSF/OPS with pedicle screws. MSCC patients were treated with MASS/OPSD. Outcomes measured included intraoperative blood loss, operative time, duration of hospital stay and ASIA-score improvement. Time to initiate radiotherapy and perioperative surgical/non-surgical complications was recorded. Propensity scoring adjustment analysis was utilised to address heterogenicity of histological tumour subtypes.

RESULTS

Of 200 eligible patients, 61 underwent MISS and 139 underwent OSS for MSD. There was no significant difference in baseline characteristics between MISS and OSS groups. In the MISS group, 28 (45.9%) patients were treated for spinal instability and 33 (54.1%) patients were treated for MSCC. In the OSS group, 15 (10.8%) patients were treated for spinal instability alone and 124 (89.2%) were treated for MSCC. Patients who underwent PPSF had significantly lower blood loss (95 mL vs 564 mL; P < .001) and surgical complication rates(P < .05) with shorter length of stay approaching significance (6 vs 19 days; P = .100) when compared to the OPS group. Patients who underwent MASS had significantly lower blood loss (602 mL vs 1008 mL) and shorter length of stay (10 vs 18 days; P = .098) vs the OPSD group.

CONCLUSION

This study demonstrates the benefits of PPSF and MASS over OPS and OPSD for the treatment of MSD with spinal instability and MSCC, respectively.

Management of Spinal Metastasis by Minimally Invasive Surgical Techniques: Surgical Principles and Indications-A Literature Review

BACKGROUND

Spinal metastasis is becoming more frequent. This raises the topics of pain and neurological complications, which worsen the functional and survival prognosis of oncological population patients. Surgical treatment must be as complete as possible in order to decompress and stabilize without delaying the management of the oncological disease. Minimally invasive spine surgical techniques inflict less damage on the musculocutaneous plan than opened ones.

METHODS

Different minimally invasive techniques are proposed in this paper for the management of spinal metastasis. We used our experience, developed degenerative and traumatic pathologies, and referred to many authors, establishing a narrative review of our local practice.

RESULTS

Forty-eight articles were selected, and these allowed us to describe the different techniques: percutaneous methods such as vertebro/kyphoplasty, osteosynthesis, mini-open surgery, or that through a posterior or anterior approach. Also, some studies detail the contribution of new technologies, such as intraoperative CT scan and robotic assistance.

CONCLUSIONS

It seems essential to offer a lasting solution to a spinal problem, such as in the form of pain relief, stabilization, and decompression. Our department has embraced a multidisciplinary and multidimensional approach to MISS, incorporating cutting-edge technologies and evidence-based practices.

Three-dimensional simulation/printing-assisted surgery for symptomatic metastatic epidural spinal cord compression of posterior column: efficacy assessment based on 2-year follow-up

Background

Surgical intervention is necessary for resolving the symptoms of the spinal cord and nerve compression caused by symptomatic metastatic epidural spinal cord compression. However, surgeons are constantly seeking ways to improve surgical efficiency and safety. This study aims to evaluate the efficacy of 3D simulation/printing-assisted surgery for symptomatic metastatic epidural spinal cord compression of the posterior column.

Methods

We retrospectively analyzed the clinical data of patients who underwent surgical treatment for symptomatic metastatic epidural spinal cord compression of the posterior column in our hospital from January 2015 to January 2020. The simulated group underwent a 3D digital simulation of the lesion area using imaging data before surgery. Twelve patients in the simulated group also received 3D printing, while the direct surgery group did not receive any 3D simulation or printing. All patients were followed up for at least 2 years. We collected clinical data, including operation time, intraoperative blood loss, pedicle screw adjustment rate, intraoperative fluoroscopy times, the incidence of dural injury and cerebrospinal fluid leakage, VAS score, postoperative neurological function improvement, and tumor recurrence. Statistical analysis was performed using SPSS23.0, and P < 0.05 was considered statistically significant.

Results

A total of 46 patients were included in this study, with 20 in the simulated group and 26 in the non-simulated group. The simulated group had better operation time, intraoperative blood loss, screw adjustment rate, fluoroscopy times, and incidence of dural injury/cerebrospinal fluid leakage compared to the non-simulated group. The VAS scores of the two groups improved significantly after the operation and at the last follow-up compared to before the operation. However, there was no statistically significant difference between the two groups. There was also no statistically significant difference in neurological function improvement between the two groups. In the simulated group, 25% of patients relapsed, while in the non-simulated group, 34.61% of patients relapsed. However, there was no statistical difference between the two groups.

Conclusion

Preoperative 3D simulation/printing-assisted surgery is a practical and feasible approach for treating symptomatic metastatic epidural spinal cord compression of the posterior column.

Assessing the accuracy of a new 3D2D registration algorithm based on a non-invasive skin marker model for navigated spine surgery

Purpose

We assessed the accuracy of a new 3D2D registration algorithm to be used for navigated spine surgery and explored anatomical and radiologic parameters affecting the registration accuracy. Compared to existing 3D2D registration algorithms, the algorithm does not need bone-mounted or table-mounted instruments for registration. Neither does the intraoperative imaging device have to be tracked or calibrated.

Methods

The rigid registration algorithm required imaging data (a pre-existing CT scan (3D) and two angulated fluoroscopic images (2D)) to register positions of vertebrae in 3D and is based on non-invasive skin markers. The algorithm registered five adjacent vertebrae and was tested in the thoracic and lumbar spine from three human cadaveric specimens. The registration accuracy was calculated for each registered vertebra and measured with the target registration error (TRE) in millimeters. We used multivariable analysis to identify parameters independently affecting the algorithm’s accuracy such as the angulation between the two fluoroscopic images (between 40° and 90°), the detector-skin distance, the number of skin markers applied, and waist circumference.

Results

The algorithm registered 780 vertebrae with a median TRE of 0.51 mm [interquartile range 0.32–0.73 mm] and a maximum TRE of 2.06 mm. The TRE was most affected by the angulation between the two fluoroscopic images obtained (p < 0.001): larger angulations resulted in higher accuracy. The algorithm was more accurate in thoracic vertebrae (p = 0.004) and in the specimen with the smallest waist circumference (p = 0.003). The algorithm registered all five adjacent vertebrae with similar accuracy.

Conclusion

We studied the accuracy of a new 3D2D registration algorithm based on non-invasive skin markers. The algorithm registered five adjacent vertebrae with similar accuracy in the thoracic and lumbar spine and showed a maximum target registration error of approximately 2 mm. To further evaluate its potential for navigated spine surgery, the algorithm may now be integrated into a complete navigation system.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11548-022-02733-w.

Transtubular image-guided surgery for spinal intradural lesions: techniques, results, and complications in a consecutive series of 60 patients

OBJECTIVE

The authors previously described the image merge tailored access resection (IMTAR) technique for resection of spinal intradural lesions (SIDLs). The authors reported their updated experience with the IMTAR technique and compared surgical results between patients who underwent operations with 2D or 3D fluoroscopic guidance.

METHODS

The authors reviewed 60 patients who underwent SIDL resection with transtubular techniques over a 14-year period. The earlier patients in the series underwent operations with 2D fluoroscopic image guidance. The latter patients underwent operations with the IMTAR technique based on 3D image guidance. The results of both techniques were analyzed.

RESULTS

Sixty patients were included: 27 females (45%) and 33 males (55%). The median (range) age was 50.5 (19-92) years. Gross-total resection (GTR) was achieved in 52 patients (86.7%). Subtotal resection was accomplished in 5 patients (8.3%). Neurological complications occurred in 3 patients (5%), and tumor recurrence occurred in 1 patient (1.7%). The non-IMTAR and IMTAR cohorts showed similar postoperative Nurick scale scores and rates of neurological complications and GTR. The median (interquartile range) bone resection surface area at the index level was 89.5 (51-147) mm2 in the non-IMTAR cohort and 35.5 (11-71) mm2 in the IMTAR cohort, with a statistically significant difference (p = 0.0112).

CONCLUSIONS

Surgery for SIDLs may be challenging, and meticulous surgical planning is crucial to optimize tumor access, maximize resection, and minimize risk of complications. Image-guided transtubular resection is an additional surgical technique for SIDLs and facilitates microsurgical tumor removal of ventrally located lesions with a posterolateral approach, without requiring potentially destabilizing bone resection.

Comparison of open versus minimally invasive surgery in the treatment of thoracolumbar metastases

INTRODUCTION

Minimally invasive surgery (MIS) techniques have been developed for the surgical treatment of thoracolumbar spinal metastases to reduce the morbidity associated with the operation. The purpose of our study was to compare the mean length of stay, change in pain levels, neurological symptoms, complications and survival after open versus MIS surgery.

MATERIAL AND METHODS

This is a single-center retrospective study based on a register of patients treated for vertebral metastases between January 2014 and October 2016. The collection included demographic data, cancer-related data, clinical data, the characteristics of the surgery, the length of stay, assessment of pain and the occurrence of death. These data were compared between open and MIS surgery groups.

RESULTS

Out of 59 patients, 35 were treated with open surgery and 24 were treated with MIS surgery. The two groups were comparable in terms of age, gender and body mass index. Breast, kidney, prostate and lung cancers were the most frequent primary tumors. Prognostic and instability scores were comparable. Short- and medium-term pain assessment showed comparable results. Median survival was 208 days in the open surgery group and 224days in the MIS group (p=0.5299).

CONCLUSION

MIS techniques aim to limit the surgical approach and allow a faster introduction of adjuvant treatments than after open surgery. Our study did not find any differences between open and MIS surgery in terms of pain, neurological evolution or survival time in patients treated for thoracolumbar spinal metastases.

LEVEL OF EVIDENCE

IV; retrospective study.

Posterior Percutaneous Pedicle Screws Fixation Versus Open Surgical Instrumented Fusion for Thoraco-Lumbar Spinal Metastases Palliative Management: A Systematic Review and Meta-analysis

Background

Surgical palliative treatment of spinal metastases (SM) could influence the quality of life (QoL) in cancer patients, since the spine represents the most common site of secondary bony localization. Traditional open posterior instrumented fusion (OPIF) and Percutaneous pedicle screw fixation (PPSF) became the main surgical treatment alternatives for SM, but in Literature there is no evidence that describes the absolute superiority of one treatment over the other.

Materials and Methods

This is a systematic review and meta-analysis of comparative studies on PPSF versus OPIF in patients with SM, conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The outcomes of interest were: complications, blood loss, infections, mortality, pain and also the Quality of Life (QoL).

Results

There were a total of 8 studies with 448 patients included in the meta-analyses. Postoperative complications were more frequent in OPIF (odds ratio of 0.48. 95% CI, 0.27 to 0.83; p= 0.01), PPFS was associated with blood loss (odds ratio -585.70. 95% IC, -848.28 to -323.13.69; p< 0.0001) and a mean hospital stay (odds ratio -3.77. 95% IC, -5.92 to -1.61; p= 0.0006) decrease. The rate of infections was minor in PPFS (odds ratio of 0.31. 95% CI, 0.12 to 0.81; p= 0.02) whereas the occurrence of reinterventions (0.76. 95% CI, 0.25 to 2.27; p= 0.62) and the mortality rate was similar in both groups (odds ratio of 0.79. 95% CI, 0.40 to 1.58; p= 0.51). Finally, we also evaluated pre and post-operative VAS and the meta-analysis suggested that both techniques have a similar effect on pain.

Discussion and Conclusion

The PPSF treatment is related with less complications, a lower rate of infections, a reduction in intraoperative blood loss and a shorter hospital stay compared to the OPIF treatment. However, further randomized clinical trials could confirm the results of this meta-analysis and provide a superior quality of scientific evidence.

Risk factors for wound-related complications after surgical stabilization of spinal metastases with a special focus on the effect of postoperative radiation therapy

BACKGROUND

Advancements in the field of oncological therapies during the last decades have led to a significantly prolonged survival of cancer patients. This has led to an increase in the incidence of spinal metastases. The purpose of this study was to assess risk factors for wound-related complications after surgical stabilization of spinal metastases with a special focus on the effect of postoperative RT and its timing.

METHODS

Patients who had been treated for metastatic spine disease by surgical stabilization followed by radiotherapy between 01/2012 and 03/2019 were included and a retrospective chart review was performed.

RESULTS

Of 604 patients who underwent stabilizing surgery for spinal metastases, 237 patients (mean age 66 years, SD 11) with a mean follow-up of 11 months (SD 7) were eligible for further analysis. Forty-one patients (17.3%) had wound-related complications, 32 of them before and 9 after beginning of the RT. Revision surgery was necessary in 26 patients (11.0%). Body weight (p = 0.021), obesity (p = 0.018), ASA > 2 (p = 0.001), and start of radiation therapy within 21 days after surgery (p = 0.047) were associated with an increased risk for wound complications. Patients with chemotherapy within 3 weeks of surgery (12%) were more likely to have a wound-related surgical revision (p = 0.031).

CONCLUSION

Body weight, obesity and ASA > 2 were associated with an increased risk for wound complications. Patients with chemotherapy within 3 weeks of the surgery were more likely to have a wound-related revision surgery. Patients who had begun radiation therapy within 21 days after surgery were more likely to have a wound complication compared to patients who waited longer.

Analysis of Short-Term versus Long-Term Readmission-Free Survival After Metastatic Spine Tumor Surgery

BACKGROUND

Readmission-free survival (ReAFS) is a novel clinical and quality metric after metastatic spine tumor surgery (MSTS). We believe that factors influencing ReAFS after index MSTS vary based on time. We considered 2 time frames and defined short-term ReAFS as survival without an unplanned hospital readmission up to 90 days and long-term ReAFS as survival without unplanned hospital readmission up to 1 year after MSTS.

METHODS

We retrospectively analyzed 266 patients who underwent MSTS between 2005 and 2016. All relevant oncologic, surgical and follow-up data were collected. Multivariate logistic regression analysis was used to analyze prognostic factors associated with higher probability of short-term ReAFS and long-term ReAFS.

RESULTS

Multivariate analysis showed that Eastern Cooperative Oncology Group score ≤2 (P = 0.011), preoperative hemoglobin (Hb) level >12 g/dL (P = 0.008), ≤3 comorbidities (P = 0.052), shorter index length of stay ≤10 days (P = 0.007), and absence of neurologic/hematologic complications during index stay (P = 0.015) significantly increased the probability of short-term ReAFS, whereas preoperative Hb level >12 g/dL (P = 0.003) or tumor primaries with advanced treatment modalities such as breast (P = 0.012), hematologic (P = 0.006), prostate (P = 0.004), and renal/thyroid (P = 0.038) as opposed to aggressive lung tumor primaries were associated with significantly higher probability of long-term ReAFS.

CONCLUSIONS

Patient and treatment factors predominantly influence ReAFS up to 90 days, whereas primary tumor-related factors alongside general health influence ReAFS beyond 90 days after index MSTS. Awareness of these factors may help oncologists and surgeons optimize treatment planning. The clinical significance of this study will continue to evolve, because we have been witnessing over the past decade that patients are becoming more involved in both their general health and understanding the natural history of the diseases that affect them.

Comparison of Minimally Invasive Tubular Surgery with Conventional Surgery in the Treatment of Thoracolumbar Metastasis

Background

This study aimed to evaluate the perioperative safety and efficacy of minimally invasive tubular surgery for patients with spinal metastasis.

Methods

A total of 161 consecutive patients with spinal metastasis between June 2017 and June 2020 were retrospectively reviewed. A total of 36 patients were included in this study, 14 patients underwent minimally invasive tubular surgery (M), and 22 patients underwent conventional surgery (C). T-test and chi-square tests were used to evaluate demographic and perioperative data differences between the two groups.

Results

Baseline characteristics did not differ significantly between M and C groups except for the SINS (p=0.002) and preoperative Alb (p=0.026). There was no significant difference in operative time and complications between M and C groups (p<0.05). The M group had less mean blood loss than the C group (1275 vs 718mL, p=0.045). Blood transfusion was comparable between the two groups (p<0.05). The mean amount and drainage time were lower than the C group (141 vs 873mL, p<0.001; 3.1 vs 7.0 days, P<0.001). The mean postoperative hospitalization of the M group was 8.8 days, which was lower than the C group (11.3 days, p=0.045). Sub-analysis showed that for patients with hyper-vascular tumor, the M group had less mean amount and time of drainage compared with the C group (p<0.05); for patients with hypo-vascular tumor, the mean blood loss and amount of blood transfusion were also reduced in M group (p<0.05). The mean blood loss and drainage time of patients with hypo-vascular tumors were less than patients with hyper-vascular tumors in the M group (p<0.05).

Conclusion

In selected cases, minimally invasive tubular surgery is safe and effective for patients with spinal metastasis. Patients with hypo-vascular tumors were more suitable for this technique with less blood loss, fewer blood transfusions, minor drainage, and shorter postoperative hospitalization.

Minimal invasive fixation following with radiotherapy for radiosensitive unstable metastatic spine

BACKGROUND

Minimally invasive surgery (MIS) has become a feasible option for patients with spinal metastasis, but the effectiveness of percutaneous pedicle screw fixation (PPSF) without decompression in patients with severe cord compression remains unknown. We compared PPSF without decompression with debulking surgery in patients with radiosensitive, unstable, metastatic thoracolumbar spinal cord compression.

METHODS

A retrospective study of surgically treated spinal metastasis and spinal cord compression patients was conducted between October 2014 and June 2019. Demographic and pre- and postoperative data were collected and compared between patients treated with minimally invasive percutaneous fixation and external beam radiotherapy (EBRT) (the PPSF group) and those treated with debulking surgery (the debulking group).

RESULTS

We included 50 patients in this study. The PPSF group had a significantly shorter operative time (143.56 ± 49.44 min vs. 181.47 ± 40.77 min; p < .01), significantly lower blood loss (116.67 ± 109.92 mL vs. 696.55 ± 519.43 mL; p < .01), and significantly shorter hospital stay (11.90 ± 9.69 vs. 25.35 ± 20.65; p <0.01) than did the debulking group. No significant differences were observed between the groups in age, sex, spinal instability neoplastic score, ESCC, Tomita scores, numeric rating scale scores, American Spinal Injury Association Impairment Scale scores, survival rates, and complication rates. Postoperative neurologic function and decrease in pain were similar between the groups.

CONCLUSION

The PPSF group had a shorter operation time, shorter length of hospital stay, and less blood loss than did the debulking group. PPSF followed by EBRT is pain relieving, relatively safe and appropriate as palliative therapy.

Evaluation of open and minimally invasive spinal surgery for the treatment of thoracolumbar metastatic epidural spinal cord compression: a systematic review

BACKGROUND

Metastatic epidural spinal cord compression (MESCC) is a debilitating sequela of cancer that results in pain, disability, and neurologic deficits. Surgical techniques have included open surgical (OS) techniques with anterior and/or posterior decompression and fusion procedures. Further technical evolution has led to minimally invasive spinal (MIS) decompression and fusion. The objective of this study is to compare MIS to OS techniques in the treatment of thoracolumbar MESCC.

METHODS

A review of the literature was performed using PubMed database. Inclusion criteria included patients 18 years or older, thoracolumbar MESCC, and surgeries with instrumented fusion. A total of 451 articles met the inclusion criteria and further analysis narrowed them down to 81 articles. Variables collected included blood loss, length of stay, operative time, pre- and postoperative Frankel grade, and complications.

RESULTS

A total of 5726 papers were collected, with a total of 81 papers meeting final inclusion criteria: 26 papers with MIS technique and 55 with OS. A total of 2267 patients were evaluated. They were split into three surgical subtypes of MIS and OS: posterior decompression and fusion, partial corpectomy, and complete corpectomy. Overall, MIS had lower operative time, blood loss, and complications compared to OS. A timeline analysis showed reduction of complication rates in MIS surgery between papers published over a 28-year period.

CONCLUSION

MESCC carries significant morbidity and mortality. Surgical approaches for palliative treatment should account for this fact. We conclude that MIS techniques offer a viable alternative to traditional OS approaches with lower overall morbidity and complications.

Short-segment cement-augmented fixation in open separation surgery of metastatic epidural spinal cord compression: initial experience

OBJECTIVE

High-grade metastatic epidural spinal cord compression from radioresistant tumor histologies is often treated with separation surgery and adjuvant stereotactic body radiation therapy. Historically, long-segment fixation is performed during separation surgery with posterior transpedicular fixation of a minimum of 2 spinal levels superior and inferior to the decompression. Previous experience with minimal access surgery techniques and percutaneous stabilization have highlighted reduced morbidity as an advantage to the use of shorter fixation constructs. Cement augmentation of pedicle screws is an attractive option for enhanced stabilization while performing shorter fixation. Herein, the authors describe their initial experience of open separation surgery using short-segment cement-augmented pedicle screw fixation for spinal reconstruction.

METHODS

The authors performed a retrospective chart review of patients undergoing open (i.e., nonpercutaneous, minimal access surgery) separation surgery for high-grade epidural spinal cord compression using cement-augmented pedicle screws at single levels adjacent to the decompression level(s). Patient demographics, treatment data, operative complications, and short-term radiographic outcomes were evaluated.

RESULTS

Overall, 44 patients met inclusion criteria with radiographic follow-up at a mean of 8.5 months. Involved levels included 19 thoracic, 5 thoracolumbar, and 20 lumbar. Cement augmentation through fenestrated pedicle screws was performed in 30 patients, and a vertebroplasty-type approach was used in the remaining 14 patients to augment screw purchase. One (2%) patient required an operative revision for a hardware complication. Three (7%) nonoperative radiographic hardware complications occurred, including 1 pathologic fracture at the index level causing progressive kyphosis and 2 incidences of haloing around a single screw. There were 2 wound complications that were managed conservatively without operative intervention. No cement-related complications occurred.

CONCLUSIONS

Open posterolateral decompression utilizing short-segment cement-augmented pedicle screws is a viable alternative to long-segment instrumentation for reconstruction following separation surgery for metastatic spine tumors. Studies with longer follow-up are needed to determine the rates of delayed complications and the durability of these outcomes.

Comparison of Minimally Invasive Total versus Subtotal Resection of Spinal Tumors: A Systematic Review and Meta-Analysis

OBJECTIVE

With the advent of minimally invasive techniques, minimally invasive spine surgery (MISS) has become a realistic option for many spine cases. This study aims to evaluate the operative and clinical outcomes of MISS for total versus subtotal tumor resection from current evidence.

METHODS

A literature search was performed using the search term (Minimally invasive surgery OR MIS) AND (spine tumor OR spinal tumor). Studies including both minimally invasive total and subtotal resection cases with operative or clinical data were included.

RESULTS

Seven studies describing 159 spinal tumor cases were included. Compared with total resection, subtotal resection showed no significant differences in surgical time (mean difference (MD), 9.44 minutes; 95% confidence interval [CI], -47.66 to 66.55 minutes; P = 0.37), surgical blood loss (MD, -84.72 mL; 95% CI, -342.82 to 173.39 mL; P = 0.34), length of stay (MD, 1.38 days; 95% CI, -0.95 to 3.71 days; P = 0.17), and complication rate (odds ratio, 9.47; 95% CI, 0.34-263.56; P = 0.12). Pooled analyses with the random-effects model showed that neurologic function improved in 89% of patients undergoing total resection, whereas neurologic function improved in 61% of patients undergoing subtotal resection.

CONCLUSIONS

Our analyses show that there is no significant difference in operative outcomes between total and subtotal resection. Patients undergoing total resection showed slightly better improvement in neurologic outcomes compared with patients undergoing subtotal resection. Overall, this study suggests that both total and subtotal resection may result in comparable outcomes for patients with spinal tumors. However, maximal safe resection remains the ideal treatment because it provides the greatest chance of long-term benefit.

Is Less Really More? Economic Evaluation of Minimally Invasive Surgery

STUDY DESIGN

Review.

OBJECTIVE

A comparative overview of cost-effectiveness between minimally invasive versus and equivalent open spinal surgeries.

METHODS

A literature search using PubMed was performed to identify articles of interest. To maximize the capture of studies in our initial search, we combined variants of the terms "cost," "minimally invasive," "spine," "spinal fusion," "decompression" as either keywords or MeSH terms. PearlDiver database was queried for open and minimally invasive surgery (MIS; endoscopic or percutaneous) reimbursements between Q3 2015 and Q2 2018.

RESULTS

In general, MIS techniques appeared to decrease blood loss, shorten hospital lengths of stay, mitigate complications, decrease perioperative pain, and enable quicker return to daily activities when compared to equivalent open surgical techniques. With regard to cost, primarily as a result of these latter benefits, MIS was associated with lower costs of care when compared to equivalent open techniques. However, cost reporting was sparse, and relevant methodology was inconsistent throughout the spine literature. Within the PearlDiver data sets, MIS approaches had lower reimbursements than open approaches for both lumbar posterior fusion and discectomy.

CONCLUSIONS

Current data suggests that overall cost-savings may be incurred with use of MIS techniques. However, data reporting on costs lacks in uniformity, making it difficult to formulate any firm conclusions regarding any incremental improvements in cost-effectiveness that may be incurred when utilizing MIS techniques when compared to equivalent open techniques.

Minimal Invasive Surgery Instrumented Fusion versus Conventional Open Surgical Instrumented Fusion for the Treatment of Spinal Metastases: A Systematic Review and Meta-analysis

OBJECTIVE

In this study, we aimed to compare the minimally invasive surgery (MIS) instrumented fusion ± decompression versus conventional open surgery (COS) instrumented fusion ± decompression for the treatment of spinal metastases.

METHODS

We performed a systematic literature search through PubMed, Scopus, Europe PMC (PubMed Central), and Cochrane Central Database using the keywords "minimal invasive surgery" OR "minimally invasive surgery" OR "mini-open" AND "conventional open surgery" OR "traditional open surgery" OR "open surgery" AND "spinal metastasis". The outcomes of interest were complications, neurologic improvement, length of stay, intraoperative blood loss, transfusion rate, and operative duration.

RESULTS

There were a total of 8 studies comprising 486 patients. Complications were less frequent in MIS compared with COS (odds ratio [OR], 0.51; 95% confidence interval [CI], 0.30-0.84; P = 0.01; I² = 0%). Major complications related to surgery were less in the MIS group (OR, 0.42; 95% CI, 0.21-0.84; P = 0.01; I² = 0%). The rate of neurologic improvement was similar in both groups (OR, 1.01; 95% CI, 0.64-1.59; P = 0.95; I² = 0%). MIS was associated with less blood loss (mean difference, -690.00 mL; 95% CI, -888.31 to -491.69; P < 0.001; I² = 56%), and lower transfusion rate compared with COS (OR, 0.27; 95% CI, 0.11-0.66; P = 0.004; I² = 50%). Length of surgery was similar in both groups (mean difference, -12.49 minutes; 95% CI, -45.93 to 20.95; P = 0.46; I² = 86%). MIS resulted in shorter length of stay compared with COS (mean difference -3.58 days; 95% CI, -6.90 to -0.26; P = 0.03; I² = 89%).

CONCLUSIONS

MIS was associated with lower complications, blood loss, transfusion rate, and shorter length of stay with a similar rate of neurologic improvement and length of surgery compared with COS.

Readmission-Free Survival Analysis in Metastatic Spine Tumour Surgical Patients: A Novel Concept

BACKGROUND

Outcomes commonly used to ascertain success of metastatic spine tumour surgery (MSTS) are 30-day complications/mortality and overall/disease-free survival. We believe a new, effective outcome indicator after MSTS would be the absence of unplanned hospital readmission (UHR) after index discharge. We introduce the concept of readmission-free survival (ReAFS), defined as 'the time duration between hospital discharge after index operation and first UHR or death'. The aim of this study is to identify factors influencing ReAFS in MSTS patients.

PATIENTS AND METHODS

We retrospectively analysed 266 consecutive patients who underwent MSTS between 2005 and 2016. Demographics, oncological characteristics, procedural, preoperative and postoperative details were collected. ReAFS of patients within 2 years or until death was reviewed. Perioperative factors predictive of reduced ReAFS were evaluated using multivariate regression analysis.

RESULTS

Of 266 patients, 230 met criteria for analysis. A total of 201 had UHR, whilst 1 in 8 (29/230) had no UHR. Multivariate analysis revealed that haemoglobin ≥ 12 g/dL, ECOG score of ≤ 2, primary prostate, breast and haematological cancers, comorbidities ≤ 3, absence of preoperative radiotherapy and shorter postoperative length of stay significantly prolonged the time to first UHR.

CONCLUSIONS

Readmission-free survival is a novel concept in MSTS, which relies on patients' general condition, appropriateness of interventional procedures and underlying disease burden. Additionally, it may indicate the successful combination of a multi-disciplinary treatment approach. This information will allow oncologists and surgeons to identify patients who may benefit from increased surveillance following discharge to increase ReAFS. We envisage that ReAFS is a concept that can be extended to other surgical oncological fields.

In the Extraordinary Times of Coronavirus Disease 2019: Clinical Strategies for Performing Spinal Surgery

The coronavirus disease 2019 (COVID-19) pandemic has caused pronounced strain on global healthcare systems, forcing the streamlining of clinical activities and conservation of health resources. There is a pressing need for institutions to present discipline-specific strategies for the management of COVID-19 patients. We present the comprehensive considerations at the National University Hospital, Singapore from the surgeon’s and anesthetist’s perspectives in the performance of spinal surgery in COVID-19 patients. These are based on national guidelines and overarching principles of protection for the healthcare workers (HCWs) and efficiency in surgical planning. The workflow begins with the emergency department screening that has been adapted to the local epidemiology of COVID-19 in order to identify suspected/confirmed cases. If patient history cannot be obtained, demographic, clinical, and imaging data are used. Designated orthopedic “contaminated teams” are available 24/7 with an activation time of <30 minutes for review. In cases where sub-specialty spine surgeons were required, these professionals were inducted into the “contaminated team” and quarantined until cleared to return to work. Indications for emergency spine surgery were determined pre-emptively. Preoperative surgical considerations included the minimization of manpower, limited dissection, reduced operative time, and judicious use of equipment, leading to reduced aerosolization. Anesthesia considerations include preoperative screening for COVID-19–related concerns that influence surgery, operating room process planning and induction, intraoperative, reversal, recovery, and resuscitation considerations. Focused multi-disciplinary preoperative briefing facilitates familiarization. Surgical, anesthetic, and postoperative workflows were designed to reduce the risk of transmission and protect HCWs while effectively performing spinal surgery. The COVID-19 pandemic has necessitated paradigm shifts in healthcare planning, hospital workflows, and operative protocols. The viral burden does not discriminate between surgeons and physicians, and it is crucial that we, as medical professionals, adapt practices to be malleable and fluid to address the ever-changing developments.

Minimally Invasive Pedicle Screw Fixation With Indirect Decompression by Ligamentotaxis in Pathological Fractures

BACKGROUND

The spine is the most common site of bony metastases. Associated pathological fractures can result in pain, neurological deficit, biomechanical instability, and deformity.

OBJECTIVE

To present a minimally invasive technique for indirect decompression by ligamentotaxis in pathological fractures.

METHODS

A minimally invasive approach was utilized to perform percutaneous pedicle screw fixation in patients who required stabilization for pathological fractures. Preoperative and postoperative computed tomography and magnetic resonance imaging were used to compare spinal canal area and midsagittal canal diameter.

RESULTS

Two patients with newly diagnosed pathological fractures underwent minimally invasive treatment. Each presented with minimal epidural disease and a chief complaint of intractable back pain without neurological deficit. They underwent minimally invasive pedicle screw fixation with indirect decompression by ligamentotaxis. In each case, postoperative imaging demonstrated an increase in spinal canal area and midsagittal canal diameter by an independent neuroradiologist. There were no perioperative complications, and each patient was neurologically stable without evidence of hardware failure at their 5- and 6-mo follow-up visits.

CONCLUSION

Minimally invasive percutaneous fixation can be used to stabilize pathological fractures and provide indirect decompression by ligamentotaxis. This procedure is associated with minimal blood loss, low morbidity, and rapid initiation of radiation therapy. Only patients with minimal epidural disease, stenosis caused primarily by bony retropulsion, and mild-to-moderate deformity should be considered candidates for this approach.

Minimally Invasive Pedicle Screw Fixation Combined with Percutaneous Kyphoplasty Under O-Arm Navigation for the Treatment of Metastatic Spinal Tumors with Posterior Wall Destruction

OBJECTIVE

To evaluate the safety and efficacy of O-arm-guided minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for metastatic spinal tumors with posterior wall destruction.

METHODS

Patients who underwent minimally invasive pedicle screw fixation combined with percutaneous kyphoplasty for pathological vertebral fractures with posterior wall defects from January 2015 to December 2017 were followed up for 1 year. Visual analogue scale (VAS), SF-36 scores, middle vertebral height, posterior vertebral height, and the accuracy of pedicle screws were assessed preoperatively, postoperatively, and 1 year after surgery. The operation time, time from operation to discharge, blood loss, volume of bone cement, and leakage of bone cement were recorded.

RESULTS

Twenty-three patients (13 females and 10 males) who met our criteria were followed up for 1 year. The operation time of these patients was 162.61 ± 33.47 min, the amount of bleeding was 230.87 ± 93.76 mL, the time from operation to discharge was 4.35 ± 2.42 days, and the volume of bone cement was 3.67 ± 0.63 mL. The VAS score decreased from 7.04 ± 1.07 to 2.65 ± 0.93 before surgery (P = 0.000) and remained at 2.57 ± 0.79 1 year after surgery. Compared with the preoperative SF-36 scores for physical pain, physiological function, energy, and social function, the postoperative scores were significantly improved (P = 0.000). The height of the middle vertebral body increased from 14.47 ± 2.96 mm before surgery to 20.18 ± 2.94 mm (P = 0.000), and remained at 20.44 to 3.01 mm 1 year after surgery. The height of the posterior vertebral body increased from 16.56 ± 3.07 mm before operation to 22.79 ± 4.00 mm (P = 0.000), and 22.45 ± 3.88 mm 1 year after surgery. The 23 patients had a total of 92 pedicle screws; 85 screws were Grade A and 7 screws were Grade B. There was no leakage of bone cement after surgery.

CONCLUSION

In the short term, O-arm-guided minimally invasive pedicle screw fixation combined with kyphoplasty is safe and effective in the treatment of metastatic spinal tumors with posterior wall destruction.

Minimally Invasive Separation Surgery for Metastases in the Vertebral Column: A Technical Report

BACKGROUND

Epidural spinal cord compression (ESCC) is a common and severe cause of morbidity in cancer patients. Minimally invasive surgical techniques may be utilized to preserve neurological function and permit the use of radiation to maximize local control. Minimally invasive techniques are associated with lower morbidity.

OBJECTIVE

To describe a novel, minimally invasive operative technique for the management of metastatic ESCC.

METHODS

A minimally invasive approach was used to cannulate the pedicles of the thoracic vertebrae, which were then held in place by Kirschner wires (K-wires). Following open decompression of the spinal cord, cannulated screws were placed percutaneously with stereotactic guidance through the pedicles followed by cement induction. Stereotactic radiosurgery is performed in the postoperative period for residual metastatic disease in the vertebral body.

RESULTS

The minimally invasive technique used in this case reduced tissue damage and optimized subsequent recovery without compromising the quality of decompression or the extent of metastatic tumor resection. Development of more minimally invasive techniques for the management of metastatic ESCC has the potential to facilitate healing and preserve quality of life in patients with systemic malignancy.

CONCLUSION

ESCC from vertebral metastases poses a challenge to treat in the context of minimizing potential risks to preserve quality of life. Percutaneous pedicle screw fixation with cement augmentation provides a minimally invasive alternative for definitive treatment of these patients.

The Role of Minimal Access Surgery in the Treatment of Spinal Metastatic Tumors

STUDY DESIGN

Literature review.

OBJECTIVE

To provide an overview of the recent advances in minimal access surgery (MAS) for spinal metastases.

METHODS

Literature review.

RESULTS

Experience gained from MAS in the trauma, degenerative and deformity settings has paved the road for MAS techniques for spinal cancer. Current MAS techniques for the treatment of spinal metastases include percutaneous instrumentation, mini-open approaches for decompression and tumor resection with or without tubular/expandable retractors and thoracoscopy/endoscopy. Cancer care requires a multidisciplinary effort and adherence to treatment algorithms facilitates decision making, ultimately improving patient outcomes. Specific algorithms exist to help guide decisions for MAS for extradural spinal metastases. One major paradigm shift has been the implementation of percutaneous stabilization for treatment of neoplastic spinal instability. Percutaneous stabilization can be enhanced with cement augmentation for increased durability and pain palliation. Unlike osteoporotic fractures, kyphoplasty and vertebroplasty are known to be effective therapies for symptomatic pathologic compression fractures as supported by high level evidence. The integration of systemic body radiation therapy for spinal metastases has eliminated the need for aggressive tumor resection allowing implementation of MAS epidural tumor decompression via tubular or expandable retractors and preliminary data exist regarding laser interstitial thermal therapy and radiofrequency ablation for tumor control. Neuronavigation and robotic systems offer increased precision, facilitating the role of MAS for spinal metastases.

CONCLUSIONS

MAS has a significant role in the treatment of spinal metastases. This review highlights the current utilization of minimally invasive surgical strategies for treatment of spinal metastases.

[Intraoperative and late complications after spinal tumour resection and dorsoventral reconstruction]

BACKGROUND

Spinal tumors are a continuously growing pathology group among the spinal diseases. The often-difficult circumstances increase vulnerability to a wide range of intervention-related complications, which can occur at different times in the course of the disease and must be included in the consideration of the indication.

OBJECTIVES

The aim of the work is to present the wide spectrum of complications in the surgical treatment of spinal tumors, as well as their treatment and prophylaxis through optimal therapy management.

MATERIALS AND METHODS

The article summarizes the current literature.

RESULTS

The literature describes complication rates of 10-67% after metastatic surgery of the spinal column. The most common complications are infections and internal, especially pulmonary, complications. Other relevant complications include surgical positioning/surgical access/instrumentation/mechanical failure, and anesthesiological, neurological, vascular and oncological complications. The socio-economic costs for patients with complications compared to those for patients without complications are twice as high. A special risk situation exists with radical spinal tumor resections. Negative predictors are previous operations, previous irradiation and local recurrences.

CONCLUSIONS

An early, interdisciplinary concept can reduce complications significantly. Due to the planning intensity, surgical expertise and comprehensive structural requirements, treatment in an interdisciplinary tumour centre is necessary.

Decision Making in Patients With Metastatic Spine. The Role of Minimally Invasive Treatment Modalities

Spine metastases affect more than 70% of terminal cancer patients that eventually suffer from severe pain and neurological symptoms. Nevertheless, in the overwhelming majority of the cases, a spinal metastasis represents just one location of a diffuse systemic disease. Therefore, the best practice for treatment of spinal metastases depends on many different aspects of an oncological disease, including the assessment of neurological status, pain, location, and dissemination of the disease as well as the ability to predict the risk of disease progression with neurological worsening, benefits and risks associated to treatment and, eventually, expected survival. To address this need for a framework and algorithm that takes all aspects of care into consideration, we reviewed available evidence on the multidisciplinary management of spinal metastases. According to the latest evidence, the use of stereotactic radiosurgery (SRS) or stereotactic body radiotherapy (SBRT) for spinal metastatic disease is rapidly increasing. Indeed, aggressive surgical resection may provide the best results in terms of local control, but carries a significant rate of post-surgical morbidity whose incidence and severity appears to be correlated to the extent of resection. The multidisciplinary management represents, according to current evidence, the best option for the treatment of spinal metastases. Noteworthy, according to the recent literature evidence, cases that once required radical surgical resection followed by low-dose conventional radiotherapy, can now be more effectively treated by minimally invasive spinal surgery (MISS) followed by spine SRS with decreased morbidity, improved local control, and more durable pain control. This combination allows also extending this standard of care to patients that would be too sick for an aggressive surgical treatment.

Essential Concepts for the Management of Metastatic Spine Disease: What the Surgeon Should Know and Practice

STUDY DESIGN

Literature review.

OBJECTIVE

To provide an overview of the recent advances in spinal oncology, emphasizing the key role of the surgeon in the treatment of patients with spinal metastatic tumors.

METHODS

Literature review.

RESULTS

Therapeutic advances led to longer survival times among cancer patients, placing significant emphasis on durable local control, optimization of quality of life, and daily function for patients with spinal metastatic tumors. Recent integration of modern diagnostic tools, precision oncologic treatment, and widespread use of new technologies has transformed the treatment of spinal metastases. Currently, multidisciplinary spinal oncology teams include spinal surgeons, radiation and medical oncologists, pain and rehabilitation specialists, and interventional radiologists. Consistent use of common language facilitates communication, definition of treatment indications and outcomes, alongside comparative clinical research. The main parameters used to characterize patients with spinal metastases include functional status and health-related quality of life, the spinal instability neoplastic score, the epidural spinal cord compression scale, tumor histology, and genomic profile.

CONCLUSIONS

Stereotactic body radiotherapy revolutionized spinal oncology through delivery of durable local tumor control regardless of tumor histology. Currently, the major surgical indications include mechanical instability and high-grade spinal cord compression, when applicable, with surgery providing notable improvement in the quality of life and functional status for appropriately selected patients. Surgical trends include less invasive surgery with emphasis on durable local control and spinal stabilization.

Clinical Results of Minimally Invasive Spine Stabilization for the Management of Metastatic Spinal Tumors Based on the Epidural Spinal Cord Compression Scale

Purpose

Minimally invasive spine stabilization (MISt) using percutaneous pedicle screws plays a significant role in palliative surgery for metastatic spinal tumors. However, few studies have investigated surgical outcomes based on the epidural spinal cord compression scale (ESCCS). The purpose of this study was to examine outcomes of metastatic spinal tumors as evaluated by ESCCS in patients treated by MISt.

Methods

The subjects were 56 patients who underwent MISt for metastatic spinal tumors, including 34 patients with ESCCS 2 or milder (group A) and 22 patients with ESCCS 3 (group B). We analyzed baseline characteristics, perioperative factors and clinical results such as postoperative survival time, neurological outcomes, Barthel Index for activities of daily living (ADL), visual analogue scale (VAS), and the rate of discharge to home.

Results

The baseline age (P=0.07), tumor diagnosis (P=0.23), spinal level of compression (P=0.35), American Spinal Injury Association classification (P=0.49), revised Tokuhashi score (P=0.92), spinal instability neoplastic score (P=0.28), VAS (P=0.35), Barthel Index (P=0.07), American Society of Anesthesiologists physical status classification (P=0.76), and type of surgery (P=0.40) did not differ significantly between the two groups. The median postoperative survival time did not differ significantly between the groups (12.0 versus 15.0 months, P=0.60). Neurological improvement by at least 1 grade or maintenance of grade E was favorable in group A. Patients in group A had less posterior decompression (P=0.006), a higher rate of chemotherapy (P=0.009), a higher postoperative Barthel Index (P=0.04), and a higher rate of discharge to home (P=0.01) and no patients died in the hospital (P=0.004).

Conclusions

No significant difference was noted in the postoperative survival time between the 2 groups. Patients in the ESCCS 2 or milder group had favorable neurological improvement, higher rates of chemotherapy, better postoperative ADL, and the higher rate of discharge to home.

Minimal Access Surgery for Spinal Metastases: Prospective Evaluation of a Treatment Algorithm Using Patient-Reported Outcomes

BACKGROUND

Minimal access surgery (MAS) allows for an early return to systemic and radiation therapy in patients with cancer, leading to its increasing usage in the treatment of spinal metastases. Systematic examination of surgical indications resulted in the development of an algorithm for implementation of MAS in the treatment of spinal metastases. The objective of the present study was to evaluate a spine tumor MAS treatment algorithm using patient-reported outcomes for patients with cancer undergoing treatment of spinal metastases.

METHODS

We performed a prospective cohort study of patients who had undergone spinal percutaneous instrumented stabilization with the addition of MAS spinal cord or nerve root decompression and/or kyphoplasty when indicated at a tertiary cancer center from December 2013 to August 2016. Validated patient-reported outcome measures, including the Brief Pain Inventory and the MD Anderson Symptom Inventory-spine module, were used. The patient-reported outcome measures were collected and compared at baseline, 3 months, and long-term follow-up (range, 4.5-12 months).

RESULTS

A total of 51 patients were included. MAS resulted in a statistically significant decrease in the severity of pain and improved activity, ability to work, and enjoyment of life (P < 0.001). The improvement was reported at the short- and long-term follow-up points.

CONCLUSIONS

We present our treatment algorithm for MAS implementation in the treatment of thoracolumbar spinal metastases. Prospectively collected data have demonstrated that using this algorithm, MAS surgery for the treatment of spinal metastases results in significant decreases in pain severity and symptom interference with daily activities.

Comparison between minimally invasive spine stabilization with and without posterior decompression for the management of spinal metastases: a retrospective cohort study

Background

Posterior decompression and stabilization plays significant roles in palliative surgery for metastatic spinal tumor. However, the indication for addition of posterior decompression have not been examined. The purpose of this study was to investigate a retrospective cohort of outcomes of metastatic spinal tumor treated with minimally invasive spine stabilization (MISt) with or without posterior decompression.

Methods

The subjects were 40 patients who underwent MISt using percutaneous pedicle screws for metastatic spinal tumor, including 20 patients treated with stabilization alone (group A) and 20 patients with added posterior decompression (group B). We analyzed baseline characteristics, postoperative survival time, and perioperative factors such as neurological outcomes, Barthel Index, VAS, and rate of discharge to home.

Results

The mean ages were 70 and 66 years old (P = 0.06), the mean revised Tokuhashi scores were 7.2 and 5.8 (P = 0.1), the mean spinal instability neoplastic scores (SINS) were 10.5 and 9.0 (P = 0.04), and the mean Barthel Index for ADL were 65.5 and 41.0 (P = 0.06) in groups A and B, respectively. The median postoperative survival time did not differ significantly between groups A and B (12.0 vs. 6.0 months, P = 0.09). Patients in group A had a significantly shorter operation time (166 vs. 232 min, P = 0.004) and lower intraoperative blood loss (120 vs. 478 mL, P < 0.001). Postoperative paralysis (P = 0.1), paralysis improvement rate (P = 0.09), postoperative Barthel Index (P = 0.06), and postoperative VAS (P = 0.6) did not differ significantly between the groups. The modified Frankel classification improved from D1 or D2 before surgery to D3 or E after surgery in 4 of 10 cases (40%) in group A and 8 of 8 patients (100%) in group B (P = 0.01). Significantly more patients were discharged to home in group A (P = 0.02), whereas significantly more patients died in the hospital in group B (P = 0.02).

Conclusions

Patients treated without decompression had a shorter operation time, less blood loss, a higher rate of discharge to home, and lower in-hospital mortality, indicating a procedure with lower invasiveness. MISt without decompression is advantageous for patients with D3 or milder paralysis, but decompression is necessary for patients with D2 or severer paralysis.

Minimally invasive versus conventional spine surgery for vertebral metastases: a systematic review of the evidence

One of the major determinants of surgical candidacy in patients with symptomatic spinal metastases is the ability of the patient to tolerate the procedure-associated morbidity. In other pathologies, minimally invasive (MIS) procedures have been suggested to have lower intra-operative morbidity while providing similar outcomes. We conducted a systematic review of the PubMed library searching for articles that directly compared the operative and post-operative outcomes of patients treated for symptomatic spinal metastases. Inclusion criteria were articles reporting two or more cases of patients >18 years old treated with MIS or open approaches for spinal metastases. Studies reporting results in spinal metastases patients that could not be disentangled from other pathologies were excluded. Our search returned 1,568 articles, of which 9 articles met the criteria for inclusion. All articles were level III evidence. Patients treated with MIS approaches tended to have lower intraoperative blood loss, shorter operative times, shorter inpatient stays, and fewer complications relative to patients undergoing surgeries with conventional approaches. Patients in the MIS and open groups had similar pain improvement, neurological improvement, and functional outcomes. Recent advances in MIS techniques may reduce surgical morbidity while providing similar symptomatic improvement in patients treated for spinal metastases. As a result, MIS techniques may expand the pool of patients with spinal metastases who are candidates for operative management.

State of the Art Treatment of Spinal Metastatic Disease

Treatment paradigms for patients with spine metastases have evolved significantly over the past decade. Incorporating stereotactic radiosurgery into these paradigms has been particularly transformative, offering precise delivery of tumoricidal radiation doses with sparing of adjacent tissues. Evidence supports the safety and efficacy of radiosurgery as it currently offers durable local tumor control with low complication rates even for tumors previously considered radioresistant to conventional radiation. The role for surgical intervention remains consistent, but a trend has been observed toward less aggressive, often minimally invasive, techniques. Using modern technologies and improved instrumentation, surgical outcomes continue to improve with reduced morbidity. Additionally, targeted agents such as biologics and checkpoint inhibitors have revolutionized cancer care, improving both local control and patient survivals. These advances have brought forth a need for new prognostication tools and a more critical review of long-term outcomes. The complex nature of current treatment schemes necessitates a multidisciplinary approach including surgeons, medical oncologists, radiation oncologists, interventionalists, and pain specialists. This review recapitulates the current state-of-the-art, evidence-based data on the treatment of spinal metastases, integrating these data into a decision framework, NOMS, which integrates the 4 sentinel decision points in metastatic spine tumors: Neurologic, Oncologic, Mechanical stability, and Systemic disease and medical co-morbidities.

The Influence of Histologic Subtype in Predicting Survival of Lung Cancer Patients With Spinal Metastases

STUDY DESIGN

Retrospective analysis.

SUMMARY OF BACKGROUND DATA

Recent advancements in systemic treatment of lung cancer have significantly improved the survival of patients with certain histolopathologic and molecular subtypes. Existing prognostic scores do not account for this and patients with lung cancer spinal metastases are grouped together as poor prognostic candidates, and consequently, some may be inappropriately denied palliative spine surgery.

OBJECTIVE

The objective of the study was to study whether the expected survival in patients with lung cancer spinal metastases is affected by histolopathologic and molecular subtypes in the context of modern systemic therapy.

MATERIALS AND METHODS

We retrospectively reviewed all patients with histologically confirmed lung cancer treated for spinal metastases at our institution between 2001 and 2012. Patients' demographics, histopathologic details, treatment modalities, and survival data were collected. The primary outcome was survival from time of spinal metastases diagnosis. The Cox regression analysis was used to evaluate the influence of tumor histology, molecular profile and treatment modality on survival. The Kaplan-Meier survival analysis was conducted to compare lung cancer subtypes, as well as various treatment regimens.

RESULTS

Out of 180 patients, 51 underwent surgery for spinal metastases. Female sex (P=0.019), absence of palsy (P=0.023), good Karnofsky performance scores (P<0.001), and non-small cell lung cancer (NSCLC) (P=0.002) were favorable prognostic factors. Patients who received systemic therapy, including tyrosine kinase inhibitors, platinum doublet chemotherapy, or both showed increased survival (P<0.01). The median survival time was 2.40 months [95% confidence interval (CI), 2.13-2.68] in the small cell lung cancer cohort, with no patients surviving past a year; 5.10 months (95% CI, 3.78-6.41) in the NSCLC cohort, with 25.9% 1-year survival; and 13.3 months (95% CI, 2.26-24.40) in adenocarcinoma patients who received both tyrosine kinase inhibitors and platinum doublet therapy, with 50.0% 1-year survival.

CONCLUSIONS

NSCLC, systemic therapy, female sex, absence of palsy and good Karnofsky performance scores are all independent favorable prognostic factors for patients with lung cancer spinal metastases. These should be routinely considered during prognostication.

Patient-reported outcomes after surgical stabilization of spinal tumors: symptom-based validation of the Spinal Instability Neoplastic Score (SINS) and surgery

BACKGROUND CONTEXT

Neoplastic spinal instability is movement-related pain or neurologic compromise under physiologic loads with the Spinal Instability Neoplastic Score (SINS) developed to facilitate diagnosis. There is a paucity of evidence that mechanical instability correlates with patient-reported symptoms and that surgical stabilization significantly improves these patient-reported outcomes (PROs).

PURPOSE

The objective of this study was to determine if SINS correlates with patient-reported preoperative pain and disability, and if surgical stabilization significantly improves PRO.

STUDY DESIGN

A single-institution prospective cohort study was carried out.

PATIENT SAMPLE

A total of 131 patients who underwent stabilization for metastatic spinal tumor treatment between July 2014 and August 2016 were included.

OUTCOMES MEASURES

Preoperative baseline and mean difference in perioperative PROs as assessed by the Brief Pain Inventory (BPI) and MD Anderson Symptom Inventory (MDASI) were the outcome measures.

METHODS

The SINS was analyzed as a continuous, ordinal, and categorical variable (Stable: 0-6, Indeterminate: 7-12, Unstable: 13-18). Statistical analysis was performed using Spearman rank coefficient (rho), the Kruskal-Wallis test, and an extension of the Cochran-Armitage trend test. The SINS and association between the mean differences in post- and preoperative PRO scores was analyzed using the Wilcoxon signed-rank test.

RESULTS

There was a statistically significant positive correlation between increasing SINS and severity of preoperative pain with BPI average pain (rho=0.20; p=.03) and MDASI pain (rho=0.19; p=.03). Increasing SINS correlated with severity of preoperative disability with BPI walking (rho=0.19; p=.04), MDASI activity (rho=0.24; p=.006), and MDASI walking (rho=0.20; p=.03). Similar associations were noted when SINS was analyzed as an ordinal categorical variable. Stabilization significantly improved nearly all PRO measures for patients with indeterminate and unstable SINS. Significant correlations persisted when controlling for neurologic status and were not affected based on the technique of surgical stabilization used.

CONCLUSIONS

Patient-related outcome-based validation of SINS confirms this scoring system for diagnosing neoplastic spinal instability and provides surgeons with a tool to determine which patients will benefit from stabilization. Surgical stabilization of cancer patients with SINS consistent with mechanical instability provides significant reduction in pain and improves patient mobility independent of neurologic status and stabilization technique.

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.

Minimally invasive "separation surgery" plus adjuvant stereotactic radiotherapy in the management of spinal epidural metastases

Aim:

This study aimed to describe the application of minimally invasive surgery (MIS) in separation surgery combined with postoperative stereotactic body radiation therapy (SBRT) in patients with symptomatic metastatic epidural spinal disease.

Methods:

Three techniques are described: (1) MIS posterior separation surgery alone, (2) MIS posterolateral separation surgery with percutaneous pedicle screw placement, and (3) MIS lateral corpectomy with percutaneous pedicle screw placement. Seven representative cases are presented in which the above techniques were applied and after which postoperative SBRT was performed.

Results:

The seven representative patients (3 male, 4 female) had a mean age of 54 years (range, 46–62 years). Two patients had a primary diagnosis of cholangiocarcinoma and in one patient each a diagnosis of breast, renal, lung adenocarcinoma, melanoma, and urothelial squamous cell carcinoma as their primary tumor. All patients had additional multiorgan disease apart from the metastatic spine involvement. Three patients underwent operations in the lumbar spine, two in the thoracic spine, and one in each of the thoraco-lumbar and lumbo-sacral spine. The average operating time was 149 ± 60.3 min (range, 90–240 min). The mean estimated blood loss was 188.8 cc. The mean length of stay in the hospital was 4 days (range, 3–7 days). There were no surgical complications. All patients received postoperative SBRT (typically 24 Gy in 3 fractions) at a mean of 43.2 days after surgery (range, 30–83).

Conclusions:

Early reports such as this suggest that MIS techniques can be successfully and safely applied in accomplishing “separation surgery” with adjuvant SBRT in the management of metastatic spinal disease. The potential advantages conferred by MIS techniques such as shortened hospital stay, decreased blood loss, reduced perioperative complications, and earlier initiation of adjuvant radiation are highly desirable in the treatment of this challenging patient population.