Total en bloc spondylectomy for spinal tumors: surgical techniques and related basic background

Unusual Presentation of Thoracic Chordoma with Spinal Epidural Hematoma: A Rare Case Report and PRISMA-Driven Systematic Review

A chordoma is a slow growing, locally invasive, low-grade tumor belonging to the sarcoma family. It mainly affects the sacrum and skull base. We present a case of thoracic chordoma initially presented with epidural hematoma (EDH), which is a rare clinical entity. We reported this case, and also performed a PRISMA-driven systematic review to summary the similar cases in the literature. This review includes the clinical characteristics and outcome of thoracic chordoma. Our case involves a 60-year-old male who, despite no history of trauma, presented with acute paraparesis. An epidural hematoma was identified at T6 level, leading to a surgical intervention involving T4-6 laminectomy and fixation. Six months subsequent to surgery, the patient experienced progressive lower limb weakness and spasticity. Computed tomography (CT) exhibited erosion of T6 and an associated aggressive mass. Magnetic resonance imaging (MRI) revealed a large heterogenous soft tissue mass arising from the vertebral body and right pedicle of D6, protruding in the epidural space and compressing the spinal cord focally at this level. The mass measured approximately 5 × 4 × 3.5 cm. Magnetic resonance myelography indicated a filling defect at T5-6 level, confirming the intraspinal location of the soft tissue lesion. Complete excision of the mass confirmed the diagnosis of thoracic chordoma. Postoperative follow-up demonstrated notable improvement in the lower limb spasticity and paraparesis, and the patient started adjuvant radiotherapy. This case underscores the importance of maintaining a high index of suspicion when evaluating presentations resembling EDH.

Pre-operative spine tumour embolization: Clinical outcomes and effect of embolization completeness

INTRODUCTION

To assess the association between the impact of the completeness of pre-operative spine tumour embolisation and clinical outcomes, including estimated blood loss (EBL), neurological status and complications.

METHODS

Retrospective chart review of all preoperative spine tumour embolisation procedures performed over 11 years by a single operator (2007-2018) at Vancouver General Hospital on 44 consecutive patients (mean age 57; 77% males) with 46 embolisation procedures, of which surgery was done en bloc in 26 cases and intralesional in the remaining 20. A multivariable negative binomial regression model was fit to examine the association between EBL and surgery type, tumour characteristics, embolisation completeness and operative duration.

RESULTS

Among intralesional surgeries, complete versus incomplete embolisation was associated with reduced blood loss (772 vs 1428 mL, P < 0.01). There was no statistically significant difference in neurological outcomes or complications between groups. Highly vascular tumours correlated with greater blood loss than their less vascular counterparts, but tumour location did not have a statistically significant effect.

CONCLUSION

This study provides evidence in support of our hypothesis that complete as opposed to incomplete tumour embolisation correlates with reduced blood loss in intralesional surgeries. Randomised control trials with larger samples are necessary to confirm this benefit and to ascertain other potential clinical benefits.

New technique of En bloc vertebral resection in the thoracolumbar region assisted by retroperitoneal laparoscopy in a single prone position: first results

PURPOSE

To describe the technique and review the oncological and surgical results of the En Bloc resection assisted by retroperitoneal laparoscopy in a single prone position for tumors in the thoracolumbar region.

METHODS

Monocentric retrospective case study. Procedure was performed in a single prone position by a dual team of spine and thoracovascular surgeons. An endoscopic balloon was inflated in the right retroperitoneal cavity. A plan was developed between the anterior spine and vena cava as well as abdominal aorta with segmental vessels ligation. Structures at risk were safely protected under endoscopy during horizontal or sagittal osteotomies.

RESULTS

From 2021, seven patients aged a median 52 years old (range, 34-67) were included. Involved spinal segments went from T11 to L3. Surgery was aborted in one case due to massive bleeding and ventilating difficulties. There were two partial and four total vertebral resections. Median operating duration and estimated blood loss were 405 min (range, 360-540) and 2.1 L (range, 1.2-19), respectively. Postoperative complications consisted of 1 urinary infection; 1 transient urinary retention; 1 posterior wound infection; 1 pneumothorax; 1 persistent partial motor deficit; 1 transient confusion; 1 pulmonary embolism; 1 CSF leak; 1 subdural hematoma; 1 retroperitoneal lymphocele. All margins were uncontaminated. All patients were alive and ambulatory at last follow-up.

CONCLUSION

Early results suggest En Bloc resection assisted by retroperitoneal videoscopy in tumors from T11 to L3/4 disk space is feasible, less invasive and safe. Careful surgical planning and experience in endoscopic vascular surgery are mandatory.

Clinical outcomes following total en bloc spondylectomy for spinal metastases from lung cancer

BACKGROUND

The current guidelines for the treatment of non-small cell lung cancer encourage local curative treatment for selected patients with oligometastases. This study evaluated the surgical results of total en bloc spondylectomy (TES) for isolated spinal metastases originating from lung cancer in carefully selected patients.

METHODS

We retrospectively reviewed 14 patients (7 men and 7 women) who underwent TES for spinal metastases originating from lung cancer between 2000 and 2017. The primary outcome measure was the postoperative overall survival time. The histological types included adenocarcinoma (n = 12), pleomorphic carcinoma (n = 1), and small cell lung carcinoma (SCLC) (n = 1 patient). We assessed postoperative survival using Kaplan-Meier analysis and the log-rank test.

RESULTS

The median postoperative survival time was 83.0 months (6-162 months) in 13 patients with non-small cell lung carcinoma (NSCLC) and 6 months in 1 patient with SCLC. The 3-, 5-, and 10-year overall survival rates in patients with NSCLC were 61.5%, 53.8%, and 15.4%, respectively. Poor postoperative performance status (PS) and Frankel grade, and preoperative irradiation to the vertebrae to be resected were significantly associated with short-term survival after TES in patients with NSCLC (p < 0.05).

CONCLUSIONS

The surgical results of TES for spinal metastases of lung cancer were relatively favorable among carefully selected patients. TES may be indicated for spinal metastases of lung cancer in patients with controlled primary lung cancer, NSCLC histology, prospect of good postoperative PS, and preferably no irradiation to the target vertebrae.

Complications and local recurrence of chondrosarcoma and chordoma treated by total tumor resection in thoracic and lumbar spine

BACKGROUND

En bloc resection of spinal tumors is challenging and associated with a high incidence of complications; however, it offers the potential to reduce the risk of recurrence when a wide margin is achieved. This research aims to investigate the safety and efficacy of en bloc resection in treating thoracic and lumbar chondrosarcoma/chordoma.

METHODS

Data from patients diagnosed with chondrosarcoma and chordoma in the thoracic or lumbar region, who underwent total en bloc or piecemeal resection at our institution over a 7-year period, were collected and regularly followed up. The study analyzed overall perioperative complications and compared differences in complications and local tumor recurrence between the two surgical methods.

RESULTS

Seventeen patients were included, comprising 12 with chondrosarcoma and 5 with chordoma. Among them, 5 cases underwent intralesional piecemeal resection, while the remaining 12 underwent planned en bloc resection. The average surgical time was 684 min (sd = 287), and the mean estimated blood loss was 2300 ml (sd = 1599). Thirty-five complications were recorded, with an average of 2.06 perioperative complications per patient. 82% of patients (14/17) experienced at least one perioperative complication, and major complications occurred in 64.7% (11/17). Five patients had local recurrence during the follow-up, with a mean recurrence time of 16.2 months (sd = 7.2) and a median recurrence time of 20 months (IQR = 12.5). Hospital stays, operation time, blood loss, and complication rates did not significantly differ between the two surgical methods. The local recurrence rate after en bloc resection was lower than piecemeal resection, although not statistically significant (P = 0.067).

CONCLUSIONS

The complication rates between the two surgical procedures were similar. Considering safety and local tumor control, en bloc resection is recommended as the primary choice for patients with chondrosarcoma/chordoma in the thoracic and lumbar regions who are eligible for this treatment.

A novel prognostic scoring system combining the revised Tokuhashi score and the New England spinal metastasis score for preoperative evaluation of spinal metastases

Purpose

Numerous scoring systems have been developed in order to determine the prognosis of spinal metastases. Predicting as accurately as possible the life expectancy of patients with spinal metastatic disease is very important, as it's the decisive factor in selecting the optimal treatment for the patient. The Revised Tokuhashi score (RTS) and the New England Spinal Metastasis score (NESMS) are popular scoring systems used to determine the optimal treatment modality. However, they sometimes provide conflicting results. We propose a novel prognostic scoring system, which combines the RTS and NESMS scores in order to predict with greater accuracy the prognosis.

Methods

We retrospectively reviewed the data of 64 patients with spinal metastasis enrolled between 2012 and 2021 in the Department of Orthopedic Surgery-Spine, Hôpital Maisonneuve-Rosemont, Montréal, Que. The new score per patient was calculated as a combination of the RTS of each patient and the patient's corresponding NESMS. The new score was then compared to the actual patient survival period and divided into 3 categories: Low, Moderate and Good prognosis. We then compared the accuracy of our new score to RTS.

Results

In the Low Prognosis group, the reliability of predicting the prognosis was 51.9% in 27 patients. In the Moderate Prognosis group, the reliability of predicting the prognosis was 95.8% in 24 patients. In the Good Prognosis group, the reliability of predicting the prognosis was 100% in 13 patients. Our new score was found more accurate than RTS as the R2 parameter corresponding to the new score was significantly increased compared to the same parameter corresponding to the RTS score indicating a higher percentage of survival predictability for the new score as compared to the RTS score.

Conclusion

This study demonstrates that a new prognostic scoring system, which would combine the RTS and the NESMS, is promising in providing an improved accuracy for predicting the actual patient survival, especially for the moderate and good prognosis patients. An appropriate prospective investigation with a larger sample size should be conducted in order to further investigate the validity of this novel scoring system and its overall predictive value.

Clinical and radiological outcomes of n-HA/PA66 cages in anterior spine reconstruction following total en bloc spondylectomy for tumors

Objective

This retrospective monocentric study was conducted to evaluate the clinical and radiological outcomes of the nano-hydroxyapatite/polyamide66 (n-HA/PA66) cage in reconstructing the anterior column of the spine following total en bloc spondylectomy (TES).

Methods

A cohort of 24 patients, 20 diagnosed with primary malignant tumors and 4 with metastatic malignancies, was selected based on specific inclusion criteria. All were subjected to TES and anterior column reconstruction with the n-HA/PA66 cage from January 2013 to July 2023 at a single institution. Pre-operative embolization was performed on all patients. Documented factors included operation duration, intraoperative blood loss, length of hospital stay, treatment history, and involved level. Mechanical complications and radiological parameters such as the local kyphotic angle (LKA), anterior vertebral height (AVH), posterior vertebral height (PVH), cage subsidence, and bone fusion time were evaluated. Quality of life and neurological function were gauged using tools like the Visual Analog Scale (VAS), Eastern Cooperative Oncology Group (ECOG) performance score, Karnofsky Performance Score (KPS) scale, and American Spinal Injury Association (ASIA) grading.

Results

All patients were followed up for 12-127 months, with an average period of 39.71 months. An average operation time of approximately 8.57 h and a blood loss volume of about 1,384 ml were recorded. No instances of tumor recurrence or multiple organ metastases were reported, though recurrence was detected in 2 living patients. Solid fusion was achieved in all patients at a mean time of 6.76 ± 0.69 months. Cage breakage or migration was not observed. Subsidence into the adjacent vertebral bodies was identified in 3 patients but was deemed clinically irrelevant. Significant improvements in VAS, ECOG performance score, KPS scale, and ASIA scores were noted from pre- to post-surgery (P < 0.05). A marked enhancement in the AVH was observed from before surgery to immediately after (P < 0.05). LKA, AVH, and PVH values between postoperative and final follow-up showed no significant variance (P > 0.05).

Conclusion

The integration of TES and the n-HA/PA66 cage was found to yield promising clinical and radiological outcomes in anterior column spine reconstruction. The use of this material did not hinder oncological care, including the provision of adjuvant treatments (chemo/radiotherapy), ultimately contributing to the enhanced long-term quality of life for spinal tumor patients.

Comparison of anterior column reconstruction techniques after en bloc spondylectomy: a finite element study

Total en bloc spondylectomy (TES) effectively treats spinal tumors. The surgery requires a vertebral body replacement (VBR), for which several solutions were developed, whereas the biomechanical differences between these devices still need to be completely understood. This study aimed to compare a femur graft, a polyetheretherketone implant (PEEK-IMP-C), a titan mesh cage (MESH-C), and a polymethylmethacrylate replacement (PMMA-C) using a finite element model of the lumbar spine after a TES of L3. Several biomechanical parameters (rotational stiffness, segmental range of motion (ROM), and von Mises stress) were assessed to compare the VBRs. All models provided adequate initial stability by increasing the rotational stiffness and decreasing the ROM between L2 and L4. The PMMA-C had the highest stiffness for flexion-extension, lateral bending, and axial rotation (215%, 216%, and 170% of intact model), and it had the lowest segmental ROM in the instrumented segment (0.2°, 0.5°, and 0.7°, respectively). Maximum endplate stress was similar for PMMA-C and PEEK-IMP-C but lower for both compared to MESH-C across all loading directions. These results suggest that PMMA-C had similar or better primary spinal stability than other VBRs, which may be related to the larger contact surface and the potential to adapt to the patient's anatomy.

The application of 3D-printed auto-stable artificial vertebral body in en bloc resection and reconstruction of thoracolumbar metastases

BACKGROUND

Nerve compression symptoms and spinal instability, resulting from spinal metastases, significantly impact the quality of life for patients. A 3D-printed vertebral body is considered an effective approach to reconstruct bone defects following en bloc resection of spinal tumors. The advantage of this method lies in its customized shape and innermost porous structure, which promotes bone ingrowth and leads to reduced postoperative complications.

OBJECTIVE

The purpose of this study is to assess the effectiveness of 3D-printed auto-stable artificial vertebrae in the en bloc resection and reconstruction of thoracolumbar metastases.

METHODS

This study included patients who underwent en bloc resection of thoracolumbar metastases based on the Weinstein-Boriani-Biagini surgical staging system, between January 2019 and April 2021. The patients were divided into two groups: the observation group, which was reconstructed using 3D-printed auto-stable vertebral bodies, and the control group, treated with titanium cages and allograft bone. Evaluation criteria for the patients included assessment of implant subsidence, instrumentation-related complications, VAS score, and Frankel grading of spinal cord injury.

RESULTS

The median follow-up period was 21.8 months (range 12-38 months). Among the patients, 10 received a customized 3D-printed artificial vertebral body, while the remaining 10 received a titanium cage. The observation group showed significantly lower operation time, intraoperative blood loss, and postoperative drainage compared to the control group (P < 0.05). At the final follow-up, the average implant subsidence was 1.8 ± 2.1 mm for the observation group and 5.2 ± 5.1 mm for the control group (P < 0.05). The visual analog scale (VAS) scores were not statistically different between the two groups at preoperative, 24 h, 3 months, and 1 year after the operation (P < 0.05). There were no statistically significant differences in the improvements of spinal cord functions between the two groups.

CONCLUSION

The utilization of a 3D-printed auto-stable artificial vertebra for reconstruction following en bloc resection of thoracolumbar metastases appears to be a viable and dependable choice. The low occurrence of prosthesis subsidence with 3D-printed prostheses can offer immediate and robust stability.

Clinical Outcomes of Total En Bloc Spondylectomy for Previously Irradiated Spinal Metastases: A Retrospective Propensity Score-Matched Comparative Study

This study aimed to investigate the clinical outcomes of total en bloc spondylectomy (TES) for spinal metastases previously treated with radiotherapy (RT). This study enrolled 142 patients who were divided into two groups: those with and those without an RT history. Forty-two patients were selected from each group through propensity score matching, and postoperative complications, local recurrence, and overall survival rates were compared. The incidence of postoperative complications was significantly higher in the group with an RT history than in the group without an RT history (57.1% vs. 35.7%, respectively). The group with an RT history had a higher local recurrence rate than the group without an RT history (1-year rate: 17.5% vs. 0%; 2-year rate: 20.8% vs. 2.9%; 5-year rate: 24.4% vs. 6.9%). The overall postoperative survival tended to be lower in the group with an RT history; however, there was no significant difference between the two groups (2-year survival: 64.3% vs. 66.7%; 5-year survival: 47.3% vs. 57.1%). When planning a TES for irradiated spinal metastases, the risk of postoperative complications and local recurrence should be fully considered.

Metastasectomy of spinal lesions from thyroid carcinomas

Patients with differentiated thyroid carcinomas (DTCs) have a favourable long-term survival. Spinal metastases (SMs) cause a decline in performance status (PS), directly affecting mortality and indirectly preventing the use of systemic therapies. Metastasectomy is indicated, if feasible, as it yields the best local tumour control. Our study aimed to examine the long-term clinical outcomes of metastasectomy for SMs of thyroid carcinomas. We collected data on 22 patients with DTC (16 follicular and six papillary carcinomas) and one patient with medullary carcinoma who underwent complete surgical resection of SMs at our institution between July 1992 and July 2017, with a minimum postoperative follow-up of five years. The cancer-specific survival (CSS) from the first spinal metastasectomy to death or the last follow-up was determined using Kaplan-Meier analysis. Potential factors associated with survival were evaluated using the log-rank test. We analyzed the clinical parameters and outcome data, including pre- and postoperative disability (Eastern Cooperative Oncology Group PS 3), lung and non-spinal bone metastases, and history of radioiodine and kinase inhibitor therapies. Lung and other bone metastases at the time of surgery were observed in ten and eight patients, respectively. Three patients experienced local tumour recurrences at the operated site. The five- and ten-year CSS rates in the 22 patients with DTC were 77% and 52%, respectively. Pre- and postoperative disability and operative site tumour recurrence were identified as risk factors for short postoperative survival. Metastasectomy for resectable SM from DTC yielded favourable results and has the potential to improve survival.

Complications and prognosis of primary thoracic and lumbar giant cell tumors treated by total tumor resection

BACKGROUND

Spinal giant cell tumor (SGCT) is a relatively rare primary tumor. En bloc resection is the preferred surgical procedure for it due to its aggressiveness, meanwhile leading to more complications. We reported the characteristics of perioperative complications and local control of total tumor resection including en bloc resection and piecemeal resection for primary thoracic and lumbar spinal giant cell tumors in a single center over 10 years.

METHODS

This is a retrospective cross-sectional and cohort study. Forty-one consecutive patients with SGCTs who underwent total tumor resection from 2010 to 2020 at our institution and were followed up for at least 24 months were reviewed. Surgery data, complication characteristics and local tumor control were collected and compared by different surgical procedure.

RESULTS

Forty-one patients were included, consisting of 18 males and 23 females, with a mean age of 34.2 years. Thirty-one had thoracic vertebra lesions, and 10 had lumbar vertebra lesions. Thirty-five patients were primary cases, and 6 patients were recurrent cases. Eighteen patients were treated by total en bloc spondylectomy (TES), 12 patients underwent en bloc resection according to WBB surgical system, and 11 patients underwent piecemeal resection. The average surgical time was 498 min, and the mean estimated blood loss was 2145 ml. A total of 58 complications were recorded, and 30 patients (73.2%) had at least one perioperative complication. All patients were followed up after surgery for at least 2 years. A total of 6 cases had postoperative internal fixation failure, and 4 cases presented local tumor recurrence (9.8%).

CONCLUSIONS

Although the surgical technique is difficult and accompanied by a high rate of perioperative complications, en bloc resection can achieve favorable local control in SGCT. When it is too difficult to complete en bloc resection, thoroughly piecemeal resection without residual is also acceptable, given the relatively low recurrence rate.

Axial Axis Metastasis

Axial axis metastasis remains a challenge for surgical as well as other treatment modalities, like chemotherapy, immunotherapy, and radiotherapy. It is unequivocal that surgery provides pain improvements and preservation of neurological status, but this condition remains when associated with radiotherapy and other treatment modalities. In this review, we emphasize the current forms of surgical treatment in the different regions of the spine and pelvis. The evident possibility of percutaneous treatments is related to early or late cases, and in cases in which there are greater risks and instability to conventional surgeries associated with radiotherapy and have been shown to be the appropriate option for local control of metastatic disease.

Characteristics and risk factors of instrumentation failure following total en bloc spondylectomy

AIMS

The aim of this study was to investigate the incidence and characteristics of instrumentation failure (IF) after total en bloc spondylectomy (TES), and to analyze risk factors for IF.

METHODS

The medical records from 136 patients (65 male, 71 female) with a mean age of 52.7 years (14 to 80) who underwent TES were retrospectively reviewed. The mean follow-up period was 101 months (36 to 232). Analyzed factors included incidence of IF, age, sex, BMI, history of chemotherapy or radiotherapy, tumour histology (primary or metastasis; benign or malignant), surgical approach (posterior or combined), tumour location (thoracic or lumbar; junctional or non-junctional), number of resected vertebrae (single or multilevel), anterior resection line (disc-to-disc or intravertebra), type of bone graft (autograft or frozen autograft), cage subsidence (CS), and local alignment (LA). A survival analysis of the instrumentation was performed, and relationships between IF and other factors were investigated using the Cox regression model.

RESULTS

A total of 44 patients (32.4%) developed IF at a median of 31 months (interquartile range 23 to 74) following TES. Most IFs were rod fractures preceded by a mean CS of 6.1 mm (2 to 18) and LA kyphotic enhancement of 10.8° (-1 to 36). IF-free survival rates were 75.8% at five years and 56.9% at ten years. The interval from TES to IF peaked at two to three years postoperatively and continued to occur over a period of time thereafter; the early IF-developing group had greater CS at one month postoperatively (CS1M) and more lumbar TES. CS1M ≥ 3 mm and sole use of frozen autografts were identified as independent risk factors for IF.

CONCLUSION

IF is a common complication following TES. We have demonstrated that robust spinal reconstruction preventing CS, and high-quality bone grafting are necessary for successful reconstruction.Cite this article: Bone Joint J 2023;105-B(2):172-179.

Clinical results of total en bloc spondylectomy using a single posterior approach in spinal metastasis patients: Experiences from Thailand

AIM

To demonstrate a single posterior approach, total en bloc spondylectomy (TES) could be performed safely without preoperative embolization in spinal metastasis patients.

MATERIALS AND METHODS

Thirteen solitary spinal metastasis patients (five males) underwent single posterior approach TES at the thoracolumbar spine without preoperative embolization from January 2018 to January 2020. The primary sites were the breast (n = 4), hepatocellular carcinoma (n = 2), colon (n = 2), and others (n = 5). All patients underwent single posterior TES. The Eastern Cooperative Oncology Group, Frankel neurological status, operative time and blood loss, and any complications were all recorded. The patients were regularly followed-up with radiography, computed tomography, and magnetic resonance imaging to detect any local recurrences.

RESULTS

The mean operative time was 354.6 min, and the mean operative blood loss was 2134.62 ml. None of the patients experienced any perioperative complications. Within the follow-up period (3-24 months), no local recurrences were detected. Two patients (15.38%) were found to have distant metastasis to adjacent and remote vertebrae. Three patients were lost to follow-up, and three patients died of disease. Six patients showed an improved ECOG functional status by at least one grade. Four of Frankel A patients improved their neurological status by at least one grade.

CONCLUSION

Even without embolization, single posterior TES at the thoracolumbar spine is safe and effective for short-term local control in solitary spinal metastasis. However, TES cannot prevent distant metastasis. Longer-term follow-up studies will be able to further identify the benefits of TES for the long-term local control of diseases.

A Modified Spinal Reconstruction Method Reduces Instrumentation Failure in Total En Bloc Spondylectomy for Spinal Tumors

Introduction

Long-term spinal stability after total en bloc spondylectomy (TES) is challenging. The aim of this study was to examine whether the new method could reduce the incidence of instrumentation failure (IF).

Methods

We retrospectively compared 116 patients with spinal tumors who underwent TES between 2010 and 2019 and were followed up for >1 year. IF, cage subsidence, and complications were evaluated. Propensity score matching between conventional and new method groups was performed for age, sex, body mass index, preoperative radiotherapy, number of resected vertebrae, number of instrumented vertebrae, tumor level, and follow-up period. There were 25 cases each in the conventional and new method groups. The conventional method used a titanium mesh cage for anterior reconstruction and 5.5-mm-diameter titanium alloy rods for posterior fixation. The new method used a more robust cage for anterior reconstruction, bone grafting was performed around the cage, and 6.0-mm-diameter cobalt chromium rods were used for posterior fixation. We compared the incidence of IF and cage subsidence after TES between the conventional and new method groups.

Results

While 5 out of 25 patients (20.0%) in the conventional method group experienced IF, none from the new method group experienced IF. Three-year implant survival rates were 87.3% in the conventional and 100% in the new method groups. The new method group had a significantly higher implant survival rate (p<0.01). Cage subsidence was observed in 11 of 25 (44/0%) patients in the conventional method and 1 of 25 (4.0%; significantly lower, p<0.05) in the new method group.

Conclusions

The new reconstruction method significantly reduced IF incidence in patients with TES.

Prognostic Factors for Bone Survival and Functional Outcomes in Patients With Breast Cancer Spine Metastases

According to the Global Cancer Statistics 2020 report, breast cancer is the most commonly diagnosed cancer worldwide. Patients with mammary cancer live longer due to the continuous optimization of chemotherapy, targeted drugs, and hormone therapy, which will inevitably lead to an increase in the prevalence of metastatic bone tumors. Bone metastasis affects approximately 8% of patients with mammary cancer, with the spine being the most common site. Metastatic neoplasms can invade the centrum and its attachments, leading to local pain, spinal instability, vertebral pathological fractures, spinal cord compression, impaired neurological function, and paralysis, ultimately reducing the quality of life. Multidisciplinary and personalized management using analgesic drugs, endocrine therapy, corticosteroid therapy, chemotherapy, bisphosphonates, immunotherapy, targeted drugs, radiotherapy, and surgery has been advocated for the treatment of spinal metastases. Multiple paradigms and systems have been proposed to determine suitable treatments. In the early stages, the occurrence of metastasis indicates a terminal stage of the tumor process in patients with malignant tumors, implying that their lifespan is limited. As a result, the choice of treatment is heavily influenced by longevity. However, with the development of treatment methods, the lifespan of patients with tumors has considerably increased in recent years. This leads to the choice of patient's treatment, which depends not only on the patient's survival, but also on the radiotherapy or postoperative functional outcomes. Nevertheless, they fall short of determining the variables that affect survival and functional outcomes in histology-specific subgroups of breast cancer. To accurately predict the bone survival and functional outcomes of patients with breast cancer spine metastases a review of prognostic factors was performed.

One-stage En bloc resection of thoracic spinal chondrosarcoma with huge paravertebral mass through the single posterior approach by dissociate longissimus thoracis

Study design

Retrospective case series.

Objective

To describe the technique details and therapeutic outcomes of 3-D printing model-guided en bloc resection of chondrosarcoma (CHS) with huge paravertebral mass via the combined posterior median and Wiltse approach.

Summary of background data

Total en bloc spondylectomy (TES) technique is conventionally based on the single posterior approach or combined anterior-posterior approach. However, the single posterior approach imposes a high technical demand on the surgeon due to the narrow field of vision, limited surgical space and the delicate spinal cord, while the combined anterior-posterior approach not only requires greater patient tolerance but is time consuming and runs the risk of more blood loss and injury to the visceral pleura and large blood vessels during surgery. In addition, it is difficult to completely remove the thoracic CHS with paravertebral mass through simple en bloc resection when it involves the aorta, vena cava, costa and lung.

Material and methods

Between August 2010 and January 2016, we performed a retrospective study to evaluate the clinical characteristics and outcomes of en bloc resection of thoracic spinal CHS with paravertebral mass through the combined posterior median and Wiltse approach. Postoperative recurrence-free survival (RFS) and overall survival (OS) were estimated by the Kaplan-Meier method. P values less than 0.05 were considered statistically significant.

Results

Altogether 15 patients received en bloc resection of thoracic spinal CHS with paravertebral mass through the combined posterior median and Wiltse approach. The mean age of these patients was 37.0 ± 12.8 years (median 36; range 15–64). This combination approach provided more extensive exposure and wider marginal resection of the tumor within a mean operation duration of 288 ± 96 min (median 280; range 140–480) and mean intraoperative blood loss of 1,966 ± 830 ml (median 2,000; range 300–3,000). Of the 15 patients, 5 experienced local recurrence of the disease; the mean time from surgery to recurrence was 22 ± 9.85 months (median 17, range 13–35). RFS in patients with recurrent CHS was significantly lower than that in patients with primary CHS on admission (p = 0.05).

Conclusions

The combined posterior median and Wiltse approach is a technically viable option for en bloc resection of thoracic spinal CHS with huge paravertebral mass, and can give a favorable local control of CHS.

Level of evidence

Level V.

Medium to Long-Term Clinical Outcomes of Spinal Metastasectomy

The prolonged survival of metastatic cancer patients highlights the importance of the local control of spinal metastases, which reduce patient performance status. This retrospective study examined the medium to long-term outcomes of spinal metastasectomy by evaluating 124 patients who underwent metastasectomy for isolated spinal metastases (2006-2018) with a postoperative follow-up for a minimum of 3 years. The findings present information on patient demographics (i.e., performance status, location of non-spinal metastases, and history of systemic therapy) and postoperative outcomes, including perioperative complications, disease progression of non-operated metastases, and additional excisional surgeries. Additionally, postoperative survival, local tumor control in the operated spine, and maintenance of spinal reconstruction without instrumentation failure were determined using Kaplan-Meier analyses. The primary malignancy was kidney and thyroid cancer in 51 and 14 patients, respectively, low-grade sarcoma and lung cancer in 13 patients, breast cancer in 12 patients, and other malignancies in 21 patients. The 3-year and 5-year survival rates were 70% and 60%, respectively. We found that patients with thyroid cancer had the best survival results, with local tumor recurrence and instrumentation failure at 10% and 22%, respectively. These findings suggest that for certain patients with isolated and removable spine metastases, metastasectomy can improve function and survival.

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.

Quantified CIN Score From Cell-free DNA as a Novel Noninvasive Predictor of Survival in Patients With Spinal Metastasis

Purpose: Most currently available scores for survival prediction of patients with bone metastasis lack accuracy. In this study, we present a novel quantified CIN (Chromosome Instability) score modeled from cfDNA copy number variation (CNV) for survival prediction. Experimental Design: Plasma samples collected from 67 patients with bone metastases from 11 different cancer types between November 2015 and May 2016 were sent through low-coverage whole genome sequencing followed by CIN computation to make a correlation analysis between the CIN score and survival prognosis. The results were validated in an independent cohort of 213 patients. Results: During the median follow-up period of 598 (95% CI 364-832) days until December 25, 2018, 124 (44.3%) of the total 280 patients died. Analysis of the discovery dataset showed that CIN score = 12 was the optimal CIN cutoff. Validation dataset showed that CIN was elevated (score ≥12) in 87 (40.8%) patients, including 5 (5.75%) with head and neck cancer, 11 (12.6%) with liver and gallbladder cancer, 11 (12.6%) with cancer from unidentified sites, 21 (24.1%) with lung cancer, 7 (8.05%) with breast cancer, 4 (4.60%) with thyroid cancer, 6 (6.90%) with colorectal cancer, 4 (4.60%) with kidney cancer, 2 (2.30%) with prostate cancer, and 16 (18.4%) with other types of cancer. Further analysis showed that patients with elevated CIN were associated with worse survival (p < 0.001). For patients with low Tokuhashi score (≤8) who had predictive survival of less than 6 months, the CIN score was able to distinguish patients with a median overall survival (OS) of 443 days (95% CI 301-585) from those with a median OS of 258 days (95% CI 184-332). Conclusion: CNV examination in bone metastatic cancer from cfDNA is superior to the traditional predictive model in that it provides a noninvasive and objective method of monitoring the survival of patients with spine metastasis.

Tailored surgery on aggressive osteoblastoma involving the cervicothoracic junction: an oncological and spinal stability long-term follow-up

INTRODUCTION

Aggressive osteoblastoma (AO) represents a rare tumor with borderline features between benign osteoblastoma and osteosarcoma. Having a local aggressive behavior without metastasizing attitude, radical excision is a mainstay treatment. Conversely, spine fusion technique is still debated. We report a rare case of cervicothoracic junction (CTJ) AO and the tailored decision-making process to choose the best treatment.

CASE PRESENTATION

A 34-year-old man complaining of neck pain was admitted to our department. Cervicothoracic MRI revealed a well-circumscribed lesion involving C7 left lamina with cortical erosion and mild spinal canal invasion. Additionally, STIR sequences exhibited a bright signal spreading through the posterior third of the C7 and T1 vertebrae which on T1-weighted and T2-weighted sequences appeared isointense and hyperintense, respectively. Therefore, the patient underwent a C7 laminotomy. Histology revealed an aggressive variant of osteoblastoma. Therefore, tumor was classified as AO and surgical management was reconsidered. A combined anterior and posterior approach was recommended to reach oncological radicality and spinal stability. At 6-years follow-up, patient remained neurologically intact without signs of recurrence and/or of instability.

DISCUSSION

Due to its rarity and mimicking features, diagnosis of AO results challenging. Due to its aggressive behavior, radical surgery is the mainstay treatment. Conversely, the most suitable fusion technique is still debated. A proper surgical management should be focused on oncological radicality to guarantee the total tumoral removal avoiding progression or recurrences. Similarly, a proper evaluation of the long-term spinal balance should be assessed to avoid developing of spinal deformities or instrumentation failures.

Surgical Metastasectomy in the Spine: A Review Article

BACKGROUND

The use of surgical metastasectomy (SM) has increased across cancer types in recent decades despite the increasing efficacy of modern systemic treatment modalities. Symptomatic spinal metastases severely compromise patients' performance status. However, as spinal SM is a complex surgery with potentially significant complications, it is not considered the treatment of choice.

METHODS

We reviewed the articles on SM in several primary cancers with different types of metastatic lesions and extracted the data from relevant articles to provide a comprehensive review including the surgical techniques, indications, reported outcomes, and future prospects of SM in spinal metastases.

RESULTS

Total en bloc spondylectomy (TES) is a method of spinal SM associated with a lower risk of tumor recurrence and complications. Intralesional transpedicular osteotomy using a fine threadwire saw allows prevention of spinal cord and nerve root injuries. Spinal SM is considered suitable for patients with controlled primary disease having no evidence of disseminated extraspinal metastases, a completely resectable solitary lesion in the spine, and adequate cardiopulmonary reserve to tolerate the surgery. Metastatic lesions from kidney and thyroid cancers have been reported as the best candidates for spinal SM. Although data about spinal SM are limited, the reported outcomes are favorable with acceptable local recurrence rates in long-term follow-up.

CONCLUSION

In patients with isolated resectable spinal metastases, complete SM including TES is a useful option as it can improve function and survival. However, appropriate patient selection and surgical feasibility remain the most important aspects of management.

IMPLICATIONS FOR PRACTICE

Surgical metastasectomy for spinal metastases may be a potentially curative treatment option with a low risk of local recurrence and lead to prolonged long-term survival if appropriate patients are selected and if the surgery is carried out by experienced surgeons in high-volume centers.

Clinical outcomes and prognostic factors following the surgical resection of renal cell carcinoma spinal metastases

The efficacy of surgical resection in metastatic renal cell carcinoma is an active and important research field in the postcytokine era. Bone metastases, especially in the spine, compromise patient performance status. Metastasectomy is indicated, if feasible, because it helps to achieve the best clinical outcomes possible compared with other treatments. This study examined the postoperative survival and prognostic factors in patients who underwent metastasectomy of spinal lesions. The retrospective study included 65 consecutive patients with metastatic renal cell carcinomas who were operated on by spinal metastasectomy between 1995 and 2017 at our institution. The cancer‐specific survival times from the first spinal metastasectomy to death or the last follow‐up (≥3 years) were determined using Kaplan‐Meier analysis. Potential factors influencing survival were analyzed using Cox proportional hazard models. Planned surgical resection of all the spine tumors was achieved in all patients. Of these, 38 had complete metastasectomy of all visible metastases, including extraspinal lesions. In all patients, the estimated median cancer‐specific survival time was 100 months. The 3‐, 5‐, and 10‐year cancer‐specific survival rates were 77%, 62%, and 48%, respectively. The survival times after spinal metastasectomy were similar in both cytokine and postcytokine groups. In multivariate analyses, postoperative disability, the coexistence of liver metastases, multiple spinal metastases, and incomplete metastasectomy were significant risk factors associated with short‐term survival. Complete metastasectomy, including extraspinal metastases, was associated with improved cancer‐specific survival. Proper patient selection and complete metastasectomy provide a better prognosis in metastatic renal cell carcinoma patients.

Biomechanics of artificial pedicle fixation in a 3D-printed prosthesis after total en bloc spondylectomy: a finite element analysis

Background

This study compared the biomechanics of artificial pedicle fixation in spine reconstruction with a 3-dimensional (3D)-printed prosthesis after total en bloc spondylectomy (TES) by finite element analysis.

Methods

A thoracolumbar (T10–L2) finite element model was developed and validated. Two models of T12 TES were established in combination with different fixation methods: Model A consisted of long-segment posterior fixation (T10/11, L1/2) + 3D-printed prosthesis; and Model B consisted of Model A + two artificial pedicle fixation screws. The models were evaluated with an applied of 7.5 N·m and axial force of 200 N. We recorded and analyzed the following: (1) stiffness of the two fixation systems, (2) hardware stress in the two fixation systems, and (3) stress on the endplate adjacent to the 3D-printed prosthesis.

Results

The fixation strength of Model B was enhanced by the screws in the artificial pedicle, which was mainly manifested as an improvement in rotational stability. The stress transmission of the artificial pedicle fixation screws reduced the stress on the posterior rods and endplate adjacent to the 3D-printed prosthesis in all directions of motion, especially in rotation.

Conclusions

After TES, the posterior long-segment fixation combined with the anterior 3D printed prosthesis could maintain postoperative spinal stability, but adding artificial pedicle fixation increased the stability of the fixation system and reduced the risk of prosthesis subsidence and instrumentation failure.

The most appropriate titanium mesh cage size for anterior spinal reconstruction after single-level lumbar total en bloc spondylectomy: a finite element analysis and cadaveric validation study

Purpose

There is little information available regarding the cage diameter that can provide the most rigid construct reconstruction after total en bloc spondylectomy (TES). The aim of this study was thus to determine the most appropriate titanium mesh cage diameter for reconstruction after spondylectomy.

Methods

A finite element model of the single level lumbar TES was created. Six models of titanium mesh cage with diameters of 1/3, 1/2, 2/3, 3/4, 4/5 of the caudad adjacent vertebra, and 1/1 of the cephalad vertebra were tested for construct stiffness. The peak von Mises stress (MPa) at the failure point and the site of failure were measured as outcomes. A cadaveric validation study also conducted to validate the finite element model.

Results

For axial loading, the maximum stress points were at the titanium mesh cage, with maximum stress of 44,598 MPa, 23,505 MPa, 23,778 MPa, and 16,598 MPa, 10,172 MPa, 10,805 MPa in the 1/3, 1/2, 2/3, 3/4, 4/5, and 1/1 diameter model, respectively. For torsional load, the maximum stress point in each of the cages was identified at the rod area of the spondylectomy site, with maximum stress of 390.9 MPa (failed at 4459 cycles), 141.35 MPa, 70.098 MPa, and 88.972 MPa, 42.249 MPa, 15.827 MPa, respectively. A cadaveric validation study results were coincided with the finite element model results.

Conclusion

The most appropriate mesh cage diameter for reconstruction is 1/1 the diameter of the lower endplate of the adjacent cephalad vertebra, due to its ability to withstand both axial and torsional stress. According to the difficulty of large size cage insertion, a cage diameter of more than half of the upper endplate of the caudad vertebrae is acceptable in term of withstand stress. A cage diameter of 1/3 is unacceptable for reconstruction after total en bloc spondylectomy.

Chordoma of the sacrum and mobile spine: a narrative review

Chordoma is a notochord-derived primary tumor of the skull base and vertebral column known to affect 0.08 to 0.5 per 100,000 persons worldwide. Patients commonly present with mechanical, midline pain with or without radicular features secondary to nerve root compression. Management of these lesions has classically revolved around oncologic resection, defined by en bloc resection of the lesion with negative margins as this was found to significantly improve both local control and overall survival. With advancement in radiation modalities, namely the increased availability of focused photon therapy and proton beam radiation, high-dose (>50 Gy) neoadjuvant or adjuvant radiotherapy is also becoming a standard of care. At present chemotherapy does not appear to have a role, but ongoing investigations into the ontogeny and molecular pathophysiology of chordoma promise to identify therapeutic targets that may further alter this paradigm. In this narrative review we describe the epidemiology, histopathology, diagnosis, and treatment of chordoma.

Total en bloc spondylectomy combined with the satellite rod technique for spinal tumors

Background

Instrumentation failure (IF) is a common complication after total en bloc spondylectomy (TES) in spinal tumors. This study aims to evaluate the clinical outcomes of TES combined with the satellite rod technique for the treatment of primary and metastatic spinal tumors.

Methods

The clinical data of 15 consecutively treated patients with spinal tumors who underwent TES combined with the satellite rod technique by a single posterior approach from June 2015 to September 2018 were analyzed retrospectively. Radiographic parameters including the local kyphotic angle (LKA), anterior vertebral height (AVH), posterior vertebral height (PVH), and intervertebral titanium mesh cage height (ITMCH) were assessed preoperatively, postoperatively, and at the final follow-up. The visual analog scale (VAS), Oswestry Disability Index (ODI), and American Spinal Injury Association (ASIA) scale were used to assess quality of life and neurological function. The operative duration, volume of blood loss, and complications were also recorded.

Results

The mean operation time and volume of blood loss were 361.7 min and 2816.7 mL, respectively. During an average follow-up of 31.1 months, 2 patients died of tumor recurrence and multiple organ metastases, while recurrence was not found in any other patients. Solid fusion was achieved in all but one patient, and no implant-related complications occurred during the follow-up. The VAS, ODI, and ASIA scores significantly improved from before to after surgery (P < 0.05). The LKA, AVH, and PVH significantly improved from before to immediately after surgery and to the final follow-up (P < 0.05), and the postoperative and final follow-up values did not significantly differ (P > 0.05).

Conclusions

TES combined with the satellite rod technique can yield strong three-dimensional fixation and reduce the occurrence of rod breakage, thereby improving the long-term quality of life of patients with spinal tumors.

Anterior Spinal Artery Syndrome Occurring after One Level Segmental Artery Ligation during Spinal Surgery

In treating the ventral pathology of spine, ligating the segmental vessels is sometimes necessary. This may cause spinal cord ischemia, and concerns of neurologic injury have been presented. However, spinal cord ischemic injury after sacrificing segmental vessels during spine surgery is very rare. Reports of this have been scarce in the literature and most of these complications occur after multi-level segmental vessel ligation. Here we report a case of a patient with postoperative anterior spinal artery syndrome, which occurred after ligating one level segmental vessels during spinal surgery for a T8 vertebral pathologic fracture. Despite its rarity, the risk of spinal cord ischemic injury after segmental vessel ligation is certainly present. Surgeons must keep in mind such risk, and surgery should be planned under a careful risk-benefit consideration.

Revision surgery for instrumentation failure after total en bloc spondylectomy: a retrospective case series

Background

There have been several reports of instrumentation failure after three-column resections such as total en bloc spondylectomy (TES) for spinal tumors; however, clinical outcomes of revision surgery for instrumentation failure after TES are seldom reported. Therefore, this study assessed the clinical outcomes of revision surgery for instrumentation failure after TES.

Methods

This study employed a retrospective case series in a single center and included 61 patients with spinal tumors who underwent TES between 2010 and 2015 and were followed up for > 2 years. Instrumentation failure rate, back pain, neurological deterioration, ambulatory status, operation time, blood loss, complications, bone fusion after revision surgery, and re-instrumentation failure were assessed. Data were collected on back pain, neurological deterioration, ambulatory status, and management for patients with instrumentation failure, and we documented radiological bone fusion and re-instrumentation failure in cases followed up for > 2 years after revision surgery.

Results

Of the 61 patients, 26 (42.6%) experienced instrumentation failure at an average of 32 (range, 11–92) months after TES. Of these, 23 underwent revision surgery. The average operation time and intraoperative blood loss were 204 min and 97 ml, respectively. Including the six patients who were unable to walk after instrumentation failure, all patients were able to walk after revision surgery. Perioperative complications of reoperation were surgical site infection (n = 2) and delayed wound healing (n = 1). At the final follow-up, bone fusion was observed in all patients. No re-instrumentation failure was recorded.

Conclusion

Bone fusion was achieved by revision surgery using the posterior approach alone.

Surgical Treatment Outcomes of Spinal Metastases of Nasopharyngeal Carcinoma: The First Report of 30 Patients from a Single Center

Background

Studies focused on surgical interventions of spinal metastases of nasopharyngeal carcinoma (SMNPC) are blank.

Methods

Patients with SMNPC who received surgical treatment in our center between 2005 and 2017 were included. Univariate and multivariate analysis of various clinical characteristics and operation-related data were analyzed to identify the independent factors that affected prognosis. Factors with P values of 0.1 or less were subjected to multivariate Cox regression analysis. P values of 0.05 or less were considered statistically significant.

Results

A total of 30 patients with SMNPC treated with surgery were included. The thoracic spine was the most frequently involved site. The patients in this series achieved good overall survival (OS, 20.26 months) with limited perioperative complications. The univariate analysis suggested that preoperative Karnofsky performance scale, number of spinal metastases, number of visceral metastases, preoperative Frankel score, surgical resection mode and Ki 67 were potential prognostic factors. In the multivariate analyses, number of visceral metastases, preoperative Frankel score and resection mode were found to be independent prognostic factors.

Conclusion

This is the first study focusing on surgical outcomes in SMNPC. The thoracic spine was the most frequently involved site of SMNPC. Preoperative Frankel score, number of visceral metastasis and surgical resection mode were independent prognostic factors for SMNPC. Combined with adjuvant therapies, surgical interventions should be recommended early when necessary.

A finite element analysis on comparing the stability of different posterior fixation methods for thoracic total en bloc spondylectomy

Objective

To compare the spinal stability with different fixation methods after thoracic TES using finite element analysis

Methods

The spinal finite element model was established from a healthy volunteer, and the validity was verified. The models of T8 thoracic total en bloc spondylectomy (TES) with and without artificial vertebral body were established combination with different fixation methods: the first was long segment fixation with fixed segments T5–7, T9–11; the second was short segment fixation with fixed segments T6–7, T9–10; the third was modified short segment with a pair of vertebral body screws on T7 and T9 added on the basis of short segment fixation. The motions of each model in standing state were simulated in software. The range of motion (ROM) and internal fixation stress changes were analyzed.

Results

When anterior support was effective, the three fixation methods could effectively maintain the stability of the spine. However, when anterior support failed, the ROM of the long segment fixation group and the short segment fixation group in the flexion-extension directions was significantly higher than that of when the anterior support existed, while the modified short segment fixation group had no significant changes. Meanwhile, the stress of internal fixation in the long segment fixation group and the short segment fixation group were greatly increased. However, there were no significant changes in modified short segment fixation group.

Conclusion

After TES, the presence of the thoracic cage gives partial anterior stabilization. When the anterior support failed, the modified short segment fixation method can provide better stability.

Median Sacral Artery Rupture as a Complication of Posterior-Only Approach of L4 Total En Bloc Spondilectomy: A Case Report

CASE

A 6-year-old patient with Ewing sarcoma at L4 who was treated with total en bloc spondilectomy (TES) through a posterior-only approach. During the dissection of the anterior L4 body, there was uncontrollable bleeding from an unknown origin, which needed packing, massive transfusion, and urgent laparotomy. A median sacral artery (MSA) rupture was identified as the cause of this massive bleeding. Eventually, the patient was successfully stabilized.

CONCLUSIONS

To our knowledge, this is the first reported intraoperative bleeding of the MSA related to a lumbar TES through posterior-only approach. This life-threatening complication should be considered when planning for this type of surgery.

Reducing Surgical Site Infections in Spine Tumor Surgery: A Comparison of Three Methods

STUDY DESIGN

Case control series.

OBJECTIVE

The aim of this study was to evaluate and compare the effectiveness of methods to decrease surgical site infections (SSIs) following spine tumor surgery.

SUMMARY OF BACKGROUND DATA

With the aging population of the United States, the prevalence of cancer and associated metastatic spine disease is increasing. The most common complication of spine tumor surgery is SSI.

METHODS

This a single-institution case-control series of patients undergoing spine tumor surgery from June 2003 to October 2018. Patients were grouped into the following groups: Betadine irrigation and intrawound vancomycin powder (BIVP), intrawound vancomycin powder only (IVP), and patients receiving neither (NONE). The primary outcome was SSIs/wound complications.

RESULTS

One hundred fifty-one spine tumor patients undergoing 174 procedures meeting our inclusion criteria were identified. The BIVP group had 60 patients (73 procedures); the IVP group had 46 patients (47 procedures); and the NONE group had 45 patients (54 procedures). The overall infection rate was 8.6% of all procedures (15/174) and 9.9% (15/151) of all patients. Bivariate analysis comparing patients with and without infections noted the patients with SSIs had significantly higher rates of preoperative radiation treatment (53.3% in infection group vs. 25.5% in noninfection group), P = 0.02. Patients undergoing procedures in the BIVP group had a significantly lower rate of infections (2.7%) than the patients in the IVP (12.8%) and NONE (13%) groups, P = 0.04. Stepwise regression analysis was used to evaluate further factors associated with SSIs. Elevated BMI was significantly associated with SSIs in the model [P = 0.02, odds ratio (OR) 1.14]. BIVP was also protective against infections as compared to the IVP and NONE groups, P = 0.02, OR 0.02.

CONCLUSION

BIVP led to a significant decrease in SSI rates following spine tumor surgery. Administration of BIVP is not time consuming and decreased SSI rates.

LEVEL OF EVIDENCE

3.

Risk Factors for Instrumentation Failure After Total En Bloc Spondylectomy of Thoracic and Lumbar Spine Tumors Using Titanium Mesh Cage for Anterior Reconstruction

OBJECTIVE

The present study investigated the risk factors for instrumentation failure (IF) after total en bloc spondylectomy (TES) of thoracic and lumbar spine tumors using a titanium mesh cage (TMC) for anterior reconstruction.

METHODS

The data from patients who had undergone TES for thoracic and lumbar spine tumors in our institution were retrospectively reviewed. Anterior reconstruction was performed using a TMC filled with morcelized allograft or morcelized autograft. Posterior reconstruction was performed using pedicle fixation. Survival analysis from TES to IF was conducted. The Kaplan-Meier method was used for univariate analysis. Factors of statistical significance were included in the multivariate analysis using Cox regression analysis.

RESULTS

A total of 30 patients (20 men and 10 women), with a mean age of 37.1 ± 14.3 years (range, 14-65 years) were included. The mean follow-up period was 41.8 ± 21.3 months (range, 13-120 months). Bone fusion was achieved in 23 patients (76.7%). IF occurred in 8 patients. The mean interval from TES to the first IF was 31.8 ± 15.1 months (range, 13-64 months). On univariable analysis, a body mass index >28 kg/m², perioperative radiotherapy, and the TMC in an oblique position were associated with IF. On multivariable analysis, these 3 factors were entered into the Cox regression model and were also significant.

CONCLUSIONS

The use of TES can achieve durable oncological control. However, IF, a not uncommon late complication that leads to reoperation, should be a cause for concern. We found perioperative radiotherapy, a TMC in an oblique position, and a body mass index >28 kg/m² were significant predictive factors for IF.

Modified score based on revised Tokuhashi score is needed for the determination of surgical intervention in patients with lung cancer metastases to the spine

BACKGROUND

Revised Tokuhashi score (RTS) is no longer accurate to predict the survival of patients with lung cancer metastases to the spine. This study is to identify additional prognostic factors in those patients, develop a modified prognostic score based on RTS, and verify the accuracy of the score in prediction.

METHODS

Our study included patients with lung cancer metastases to the spine who underwent surgery for spine metastasis. Potential prognostic factors were analyzed. Points were allocated for prognostic factors obtained from survival analyses. A modified score was developed by including prognostic factors and their points to RTS. Accuracy of the modified score was evaluated by comparing the coincidence between predicted and observed survival. Kaplan-Meier analysis and Cox regression models were used. Predictive values of scores for 6-month survival were measured via receiver operating characteristic (ROC) curves.

RESULTS

Targeted therapy and tumor markers were additional independent prognostic factors. In the modified score, 2 and 1 points were allocated to the new evaluation factors. The points for factors based on RTS remained the same, and two prognostic groups were redefined. For group A patients who were predicted to live for less than 6 months, conservative procedures would be recommended. For group B patients who were predicted to live for 6 months or more, palliative surgery would be recommended. When comparing the modified score to RTS, the area under the receiver operating characteristic curve (AUCROC) and accuracy of score were improved.

CONCLUSIONS

The modified RTS has improved prognostic accuracy in patients with lung cancer metastases to the spine.

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.

Surgical Technique of Vertebral Body Removal and Anterior Reconstruction in L5 Spondylectomy

Introduction

L5 spondylectomy for the treatment of spinal tumor is a technically demanding surgery because of the complex anatomy of major vessels, the obscurity of the posterior exposure from the iliac wings, and the increased comparative size of the L5 vertebral body. In this study, we present a surgical technique of L5 spondylectomy, vertebral body removal, and anterior reconstruction for a case with solitary spinal metastatic renal cell carcinoma (RCC).

Technical Note

A 54-year-old man underwent right total nephrectomy for RCC one year ago. At the one-year postoperative follow-up, CT scan and MRI revealed a solitary L5 spinal metastasis. A two-stage posteroanterior approach was performed. To facilitate vertebral body removal, transverse processes were separated from the vertebral body by using the posterior approach. On the basis of the anterior approach, the vertebral body was removed via the interval space between the left common iliac vessels. Reconstruction was performed by using a liquid-nitrogen-frozen, tumor-bearing bone mixed with an autogenous bone graft in an expandable titanium cage.

Results

No intraoperative complications were observed. Postoperatively, the patient exhibited muscle weakness in the tibialis anterior and extensor hallucis longus bilaterally but improved with time. Seven months after the operation, the patient was able to walk independently. At the recent 2.5-year follow-up, the local recurrence of lesions was nonexistent. The bone graft had fused with the adjacent vertebrae.

Conclusion

This report described a novel technique for L5 spondylectomy that can facilitate safe L5 vertebral body removal and demonstrated the effectiveness of liquid-nitrogen-frozen, tumor-bearing bone mixed with autogenous bone graft in anterior reconstruction both in terms of oncologic safety and biological healing.

Motor and Sensory Impairments of the Lower Extremities After L2 Nerve Root Transection During Total en Bloc Spondylectomy

STUDY DESIGN

Retrospective study.

OBJECTIVE

The purpose of this study was to examine motor and sensory impairments of the lower extremities after L2 nerve root transection during total en bloc spondylectomy (TES) for spinal tumors.

SUMMARY OF BACKGROUND DATA

At our institute, for TES at L3 to L5 lumbar levels, the nerve roots are preserved. However, at the level of L1 and L2, the vertebral resection and spinal reconstruction via a posterior approach is employed with transection of the nerve roots during dissection and resection of the vertebra.

METHODS

This study included 13 patients who had undergone TES for spinal tumors involving L2 between 2007 and 2016. Postoperative motor function of the lower extremities was quantified using the Manual Muscle Testing grade for the iliopsoas (IP) and quadriceps femoris (QF) muscles, and a grade of the modified Frankel Classification. Postoperative sensory impairment was quantified by the sites of lower extremity pain and numbness.

RESULTS

An initial decrease in strength of the IP and QF muscles in more than 60% of the patients, with a decline in the modified Frankel grade in 76.9%, was observed at 1-week after surgery. All patients recovered by the final follow-up, with 12 of the 13 patients walking without a gait aid. The other patient, who had undergone a bilateral dissection of L3 nerve root during TES of L2 and L3, had a mild QF muscle weakness, requiring a cane for walking. Eleven of 13 patients developed pain or numbness in the groin or thigh area after surgery, with the most common area being the anterior aspect of the thigh.

CONCLUSION

Although IP and QF weakness was observed in the majority of patients who underwent bilateral transection of L2 nerve roots during TES, these deficits recovered over time and did not finally affect activities of daily living.

LEVEL OF EVIDENCE

4.

Total En Bloc Spondylectomy for the Fifth Lumbar Solitary Metastasis by a Posterior-Only Approach

BACKGROUND

Relatively few cases of total en bloc spondylectomy (TES) for the L5 tumors have been reported. TES in the lower lumbar region is usually performed through a combined anterior and posterior approach. TES for L5 tumors by a posterior-only approach is technically challenging.

CASE DESCRIPTION

A 62-year-old woman with persistent pain in her lumbosacral area and lower extremities and numbness of her lateral left lower extremity for 2 months came to our department. She had undergone radical mastectomy 4 years earlier. X-ray and magnetic resonance imaging (MRI) showed that the tumor had destroyed the vertebral body of L5. No other lesions were revealed by emission computed tomography (ECT) or positron emission tomography/computed tomography (PET/CT). With a diagnosis of breast cancer and a solitary metastasis to L5, the patient was treated with posterior-only TES of the L5 tumor and reconstruction. The whole procedure took 10 hours, and her intraoperative blood loss was 9000 mL. The lumbar and leg pain of the patient disappeared postoperatively without serious complications. She started walking 4 weeks after surgery and resumed her daily life. New multiple metastases developed 6 months after surgery, with no sign of local recurrence. Despite active treatment, she died 18 months after surgery.

CONCLUSION

TES of the L5 tumor can be achieved by a posterior-only approach, with good results and limited complications.

A Child with a Rare Extraosseous Extension and Pathologic Fracture from a Vertebral Hemangioma: A Case Report

CASE

We present a case of a pathologic vertebral fracture and encroachment into the spinal canal from a vertebral hemangioma in a 13-year-old boy. The original approach of embolization followed by an anterior-posterior resection and stabilization through a costotransversectomy had to be converted intraoperatively to a combined anterior and posterior approach secondary to excessive bleeding.

CONCLUSION

Because of the hypervascularity and the extensive nature of aggressive vertebral hemangiomas, surgeons attempting procedures similar to the case described herein must be prepared to adapt to the circumstances when preoperative embolization is not totally effective. Surgical technique, proper anesthesia, and patient clotting capacity are important factors to consider.

Indication for anterior spinal cord decompression via a posterolateral approach for the treatment of ossification of the posterior longitudinal ligament in the thoracic spine: a prospective cohort study

PURPOSE

For ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine, anterior decompression is the most effective method for relieving spinal cord compression. The purpose of this study was to prospectively analyze the surgical outcomes based on our strategy in the treatment of thoracic OPLL.

METHODS

This study included 23 patients who underwent surgery for thoracic OPLL based on the following strategy between 2011 and 2017. For patients with a beak-type OPLL in the kyphotic curve with a ≥ 50% canal occupying ratio, circumferential decompression via a posterolateral approach and fusion (CDF) was indicated. For other types of OPLL, posterior decompression and fusion (PDF) was commonly indicated. Posterior fusion without decompression (PF) was applied when the spinal cord was separated from the posterior spinal elements. Clinical and radiological outcomes were compared among the CDF, PDF, and PF groups with a minimum of 20-month follow-up.

RESULTS

Ten, eleven, and two patients underwent CDF, PDF, and PF, respectively. The preoperative Japanese Orthopedic Association (JOA) score in the CDF group was significantly lower than that in the PDF group. The average recovery rate, according to JOA score, was 63%, 56%, and 25% in the CDF, PDF, and PF groups, respectively. The result in the CDF group was better than that in the PF group.

CONCLUSIONS

Anterior decompression was appropriate for patients with localized spinal cord compression by a large OPLL in the kyphotic curve, and CDF via a posterolateral approach appears to be safe and effective. These slides can be retrieved under Electronic Supplementary Material.

A Novel Technique for Total En bloc Spondylectomy of the Fifth Lumbar Tumor Through Posterior-Only Approach

STUDY DESIGN

A retrospective study.

OBJECTIVE

To describe a new surgical technique for total en bloc spondylectomy (TES) of the fifth lumbar (L5) tumor and evaluate the efficacy and safety of this new technique.

SUMMARY OF BACKGROUND DATA

TES has been considered an optimal treatment for tumor, including certain spinal tumors, but it requires a combined posterior-anterior approach, which is often complicated by a long operation time, considerable blood loss and severe trauma.

METHODS

Seven patients with primary or solitary metastatic tumors of L5 were treated with this new technique in our center between March 2014 and November 2017. The critical points were fabrication of the iliac graft, dissection, resection, and reconstruction. Other parameters including surgical time, blood loss, complications, pre- and postoperative neurological function, tumor control, and overall survival (OS) were presented and analyzed.

RESULTS

All the included patients received one stage TES. The mean surgical time was 365.7 minutes with an average blood loss of 2514.3 mL. No serious perioperative complication was observed or reported during the mean follow-up period of 27.4 months. Wound disruption occurred in one patient and numbness of the left lower limb in another, but both recovered rapidly after appropriate management. Adventitial avulsion of the abdominal aorta occurred during dissection in one patient. Two patients died during the follow-up period due to advanced malignancy. One patient was alive but developed a newly diagnosed thoracolumbar tumor in 40 months. The other four patients recovered well without evidence of disease. All patients were able to walk independently 3 to 4 weeks after operation, with satisfied fusion of the iliac grafts in a mean period of 6.7 months after operation. No evidence of internal fixation failure occurred.

CONCLUSION

This new technique offers satisfactory surgical exposure, total en bloc spondylectomy, reliable reconstruction, and good tumor control for certain L5 tumors through the posterior-only approach.

LEVEL OF EVIDENCE

4.

FOUR-LEVEL EN BLOC VERTEBRECTOMY: A NOVEL TECHNIQUE AND LITERATURE REVIEW

Objective:

To demonstrate a novel technique for multilevel en bloc post-vertebrectomy reconstruction.

Methods:

A novel technique for en bloc multiple post-vertebrectomy reconstruction was used in a patient presenting for curative resection of Ewing's Sarcoma at the oncology center of a public university hospital.

Results:

The procedure described was feasible for en bloc resection of the four vertebrae. The reconstruction was acceptable and satisfactory in terms of mechanical stability and was without any neurological sequelae in the patient.

Conclusion:

The use of an allograft with a locked intramedullary nail was an adequate solution for reconstructing the anterior and medial spines after multilevel vertebrectomy. In addition, the association of four intramedullary nails provided stability to the reconstruction. Immediate benefits of the technique compared to other commonly used techniques were shorter hospitalization times and reduced surgical morbidity. Level of Evidence V, Clinical study of a new surgical technique and a literature review.

Development and Validation of a Novel Survival Prediction Model in Patients With Spinal Metastasis From Non-small Cell Lung Cancer

STUDY DESIGN

Retrospective study.

OBJECTIVE

The aim of this study was to develop a model for predicting survival of patients with non-small cell lung cancer (NSCLC) spinal metastasis and compare its accuracy with the existing scoring systems.

SUMMARY OF BACKGROUND DATA

Spinal metastasis is commonly seen in advanced NSCLC and usually associated with poor survival prognosis.

METHODS

A total of 376 patients with NSCLC spinal metastases admitted to our institution from January 2010 to October 2016 were enrolled. They were randomly assigned at a 3:1 ratio to a training cohort (n = 282) and a validation cohort (n = 94). A nomogram for survival prediction was established by identifying and integrating significant prognostic factors, and then subjected to bootstrap validation in both training and validation cohorts. The discrimination was measured by concordance index (C-index). Predictive accuracy was compared with three existing models by the receiver-operating characteristic curve (ROC) and area under ROC in both training and validation cohorts.

RESULTS

Six independent prognostic factors including sex (P = 0.008), the presence of visceral metastasis (P = 0.008), the number of metastases in the vertebral body (P = 0.011), Frankel score (P < 0.001), D-dimer (P = 0.002), and sensitive epidermal growth factor receptor mutation (p < 0.001) were identified and entered into the nomogram. The calibration curves for probability of 3-, 6-, 12- and, 24-month overall survival showed good agreement between the predictive risk and the actual risk. The C-index of the nomogram was 0.708 (95% confidence interval [CI], 0.674-0.742) in the training cohort and 0.683 (95% CI, 0.619-0.747) in the validation cohort. Model comparison showed that this nomogram had better predictive accuracy than the Tomita et al, Tokuhashi et al, and Schwab et al scoring systems (P < 0.05 in the training cohort).

CONCLUSION

We established and validated a novel nomogram that could be used to predict the survival outcome of patients with NSCLC spinal metastasis, thus helping clinicians in decision making and individualized care planning of such patients.

LEVEL OF EVIDENCE

4.

Delayed-Onset Paraplegia Due to Spinal Cord Infarction After Repeated Tumor Excision Surgeries of the Thoracic Spine

Tumor excision surgeries of the spine present a distinct challenge regarding the maintenance of spinal cord blood supply because they often require preoperative embolization of segmental arteries, ligation of the corresponding nerve roots, and circumferential exposure of the dural sac. The authors present a case of delayed-onset spinal cord infarction after repeated tumor excision surgeries of the thoracic spine. A 49-year-old man had undergone a left nephrectomy for renal cell carcinoma, 2 pulmonary metastasectomies, and excision of a left sixth rib metastasis before referral to the authors' institution. He had a recurrence of the bone metastasis involving the left fourth and fifth ribs and T5 vertebra. He underwent 3 tumor excision surgeries, including spondylectomy of T5 and T7, for the repeated tumor recurrences involving the thoracic spine. These surgeries required preoperative embolization of 9 segmental arteries at 6 consecutive levels and ligation of 6 nerve roots at 3 consecutive levels. Thirty hours after the third surgery, the neurologic deficit worsened. The postoperative paraplegia was diagnosed as delayed-onset spinal cord infarction via magnetic resonance imaging. This is the first case report describing delayed-onset paraplegia due to spinal cord ischemia caused by embolization of segmental arteries and ligation of nerve roots in multi-spinal levels for spine tumor surgeries. In spine tumor surgery, embolization of bilateral segmental arteries at 4 or more consecutive levels and/or ligation of bilateral nerve roots pose a risk for ischemic spinal cord disease. [Orthopedics. 2019; 42(1):e131-e134.].