Multilevel en bloc spondylectomy for tumors of the thoracic and lumbar spine is challenging but rewarding

Single-Component Dual-Functional Autoboost Strategy by Dual Photodynamic and Cyclooxygenase-2 Inhibition for Lung Cancer and Spinal Metastasis

Coloading adjuvant drugs or biomacromolecules with photosensitizers into nanoparticles to enhance the efficiency of photodynamic therapy (PDT) is a common strategy. However, it is difficult to load positively charged photosensitizers and negatively charged adjuvants into the same nanomaterial and further regulate drug release simultaneously. Herein, a single-component dual-functional prodrug strategy is reported for tumor treatment specifically activated by tumor microenvironment (TME)-generated HOCl. A representative prodrug (DHU-CBA2) is constructed using indomethacin grafted with methylene blue (MB). DHU-CBA2 exhibited high sensitivity toward HOCl and achieved simultaneous release of dual drugs in vitro and in vivo. DHU-CBA2 shows effective antitumor activity against lung cancer and spinal metastases via PDT and cyclooxygenase-2 (COX-2) inhibition. Mechanistically, PDT induces immunogenic cell death but stimulates the gene encoding COX-2. Downstream prostaglandins E2 and Indoleamine 2,3 dioxygenase 1 (IDO1) mediate immune escape in the TME, which is rescued by the simultaneous release of indomethacin. DHU-CBA2 promotes infiltration and function of CD8+ T cells, thus inducing a robust antitumor immune response. This work provides an autoboost strategy for a single-component dual-functional prodrug activated by TME-specific HOCl, thereby achieving favorable tumor treatment via the synergistic therapy of PDT and a COX-2 inhibitor.

Total en bloc vertebrectomy and immunochemotherapy for chondrosarcoma colliding with intraosseous lymphoma

A 59-year-old woman diagnosed with a Grade I chondrosarcoma in T7 underwent total en bloc vertebrectomy. Analysis of the surgical piece established diagnosis of a Grade 1 chondrosarcoma confined to T7. Surprisingly, an infiltration with diffuse large B-cell lymphoma was found. Systemic disease was ruled out and diagnosis was established as intracompartmental Grade 1 chondrosarcoma colliding with intraosseous extranodal diffuse large B-cell lymphoma. Resection of chondrosarcoma was considered complete and treatment with four cycles of RCHOP was indicated. Two years after surgery, the patient remains at complete metabolic response. To date, this is the first reported case of chondrosarcoma colliding with lymphoma. Although Grade 1 chondrosarcoma is typically managed with local control through complete surgical resection, the mentioned finding of the lymphoma indicated the need for systemic treatment with immunochemotherapy.

Implant failure and revision strategies after total spondylectomy for spinal tumors

Background

Although there have been several risk factors reported for implant failure (IF), little consensus exists. Potential applicable measures to protect patients from IF are relatively few. This study aimed to discover new risk factors for IF and explore potential protective measures from IF after total spondylectomy for spinal tumors.

Methods

A total of 145 patients undergoing total spondylectomy for thoracic and lumbar spinal tumors between 2010 and 2021 were included from three tertiary university hospitals. Patient demographic and surgical characteristics and follow-up outcomes were collected.

Results

During a mean follow-up of 53.77 months (range, 12 to 149 months), 22 of 145 patients (15.17%) developed IF. Patients undergoing thoracolumbar junctional region (T12/L1) resection were more likely to develop IF compared to those undergoing surgery at other vertebral levels (HR = 21.622, 95% CI = 3.567-131.084, P = 0.001). Patients undergoing titanium mesh cage reconstruction were more likely to develop IF compared to patients undergoing expandable titanium cage reconstruction (HR = 8.315, 95% CI = 1.482-46.645, P = 0.016). Patients with bone cement augmentation around the cage were less likely to develop IF compared to those not receiving bone cement augmentation (HR = 0.015, 95% CI = 0.002-0.107, P < 0.001). Of the 22 patients with IF, 14 (63.63%) accepted personalized revision surgery.

Conclusion

The use of an expandable cage and the use of bone cement augmentation around the anterior column support cage are protective measures against IF after total spondylectomy.

A Systematic Review of Perioperative Complications in en Bloc Resection for Spinal Tumors

STUDY DESIGN

Systematic review.

OBJECTIVE

En bloc resection is a major, invasive surgical procedure designed to completely resect a vertebral tumor with a sufficient margin. It is technically demanding and potentially poses risks of perioperative complications. In this systematic review, we investigated the incidence of complications after en bloc resection for spinal tumors.

METHODS

We screened PubMed and Embase databases for relevant English publications, from 1980 to 2020, using the following terms: spine OR spinal AND en bloc AND tumor. Using a standard PRISMA template, after the initial screening, full-text articles of interest were evaluated.

RESULTS

Thirty-six studies with 961 patients were included. The overall mean age of patients was 49.6 years, and the mean follow-up time was 33.5 months. There were 560 complications, and an overall complication rate of 58.3% (560/961). The 5 most frequent complications were neurological damage (12.7%), hardware failure (12.1%), dural tear and cerebrospinal fluid leakage (10.6%), wound-related complications (7.6%) and vascular injury and bleeding (7.3%). The complication-related revision rate was 10.7% (103/961). The average incidence of complication-related death was 1.2% (12/961).

CONCLUSIONS

En bloc resection is a surgical procedure that is very invasive and technically challenging, and the possible risks of perioperative complications should not be neglected. The overall complication rate is high. However, complication-related death was rare. The advantages of surgery should be weighed against the serious perioperative morbidity associated with this technique.

Spinal tumours: recommendations of the Polish Society of Spine Surgery, the Polish Society of Oncology, the Polish Society of Neurosurgeons, the Polish Society of Oncologic Surgery, the Polish Society of Oncologic Radiotherapy, and the Polish Society of Orthopaedics and Traumatology

PURPOSE

The purpose of these recommendations is to spread the available evidence for evaluating and managing spinal tumours among clinicians who encounter such entities.

METHODS

The recommendations were developed by members of the Development Recommendations Group representing seven stakeholder scientific societies and organizations of specialists involved in various forms of care for patients with spinal tumours in Poland. The recommendations are based on data yielded from systematic reviews of the literature identified through electronic database searches. The strength of the recommendations was graded according to the North American Spine Society's grades of recommendation for summaries or reviews of studies.

RESULTS

The recommendation group developed 89 level A-C recommendations and a supplementary list of institutions able to manage primary malignant spinal tumours, namely, spinal sarcomas, at the expert level. This list, further called an appendix, helps clinicians who encounter spinal tumours refer patients with suspected spinal sarcoma or chordoma for pathological diagnosis, surgery and radiosurgery. The list constitutes a basis of the network of expertise for the management of primary malignant spinal tumours and should be understood as a communication network of specialists involved in the care of primary spinal malignancies.

CONCLUSION

The developed recommendations together with the national network of expertise should optimize the management of patients with spinal tumours, especially rare malignancies, and optimize their referral and allocation within the Polish national health service system.

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.

Surgical and Oncological Outcomes of En-Bloc Resection for Malignancies Invading the Thoracic Spine

OBJECTIVE(S)

There is still limited data in the literature concerning the survival of patients with tumors of the thoracic spine. In this study, we analyzed clinical features, perioperative and long-term outcomes in patients who underwent vertebrectomy for cancer. Furthermore, we evaluated the survival and surgical complications.

METHODS

We retrospectively reviewed all cases of thoracic spinal tumors treated by the same team between 1998 and 2018. We divided them into three groups according to type of tumor (primary vertebral, primary lung and metastases) and compared outcomes. For each patient, Overall Survival (OS) and Cumulative Incidence of Relapse (CIR) were estimated. Complications and survival were analyzed using a logistic model.

RESULTS

Seventy-two patients underwent thoracic spine surgery (40 in group 1, 16 in each group 2 and 3). Thirty patients died at the end of the observation at a mean follow up time of 60 months (41%). The 5-year overall survival was 72% (95% CI: 0.52-0.84), 20% (95% CI: 0.05-0.43) and 27% (95% CI: 0.05-0.56) for each group, respectively. CIR of group 3 was higher (HR 2.57, 95% CI: 1.22-5.45, p = 0.013). The logistic model revealed that age was related to complications (p = 0.04), while surgery for a type 3 tumor was related to mortality (p = 0.02).

CONCLUSIONS

Although the cohort size was limited, primary vertebral tumors displayed the best 5-y-OS with an acceptable complications rate. The indication of surgery should be advised by a multidisciplinary team and only for selected cases. Finally, the use of a combined approach does not increase the risk of complications.

3D-printed vertebral body for anterior spinal reconstruction in patients with thoracolumbar spinal tumors

OBJECTIVE

A 3D-printed vertebral prosthesis can be used to reconstruct a bone defect more precisely because of its tailored shape, with its innermost porous structure inducing bone ingrowth. The aim of this study was to evaluate the clinical outcomes of using a 3D-printed artificial vertebral body for spinal reconstruction after en bloc resection of thoracolumbar tumors.

METHODS

This was a retrospective analysis of 23 consecutive patients who underwent surgical treatment for thoracolumbar tumors at our hospital. En bloc resection was performed in all cases, based on the Weinstein-Boriani-Biagini surgical staging system, and anterior reconstruction was performed using a 3D-printed artificial vertebral body. Prosthesis subsidence, fusion status, and instrumentation-related complications were evaluated. Stability of the anterior reconstruction method was evaluated by CT, and CT Hounsfield unit (HU) values were measured to evaluate fusion status.

RESULTS

The median follow-up was 37 (range 24-58) months. A customized 3D-printed artificial vertebral body was used in 10 patients, with an off-the-shelf 3D-printed artificial vertebral body used in the other 13 patients. The artificial vertebral body was implanted anteriorly in 5 patients and posteriorly in 18 patients. The overall fusion rate was 87.0%. The average prosthesis subsidence at the final follow-up was 1.60 ± 1.79 mm. Instrument failure occurred in 2 patients, both of whom had substantial subsidence (8.47 and 3.69 mm, respectively). At 3 months, 6 months, and 1 year postoperatively, the mean CT HU values within the artificial vertebral body were 1930 ± 294, 1997 ± 336, and 1994 ± 257, respectively, with each of these values being significantly higher than the immediate postoperative value of 1744 ± 321 (p < 0.05).

CONCLUSIONS

The use of a 3D-printed artificial vertebral body for anterior reconstruction after en bloc resection of the thoracolumbar spinal tumor may be a feasible and reliable option. The low incidence of prosthesis subsidence of 3D-printed endoprostheses can provide good stability instantly. Measurement of HU values with CT is a valuable method to evaluate the osseointegration at the bone-metal interface of a 3D-printed vertebral prosthesis.

Intralesional Marginal Resection for Osteoblastoma in the Mobile Spine: Experience From a Single Center

Osteoblastoma (OB) is a benign bone tumor with aggressive behavior and a tendency for local recurrence. The appropriate surgical strategy for spinal OB remains unclear. This retrospective study aimed to verify the clinical efficacy and safety of intralesional marginal resection of OB in the mobile spine. We enrolled 50 consecutive patients with spinal OB between January 2009 and December 2019. The tumors were staged based on the Enneking system, with 21 and 29 lesions being determined as stage 2 (St.2) and stage 3 (St.3), respectively. Among them, 42 patients underwent intralesional marginal resection, five underwent extensive curettage, and three underwent en bloc resection successfully since their lesions were limited to the posterior element in a single vertebra. We analyzed clinical characteristics, perioperative and follow-up images, surgical details, and follow-up data. Within a median follow-up duration of 50 (range: 24–160) months, six (12.0%) patients had local recurrence. The recurrence rates among patients who underwent intralesional marginal resection, curettage, en bloc resection were 7.1%(3/42), 60.0%(3/5), and 0%(0/3), respectively. The recurrence rate of intralesional marginal resection of St.3 lesions was slightly higher than that of St.2 lesions (7.7%[2/26] vs. 6.3%[1/16]). There were 16(38.1%), 3(60.0%), and 0 patients with surgical complications among those who underwent intralesional marginal resection, curettage, and en bloc resection, respectively. Local recurrence was observed in five (5/14, 35.7%) patients who had vertebral artery extension and in none who did not have vertebral artery extension (p = 0.02). Our findings suggest that intralesional marginal resection could be an appropriate treatment choice for patients with spinal OB, both St.2 and St.3 lesions, with an acceptable local recurrence rate and a low risk of complications. Vertebral artery extension could be a strong risk factor for local recurrence in patients with spinal OB.

Mechanical Failure After Total En Bloc Spondylectomy and Salvage Surgery

Objective

Total en bloc spondylectomy (TES) is a curative surgical method for spinal tumors. After resecting the 3 spinal columns, reconstruction is of paramount importance. We present cases of mechanical failure and suggest strategies for salvage surgery.

Methods

The medical records of 19 patients who underwent TES (9 for primary tumors and 10 for metastatic tumors) were retrospectively reviewed. Previously reported surgical techniques were used, and the surgical extent was 1 level in 16 patients and 2 levels in 3 patients. A titanium-based mesh-type interbody spacer filled with autologous and cadaveric bone was used for anterior support, and a pedicle screw/rod system was used for posterior support. Radiotherapy was performed in 11 patients (pre-TES, 5; post-TES, 6). They were followed up for 59 ± 38 months (range, 11–133 months).

Results

During follow-up, 8 of 9 primary tumor patients (89%) and 5 of 10 metastatic tumor patients (50%) survived (mean survival time, 124 ± 8 months vs. 51 ± 13 months; p=0.11). Mechanical failure occurred in 3 patients (33%) with primary tumors and 2 patients (20%) with metastatic tumors (p=0.63). The mechanical failure-free time was 94.4 ± 14 months (primary tumors, 95 ± 18 months; metastatic tumors, 68 ± 16 months; p=0.90). Revision surgery was performed in 4 of 5 patients, and bilateral broken rods were replaced with dual cobalt-chromium alloy rods. Repeated rod fractures occurred in 1 of 4 patients 2 years later, and the third operation (with multiple cobalt-chromium alloy rods) was successful for over 6 years.

Conclusion

Considering the difficulty of reoperation and patients’ suffering, preemptive use of a multiple-rod system may be advisable.

Factors associated with spinal fixation mechanical failure after tumor resection: a systematic review and meta-analysis

Background

No available meta-analysis has been published that systematically assessed spinal fixation mechanical failure after tumor resection based on largely pooled data. This systematic review and meta-analysis aimed to investigate the spinal fixation failure rate and potential risk factors for hardware failure.

Methods

Electronic articles published between January 1, 1979, and January 30, 2021, were searched and critically evaluated. The authors independently reviewed the abstracts and extracted data on the spinal fixation failure rate and potential risk factors.

Results

Thirty-eight studies were finally included in the meta-analysis. The pooled spinal fixation mechanical failure rate was 10%. The significant risk factors for hardware failure included tumor level and cage subsidence. Radiotherapy was a potential risk factor.

Conclusion

The spinal fixation mechanical failure rate was 10%. Spinal fixation failure is mainly associated with tumor level, cage subsidence and radiotherapy. Durable reconstruction is needed for patients with these risk factors.

Integrated Custom Composite Polyetheretherketone/Carbon fiber (PEEK/CF) Vertebral Body Replacement (VBR) in the Treatment of Bone Tumors of the Spine: A Preliminary Report From a Multicenter Study

STUDY DESIGN

Retrospective, multicenter chart, and radiologic review.

OBJECTIVE

To present the first case series of bone tumors of the spine surgically reconstructed with a new custom, fully radiolucent, polyetheretherketone/carbon fiber (PEEK/CF) vertebral body replacement (VBR) integrated system.

SUMMARY OF BACKGROUND DATA

Surgical resections of spinal tumors result in large defects and local recurrence remains a concern. Current titanium-based implants adversely affects postoperative imaging, directly affects ability to identify tumor recurrence, and for delivery of radiotherapy treatments. PEEK/CF spinal implants allows for improved tumor surveillance, precise pre-radiation Computed Tomography planning, and reduces interference with post-reconstructive adjuvant radiotherapy.

METHOD

Thirteen patients with spinal tumors underwent vertebral body resection and reconstruction with an integrated, fully radiolucent, custom PEEK/CF vertebral body replacement, and radiolucent posterior PEEK/CF screw-rod system and/or radiolucent anterior PEEK/CF plate system. Clinical and radiographic data were tabulated. Need for adjuvant radiotherapy determined based on final tissue histology and extent of surgical margins. Postoperative surveillance imaging were reviewed for local tumor recurrence.

RESULTS

The ability to integrate the PEEK/CF VBR connected to either the posterior screw-rod system, or anterior plate system provided immediate stability. The VBR was placed directly on cancellous vertebral body surface in 46.2% of cases. Loosening of the distal, or proximal, aspect of posterior system was seen in 15.4% of cases. There was no clinical or radiographic evidence of VBR migration and subsidence at latest follow up. Local recurrence occurred in one (7.7%) patient.

CONCLUSION

This is the first series to describe the use of a fully-radiolucent, integrated, PEEK/CF implant system for spinal tumor reconstruction. The use of a PEEK/CF VBR system integrated to either the anterior plate, or posterior screw-rod system is feasible and allows for superior postoperative surveillance imaging and effective delivery of postoperative adjuvant radiotherapy.Level of Evidence: 4.

Application of Controlled Hypotension During Surgery for Spinal Metastasis

With advances in tumor treatment, metastasis to bone is increasing, and surgery has become the only choice for most terminal patients. However, spinal surgery has a high risk and is prone to heavy bleeding. Controlled hypotension during surgery has outstanding advantages in reducing intraoperative bleeding and ensuring a clear field of vision, thus avoiding damage to important nerves and vessels. Antihypertensive drugs should be carefully selected after considering the patient's age, different diseases, etc, and a single or combined regimen can be used. Hypotension also inevitably leads to a decrease in perfusion of important organs, so the threshold of hypotension and the maintenance time of hypotension should be strictly limited, and the monitoring of important organs during the operation is particularly important. Information such as blood perfusion, blood oxygen saturation, cardiac output, and neurophysiological conduction potential changes should be obtained in a timely fashion, which will help to reduce the risk of hypotension. In short, when applying controlled hypotension, it is necessary to choose an appropriate threshold and duration, and appropriate monitoring should be conducted during the operation to ensure the safety of the patient.

Video-Assisted Thoracoscopic En Bloc Vertebrectomy for Spine Tumors: Technique and Outcomes in a Series of 33 Patients

BACKGROUND

In en bloc vertebrectomy, the posterior approach is associated with limited access to anterior structures (vertebral body, esophagus, aorta, azygos vein). Video-assisted thoracoscopic surgery (VATS) might prove to be advantageous during thoracic en bloc vertebrectomy by allowing a combined anterior-posterior access in the prone position. We describe the technique and review the outcomes of 33 cases of video-assisted thoracoscopic en bloc vertebrectomy.

METHODS

A retrospective, single-center cohort study included all cases of VATS with a minimum follow-up of 1 year. A team of thoracic and orthopaedic surgeons performed the surgical procedure with the patient in a single, prone position. Anterior release was carried out thoracoscopically, followed by posterior en bloc tumor removal.

RESULTS

From 2003 to 2019, 33 patients were included. Nine patients underwent total vertebrectomy (8 had single-level and 1 had 3-level), and 24 patients underwent partial vertebrectomy (1 had single-level, 8 had 2-level, 13 had 3-level, and 2 had 4-level). Ten patients had pulmonary resection. Histology revealed 18 cases (55%) of primary bone tumors, 6 cases (18%) of lung cancer invading the spine, 6 cases (18%) of solitary metastasis, and 3 other cases (9%). The margins were tumor-free in 28 cases (85%). The median operative time was 240 minutes (range, 150 to 510 minutes), with a median blood loss of 1,200 mL (range, 400 to 6,700 mL), and there were 2 cases of conversion to thoracotomy. A total of 33 complications occurred in 18 patients (55%), and these were predominantly pulmonary. One death was surgery-related (infection). One patient had a persistent monoplegia. At a median follow-up of 63 months (range, 12 to 156 months), there were 21 surviving patients (64%) with 2 local recurrences and 1 distant recurrence, and 2 patients (6%) were lost to follow-up. The survival rates were 94% at 1 year, 71% at 2 years, and 68% at 5 years.

CONCLUSIONS

VATS en bloc vertebrectomy may be indicated for T2-to-T11 spine tumors with the exception of massive tumors, substantial chest wall and/or mediastinal invasion, and lung cancer exceeding 7 cm. The technique yielded satisfactory surgical and oncologic outcomes.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

En bloc resection and reconstruction of a huge chondrosarcoma involving multilevel upper thoracic spine and chest wall: case report

Background

En bloc resection of malignant tumors involving upper thoracic spine is technically difficult. We surgically treated a patient with grade 2 chondrosarcoma involving T1–5, left upper thoracic cavity, and chest wall.

Case presentation

A 37 years old, male patient was referred to our hospital for a huge lump involved left shoulder and chest wall. In order to achieve satisfied surgical margins, anterior approach, posterior approach, and lateral approach were carried out sequentially. After en bloc tumor resection, the upper thoracic spine was reconstructed with a 3D-printed modular vertebral prosthesis, and the huge chest wall defect was repaired by a methyl methacrylate layer between 2 pieces of polypropylene mesh. Postoperatively, the patient suffered from pneumonia and neurological deterioration which fully recovered eventfully. At 24 months after operation, the vertebral prosthesis and internal fixation were intact; there was no tumor local recurrence, and the patient was alive with stable pulmonary metastases.

Conclusion

This case report describes resection of a huge chondrosarcoma involving not only multilevel upper thoracic spine, but also entire left upper thoracic cavity and chest wall. Although with complications, en bloc tumor resection with combined surgical approach and effective reconstructions could improve oncologic and functional prognosis in carefully selected spinal tumor 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.

Vertebral-specific activation of the CX3CL1/ICAM-1 signaling network mediates non-small-cell lung cancer spinal metastasis by engaging tumor cell-vertebral bone marrow endothelial cell interactions

Rationale: The spine is one of the most common metastatic sites of non-small cell lung cancer (NSCLC), and NSCLC spinal metastasis results in serious consequences. Metastatic extravasation of disseminated cancer cells including increased invasiveness, adhesion and transendothelial migration is crucial for tumor metastasis. This study aimed to investigate the mechanisms underlying NSCLC spinal metastasis based on the C-X3-C motif chemokine ligand 1- (CX3CL1) and intercellular adhesion molecule-1- (ICAM-1) mediated signaling network. Methods: Immunohistochemistry, western blotting, and reverse transcription-quantitative PCR were conducted to detect the distribution of CX3CL1/ICAM-1 in different organs. Transwell, adhesion, and transendothelial migration assays were performed to evaluate the regulatory effects of CX3CL1/ICAM-1 on NSCLC cell invasion, adhesion, and transendothelial migration in vitro. A spontaneous spinal metastasis mouse model was established via injection of NSCLC cells into the left cardiac ventricle of NOD/SCID mice. The effects of CX3CL1/ICAM-1 on NSCLC spinal metastasis in vivo were validated using bioluminescent, micro-computerized tomography, immunohistochemistry and histological analyses. Results: CX3CL1 expression was specifically higher in vertebral bone compared with limb bones and lung tissue, and was associated with NSCLC spinal metastasis. Mechanically, vertebral bone marrow endothelial cells (VBMECs) enhanced NSCLC cell invasion via CX3CL1 signaling-mediated activation of the PI3K/AKT pathway. Furthermore, we found that VBMECs effectively induced ICAM-1-dependent NSCLC cell adhesion in coordination with platelets through the CX3CL1/ICAM-1/LFA-1 pathway. Meanwhile, CX3CL1 enhanced NSCLC cell transendothelial migration by increasing permeability of VBMECs via ICAM-1-dependent activation of the Src/GEF-H1 pathway. Interestingly, NSCLC cells were indicated to promote CX3CL1 secretion of VBMECs through MAPK14/ADMA17-dependent CX3CL1 release and NF-κB-dependent CX3CL1 synthesis. Based on these findings, we revealed a novel feedback cycle between circulating NSCLC cells and VBMECs mediated by CX3CL1/ICAM-1 signaling. Further disengagement of the CX3CL1/ICAM-1-mediated feedback cycle in vivo significantly restricted metastasis and prolonged mouse survival. Conclusions: Our results indicated a unique feedback cycle between circulating NSCLC cells and VBMECs mediated by CX3CL1/ICAM-1 signaling, which is necessary for NSCLC spinal metastasis. This work provides a new perspective for underlying the mechanisms of NSCLC spinal metastasis and indicates potential novel targets for the prevention of NSCLC spinal metastasis.

A modern multidisciplinary approach to a large cervicothoracic chordoma using staged en bloc resection with intraoperative image-guided navigation and 3D-printed modeling: illustrative case

BACKGROUND

Cervicothoracic junction chordomas are uncommon primary spinal tumors optimally treated with en bloc resection. Although en bloc resection is the gold standard for treatment of mobile spinal chordoma, tumor location, size, and extent of involvement frequently complicate the achievement of negative margins. In particular, chordoma involving the thoracic region can require a challenging anterior access, and en bloc resection can lead to a highly destabilized spine.

OBSERVATIONS

Modern technological advances make en bloc resection more technically feasible than ever before. In this case, the successful en bloc resection of a particularly complex cervicothoracic junction chordoma was facilitated by a multidisciplinary surgical approach that maximized the use of intraoperative computed tomography–guided spinal navigation and patient-specific three-dimensional–printed modeling.

LESSONS

The authors review the surgical planning and specific techniques that facilitated the successful en bloc resection of this right-sided chordoma via image-guided parasagittal osteotomy across 2 stages. The integration of emerging visualization technologies into complex spinal column tumor management may help to provide optimal oncological care for patients with challenging primary tumors of the mobile spine.

The use of autologous free vascularized fibula grafts in reconstruction of the mobile spine following tumor resection: surgical technique and outcomes

OBJECTIVE

Reconstruction of the mobile spine following total en bloc spondylectomy (TES) of one or multiple vertebral bodies in patients with malignant spinal tumors is a challenging procedure with high failure rates. A common reason for reconstructive failure is nonunion, which becomes more problematic when using local radiation therapy. Radiotherapy is an integral part of the management of primary malignant osseous tumors in the spine. Vascularized grafts may help prevent nonunion in the radiotherapy setting. The authors have utilized free vascularized fibular grafts (FVFGs) for reconstruction of the spine following TES. The purpose of this article is to describe the surgical technique for vascularized reconstruction of defects after TES. Additionally, the outcomes of consecutive cases treated with this technique are reported.

METHODS

Thirty-nine patients were treated at the authors' tertiary care institution for malignant tumors in the mobile spine using FVFG following TES between 2010 and 2018. Postoperative union, reoperations, complications, neurological outcome, and survival were reported. The median follow-up duration was 50 months (range 14-109 months).

RESULTS

The cohort consisted of 26 males (67%), and the median age was 58 years. Chordoma was the most prevalent tumor (67%), and the lumbar spine was most affected (46%). Complete union was seen in 26 patients (76%), the overall complication rate was 54%, and implant failure was the most common complication, with 13 patients (33%) affected. In 18 patients (46%), one or more reoperations were needed, and the fixation was surgically revised 15 times (42% of reoperations) in 10 patients (26%). A reconstruction below the L1 vertebra had a higher proportion of implant failure (67%; 8 of 12 patients) compared with higher resections (21%; 5 of 24 patients) (p = 0.011). Graft length, number of resected vertebrae, and docking the FVFG on the endplate or cancellous bone was not associated with union or implant failure on univariate analysis.

CONCLUSIONS

The FVFG is an effective reconstruction technique, particularly in the cervicothoracic spine. However, high implant failure rates in the lumbar spine have been seen, which occurred even in cases in which the graft completely healed. Methods to increase the weight-bearing capacity of the graft in the lumbar spine should be considered in these reconstructions. Overall, the rates of failure and revision surgery for FVFG compare with previous reports on reconstruction after TES.

One-stage posterior en-bloc spondylectomy following reconstruction with individualized 3D printed artificial vertebrae for multi-segment thoracolumbar metastases: case report and literature review

In thoracolumbar vertebral tumors, reconstruction of complex multi-segment thoracolumbar vertebrae after total en-bloc spondylectomy (TES) is still challenging. In recent years, with the development of 3D printing technology, individualized 3D printed artificial vertebrae have been attempted to reconstruct complex multi-segment thoracolumbar spine. Compared with traditional titanium mesh or bone transplantation, it helps reduce long-term complications, bringing a new dawn for reconstructing multi-segment thoracolumbar spine. A 69-year-old female complained of low back pain with limited motion for 1 month. More than 2 months ago, she underwent radical mastectomy due to breast cancer (Luminal A subtype). Imageology examination revealed an osteolytic lesion involving the T11-L1 vertebra. She was performed one-stage 3-segment (T11-L1) en-bloc spondylectomy via posterior approach, and then an artificial vertebrae produced by a novel individualized 3D printing technology was used for reconstruction. The patient was follow-up for 2 years, and she recovered well, with no tumor recurrence, and no complications after spinal reconstruction. The application of individualized 3D printed artificial vertebrae in multi-segment thoracolumbar spine reconstruction can not only reconstruct the bone defect more accurately through the individualized design, but the porous design is able to achieve biomechanical performance comparable to that of cancellous bone, and it is conducive to inducing bone growth, all of which help reduce long-term mechanical complications. Furthermore, the application of artificial vertebrae in surgery can significantly shorten the operation time, reduce intraoperative blood loss and reduce the risk of perioperative complications. Therefore, individualized 3D printed artificial vertebrae is a good choice for complex multi-segment thoracolumbar spine reconstruction.

Customized "Whole-Cervical-Vertebral-Body" Reconstruction After Modified Subtotal Spondylectomy of C2-C7 Spinal Tumor Via Piezoelectric Surgery

BACKGROUND

Radical resection is the first-line option in managing cervical primary chondrosarcoma. Favorable anterior reconstruction is challenging after multilevel total spondylectomy in the cervical spine.

OBJECTIVE

To illustrate the application of piezoelectric surgery and three-dimensional (3D) printing techniques in spine surgery.

METHODS

A 27-yr-old patient was referred to our center with complaints of nocturnal neck pain and right upper extremity weakness. A 2-stage radical tumor resection was conducted using piezoelectric surgery with pathologically tumor-free margins. A 3D-printed titanium microporous prosthesis (3D-PTMP) was designed to reconstruct the anterior column of the cervical spine between C1 and T1 for stability.

RESULTS

The whole intraoperative blood loss was 2300 mL over the 2 procedures. The patient had an uneventful recovery, regaining ambulatory status 3 wk after the 2 operations without ventilator support or other severe complications. By the final 14-mo follow-up, the patient had achieved marked pain relief and favorable neurological improvement; a postoperative computed tomography scan indicated a good position of the 3D-printed construct between the endplates with no sign of tumor recurrence or implant subsidence.

CONCLUSION

The applications of piezosurgery in total spondylectomy and in 3D-PTMP in reconstruction can be a favorable alternative for managing multilevel cervical spinal tumors. Further studies are warranted to validate this surgical strategy.

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.

Multi-level En Bloc Resection as a Preferred Salvage Therapy for Recurrent Thoracolumbar Chondrosarcoma: A Comparative Study With Piecemeal Resection

STUDY DESIGN

A retrospective analysis was performed.

OBJECTIVE

The aim of this study was to evaluate the feasibility and effectiveness of multilevel en bloc resection versus piecemeal resection for recurrent thoracolumbar chondrosarcoma (CHS).

SUMMARY OF BACKGROUND DATA

Multilevel en bloc resection for recurrent thoracolumbar CHS is rarely performed.

METHODS

Included in this retrospective study were 27 patients with recurrent thoracolumbar CHS who received either multilevel en bloc resection or piecemeal resection as a salvage revision procedure in our center between 2010 and 2018. Relevant data between the two methods were compared. Relapse-free survival (RFS) and overall survival (OS) were analyzed by log-rank analysis.

RESULTS

Our series comprised 16 males and 11 females with a mean age of 40.7 years. Multilevel en bloc resection was performed in 17 patients, and piecemeal resection in 10 patients. Of the 17 patients receiving multilevel en bloc resection, five patients experienced recurrence, of whom three died, whereas in the 10 patients receiving piecemeal resection, seven experienced recurrence and all of them died, showing a significant difference between the two groups (P = 0.04 for recurrence, P = 0.007 for death). Complications occurred more frequently in the patients receiving multilevel en bloc resection (P = 0.04), but RFS and OS were prolonged significantly in this group of patients as compared with piecemeal resection group (56.8 ± 9.7 vs. 17.2 ± 4.2, P = 0.016; 67.3 ± 8.4 vs. 21.4 ± 3.5, P = 0.002).

CONCLUSION

Multilevel en bloc resection as a salvage therapy for recurrent thoracolumbar CHS is technically challenging with high risk of complications, but it can significantly prolong RFS and OS of such patients as compared with piecemeal resection.

LEVEL OF EVIDENCE

4.

Sagittal en bloc resection of primary tumors in the thoracic and lumbar spine: feasibility, safety and outcome

This study is to test feasibility, safety and the outcome of sagittal en bloc resection of paravertebral primary tumors in the thoracic and the lumbar spine. Sagittal en bloc resection was planned based on WBB classification and performed via combined anterior-posterior or anterior-posterior-lateral approach in 9 consecutive patients with aggressive benign or malignant paravertebral primary tumors in the thoracic and lumbar spine. Surgical margins were evaluated both radiologically and histopathologically. Follow-up data regarding survival rate, local control, morbidity, hardware failure and postoperative function were collected at around 2 years after surgery. En bloc resection was achieved in all patient with wide margin in 7/9 patients, marginal and intralesional margin in 2/9 patients. Survival rate and local control rate were 100%. There were 4/9 cases of major complications and 2/9 cases of minor complications with an overall morbidity rate of 67% (6/9). All but one patient with intraoperative spinal cord injury were free of neurological deficits and fully mobile in absence of any indication of hardware failure. With a careful choice of surgical procedure, sagittal en bloc resection of paravertebral primary tumor in the thoracic and lumbar spine is feasible, safe and effective.

Function Preservation or Oncological Appropriateness in Spinal Bone Tumors?: A Case Series of Segmental Resection of the Spinal Canal Content (Spinal Amputation)

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

To evaluate (1) if the segmental resection of the content of the spinal canal could provide an Enneking appropriate tumor-free margin for local control of primary bone tumors surrounding and invading the canal and (2) the safety profile of the segmental resection of the neurostructures.

SUMMARY OF BACKGROUND DATA

Treatment outcomes of primary malignant and benign aggressive bone tumors of the spine have been dramatically changed by the application of the musculoskeletal oncologic principles described by Enneking. However, the efficacy of spinal oncology surgery might be limited by unique features of spinal anatomy.

METHODS

Database search was conducted with the following inclusion criteria: en bloc resection, segmental inclusion of the spinal canal content in the surgical specimen, histologically proven diagnosis, minimum follow-up of 2 years. Exclusion criteria were piecemeal excision of the tumor (debulking) and diagnosis other than primary bone tumors (metastasis, or local extension of extraosseous tumors).

RESULTS

A consecutive cohort of eight patients (three men, five women) was available for review. Two patients died within 3 months from the surgery for systemic disease progression or sequelae of the surgery. En bloc resection with segmental spinal canal content inclusion was able to achieve local control of the disease in four out of remaining six cases (66.7%) at an average follow-up of 68.7 months (range 12-174 mo). Three patients in whom local control was achieved are free from disease at an average follow-up of 98.7 months (range 38-174), and one died for systemic disease progression (after 38 mo). Seven out of 8 patients (87.5%) experienced overall 16 complications.

CONCLUSION

En bloc resection including the spinal canal content (spinal amputation) to achieve a tumor-free margin might be considered to perform an Enneking appropriate treatment for motivated patients.

LEVEL OF EVIDENCE

4.

Surgical strategies for primary malignant tumors of the thoracic and lumbar spine

BACKGROUND

Primary malignant tumors of the thoracic and lumbar spine are rare. They are mainly hematologic malignancies and more rarely sarcomas or chordomas. Giant-cell tumors and osteoblastomas, while benign, are locally very aggressive and their excision should be discussed as an option. Other possibilities are tumors from nearby organs invading the spine, which are actually carcinomas, but may benefit from radical excision in select cases.

METHODS

Excision of these tumors is complex and must be integrated in the diagnostic and therapeutic strategy established by a specific multidisciplinary tumor board at a designated cancer center. Surgical resection must combine tumor excision with long-lasting reconstruction of the spine and neighboring soft tissues. The initial excision must be as complete as possible as the possibilities of repeat excision are nearly impossible if the first resection is not complete.

RESULTS

An exhaustive preoperative imaging workup is essential for determining the tumor's spread and for determining the best surgical strategy. This will often require participation of other surgical specialties, which are well versed in teamwork. Thanks to this multidisciplinary care, especially the participation of thoracic and plastic surgeons, significant progress has been made recently. The first is the possibility of doing very extensive tumor excisions at the spine and in the neighboring organs, thus expanding the surgical indications to patients who were previously considered as being inoperable. We will discuss the surgical strategy and surgical approaches by spine level. Bone and soft tissue reconstruction is more effective thanks to the introduction of new spinal instrumentation and coverage flaps, which have drastically reduced the intra- and postoperative complications. Lastly, the risk factors for neurological complications are better understood, making them easier to prevent and to treat, if they were to occur.

CONCLUSION

These advances have translated to better cancer outcomes, especially better control of the tumor with neoadjuvant therapies (targeted chemotherapy) and preoperative conformal radiotherapy.

Revision surgery for tumors of the thoracic and lumbar spine: causes, prevention, and treatment strategy

INTRODUCTION

Revision surgery in spine tumor surgery can offer peculiar challenges given the severity of the majority of these lesions and the complexity of surgical procedures that are required.

MATERIALS AND METHODS AND RESULTS

Based on literature review and on personal experience, surgical site infection, cerebrospinal fluid leakage, tumor recurrence and hardware failures are some of the possible causes of surgical revision in this set of patients.

CONCLUSIONS

The aim of this study is to evaluate the most frequent complications that can lead to revision in spine tumor patients, to provide suggestions on how to prevent these events and to offer reasonable strategies to properly plan and perform a revision surgery. These slides can be retrieved under Electronic Supplementary Material.

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.

Rod fracture and related factors after total en bloc spondylectomy

BACKGROUND CONTEXT

Several studies have reported favorable oncosurgical outcomes after total en bloc spondylectomy (TES) for treatment of primary malignant tumors or oligometastatic tumors. Considering that TES is indicated for patients with longer life expectancy, long-term instrumentation-related issues such as rod fracture needs to be addressed.

PURPOSE

To investigate delayed rod fracture and related factors after TES.

STUDY DESIGN

Multicenter, retrospective study.

PATIENT SAMPLE

Thirty-two patients who survived for more than 2 years after TES.

OUTCOME MEASURES

Rod fracture and related factors.

METHODS

The relationships between rod fracture and related factors were investigated using Kaplan-Meier survivorship analysis with log-rank test. The analyzed factors were sex, age (<60 or ≥60), tumor histology (primary or metastatic), location of resected tumor (thoracic [above T11], thoracolumbar [cases including T12-L1], or lumbar [below L2]), number of resected vertebrae (1, 2, or 3), anterior support method (expandable cage, mesh cage, or strut bone graft), rod diameter (5.5 mm or 6.0 mm), and history of radiotherapy including preoperative or postoperative radiotherapy.

RESULTS

The study population consisted of 18 men and 14 women, with a mean age of 49.0 years. Nineteen patients had primary tumors and 13 patients had metastatic tumors. The mean follow-up duration was 49.8 months (range, 24-166 months). Twelve of 32 patients (37.5%) experienced rod fractures at an average of 29.2 months (range, 8-93 months) after TES. Of these 12 patients, 8 underwent revision surgery caused by back pain aggravation (n = 7) or nonunion on computed tomography scan (n = 4). Location of resected tumor and history of radiotherapy were significantly associated with rod fracture (p = .004 and p = .019, respectively).

CONCLUSION

Rod fracture was not a rare complication after TES surgery. History of radiotherapy and TES at lumbar level were significant risk factors related to rod fracture. A robust strategy to obtain solid osseous fusion should be considered when planning TES.

Intraosseous Malignant Peripheral Nerve Sheath Tumor of 2 Consecutive Lumbar Vertebrae: A Case Report and Literature Review

BACKGROUND

Malignant peripheral nerve sheath tumor (MPNST), which refers to any malignant tumor that originates from peripheral nerve sheath cells, is rarely found in the spine. Primary intraosseous spinal MPNSTs are extremely uncommon; in fact, such an occurrence has been reported in a very limited number of cases hitherto. We report here one case of low-grade intraosseous MPNST in the lumbar vertebrae and review clinical research related to this rare tumor and modus operandi to its treatment.

CASE DESCRIPTION

A 51-year-old man suffering from lower back pain was initially diagnosed with lumbar tuberculosis. The intraoperative histopathologic examination, however, revealed that the occupying lesion was synovial sarcoma when surgeons intended to perform a debridement surgery of what was thought to be tuberculosis. The operation was therefore suspended. Two months later, the patient was referred to our institution. The pathologic sections were reexamined. Its results refuted the earlier thought of being synovial sarcoma, and a final diagnosis of MPNST was made. In addition, preoperative examination revealed that the tumor had advanced rapidly to the adjacent inferior vena cava and pedicle, which ruled out the possibility of performing a total en bloc spondylectomy. Therefore, a marginal resection for 2-level consecutive lumbar vertebrae was performed successfully via an anterior-posterior combined approach. No serious complications were detected at 18-month follow-up.

CONCLUSIONS

Preoperative biopsy is of great importance for the diagnosis of spinal tumors. Marginal resection of a complicated intraosseous spine MPNST via an anterior-posterior combined approach, despite being technically challenging, resulted in good survival and functional outcomes.

Quality of life, pain, and psychological factors in patients undergoing surgery for primary tumors of the spine

PURPOSE

Knowledge about quality of life (QOL), pain, and psychological factors in patients with primary tumors of the spine is limited, but is important in planning rehabilitation after surgery. Aims of this study were to assess the preoperative levels and improvement after surgery of these factors, and to identify the predictors of postoperative pain and QOL.

METHODS

Patients with primary tumors undergoing spine surgery were matched for sex and age with patients with metastatic tumors. QOL was measured at baseline and three months after surgery with the physical (PCS) and mental (MCS) components SF-12 subscales, pain intensity with a numeric rating scale (NRS), depression with the Beck Depression Inventory (BDI). Preoperative SF-12, NRS, and BDI levels and differences in follow-up improvement in SF-12 and NRS were compared across samples. LASSO regressions were performed to find predictors of follow-up SF-12 and NRS.

RESULTS

Patients with primary tumors showed better PCS and NRS, and similar BDI and MCS than patients with metastatic tumors. At follow-up, they showed stronger improvement in the MCS and no improvement in the PCS. All QOL scores were below those of the general population. Follow-up PCS was predicted by baseline PCS and BDI; MCS by baseline MCS; pain intensity by baseline pain intensity and BDI.

CONCLUSION

Patients with primary tumors of the spine suffer from moderate levels of physical and mental impairment. Depression influences surgical outcomes.

Three-Level Lumbar En Bloc Spondylectomy with Three-Dimensional-Printed Vertebrae Reconstruction for Recurrent Giant Cell Tumor

BACKGROUND

Primary malignancies involving the mobile spine often require total en bloc spondylectomy with complex mechanical reconstruction, which can be augmented with novel application of the 3-dimensional (3D)-printing technique.

CASE DESCRIPTION

A 51-year-old man presented with a 12-month history of progressive thigh pain and lower limb motor function loss, 36 months after T12-L4 instrumentation and fusion for giant cell tumor (GCT) of the L2 vertebrae before referral. The patient subsequently underwent successful curative management of recurrent GCT through denosumab treatment, L1-L3 total en bloc spondylectomy (TES), and a novel lumbopelvic reconstruction method with a 3D-printed lumbar vertebrae and screw-rod system.

CONCLUSIONS

To our knowledge, this is the first reported case of multilevel lumbar TES for GCT reconstructed using a 3D-printed vertebrae. Although TES-specifically in the lumbosacral spine-remains challenging due to its unique anatomy and increased risk of neurologic insult, it is an effective option for curative management of GCTs.

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.].

Three Level Thoracolumbar Spondylectomy for Recurrent Giant Cell Tumour of the Spine: A Case Report

Giant cell tumour (GCT) is a benign tumour but can be locally aggressive and with the potential to metastasise especially to the lungs. Successful treatments have been reported for long bone lesions; however, optimal surgical and medical treatment for spinal and sacral lesions are not well established. In treating spinal GCTs, the aim is to achieve complete tumour excision, restore spinal stability and decompress the neural tissues. The ideal surgical procedure is an en bloc spondylectomy or vertebrectomy, where all tumour cells are removed as recurrence is closely related to the extent of initial surgical excision. However, such a surgery has a high complication rate, such as dura tear and massive blood loss. We report a patient with a missed pathological fracture of T12 treated initially with a posterior subtraction osteotomy, who had recurrence three years after the index surgery and subsequently underwent a three level vertebrectomy and posterior spinal fusion.

A Novel Height-Adjustable Nano-Hydroxyapatite/Polyamide-66 Vertebral Body for Reconstruction of Thoracolumbar Structural Stability After Spinal Tumor Resection

BACKGROUND

Reconstruction of thoracolumbar structural stability is a formidable challenge for spine surgeons after vertebral body tumor resection. Various disadvantages of the currently used expandable or nonexpandable cages have limited their clinical applications. We sought to develop a novel prosthesis for clinical use and assess its preliminary clinical outcome in reconstruction of thoracolumbar structural stability after spinal tumor resection.

METHODS

Using data obtained from a retrospective analysis of the morphological characteristics of the thoracolumbar vertebrae and endplates in previously reported studies, we modified the nano-hydroxyapatite/polyamide-66 (n-HA/PA66) strut into a novel height-adjustable vertebral body. A retrospective study was performed of 7 patients who had undergone reconstruction of thoracolumbar structural stability with this novel prosthesis from August 2016 to January 2017.

RESULTS

A novel height-adjustable vertebral body (AHVB) composed of n-HA/PA66 with 2 separate components with a 163° contact surface at each end was manufactured. The height-adjustable range was 28-37 mm. No significant implant-related complications were observed in the process of operation. All patients experienced a significant reduction in pain, with the visual analog scale score decreasing from 7.9 to 4.0. Neurological improvement was assessed using the Frankel grading system after surgery. Postoperative radiographic and computed tomography/magnetic resonance imaging findings indicated that the operated segment was stable, the outcome of kyphosis correction was good, and no prosthesis subsidence or dislocation was observed.

CONCLUSION

This novel prosthesis has many advantages in the reconstruction of height, lordosis, and alignment after thoracolumbar spinal tumor resection and has a favorable prospect for clinical application.

Revision strategy and follow-up for implant failure in a case of combined anterior and posterior reconstruction after three-level en bloc vertebral body replacement and replacement of the aorta for chondrosarcoma of the thoracic spine

OBJECTIVE

In 2013, we reported a case of combined anterior and posterior reconstruction after three-level en bloc vertebral body replacement and replacement of the aorta for chondrosarcoma of the thoracic spine. Eight years after, we observed an implant failure and now report on revision strategy and 2-year follow-up (f/u) after revision.

METHODS

We report about the 2-year f/u of the same now 51-year-old gravedigger who needed to undergo revision surgery after implant failure. We did a combined anterior and posterior correction vertebral interbody fusion by (1) removal of broken screws in Th9 and L2, removal of broken titanium bars, correction of kyphosis, enhancement of the vertebral interbody fusion from Th8 to L4 using monoaxial titanium screws and cancellous bone transplantation and (2) removal of the broken plate and the loose cage, implantation of a novel expandable PEEK cage from Th11 to L1 and anterior stabilization from Th9/10 to L2/3, as well as autologous and allogeneic cancellous bone transplantation.

RESULTS

Two years after revision surgery, the patient presented fully reintegrated without any complains. No painkillers needed to be taken. Pain was reported with 2 out of 10 on the VAS.

CONCLUSION

Both procedures offer a good primary stabilization with excellent pain reduction and good return to life. Limited information on long-term survivors is known. Therefore, the theoretical advantage of a biological solution needs to be checked in the long-term f/u for consistency.

Single-stage multi-level construct design incorporating ribs and chest wall reconstruction after en bloc resection of spinal tumour

PURPOSE

Multi-level reconstruction incorporating the chest wall and ribs is technically demanding after multi-segmental total en bloc spondylectomy (TES) of thoracic spinal tumours. Few surgical techniques are reported for effective reconstruction. A novel and straightforward technical reconstruction through posterior-lateral approach was presented to solve the extensive chest wall defect and prevent occurrences of severe respiratory dysfunctions after performing TES. The preliminary outcomes of surgery were reviewed.

METHODS

Multi-level TES was performed for five patients with primary or recurrent thoracic spinal malignancies through posterior-lateral approach. The involved ribs and chest wall were removed to achieve tumour-free margin. Then titanium mesh with allograft bone and pedicle screw-rod system were adopted for the circumferential spinal reconstruction routinely. Titanium rods were modified accordingly to attach to the screw-rod system proximally, and the distal end of rods was dynamically inserted into the ribs.

RESULTS

The mean surgery time was 6.7 hours (range 5-8), with the average blood loss of 3260 ml (range 2300-4500). No severe neurological complications were reported while three patients had complaints of slight numbness of chest skin (no. 1, 3, and 5). No severe respiratory complications occurred during peri-operative period. No implant failure and no local recurrence or distant metastases were observed with an average follow-up of 12.5 months.

CONCLUSIONS

The single-stage reconstructions incorporating spine and chest wall are straightforward and easy to perform. The preliminary outcomes of co-reconstructions are promising and favourable. More studies and longer follow-up are required to validate this technique.

Surgical approach selection for total spondylectomy for the treatment of giant cell tumors in the lumbar spine: A retrospective analysis of 12 patients from a single center

AIM

To describe the selection of the surgical approach used for total spondylectomy in the treatment of giant cell tumors of the lumbar spine.

METHODS

This retrospective study included 12 patients with giant cell tumors of the lumbar spine who underwent total spondylectomy. The effect of the Weinstein-Boriani-Biagini surgical staging and tumor location on the approach selected was evaluated.

RESULTS

Two tumors were treated using the posterior approach: one located in L1, extending into layers A∼D and involving sectors 2∼6, and the other located in L4, extending into layers B∼D and involving sectors 4∼11. Four tumors (one each located in L1, L2, L3, and L4) were treated by a combined posterior and anterolateral approach as the tumors involved sectors 5∼6 or 7∼8. Six tumors were treated using a combined posterior and anterior approach, two tumors located in L4, extending into layers A∼D and involving sectors 1∼12, and associated with a soft tissue mass extending into layer A and involving sectors 5∼8; and four tumors located in L5. Complications were observed in 9 of the 12 patients.

CONCLUSIONS

A posterior approach is the obvious strategy for tumors located in L1∼L4 and extending into layers B∼D or A and involving sectors 1∼3 or 10∼12. For tumors invading beyond layer A and involving sectors 1∼12, including those with a soft tissue mass extending from layer A, with involvement of sectors 4∼9, a posterior approach combined with an anterolateral or anterior approach is required. For L5 tumors, a combined posterior and anterior approach is needed.

Modified En Bloc Spondylectomy for Tumors of the Thoracic and Lumbar Spine: Surgical Technique and Outcomes

BACKGROUND

Total en bloc spondylectomy (TES) for the treatment of spinal tumors decreases local recurrence and improves survival compared with intralesional resection. TES approaches vary in both the number of stages to complete the procedure and instruments with which osteotomies are performed.

METHODS

We describe a 2-stage technique that employs the use of threadwire saws. We performed a retrospective review of cases of primary tumors and solitary metastases involving the thoracic or lumbar spine treated with use of our modified technique at our institution between 2010 and 2016, identifying eligible patients by searching for specific phrases in operative reports found in our oncologic database. Clinical notes, operative notes, imaging reports, and pathology reports were reviewed for all patients.

RESULTS

Thirty-three patients underwent our modified technique, in which we pass a threadwire saw between the vertebral body and the thecal sac. The most common tumor type was chordoma (64%), and tumors were most commonly located in the lumbar spine (61%). There were no intraoperative injuries to the spinal cord or great vessels. One patient experienced a dural tear secondary to the passage of a saw. Seventeen (52%) of the patients had perioperative complications, with 1 death. Seven (22%) of the patients had complications occurring within 90 days after discharge, and 8 (25%) had complications occurring >90 days after discharge. Instrumentation failure was observed in 8 cases (25%). Negative margins were obtained in 94% of the cases. Local recurrence was observed in 2 cases (6%). The majority of patients had normal motor function at the time of the most recent follow-up.

CONCLUSIONS

Our modified en bloc spondylectomy represents an effective technique for the resection of spinal tumors in selected patients, allowing for visualization of vessels anterior to the spine and the avoidance of spinal cord injury.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Pleomorphic rhabdomyosarcoma infiltrating thoracic spine in a 59-year-old female patient: Case report

Rhabdomyosarcoma (RMS) represents a malignant tumor of skeletal muscle cells arising from rhabdomyoblasts. RMS represents the most common soft tissue sarcoma in children. In adults it is uncommon and accounts for less than 1% of all malignant solid tumors. While treatment protocols are well known for children, there is no standardized regimen in adults. This is one reason, why the outcome in adults is worse than in children. We present the case of a 59-year-old female patient with pleomorphic rhabdomyosarcoma (PRMS) infiltrating the thoracic spine. Multimodality treatment was performed including en-bloc resection, adjuvant multidrug chemotherapy and radiation beam therapy. The patient was tumor free and had no relapse within 6 month follow-up.

Evidence-Based Review and Survey of Expert Opinion of Reconstruction of Metastatic Spine Tumors

STUDY DESIGN

Systematic review and consensus expert opinion.

OBJECTIVE

To provide surgeons and other health care professionals with guidelines for surgical reconstruction of metastatic spine disease based on evidence and expert opinion.

SUMMARY OF BACKGROUND DATA

The surgical treatment of spinal metastases is controversial. Specifically two aspects of surgical reconstruction are addressed in this study: (i) choice of bone graft used during surgery for metastatic spine tumors and (ii) the design of reconstruction or construct to stabilize.

METHODS

A systematic review of the available medical literature from 1980 to 2015 was conducted, and combined with consensus expert opinion from a recent survey of spine surgeons who treat metastatic spine tumors.

RESULTS

There is very little evidence in the literature to provide guidance on the use of bone graft in metastatic tumor reconstruction. There is little evidence in the literature to support the preferential use of one graft type over the other. Approximately, 41% of respondents said they used bone graft or bone graft substitutes to accomplish fusion. There were 17 studies that described the use of a prefabricated prosthetic, 10 studies describing the use of polymethyl methacrylate (PMMA) bone cement, and only three studies describing the use of bone graft for anterior column reconstruction. The use of structural allograft was most popular among the experts for anterior reconstruction, followed by cage reconstruction, and PMMA bone cement.

CONCLUSION

Achieving bony union may be of importance for the maintenance of spinal stability in the long term after reconstruction. Whether bony union is required for patients with shorter life expectancies is debatable. The literature supports the use of anterior reconstruction with either a prefabricated prosthetic or PMMA bone cement. It also supports the use of an anterior construct reinforced with bilateral posterior instrumentation when performing a three-column reconstruction.

LEVEL OF EVIDENCE

N/A.

[Total en bloc spondylectomy for spinal tumours: Technical aspects and surgical details]

OBJECTIVE

To describe the specific surgical details and report the lessons learned with a series of patients suffering from spinal tumours that underwent total en bloc spondylectomy (TES).

METHODS

A retrospective case series review is presented, together with an analysis of the clinical and technical variables, as well as the outcomes.

RESULTS

A total of 10 patients underwent TES (2000-2016) for primary (osteosarcoma, chondrosarcoma, fibrosarcoma and chordoma) and secondary spinal tumours (lung, breast, thyroid, oesophagus, and meningioma metastases). According to the Tomita classification, 2 patients had intra-compartmental tumours, and the rest presented as extra-compartmental. All patients experienced an improvement in their pain level after surgery. Nine patients preserved ambulation post-operatively and one patient developed paraplegia. Six patients needed subsequent operations for wound debridement, tumour recurrence, or revision of the fixation. Other complications included pneumothorax, pleural effusion and venous thrombosis. Four patients remain alive (4 months to 15 years follow-up). The rest died due to primary tumour progression (6.5 months to 12 years). A detailed description of the surgical steps, tips, and pitfalls is provided. Modifications of the technique and adjuncts to resection are commented on. Observation of some considerations (selection of candidates, careful blunt vertebral dissection, strict blood loss control, careful handling of the spinal cord, and maintenance of the radical resection concept at all stages) is key for a successful operative performance.

CONCLUSION

TES is a paradigmatic operation, in which the concept of radical resection provides functional effectiveness and improves survival in selected patients suffering from spinal tumours. Our preliminary experience allows us to highlight some specific and relevant features, especially those favouring a simpler and safer operation.