The lateral extracavitary approach to the thoracolumbar spine: a case series and systematic review

Endoscopic Versus Traditional Thoracic Discectomy: A Multicenter Retrospective Case Series and Meta-Analysis

BACKGROUND AND OBJECTIVES

Surgical treatment for symptomatic thoracic disc herniations (TDH) involves invasive open surgical approaches with relatively high complication rates and prolonged hospital stays. Although advantages of full endoscopic spine surgery (FESS) are well-established in lumbar disc herniations, data are limited for the endoscopic treatment of TDH despite potential benefits regarding surgical invasiveness. The aim of this study was to provide a comprehensive evaluation of potential benefits of FESS for the treatment of TDH.

METHODS

PubMed, MEDLINE, EMBASE, and Scopus were systematically searched for the term "thoracic disc herniation" up to March 2023 and study quality appraised with a subsequent meta-analysis. Primary outcomes were perioperative complications, need for instrumentation, and reoperations. Simultaneously, we performed a multicenter retrospective evaluation of outcomes in patients undergoing full endoscopic thoracic discectomy.

RESULTS

We identified 3190 patients from 108 studies for the traditional thoracic discectomy meta-analysis. Pooled incidence rates of complications were 25% (95% CI 0.22-0.29) for perioperative complications and 7% (95% CI 0.05-0.09) for reoperation. In this cohort, 37% (95% CI 0.26-0.49) of patients underwent instrumentation. The pooled mean for estimated blood loss for traditional approaches was 570 mL (95% CI 477.3-664.1) and 7.0 days (95% CI 5.91-8.14) for length of stay. For FESS, 41 patients from multiple institutions were retrospectively reviewed, perioperative complications were reported in 4 patients (9.7%), 4 (9.7%) required revision surgery, and 6 (14.6%) required instrumentation. Median blood loss was 5 mL (IQR 5-10), and length of stay was 0.43 days (IQR 0-1.23).

CONCLUSION

The results suggest that full endoscopic thoracic discectomy is a safe and effective treatment option for patients with symptomatic TDH. When compared with open surgical approaches, FESS dramatically diminishes invasiveness, the rate of complications, and need for prolonged hospitalizations. Full endoscopic spine surgery has the capacity to alter the standard of care for TDH treatment toward an elective outpatient surgery.

Diagnosis and Management of Thoracic Myelopathy

Thoracic myelopathy can be a challenging condition to diagnose and treat. Successful outcomes depend on early recondition of the pathology and appropriate surgical referral in cases of progressive neurologic deterioration. The thoracic cord is tethered in kyphosis by the dentate ligaments and contains a tenuous blood supply. These conditions make the thoracic cord particularly susceptible to external compression and ischemic damage. Careful preoperative planning with specific attention to the location and source of thoracic stenosis is critical to successful decompression and complication avoidance. The purpose of this discussion is to outline the common sources of thoracic myelopathy and current recommendations regarding diagnosis and management. The review concludes with an overview of the most up-to-date literature regarding clinical outcomes.

Multidisciplinary Surgical Approach Using Augmented Reality Preplanning for Resection of Giant Thoracic Schwannoma With Robotic-Assisted Thoracoscopic Mobilization

BACKGROUND AND IMPORTANCE

In adults, primary spinal cord tumors account for 5% of all primary tumors of the central nervous system, with schwannomas making up about 74% of all nerve sheath tumors. Thoracic schwannomas can pose a threat to neurovasculature, presenting a significant challenge to safe and complete surgical resection. For patients presenting with complex pathologies including tumors, a dual surgeon approach may be used to optimize patient care and improve outcomes.

CLINICAL PRESENTATION

A 73-year-old female previously diagnosed with a nerve sheath tumor of the fourth thoracic vertebra presented with significant thoracic pain and a history of falls. Imaging showed that the tumor had doubled in size ranging from T3 to T5. Augmented reality volumetric rendering was used to clarify anatomic relationships of the mass for perioperative evaluation and decision-making. A dual surgeon approach was used for complete resection. First, a ventrolateral left video-assisted thoracoscopic surgery was performed with robotic assistance followed by a posterior tumor resection and thoracic restabilization. The patient did well postoperatively.

CONCLUSION

Although surgical treatment of large thoracic dumbbell tumors presents a myriad of risks, perioperative evaluation with augmented reality, new robotic surgical techniques, and a dual surgeon approach can be implemented to mitigate these risks.

Transdural Ventral Sling Technique for Calcified Thoracic Disk Herniations

BACKGROUND

Surgery for thoracic disc herniations remains an ongoing challenge, with numerous surgical approaches, all with their own inherent risks. Discectomy via a posterior laminectomy was historically the treatment of choice; however, it was deemed very high risk with elevated rates of neurologic injury. The posterior transdural approach is an alternative surgical option for soft and calcified thoracic disc herniations.

METHODS

A 56-year-old female with many years of numbness/tingling in her hands and difficulty with fine motor tasks presented with progressive weakness and loss of balance in her legs. Imaging revealed a prominent focal central calcified disc herniation at the T5-T6 level causing severe effacement and distortion of the spinal cord. A posterior transdural approach for direct visualization of a large calcified disc herniation was performed, removing the calcified disc without the need for extensive exposure or entry into the thoracic cavity. A ventral sling of the dura was created to allow rotation of the spinal cord while removing the disc.

RESULTS

Intraoperative ultrasound confirmed complete disc resection, restoring cerebral spinal fluid flow circumferentially without residual impingement or cerebrospinal fluid leaks. At six months postsurgery, the patient's gait imbalance had resolved, and she had full lower extremity strength (5/5). Radiographic evaluation indicated stable implants without subsidence, pullout, fracture, or alignment loss.

CONCLUSIONS

The transdural approach is less invasive in nature, minimizes surgical exposure, patient morbidity, and provides better intraoperative control of the spinal cord. This constitutes an effective alternative surgical approach to both soft and calcified central thoracic disc herniations.

Unilateral Minimally Invasive Across-Midline Vertebral Column Resection Partially Corrects Thoracolumbar Kyphosis - A Case Series

OBJECTIVE

The goal of this study was to describe the indirect and partial correction of spine kyphotic deformities (secondary to various pathologies) achieved by minimally invasive posterolateral extracavitary approach (MIS PLECA) for corpectomy.

METHODS

The authors retrospectively reviewed a consecutive case series of 12 patients undergoing MIS PLECA in a single institution. Perioperative data were collected and follow-up computed tomographies and radiographs were reviewed to assess for interbody arthrodesis.

RESULTS

The mean age was 60.7 ± 20.8 years (58.4% males). The etiologies of deformity included pathological fracture (41.6%), acute trauma (30%), and infection. An expandable cage was used in 66.7% of patients for anterior reconstruction. The mean total estimated blood loss was 764.1 ± 332.9 ml. The mean operative time was 413.3 ± 98.8 minutes. The average length of hospital stay was 5.8 ± 2.5 days. A consistent degree of focal correction of sagittal alignment was seen in all patients with a mean correction of sagittal angle of 7.4 ± 4.3° (P < 0.0001). The mean duration of rehabilitation was 8.5 ± 6.7 days. All patients remained neurologically stable at the last follow-up with a mean follow-up period of 20.1 ± 12.8 months. Successful fusion was achieved in 91.7% at the last follow-up.

CONCLUSIONS

MIS PLECA for corpectomy appears to be a feasible, safe, and effective MIS technique for select patients, particularly those who cannot tolerate the traditional open approach. Additionally, a focal sagittal deformity correction can be achieved using MIS corpectomy.

Comparison of Anterior Approach and Posterior Circumspinal Decompression in the Treatment of Giant Thoracic Discs

STUDY DESIGN

Retrospective cohort study.

OBJECTIVES

The treatment of giant thoracic disc herniation (gTDH)remains challenging for surgeons worldwide because of its large volume and calcified or ossified nature and the limitations of the prior small-sample-size, single-center studies reporting comparative effectiveness. We aim to compare the anterior decompression and spinal fusion (ASF) and posterior circumspinal decompression and spinal fusion (PCDF) for patients with myelopathy due to gTDH in the largest study to date by sample size.

METHODS

Preoperative and postoperative functional status, surgical details, and complication rates were compared between the 2 groups.

RESULTS

A total of 186 patients were included: 63 (33.9%) ASF and 123(66.1%) PCDF. The PCDF group had significantly shorter operation duration (163.06 ± 53.49 min vs. 180.78 ± 52.06 min, P = 0.032) and a significant decrease in intraoperative blood loss(716.83 mL vs. 947.94 mL, P = 0.045), and also a shorter hospital length of stay (LOS) and postoperative LOS (6 vs. 7, P = 0.011). The perioperative complication rate (13.8% vs. 28.6%, P = 0.015) and surgery-associated complication rate(13.0% vs. 27.0%, P = 0.018) were significantly higher in the ASF group. A higher rate of complete decompression was achieved in the PCDF group. There were no observed significant differences in changes in functional status between the 2 groups.

CONCLUSION

PCDF for central or paracentral gTDHs is a highly effective and reliable technique. It can be performed safely with a low complication rate. If either procedure can adequately excise a central or paracentral gTDH, a PCDF approach may be a better option.

Fifty-year history of the evolution of spinal metastatic disease management

Spine metastases are a significant source of morbidity in oncology. Treatment of these spine metastases largely remains palliative, but advances over the past 50 years have improved the effectiveness of interventions for preserving functional status and obtaining local control while minimizing morbidity. While the field began with conventional external beam radiation as the primary treatment modality, a series of paradigm shifts and technological advances in the 2000s led to a change in treatment patterns. These advances allowed for an increased role of surgical decompression of neural elements, a shift in the stereotactic capabilities of radiation oncologists, and an improved understanding of the radiobiology of metastatic disease. The result was improved local control while minimizing treatment morbidity. These advances fit within the larger framework of metastatic spine tumor management known as the Neurologic, Oncologic, Mechanical, and Systemic disease decision framework. This dynamic framework takes into account the neurological function of the patient, the radiobiology of their tumor, their degree of mechanical instability, and their systemic disease control and treatment options to help determine appropriate interventions based on the individual patient. Herein, we describe the 50-year evolution of metastatic spine tumor management and the impact of various advances on the field.

Technical nuances and approach-related morbidity of anterolateral and posterolateral lumbar corpectomy approaches-a systematic review of the literature

Purpose

Approaches for lumbar corpectomies can be roughly categorized into anterolateral (AL) and posterolateral (PL) approaches. It remains controversial to date whether one approach is superior to the other, and no comparative studies exist for the two approaches for lumbar corpectomies.

Methods

A systematic review of the literature was performed through a MEDLINE/PubMed search. Studies and case reports describing technique plus outcomes and possible complications were included. Thereafter, estimated blood loss (EBL), length of operation (LOO), utilized implants, neurological outcomes, complication rates, and reoperation rates were analyzed.

Results

A total of 64 articles reporting on 702 patients including 513 AL and 189 PL corpectomies were included in this paper. All patients in the PL group were instrumented via the same approach used for corpectomy, while in the AL group the majority (68.3%) of authors described the use of an additional approach for instrumentation. The EBL was higher in the AL group (1393 ± 1341 ml vs. 982 ± 567 ml). The LOO also was higher in the AL group (317 ± 178 min vs. 258 ± 93 min). The complication rate (20.5% vs. 29.1%, p = 0.048) and the revision rate (3.1% vs. 9.5%, p = 0.004) were higher in the PL group. Neurological improvement rates were 43.8% (AL) vs. 39.2% (PL), and deterioration was only noted in the AL group (6.0%), while 50.2% (AL) and 60.8% (PL) showed no change from initial presentation to the last follow-up.

Conclusion

While neurological outcomes of both approaches are comparable, the results of the present review demonstrated lower complication and revision rates in anterolateral corpectomies. Nevertheless, individual patient characteristics must be considered in decision-making.

Spinal navigation applied to the anterior approach for the resection of thoracic disc herniation: patient series

BACKGROUND

Thoracic disc herniation (TDH) represents a challenge for spine surgeons. The goal of this study is to report the surgical technique and clinical results concerning the application of navigation to anterior transthoracic approaches.

OBSERVATIONS

Between 2017 and 2019, 8 patients with TDH were operated in the lateral decubitus by means of mini-open thoracotomy. An adapted patient referent frame was secured to the iliac wing. The high-speed drill was also navigated. Intraoperative three-dimensional scans were used for level identification, optimized drilling trajectory, and assessment of complete resection. At 12 months follow up, all patients were ambulatory. Seven out of 8 patients (87%) experienced a postoperative neurological improvement. We observed 2 postoperative complications: 1 case of pleural effusion and 1 case of abdominal wall weakness.

LESSONS

In order to increase the safety of anterior transthoracic discectomy, the authors applied the concepts of spinal navigation to the thoracotomy setting. The advantages of this technique include decrease in wrong-level procedure, continuous matching of intraoperative and navigation anatomical findings, better exposure of the TDH, optimized vertebral body drilling, and minimized risk of neurological damage. In conclusion, the authors consider spinal navigation as an important resource for the surgical treatment of patients with TDH.

[Lateral retropleural and retrodiaphragmatic approach in patients with spine trauma and diseases: a systematic review and meta-analysis]

BACKGROUND

Retropleural and/or retrodiaphragmatic approach is one of the options for anterolateral access to the thoracic spine and thoracolumbar region. This technique has no disadvantages associated with thoracotomy or extensive tissue dissection following posterolateral approaches.

OBJECTIVE

Systematic analysis of foreign and national researches devoted to the possibility, safety and effectiveness of lateral retropleural approach to the thoracic spine and meta-analysis of the most common complications associated with this approach.

MATERIAL AND METHODS

Initial searching revealed 133 abstracts for further study. Inclusion criteria: 1) available full-text version of the manuscript in English or Russian; 2) age of patients over 18 years; 3) description of lateral retropleural or retrodiaphragmatic approach complicated or not complicated by access-associated complications. According to these criteria, we enrolled 10 manuscripts.

RESULTS

Meta-analysis showed high (10.6%) probability of pleural injury associated with surgical approach. Compared to endoscopic transthoracic interventions, the above-mentioned access is characterized by similar or slightly greater blood loss (401.2 ml vs. 100-775 ml) and slightly longer surgery time (200.5 vs. 97.5-186 min) that may be due to small number of interventions and relatively little experience of such operations. The number of patients with approach-related complications is comparable to that for endoscopic transthoracic access (5% vs. 3.7-13.3%). Compared to transthoracic minithoracotomy, this approach is characterized by similar blood loss (401.2 vs. 391 ml), longer surgery time (200.5 vs. 168 min) and similar or lower morbidity (5% vs. 5-13.5%).

CONCLUSION

Minimally invasive anterolateral retropleural and/or retrodiaphragmatic approach to the thoracic spine and thoracolumbar junction for corpectomy and discectomy ensures effective spinal canal decompression and less incidence of complications following open or thoracoscopic thoracic spine surgery. Dissection of parietal pleura should be of special attention because injury of this structure occurs in 10.6% of cases. Skin incision 7.1 cm and rib resection for at least 5 cm may be valuable to prevent plural damage.

Transforaminal Thoracic Interbody Fusion for Thoracic Disc Prolapse: Surgicoradiological Analysis of 18 Cases

STUDY DESIGN

Retrospective observational study.

OBJECTIVES

Thoracic disc prolapse (TDP) surgeries have reported complications ranging from paraplegia to approach related complications. This study is to present a series of TDP patients surgically treated with transforaminal thoracic interbody fusion (TTIF). Emphasis on surgical technique and strategies to avoid complications are analyzed.

METHODS

Eighteen patients with TDP were included. Imagings were analyzed for end-plate changes and calcification. Type of disc prolapse (central/para-central) and percentage of canal occupancy were noted. Objective outcome was quantified with Visual Analogue Scale (VAS), modified Nurick's grade, and ASIA (American Spinal Injury Association) score. All complications were noted.

RESULTS

Eighteen patients (average age 43.65 years) having total 22 levels operated, that included double level (n = 2) and missed level (n = 2) are reported. All patients had myelopathy. Calcification of disc (n = 13), central disc prolapses (n = 9), para-central (n = 11) and more than 50% canal occupancy (n = 8) were noted. VAS back pain, modified Nurick's grade and ASIA grade improved significantly in all patients. One patient had postoperative transient deficit. The functional score achieved its maximum at 1 year follow-up and remained static at final follow-up of 65.05 months. Union was achieved in all patients.

CONCLUSIONS

The most important factor for outcome in TDP is the technical aspect of avoiding cord manhandling and avoiding wrong level surgeries. TTIF is not devoid of complications but can give good results to posterior approach trained surgeons.

Transpedicular Vertebrectomy With Circumferential Spinal Cord Decompression and Reconstruction for Thoracic Spine Metastasis: A Consecutive Case Series

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To study the feasibility, outcomes, and complications of transpedicular vertebrectomy (TPV), and reconstruction for metastatic lesions to the thoracic spine.

SUMMARY OF BACKGROUND DATA

Metastatic lesions to the thoracic spine may need surgical treatment requiring anterior-posterior decompression/stabilization. Anterior reconstruction may be performed using poly methyl meth acrylate (PMMA) cement or cages. Use of cement has been reported to be associated with complications.

METHODS

From 2008 to 2016, consecutive cases (single surgeon) undergoing TPV for thoracic spine metastasis (T2-12) were included. Demographic, surgical, and clinical data were collected through chart review. MRI, CT, positron emission tomography images were used to identify extent of disease, epidural spinal cord compression (ESCC), and degree of vertebral body collapse. Hall-Wellner confidence band was used for the survival curve.

RESULTS

Ninety six patients were studies with a median age 60 years. Most patients 56 (58%) presented with mechanical pain. 29% cases had lung metastasis. Single level TPV was performed in 73 patients (76%). Anterior reconstruction included PMMA in 78 patients (81.25%), and titanium cage in 18 patients (18.25%). Frankel grade improvement was seen in 16 cases (P = 0.013). ESCC improved by a median of 5.9 mm (P < 0.001). Kyphosis reduced by median of 7.5° (P < 0.001). VAS improved by median of seven (P < 0.001). Total 59 deaths were observed. The median survival time was estimated to be 6 months (95% CI: 5, 10). Surgical outcome and complication rates are similar between the two construct types. Correction of kyphosis was seen to be slightly better with the use of PMMA. Overall 29.16% cases developed complications (11.4% major). Two cases developed neurological deficit following epidural hematoma requiring surgery. One case had instrumentation failure from cement migration, needing revision.

CONCLUSION

The result of our study shows significantly improved clinical and radiological outcomes for TPV for thoracic metastatic lesions. We also discuss some important steps for use of PMMA to avoid complications.

LEVEL OF EVIDENCE

4.

A New High-Speed Shielded Curved Device Allowing Safe Posterior Thoracic Discectomy Through a Modified Transforaminal Thoracic Interbody Fusion Approach: Technique Description and Case Series

Background

The appropriate approach for surgical removal of thoracic disc herniations is controversial. The posterior approach historically acquired a bad reputation due to high rates of neurologic deterioration subsequent to spinal cord manipulation. The anterior approach has consequently gained popularity but entails a larger magnitude of surgery if open and is technically demanding if approached thoracoscopically. Approaching the thoracic disc posteriorly following unilateral facetectomy and pediculectomy was suggested in 1978. This study presents a technique for posterior unilateral thoracic discectomy through a hemilaminectomy, unilateral facetectomy, and hemipediculectomy, facilitated by a novel curved dorsally shielded high-speed device. Introducing the device ventral to the dural sac allows removal of calcified and soft disc fragments without relying on forceful manual maneuvers and avoiding manipulation of the spinal cord.

Methods

The maximal disc protrusion side is approached through a hemilaminectomy, unilateral facetectomy, and hemipediculectomy removing the superior half of the pedicle and exposing the disc transforaminally, allowing its removal using the device. Pedicle fixation and fusion concluded all procedures (TTIF). Between June 2014 and November 2018, 12 patients (6 men and 6 women) ages 23 to 74 years underwent posterior thoracic discectomy applying the above approach. The affected levels were D3 to D4 (1), D5 to D6 (1), D7 to D8 (1), D9 to D10 (1), D10 to D11 (3), D11 to D12 (4), and D12 to L1 (1).

Results

All patients presented with neurologic deterioration and all but 2 with pyramidal signs. All procedures were uneventful, without dural tears. None of the patients deteriorated neurologically. Average back pain visual analog scale scores decreased by 1.2, from 6.6 to 5.4. Average leg pain visual analog scale scores decreased by 2.2, from 6.6 to 4.4. Improvement was noted in Oswestry Disability Index scores and 6 SF-36 metrics.

Conclusions

The new curved device and approach allow for a faster, safer thoracic disc herniation removal.

Clinical Relevance

The proposed technique allows a safer treatment for thoracic disc herniations, reducing complication rates and improving patient outcome.

Posterior Percutaneous Endoscopic Technique Through Bilateral Translaminar Osseous Channels for Thoracic Spinal Stenosis Caused by Ossification of the Ligamentum Flavum Combined with Disk Herniation at the T10-11 Level: A Technical Note

BACKGROUND

The occurrence rate of thoracic spinal stenosis caused by ossification of the ligamentum flavum combined with disk herniation is lower than that of ossified ligamentum flavum in the thoracic spine, and the treatment method has rarely been reported. In this paper, we applied an endoscopic technique to a patient with thoracic spinal stenosis caused by ossification of the ligamentum flavum combined with disk herniation at the T10-11 level.

METHODS

We performed surgical decompression of the thoracic spinal cord for a patient diagnosed with thoracic spinal stenosis at the T10-11 level caused by ossification of the ligamentum flavum combined with disk herniation using percutaneous endoscopic surgery via the bilateral translaminar osseous channel approach. Pre- and postoperative computed tomography (CT) scan and magnetic resonance imaging (MRI) examinations were performed, and pre- and postoperative neurologic status was evaluated using the Modified Japanese Orthopaedic Association and visual analog scale scores.

RESULTS

The ossified ligamentum flavum and herniated disk material were removed through this osseous channel. Postoperative CT and MRI scanning revealed adequate decompression of the spinal cord at the T10-11 level. The patient was discharged home on postoperative day 3. At 6-month postoperative follow-up, the patient experienced complete resolution of T12 dermatomal numbness. The strength in her bilateral lower extremities improved slightly to grade 5.

CONCLUSIONS

We have applied percutaneous endoscopic surgery via bilateral translaminar osseous channels for the treatment of thoracic spinal stenosis caused by ossification of the ligamentum flavum combined with disk herniation. This surgery could provide sufficient decompression for thoracic spinal cord with minimum trauma.

Surgical treatment of thoracic disc herniation: an overview

BACKGROUND

Surgical treatment of thoracic disc herniation (TDH) is technically demanding due to its proximity to the spinal cord.

METHODS

Literature review.

RESULTS

Symptomatic TDH is a rare condition predominantly localized between T8 and L1. Surgical indications include intractable back or radicular pain, neurological deficits, and myelopathy signs. Giant calcified TDH (> 40% spinal canal occupation) are frequently associated with myelopathy, intradural extension, and post-operative complications. Careful pre-operative planning helps reduce the risk of complications. Pre-operative CT and MRI identify the hernia's location and size, calcifications, and intradural extension. The approach must provide adequate dural sac visualization with minimal manipulation of the cord. Non-anterior approaches are favoured if they provide at least equal exposure than anterior approach owing to higher risk of pulmonary morbidity associated with anterior approach. A transthoracic approach is recommended for central calcified herniated discs. A posterolateral approach is often suitable for non-calcified lateralized TDH. Thoracoscopic approaches are less invasive but have a substantial learning curve. Retropleural mini-thoracotomy is an acceptable alternative. Pre-operative identification of the pathological level is confirmed by intra-operative level check. Intra-operative cord monitoring is preferable but warrant further studies. Magnification and adequate lightening of the surgical field are paramount (microscope, thoracoscopy). Intra-operative CT scan with navigation is becoming increasingly popular since it provides real-time control on the decompression. Indications of fusion consist of pre-operative back pain, Scheuermann's disease, multilevel resection, wide vertebral body resection (> 50%), and herniation at thoracolumbar junction. Neurological deterioration, dural tear, and subarachnoid-pleural fistula are the most severe complications.

CONCLUSION

Further improvements are still warranted in thoracic spine surgery despite the advent of minimally invasive techniques. Intra-operative CT scan will probably enhance the safety of the TDH surgery.

Thoracic disc herniation: Surgical treatment

Thoracic disc herniation is rare and mainly occurs between T8 and L1. The herniation is calcified in 40% of cases and is labeled as giant when it occupies more than 40% of the spinal canal. A surgical procedure is indicated when the patient has severe back pain, stubborn intercostal neuralgia or neurological deficits. Selection of the surgical approach is essential. Mid-line calcified hernias are approached from a transthoracic incision, while lateralized soft hernias can be approached from a posterolateral incision. The complication rate for transthoracic approaches is higher than that of posterolateral approaches; however, the former are performed in more complex herniation cases. The thoracoscopic approach is less invasive but has a lengthy learning curve. Retropleural mini-thoracotomy is a potential compromise solution. Fusion is recommended in cases of multilevel herniation, herniation in the context of Scheuermann's disease, when more than 50% bone is resected from the vertebral body, in patients with preoperative back pain or herniation at the thoracolumbar junction. Along with complications specific to the surgical approach, the surgical risks are neurological worsening, dural breach and subarachnoid-pleural fistulas. Giant calcified herniated discs are the largest contributor to myelopathy, intradural extension and postoperative complications. Some of the technical means that can be used to prevent complications are explored, along with how to address these complications.

Anterior Versus Posterior Thoracic Discectomy: A Systematic Review

STUDY DESIGN

Systematic literature review.

OBJECTIVE

The aim of this study was to systematically review the current evidence in the literature on thoracic discectomies, to compare the clinical outcomes, and to determine whether there is evidence to support the use of either the anterior or posterior approach.

SUMMARY OF BACKGROUND DATA

Thoracic disc herniations (TDHs) often present with myelopathy, radiculopathy, or a combination of both. The posterior approach for thoracic discectomy has been associated with a lower complication rate, but no systematic review exists comparing the clinical outcomes.

METHODS

MEDLINE, EMBASE, and The Cochrane Library databases were searched in accordance with the PRISMA guidelines for studies performing an anterior or posterior thoracic discectomy. The methodological quality was assessed using the Methodological Index for Non-Randomized Studies checklist. The reported clinical outcomes were evaluated using risk ratio, with a P < 0.05 being considered statistically significant.

RESULTS

Thirty-seven clinical studies with 1156 patients with 1300 TDHs were included in this review. There was no statistically significant difference in the total neurological improvement or neurological worsening using either an anterior approach or a posterior approach (P = 0.02812 and P = 0.5232, respectively). However, there was a statistically significant higher rate of total complications in the anterior approach (P = 0.0024).

CONCLUSION

The anterior approach and posterior approach have been shown to be very similar in terms of neurological outcomes. Although the posterior approach was shown to have a lower rate of total complications, this was largely because of a decrease in minor respiratory complications seen in the anterior approach. The optimal approach may therefore be based on surgeon preference as well as patient factors, specifically cardiorespiratory with American Society of Anaesthesiologists grading.

LEVEL OF EVIDENCE

4.

Interbody distraction and vertebral body reconstruction with polymethylmethacrylate for the treatment of pathological fractures

OBJECTIVE Treatment of epidural spinal cord compression (ESCC) caused by tumor includes surgical decompression and stabilization followed by postoperative radiation. In the case of severe axial loading impairment, anterior column reconstruction is indicated. The authors describe the use of interbody distraction to restore vertebral body height and correct kyphotic angulation prior to reconstruction with polymethylmethacrylate (PMMA), and report the long-term durability of such reconstruction. METHODS A single institution, prospective series of patients with ESCC undergoing single-stage decompression, anterior column reconstruction, and posterior instrumentation from 2013 to 2016 was retrospectively analyzed. Several demographic, perioperative, and radiographic measurements were collected. Descriptive statistics were compiled, in addition to postoperative changes in anterior height, posterior height, and kyphosis. Paired Student t-tests were performed for each variable. Overall survival was calculated using the techniques described by Kaplan and Meier. RESULTS Twenty-one patients underwent single-stage posterior decompression with interbody distraction and anterior column reconstruction using PMMA. The median age and Karnofsky Performance Scale score were 61 years and 70, respectively. Primary tumors included renal cell (n = 8), lung (n = 4), multiple myeloma (n = 2), prostate (n = 2), and other (n = 5). Eighteen patients underwent a single-level vertebral body reconstruction and 3 underwent multilevel transpedicular corpectomies. The median survival duration was 13.3 months. In the immediate postoperative setting, statistically significant improvement was noted in anterior body height (p = 0.0017, 95% confidence interval [CI] -4.15 to -1.11) and posterior body height (p = 0.0116, 95% CI -3.14 to -0.45) in all patients, and improved kyphosis was observed in those with oblique endplates (p = 0.0002, 95% CI 11.16-20.27). In the median follow-up duration of 13.9 months, the authors observed 3 cases of asymptomatic PMMA subsidence. One patient required reoperation in the form of extension of fusion. CONCLUSIONS In situ interbody distraction allows safe and durable reconstruction with PMMA, restores vertebral height, and corrects kyphotic deformities associated with severe pathological fractures caused by tumor. This is accomplished with minimal manipulation of the thecal sac and avoiding an extensive 360° surgical approach in patients who cannot tolerate extensive surgery.

Thoracic corpectomy for neoplastic vertebral bodies using a navigated lateral extracavitary approach-a single-center consecutive case series: technique and analysis

Thoracic myelopathy is often caused by vertebral body fractures resulting from neoplastic conditions, traumatic events, or infectious diseases. One of the preferred procedures for treating it is the lateral extracavitary approach (LECA) with single-level or multilevel decompressive corpectomy and reconstruction. The aim of this retrospective study was to analyze the thoracic lateral extracavitary approach with corpectomy using vertebral body replacement systems (VBR-S) and dorsal reconstruction. Twenty-four patients with metastatic or primary lesions of thoracic vertebrae T2-T12 underwent spinal decompression and ventral column reconstruction with correction of spinal deformity via a LECA. One-level to four-level corpectomies were performed with additional navigated dorsal pedicle screw fixation at an average of two levels above and below the corpectomy lesion. None of the patients received preoperative spinal embolization, and the majority of the patients were admitted to radiotherapy postoperatively. Their mean age was 56 years (± 15), with a female-to-male sex ratio of 8 to 16. Patients with a minimum follow-up period of 16 months were included. The Karnofsky index, preoperative and postoperative numeric rating scale (NRS), and Frankel scale were measured. In addition, intraoperative loss of blood (LOB), units of packed red blood cell (PRBC) transfusions, the duration of the operation, and the hospitalization period were evaluated and correlated with preoperative and postoperative values. The majority of the patients were suffering from metastatic lesions and were treated with a 1 level corpectomy (median 1 level, range 1 to 4). The mean duration of surgery was 288 min (± 121) and the mean LOB was 1626 mL (± 1486 mL), with approximately two PRBC units per patient used. All patients were transferred to the intensive care unit (ICU) postoperatively, with a mean ICU stay of 2.0 days (± 1 day). The mean hospitalization period was 13 days (± 7 days). No implant-related failures or procedure-related deaths were observed. Significant differences were noted between the preoperative and postoperative Karnofsky index (74 vs. 84%) and NRS (4 vs. 2). One patient required revision surgery due to a superficial wound infection, and another needed revision surgery due to a dural tear. In another patient, an iatrogenic dural tear was repaired during the same surgical procedure and did not lead to postoperative complications. Four pleural effusions and one pneumothorax were observed, so that the overall complication rate was approximately 33%. Four of the patients died within 2 years of the operation due to progression of the primary disease. Lateral corpectomy and sagittal reconstruction of the thoracic spine using VBR-S conducted via a navigated LECA approach yields favorable results, despite the burden of neoplastic disease. These challenging procedures are accompanied by increased LOB and hospitalization periods, with moderate transfusion requirements. Surgery-related complications are low and local tumor control is satisfactory, despite the progression of the underlying neoplastic disease. However, optimal surgical therapy does not ensure long-term survival.Study design Retrospective analysis of thoracic corpectomiesLevel of evidence 4.

Novel Bilateral Extracavitary Approach for Thoracolumbar Decompression

BACKGROUND

Bilateral extracavitary approach (BECA) is an option for decompression cases that require a more extended ventral approach. The clear advantage is increased accessibility to the most ventral aspects of the spine from a bilateral perspective.

OBJECTIVE

To assess the safety and efficacy of thoracic and thoracolumbar decompression and/or reconstruction from BECA.

METHODS

A retrospective chart review was performed reviewing all patients who underwent BECA for thoracolumbar decompression from 2003 to 2012 at our institution. We recorded patient baseline characteristics, physical exam, surgical indications, perioperative interventions, and outcomes.

RESULTS

We performed 82 lateral extracavitary approaches and 10 BECAs. BECA indications included neoplasm, infection, and kyphotic deformity. Average patient age was 58 yr; 80% of BECA patients were male. Estimated blood loss was typically 1 to 3 L. Average length of stay postoperative was 12 d. Two patients required revisions; one for infection and one for revision of misplaced hardware. Eight patients improved at least one grade on the American Spinal Injury Association Impairment Scale (ASIA) or was originally ASIA E. Two patients declined 1 to 2 ASIA grades. Average length of follow-up was 16.8 mo.

CONCLUSION

BECA is an efficient technique with acceptable complication rates and similar risks to unilateral approaches. It should be considered when extensive bilateral decompression and/or reconstruction of the anterior thoracic or thoracolumbar spine is required.

[Rationale and complications of the anterior-lateral extrapleural retroperitoneal approach for unstable thoracolumbar fractures: Experience in 86 consecutive patients]

OBJECTIVES

To describe the rationale, pros and cons, and complications of the anterior-lateral extrapleural retroperitoneal approach for unstable (TLICS>4) thoracolumbar fractures.

PATIENTS AND METHODS

Clinical and radiological data and outcomes from a cohort treated surgically via said approach were retrospectively reviewed. All patients were operated on exclusively by 5 neurosurgeons trained in spine surgery.

RESULTS

Between June 1999 and December 2015, 86 patients underwent surgery (median age 42years, most common level: L1). Approximately 32.5% presented with a preoperative neurological defect. After surgery (mean duration: 275minutes), 75.6% presented with no neurological sequelae and only one-third required blood transfusion. Median postoperative stay was 7days. Correction of kyphosis was considered adequate and suboptimal but acceptable in 91% and 9% of the patients, respectively. Complications occurred in 36 patients, the majority being transient. We observed failure of the construct in 2 cases (collapse of an expandable cage and extrusion of a locking screw). No infections, vascular or visceral lesions, permanent neurological worsening or mortality occurred during hospitalisation. One patient ultimately needed additional posterior fixation due to persistence of pain. Median follow-up was 252days (27.9% was lost to follow-up).

CONCLUSIONS

The extrapleural extraperitoneal approach provides solid anterior reconstruction, allows wide decompression of the spinal canal, and permits adequate and long-lasting correction of kyphosis. The rates of infection, construct failure, need for reoperation and vascular or visceral lesions are minimal.