Surgical management and clinical outcomes of multiple-level symptomatic herniated thoracic discs

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.

Evolution of Thoracic Disc Herniation Surgery: Future Perspectives from a Systematic Review and Meta-Analysis

BACKGROUND

The neurosurgical treatment of thoracic disc herniation (TDH) has undergone dramatic changes over the years in terms of surgical approaches and intraoperative technological tools. There is still no unanimous consent on the criteria for approach selection, and the choice varies among Institutions. The aim of this study is to compare anterior and posterolateral approaches for TDH in terms of functional and surgical outcomes.

METHODS

A systematic literature review and meta-analysis according to PRISMA guidelines from EMBASE, PubMed, Cochrane Library, Web of Science, and Google Scholar online databases up to May 2024 incorporated studies that reported outcomes of thoracic disc herniation surgeries. Analyzed factors included major peri- and postoperative complications, intraoperative blood loss, hospital stay, neurological improvement, and complete hernia resection. Random-effect models were used to calculate pooled odds ratios and mean differences.

RESULTS

The posterolateral approach was associated with significantly lower rates of major medical (OR 0.14, 95% CI: 0.07 to 0.27) and surgical complications (OR 0.61, 95% CI: 0.38 to 0.99) compared to the anterior approach. Additionally, posterolateral approaches reduced intraoperative blood loss and shorter hospital stays. Posterolateral techniques were linked to higher odds of neurological improvement (OR 0.65, 95% CI: 0.43 to 0.99) and higher rates of complete hernia resection (OR 0.38, 95% CI: 0.21 to 0.71).

CONCLUSIONS

Posterolateral approaches offer advantages in terms of safety, recovery, neurological improvement, and complete hernia resection. More extensive prospective studies are needed to confirm these findings and refine surgical strategies. Emerging technologies, such as the exoscope and 45° endoscopy, may further enhance surgical outcomes.

Reliability of a Novel Classification System for Thoracic Disc Herniations

STUDY DESIGN

This is a cross-sectional survey.

OBJECTIVE

The aim was to assess the reliability of a proposed novel classification system for thoracic disc herniations (TDHs).

SUMMARY OF BACKGROUND DATA

TDHs are complex entities varying substantially in many factors, including size, location, and calcification. To date, no comprehensive system exists to categorize these lesions.

METHODS

Our proposed system classifies 5 types of TDHs using anatomic and clinical characteristics, with subtypes for calcification. Type 0 herniations are small (≤40% of spinal canal) TDHs without significant spinal cord or nerve root effacement; type 1 are small and paracentral; type 2 are small and central; type 3 are giant (>40% of spinal canal) and paracentral; and type 4 are giant and central. Patients with types 1 to 4 TDHs have correlative clinical and radiographic evidence of spinal cord compression. Twenty-one US spine surgeons with substantial TDH experience rated 10 illustrative cases to determine the system's reliability. Interobserver and intraobserver reliability were determined using the Fleiss kappa coefficient. Surgeons were also surveyed to obtain consensus on surgical approaches for the various TDH types.

RESULTS

High agreement was found for the classification system, with 80% (range 62% to 95%) overall agreement and high interrater and intrarater reliability (kappa 0.604 [moderate to substantial agreement] and kappa 0.630 [substantial agreement], respectively). All surgeons reported nonoperative management of type 0 TDHs. For type 1 TDHs, most respondents (71%) preferred posterior approaches. For type 2 TDHs, responses were roughly equivalent for anterolateral and posterior options. For types 3 and 4 TDHs, most respondents (72% and 68%, respectively) preferred anterolateral approaches.

CONCLUSIONS

This novel classification system can be used to reliably categorize TDHs, standardize description, and potentially guide the selection of surgical approach. Validation of this system with regard to treatment and clinical outcomes represents a line of future study.

Evaluation of clinical outcomes, complication rate, feasibility, and applicability of transfacet pedicle-sparing approach in thoracic disc herniation: a systematic review and meta-analysis

OBJECTIVE

This study aimed to evaluate the clinical outcomes, complication rate, feasibility, and applicability of transfacet pedicle-sparing approach for treating thoracic disc herniation.

METHODS

We searched three databases including the Cochrane Library, PubMed, and Embase for eligible studies until Dec 2022. The quality of studies and their risk of bias were assessed using the methodological index for non-randomized studies. We evaluated the heterogeneity between studies using the I² statistic and the P-value for the heterogeneity.

RESULTS

A total of 328 patients described in 11 included articles were published from 2009 to 2022. Pain outcomes using the visual analog scale (VAS score) were reported in four studies. The standardized mean difference was reported as 0.749 (CI 95% 0.555-0.943). The obtained result showed the positive effect of the procedure and the improvement of patients' pain after the surgery. Myelopathy outcomes using the Nurick score were reported in five studies. The standardized mean difference was reported as 0.775 (CI 95% 0.479-1.071). The result showed the positive effect of the procedure. Eight studies assessed postoperative complications and neurological deterioration. The pooled overall complication was 12.4% (32/258) and 3.5% (9/258) neurological worsening.

CONCLUSION

The results of this study demonstrated a positive effect of the transfacet pedicle-sparing approach on the clinical outcomes of patients with thoracic disc herniation surgery. The technique has been shown to be safe and effective for the right patient. The technique is associated with lower rates of complications and a shorter hospital stay compared to other surgical approaches. This information can assist clinicians in making informed decisions when selecting the most appropriate surgical technique for their patients with thoracic disc herniation.

Research of a Safe and Simplified Intertransverse Process Approach for the Lower Thoracic Interbody Surgery

Objective

To assess a safe surgical approach for intertransverse process lower thoracic intervertebral body fusion (ITIF) based on measurements from enhanced three‐dimensional CT reconstruction, cadaver simulated operation, and patient operation.

Methods

Enhanced three‐dimensional CT image reconstruction was performed for 20 healthy volunteers on thoracic segments T8–T12. The length of the transverse process (LTP), distance between the upper and lower transverse processes (DULTP), remote distance of the transverse process (RDTP), height of the extraforaminal intervertebral space (HEIS), and oblique diameter of the intervertebral space (ODIS) were measured and recorded. The blood vessels of the intertransverse lower thoracic region were observed, and their internal diameters were measured. The rib‐intervertebral space relationship for T10/11 and T11/12 was measured in 104 patients of the thoracic skeleton. Then, based on the data from the CT measurements, simulated surgery was performed on six human cadavers at the T11/12 level. An ankylosing spondylitis (AS) patient with a fracture of the T10/11 level was eventually operated on with the ITIF technique.

Results

No significant difference was found between the lengths of the left and right thoracic transverse processes. The relationship of the values of the LTP and RDTP for the measured vertebrae were found to be as follows:T8 > T9 > T10 > T11 > T12. For HEIS and DULTP, T8–9 < T9–10 < T10–11 < T11–12. The results for the ODIS were as follows: T8–T9 < T9–T10 < T10–T11 < T11–T12. The blood vessel inner diameter of T11–12 was less than that of T10–11, while there was no significant difference between the diameters for T8–9 and T11–12. Almost half of the volunteer's T10/11 intervertebral spaces were covered posteriorly by the 11th rib (45.19% on left and 41.35% on right), while for most patients, the T11/12 intervertebral space was not covered by the 12th rib (98.08%). According to the cadaver experiments, intervertebral bone grafting and ipsilateral pedicle screw fixation were performed to simulate the operation. One patient with a combined AS and T10/11 fracture was then operated on with the ITIF technique and followed up for 3 years with satisfactory results.

Conclusion

As verified by 3D CT reconstruction measurements, cadaver simulation surgery and patient operation with follow‐up, the intertransverse process approach for some T10/T11 and almost all T11/T12 segments is a safe surgical pathway for operations such as ITIF, fracture bone grafting, clearance of focal lesions.

Phase I 270° single-incision percutaneous spinal endoscopy for decompression treatment of thoracic spinal stenosis

This study aimed to explore the feasibility of Phase I percutaneous spinal endoscopy with a 270° single incision in the ventral and dorsal dura mater for decompression treatment of thoracic spinal stenosis (TSS). Phase I percutaneous spinal endoscopy with a two-path (posterior and posterolateral approaches) single incision with a 270° decompression was performed in four cases of TSS with compression in the ventral and dorsal dura mater. The affected intervertebral space was located during the surgery, and the ossified ligamentum flavum in the ventral and dorsal dura mater was removed via laminectomy, which formed a decompression space in the thoracic cord. Next, posterolateral transforaminal expansion and plasty were performed to remove the ventral intervertebral disk. The visual analogue scale (VAS) score, thoracic spinal cord function score of the Japanese Orthopaedic Association (JOA) (11-point method), and Oswestry Disability Index (ODI) scores were used to evaluate the clinical efficacy. No dura mater or thoracic nerve injury occurred during the surgery. The symptoms of weakness in the lower extremities improved after the surgery. The postoperative magnetic resonance imaging and computed tomography examinations showed compression removal and dura mater bulging. The postoperative VAS, JOA, and ODI scores improved compared with the preoperative scores. Two surgical trajectories, posterior and posterolateral approaches, were established by a single incision using thoracic spinal canal decompression with Phase I 270° single-incision percutaneous spinal endoscopy. The posterior approach was performed mainly by translaminar unilateral fenestration and bilateral decompression in the ventral and dorsal dura mater, whereas the posterolateral approach was performed by decompression in the ventral dura mater to the midline of the vertebrae. This surgical method could be applied as a safe and feasible minimally invasive treatment for TSS with compression on both the ventral and dorsal dura mater.

Lower Neurological Risk with Anterior Operations Compared to Posterior Operations for Thoracic Disc Herniations: Analysis of 697 Patients

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Compare rates of postoperative neural deficits between surgical approaches for thoracic disc herniations (TDHs).

SUMMARY OF BACKGROUND DATA

Anterior and posterior approaches for TDH carry high reported neurological risk, albeit comparative risk is not well defined.

METHODS

Health Care Utilization Project (HCUP) state inpatient databases (NY, FL, CA; 2005-2014) were queried for patients who underwent TDH operation. Demographics, operative details, surgical approach, neural injury, length of stay (LOS), and discharge location were assessed. Multivariate linear regression was used to determine relative risk of neural deficit and skilled nursing facility (SNF) discharge.

RESULTS

Six hundred ninety-seven patients (mean age 52.0 yrs, 194 institutions) met inclusion. Majority of operations were elective (76.0%) and one to two levels (80.5%). Overall neural injury rate was 9.0%. Anterior operations had significantly lower rates of neural injury compared with posterior operations on univariate analysis (4.6% vs. 11.4%; P < 0.01). All multilevel operations had similarly high rates of neural injury. On multivariate analysis, posterior approaches (RR 1.78; P = 0.12) and combined approaches (RR 2.15; P = 0.17) had higher neural risk compared with anterior approaches after controlling for younger age, higher Charlson Comorbidity Index, and nonelective admissions. Combined approaches had similar neural injury rates (13.8%) to posterior operations (11.4%) and significantly longer LOS and SNF discharges compared with single approaches. Neural deficit was associated with discharge to SNF (With = 87.3%; Without = 23.7%; P < 0.01) and increased LOS (With = 12.5 days; Without = 6.9 days; P < 0.01).

CONCLUSION

Overall rate of neural deficit after operation for TDH was 9.0%. While anterior approach was associated with a lower neural injury rate, this association was confounded by age, Charlson Comorbidity Index, and admission type. After correcting for these confounders, a nonsignificant trend remained that favored the anterior approach. Neural deficit was associated with increased LOS and discharge to SNF postoperatively.Level of Evidence: 4.

Posterior Minimally Invasive Transpedicular Approach for Giant Calcified Thoracic Disc Herniation

STUDY DESIGN

Retrospective case series.

OBJECTIVE

Posterior surgery for thoracic disc herniation was associated with increased morbidity and mortality and new minimally invasive approaches have been recommended for soft disc herniation but not for calcified central disc. The objective of this study is to describe a posterolateral microscopic transpedicular approach for central thoracic disc herniation.

METHODS

This is a single center retrospective review of all the cases of giant thoracic calcified disc herniation as defined by Hott et al. Presence of myelopathy, percentage of canal compromise, T2 hypersignal, ASIA score, and ambulatory status were recorded. This posterolateral technique using a tubular retractor was thoroughly described.

RESULTS

Eight patients were operated upon with a mean follow-up of 16 months. Mean canal compromise was 61%. Mean operative time was 228 minutes and mean operative bleeding was 250 mL. There were no cases of dural tear or neurologic degradation.

CONCLUSION

This is the first report of posterior minimally invasive transpedicular approach for giant calcified disc herniation. There were neither cases of neurological deterioration nor increased rate of dural tears. This technique is thus safe and could be recommended for treatment of this rare disease.

Bilateral thoracic disc herniation with abdominal wall paresis: a case report

We present a rare case of a patient initially presenting with unilateral abdominal wall bulging and radicular pain caused by a lateral disc herniation at Th11/12, later suffering from a hernia recurrence with bilateral disc prolapse and motor deficits. The patient underwent sequesterectomy via a right hemilaminectomy at Th11, and after 8 weeks, a bilateral sequesterectomy with semirigid fusion Th11/12 was performed. Unilateral motor deficits at the thoracic level have been discussed in case reports; a bilateral disc protrusion with abdominal wall bulging occurring as a recurrent disc herniation has never been described before.

Trans-thoracic versus retropleural approach for symptomatic thoracic disc herniations: comparative analysis of 94 consecutive cases

PURPOSE

The authors illustrate their results in the surgical treatment of symptomatic thoracic disc herniations (TDHs) by comparing the traditional open to the less invasive retropleural lateral approaches.

METHODS

Retrospective review of 94 consecutive cases treated at a single Institution between 1988 and 2014. Fifty-two patients were males, 42 females, mean age was 53.9 years. Mean follow-up was 46.9 months (12-79 months). 33 patients were diagnosed with a giant thoracic disc herniation (GTDH). Upon admission, the most common symptoms were: motor impairment (91.4%, n = 86), neuropathic radicular pain with VAS > 4 (50%), bladder and bowel dysfunction (57.4% and 41.4% respectively) and sensory disturbances (29.7%). The surgical approach was based upon level, laterality and presence or absence of calcified lesions.

RESULTS

Decompression was performed in 7 cases via a thoraco-laparo-phrenotomy and in 87 cases via an antero-lateral thoracotomy. Out of the latter cases, 49 (56%) were trans-thoracic trans-pleural approaches (TTA) and 38 (44%) were less invasive retropleural approaches (MIRA). At follow-up, there were 59.5% neurologically intact patients according to the McCormick Scale, while 64.8% and 67% had no bladder or bowel dysfunction respectively. Complications occurred in 24 patients (25.5%). Pulmonary complications were the commonest (12.7%) with pleural effusion being significantly more common in patients treated with TTA compared to MIRA (20% vs 5.2%: X² 4.13 P:0.042). Severe post-operative neuralgia (VAS 7-10) was also significantly more frequent in the TTA group (22.4% vs 2.6% X² 7.07 p 0.0078).

CONCLUSIONS

MIRA is a safe and effective technique to obtain adequate TDH decompression and is associated with lower morbidity compared to TTA.

Evaluation of Cost-Utility of Thoracic Interlaminar Epidural Injections

PURPOSE OF REVIEW

Chronic thoracic pain, even though not as prevalent as low back and neck pain, appears in approximately 30% of the general population. The severity of thoracic pain and degree of disability seems to be similar to other painful conditions. Despite this severity, interventions in managing chronic thoracic pain are less frequent, and there is a paucity of literature regarding epidural injections and facet joint interventions.

RECENT FINDINGS

As with lumbar and cervical spine, a multitude of interventions are offered in managing chronic thoracic pain, including interventional techniques with epidural injections and facet joint interventions. A single randomized controlled trial (RCT) has been published with a 2-year follow-up of clinical effectiveness of the results. However, there have not been any cost-utility analysis studies pertaining to either epidural injections or facet joint interventions in thoracic pain. Based on the results of the RCT, a cost-utility analysis of thoracic interlaminar epidural injections was undertaken. Evaluation of the cost-utility analysis of thoracic interlaminar epidural injections with or without steroids in managing thoracic disc herniation, thoracic spinal stenosis, and thoracic discogenic or axial pain was assessed in 110 patients with a 2-year follow-up. Direct payment data from 2018 was utilized for procedural costs and indirect costs. Costs, including drug costs, were determined by multiplication of direct procedural payment data by a factor of 1.67 or addition of 40% of cost to accommodate for indirect payments and arrive at overall costs. Cost-utility analysis showed direct procedural cost of USD $1943.19, whereas total estimated costs year per QALY were USD $3245.12.

A Novel, Minimally Invasive Hybrid Technique to Approach Intracanal Herniated Thoracic Discs

BACKGROUND

Multiple options exist for thoracic disc herniation (TDH). However, when a specific technique is chosen, the goal is to avoid the manipulation of the spinal cord, which is already compressed.

OBJECTIVE

To describe a hybrid endoscopic technique for intracanal TDH by combining an oblique paraspinal approach (OPA) and transforaminal full-endoscopic discectomy.

METHODS

We describe the step-by-step operative technique and present the clinical and radiological outcomes of a case series of hybrid endoscopic thoracic discectomy.

RESULTS

A total of 3 patients were treated. We observed the usefulness of an OPA to enlarge the intervertebral foramen through the rigid tubular retractor and the feasibility of a full-endoscopic transforaminal approach to reach intracanal TDHs.

CONCLUSION

Early experience with the hybrid endoscopic technique for TDHs demonstrated acceptable clinical and radiological outcomes in the 3 patients treated; however, a larger sample size and a methodologically advantageous study to compare this procedure with conventional options are necessary to probe the full benefits of the hybrid technique.

Revision surgery in thoracic disc herniation

PURPOSE

Surgical treatment failures or strategies for the reoperation of residual thoracic disc herniations are sparsely discussed. We investigated factors that led to incomplete disc removal and recommend reoperation strategies.

METHODS

As a referral centre for thoracic disc disease, we reviewed retrospectively the clinical records and imaging studies before and after the treatment of patients who were sent to us for revision surgery for thoracic disc herniation from 2013 to 2018.

RESULTS

A total of 456 patients were treated from 2013 to 2018 at our institution. Twenty-one patients had undergone previously thoracic discectomy at an outside facility and harboured residual, incompletely excised and symptomatic herniated thoracic discs. In 12 patients (57%), the initial symptoms that led to their primary operation were improved after the first surgery, but recurred after a mean of 2.8 years. In seven patients (33%) they remained stable, and in two cases they were worse. All patients were treated via all dorsal approaches. In all 21 cases, the initial excision was incomplete regarding medullar decompression. All of the discs were removed completely in a single revision procedure. After mean follow-up of 24 months (range 12-57 months), clinical neurological improvement was demonstrated in seven patients, while three patients suffered a worsening and 11 patients remained stable.

CONCLUSION

Our data suggest that pure dorsal decompression provides a short relief of the symptoms caused by spinal cord compression. Progressive myelopathy (probably due to mechanical and vascular deficits) and scar formation may cause worsening of symptoms. These slides can be retrieved under Electronic Supplementary Material.

Clinical Features of Thoracic Myelopathy: A Single-Center Study

Thoracic myelopathy is relatively uncommon because few degenerative changes occur as a result of the restricted range of motion surrounding the rib cage.

Complications Associated with Surgery for Thoracic Disc Herniation: A Systematic Review and Network Meta-Analysis

BACKGROUND

A systematic review and network meta-analysis (Prospero ID CRD42018106936) were performed.

OBJECTIVE

The selection of the appropriate surgical approach for the management of thoracic disc herniation (TDH) is often challenging because of the frequency and variability of the associated complications. We evaluated the safety of the surgical approaches for TDH by estimating the mortality (Q1) and morbidity (Q2), and frequency of the most common complications (Q3).

METHODS

We searched the medical literature for randomized controlled trials and observational studies reporting on the management of TDH. Postoperative complications were the outcome of interest. The absolute and relative risk estimates, along with the rank probability scores, were estimated for each approach, through a network meta-analysis. The results were read in the light of the quality of the available evidence.

RESULTS

Fifteen studies with a total of 1036 patients fulfilled our eligibility criteria. Three deaths were reported. The overall morbidity was as high as 29%, largely attributed to medical (21%; 95% confidence interval [CI], 10%-38%), surgical site (11%; 95% CI, 5%-22%), cerebrospinal fluid-related (8%; 95% CI, 3%-8%), and neurologic complications (5%; 95% CI, 1%-24%). The anterior and lateral approaches were associated with a higher risk for medical and surgical complications compared with the posterolateral approach.

CONCLUSIONS

Surgery for TDH is associated with minimal mortality but significant morbidity, with large variations among the available approaches. An understanding of the perioperative complications rates is important to develop complication avoidance strategies and to aid accurate patient-to-doctor communication.

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.

Circumferential dural resection technique and reconstruction for the removal of giant calcified transdural herniated thoracic discs

OBJECTIVE

The authors report a novel paradigm for resection of the disc or dural complex to treat giant calcified transdural herniated thoracic discs, and they describe a technique for the repair of dural defects. These herniated thoracic discs are uncommon, complicated lesions that often require a multidisciplinary team for effective treatment. The intradural component must be removed to effectively decompress the spinal cord. The opening of the friable dura mater, which frequently adheres to the extradural component of the disc, can result in large defects and difficult-to-manage CSF leaks.

METHODS

The authors performed a retrospective study of the technique and outcomes in patients with a transdural herniated disc treated at St. Joseph’s Hospital and Medical Center within a 4-year period between 2012 and 2015.

RESULTS

During the study period, 7 patients (mean age 56.1 years) presented to the department of neurosurgery with clinical symptoms consistent with myeloradiculopathy. In all cases, 2-level corpectomies of the involved levels were combined with circumferential resection of the dura and complete decompression of the spinal cord. The dural defect was repaired with an onlay dural patch, and a large piece of AlloDerm (LifeCell Corp) graft was sewn to close the pleural defect. Every patient had a perioperative lumbar drain placed for CSF diversion. No patient suffered neurological decline related to the surgery, and 3 patients experienced clinically significant improvement in function. Two patients developed an early postoperative CSF leak that required operative revision to oversew the defects.

CONCLUSIONS

This novel technique for decompression of the spinal cord by dural resection for the removal of giant calcified transdural herniated thoracic discs is safe and results in excellent decompression of the spinal cord. The technique becomes necessary when primary repair of the dura is not possible, and it can be used in cases in which the resection of pathology includes the dura.

Surgical Approaches for the Treatment of Thoracic Disk Herniation: Results of a Decision Analysis

STUDY DESIGN

A decision analysis.

OBJECTIVE

To perform a decision analysis utilizing postoperative complication data, in conjunction with health-related quality of life (HRQoL) utility scores, to rank order the average health utility associated with various surgical approaches used to treat symptomatic thoracic disk herniation (TDH).

SUMMARY OF BACKGROUND DATA

Symptomatic TDH is an uncommon entity accounting for <1% of all symptomatic herniated disks. A variety of surgical approaches have been developed for its treatment, which may be classified into 4 major categories: open anterolateral transthoracic, minimally invasive anterolateral thoracoscopic, posterior, and lateral. These treatments have varying risk/benefit profiles, but there is still no set algorithm for choosing an approach in cases with multiple surgical options.

METHODS

We searched Medline, EMBASE, and the Cochrane Library for relevant articles on surgical approaches for TDHs published between 1990 and August 2014. Pooled complication data and HRQoL utility scores associated with each complication were evaluated using standard meta-analytic techniques to determine which surgical approach resulted in the highest average HRQoL.

RESULTS

Posterior surgical approaches resulted in the highest average HRQoL, followed by thoracoscopic, lateral, and finally open anterolateral transthoracic procedures. The higher average HRQoL associated with posterior approaches over all others was highly significant (P<0.001); conversely, the open anterolateral approach resulted in a lower average postoperative utility compared with all other approaches (P<0.001).

CONCLUSIONS

The results of this decision analysis favor posterior over lateral approaches, and thoracoscopic over open anterolateral approaches for the treatment of symptomatic TDHs, which may guide surgeons in cases where multiple surgical options are feasible. Future studies, such as randomized clinical trials, are necessary to ascertain whether novel surgical strategies have risk/benefit profiles that ultimately supersede those of traditional approaches, and whether enough cases are encountered by the average surgeon to justify their adoption.

The incidence and risk factors of postoperative neurological deterioration after posterior decompression with or without instrumented fusion for thoracic myelopathy

The aim of this study was to explore the incidence and risk factors of postoperative neurological deterioration after posterior decompression with or without instrumented fusion for thoracic myelopathy, and hope to provide references in decision-making and surgical planning for both spinal surgeon and thoracic stenosis patients.By retrieving the medical records from January 2001 to November 2015, 168 patients were retrospectively reviewed. According to the occurrence of postoperative neurological deterioration, patients were divided into 2 groups: neurological deterioration (ND) group and non-ND group. To investigate risk values for the occurrence of ND, 3 categorized factors were analyzed statistically: patient characteristics-preoperative data of age, sex, body mass index, bone mineral density, the duration of disease (from first symptoms to operation), the preoperative neurological function (Frankel grade), and diagnosis; surgical variables-surgery time, the amount of bleeding, mean arterial pressure, intervertebral fusion or not, and instrumentation or not; radiographic parameters-the spinal canal occupancy ratio, location of the lesion, thoracic kyphosis, and kyphosis correction.Postoperative neurological deterioration was developed in 23 of 168 patients (13.7%), and were enrolled as ND group. There was no statistically significant difference between the 2 groups in age at operation, sex composition, body mass index, and bone mineral density. The preoperative diagnosis presented significant difference between the 2 groups, because ossification of posterior longitudinal ligament combined with ossification of the ligamentum flavum was more common in ND group, whereas ossification of the ligamentum flavum alone was more common in non-ND group. There was no difference between the 2 groups in mean surgery time, the incidence of intraoperative direct trauma, and the number of patients that received instrumentation. The mean bleeding was much more in ND group than that in non-ND group, and the mean arterial pressure was lower in ND group than that in non-ND group. Also, the mean spinal canal occupancy ratio was more severe in ND group than that in non-ND group. There were no statistically significant difference between the 2 groups in stenosis location and preoperative thoracic kyphosis. The mean kyphosis correction was more significant in ND group. When included in a multivariate logistic regression model, thoracic disc herniation + ossification of posterior longitudinal ligament, spinal canal occupancy ratio more than 70%, bleeding more than 800 mL, and mean arterial pressure less than 81 mm Hg were independently associated with the postoperative neurological deterioration.In conclusion, ossification of posterior longitudinal ligament combined with ossification of the ligamentum flavum, spinal canal occupancy ratio more than 70%, intraoperative bleeding more than 800 mL, and mean arterial pressure less than 81 mm Hg are risk factors for the occurrence of postoperative neurologic deterioration. Improving surgical technique, shortening operation time, and paying more attention to hemostasis could provide opportunities to reduce the incidence of neurologic deterioration and to improve therapeutic outcomes.

Indications and Techniques for Spinal Instrumentation in Thoracic Disk Surgery

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To identify the indications, techniques, and outcomes for instrumented fusion during thoracic discectomy.

SUMMARY OF BACKGROUND DATA

Thoracic discectomy may require extensive bone removal to avoid spinal cord manipulation, but the indications and techniques for instrumented fusion during thoracic discectomy remain poorly delineated.

METHODS

The authors identified 220 consecutive patients who underwent thoracic discectomy between 1992 and 2012. Clinical and radiographic variables were compared between patients who underwent instrumented fusion and patients without instrumentation, and among surgical approaches utilized for discectomy.

RESULTS

Patient age for the entire cohort averaged 49±13.01 years, and mean clinical follow-up was 45 months (range, 1-218 mo). Patients underwent 226 thoracic discectomy procedures, including 48 thoracotomy, 136 thoracoscopy, and 42 posterolateral approaches. Seventy-eight patients required instrumented fusion and, compared with patients without instrumentation, were more likely to present with myelopathy (P<0.0001) and harbor giant (P=0.0012), calcified (P=0.019), or transdural (P=0.0004) herniated disks. Surgery with instrumentation resulted in greater blood loss (P<0.0001), longer hospital stay (P<0.0001), and a higher complication rate (22% vs. 9.9%), yet patients in both cohorts had similar rates of symptom resolution postoperatively. Of the patients who underwent thoracic discectomy without instrumentation, 3 (2.1%) developed delayed deformity or instability and required subsequent surgery for fixation and fusion at an average 6.3 months postoperatively (range, 4-8 mo). Patients who underwent instrumented fusion exhibited no nonunions or delayed deformity.

CONCLUSIONS

Thoracic discectomy without fixation is a reasonable clinical option in carefully selected patients, but instrumented fusion is safe and effective in other patients. Indications for fixation and fusion are thus proposed.

En bloc resection of upper thoracic chordoma via a combined simultaneous anterolateral thoracoscopic and posterior approach

BACKGROUND

En bloc resection of chordomas is associated with increased patient survival. Achievement of en bloc resection, however, may present a great surgical challenge, particularly in the mobile spine. Novel multidisciplinary techniques may enable en bloc resection of lesions presenting in anatomically challenging locations. A combined simultaneous thoracoscopic and posterior approach in a patient with an upper thoracic chordoma is presented; en bloc resection was achieved.

OBJECTIVE

To show the feasibility, safety, and utility of performing a thoracoscopy-assisted en bloc resection of a chordoma involving the upper thoracic spine.

METHODS

A case study is presented of a patient with biopsy-proven chordoma of T2-3 with predominantly paravertebral involvement who underwent multilevel en bloc resection via a simultaneous combined anterolateral thoracoscopic and posterior approach. Thoracoscopic assistance achieved separation of the tumor and ventral spine from the adjacent mediastinal structures. En bloc resection proceeded without complication. The spine was stabilized with posterior instrumentation.

RESULTS

A multilevel en bloc resection was achieved with negative margins, preserving more than half of the remaining vertebral bodies and allowing short segment posterior fixation without extension into the cervical spine. The patient remained neurologically intact.

CONCLUSION

A combined simultaneous thoracoscopic and posterior approach is safe and effective for en bloc resection of multilevel chordoma involving the upper thoracic spine. This technique allows for a plane to be established ventrally between the tumor and the mediastinum, thus assisting with safe osteotomies via the posterior approach.