Combined anterior plus posterior stabilization versus posterior short-segment instrumentation and fusion for mid-lumbar (L2-L4) burst fractures

Radiologic Outcomes after Operative Management of Traumatic Spine Fractures: Stand-Alone Posterior Stabilization versus Combined Anteroposterior Approach

BACKGROUND

 Previous research emphasizes correcting deformities resulting from spine fractures by restoring sagittal alignment and vertebral height. This study aims to compare radiologic outcomes, including sagittal index (SI) and loss of vertebral body height (LVBH), between stand-alone posterior stabilization (group I) and the posteroanterior/combined approach (group II) in the operative management of traumatic thoracic or lumbar spine fractures.

METHODS

 In this retrospective single-center study, all patients with traumatic spine fractures (T1-L5) undergoing surgical stabilization between January 1, 2015, and May 31, 2021, were included. Two spine surgeons independently assessed imaging, recording the SI and LVBH values at baseline, after each surgical intervention, and during follow-up (at least 3 months posttreatment). The mean SI and LVBH values between the assessing surgeons were utilized. Linear mixed-effects regression models, adjusted to baseline values, compared the SI and the LVBH values between the two groups.

RESULTS

 In all, 71 patients (42 men), with the median age of 38 years (interquartile range [IQR]: 28-54) and median follow-up of 4 months (IQR: 3-17), were included. Thirty-two patients were in group I and 39 patients were in group II. Forty fractures included the thoracolumbar junction (T12 or L1), 15 affected the thoracic spine, and 14 the lumbar spine. The regression model revealed superior sagittal alignment in group II, with an adjusted mean difference for SI of -4.24 (95% confidence interval [CI]: -7.13 to -1.36; p = 0.004), and enhanced restoration of vertebral body height with an adjusted mean difference for LVBH of 0.11 in the combined approach (95% CI: 0.02-0.20; p = 0.02). Nine postoperative complications occurred in the entire cohort (4 in group I and 5 in group II).

CONCLUSIONS

 Combined posteroanterior stabilization for spine fractures improves deformities by enhancing sagittal alignment and increasing vertebral body height, with acceptable morbidity compared with the stand-alone posterior approach.

Contiguous Burst Fractures of the Lumbar Spine

Burst fractures of vertebrae are usually caused by high-energy axial compression force, mostly caused by fall from height or road traffic accidents. They frequently occur at the thoracolumbar junction mostly requiring surgery. Contiguous burst fractures involving multiple lumbar vertebrae are uncommon. This case is a male in his early 40s presented with low back pain and weakness of lower limbs following an injury sustained during a road traffic accident. Clinically, the patient had a bilateral foot drop. On radiological evaluation, he was diagnosed to have L3 and L4 burst fractures with spinal canal occlusion. He underwent posterior stabilization from L2-L5 and decompression at the L3-L4 level. At one-year follow-up, the patient was pain-free with complete neurological recovery. Contiguous lumbar spine burst fractures are very rare in occurrence. Though burst fractures are managed surgically to provide stability, the surgical approaches depend on the individual fracture pattern, degree of spinal canal occlusion, and neurological status.

Finite element analysis of different pedicle screw internal fixations for first lumbar vertebral fracture in different sports conditions

OBJECTIVE

Lumbar fractures are the most common spinal injuries, and surgery is required for severe fracture. This study aimed to investigate the variations in motion and stress in varying states of activity after minimally invasive and traditional open pedicle screw placement for L1 vertebral fracture stabilization.

METHODS

We studied a male volunteer (26 years old) with no history of chronic back pain or lumbar spine trauma. We used the finite element method for this investigation. Using finite element software, we created a three-dimensional model of L1 vertebral compression fracture. We also constructed models for four percutaneous pedicle screws spanning the fractured vertebra and four screws traversing the damaged vertebra with transverse fixation.

RESULTS

In all three-dimensional movement directions, the open pedicle fixation system experienced maximum stress higher than its percutaneous counterpart. With axial spinal rotation, von Mises stress on the traditional open pedicle screw was considerably lower than that with percutaneous pedicle fixation, but peak stress was elevated at the transverse connection. Traditional open pedicle fixation displayed less maximum displacement than percutaneous pedicle internal fixation.

CONCLUSIONS

During axial spinal movements, high peak stress is observed at the transverse connection. Patients should avoid excessive axial rotation of the spine during recovery.

Surgical treatment of traumatic fractures of the thoracic and lumbar spine: A systematic review

Introduction

The treatment of traumatic thoracic and lumbar spine fractures remains controversial. To date no consensus exists on the correct choice of surgical approach and technique.

Research question

to provide a comprehensive up-to-date overview of the available different surgical methods and their quantified outcomes.

Methods

PubMed and EMBASE were searched between 2001 and 2020 using the term 'spinal fractures'. Inclusion criteria were: adults, ≥10 cases, ≥12 months follow-up, thoracic or lumbar fractures, and surgery <3 weeks of trauma. Studies were categorized per surgical technique: Posterior open (PO), posterior percutaneous (PP), stand-alone vertebral body augmentation (SA), anterior scopic (AS), anterior open (AO), posterior percutaneous and anterior open (PPAO), posterior percutaneous and anterior scopic (PPAS), posterior open and anterior open (POAO) and posterior open and anterior scopic (POAS). The PO group was used as a reference group.

Results

After duplicate removal 6042 articles were identified. A total of 102 articles were Included, in which 137 separate surgical technique cohorts were described: PO (n = 75), PP, (n = 39), SA (n = 12), AO (n = 5), PPAO (n = 1), PPAS (n = 1), POAO (n = 2) and POAS (n = 2).

Discussion and conclusion

For type A3/A4 burst fractures, without severe neurological deficit, posterior percutaneous (PP) technique seems the safest and most feasible option in the past two decades. If needed, PP can be combined with anterior augmentation to prevent secondary kyphosis. Furthermore, posterior open (PO) technique is feasible in almost all types of fractures. Also, this technique can provide for an additional posterior decompression or fusion. Overall, no neurologic deterioration was reported following surgical intervention.

Finite element analysis of minimally invasive nail placement and traditional nail placement in the treatment of lumbar 1 vertebral compression fracture

Using the finite element analysis method to help us better understand the biomechanical changes of the spine after surgery and the changes in the stress distribution around the screw implantation area. The finite element model of L1 vertebral compression fracture was constructed by using a large number of finite element programs. On the fracture model, 2 kinds of internal fixation devices are set up, namely: the first type of 4 screws across the injured vertebra through the adjacent upper and lower vertebrae + transverse connector; the second type of 4 screws crosses the injured vertebra through the adjacent upper and lower vertebrae + non-transverse connector. To study the distribution of the maximum displacement and von Mises stress of the intramedullary pedicle screws and rods of the 2 types of internal fixation devices after implantation in the spine under certain loading conditions. In traditional open pedicle screw fixation, the maximum stress in the pedicle screw fixation system in the direction of 3D movement is higher than in percutaneous pedicle screw fixation. There is no significant difference in the Von Mises stress of the pedicle screw between the 2 procedures when the spine performs flexion-extension and lateral flexion activities. When the spine is rotating axially, the Von Mises stress of the pedicle screw in conventional open surgery is significantly less than that of the screw in percutaneous pedicle screw fixation. Traditional open internal fixation produces stress peaks of 891.7 MPa and 886.34 MPa at the transverse joint during axial rotation. Only when the spine is rotating in the axial direction, the maximum displacement of traditional open pedicle screw fixation is smaller than that of percutaneous pedicle screw fixation. There is no significant difference in the maximum displacement between the 2 procedures when the spine is moving in other directions. Traditional open pedicle screw fixation can strengthen the stability of the spine in the direction of axial rotation, and can also be greater to reduce the maximum stress of the pedicle screw axial rotation, so the clinical treatment of unstable fractures of the thoracolumbar spine instability is of great significance.

Clinical effect of limited posterior decompression and 13-mm titanium mesh implantation on severe thoracolumbar burst fractures: A case series

Background

Posterior incision with 270° spinal canal decompression and reconstruction surgery is a treatment option for thoracolumbar burst fractures (TLBF), but the large diameter titanium mesh placement is difficult. This study evaluated the characteristics and clinical effects of limited posterior decompression and 13-mm titanium mesh implantation to treat TLBF.

Hypothesis

13-mm titanium meshes could be used to fix thoracolumbar burst fractures.

Patients and methods

This case series included patients who underwent limited posterior decompression and 13-mm titanium mesh implantation at China Medical University Shaoxing Hospital (01/2015–12/2019). The Cobb angle, injury vertebral anterior edge height loss percentage, and spinal canal occupancy rate were analyzed. The degree of spinal cord injury was evaluated according to the ASIA grade.

Results

Fifteen patients were included (eight males and seven females). The patients were 32.2 ± 4.6 years of age. The American Association of Spinal Injury improved after surgery (A/B/C/D/E: from 2/6/5/2/0 to 0/0/2/8/5, P &lt; 0.001). The Cobb angle decreased after surgery (from 20.1 ± 4.8° to 7.1 ± 1.4°, P &lt; 0.001) but increased to 8.2 ± 0.9° at 1 year (P = 0.003). The percentage of loss of the anterior edge height of the injured vertebrae decreased after surgery (from 40.9% ± 6.1% to 7.5% ± 1.8%, P &lt; 0.001) and decreased at 1 year (7.0% ± 1.5%, P = 0.044). The spinal canal occupancy rate decreased after surgery (from 64.8% ± 7.8% to 20.1% ± 4.2%, P &lt; 0.001) but did not decrease further at 1 year (19.4% ± 3.4%, P = 0.166).

Discussion

Spinal canal limited posterior decompression, and 13-mm titanium mesh implantation in the treatment of TLBF can achieve one-stage spinal canal decompression and three-column reconstruction. The curative effect was satisfying.

Level of evidence

Level IV; case series.

THORACOLOMBAR BURST FRACTURES: SHORT FIXATION, WITHOUT ARTHRODESIS AND WITHOUT REMOVAL OF THE IMPLANT

Objectives

To present the functional outcomes, through the first case series in our country, of patients with thoracolumbar burst fractures (A3,A4), submitted to short posterior fixation, without arthrodesis and without removal of the implants, until the end of the minimum follow-up of one year.

Methods

Fifty five patients consecutively treated between January/2010 and January/2019 were evaluated through medical records and imaging exams. Radiographic analysis was performed by mea suring local and segmental kyphosis using the Cobb method. Functional assessment was analyzed using the non-specific SF-36 questionnaire and the 1983 Denis pain and work-specific questionnaire, applied after 12 months of follow-up.

Results

With a loss of five patients (9%), 22 (44%) patients reported having minimal and occasional pain and 8 (16%) patients reported having no pain. Three (6%) patients responded that they were completely incapacitated. Patients had a mean score of 73.16 points in the SF-36 domains. There was a significant reduction in kyphosis in 12 months (9.1±5.2 [min-max 0-22]) compared to the preoperative period (14.9±7.8 [min-max 0-32]) ( p≤0.01). One patient required implant removal due to the symptomatic prominence of the implant.

Conclusion

This case series suggests that the technique leads to satisfactory functional results, without implant failure or significant kyphosis after a minimum follow-up of 12 months of treatment. Evidence Level IV; Case series.

EVALUATION OF KYPHOSIS MEASUREMENT IN THORACOLUMBAR SPINE FRACTURES

ABSTRACT Objectives: Evaluate the reliability and reproducibility of the kyphosis measurement in thoracolumbar spine traumatic fractures by different assessment methods in different types of fractures. Methods: Fifteen fractures of the thoracolumbar spine, previously classified into types A, B, and C according to Magerl’s classification, were evaluated. The value of kyphosis was measured using five different methods: (1) Cobb angle; (2) Gardner’s method; (3) back wall method; (4) angle of adjacent endplates; and (5) wedge angle. The measurements were performed by five independent observers and repeated five times with a minimum interval of two weeks between each evaluation. Results: Intraobserver reliability was excellent among the five observers, evidencing good reproducibility of the methods. The five methods used also showed great intraobserver reliability in the global analysis, with methods one and four being more consistent. Conclusion: Although there is no universal agreement on measuring kyphosis in thoracolumbar fractures, our study concluded that method 1 (Cobb angle) and method 4 (adjacent endplate angle) presented the best interobserver reliabilities. Furthermore, the use of digitized radiographs and a simple computer program allowed the performance of highly reliable and reproducible measurements by all methods, given the high intraobserver reliability. Level of Evidence II; Comparative study.

The Efficiency and Reliability of Minimally Invasive Anterior Corpectomy and Percutaneous Posterior Stabilization for the Treatment of Unstable Thoracolumbar Burst Fractures

OBJECTIVE

The purpose of this study was to evaluate the radiological and clinical outcomes of minimally invasive anterior corpectomy and percutaneous posterior stabilization for treating unstable thoracolumbar burst fractures.

METHODS

Patients with unstable thoracolumbar burst fractures who underwent minimally invasive anterior corpectomy and percutaneous posterior stabilization between 2012 and 2019 at a tertiary hospital were enrolled. Radiological outcomes such as endplate subsidence and fusion status were identified on preoperative and postoperative plain radiographs and computed tomography images. Preoperative and postoperative neurological statuses were evaluated using the American Spinal Injury Association impairment scale. Furthermore, operation-related parameters were analyzed.

RESULTS

In total, 21 patients (mean follow-up period, 21.7 months) were included in this study. Of them, 17 (80.95%) patients exhibited complete fusion according to the Bridwell's criteria at the final follow-up, and only 1 patient exhibited nonunion at the surgical level. Endplate subsidence was observed in 6 (28.57%) patients; however, there were no definite symptoms that would have necessitated a revision surgery. Of 15 patients with preoperative neurological impairment, 7 exhibited neurological improvement during follow-up. None of the patients experienced postoperative neurological deterioration. Regarding operation-related parameters, the mean operative time and intraoperative blood loss were 266.19 ± 51.54 min and 520.71 ± 190.86 ml, respectively. The mean length of hospital stays and days to postoperative ambulation were 12.14 and 4.20 days, respectively.

CONCLUSIONS

Minimally invasive anterolateral corpectomy with percutaneous pedicle screw fixation is a reliable surgical treatment option for unstable thoracolumbar burst fractures.

Single-Stage Posterior Vertebral Column Resection With Circumferential Reconstruction for Thoracic/Thoracolumbar Burst Fractures With or Without Neurological Deficit: Clinical Neurological and Radiological Outcomes

STUDY DESIGN

Retrospective study.

OBJECTIVE

The aim of this study is to evaluate the clinical, neurological, and radiological outcomes of posterior vertebral column resection (PVCR) technique for treatment of thoracic and thoracolumbar burst fractures.

METHODS

Fifty-one patients (18 male, 33 female) with thoracic/thoracolumbar burst fractures who had been treated with PVCR technique were retrospectively reviewed. Preoperative and most recent radiographs were evaluated and local kyphosis angle (LKA), sagittal and coronal spinal parameters were measured. Neurological and functional results were assessed by the American Spinal Injury Association (ASIA) Impairment Scale, visual analogue scale score, Oswestry Disability Index, and Short Form 36 version 2.

RESULTS

The mean age was 49 years (range 22-83 years). The mean follow-up period was 69 months (range 28-216 months). Fractures were thoracic in 16 and thoracolumbar in 35 of the patients. AO spine thoracolumbar injury morphological types were as follows: 1 type A3, 15 type A4, 4 type B1, 23 type B2, 8 type C injuries. PVCR was performed in a single level in 48 of the patients and in 2 levels in 3 patients. The mean operative time was 434 minutes (range 270-530 minutes) and mean intraoperative blood loss was 520 mL (range 360-1100 mL). The mean LKA improved from 34.7° to 4.9° (85.9%). For 27 patients, the initial neurological deficit (ASIA A in 8, ASIA B in 3, ASIA C in 5, and ASIA D in 11) improved at least 1 ASIA grade (1-3 grades) in 22 patients (81.5%). Solid fusion, assessed with computed tomography at the final follow-up, was achieved in all patients.

CONCLUSION

Single-stage PVCR provides complete spinal canal decompression, ideal kyphosis correction with gradual lengthening of anterior column together with sequential posterior column compression. Anterior column support, avoidance of the morbidity of anterior approach and improvement of neurological deficit are the other advantages of the single stage PVCR technique in patients with thoracic/thoracolumbar burst fractures.

Surgical fixation of pathologic and traumatic spinal fractures using single position surgery technique in lateral decubitus position

STUDY DESIGN

Retrospective Case Series.

OBJECTIVES

This study aims to determine complications, readmission, and revision surgery rates in patients undergoing single position surgery (SPS) for surgical treatment of traumatic and pathologic thoracolumbar fractures.

METHODS

A multi-center review of patients who underwent SPS in the lateral decubitus position (LSPS) for surgical management of traumatic or pathologic thoracolumbar fractures between January 2016 and May 2020 was conducted. Operative time, estimated blood loss (EBL), intraoperative complications, postoperative complications, readmissions, and revision surgeries were collected.

RESULTS

A total of 12 patients with a mean age of 45 years (66.67% male) were included. The majority of patients underwent operative treatment for acute thoracolumbar trauma (66.67%) with a mean injury severity score (ISS) of 16.71. Mean operative time was 175.5 min, mean EBL of 816.67 cc. Five patients experienced a complication, two of which required revision surgery for additional decompression during the initial admission. All ambulatory patients were mobilized on postoperative day 1. The mean hospital length of stay (LOS) was 9.67 days.

CONCLUSION

The results of this case series supports LSPS as a feasible alternative to the traditional combined anterior-posterior approach for surgical treatment of pathologic and thoracolumbar fractures. These results are similar to reductions in operative time, EBL, and LOS seen in the elective spine literature with LSPS.

LEVEL OF EVIDENCE

IV.

Thoracolumbar Burst Fracture: McCormack Load-sharing Classification: Systematic Review and Single-arm Meta-analysis

STUDY DESIGN

A systematic review and single-arm meta-analysis of randomized clinical trials.

OBJECTIVE

The aim of this study was to evaluate whether the load-sharing classification (LSC) is reliable to predict the best surgical approach for thoracolumbar burst fracture (TBF).

SUMMARY OF BACKGROUND DATA

There is no previous review evaluating the efficacy of the use of LSC as a guide in the surgical treatment of burst fractures.

METHODS

On April 19th, 2019, a broad search was performed in the following databases: EMBASE, PubMed, Cochrane, SCOPUS, Web of Science, LILACS, and gray literature. This study was registered on the International Prospective Register of Systematic Reviews. We included clinical trials involving patients with TBF undergoing posterior surgical treatment, classified by load-sharing score, and that enabled the analysis of the outcomes loss of segmental kyphosis and implant failure (IF). We performed random- or fixed-effects models meta-analyses depending on the data homogeneity. Heterogeneity between studies was estimated by I2 and τ2 statistics.

RESULTS

The search identified 189 references, out of which nine studies were eligible for this review. All articles presenting LSC up to 6 proved to be reliable in indicating that only posterior instrumentation is necessary, without screw failures or loss of kyphosis correction. For cases where the LSC was >6, only 2.5% of the individuals presented IF upon posterior approach alone. For loss of kyphosis correction, only 5% of patients had this outcome where LSC >6. For both outcomes together, we had 6% of postoperative problems (I2 = 77%, τ2 < 0.0015, P < 0.01).

CONCLUSION

Load-sharing scores up to 6 are 100% reliable, only requiring posterior instrumentation for stabilization. For scores >6, the risk of implant breakage and loss of kyphosis correction in posterior fixation alone is low. Thus, other factors should be considered to define the best surgical approach to be adopted.Level of Evidence: 1.

Managing Incomplete and Complete Thoracolumbar Burst Fractures (AO Spine A3 and A4). Results from a Prospective Single-Center Study Comparing Posterior Percutaneous Instrumentation plus Mini-Open Anterolateral Fusion versus Single-Stage Posterior Instrumented Fusion

OBJECTIVE

The treatment strategy for thoracolumbar burst fractures is still debated. The aim of this study is to evaluate clinical and radiologic outcomes of a 2-stage strategy with immediate posterior percutaneous instrumentation and delayed anterolateral fusion (group A) versus a single-stage open posterior instrumented fusion (group B).

METHODS

Demographics and clinical and surgical data of patients operated for AO Spine A3 and A4 fractures were prospectively collected. Vertebral height and deformity were evaluated before and after surgery. Visual analog scale score for back pain, Oswestry Disability Index, and 12-Item Short Form Health Survey results for quality-of-life assessment were collected during follow-up.

RESULTS

Among the 110 patients enrolled, 66 were allocated to group A and 44 to group B; the most common fractured level was T12 (34%). Postoperative complications were higher in group B, especially the wound infection rate (18% vs. 3%), and pseudomeningocele (14% vs. 0%). The 2-stage approach allowed an average long-term gain of 15.8° at the local kyphosis of fractured vertebra and 5.8° at the regional level (Cobb angle), versus 15.4° and 5.5° in group B. At 2 years follow-up, both groups showed significant functional improvements; however, the visual analog scale and Oswestry Disability Index metrics seemed more favorable for group A patients (P < 0.0001 vs. P < 0.003). A complete fusion rate was obtained in 100% of group A vs. 65% of group B.

CONCLUSIONS

Our study indicates that percutaneous instrumentation and anterior fusion or an expandable cage lead to excellent long-term clinical and radiologic outcomes with a lower complication rate and higher fusion rate than those of open posterior approaches.

A Rare Case of Contiguous Three-level Lumbar Burst Fractures-treated with Combined Posterior Stabilization and Anterior Fusion

Introduction:

Burst fractures occur frequently in high energy trauma and are commonly associated with falls from height and road traffic accidents. While multiple burst fractures are not uncommon in thoracic spine, three or more contiguous level burst fractures are a relative rarity especially, in lumbar spine. The treatment of multilevel burst fractures must be individualized, and each fracture should be treated according to its inherent stability. To the best of our knowledge, this is the only case of such injury reported in English literature.

Case Report:

A 17-year-old girl who sustained contiguous three-level lumbar burst fractures with neurological compromise following alleged history of fall from height. Radiographs/computed tomography scan revealed burst fractures of L2, L3, and L4 vertebrae with retropulsion of bony fragments at all the levels. Patient underwent minimally invasive posterior stabilization and anterior Hemi-corpectomy of L2, L4, and fusion. The patient recovered completely from neurological deficits by the end of 6 months.

Conclusion:

Multiple contiguous burst fractures in the lumbar spine are a rare entity. To the best of our knowledge, this is the only case of such injury reported in English literature. The treatment requires a thorough assessment of the fracture pattern and often requires a combination of surgical approaches. Each fracture merits treatment based on individual characteristics of fracture patterns and the amount of canal compromise at each level.

Long-term results after thoracoscopic anterior spondylodesis with or without posterior stabilization of unstable incomplete burst fractures of the thoracolumbar junction: a prospective cohort study

Background

Minimally invasive, thoracoscopic anterior spondylodesis (MIAS) is an established treatment for burst fractures of the thoracolumbar spine. Good restoration of the local sagittal alignment and good functional results have been reported. The aim of this study was to evaluate long-term results of MIAS in patients with incomplete burst fractures and to analyze the influence on global sagittal alignment, clinical outcomes, and adjacent segment degeneration.

Methods

From 2002 to 2003, 18 patients were treated with MIAS for incomplete thoracolumbar burst fractures. Mono-segmental spondylodesis was performed with an iliac crest bone graft and bisegmental spondylodesis with a titanium cage. In this single-center prospective cohort study, 15 patients were available for follow-up (FU) after an average of 12.9 years (12.1–14.4). Seven patients were treated with a combined anterior and posterior instrumentation and eight patients with anterior spondylodesis only. The primary clinical outcome parameter was the Oswestry Disability Index (ODI); secondary parameters were the Short Form 36 (SF36) and the visual analog scale (VAS spine). Full spine radiographs were assessed for bisegmental Cobb angle, alignment parameters, and signs of adjacent segment degeneration (ASD).

Results

ODI evaluation showed a mean impairment of 11.7% with minimal limitations in 13 patients. Neither a significant deterioration over time nor significant differences between both therapy strategies were found in the clinical scores at the latest follow-up. The mean bisegmental increase of regional malalignment of reduction was 8.8° (± 7.3°) with no significant correlation to any clinical outcome scores. The majority of patients had no signs of adjacent segment degeneration. Two patients showed minor radiologic changes. All patients had a balanced sagittal spine profile.

Conclusions

In conclusion, MIAS leads to good clinical results with—in majority—minimal spine-related impairment at the latest follow-up. No significant deterioration at 12-year FU was detectable compared to the 6-year results for the SF36 and VAS spine scores. There was no association between sagittal alignment, clinical outcome scores, and ASD.

Trial registration

The study was retrospectively registered in the German Clinical Trials Register (Nr.00015656).

Reliability and Validity of the English Version of the AOSpine PROST (Patient Reported Outcome Spine Trauma)

STUDY DESIGN

Multicenter validation study.

OBJECTIVE

The aim of this study was to translate and adapt the AOSpine PROST (Patient Reported Outcome Spine Trauma) into English, and test its psychometric properties among North-American spine trauma patients.

SUMMARY OF BACKGROUND DATA

In the absence of an outcome instrument specifically designed and validated for traumatic spinal column injury patients, it is difficult to measure the effect size of various treatment options. The AOSpine Knowledge Forum Trauma initiated a project and developed the AOSpine PROST consisting of 19 items.

METHODS

Patients were recruited from two level-1 North-American trauma centers. For concurrent validity, next to AOSpine PROST also 36-item Short-Form Health Survey (SF-36) was filled out by patients. Patient characteristics were analyzed using descriptive statistics. Floor and ceiling effects as well as the number of inapplicable and missing questions were analyzed for content validity. Cronbach α and item-total correlation coefficients (ITCCs) were calculated for internal consistency. Spearman correlation tests were performed within AOSpine PROST items and in correlation to SF-36. Test-retest reliability was assessed using intraclass correlation coefficients (ICCs). Factor analysis was performed to explore any dimensions within AOSpine PROST.

RESULTS

The AOSpine PROST was translated adapted into English using established guidelines. Of 196 enrolled patients, 162 (82.7%) met the inclusion criteria and provided sufficient data. Content validity showed good results, and no floor and ceiling effects were seen. The internal consistency was excellent (Cronbach α = 0.97; ITCC 0.50-0.90) as well as test-retest reliability (ICC = 0.97). Spearman correlations were good (0.29-0.85). The strongest correlations of AOSpine PROST with SF-36 were seen with the physical components (0.69-0.82; P < 0.001). Factor analysis revealed two possible dimensions (Eigen values >1), explaining 75.7% of variance.

CONCLUSION

The English version of AOSpine PROST showed very good validity and reliability. It is considered as a valuable tool, and has the potential to contribute to the reduction of ongoing controversies in spine trauma care.

LEVEL OF EVIDENCE

2.

Reliability, validity and responsiveness of the Dutch version of the AOSpine PROST (Patient Reported Outcome Spine Trauma)

PURPOSE

To validate the Dutch version of AOSpine PROST (Patient Reported Outcome Spine Trauma).

METHODS

Patients were recruited from two level-1 trauma centers from the Netherlands. Next to the AOSpine PROST, patients also filled out SF-36 for concurrent validity. Descriptive statistics were used to analyze the characteristics. Content validity was assessed by evaluating the number of inapplicable or missing questions. Also floor and ceiling effects were analyzed. Internal consistency was assessed by calculating Cronbach's α and item-total correlation coefficients (itcc). Spearman correlation tests were performed within AOSpine PROST items and in correlation with SF-36. Test-retest reliability was analyzed using Intraclass Correlation Coefficients (ICC). Responsiveness was assessed by calculating effect sizes (ES) and standardized response mean (SRM). Factor analysis was performed to explore any dimensions within AOSpine PROST.

RESULTS

Out of 179 enrolled patients, 163 (91.1%) were included. Good results were obtained for content validity. No floor or ceiling effects were seen. Internal consistency was excellent (Cronbach's α = 0.96, itcc 0.50-0.86), with also good Spearman correlations (0.25-0.79). Compared to SF-36, the strongest correlation was seen for physical functioning (0.79; p < .001). Also test-retest reliability was excellent (ICC = 0.92). Concerning responsiveness analysis, very good results were seen with ES = 1.81 and SRM = 2.03 (p < 0.001). Factor analysis revealed two possible dimensions (Eigenvalues > 1), explaining 65.4% of variance.

CONCLUSIONS

Very satisfactory results were obtained for reliability, validity and responsiveness of the Dutch version of AOSpine PROST. Treating surgeons are encouraged to use this novel and validated tool in clinical setting and research to contribute to evidence-based and patient-centered care.

Early versus delayed corpectomy in thoracic and lumbar spine trauma. A long-term clinical and radiological retrospective study

AND BACKGROUND DATA

Many authors have demonstrated the necessity of reconstruction of the anterior column in spinal trauma with vertebral body collapse or nonunion. There is no publication comparing the result depending on the time between trauma and anterior reconstruction of the vertebral body.

OBJECTIVE

To compare long-term clinical and radiological results between early and late anterior vertebral body reconstruction with expandable cages in patients with thoracic and lumbar spine trauma.

HYPOTHESIS

An early anterior reconstruction of thoracolumbar fractures provides better clinical and radiological outcomes than a delayed one.

MATERIALS AND METHODS

A retrospective clinical study was carried out with 44 consecutive patients with injuries of the thoracic and lumbar spine treated operatively with combined posterior stabilization and anterior reconstruction with an expandable implant for vertebral body replacement. All patients were evaluated with EOS full-spine radiograph and CT-scan. The mean follow-up was 5.1 years. Clinical result was evaluated with ODI, SF12, VAS back pain, return to work and sport. Radiological result was evaluated with regional kyphosis angle (RKA) evolution, fusion rate and sagittal alignment. In Group A, twenty-nine patients underwent an early anterior reconstruction within 3 weeks after trauma. The indication of vertebral body reconstruction was placed after post-operative CT-scan for a Mc Cormack score≥7. In Group B, fifteen patients underwent a late anterior reconstruction after diagnosis of nonunion by the combination of pain and CT-scan after 1 year.

RESULTS

Clinical scores and scales were significantly better for patients operated early in Group A. Return to work and activities were significantly more important in Group A too. The mean RKA correction with posterior reduction was 9.3°. The secondary anterior approach permit to reduce 2.9° more. At last follow-up, the loss of reduction was 4.3°. There was no significant difference between groups for those results. No difference in fusion rate was observed between groups. There was no significant difference between groups in the sagittal alignment excepted for SVA that was higher for Group B while remaining under a normal value of 50mm.

CONCLUSION

Early anterior vertebral body reconstruction for fractures gives better clinical results than delayed reconstruction for patients with diagnosis of nonunion in patients with thoracic and lumbar spine trauma. Moreover, the shorter the time from trauma to operation, the better the sagittal reduction of kyphosis. The use of expandable titanium cage is a good way to perform and maintain this reduction.

LEVEL OF EVIDENCE

IV, retrospective study.

Current status of short segment fixation in thoracolumbar spine injuries

Short segment fixation aims to restore spinal stability and alignment in thoracolumbar spine injuries while preserving spinal motion by decreasing the levels of spine involved in fixation. In its simplest form it applies to fixation one level above and one level below the fractured vertebra. It has proven effective with good clinical, functional and radiological results in well selected cases. However not insignificant rates of sagittal collapse and recurrence of kyphosis with or without clinical implications have also been reported. Most of the failures were attributed to lack of anterior column integrity and relatively inferior robustness of earlier posterior short segment constructs. With better understanding of fracture biomechanics, better implant designs and evolution of strategies to increase the biomechanical strengths of posterior constructs, the rates of kyphosis recurrence and implant failure have been significantly reduced. Although there is lack of robust evidence to guide a surgeon to the best approach for a particular fracture, adhering to basic biomechanical principals increases the efficacy and reliability of short segment fixation. This narrative review highlights the status of short segment fixation in dorsolumbar spine injuries with emphasis on patient selection and strategies to increase effectiveness and reduce failures of short segment fixation.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines on the Evaluation and Treatment of Patients with Thoracolumbar Spine Trauma: Surgical Approaches

QUESTION

Does the choice of surgical approach (anterior, posterior, or combined anterior-posterior) improve clinical outcomes in patients with thoracic and lumbar fractures?

RECOMMENDATIONS

In the surgical treatment of patients with thoracolumbar burst fractures, physicians may use an anterior, posterior, or a combined approach as the selection of approach does not appear to impact clinical or neurological outcomes. Strength of Recommendation: Grade B With regard to radiologic outcomes in the surgical treatment of patients with thoracolumbar fractures, physicians may utilize an anterior, posterior, or combined approach because there is conflicting evidence in the comparison among approaches. Strength of Recommendation: Grade Insufficient With regard to complications in the surgical treatment of patients with thoracolumbar fractures, physicians may use an anterior, posterior, or combined approach because there is conflicting evidence in the comparison among approaches. Strength of Recommendation: Grade Insufficient The full version of the guideline can be reviewed at: https://www.cns.org/guideline-chapters/congress-neurological-surgeons-systematic-review-evidence-based-guidelines/chapter_11.

Role of minimally invasive percutaneous fixation in thoracolumbar fractures: a prospective study

Background

Each year, there are approximately 5 million new vertebral fractures worldwide. Being a mobile flexible segment that is prone to severe stresses and loads, thoracolumbar fractures are considered one of the most controversial and challenging fracture types to manage.

Objective

The aim of this study is to explore the technique and to evaluate feasibility, safety, and outcome of percutaneous transpedicular fixation in the management of thoracolumbar fractures.

Methods

This study was carried out in the period between May 2016 and June 2017, where 20 consecutive patients with thoracolumbar fractures, based on TLICS scoring and neurological status, underwent a posterior percutaneous transpedicular fixation. The mean age was 33.85 years, range 20–49 years. Patients were followed up for 12 months. Patients had their clinical outcomes reviewed and evaluated in terms of cosmesis by visual analog scale (VAS) and in terms of Cobb angle correction.

Results

The length of the procedure varied from 120 to 180 min with mean time of 154.50 min. There was no significant blood loss in all cases. The volume of blood loss ranged from 150 to 200 cc with mean loss of 174.25 cc.

No major intraoperative complications happened in our study cases. Six cases had only one laterally malpositioned screw each. All cases returned to their previous activity without limitations (E5). Those who were completely pain free (F5) were 15 patients. Only five patients were suffering from moderate pain (F4). The Prolo scale was either 9 or 10 with mean of 9.60.

Conclusion

By comparing our results with other studies, we found more or less equivalence in terms of neurological recovery, functional outcome, fusion rate, and maintenance of correction gain. However, the cosmesis scores for patients in the study were great.

A comparative study between the Universal Spinal System® (USS) and the CD Horizon® Legacy™ (CDH) in the management of thoracolumbar fractures

Introduction: For the treatment of unstable non-osteoporotic thoracolumbar fractures, the clinical and radiological outcome of short-segment fixation with the USS™ – Universal Spine System (DePuy Orthopedics, Inc., Warsaw, IN, USA) and the CD HORIZON^® LEGACY™ 5.5 Spinal System, (Medtronic Sofamor Danek USA, Inc., Memphis, TN, USA) were compared.

Methods: From March 2015 to January 2016, 40 consecutive patients with unstable traumatic thoracolumbar fractures who met our inclusion criteria were treated with either the USS system or CDH Legacy system. Segmental kyphosis angle (SKA) and anterior body height (ABH) of fractured vertebrae, and ASIA Impairment Scale (AIS) were evaluated. Radiological fusion was confirmed with plain X-rays and when indicated with computerized tomography (CT).

Results: The mean immediate kyphotic angle correction was 16.6° for the Schanz and 6.4 for the Legacy system, and the immediate mean anterior vertebral body height correction was 0.92 cm for the Schanz and 0.51 cm for the Legacy system. Our study shows a significant statistical difference between Schanz and Legacy systems regarding post-operative segmental kyphosis and height correction immediately postoperatively, at 6 months and at one-year follow-up (p-value < 0.005). The degree of pain reduction and neurological improvement was not influenced by the screw system.

Conclusion: Usage of USS in thoracolumbar fracture as a short-segment fixation led to a near anatomical reduction when compared to the Legacy system. However, there was no advantage regarding pain reduction and neurological outcome.

Implants for Vertebral Body Replacement - Which Systems are Available and Have Become Established

Since the first vertebral body replacement operations over 50 years ago until now, there were developed numerous methods and implants. Vertebral body replacement after corpectomy nowadays is a standard procedure in spinal surgery. At the beginning mainly bone grafts were used. Due to continuous development, PMMA and titanium implants were developed. Nowadays various expandable and non-expandable implants are available. Numerous implants can still be justified. The question arises which methods and systems are on the market and which ones have proven themselves? This article describes and compares the advantages and disadvantages of each implant type.

Treatment of Fractures of the Thoracolumbar Spine: Recommendations of the Spine Section of the German Society for Orthopaedics and Trauma (DGOU)

STUDY DESIGN

consensus paper with systematic literature review.

OBJECTIVE

The aim of this study was to establish recommendations for treatment of thoracolumbar spine fractures based on systematic review of current literature and consensus of several spine surgery experts.

METHODS

The project was initiated in September 2008 and published in Germany in 2011. It was redone in 2017 based on systematic literature review, including new AOSpine classification. Members of the expert group were recruited from all over Germany working in hospitals of all levels of care. In total, the consensus process included 9 meetings and 20 hours of video conferences.

RESULTS

As regards existing studies with highest level of evidence, a clear recommendation regarding treatment (operative vs conservative) or regarding type of surgery (posterior vs anterior vs combined anterior-posterior) cannot be given. Treatment has to be indicated individually based on clinical presentation, general condition of the patient, and radiological parameters. The following specific parameters have to be regarded and are proposed as morphological modifiers in addition to AOSpine classification: sagittal and coronal alignment of spine, degree of vertebral body destruction, stenosis of spinal canal, and intervertebral disc lesion. Meanwhile, the recommendations are used as standard algorithm in many German spine clinics and trauma centers.

CONCLUSION

Clinical presentation and general condition of the patient are basic requirements for decision making. Additionally, treatment recommendations offer the physician a standardized, reproducible, and in Germany commonly accepted algorithm based on AOSpine classification and 4 morphological modifiers.

Radiologic and Functional Outcomes in Unstable Thoracolumbar Fractures Treated With Short-segment Pedicle Instrumentation

STUDY DESIGN

A retrospective review of radiographs, clinical charts, and health questionnaires of 40 patients.

OBJECTIVE

To evaluate the radiologic and functional results of unstable thoracolumbar fractures treated with short-segment pedicle instrumentation (SSPI).

A SUMMARY OF BACKGROUND DATA

Although earlier publications report a risk of correction loss or material failure after short-segment fixation in unstable thoracolumbar fractures, more current data suggest that improvements in this technique could offer good clinical and radiologic results.

MATERIALS AND METHODS

We undertook a retrospective review of 40 patients with unstable thoracolumbar fractures treated with SSPI. Radiographs and computed tomogrphic scans were analyzed to determine fracture classification and sagittal plane deformity, estimated by the Cobb method. The rates of final kyphosis and correction loss and their relationship with the Load Sharing Classification (LSC) and the AO classification were analyzed. We reviewed the hospital charts to identify complications and outcomes. At the final follow-up, the Short-Form 36 health survey was carried out to evaluate the functional outcome. The relationship between conditions such as polytrauma, neurological compromise or fracture site, and radiological and functional outcomes was also analyzed.

RESULTS

We observed mean values of 5.9 degrees of final follow-up kyphosis and 5.1 degrees of correction loss. One case of material failure was seen. The severity in the LSC or the AO classification, polytrauma, neurological compromise, or fracture site had no relationship with worse radiologic or functional outcomes.

CONCLUSIONS

SSPI shows good results in fracture reduction, with good functional outcomes despite the loss of correction seen at the final follow-up. Although no investigated variable was found to be predictive of radiographic failure, a trend was identified (P=0.07) that patients with a higher LSC had an increased loss of correction.

Combined anteroposterior fixation using a titanium cage versus solely posterior fixation for traumatic thoracolumbar fractures: A systematic review and meta-analysis

Study Design:

Systematic review with meta-analysis.

Objective:

Additional anterior stabilization might prevent posterior implant failure, but over time, the disadvantageous of bone grafts have become evident. The objective of this systematic review was to compare risks and advantages of additional anterior stabilization with a titanium cage to solely posterior fixation for traumatic thoracolumbar fractures.

Methods:

An electronic search was performed in the literature from 1980 to March 2016. Studies comparing only posterior with anteroposterior fixation by means of a titanium cage were included in this study. Data extraction and Cochrane risk of bias assessment were done by two independent authors. In addition, the PRISMA statement was followed, and the GRADE approach was used to present results.

Results:

Of the 1584 studies, two randomized controlled trials (RCTs) and one retrospective cohort study were included in the meta-analysis. The RCTs reported evidence of high quality that anteroposterior stabilization maintained better kyphosis correction than posterior stabilization alone. However, these results were neutralized in the meta-analysis by the cohort study. Implant failure was reported by one study, in the posterior group. No differences in follow-up visual analog scale scores, neurologic improvement, and complications were found. Operation time, blood loss, and hospital stay all increased in the anteroposterior group.

Conclusions:

Patients with a highly comminuted or unstable fracture could benefit from combined anteroposterior stabilization with a titanium cage, for some evidence suggests this prevents loss of correction. However, large randomized studies still lack. There is a risk of cage subsidence, and increased perioperative risks have to be considered when choosing the optimal treatment.

Is additional balloon Kyphoplasty safe and effective for acute thoracolumbar burst fracture?

BACKGROUND

Burst fracture is a common thoracolumbar injury that is treated using posterior pedicle instrumentation and fusion combined with transpedicular intracorporeal grafting after reduction. In this study, we compared the outcome of these two techniques by using radiologic imaging and functional outcome.

METHODS

Sixty-one patients with acute thoracolumbar burst fracture were operated with kyphoplasty (n = 31) or vertebroplasty (n = 30) and retrospectively reviewed in our institution between 2011 and 2014. All 61 patients underwent surgery within 5 days after admission to the hospital and then followed-up for 12 to 24 months after surgery.

RESULTS

Significant improvement was found in the anterior vertebral height (92 ± 8.9% in the kyphoplasty group, 85.6 ± 7.2% in the vertebroplasty group, p < 0.01) at 1 month post-operatively and (89 ± 7.9% in the kyphoplasty group, 78 ± 6.9% in the vertebroplasty group, p < 0.01) at the 24-month follow-up. Significant improvement was also observed in the kyphotic angle (1.2 ± 0.5° in the kyphoplasty group, 10.5 ± 1.2° in the vertebroplasty group, p < 0.01) at 1 month post-operatively and (5.4 ± 1.2° in the kyphoplasty group, 11.5 ± 8.5° in the vertebroplasty group, p < 0.01) at the 24-month follow-up. Both operations led to significant improvement of the patients' pain and the Oswestry disability index (p < 0.01). Cement leakage was noted in 29% of patients after kyphoplasty and 77% of patients after vertebroplasty (p < 0.01). Only one implant failure (3.3%), which required further surgical intervention, was reported in the vertebroplasty group.

CONCLUSIONS

Reduction with additional balloon at the fractured site is better than indirect reduction only by posterior instrumentation. The better reduction of kyphotic angle and the lower cement leakage rate in the kyphoplasty group indicate that additional balloon kyphoplasty is safe and effective for acute thoracolumbar burst fracture.

Cost-Utility Analysis of Pedicle Screw Removal After Successful Posterior Instrumented Fusion in Thoracolumbar Burst Fractures

STUDY DESIGN

A cost-utility analysis (CUA).

OBJECTIVE

The aim of this study was to determine the cost-effectiveness of pedicle screw removal after posterior fusion in thoracolumbar burst fractures.

SUMMARY OF BACKGROUND DATA

Pedicle screw instrumentation is a standard fixation method for unstable thoracolumbar burst fracture. However, removal of the pedicle screw after successful fusion remains controversial because the clinical benefits remain unclear. CUA can help clinicians make appropriate decisions about optimal health care for pedicle screw removal after successful fusion in thoracolumbar burst fractures.

METHODS

We conducted a single-center, retrospective, longitudinal matched-cohort study of prospectively collected outcomes. In total, 88 consecutive patients who had undergone pedicle screw instrumentation for thoracolumbar burst fracture with successful fusion confirmed by computed tomography (CT) were used in this study. In total, 45 patients wanted to undergo implant removal surgery (R group), and 43 decided not to remove the implant (NR group). A CUA was conducted from the health care perspective. The direct costs of health care were obtained from the medical bill of each patient. Changes in health-related quality of life (HRQoL) scores, validated by Short Form 6D, were used to calculate quality-adjusted life-years (QALYs). Total costs and gained QALY were calculated at 1 year (1 year) and 2 years (2 years) compared with baseline. Results are expressed as an incremental cost-effectiveness ratio (ICER). Different discount rates (0%, 3%, and 5%) were applied to both cost and QALY for sensitivity analysis.

RESULTS

Baseline patient variables were similar between the two groups (all P > 0.05). The additional benefits of implant removal (0.201 QALY at 2 years) were achieved with additional costs ($2541 at 2 years), equating to an ICER of $12,641/QALY. On the basis of the different discount rates, the robustness of our study's results was also determined.

CONCLUSION

Implant removal after successful fusion in a thoracolumbar burst fracture is cost-effective until postoperative year 2.

LEVEL OF EVIDENCE

3.

Temporary short-segment pedicle screw fixation for thoracolumbar burst fractures: comparative study with or without vertebroplasty

BACKGROUND CONTEXT

Short-segment posterior spinal instrumentation for thoracolumbar burst fracture provides superior correction of kyphosis by an indirect reduction technique, but it has a high failure rate.

PURPOSE

The purpose of the study we report here was to compare outcomes for temporary short-segment pedicle screw fixation with vertebroplasty and for such fixation without vertebroplasty.

STUDY DESIGN

This is a prospective multicenter comparative study.

PATIENT SAMPLE

We studied 62 consecutive patients with thoracolumbar burst fracture who underwent short-segment posterior instrumentation using ligamentotaxis with Schanz screws with or without vertebroplasty.

OUTCOME MEASURES

Radiological parameters (Cobb angle on standing lateral radiographs) were used.

METHODS

Implants were removed approximately 1 year after surgery. Neurologic function, kyphotic deformity, canal compromise, and fracture severity were evaluated prospectively.

RESULTS

After surgery, all patients with neurologic deficit had improvement equivalent to at least one grade on the American Spinal Injury Association impairment scale and had fracture union. Kyphotic deformity was reduced significantly, and reduction of the vertebrae was maintained with and without vertebroplasty, regardless of load-sharing classification. Although no patient required additional anterior reconstruction, kyphotic change was observed at disc level mainly after implant removal with or without vertebroplasty.

CONCLUSIONS

Temporary short-segment fixation yielded satisfactory results in the reduction and maintenance of fractured vertebrae with or without vertebroplasty. Kyphosis recurrence may be inevitable because adjacent discs can be injured during the original trauma.

The Safety and Strength of a Novel Medial, Partial Nonthreaded Pedicle Screw: A Cadaveric and Biomechanical Investigation

STUDY DESIGN

Cadaveric and biomechanical study.

OBJECTIVE

The aim of this study was to assess the safety and pullout strength of medial, partial nonthreaded thoracic pedicle screws compared with conventional screws.

SUMMARY OF BACKGROUND DATA

The perforation rate of the pedicle screws has been reported as high as 41%. Nerve injury and irritation can result from the compression of malpositioned screw on neural structures.

METHODS

Ten fresh cadavers were studied. Screws, 5.0 and 6.0 mm, were inserted from T1 to T6 and T7 to T12, respectively. Pedicle perforations and fractures were recorded upon screw insertion and final positioning (nonthreaded portion facing medially) after a wide laminectomy. Pullout strength of novel and conventional screws were then tested using an Instron machine in an artificial bone substitute.

RESULTS

A total of 240 thoracic pedicle screws were inserted. Of them, 88.8% (213 screws) were fully contained during screw insertion. There were 5.0% (12 screws) grade 1 medial perforations and 6.2% (15 screws) grade 1 lateral perforations during screw insertion. Upon final positioning, 93.8% (225 screws) were fully contained. All grade 1 medial perforations, which occurred during insertion, were converted to grade 0. No dural or nerve root injuries occurred. Pedicle split fractures were noted in 6.7% (16 screws). The use of medial, partial nonthreaded screws reduced the overall perforation rate from 11.2% to 6.2%. The mean pullout load for the 5 mm fully threaded screw versus medial, partial nonthreaded was 1419.3±106.1 N (1275.8-1538.8 N) and 1336.6±44.2 N (1293.0-1405.1 N) respectively, whereas 6 mm pullout load averaged 2126.0±134.8 N (1986.3-2338.3 N) and 2036.5±210.0 N (1818.4-2355.9 N). The difference was not statistically significant.

CONCLUSIONS

The use of medial, partial nonthreaded pedicle screws reduced the medial perforation rate from 5.0% to 0%; however, the pullout strength was not significantly reduced. The use of this novel screw can potentially reduce the incidence of nerve injury or irritation after medial pedicle perforations.

Single-stage Transpedicular Vertebrectomy and Expandable Cage Placement for Treatment of Unstable Mid and Lower Lumbar Burst Fractures

STUDY DESIGN

Retrospective clinical and radiographic study.

OBJECTIVE

To examine the efficacy and safety of vertebrectomy and expandable cage placement by a single-stage posterior approach for unstable mid and lower lumbar burst fractures (below the L3).

SUMMARY OF BACKGROUND DATA

Patients with unstable mid and lower lumbar burst fractures require surgical treatment to relieve pain, address paralysis, and stabilize the spine to prevent further segmental deformity. However, controversy remains regarding the optimal surgical treatment.

MATERIALS AND METHODS

Eleven patients underwent single-stage posterior-only vertebral column resection and vertebral body reconstruction using an expandable cage. Neurological status was classified using the American Spinal Injury Association (ASIA) Impairment Scale, whereas functional outcome was analyzed using a visual analog scale for back pain. Segmental Cobb angles were measured above and below the fractured vertebral body preoperatively, immediate postoperatively, and at the last follow-up.

RESULTS

The preoperative neurological status was ASIA grade E in 2 patients, grade D in 5 patients, grade C in 2 patients, and grade B in 2 patients. Postoperatively, neurological stability was demonstrated in 3 patients (27%), and 8 (73%) showed improvement in the ASIA grade. The mean preoperative visual analog scale score was 8.3, which decreased to 4.5 postoperatively, and to 1.8 at the final follow-up. The mean preoperative segmental lordotic angle was 9.2 degrees, which increased to 16.9 degrees postoperatively, and decreased to 15.1 degrees at the last follow-up. The mean operating time was 208.8 minutes, and the mean blood loss was 1006.3 mL. Regarding surgical complications, 1 patient experienced a dural tear and 1 patient demonstrated cage subsidence.

CONCLUSIONS

The results of this small series suggest the feasibility, efficacy, and safety of this surgical option for unstable mid and lower lumbar burst fractures. This technique from a single posterior approach offers several advantages over traditional anterior or combined approaches using strut graft or nonexpandable implants.

Biomechanical comparison of short-segment posterior fixation including the fractured level and circumferential fixation for unstable burst fractures of the lumbar spine in a calf spine model

OBJECTIVE There has been a transition from long- to short-segment instrumentation for unstable burst fractures to preserve motion segments. Circumferential fixation allows a stable short-segment construct, but the associated morbidity and complications are high. Posterior short-segment fixation spanning one level above and below the fractured vertebra has led to clinical failures. Augmentation of this method by including the fractured level in the posterior instrumentation has given promising clinical results. The purpose of this study is to compare the biomechanical stability of short-segment posterior fixation including the fractured level (SSPI) to circumferential fixation in thoracolumbar burst fractures. METHODS An unstable burst fracture was created in 10 fresh-frozen bovine thoracolumbar spine specimens, which were grouped into a Group A and a Group B. Group A specimens were instrumented with SSPI and Group B with circumferential fixation. Biomechanical characteristics including range of motion (ROM) and load-displacement curves were recorded for the intact and instrumented specimens using Universal Testing Device and stereophotogrammetry. RESULTS In Group A, ROM in flexion, extension, lateral flexion, and axial rotation was reduced by 46.9%, 52%, 49.3%, and 45.5%, respectively, compared with 58.1%, 46.5%, 66.6%, and 32.6% in Group B. Stiffness of the construct was increased by 77.8%, 59.8%, 67.8%, and 258.9% in flexion, extension, lateral flexion, and axial rotation, respectively, in Group A compared with 80.6%, 56.1%, 82.6%, and 121.2% in Group B; no statistical difference between the two groups was observed. CONCLUSIONS SSPI has comparable stiffness to that of circumferential fixation.

Comparison of Surgical Outcomes Between Short-Segment Open and Percutaneous Pedicle Screw Fixation Techniques for Thoracolumbar Fractures

Background

This study aimed to compare the surgical outcomes between open pedicle screw fixation (OPSF) and percutaneous pedicle screw fixation (PPSF) for the treatment of thoracolumbar fractures, which has received scant research attention to date.

Material/Methods

Eight-four patients with acute and subacute thoracolumbar fractures who were treated with SSPSF from January 2013 to June 2014 at the Changzhou Hospital of Traditional Chinese Medicine (Changzhou, China) were retrospectively reviewed. The patients were divided into 4 groups: the OPSF with 4 basic screws (OPSF-4) group, the OPSF with 4 basic and 2 additional screws (OPSF-6) group, the PPSF with 4 basic screws (PPSF-4) group, and the PPSF with 4 basic and 2 additional screws (PPSF-6) group. The intraoperative, immediate postoperative, and over 1-year follow-up outcomes were evaluated and compared among these groups.

Results

Blood loss in the PPSF-4 group and the PPSF-6 group was significantly less than in the OPSF-4 group and the OPSF-6 group (P<0.05). The OPSF-6 group exhibited significantly higher immediate postoperative correction percentage of anterior column height of fractured vertebra than the other 3 groups (P<0.05), and higher correction of sagittal regional Cobb angle and kyphotic angle of injured vertebra than in the PPSF-4 and -6 groups (P<0.05). In addition, there was no significant difference in the correction loss of percentage of anterior column height, and loss of sagittal Cobb angle and kyphotic angle of fractured vertebrae at final follow-up among the 4 groups (P>0.05).

Conclusions

OPSF with 6 screws had an advantage in the correction of injured vertebral height and kyphosis, and PPSF reduced the intraoperative blood loss of patients.

Short Segment Spinal Instrumentation With Index Vertebra Pedicle Screw Placement for Pathologies Involving the Anterior and Middle Vertebral Column Is as Effective as Long Segment Stabilization With Cage Reconstruction: A Biomechanical Study

STUDY DESIGN

An in vitro, cadaveric biomechanical study.

OBJECTIVE

The aim of the present study was to compare single-segment posterior instrumentation and fracture-level screws with single/multilevel posterior fixation and corpectomy in a simulated, unstable burst fracture model.

SUMMARY OF BACKGROUND DATA

The optimal extent of instrumentation for surgical cases of non-neoplastic vertebral body pathologies remains uncertain. Although several clinical studies demonstrate advantages of short segment instrumentation with index-level screws over more extensive corpectomy and anterior-posterior techniques, a comprehensive biomechanical comparison of these techniques is currently lacking.

METHODS

Six bovine spines (T11-L5) were tested in flexion, extension, lateral bending (LB), and axial rotation (AR) following simulated burst fracture at L2. Posterior instrumentation included 1 level above/below (1LF) and 2 levels above/below fracture level (2LF), intermediate or index screws at fracture level (FF), and cross-connectors above/below fracture level (CC). Anterior corpectomy devices included expandable corpectomy spacers with/without integrated screws, ACDi and ACD, respectively FORTIFY-Integrated/FORTIFY; Globus Medical, Inc., PA. Constructs were tested in the following order: (1) Intact; (2) 1LF; (3) 1LF and CC; (4) 1LF and FF; (5) 1LF, CC, and FF; (6) 2LF; (7) 2LF and CC; (8) 2LF and FF; (9) 2LF, CC, and FF; (10) 2LF and ACD; (11) 2LF, ACD, and CC; (12) 1LF and ACDi; (13) 1LF, ACDi, and CC.

RESULTS

During flexion, all constructs except 1LF reduced motion relative to intact (P ≤ 0.05). Anterior support was most stable, but no differences were found between constructs (P ≥ 0.05). Every construct reduced motion in extension, though no differences were found between constructs and intact (P ≥ 0.05). During LB, all constructs reduced motion relative to intact (P ≤ 0.05); 2LF constructs further reduced motion (P ≤ 0.05). No construct returned AR motion to intact, with significant increases in 1LF and ACDi, 2LF and ACD, and 2LF, ACD, and CC (P ≤ 0.05). Cross-connectors and fracture screws reinforced each other in posterior-only constructs, providing maximum stability (P ≥ 0.05).

CONCLUSIONS

This biomechanical comparison study found no significant superiority of combined anterior-posterior constructs over short segment fracture screw fixation, only multilevel posterior instrumentation with and without anterior support, providing increased stability in LB. Biomechanical equivalency suggests that short segment fracture screw intervention may provide appropriate stabilization for non-neoplastic pathologies involving the anterior and middle vertebral columns.

LEVEL OF EVIDENCE

2.

Comparison between percutaneous fluoroscopic-guided and conventional open pedicle screw placement techniques for the thoracic spine

Percutaneous placement of pedicle screws is a well-established technique, however, no studies have compared percutaneous and open placement of screws in the thoracic spine. The aim of this cadaveric study was to compare the accuracy and safety of these techniques at the thoracic spinal level. A total of 288 screws were inserted in 16 (eight cadavers, 144 screws in percutaneous and eight cadavers, 144 screws in open). Pedicle perforations and fractures were documented subsequent to wide laminectomy followed by skeletalisation of the vertebrae. The perforations were classified as grade 0: no perforation, grade 1: < 2 mm perforation, grade 2: 2 mm to 4 mm perforation and grade 3: > 4 mm perforation. In the percutaneous group, the perforation rate was 11.1% with 15 (10.4%) grade 1 and one (0.7%) grade 2 perforations. In the open group, the perforation rate was 8.3% (12 screws) and all were grade 1. This difference was not significant (p = 0.45). There were 19 (13.2%) pedicle fractures in the percutaneous group and 21 (14.6%) in the open group (p = 0.73). In summary, the safety of percutaneous fluoroscopy-guided pedicle screw placement in the thoracic spine between T4 and T12 is similar to that of the conventional open technique.

Cite this article: Bone Joint J 2015;97-B:1555–61.

The benefits of elective spinal implant removal: a retrospective study of 137 patients

PURPOSE

While spinal instrumentations are becoming more common, the advantages of elective spinal implant removal remain ambiguous. We hypothesized that elective implant removal of the posterior spine is beneficial.

METHODS

A retrospective study evaluated 137 consecutive trauma patients with elective implant removal of the posterior spine. If additional cages were present, they were not removed. Primary outcomes were the change in pre- and post-operative pain, fingertip-floor distance (FFD), and Cobb angles. Some secondary outcomes consisted of complications, work disability, and pelvic incidence (PI). Different stabilization approaches and cage sizes were compared.

RESULTS

The presence and amount of pain as well as the FFD showed significant improvement. There was no loss of reduction. Delayed wound healing was observed in 9%, but only 3% needed revision. Thoracic fascial dehiscences were seen only in patients (9%) that had stand-alone posterior surgery. Larger cages were associated with increased work disability. An increased PI was associated with less post-operative pain and decreased FFD.

CONCLUSIONS

In this study, trauma patients benefited from elective implant removal of the posterior spine due to lower presence and level of pain, improved function and low revision rates; irrespective of an initial combined or stand-alone posterior approach or varying cage sizes. However, stand-alone posterior instrumentation may be accompanied by increased rates of fascial dehiscence surgeries and larger cages may lead to increased work disability. Increased PI may be associated with less pain after spinal implant removal.

Viability and long-term survival of short-segment posterior fixation in thoracolumbar burst fractures

BACKGROUND CONTEXT

Short-segment pedicle screw instrumentation constructs for the treatment of thoracolumbar fractures gained popularity in the 1980s. The load-sharing classification (LSC) is a straightforward way to describe the extent of bony comminution, amount of fracture displacement, and amount of correction of kyphotic deformity in a spinal fracture. There are no studies evaluating the relevance of fracture comminution/traumatic kyphosis on the long-term radiologic outcome of burst fractures treated by short-segment instrumentation with screw insertion in the fractured level.

PURPOSE

To evaluate the efficacy of the six-screw construct in the treatment of thoracolumbar junction burst fractures and the influence of the LSC score on the 2-year radiologic outcome.

STUDY DESIGN

Case series of consecutive patients of a single university hospital.

PATIENT SAMPLE

Consecutive patients from one university hospital with nonosteoporotic thoracolumbar burst fractures.

OUTCOME MEASURES

Being a radiology-based study, the outcome measures are radiologic parameters (regional kyphosis [RK], local kyphosis, and thoracolumbar kyphosis [TLK]) that evaluate the degree and loss of correction.

METHODS

Retrospective analysis of all consecutive patients with nonosteoporotic thoracolumbar burst fractures managed with a six-screw construct in a single university hospital, with more than 2 years' postoperative follow-up.

RESULTS

Eighty-six patients met the inclusion criteria, and 72 (83.7%) with available data were ultimately included in the study. The sample included 53 men and 19 women, with a mean (standard deviation [SD]) age of 35.6 years (14.4 years) at the time of surgery. Mean LSC score was 6.3 (SD 1.6, range 3-9). Forty-four of 62 (70.9) fractures had a score greater than 6. Mean (SD) RK and TLK deteriorated significantly during the first 6 months of follow-up: 2.90° (4.54°) p=.005 and 2.78° (6.45°) p=.069, respectively. Surgical correction correlated significantly (r=0.521, p<.0001) with the time elapsed until surgery. Loss of surgical correction (postoperative to 6-month RK and TLK increase) correlated significantly with the LSC score (r=0.57, p=.004; r=0.51, p=.022, respectively). Further surgery because of correction loss was not required in any case.

CONCLUSIONS

The six-screw construct is effective for treating thoracolumbar junction burst fractures. The medium-to-long-term loss of correction is affected by the amount of bony comminution of the fracture, objectified through the LSC score.

Percutaneous Dorsal Instrumentation of Vertebral Burst Fractures: Value of Additional Percutaneous Intravertebral Reposition-Cadaver Study

Purpose. The treatment of vertebral burst fractures is still controversial. The aim of the study is to evaluate the purpose of additional percutaneous intravertebral reduction when combined with dorsal instrumentation. Methods. In this biomechanical cadaver study twenty-eight spine segments (T11-L3) were used (male donors, mean age 64.9 ± 6.5 years). Burst fractures of L1 were generated using a standardised protocol. After fracture all spines were allocated to four similar groups and randomised according to surgical techniques (posterior instrumentation; posterior instrumentation + intravertebral reduction device + cement augmentation; posterior instrumentation + intravertebral reduction device without cement; and intravertebral reduction device + cement augmentation). After treatment, 100000 cycles (100–600 N, 3 Hz) were applied using a servohydraulic loading frame. Results. Overall anatomical restoration was better in all groups where the intravertebral reduction device was used (p < 0.05). In particular, it was possible to restore central endplates (p > 0.05). All techniques decreased narrowing of the spinal canal. After loading, clearance could be maintained in all groups fitted with the intravertebral reduction device. Narrowing increased in the group treated with dorsal instrumentation. Conclusions. For height and anatomical restoration, the combination of an intravertebral reduction device with dorsal instrumentation showed significantly better results than sole dorsal instrumentation.

Minimally invasive spine surgery in the treatment of thoracolumbar and lumbar spine trauma

Thoracolumbar and lumbar trauma account for the majority of traumatic spinal injuries. The mainstay of current treatments is still nonoperative therapy with bracing. Classic treatment algorithms reserved absolute surgical intervention for spinal trauma patients with neurological compromise or instability. Relative indications included incapacitating pain and obesity/body habitus making brace therapy ineffective. In the past decade, minimally invasive surgical (MIS) techniques for spine surgery have been increasingly used for degenerative conditions. These same minimally invasive techniques have seen increased use in trauma patients. The goal of minimally invasive surgery is to decrease surgical morbidity through decreased soft-tissue dissection while providing the same structural stability afforded by classic open techniques. These minimally invasive techniques involve percutaneous posterior pedicle fixation, vertebral body augmentation, and utilization of endoscopic and thoracoscopic techniques. While MIS techniques are somewhat in their infancy, an increasing number of studies are reporting good clinical and radiographic outcomes with these MIS techniques. However, the literature is still lacking high-quality evidence comparing these newer techniques to classic open treatments. This article reviews the relevant literature regarding minimally invasive spine surgery in the treatment of thoracolumbar and lumbar trauma.

Cement augmentation in vertebral burst fractures

As a result of axial compression, traumatic vertebral burst fractures disrupt the anterior column, leading to segmental instability and cord compression. In situations with diminished anterior column support, pedicle screw fixation alone may lead to delayed kyphosis, nonunion, and hardware failure. Vertebroplasty and kyphoplasty (balloon-assisted vertebroplasty) have been used in an effort to provide anterior column support in traumatic burst fractures. Cited advantages are providing immediate stability, improving pain, and reducing hardware malfunction. When used in isolation or in combination with posterior instrumentation, these techniques theoretically allow for improved fracture reduction and maintenance of spinal alignment while avoiding the complications and morbidity of anterior approaches. Complications associated with cement use (leakage, systemic effects) are similar to those seen in the treatment of osteoporotic compression fractures; however, extreme caution must be used in fractures with a disrupted posterior wall.

Evidence-Based Medicine of Traumatic Thoracolumbar Burst Fractures: A Systematic Review of Operative Management across 20 Years

Study Design Systematic literature review. Objective The management of traumatic thoracolumbar burst fractures (TLBF) remains challenging, and analyzing the levels of evidence (LOEs) for treatment practices can reform the decision-making process. However, no review has yet evaluated the operative management of traumatic thoracolumbar burst fractures with particular attention placed on LOE from an established methodology. The objective of the present study was to characterize the literature evidence for TLBF, specifically for operative management. Methods A comprehensive search of the English literature over the past 20 years was conducted using PubMed (MEDLINE). The inclusion criteria consisted of (1) traumatic burst fractures (2) in the thoracic or lumbar spine. Exclusion criteria included (1) osteoporotic burst fractures, (2) pathologic burst fractures, (3) cervical fractures, (4) biomechanical studies or those involving cadavers, and (5) computer-based studies. Studies were assigned an LOE and those meeting level 1 or 2 were included. Results From 1,138 abstracts, 272 studies met the criteria. Twenty-three studies (8.5%) met level 1 (n = 4, 1.5%) or 2 (n = 19, 7.0%) criteria. All 23 studies were reported. Conclusions The literature contains a high LOE to support the operative management of traumatic thoracolumbar burst fractures. For patients who are neurologically intact, a high LOE demonstrated similar functional outcomes, lower complication rates, and less costs with conservative management when compared with surgical management. There is a high LOE for short- or long-segment pedicle instrumentation without fusion and less invasive (percutaneous and paraspinal) approaches. Furthermore, the posterior approaches are associated with lower complications as opposed to the anterior or combined approaches.

Anterior D-rod and titanium mesh fixation for acute mid-lumbar burst fracture with incomplete neurologic deficits: A prospective study of 56 consecutive patients

BACKGROUND

Anterior decompression and reconstruction have gained wide acceptance as viable alternatives for unstable mid-lumbar burst fracture, but there are no mid and long term prospective studies regarding clinical and radiologic results of mid-lumbar burst fractures.

MATERIALS AND METHODS

An Institutional Review Board-approved prospective study of 56 consecutive patients of mid-lumbar burst fractures with a load-sharing score of 7 or more treated with anterior plating was carried out. All patients were evaluated for radiologic and clinical outcomes. The fusion status, spinal canal compromise, segmental kyphotic angle (SKA), vertebral body height loss (VBHL), and adjacent segment degeneration was examined for radiologic outcome, whereas the American Spinal Injury Association scale, the visual analog scale (VAS), and the employment status were used for clinical evaluation.

RESULTS

The patients underwent clinical and radiologic followup for at least 5 years after the surgery. At the last followup, there was no case of internal fixation failure, adjacent segment degeneration, and other complications. Interbody fusion was achieved in all cases. The average fusion time was 4.5 months. No patient suffered neurological deterioration and the average neurologic recovery was 1.3 grades on final observation. Based on VAS pain scores, canal compromise, percentage of VBHL and SKA, the difference was statistically significant between the preoperative period and postoperative or final followup (P < 0.05). Results at postoperative and final followup were better than the preoperative period. However, the difference was not significant between postoperative and final followup (P > 0.05). Thirty-four patients who were employed before the injury returned to work after the operation, 15 had changed to less strenuous work.

CONCLUSION

Good mid term clinicoradiological results of anterior decompression with D-rod and titanium mesh fixation for suitable patients with mid-lumbar burst fractures with incomplete neurologic deficits can be achieved. The incident rate of complications was low. D-rod is a reliable implant and has some potential advantages in L4 vertebral fractures.

Comparison of two-stage open versus percutaneous pedicle screw fixation in treating pyogenic spondylodiscitis

Background

Percutaneous pedicle screw instrumentation is a minimally invasive surgical technique; however, the effects of using percutaneous pedicle screw fixation in treating patients with spinal infections have not yet been well demonstrated. The aim of this study, therefore, was to determine whether percutaneous posterior pedicle screw instrumentation is superior to the traditional open approach in treating pyogenic spondylodiscitis.

Methods

We retrospectively reviewed data for 45 patients treated for pyogenic spondylodiscitis with anterior debridement and interbody fusion followed by a second-stage procedure involving either traditional open posterior pedicle screw fixation or percutaneous posterior pedicle screw fixation. Twenty patients underwent percutaneous fixation and 25 patients underwent open fixation. Demographic, operative, and perioperative data were collected and analyzed.

Results

The average operative time for the percutaneous procedure was 102.5 minutes, while the average time for the open procedure was 129 minutes. The average blood loss for the percutaneous patients was 89 ml versus a 344.8 ml average for the patients in the open group. Patients who underwent the minimally invasive surgery had lower visual analogue scale scores and required significantly less analgesia afterwards. After two years of follow-up, neither recurrent infection nor intraoperative complications, such as wound infection or screw loosening, were found in the percutaneous group. Moreover, there was no significant difference in outcome between the two groups in terms of Oswestry Disability Index scores.

Conclusions

Anterior debridement and interbody fusion with bone grafting followed by minimally invasive percutaneous posterior instrumentation is an alternative treatment for pyogenic spondylodiscitis which can result in less intraoperative blood loss, shorter operative time, and reduced postoperative pain with no adverse effect on infection control.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2474-15-443) contains supplementary material, which is available to authorized users.