Rigid spine injuries - A comprehensive review on diagnostic and therapeutic challenges.

Injuries to the rigid spine have a distinguished position in the broad spectrum of spinal injuries due to altered biomechanical properties. The rigid spine is more prone to fractures. Two ossification bone disorders that are of particular interest are Ankylosing Spondylitis (AS) and Diffuse Idiopathic Skeletal Hyperostosis (DISH). DISH is a non-inflammatory condition that leads to an anterolateral ossification of the spine. AS on the other hand is a chronic inflammatory disease that leads to cortical bone erosions and spinal ossifications. Both diseases gradually induce stiffening of the spine. The prevalence of DISH is age-related and is therefore higher in the older population. Although the prevalence of AS is not age-related the occurrence of spinal ossification is higher with increasing age. This association with age and the aging demographics in industrialized nations illustrate the need for medical professionals to be adequately informed and prepared. The aim of this narrating review is to give an overview on the diagnostic and therapeutic measures of the ankylosed spine. Because of highly unstable fracture configurations, injuries to the rigid spine are highly susceptible to neurological deficits. Diagnosing a fracture of the ankylosed spine on plain radiographs can be challenging. Moreover, since 8% of patients with ankylosing spine disorders (ASD) have multiple non-contagious fractures, a CT scan of the entire spine is highly recommended as the primary diagnostic tool. There are no consensus-based guidelines for the treatment of spinal fractures in ASD. The presence of neurological deficit or unstable fractures are absolute indications for surgical intervention. If conservative therapy is chosen, patients should be monitored closely to ensure that secondary neurologic deterioration does not occur. For the fractures that have to be treated surgically, stabilization of at least three segments above and below the fracture zone is recommended. These fractures mostly are treated via the posterior approach. Patients with AS or DISH share a significant risk for complications after a traumatic spine injury. The most frequent complications for patients with thoracolumbar burst fractures are respiratory failure, pseudoarthrosis, pneumonia, and implant failure.

What Factors Influence Surgeons in Decision-Making in Thoracolumbar Burst Fractures? A Survey-Based Investigation of a Panel of Spine Surgery Experts.

STUDY DESIGN: Cross-sectional survey study. OBJECTIVE: To investigate factors affecting decision-making in thoracolumbar burst-fractures without neurologic deficit. METHODS: A 40-question survey addressing expert-related, economic, and radiological factors was distributed to 30 international trauma experts. Descriptive statistics were used to assess the impact of these factors on operative or non-operative management preferences. RESULTS: Out of 30 experts, 27 completed the survey. The majority of respondents worked at level 1 trauma centers (81.5%) within university settings (77.8%). They were primarily orthopedic surgeons (66.7%) and had over 10 years of experience (70.4%). About 81% found distinguishing between A3 and A4 fractures relevant for decision-making. Most experts (59%) treated A3 fractures non-surgically, while only 30% treated A4 fractures conservatively. Compensation systems did not influence treatment recommendations, and hospital measures promoting surgeries did not significantly affect distribution. Radiological factors, such as local kyphosis (25/27), fracture comminution (23/27), overall sagittal balance (21/27), and spinal canal narrowing (20/27), influenced decisions. CONCLUSION: Incomplete burst fractures (A3) are predominantly treated non-surgically, while complete burst fractures (A4) are primarily treated surgically. Compensation, third-party incentives, and outpatient care did not significantly impact decision-making. Radiological factors beyond the AO Spine thoracolumbar classification system seem to be essential and warrant further evaluation.

The Diagnostic Process of Spinal Post-traumatic Deformity: An Expert Survey of 7 Cases, Consensus on Clinical Relevance Does Exist.

STUDY DESIGN: Survey of cases. OBJECTIVE: To evaluate the opinion of experts in the diagnostic process of clinically relevant Spinal Post-traumatic Deformity (SPTD). SUMMARY OF BACKGROUND DATA: SPTD is a potential complication of spine trauma that can cause decreased function and quality of life impairment. The question of when SPTD becomes clinically relevant is yet to be resolved. METHODS: The survey of 7 cases was sent to 31 experts. The case presentation was medical history, diagnostic assessment, evaluation of diagnostic assessment, diagnosis, and treatment options. Means, ranges, percentages of participants, and descriptive statistics were calculated. RESULTS: Seventeen spinal surgeons reviewed the presented cases. The items' fracture type and complaints were rated by the participants as more important, but no agreement existed on the items of medical history. In patients with possible SPTD in the cervical spine (C) area, participants requested a conventional radiograph (CR) (76%-83%), a flexion/extension CR (61%-71%), a computed tomography (CT)-scan (76%-89%), and a magnetic resonance (MR)-scan (89%-94%). In thoracolumbar spine (ThL) cases, full spine CR (89%-100%), CT scan (72%-94%), and MR scan (65%-94%) were requested most often. There was a consensus on 5 out of 7 cases with clinically relevant SPTD (82%-100%). When consensus existed on the diagnosis of SPTD, there was a consensus on the case being compensated or decompensated and being symptomatic or asymptomatic. CONCLUSIONS: There was strong agreement in 5 out of 7 cases on the presence of the diagnosis of clinically relevant SPTD. Among spine experts, there is a strong consensus to use CT scan and MR scan, a cervical CR for C-cases, and a full spine CR for ThL-cases. The lack of agreement on items of the medical history suggests that a Delphi study can help us reach a consensus on the essential items of clinically relevant SPTD. LEVEL OF EVIDENCE: Level V.

Validation of the Hierarchical Nature of the AO Spine Sacral Classification and the Development of the Sacral AO Spine Injury Score.

STUDY DESIGN: Global cross-sectional survey. OBJECTIVE: The objective of this study was to validate the hierarchical nature of the AO Spine Sacral Classification System and develop an injury scoring system. SUMMARY OF BACKGROUND DATA: Although substantial interobserver and intraobserver reliability of the AO Spine Sacral Classification System has been established, the hierarchical nature of the classification has yet to be validated. METHODS: Respondents numerically graded each variable within the classification system for severity. Based on the results, a Sacral AO Spine Injury Score (AOSIS) was developed. RESULTS: A total of 142 responses were received. The classification exhibited a hierarchical Injury Severity Score (ISS) progression (A1: 8 to C3: 95) with few exceptions. Subtypes B1 and B2 fractures showed no significant difference in ISS (B1 43.9 vs. B2 43.4, P =0.362). In addition, the transitions A3→B1 and B3→C0 represent significant decreases in ISS (A3 66.3 vs. B1 43.9, P <0.001; B3 64.2 vs. C0 46.4, P <0.001). Accordingly, A1 injury was assigned a score of 0. A2 and A3 received scores of 1 and 3 points, respectively. Posterior pelvic injuries B1 and B2 both received a score of 2. B3 received a score of 3 points. C0, C1, C2, and C3 received scores of 2, 3, 5, and 6 points, respectively. The scores assigned to neurological modifiers N0, N1, N2, N3, and NX were 0, 1, 2, 4, and 3, respectively. Case-specific modifiers M1, M2, M3, and M4 received scores of 0, 0, 1, and 2 points, respectively. CONCLUSIONS: The results of this study validate the hierarchical nature of the AO Spine Sacral Classification System. The Sacral AOSIS sets the foundation for further studies to develop a universally accepted treatment algorithm for the treatment of complex sacral injuries. LEVEL OF EVIDENCE: Level IV-Diagnostic.

Does Erector Spinae Plane Block Decrease Analgesia Requirements After Minimal-Invasive Posterior Transpedicular Stabilization in Patients With Vertebral Body Fracture? A Prospective, Randomized, Double-Blind Controlled Study.

STUDY DESIGN: Prospective randomized placebo controlled double blind trial. OBJECTIVE: To examine the effect of ESP block after minimally invasive posterior stabilization for vertebral fractures on opioid consumption, pain, blood loss, disability level, and wound healing complications. METHODOLOGY: Patients indicated for minimal invasive posterior stabilisation were included to the study. Our primary outcome was the opioid consumption and Visual Analogue Scale (VAS) measured during the first 48 hours. Secondary outcomes used to measure the short-term outcome included Oswestry Disability Index (ODI) and Patient Reported Outcome Spine Trauma (PROST). RESULTS: In total, 60 patients were included with a 93.3% follow-up. Average morphine consumption during the PACU (Post Anaesthesia Care Unit) period was 5.357 mg in ESP group and 8.607 mg in placebo group (P = .004). Average VAS during first 24 hour was 3.944 in ESP group and 5.193 in placebo group (P = .046). Blood loss was 14.8 g per screw in ESP group and 15.4 g in placebo group (P = .387). The day2 PROST value was 33.9 in ESP group and 28.8 in placebo group (P = .008) and after 4 weeks 55.2 in ESP group and 49.9 in placebo group (P = .036). No significant differences in ODI were detected. CONCLUSION: The use of ESP block in minimally invasive spinal surgery for posterior fracture stabilization leads to a significant reduction of opioid consumption during PACU stay by 37.7%. Reduction of opioid consumption was accompanied with lower pain (VAS). We found positive effect of the ESP block on short term outcome scores, but no effect on perioperative blood loss and wound healing.

Georg Schmorl prize of the German spine society (DWG) 2022: current treatment for inpatients with osteoporotic thoracolumbar fractures-results of the EOFTT study.

AIM: Osteoporotic thoracolumbar fractures are of increasing importance. To identify the optimal treatment strategy this multicentre prospective cohort study was performed. PURPOSE: Patients suffering from osteoporotic thoracolumbar fractures were included. Excluded were tumour diseases, infections and limb fractures. Age, sex, trauma mechanism, OF classification, OF-score, treatment strategy, pain condition and mobilization were analysed. METHODS: A total of 518 patients' aged 75 ± 10 (41-97) years were included in 17 centre. A total of 174 patients were treated conservatively, and 344 were treated surgically, of whom 310 (90%) received minimally invasive treatment. An increase in the OF classification was associated with an increase in both the likelihood of surgery and the surgical invasiveness. RESULTS: Five (3%) complications occurred during conservative treatment, and 46 (13%) occurred in the surgically treated patients. 4 surgical site infections and 2 mechanical failures requested revision surgery. At discharge pain improved significantly from a visual analogue scale score of 7.7 (surgical) and 6.0 (conservative) to a score of 4 in both groups (p < 0.001). Over the course of treatment, mobility improved significantly (p = 0.001), with a significantly stronger (p = 0.007) improvement in the surgically treated patients. CONCLUSION: Fracture severity according to the OF classification is significantly correlated with higher surgery rates and higher invasiveness of surgery. The most commonly used surgical strategy was minimally invasive short-segmental hybrid stabilization followed by kyphoplasty/vertebroplasty. Despite the worse clinical conditions of the surgically treated patients both conservative and surgical treatment led to an improved pain situation and mobility during the inpatient stay to nearly the same level for both treatments.

The role of routine transpedicular biopsies during kyphoplasty or vertebroplasty for vertebral compression fractures in the detection of malignant diseases: a systematic review.

INTRODUCTION: Procedures like kyphoplasty or vertebroplasty have become an established treatment option for vertebral compression fractures (VCF). The transpedicular approach used during these procedures allows to take biopsies from the affected vertebral body. The aim of this study was to systematically summarize the existing knowledge on the value of routine transpedicular biopsies during kyphoplasty or vertebroplasty for vertebral compression fractures. METHODS: A systematic review of the literature using PubMed/Medline databases with the goal of finding all articles describing the value trans-pedicular biopsies for detecting primary bone tumors, metastases, bone diseases, or spondylitis in patients with vertebral compression fractures was performed. Search terms were (*biopsy/ OR biops*.ti,ab.) AND (vertebral compression fracture*.ti,ab.). RESULTS: Sixteen articles met the inclusion criteria, among these were six prospective and ten retrospective case series. Publication dates ranged from 2005 to 2020. A total of 3083 patients with 3667 transpedicular biopsies performed were included. Most biopsies confirmed osteoporosis as the dominant underlying pathology of VCFs. Transpedicular biopsies revealed an unexpected malignant diagnosis in 0.4-6% of the cases. CONCLUSION: Routine transpedicular biopsies during kyphoplasty or vertebroplasty detect unexpected malignant lesions in 0.4-6% of the patients, even though the definition of "unexpected" varies among the analyzed studies. The evidence to support a routine biopsy is inconsistent. Nevertheless, routine biopsies can be considered, especially when sufficient preoperatvie imaging is not available or radiological findings are unclear.

[Value of routine transpedicular biopsies in kyphoplasty and vertebroplasty for vertebral compression fractures : A survey among 250 spine surgeons]. / Stellenwert der transpedikulären Biopsie bei Kypho- und Vertebroplastien von Wirbelkörperfrakturen : Eine Umfrage unter 250 Wirbelsäulenchirurgen.

BACKGROUND: Transpedicular cement augmentation is an established therapeutic option in the treatment of pathologic compression fractures of the spine. In addition to osteoporosis, underlying metastatic diseases or, more rarely, a primary bone tumor are recurrent causes of vertebral compression fractures without adequate trauma. OBJECTIVE: To obtain a current opinion among spine surgeons in Germany, Switzerland, and Austria on the value of transpedicular biopsy during kyphoplasty and vertebroplasty of vertebral body fractures. MATERIAL AND METHODS: A web-based (UmfrageOnline®) questionnaire with 11 questions was created and sent to the email distribution lists of the German Spine Society (DWG), the Austrian Society for Spine Surgery (spine.at), and the Swiss Society for Spinal Surgery (SGS), as well as to the email distribution list of the Spine Section of the German Society for Orthopedics and Trauma Surgery (DGOU). RESULTS: Of a total of 2675 spine surgeons contacted 250 (9.3%) responded to the survey. Approximately one third (29.8%) of respondents regularly perform a transpedicular biopsy with each kyphoplasty or vertebroplasty. Reasons cited for biopsy were image morphology (79.7%) or history of suspected (66.0%) or present (71.4%) tumor disease. Reasons cited against routine biopsy were the associated costs and the limited informative value of the biopsies obtained. DISCUSSION: Nearly one third of the spine surgeons surveyed regularly perform a transpedicular biopsy with each kyphoplasty or vertebroplasty. Almost all respondents perform biopsies at least when there is an imaging morphologic suspicion of tumor disease or tumor disease is known or suspected based on risk factors. Future studies need to further clarify the cost-effectiveness of transpedicular biopsy.

Open Posterior Reduction and Stabilization of AO Spine C3 Sacral Fractures.

AO Spine C3 sacral fractures are defined by separation of the spine including S1 from the pelvic ring and are usually result of a high-energy injury. Besides their high biomechanical instability and high rate of associated neurological impairment, these fractures are often extremely difficult to reduce due to severe bony impaction and dislocation. Additional difficulties in management of these fractures arise from only a thin-layer of soft-tissue coverage overlying the injured area.

Spinal Post-traumatic Deformity: An International Expert Survey Among AO Spine Knowledge Forum Members.

STUDY DESIGN: Survey among spine experts. OBJECTIVE: To investigate the different views and opinions of clinically relevant spinal post-traumatic deformity (SPTD). SUMMARY OF BACKGROUND DATA: There is no clear definition of clinically relevant SPTD. This leads to a wide variation in characteristics used for diagnosis and treatment indications of SPTD. To understand the current concepts of SPTD a survey was conducted among spine trauma surgeons. METHODS: Members of the AO Spine Knowledge Forum Trauma participated in an online survey. The survey was divided in 4 domains: Demographics, criteria to define SPTD, risk factors, and management. The data were collected anonymously and analyzed using descriptive statistics, absolute, and relative frequencies. Consensus on dichotomous outcomes was set to 80% of agreement. RESULTS: Fifteen members with extensive experience in treatment of spinal trauma participated, representing the 5 AO Spine Regions. Back pain was the only criterion for definition of SPTD with complete agreement. Consensus (≥80%) was reached for kyphotic angulation outside normative ranges and impaired function. Eighty-seven percent and 100% agreed that a full-spine conventional radiograph was necessary in diagnosing and treating SPTD, respectively. The "missed B-type injury" was rated at most important by all but 1 participant. There was no agreement on other risk factors leading to clinically relevant SPTD. Concerning the management, all participants agreed that an asymptomatic patient should not undergo surgical treatment and that neurological deficit is an absolute surgical indication. For most of the participants the preferred surgical treatment of acute injury in all spine regions but the subaxial region is posterior fixation. CONCLUSION: Some consensus exists among leading experts in the field of spine trauma care concerning the definition, diagnosis, risk factors, and management of SPTD. This study acts as the foundation for a Delphi study among the global spine community.

Concomitant injuries in patients with thoracic vertebral body fractures-a systematic literature review.

PURPOSE: The aim of this study was to give a systematic overview over the rate and location of concomitant injuries, the probability of suffering from neurological deficits, and to give evidence of the timing of surgery in severely injured patients with unstable thoracic vertebral body fractures. METHODS: This review is based on articles retrieved by a systematic search in the PubMed and Web of Science database for publications up to November 2020 dealing with unstable fractures of the mid-thoracic spine. RESULTS: Altogether, 1109 articles were retrieved from the literature search. A total of 1095 articles were excluded. Thus, 16 remaining original articles were included in this systematic review depicting the topics timing of surgery in polytraumatized patients, outcome neurologic deficits, and impact of concomitant injuries. The overall level of evidence of the vast majority of studies is low. CONCLUSION: The evidence of the available literature is low. The cited studies reveal that thoracic spinal fractures are associated with a high number of neurological deficits and concomitant injuries, particularly of the thoracic cage and the lung. Thereby, diagnostic algorithm should include computer tomography of the whole thoracic cage if there is any clinical sign of concomitant injuries. Patients with incomplete neurologic deficits benefit from early surgery consisting of decompression and long-segmental stabilization.

Update on Upper Cervical Injury Classifications: The New AO Upper Cervical Spine Classification System.

The upper cervical spine accounts for the largest proportion of cervical range of motion afforded by a complex system of bony morphology and ligamentous stability. Its unique anatomy, however, also makes it particularly vulnerable during both low and high energy trauma. Trauma to this area, referred to as upper cervical spine trauma, can disrupt the stability of the upper cervical spine and result in a wide spectrum of injury. Numerous upper cervical injury classification systems have been proposed, each of which have distinct limitations and drawbacks that have prevented their universal adoption. In this article, we provide an overview of previous classifications, with an emphasis on the development of the new AO Spine Upper Cervical Classification System (AO Spine UCCS).

Biomechanics and clinical outcome after posterior stabilization of mid-thoracic vertebral body fractures: a systematic literature review.

PURPOSE: The aim of this review is to systematically screen the literature for clinical and biomechanical studies dealing with posterior stabilization of acute traumatic mid-thoracic vertebral fractures in patients with normal bone quality. METHODS: This review is based on articles retrieved by a systematic search in the PubMed and Web of Science database for publications up to December 2018 dealing with the posterior stabilization of fractures of the mid-thoracic spine. RESULTS: Altogether, 1012 articles were retrieved from the literature search. A total of 960 articles were excluded. A total of 16 articles were dealing with the timing of surgery in polytraumatized patients, patients suffering of neurologic deficits after midthoracic fractures, and the impact of concomitant thoracic injuries and were excluded. Thus, 36 remaining original articles were included in this systematic review depicting the topics biomechanics, screw insertion, and outcome after posterior stabilization. The overall level of evidence of the vast majority of studies is low. CONCLUSION: High quality studies are lacking. Long-segmental stabilization is indicated in unstable midthoracic fractures with concomitant sternal fractures. Generally, long-segmental constructs seem to be the safer treatment strategy considering the relative high penetration rate of pedicle screws in this region. Thereby, navigated insertion techniques and intraoperative 3D-imaging help to improve pedicle screw placement accuracy.

Description and Reliability of the AOSpine Sacral Classification System.

BACKGROUND: Several classification systems exist for sacral fractures; however, these systems are primarily descriptive, are not uniformly used, have not been validated, and have not been associated with a treatment algorithm or prognosis. The goal of the present study was to demonstrate the reliability of the AOSpine Sacral Classification System among a group of international spine and trauma surgeons. METHODS: A total of 38 sacral fractures were reviewed independently by 18 surgeons selected from an expert panel of AOSpine and AOTrauma members. Each case was graded by each surgeon on 2 separate occasions, 4 weeks apart. Intrarater reproducibility and interrater agreement were analyzed with use of the kappa statistic (κ) for fracture severity (i.e., A, B, and C) and fracture subtype (e.g., A1, A2, and A3). RESULTS: Seventeen reviewers were included in the final analysis, and a total of 1,292 assessments were performed (646 assessments performed twice). Overall intrarater reproducibility was excellent (κ = 0.83) for fracture severity and substantial (κ = 0.71) for all fracture subtypes. When comparing fracture severity, overall interrater agreement was substantial (κ = 0.75), with the highest agreement for type-A fractures (κ = 0.95) and the lowest for type-C fractures (κ = 0.70). Overall interrater agreement was moderate (κ = 0.58) when comparing fracture subtype, with the highest agreement seen for A2 subtypes (κ = 0.81) and the lowest for A1 subtypes (κ = 0.20). CONCLUSIONS: To our knowledge, the present study is the first to describe the reliability of the AOSpine Sacral Classification System among a worldwide group of expert spine and trauma surgeons, with substantial to excellent intrarater reproducibility and moderate to substantial interrater agreement for the majority of fracture subtypes. These results suggest that this classification system can be reliably applied to sacral injuries, providing an important step toward standardization of treatment.

[Hounsfield units as a measure of bone density-applications in spine surgery]. / "Hounsfield units" als Maß für die Knochendichte ­ Anwendungsmöglichkeiten in der Wirbelsäulenchirurgie.

Despite today's good diagnostic and therapeutic options for osteoporosis, the number of unidentified cases is very high and therapy is therefore usually inadequate. Frequently, the diagnosis of osteoporosis is made only after the occurrence of a fracture. The reason for this, apart from the costs incurred as well as the additional radiation exposure of the diagnostics, is certainly the limited availability of dual energy X­ray absorptiometry (DEXA) as well as quantitative computed tomography (q-CT). In search of an alternative technique, Hounsfield units (HU) of the clinical CT examination proved to be ground-breaking: the results of previous investigations demonstrated a reliable correlation between the T values of the DEXA measurement and the HU of the same vertebral body. Due to the widespread use of clinical CT scans of the thorax and the abdomen for a variety of indications, it is expected that the number of unidentified cases of osteoporosis can be significantly reduced-without additional costs and radiation exposure associated with osteoporosis screening. In addition to osteoporosis diagnostics, the calculated HU may also provide better preoperative planning as well as predicting the further course of the disease. Thus, the risk for vertebral body fractures, screw loosening and cage sintering after ventral fusion operations can be sufficiently predicted. In this way, preoperative modifications to the surgical procedure can be made to reduce the risk of implant failure.

Does Riluzole Influence Bone Formation?: An In Vitro Study of Human Mesenchymal Stromal Cells and Osteoblast.

STUDY DESIGN: A post-test design biological experiment. OBJECTIVE: The aim of this study was to evaluate the osteogenic effects of riluzole on human mesenchymal stromal cells and osteoblasts. SUMMARY OF BACKGROUND DATA: Riluzole may benefit patients with spinal cord injury (SCI) from a neurologic perspective, but little is known about riluzole's effect on bone formation, fracture healing, or osteogenesis. METHODS: Human mesenchymal stromal cells (hMSCs) and human osteoblasts (hOB) were obtained and isolated from healthy donors and cultured. The cells were treated with riluzole of different concentrations (50, 150, 450 ng/mL) for 1, 2, 3, and 4 weeks. Cytotoxicity was evaluated as was the induction of osteogenic differentiation of hMSCs. Differentiation was evaluated by measuring alkaline phosphatase (ALP) activity and with Alizarin red staining. Osteogenic gene expression of type I collagen (Col1), ALP, osteocalcin (Ocn), Runx2, Sox9, Runx2/Sox9 ratio were measured by qRT-PCR. RESULTS: No cytotoxicity or increased proliferation was observed in bone marrow derived hMSCs and primary hOBs cultured with riluzole over 7 days. ALP activity was slightly increased in hMSCs after treatment for 2 weeks with riluzole 150 ng/mL and slightly upregulated by 150% (150 ng/mL) and 90% (450 ng/mL) in hMSCs at 3 weeks. In hOBs, ALP activity almost doubled after 2 weeks of culture with riluzole 150 ng/mL (P < 0.05). More pronounced 2.6-fold upregulation was noticed after 3 weeks of culture with riluzole at both 150 ng/mL (P = 0.05) and 450 ng/mL (P = 0.05). No significant influence of riluzole on the mRNA expression of osteocalcin (OCN) was observed. CONCLUSION: The effect of riluzole on bone formation is mixed; low-dose riluzole has no effect on the viability or function of either hMSCs or hOBs. The activity of ALP in both cell types is upregulated by high-dose riluzole, which may indicate that high-dose riluzole can increase osteogenic metabolism and subsequently accelerate bone healing process. However, at high concentrations, riluzole leads to a decrease in osteogenic gene expression, including Runx2 and type 1 collagen. LEVEL OF EVIDENCE: N/A.

The surgical algorithm for the AOSpine thoracolumbar spine injury classification system.

PURPOSE: The goal of the current study is to establish a surgical algorithm to accompany the AOSpine thoracolumbar spine injury classification system. METHODS: A survey was sent to AOSpine members from the six AO regions of the world, and surgeons were asked if a patient should undergo an initial trial of conservative management or if surgical management was warranted. The survey consisted of controversial injury patterns. Using the results of the survey, a surgical algorithm was developed. RESULTS: The AOSpine Trauma Knowledge forum defined that the injuries in which less than 30% of surgeons would recommend surgical intervention should undergo a trial of non-operative care, and injuries in which 70% of surgeons would recommend surgery should undergo surgical intervention. Using these thresholds, it was determined that injuries with a thoracolumbar AOSpine injury score (TL AOSIS) of three or less should undergo a trial of conservative treatment, and injuries with a TL AOSIS of more than five should undergo surgical intervention. Operative or non-operative treatment is acceptable for injuries with a TL AOSIS of four or five. CONCLUSION: The current algorithm uses a meaningful injury classification and worldwide surgeon input to determine the initial treatment recommendation for thoracolumbar injuries. This allows for a globally accepted surgical algorithm for the treatment of thoracolumbar trauma.

Can a Thoracolumbar Injury Severity Score Be Uniformly Applied from T1 to L5 or Are Modifications Necessary?

Study Design Literature review. Objective The aim of this review is to highlight challenges in the development of a comprehensive surgical algorithm to accompany the AOSpine Thoracolumbar Spine Injury Classification System. Methods A narrative review of the relevant spine trauma literature was undertaken with input from the multidisciplinary AOSpine International Trauma Knowledge Forum. Results The transitional areas of the spine, in particular the cervicothoracic junction, pose unique challenges. The upper thoracic vertebrae have a transitional anatomy with elements similar to the subaxial cervical spine. When treating these fractures, the surgeon must be aware of the instability due to the junctional location of these fractures. Additionally, although the narrow spinal canal makes neurologic injuries common, the small pedicles and the inability to perform an anterior exposure make decompression surgery challenging. Similarly, low lumbar fractures and fractures at the lumbosacral junction cannot always be treated in the same manner as fractures in the more cephalad thoracolumbar spine. Although the unique biomechanical environment of the low lumbar spine makes a progressive kyphotic deformity less likely because of the substantial lordosis normally present in the low lumbar spine, even a fracture leading to a neutral alignment may dramatically alter the patient's sagittal balance. Conclusion Although the new AOSpine Thoracolumbar Spine Injury Classification System was designed to be a comprehensive thoracolumbar classification, fractures at the cervicothoracic junction and the lumbosacral junction have properties unique to these junctional locations. The specific characteristics of injuries in these regions may alter the most appropriate treatment, and so surgeons must use clinical judgment to determine the optimal treatment of these complex fractures.

Decompression and paraspinous tension band: a novel treatment method for patients with lumbar spinal stenosis and degenerative spondylolisthesis.

BACKGROUND CONTEXT: Prior studies have demonstrated the superiority of decompression and fusion over decompression alone for the treatment of lumbar degenerative spondylolisthesis with spinal stenosis. More recent studies have investigated whether nonfusion stabilization could provide durable clinical improvement after decompression and fusion. PURPOSE: To examine the clinical safety and effectiveness of decompression and implantation of a novel flexion restricting paraspinous tension band (PTB) for patients with degenerative spondylolisthesis. STUDY DESIGN: A prospective clinical study. PATIENT SAMPLE: Forty-one patients (7 men and 34 women) aged 45 to 83 years (68.2 ± 9.0) were recruited with symptomatic spinal stenosis and Meyerding Grade 1 or 2 degenerative spondylolisthesis at L3-L4 (8) or L4-L5 (33). OUTCOME MEASURES: Self-reported measures included visual analog scale (VAS) for leg, back, and hip pain and the Oswestry Disability Index (ODI). Physiologic measures included quantitative and qualitative radiographic analysis performed by an independent core laboratory. METHODS: Patients with lumbar degenerative spondylolisthesis and stenosis were prospectively enrolled at four European spine centers with independent monitoring of data. Clinical and radiographic outcome data collected preoperatively were compared with data collected at 3, 6, 12, and 24 months after surgery. This study was sponsored by the PTB manufacturer (Simpirica Spine, Inc., San Carlos, CA, USA), including institutional research support grants to the participating centers totaling approximately US $172,000. RESULTS: Statistically significant improvements and clinically important effect sizes were seen for all pain and disability measurements. At 24 months follow-up, ODI scores were reduced by an average of 25.4 points (59%) and maximum leg pain on VAS by 48.1 mm (65%). Back pain VAS scores improved from 54.1 by an average of 28.5 points (53%). There was one postoperative wound infection (2.4%) and an overall reoperation rate of 12%. Eighty-two percent patients available for 24 months follow-up with a PTB in situ had a reduction in ODI of greater than 15 points and 74% had a reduction in maximum leg pain VAS of greater than 20 mm. According to Odom criteria, most of these patients (82%) had an excellent or good outcome with all except one patient satisfied with surgery. As measured by the independent core laboratory, there was no significant increase in spondylolisthesis, segmental flexion-extension range of motion, or translation and no loss of lordosis in the patients with PTB at the 2 years follow-up. CONCLUSIONS: Patients with degenerative spondylolisthesis and spinal stenosis treated with decompression and PTB demonstrated no progressive instability at 2 years follow-up. Excellent/good outcomes and significant improvements in patient-reported pain and disability scores were still observed at 2 years, with no evidence of implant failure or migration. Further study of this treatment method is warranted to validate these findings.