Sequential damage assessment of the different components of the posterior ligamentous complex after magnetic resonance imaging interpretation: prospective study 74 traumatic fractures

Revisiting Post-Laminectomy Kyphosis and Challenges in Its Management: A Case Report

The posterior ligamentous complex plays a pivotal role in spinal stability during complex movements, especially at the cervical vertebral level. Its disruption leads to the development of post-laminectomy kyphosis. The present case emphasizes the challenges in managing post-laminectomy kyphosis, restoring spinal alignment, and the importance of the posterior tension band as a spine stabilizer. A 19-year-old male underwent C2-C5 laminectomy for cervical C3 neurofibroma at an outside hospital. The patient remained stable for five months and then developed cervical kyphosis, leading to myelopathy. Clinical examination revealed significant neurological deficits, including spasticity, clonus, loss of hand dexterity, and sensory abnormalities. Imaging revealed C3 retrolisthesis with severe cervical kyphosis, cord compression, and myelomalacia. The management involved cervical traction with gradual increments in the weight and correction of the cervical sagittal balance. Principles of kyphotic deformity correction were applied, and C2 pedicle with C3-C5 lateral mass fixation was performed. The patient's modified Japanese Orthopaedic Association score improved from 10 to 16 at six months' follow-up. Post-laminectomy, the disruption of the posterior ligamentous complex increases the range of motion, particularly in the cervical spine, leading to instability and kyphosis. Surgical interventions such as laminoplasty, laminotomy, and laminectomy with posterior cervical fusion aim to mitigate the risk of kyphosis, with techniques such as bone-to-bone ligament-preserving laminoplasty and ultrasonic bone scalpel showing promise in further reducing the risk of kyphosis. The key determinant for the prevention of kyphosis is the integrity of the posterior ligamentous complex. The management of cervical kyphosis includes appropriate pre-operative planning, which includes the evaluation of cervical and spinopelvic parameters. For a posterior spinal approach, one may choose to consider laminotomy, laminoplasty, or laminectomy along with posterior cervical fusion.

The Relationship Between MRI Findings of Posterior Ligamentous Complex and Lumbar Instability in Degenerative Spondylolisthesis

Background

To determine the factors in posterior ligamentous complex indicating lumbar instability in patients diagnosed with degenerative spondylolisthesis on conventional magnetic resonance imaging (MRI).

Methods

We retrospectively analyzed patients who underwent PLIF surgery for degenerative spondylolisthesis at our institution between 2018 and 2020 and who had complete eligible preoperative imaging data for review and study, including lumbar MRI and anteroposterior and flexion-extension radiographs.

Results

Fifty-three patients were confirmed to have lumbar instability (Unstable Group, 44%), while sixty-seven patients (Stable Group, 56%) did not have instability on radiographs. The patients in the stable group had more advanced status of the degeneration of intervertebral disc than in the unstable group (p<0.05). The degeneration of supraspinous ligament (SSL) was more severe in the unstable group (p<0.05). Compared with the patients with rotatory instability, advanced degeneration of interspinous ligament (ISL) and SSL was observed in patients with translatory instability (p<0.05). However, there was no significant difference with regard to the height of the spinous process and the interspinous distance in patients with or without instability.

Conclusion

This MRI analysis showed that abnormal segmental motion is closely associated with the pathological characteristics of supraspinal ligament. Advanced degeneration of SSL in patients with degenerative spondylolisthesis should raise the suspicion for lumbar instability and additional evaluations. The status of ISL and ligamentum flavum (LF) may not be helpful for the diagnosis of lumbar instability. Functional radiographs combined with MRI may provide valuable information when diagnosing lumbar instability in patients with mechanical back pain.

Towards a standardized reporting of the impact of magnetic resonance imaging on the decision-making of thoracolumbar fractures without neurological deficit: Conceptual framework and proposed methodology

Introduction

A recent meta-analysis showed that only four prior studies have shown that magnetic resonance imaging (MRI) can change the fracture classification in 17% and treatment decisions in 22% of cases. However, previous studies showed a wide methodological variability regarding the study population, the definition of posterior ligamentous complex (PLC) injury, and outcome measures.

Research question

How can we standardize the reporting of the impact of MRI for neurologically intact patients with thoracolumbar fractures?

Material and methods

All available literature regarding the impact of MRI on thoracolumbar fracture classification or decision-making were reviewed. Estimating the impact of MRI on the TLFs' classification is an exercise of analyzing the CTs' accuracy for PLC injury against MRI as a ''Gold standard''and should follow standardized checklists such as the Standards for the Reporting of Diagnostic Accuracy Studies. Additionally, specific issues related to TLFs should be addressed.

Results

A standardized approach for reporting the impact of MRI in neurologically intact TLF patients was proposed. Regarding patient selection, restricting the inclusion of neurologically intact patients with A- and B-injuries is crucial. Image interpretation should be standardized regarding imaging protocol and appropriate criteria for PLC injury. The impact of MRI can be measured by either the rate of change in fracture classification or treatment decisions; the cons and pros of each measure is thoroughly discussed.

Discussion and conclusion

We proposed a structured methodology for examining the impact of MRI on neurologically intact patients with TLFs, focusing on appropriate patient selection, standardizing image analysis, and clinically relevant outcome measures.

Post-traumatic lumbar nerve root entrapment into the spinous process of the lumbar spine

Thoracolumbar fractures constitute a significant portion of spinal trauma, accounting for 15-20% of the cases. These fractures, caused by high-impact injuries, may involve tears of the posterior ligamentous complex, presenting a high chance of neurological injury ranging from dural tears to spinal root avulsion. This case report discusses a rare occurrence of avulsion of lumbosacral nerve roots posteriorly, becoming entrapped in the fractured spinous process of the L2 lumbar vertebra, leading to cauda equina syndrome following trauma and its implications during surgery.

Unilateral biportal endoscopic technique combined with percutaneous transpedicular screw fixation for thoracolumbar burst fractures with neurological symptoms: technical note and preliminary report

BACKGROUND

Previous studies on thoracolumbar fractures with neurological symptoms have focused on how to achieve satisfactory fracture reduction, adequate nerve decompression, and stable spinal alignment. With the development of the minimally invasive spine surgery technique, achieving satisfactory treatment results and reducing iatrogenic trauma at the same time has become a new goal of spinal surgery. This research used percutaneous transpedicular screw distraction to partially reduce the fractured vertebrae, followed by completing nerve decompression and reducing residual displacement bone fragments with the assistance of the unilateral biportal endoscopic (UBE) technique to achieve full protection of bone-ligament tissue and obtain good clinical efficacy.

METHODS

Guide wires were safely inserted into the fractured vertebra and adjacent upper and lower vertebra under the surveillance of anteroposterior and lateral X-ray fluoroscopy. Transpedicular screws were implanted via guide wires on the side with mild neurological deficits or bone fragment compression (the opposite side of the endoscopic operation). A titanium rod was installed and moderately distracted to reduce the fractured vertebra. Then, under the guidance of the endoscopic view, the laminectomy and ligamentum flavum resection were completed according to the position of the protruding bone fragment into the spinal canal, and the compressed dural sac or nerve root was fully exposed and decompressed. An L-shaped replacer was used to reduce residual bone fragments. The ipsilateral transpedicular screws and rod were installed and adjusted to match the contralateral side. The drainage tube was indwelled, and the incision was closed. The preoperative and postoperative images of the patients were evaluated, and the recovery of neurological symptoms was observed.

RESULTS

Surgery was successfully completed on all six patients, and no intraoperative conversion to open surgery was performed. Postoperative images showed good reduction of the protruding bone fragment and good placement of all screws. At the last follow-up, the neurological symptoms of all patients returned to normal.

CONCLUSION

The UBE technique combined with percutaneous transpedicular screw fixation in the treatment of thoracolumbar fractures with neurological symptoms can effectively achieve the reduction of displaced bone fragments, improve damaged nerve function, stabilize spinal alignment, and protect the integrity of bone-ligament tissue.

A Proposal for a Standardized Imaging Algorithm to Improve the Accuracy and Reliability for the Diagnosis of Thoracolumbar Posterior Ligamentous Complex Injury in Computed Tomography and Magnetic Resonance Imaging

STUDY DESIGN

Systematic Literature Review.

OBJECTIVE

To propose a systematic imaging algorithm for diagnosing posterior ligamentous complex (PLC) injury in computed tomography (CT) and magnetic resonance imaging (MRI) to improve the reliability of PLC assessment.

METHODS

A systematic review was conducted following PRISMA guidelines. The Scopus database was searched from its inception until July 21, 2022, for studies evaluating CT or MRI assessment of the PLC injury following thoracolumbar trauma. The studies extracted key findings, objectives, injury definitions, and radiographic modalities.

RESULTS

Twenty-three studies were included in this systematic review, encompassing 2021 patients. Five studies evaluated the accuracy of MRI in detecting thoracolumbar PLC injury using intraoperative findings as a reference. These studies indicate that black stripe discontinuity due to supraspinous or ligamentum flavum rupture is a more specific criterion of PLC injury than high-signal intensity. Thirteen papers evaluated the accuracy or reliability of CT in detecting thoracolumbar PLC injury using MRI or intraoperative findings as a reference. The overall accuracy rate of CT in detecting PLC injury was 68-90%. Two studies evaluate the accuracy of combined CT findings, showing that ≥2 CT findings are associated with a positive predictive value of 88-91 %. Vertebral translation, facet joint malalignment, spinous process fracture, horizontal laminar fracture, and interspinous widening were independent predictors of PLC injury.

CONCLUSION

We provided a comprehensive imaging algorithm for diagnosing PLC in CT and MRI based on available literature and our experience. The algorithm will potentially improve the accuracy and reliability of PLC assessment, however it needs multicentre prospective validation.

Which Morphological Features of Facet Diastasis Predict Thoracolumbar Posterior Ligamentous Complex Injury as Defined by Magnetic Resonance Imaging?

BACKGROUND

The association of various morphological features of facet diastasis with posterior ligamentous complex (PLC) injury has not been previously described. This study aims to determine the diagnostic value of facet diastasis subtypes for diagnosing thoracolumbar PLC injury.

METHODS

We retrospectively reviewed 337 consecutive patients with acute thoracolumbar fractures who had computed tomography (CT) and magnetic resonance imaging (MRI) within 10 days of injury. Three and 5 reviewers evaluated MRI and CT images, respectively. Facet diastasis was subclassified as follows: Dislocated, no articular surface apposition; subluxed, incomplete articular surface apposition; and facet fracture articular process fractures which may be displaced ≥2 mm or otherwise undisplaced, facet joint widening (FJW) ≥ 3 mm. We examined the diagnostic accuracy and the multivariate associations of facet diastasis subtypes with PLC injury in MRI.

RESULTS

Facet dislocation, subluxation, and displaced facet fracture yielded a high positive predictive value (PPV) for PLC injury (96%, 88%, and 94%, respectively). In contrast, undisplaced facet fracture and FJW yielded a moderate PPV for PLC injury (78%, and 45%, respectively). Facet dislocation, subluxation, and displaced facet fracture showed independent associations with PLC injury (adjusted odds ratio [AOR] = 38.4, 17.1, 13.4, respectively; P < 0.05). Undisplaced facet fracture and FJW were not associated with PLC injury (AOR = 3.9 [95% confidence interval, 0.49-38.4], P = 0.20) and (AOR = 1.94 [95% confidence interval, 0.48-7.13]; P = 0.20; P = 0.33), respectively.

CONCLUSIONS

Facet dislocation, subluxation, and displaced facet fracture, but not undisplaced facet fracture or FJW, were independently associated with PLC injury. Therefore, we propose to define facet diastasis as a surrogate marker of PLC injury in MRI based on these morphologies.

Magnetic Resonance Imaging for Spine Emergencies

This article is devoted to the MR imaging evaluation of spine emergencies, defined as spinal pathologic conditions that pose an immediate risk of significant morbidity or mortality to the patient if not diagnosed and treated in a timely manner. MR imaging plays a central role in the timely diagnosis of spine emergencies. A summary of MR imaging indications and MR imaging protocols tailored for a variety of spinal emergencies will be presented followed by a review of key imaging findings for the most-encountered emergent spine pathologic conditions. Pathologic conditions will be broadly grouped into traumatic and atraumatic pathologic conditions. For traumatic injuries, a practical and algorithmic diagnostic approach based on the AO Spine injury classification system will be presented focused on subaxial spine trauma. Atraumatic spinal emergencies will be dichotomized into compressive and noncompressive subtypes. The location of external compressive disease with respect to the thecal sac is fundamental to establishing a differential diagnosis for compressive emergencies, whereas specific patterns of spinal cord involvement on MR imaging will guide the discussion of inflammatory and noninflammatory causes of noncompressive myelopathy.

Clinical significance of "positive" cervical spine MRI findings following a negative CT

PURPOSE

To review and analyze the clinical significance of positive acute traumatic findings seen on MRI of the cervical spine (MRCS) following a negative CT of the cervical spine (CTCS) for trauma.

METHODS

We performed a sub-cohort analysis of 54 patients with negative CTCS and a positive MRCS after spine trauma from the previous multicenter study of the Research Consortium of New England Centers for Trauma (ReCONECT). Both CTCS and MRCS were independently reviewed by two emergency radiologists and two spine surgeons. The surgeons also commented on the clinical significance of the traumatic findings seen on MRCS and grouped them into unstable, potentially unstable, and stable injuries.

RESULTS

Among 35 unevaluable patients, MRCS showed one unstable (hyperextension) and two potentially unstable (hyperflexion) injuries. Subtle findings were seen on CTCS in 2 of 3 patients upon careful retrospective review that would have suggested these injuries. Of 19 patients presenting with cervicalgia, 2/5 (40%) patients with neurological deficit demonstrated clinically significant findings on MRCS with predisposing factors seen on CT. None of the 14 patients with isolated cervicalgia and no neurological deficit had clinically significant findings on their MRCS.

CONCLUSION

While CTCS is adequate for clearing the cervical spine in patients with isolated cervicalgia, MRCS can play a critical role in patients with neurological deficits and normal CTCS. Clinically significant traumatic findings were seen in 8.5% of unevaluable patients on MRCS, though these injuries in fact could be identified on the CT in 2 of 3 patients upon careful retrospective review.

Posterior Ligamentous Complex Injuries of the Thoracolumbar Spine: Importance and Surgical Implications

The soft tissues surrounding the spine play a primordial role in its stability, the most important of which are located posteriorly and are deemed the posterior ligamentous complex (PLC). Injuries to the PLC in the setting of thoracolumbar trauma are often dreaded and little attention has been given to them in the management protocols of thoracolumbar trauma. This review aims to summarize and contextualize current concepts in PLC injuries of the thoracolumbar spine with the aim to provide a clear guide for clinical management. Injuries to the PLC may be suspected on the clinical exam but are often missed, leading to serious complications, including instability and neurological compromise. The diagnosis is often made indirectly by spinal radiographs and CT-scanning or by direct visualization of soft tissues via magnetic resonance imaging. The latter remains the standard imaging modality and is mandatory for patients with a high suspicion of PLC injury. PLC injuries are associated with vertebral fractures and follow a progressive pattern of severity, depending on the mechanism of injury and extent of trauma. Surgical management is warranted, as PLC damage renders the spine unstable. Although fusion was once the standard of care and remains applicable for certain patients, recent endeavors of temporary spinal fixation without fusion are increasingly gaining traction in patients with PLC injuries. In conclusion, PLC injuries are challenging as they are often missed, poorly understood, and are not easily managed. Proper diagnosis and management are crucial to avoid long-standing complications such as spinal instability. Considering the paucity of available data on such an important topic in thoracolumbar trauma, this review article aims to contextualize current concepts in PLC injuries in order to demystify this sparsely covered subject.

Development and validation of a simplified thoracolumbar spine fracture classification system

STUDY DESIGN

Development and validation of fracture classification system.

OBJECTIVE

To develop and validate a Simplified Classification System (SCS) for Thoraco-Lumbar (TL) fractures (SCS - TL fractures).

SETTING

Tertiary Spinal Injuries Centre, New Delhi, India METHODS: Based on the International Spinal Cord Society Spine Trauma Study Group (ISCoS STSG, n = 23) experts' clinical consensus conducted by the senior author and on his own experience, the Denis classification for TL fractures was modified to develop a SCS-TL fractures that could guide the management. After Face and Content validation, Construct validation was done in two stages. First stage analyzed if management of 30 cases of TL fractures, as suggested by the SCS - TL fractures and ISCoS STSG (n = 9) as well as other (n = 5) experts, matched. Second stage was a one year prospective study analyzing if the management suggested matched the management actually carried out by different spine surgeons (n = 10) working at a single institution.

RESULTS

In the first stage there was 100% agreement for management (conservative or surgical) as proposed by experts and that suggested by the proposed classification for TL fractures whereas for surgical approach there was 88% agreement. In the second stage, there was 100% agreement for the management as well as surgical approach as carried out at our centre and that proposed by the SCS for TL fractures.

CONCLUSIONS

The proposed SCS-TL fractures helps in classifying and in decision making for management of TL fractures. The next phase of validation would involve multicentric reliability studies and prospective application of the SCS- TL fractures.

Diagnostic Value of Various Morphological Features of Horizontal and Vertical Laminar Fractures for Posterior Ligamentous Complex Injury of the Thoracolumbar Spine as Defined by Magnetic Resonance Imaging

OBJECTIVE

To determine diagnostic value of morphological features of horizontal laminar fracture (HLF) and vertical laminar fracture (VLF) for diagnosis of posterior ligamentous complex (PLC) injury.

METHODS

This retrospective review comprised 271 consecutive patients with acute thoracolumbar fractures presenting to a Level 1 trauma center between January 2014 and January 2021. Two reviewers evaluated computed tomography and magnetic resonance imaging. VLFs were subclassified based on length and depth of lamina involved, as follows: type 1, full-length complete; type 2, full-length incomplete; type 3, partial-length complete or incomplete. HLFs were subclassified as follows: bilateral versus unilateral, displaced >2 mm versus nondisplaced, and lamina-only versus laminar and pedicle. We examined the diagnostic accuracy and the univariate and multivariate associations of laminar fracture subtypes with PLC injury as defined by black stripe discontinuity.

RESULTS

Bilateral HLFs, laminar and pedicle fractures, displaced HLFs, and type 1 VLFs yielded a high positive predictive value for PLC injury (95%, 91%, 100%, and 86%, respectively). Type 2 and 3 VLFs did not show significant univariate associations with PLC injury. Bilateral HLFs, laminar and pedicle fractures, and displaced HLFs showed independent associations with PLC injury (adjusted odds ratio = 13.6, 8.4, 6, and 10.3, respectively; P < 0.002). Type 1 VLFs did not show a significant association with PLC (adjusted odds ratio = 10.3; P = 0.06).

CONCLUSIONS

Bilateral HLFs, laminar and pedicle fractures, and displaced HLFs, but not any VLF subtypes, were independently associated with PLC injury. These findings may improve the reliability of PLC assessment by computed tomography.

Isolated multiple lumbar transverse process fractures with spinal instability: an uncommon yet serious association

PURPOSE

Isolated vertebral transverse process fractures of thoracolumbar spine without other vertebral injuries and neurological deficit are generally considered as minor injuries with no concern for associated spinal instability. This report describes a case of multiple lumbar transverse fractures associated with an unexpected yet clinically significant spinal instability.

METHODS

A young male presented with right flank pain following being pushed and trapped against the ground by a reversing truck. The neurological examination was normal, and computed tomography (CT) imaging revealed multiple fractures at right transverse processes from L1 to L5, a single left-sided transverse process fracture at L2 and subtle facet joint distraction without other spinal lesions or visceral injuries. The injury was initially deemed as stable requiring symptomatic treatment and in-patient observation. However, discharge upright X-rays taken in a brace showed marked subluxation of L2/L3 and L3/L4 levels.

RESULTS

Magnetic resonance imaging revealed significant discoligamentous injuries involving anterior and posterior longitudinal ligaments, annulus fibrosus as well as posterior ligamentous complex. The patient underwent posterior spinal instrumentation and fusion of L1 to L5.

CONCLUSIONS

This is the first case description of association of multisegmental lumbar transverse process fractures with notoriously unstable injuries of the major soft-tissue stabilizers of the spine presenting subtle changes on CT images. When a seemingly benign spinal injury is caused by high-energy trauma, careful scrutiny for associated instability is needed. In this case, the standing in-brace X-ray was able to avoid a misdiagnosis and potentially unfavourable outcome.

Coronal Three-Dimensional Magnetic Resonance Imaging for Improving Diagnostic Accuracy for Posterior Ligamentous Complex Disruption In a Goat Spine Injury Model

Objective

The purpose of this study was to investigate whether three-dimensional (3D) magnetic resonance imaging could improve diagnostic accuracy for suspected posterior ligamentous complex (PLC) disruption.

Materials and Methods

We used 20 freshly harvested goat spine samples with 60 segments and intact surrounding soft tissue. The animals were aged 1–1.5 years and consisted of 8 males and 12 females, which were sexually mature but had not reached adult weights. We created a paraspinal contusion model by percutaneously injecting 10 mL saline into each side of the interspinous ligament (ISL). All segments underwent T2-weighted sagittal and coronal short inversion time inversion recovery (STIR) scans as well as coronal and sagittal 3D proton density-weighted spectrally selective inversion recovery (3D-PDW-SPIR) scans acquired at 1.5T. Following scanning, some ISLs were cut and then the segments were re-scanned using the same magnetic resonance (MR) techniques. Two radiologists independently assessed the MR images, and the reliability of ISL tear interpretation was assessed using the kappa coefficient. The chi-square test was used to compare the diagnostic accuracy of images obtained using the different MR techniques.

Results

The interobserver reliability for detecting ISL disruption was high for all imaging techniques (0.776–0.949). The sensitivity, specificity, and diagnostic accuracy of the coronal 3D-PDW-SPIR technique for detecting ISL tears were 100, 96.9, and 97.9%, respectively, which were significantly higher than those of the sagittal STIR (p = 0.000), coronal STIR (p = 0.000), and sagittal 3D-PDW-SPIR (p = 0.001) techniques.

Conclusion

Compared to other MR methods, coronal 3D-PDW-SPIR provides a more accurate diagnosis of ISL disruption. Adding coronal 3D-PDW-SPIR to a routine MR protocol may help to identify PLC disruptions in cases with nearby contusion.

The impact of urgent intervention on the neurologic recovery in patients with thoracolumbar fractures

Background

We carried out an observational longitudinal retrospective study between 2000 and 2009 in 28 patients who underwent surgery for unstable vertebral fractures with neurologic deficits.

Methods

For the statistical analysis, we used the Chi²-test to compare proportions in independent groups and the exact Fisher test and the Wilcoxon test for repeated measures, and we compared the mean values using the Mann-Whitney U test at a significance level of P<0.05. Timing to surgical intervention (urgent ≤8 vs. >8 h), and neurologic status using the American Spinal Injury Association (ASIA) Impairment Scale at baseline and at the end of follow-up were assessed. We tested the ASIA score improvement at the end of follow-up using multiple regression analysis, adjusted by variables such as ISS, timing of intervention, location, approach and type of fracture.

Results

Twenty-eight patients were included in the analysis. Of the total, 11 (39.2%) underwent surgery urgently (≤8 h) and 17 (60.8%) in >8 h. The mean difference in the neurologic improvement in all patients was 0.97 (95% CI, 0.51-1.42) and was statistically significant (P=0.001). The mean difference in the neurologic improvement in patients with incomplete lesions was 1.59 (95% CI, 1.01-2.17, P=0.001). In these patients, the mean improvement for those intervened in less than 8 h was 1.73 compared to those operated on after more than 8 h (mean improve 0.47) with a difference statistically significant (P=0.007).

Conclusions

Urgent surgery was associated with neurologic improvement in patients with spinal cord injury (SCI). This improvement was mainly observed in patients with an incomplete lesion.

Stepwise resection of the posterior ligamentous complex for stability of a thoracolumbar compression fracture: An in vitro biomechanical investigation

To quantify the mechanical contribution of posterior ligamentous structures to the stability of thoracolumbar compression fractures.Twelve fresh human T11-L3 spinal specimens were harvested in this study. The 1/3 L1 vertebral body was resected in a wedged shape. After the preinjury had been created, the specimens were subjected to flexion-compression to create a fracture model. Resection of the ligaments was performed in a sequential manner from the bilateral facet capsule ligament (FCL), interspinous ligament, and supraspinous ligament (SSL) to the ligamentum flavum at the T12-L1 level. Then, for the intact specimen, fracture model, and ligament disruption steps, the range of motion (ROM) and neutral zone (NZ) of T12-L1 and L1-L2 were collected for each simulated movement.Sequential transection of the posterior ligamentous complex (PLC), ROM, and NZ were increased in all movements at the T12-L1 segment. In the flexion-extension (FE), the ROM and NZ demonstrated significant increases after the fracture model and resection of SSL and LF. In lateral bending (LB), the ROM increased after the fracture and removal of the LF, while the NZ showed a slight increase. In axial rotation, the fracture model and removal of the LF resulted in a significant increase in the ROM, and the NZ showed a slight change after step reduction. For the L1-L2 segment, resection of the FCL led to an increased ROM in LB.With rupture of SSL or LF, the stability of the segment decreased significantly compared with the intact and fracture model, particularly in FE motion, the function of the PLC was considered to be incompetent.

Survey of French spine surgeons reveals significant variability in spine trauma practices in 2013

BACKGROUND

In France, attempts to define common ground during spine surgery meetings have revealed significant variability in clinical practices across different schools of surgery and the two specialities involved in spine surgery, namely, neurosurgery and orthopaedic surgery.

OBJECTIVES

To objectively characterise this variability by performing a survey based on a fictitious spine trauma case. Our working hypothesis was that significant variability existed in trauma practices and that this variability was related to a lack of strong scientific evidence in spine trauma care.

METHODS

We performed a cross-sectional survey based on a clinical vignette describing a 31-year-old male with an L1 burst fracture and neurologic symptoms (numbness). Surgeons received the vignette and a 14-item questionnaire on the management of this patient. For each question, surgeons had to choose among five possible answers. Differences in answers across surgeons were assessed using the Index of Qualitative Variability (IQV), in which 0 indicates no variability and 1 maximal variability. Surgeons also received a questionnaire about their demographics and surgical experience.

RESULTS

Of 405 invited spine surgeons, 200 responded to the survey. Five questions had an IQV greater than 0.9, seven an IQV between 0.5 and 0.9, and two an IQV lower than 0.5. Variability was greatest about the need for MRI (IQV=0.93), degree of urgency (IQV=0.93), need for fusion (IQV=0.92), need for post-operative bracing (IQV=0.91), and routine removal of instrumentation (IQV=0.94). Variability was lowest for questions about the need for surgery (IQV=0.42) and use of the posterior approach (IQV=0.36). Answers were influenced by surgeon specialty, age, experience level, and type of centre.

CONCLUSION

Clinical practice regarding spine trauma varies widely in France. Little published evidence is available on which to base recommendations that would diminish this variability.

An independent interobserver reliability and intraobserver reproducibility evaluation of the new AOSpine Thoracolumbar Spine Injury Classification System

STUDY DESIGN

Agreement study.

OBJECTIVE

To perform an independent interobserver and intraobserver agreement evaluation of the new AOSpine Thoracolumbar Spine Injury Classification System.

SUMMARY OF BACKGROUND DATA

The new AOSpine Thoracolumbar Spine Injury Classification System was recently published. It showed substantial reliability and reproducibility among the surgeons who developed it; however, an independent evaluation has not been performed.

METHODS

Anteroposterior and lateral radiographs, and computed tomographic scans of 70 patients with acute traumatic thoracolumbar injuries were selected and classified using the morphological grading of the new AOSpine Thoracolumbar Spine Injury Classification System by 6 evaluators (3 spine surgeons and 3 orthopedic surgery residents). After a 6-week interval, the 70 cases were presented in a random sequence to the same evaluators for repeat evaluation. The Kappa coefficient (κ) was used to determine the interobserver and intraobserver agreement.

RESULTS

The interobserver reliability was substantial when considering the fracture type (A, B, or C), with a κ= 0.62 (0.57-0.66). The interobserver agreement when considering the subtypes was moderate; κ= 0.55 (0.52-0.57). The intraobserver reproducibility was also substantial, with 85.95% full intraobserver reproducibility considering the fracture type, with κ= 0.77 (0.72-0.83), and was also substantial when considering subtypes with 75.71% full agreement and κ= 0.71 (0.67-0.76). No significant differences were observed between spine surgeons and orthopedic residents in the overall interobserver reliability and intraobserver reproducibility, or in the inter- and intraobserver agreement of specific A, B, or C types of injuries.

CONCLUSION

This classification allows adequate agreement among different observers and by the same observer on separate occasions. Future prospective studies should evaluate whether this classification improves clinical decision making.

Spinal cord injury after blunt cervical spine trauma: correlation of soft-tissue damage and extension of lesion

BACKGROUND AND PURPOSE

In patients with spinal cord injury after blunt trauma, several studies have observed a correlation between neurologic impairment and radiologic findings. Few studies have been performed to correlate spinal cord injury with ligamentous injury. The purpose of this study was to retrospectively evaluate whether ligamentous injury or disk disruption after spinal cord injury correlates with lesion length.

MATERIALS AND METHODS

We retrospectively reviewed 108 patients diagnosed with traumatic spinal cord injury after cervical trauma between 1990-2011. Plain films, CT, and MR imaging were performed on patients and then reviewed for this study. MR imaging was performed within 96 hours after cervical trauma for all patients. Data regarding ligamentous injury, disk injury, and the extent of the spinal cord injury were collected from an adequate number of MR images. We evaluated anterior longitudinal ligaments, posterior longitudinal ligaments, and the ligamentum flavum. Length of lesion, disk disruption, and ligamentous injury association, as well as the extent of the spinal cord injury were statistically assessed by means of univariate analysis, with the use of nonparametric tests and multivariate analysis along with linear regression.

RESULTS

There were significant differences in lesion length on T2-weighted images for anterior longitudinal ligaments, posterior longitudinal ligaments, and ligamentum flavum in the univariate analysis; however, when this was adjusted by age, level of injury, sex, and disruption of the soft tissue evaluated (disk, anterior longitudinal ligaments, posterior longitudinal ligaments, and ligamentum flavum) in a multivariable analysis, only ligamentum flavum showed a statistically significant association with lesion length. Furthermore, the number of ligaments affected had a positive correlation with the extension of the lesion.

CONCLUSIONS

In cervical spine trauma, a specific pattern of ligamentous injury correlates with the length of the spinal cord lesion in MR imaging studies. Ligamentous injury detected by MR imaging is not a dynamic finding; thus it proved to be useful in predicting neurologic outcome in patients for whom the MR imaging examination was delayed.

Prospective analysis of magnetic resonance imaging accuracy in diagnosing traumatic injuries of the posterior ligamentous complex of the thoracolumbar spine

STUDY DESIGN

Prospective cohort study.

OBJECTIVE

To study magnetic resonance imaging (MRI) accuracy in diagnosing posterior ligamentous complex (PLC) damage, when applying the new dichotomic instability criteria in a prospective cohort of patients with vertebral fracture.

SUMMARY OF BACKGROUND DATA

Recent studies dispute MRI accuracy to diagnose PLC injuries. They analyze the complex based on 3 categories (intact/indeterminate/rupture), including the indeterminate in the ruptured group (measurement bias) in the accuracy analysis. Moreover, fractures with conservative treatment (selection bias) are not included. Both facts reduce the specificity. A recent study has proposed new criteria where posterior instability is determined with supraspinous ligament (SSL) rupture.

METHODS

Prospective study of patients with acute thoracolumbar fracture, using radiography and MRI (FS-T2-w/short-tau inversion-recovery sequences). 1. The integrity (ruptured/unruptured) of each isolated component of the PLC (facet capsules, interspinous ligament, SSL, and ligamentum flavum) was assessed via MRI and surgical findings. 2. PLC integrity as a whole was assessed, adopting the new dichotomic stability criteria from previous studies. In the MR images, PLC is considered ruptured when the SSL is found discontinued, and intact when not (this excludes the "indeterminate" category). In surgically treated fractures, PLC stability as a whole was assessed dynamically (ruptured/unruptured). In conservative fractures, PLC stability was assessed according to change in vertebral kyphosis measured with the local kyphotic angle at 2-year follow-up (ruptured if difference is > 5°/unruptured if difference is < 5°).3. Comparative analysis among findings provided MRI accuracy in diagnosing PLC damage.

RESULTS

Fifty-eight vertebral fractures were studied (38 surgical, 20 conservative), of which 50% were in males; average age, 40.4 years. MRI sensitivity for injury diagnosis of each isolated PLC component varied between 92.3% (interspinous ligament) and 100% (ligamentum flavum). Specificity varied between 52% (facet capsules) and 100% (SSL). PLC integrity sensitivity and specificity as a whole were 91% and 100%, respectively.

CONCLUSION

Adopting the new stability criteria, MRI accuracy in PLC injury diagnosis increases. Specificity is increased (true positives) both in isolated component analysis and PLC as a whole.

Vertebral body stenting versus kyphoplasty for the treatment of osteoporotic vertebral compression fractures: a randomized trial

BACKGROUND

In the treatment of vertebral compression fractures, vertebral body stenting with an expandable scaffold inserted before application of the bone cement was developed to impede secondary loss of vertebral height encountered in patients treated with balloon kyphoplasty. The purpose of this study was to clarify whether there are relevant differences between balloon kyphoplasty and vertebral body stenting with regard to perioperative and postoperative findings.

METHODS

In a two-armed randomized controlled trial, patients with a total of 100 fresh osteoporotic vertebral compression fractures were treated with either balloon kyphoplasty or vertebral body stenting. The primary outcome was the post-interventional change in the kyphotic angle on radiographs. The secondary outcomes were the maximum pressure of the balloon tamp during inflation, radiation exposure time, perioperative complications, and cement leakage.

RESULTS

The mean reduction (and standard deviation) of kyphosis (the kyphotic correction angle) was 4.5° ± 3.6° after balloon kyphoplasty and 4.7° ± 4.2° after vertebral body stenting (p = 0.972). The mean pressures were 24 ± 5 bar (348 ± 72 pounds per square inch [psi]) during vertebral body stenting and 16 ± 6 bar (233 ± 81 psi) during balloon kyphoplasty (p = 0.014). There were no significant differences in radiation exposure time.None of the patients underwent revision surgery, and postoperative neurologic sequelae were not observed. Cement leakage occurred at twenty-five of the 100 vertebral levels without significant differences between the two intervention arms (p = 0.230). Intraoperative material-related complications were observed at one of the fifty vertebral levels in the balloon kyphoplasty group and at nine of the fifty levels in the vertebral body stenting group.

CONCLUSIONS

No beneficial effect of vertebral body stenting over balloon kyphoplasty was found among patients with painful osteoporotic vertebral fractures with regard to kyphotic correction, cement leakage, radiation exposure time, or neurologic sequelae. Vertebral body stenting was associated with significantly higher pressures during balloon inflation and more material-related complications.

Surgical treatment of lumbar spinal stenosis with microdecompression and interspinous distraction device insertion. A case series

BACKGROUND

Interspinous distraction devices (IPDD) are indicated as stand-alone devices for the treatment of spinal stenosis. The purpose of this study is to evaluate the results of patients undergoing surgery for spinal stenosis with a combination of unilateral microdecompression and interspinous distraction device insertion.

METHODS

This is a prospective clinical and radiological study of minimum 2 years follow-up. Twenty-two patients (average age 64.5 years) with low-back pain and unilateral sciatica underwent decompressive surgery for lumbar spinal stenosis. Visual Analogue Scale, Oswestry Disability Index and walking capacity plus radiologic measurements of posterior disc height of the involved level and lumbar lordosis Cobb angle were documented both preoperatively and postoperatively. One-sided posterior subarticular and foraminal decompression was conducted followed by dynamic stabilization of the diseased level with an IPDD (X-STOP).

RESULTS

The average follow-up time was 27.4 months. Visual Analogue Scale and Oswestry Disability Index improved statistically significantly (p < 0.001) in the last follow-up exam. Also, the walking distance increased in all patients but two. Posterior intervertebral disc height of the diseased level widened average 1.8 mm in the postoperative radiograph compared to the preoperative. No major complication, including implant failure or spinous process breakage, has been observed.

CONCLUSIONS

The described surgical technique using unilateral microdecompression and IPDD insertion is a clinically effective and radiologically viable treatment method for symptoms of spinal stenosis resistant to non-operative treatment.

MRI study of post-traumatic incompetence of posterior ligamentous complex: importance of the supraspinous ligament. Prospective study of 74 traumatic fractures

PURPOSE

Posterior ligamentous complex (PLC) components have an orderly sequence of rupture. However, it is still unclear how many structures have to be damaged to consider it disrupted. We aim to establish imaging criteria, which can define the complex as competent or incompetent.

METHODS

Prospective study of 74 consecutive vertebral acute traumatic fractures, using X-rays and MRI scan (FS-T2-w/STIR sequences). We analyzed the association between MRI signal (intact, edema, disruption) of each PLC component-facet capsules (FC), interspinous ligaments (ISL), supraspinous ligaments (SSL) and ligamentum flavum (LF)-and the variables: AO/TLICS classification, treatment, surgical findings, interspinous diastasis index (IDI), local kyphosis (LVK) and ISS (TLICS) score. χ2 test and U Mann-Whitney were used for statistics.

RESULTS

MR images of ISL edema correlated surgically with intact ligaments or laxity, and were associated with 87.5% of facet distraction, LVK: 11.6º, IDI: 1.2. Images of ISL, SSL or LF disruptions showed in all cases ruptures under surgical examination. Images of SSL disruption associated with LVK: 14.5º, IDI: 1.8. Images of ISL disruption associated with SSL/LF rupture, LVK: 16º, and IDI: 2; while LF disruption showed LVK: 18º, IDI: 1.9. When comparing "competent PLC" (images of facet distraction and ISL edema) with "incompetent PLC" (images of SSL disruption ± ISL or LF disruption) the latest showed more severe scores in every variable (p < 0.001), except neurologic status.

CONCLUSION

Following PLC rupture sequence, ISL edema with facet distraction seems not to be enough to define a posterior tension band incompetence. It is the further step of SSL rupture what gives the key to PLC incompetence.