Can lacerations of the thoraco-lumbar dura be predicted on the basis of radiological patterns of the spinal fractures?

How does vertical laminar fracture impact the decision-making in thoracolumbar fractures? A systematic scoping review and meta-analysis

OBJECTIVE

Although vertical laminar fracture (VLF) is generally considered a severity marker for thoracolumbar fractures (TLFs), its exact role in decision-making has never been established. This scoping review aims to synthesize the research on VLF's role in the decision-making of TLFs.

METHODS

A systematic review was conducted following PRISMA guidelines. We searched PubMed, Scopus, and Web of Science from inception to  June 11, 2023, for studies examining the association of VLF in thoracolumbar fractures with dural lacerations, neurological deficits, radiographic parameters, or treatment outcomes. Additionally, experimental studies that analyze the biomechanics of burst fractures with VLF were included. The studies extracted key findings, objectives, and patient population. A meta-analysis was performed for the association of VLF with dural laceration and neurological deficit, and ORs were pooled with a 95% confidence interval (CI).

RESULTS

Twenty-eight studies were included in this systematic review, encompassing 2021 patients, and twelve were included in the meta-analysis. According to the main subject of the study, the association of VLF with a dural laceration (n = 14), neurological deficit (n = 4), radiographic parameters (n = 3), thoracolumbar fracture classification (n = 2), and treatment outcome (n = 2). Seven studies with a total of 1010 patients reported a significant association between VLF and neurological deficit (OR = 7.35, 95% CI [3.97, 14.25]; P < 0.001). The pooled OR estimates for VLF predicting dural lacerations were 7.75, 95% CI [2.41, 24.87]; P < 0.001).

CONCLUSION

VLF may have several important diagnostic and therapeutic implications in managing TLFs. VLF may help to distinguish AO type A3 from A4 fractures. VLF may help to predict preoperatively the occurrence of dural laceration, thereby choosing the optimal surgical strategy. Clinical and biomechanical data suggest VLF may be a valuable modifier to guide the decision-making in burst fractures; however, more studies are needed to confirm its prognostic importance regarding treatment outcomes.

Case series of posterior instrumentation for repair of burst lumbar vertebral body fractures with entrapped neural elements

Background

Burst fractures of the lumbar vertebrae and laminar fractures associated with dural tears and entrapment of neural elements have been reported in the past as a relatively rare occurrence. To the best of our knowledge, there is no consensus on the approach to repairing these types of fractures. The objective of this study is to describe a method of repair for traumatic burst fractures of the lumbar spine and vertical laminar fractures associated with entrapped neural elements.

Methods

Seventeen patients with lumbar burst fractures were treated from June 2015 through April 2017. Dural tear was detected in all cases included in this study (confirmed intra-operatively). All other burst fractures were excluded. In all cases, unilateral posterior fixation was performed with no distraction initially. The spinal canal was then decompressed; and the entrapped neural elements released. Formal distraction was performed after canal decompression to allow for ligamentotaxis, followed by reduction of the retropulsed fractured segments back into the vertebral body.

Results

Using this method we achieved satisfactory results in that none of the patients had further deterioration of neurological deficit and the fixation allowed for early mobilization. Continued improvement was seen at the time of follow up for each of the studied patients with improved neurology, pain and no CSF leak.

Conclusions

Our institution has demonstrated successful use of a posterior instrumentation, spinal canal decompression, release of entrapped nerve roots, and reduction of the retropulsed segment, in patients with traumatic burst fracture of the lumbar vertebrae complicated by entrapped neural elements.

Magnetic resonance imaging features of dogs with incomplete recovery after acute, severe spinal cord injury

STUDY DESIGN

Retrospective case series.

OBJECTIVES

Describe the magnetic resonance imaging (MRI) features of dogs chronically impaired after severe spinal cord injury (SCI) and investigate associations between imaging variables and residual motor function.

SETTING

United States of America.

METHODS

Thoracolumbar MRI from dogs with incomplete recovery months to years after clinically complete (paralysis with loss of pain perception) thoracolumbar SCI were reviewed. Lesion features were described and quantified. Gait was quantified using an ordinal, open field scale (OFS). Associations between imaging features and gait scores, duration of injury (DOI), or SCI treatment were determined.

RESULTS

Thirty-five dogs were included. Median OFS was 2 (0-6), median DOI was 13 months (3-83), and intervertebral disk herniation was the most common diagnosis (n = 27). Myelomalacia was the most common qualitative feature followed by cystic change; syringomyelia and fibrosis were uncommon. Lesion length corrected to L2 length (LL:L2) was variable (median LL:L2 = 3.5 (1.34-11.54)). Twenty-nine dogs had 100% maximum cross-sectional spinal cord compromise (MSCC) at the lesion epicenter and the length of 100% compromised area varied widely (median length 100% MSCC:L2 = 1.29 (0.39-7.64)). Length 100% MSCC:L2 was associated with OFS (p = 0.012). OFS was not associated with any qualitative features. DOI or treatment type were not associated with imaging features or lesion quantification.

CONCLUSIONS

Lesion characteristics on MRI in dogs with incomplete recovery after severe SCI were established. Length of 100% MSCC was associated with hind limb motor function. Findings demonstrate a spectrum of injury severity on MRI among severely affected dogs, which is related to functional status.

Behavior of Injured Lamina in Lumbar Burst Fractures during Reduction Maneuvers: A Biomechanical Study

STUDY DESIGN

An experimental biomechanical study.

PURPOSE

This study aims to investigate the behavior of a lamina injury in lumbar burst fractures during reduction maneuvers.

OVERVIEW OF LITERATURE

Lumbar burst fractures are frequently accompanied by a lamina fracture. Many researchers concluded that any reduction maneuver will close the fractured lamina edges and possibly crush the entrapped neural elements. This conclusion did not rely on solid biomechanical trials and was based primarily on clinical experience.

METHODS

Eighteen fresh-frozen lamb spines were randomly divided into three groups. Using the preinjury and the dropped-mass technique, a burst fracture model was developed. A central laminectomy of 5 mm of the L3 lumbar spine was created to mimic a complete type of lamina fracture. To measure the movement of the fractured laminar edges, two holes were drilled on both sides of the upper and lower regions of the lamina to allow for optic marker placement. A single specific spine movement was applied to each group: traction, flexion, and extension. Gap changes were measured by camera extensometers.

RESULTS

After traction, the average values of the upper and lower aspects of the lamina interval showed narrowing of 1.65±0.82 mm and 1.97±1.14 mm, respectively. No statistical significance was detected between the two aspects. The upper and lower regions of the lamina gap behaved differently during extension. At 10°, 20°, and 30°, the upper part of the lamina interval was widened by an average of 0.016±0.024, 0.29±0.32, and 1.73±1.45 mm, respectively, whereas the lower part was narrowed by an average of 0.023±0.012, 0.47±0.038, and 1.94±1.46 mm, respectively.

CONCLUSIONS

Neural element crushing may take place, particularly at the lower aspect of the fractured lamina gap during extension and throughout the whole lamina gap during traction. The lamina gap widens during flexion. Reduction maneuvers should be attempted after exploring the fractured lamina to prevent further neurological compromise.

Predictable imaging signs of cauda equina entrapment in thoracolumbar and lumbar burst fractures with greenstick lamina fractures

STUDY DESIGN

A retrospective study.

PURPOSE

The aim of present study was to investigate imaging findings suggestive of cauda equina entrapment in thoracolumbar and lumbar burst fractures.

OVERVIEW OF LITERATURE

Burst fractures with cauda equina entrapment can cause neurologic deterioration during surgery. However, dural tears and cauda equina entrapment are very difficult to diagnose clinically or radiographically before surgery.

METHODS

Twenty-three patients who underwent spinal surgery for thoracolumbar or lumbar burst fractures were enrolled in this study. In magnetic resonance imaging T2-weighted images of the transverse plane, we defined cauda equina notch sign (CENS) as a v-shaped image that entrapped cauda equina gathers between lamina fractures. We evaluated the fractured spine by using CENS and lamina fractures and the rate of available space for the spinal canal at the narrowest portion of the burst fracture level. We classified patients into entrapment group or non-entrapment group, based on whether cauda equina entrapment existed.

RESULTS

Lamina fractures were detected in 18 (78.3%) and CENS were detected in 6 (26.1%) of 23 burst-fracture patients. Cauda equina entrapment existed in all the patients with CENS. In addition, the rate of available space for the spinal canal increased according to logistic regression. The size of the retropulsed fragment in the spinal canal was the most reliable of all the factors, suggesting cauda equina entrapment.

CONCLUSIONS

CENS was the most predictable sign of cauda equina entrapment associated with burst fractures.

Traumatic dural tears: what do we know and are they a problem?

BACKGROUND CONTEXT

Iatrogenic dural tears are common complications encountered in spine surgery with known ramifications. There is little information, however, with respect to the implications and complications of traumatic dural tears.

PURPOSE

To describe the demographics and characteristics of traumatically acquired dural tears and evaluate the complication rate associated with traumatic dural tears in patients who have undergone surgical treatment for spine injuries.

STUDY DESIGN

Retrospective review of a single Level I trauma center to identify patients with traumatic dural tears between January 1, 2003 and December 31, 2009.

PATIENT SAMPLE

The sample comprises 187 patients with traumatic dural tears identified from 1,615 patients who underwent operative management of their traumatic injury.

OUTCOME MEASURES

The outcome measures consisted of a description of the location and nature of dural tears and associated fracture patterns and neurologic status as well as an assessment of complications attributable to the traumatic dural tear.

METHODS

No funding was received or used in this study. In total, 1,615 operatively managed spine injuries over a 7-year period were reviewed to identify 187 patients with traumatic dural tears. Operative reports were reviewed to assess location and description of injury as well as type of repair, if done. Associated spinal cord injuries as well as fracture level, patterns, and complications were recorded. Postoperative records were assessed focusing on complications related to the traumatic dural tears.

RESULTS

Traumatic dural tears were identified in 9.1% (67/739) of cervical, 9.9% (45/452) of thoracic, and 17.6% (75/424) of lumbosacral spine fractures. Among the patients, 82.3% (154/187) had a formal dural repair. Fracture patterns included burst (AO Type A3) 26.2% (49/187), flexion distraction (AO Type B) 16% (30/187), and fracture dislocations (AO Type C) 36.4% (68/187). A complete neurologic injury was noted in 48.7% (91/187) of the patient population, whereas no neurologic injury was noted in 17.1% (32/187). Two patients (1%) developed a persistent cerebral spinal fluid leak that necessitated an irrigation and debridement with exploration and closure of the cerebral spinal fluid tear. Two patients (1%) developed a pseudomeningocele; one required a return to the operating room for irrigation and debridement, and the other suspected of having developed meningitis was treated with intravenous antibiotics. Among the patients, 2.1% (4/187) were noted to have a complication directly related to a traumatic dural tear.

CONCLUSIONS

Traumatic dural tears occurred in 11.6% of patients with operatively managed traumatic spine injuries at a regional Level 1 trauma center. In total, 83% had a neurologic injury and 49% had complete spinal cord injuries. Patients with traumatically induced dural tears have a low likelihood of developing a complication attributable to the dural tear.

Predictable factors for dural tears in lumbar burst fractures with vertical laminar fractures

OBJECTIVE

The purpose of the present study was to determine the incidence of dural tears and predictable factors suggesting dural tears in patients who had lumbar burst fractures with vertical laminar fractures.

METHODS

A retrospective review was done on thirty-one patients who underwent operative treatment for lumbar burst fractures with vertical laminar fractures between January 2003 and December 2008. All patients were divided into two groups according to existence of dural tears, which were surgically confirmed; 21 patients with dural tears and 10 patients without dural tears. Clinical and radiographic findings were analyzed for their association with dural tears.

RESULTS

Among a total of 31 patients, dural tears were detected in 21 (67%) patients. A preoperative neurological deficits and mean separation distances of the edges in laminar fractures were found to be the reliable factors of dural tears (p=0.001 and 0.002, respectively). Decreased ratio of the central canal diameter and interpedicular distance were also the reliable factors suggesting dural tears (p=0.006 and 0.015, respectively). However, dural tears showed no significant association with age, sex, level of injury, absence of a posterior fat pad signal, the angle of retropulsed segment, or site of laminar fracture.

CONCLUSION

Our study of lumbar burst fracture combined laminar fracture revealed that dural tears should be ruled out in cases of a preoperative neurological deficits, wide separation of the laminar fracture, severe canal encroachment, and wider interpedicular distance.

Bacterial meningitis after traumatic thoracic fracture-dislocation: two case reports and review of the literature

Bacterial meningitis occurs rarely in the setting of traumatic spinal injury. Bacterial meningitis after spinal surgery for traumatic thoracic fracture-dislocation injuries has not been reported. We report on two cases of bacterial meningitis in two pediatric patients undergoing posterior segmental instrumentation with pedicle screws after thoracic fracture-dislocation injuries with associated traumatic dural laceration and complete spinal cord transection. Both patients were treated and recovered. Early recognition of bacterial meningitis after traumatic spinal injury enables appropriate and timely treatment to be instituted and can yield a favorable outcome.

Dural tears in spinal burst fractures: predictable MR imaging findings

BACKGROUND AND PURPOSE

The diagnosis of traumatic spinal dural tears is difficult to establish. The purpose of this study was to determine the reliable MR imaging findings suggesting dural tears in spinal burst fractures.

MATERIALS AND METHODS

We retrospectively reviewed spine MR images of 21 patients with dural tears (study group) and 33 patients without dural tears (control group), all of whom had spinal burst fractures. The following MR imaging features were compared between the 2 groups: the interpedicular distance, the angle of the retropulsed segments, the ratio of the central canal diameter, the presence or absence of laminar fractures, the degree of laminar fractures, and the extent of epidural hemorrhage.

RESULTS

The mean values of the grade of the laminar fracture, the interpedicular distance, the ratio of the central canal diameter, the angle of the retropulsed segment, and the extent of epidural hemorrhage in the study and control groups were as follows: 1.77 and 0.86 (P = .034), 28.7 and 26 mm (P = .02), 0.37 and 0.58 (P = .008), 112 degrees and 128 degrees (P = .05), and 2.37 and 1.4 (P = .11), respectively. The ratio of the central canal diameter was the most reliable factor suggesting dural tears compared with other factors.

CONCLUSIONS

Dural tears are likely when there are MR imaging findings of laminar fracture of more than grade 1, the interpedicular distance is >28 mm, the central canal ratio is <0.46, and the acute angle of the retropulsed segment is <135 degrees .

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

STUDY DESIGN

Prospective randomized study. OBJECTIVES.: To compare the results of the combined anterior-posterior surgery (Group A) with posterior "short-segment" transpedicular fixation (SSTF) (Group B) in mid-lumbar burst fractures.

SUMMARY OF BACKGROUND DATA

There are no comparative randomized clinical studies on the outcome following operative treatment of mid-lumbar fractures.

METHODS

Forty consecutive patients with L2-L4 fresh single A3-type/AO burst fractures and load sharing score up to 6 were randomly selected to underwent either combined one-stage anterior stabilization with mesh cage and SSTF (Group A) or solely SSTF with intermediate screws in the fractured vertebra (Group B). Kyphotic Gardner angle, anterior and posterior vertebral body height (PVBHr, AVBHr), spinal canal encroachment (SCE), SF-36, VAS, and Frankel classification were used.

RESULTS

The follow-up observation averaged 46 and 48 months for Group A and B, respectively. Operative time, blood loss, and hospital stay were significant more in Group A. More surgical complications were observed in the Group A. After surgery, VAS was reduced to 4.3 and 3.6 for Group A and Group B, respectively. The SF-36 domains Role physical and Bodily pain improved significantly only in Group B (P = 0.05) and (P = 0.06), respectively. Correction of AVBHr, PVBHr, and spinal canal clearance was similar in both groups. Spinal canal clearance did not differ between the two groups, but it was continuous until the last evaluation in Group B. The final Gardner angle loss of correction averaged 2 degrees and 5 degrees for Group A and Group B, respectively. The posttraumatic Gardner deformity did not significantly improve by SSTF at the final evaluation in the spines of Group B. Gardner angle correlated significantly with SCE in Group B and Group A in all three periods and in the last evaluation, respectively. Frankel grade did not correlate with loss of correction of AVBHr and PVBHr in Group A, while it significantly correlated with loss of PVBHr correction and SCE in the patients of Group B. There was no neurologic deterioration after surgery in any patient. VAS and SF-36 scores did not significantly correlate with the loss of kyphotic angle correction and AVBHr, PVBHr at the final observation in any patient of both groups.

CONCLUSIONS

SSTF offered similar significant short-term correction of posttraumatic deformities associated with mid-lumbar A3-burst fractures, but better clinical results as compared to combined surgery. However, SSTF did not significantly maintain the after surgery achieved correction of local posttraumatic kyphosis at the final evaluation. Thus, SSTF is not recommended for operative stabilization of fractures with this severity.

Importance of greenstick lamina fractures in low lumbar burst fractures

Lumbar burst fractures (L3-L5) represent a small percentage of all spinal fractures. The treatment of fractures involving the lumbar spine has been controversial. Lamina fractures may be complete or of the greenstick type. Dural tears and nerve root entrapment may accompany these lamina fractures. The aim of this retrospective study was to determine the incidence of dural tear in patients who had lumbar burst fractures with greenstick lamina fractures and the importance of these lamina fractures when choosing the optimum treatment. Twenty-six patients with 28 lumbar burst fractures were treated from 1995 through 2002. The average follow-up was 60 months (range 32-110 months). The male to female ratio was 21:5 and the mean age was 37 years (17-64). Dural tear was detected in seven (25%) out of 28 burst fractures. The functional outcome of the entire study group was assessed using the Smiley-Webster Scale. Good to excellent results were obtained in 24 (92%) of 26 patients. Lumbar burst fractures with greenstick lamina fractures occur mostly in the L2-L4 area. In the surgical treatment, any reduction manoeuvre will close the fracture and crush the entrapped neural elements. Therefore, it may be better to explore the greenstick lamina fracture whether there is any neural entrapment or not, before any reduction manoeuvre is attempted.

Dural tears in lumbar burst fractures with greenstick lamina fractures

STUDY DESIGN

This study investigated the incidence, predictions, and treatment principles of greenstick lamina fractures in lumbar burst fractures.

OBJECTIVE

To determine the incidence of dural tears in lumbar burst fracture with greenstick lamina fracture and to find out if any specific clinical and radiographic factors or intraoperative pathologic findings are predictive of dural tears and nerve root entrapment.

SUMMARY OF BACKGROUND DATA

A retrospective review was conducted on 45 patients with 47 lumbar burst fractures treated operatively. Ages ranged from 15 to 70 years (average, 33 years). The duration of follow-up ranged from 32 months to 8 years (average, 52 months).

METHODS

All clinical charts and radiologic data of these patients were reviewed. Age, sex, etiology, and all the radiologic parameters were analyzed for their association with greenstick lamina fracture and dural tear. Student's t test and multiple logistic regression analysis were used for statistical analysis.

RESULTS

Greenstick lamina fracture occurred in 20 (42.5%) of 47 burst fractures. Dural tear was detected in 9 (19%) of 47 burst fractures and was predominantly higher in L3 (6 of 9 burst fractures). According to multiple logistic regression analysis of the data, a 20% increase in the interpedicular distance gives a 79% probability of greenstick lamina fracture. The distance between the edges of greenstick lamina fractures was obviously higher in fractures with dural tear. Neurologic status was completely normal before surgery in three of the patients with dural tear and nerve root entrapment.

CONCLUSIONS

It is not possible to detect dural tear and nerve root entrapment in greenstick lamina fracture before surgery. Therefore, if there is any suspicion of such an occurrence, it should be the rule to begin with posterior approach and use the open book technique to expose the dura safely before any reduction maneuver.