Relationship between fracture-relevant parameters of thoracolumbar burst fractures and the reduction of intra-canal fracture fragment

Posterior Pedicle Screw Fixation With Indirect Decompression Versus Direct Decompression in Treating Thoracolumbar Burst Fracture: A Systematic Review and Meta-Analysis

OBJECTIVE

To compare the safety and efficacy between posterior pedicle screw fixation with direct versus indirect decompression in treating patients with thoracolumbar burst fracture.

METHODS

This study was conducted on the basis of PRISMA statement. We systematically searched the PubMed and Embase databases up to July 3, 2023. Relevant studies comparing indirect decompression and direct decompression were recruited. Weighted mean differences (WMDs), odds ratios (ORs) and 95% confidence intervals (CIs) were analyzed for continuous and dichotomous data, respectively. P < 0.05 was considered statistically significant.

RESULTS

The operation time (WMD: -37.14, 95% CI: [-42.64, 31.64], P < 0.00001, I2 = 0%) and intraoperative blood loss (WMD: -316.82, 95% CI: [-469.80, -163.85], P < 0.0001, I2 = 99%) of indirect decompression group were significantly lower. Percentage of anterior vertebral body height (WMD: 3.98, 95% CI: [2.36, 5.60], P < 0.00001, I2 = 32%) and encroachment rate of the spinal canal (WMD: 1.48, 95% CI: [0.56, 2.40], P = 0.002, I2 = 35%) of indirect decompression group were significantly higher. No statistical difference was identified in grades of neurologic recovery and Cobb angle.

CONCLUSIONS

Posterior pedicle screw fixation with indirect decompression was safe and effective for thoracolumbar burst fracture with or without neurologic deficits when posterior longitudinal ligament was intact.

Surgical timing prevails as the main factor over morphologic characteristics in the reduction by ligamentotaxis of thoracolumbar burst fractures

BACKGROUND

thoracolumbar burst fractures are associated with spinal canal occupation. The indirect decompression of the spinal canal and reduction of the fragment can be achieved with the distraction of the middle column and ligamentotaxis. Nevertheless, the factors that influence the effectiveness of this procedure and its temporality are controversial.

METHODS

The aim of this observational, cross-sectional study was to evaluate the effectiveness of indirect reduction by ligamentotaxis in thoracolumbar burst fractures according to the fracture's radiologic characteristics and the procedure's temporality. Patients diagnosed with a thoracolumbar burst fracture between 2010 and 2021 were submitted to indirect reduction by distraction and ligamentotaxis. A retrospective analysis of radiologic characteristics and temporality of the procedure was performed with an independent sample t-test or Pearson's correlation coefficient, as required.

RESULTS

A total of 58 patients were included in the analysis. Postoperatively, ligamentotaxis significantly improved all radiologic parameters (canal occupation, endplates distance, and vertebra height). Still, none of the radiological characteristics of the fracture (width, height, position, sagittal angle) were associated with the postoperative change in canal occupation. The endplates distance and the temporality of ligamentotaxis significantly predicted the reduction of the fracture.

CONCLUSION

Fragment reduction effectiveness is more significant when performed as early as possible and adequate distraction is achieved using the internal fixator system. The radiologic characteristics of the fractured fragment do not determine its reduction capacity.

The anatomic study and surgical technique for canal decompression with "pedicle-plasty" strategy in lumbar burst fractures with pedicle rupture

In the treatment of lumbar burst fractures with nerve injury, fusion is often required to rebuild spinal stability, but it can lead to the loss of motor units and increase the occurrence of adjacent segment diseases. Thus, a novel approach of lumbar canal decompression with "pedicle-plasty" strategy (DDP) was needed in clincal treatment. Firstly, image measurement analysis, the images of 60 patients with lumbar spine CT examinations were selected to measure osteotomy angle (OA), distance from the intersection of osteotomy plane and skin to the posterior midline (DM),transverse length of the osteotomy plane (TLOP), and sagittal diameter of the outer edge of superior articular process (SD). Secondary, cadaver study, distance between the intermuscular space and midline (DMSM), anterior and posterior diameters of the decompression (APDD), and lateral traction distance of the lumbosacral plexus (TDLP) were measured on 10 cadaveric specimens. Finally, procedure of DDP was demonstrated on cadaver specimens. OA ranged from 27.68°+4.59° to 38.34°+5.97°, DM ranged from 43.44+6.29 to 68.33+12.06 mm, TLOP ranged from 16.84+2.19 to 19.64+2.36 mm, and SD ranged from 22.49+1.74 to 25.53+2.21 mm. DMSM ranged from 45.53+5.73 to 65.46+6.43 mm. APDD were between 10.51+3.59 and 12.12+4.54 mm, and TDLP were between 3.28+0.81 and 6.27+0.62 mm.DDP was successfully performed on cadaveric specimens. DDP, as a novel approach of decompression of burst fractures with pedicle rupture, can fully relieve the occupation and at the same time preserve the spinal motor unit because of no resection of intervertebral discs and no destruction of facet joints,and has certain developmental significance.

Finite element study on whether posterior upper wall fracture is a risk factor for the failure of short-segment pedicle screw fixation in the treatment of L1 burst fracture

PURPOSE

To establish the finite element model of T12 and L2 (T12-L2) pedicle screw fixation for severe L1 burst fracture, and quantitatively simulate and analyze the screw stress and vertebral displacement in different degrees of L1 posterior upper wall fracture (PUWF), and evaluate whether PUWF degree is a risk factor for fixation failure.

METHODS

The data of 6 healthy volunteers were used to establish a finite element model of T12-L2 pedicle screw fixation for type A severe burst fractures. The stress and displacement of the conventional and Schanz pedicle screws for the different degrees of PUWF (including the anterior upper wall of the vertebral canal and the bipedicle) were evaluated.

RESULTS

The maximum stress and L1 displacement of conventional and Schanz pedicle screws were positively correlated with the severity of the PUWF (P<0.05). During anterior flexion, the maximum stress of conventional pedicle screws for 70% type I were 538.3±59.75MPa and the maximum stress of Schanz pedicle screws for 90% type Ⅱ, 90% type Ⅲ and 70% type IV fractures were close to the fatigue threshold. The maximum stress during anterior flexion were significantly higher than those during posterior extension, bending and rotation (P<0.05).

CONCLUSION

The posterior upper wall fracture of vertebral body (VB) of type A burst fracture is not an independent risk factor for the failure of short-segment pedicle screw fixation (SSPSF). Anterior flexion of type A fractures combined with severe PUWF of VB was a risk factor for the failure of SSPSF.

Analysis of the Effect and Prognostic Factors Associated with Postural and Instrumental Reduction in Thoracolumbar Burst Fractures

Background:

Axial load on thoracolumbar junction, both mechanical and anatomical transitional zone, causes the compression and flexion of the spine, and consequently thoracolumbar burst fractures.

Objective:

This study aimed to investigate the effect and prognostic factors associated with the postural and instrumented reduction on the restoration of vertebral height and kyphosis angle in thoracolumbar burst fractures.

Material and Methods:

This retrospective cohort study was conducted on 41 patients with A3, A4, and B type thoracolumbar burst fractures, subjected to postural and instrumented reduction for the restoration of vertebral height and kyphosis angle. The magnitude and correction of kyphotic deformity and percentage of vertebral body collapse were measured before and after postural reduction, and after instrumental insertion to find if they were affected by fracture type and level, time-to-surgery, and use of pedicular screws at the fractured level.

Results:

Postural and instrumental reduction significantly improved both the kyphosis angle and the percentage of vertebral body height, regardless of AO types (p.value <0.001 and p.value <0.001, respectively). AO type A3, and A4 comparing to type B, has better restoration of kyphosis angle by postural (p-value=0.013, p-value=0.007, respectively) and instrumental reduction. (p-value=0.006, p-value=0.014, respectively). Evaluation of time to surgery showed that performing operation during the first four days would result in better correction of kyphosis angle (p-value 0.015).

Conclusion:

AO type A3, and A4, time to surgery before 4 days, and fracture level at L2 were favorable prognostic factors to better restoration of kyphosis angle using both postural and instrumented reduction.

Surgical consideration for thoracolumbar burst fractures with spinal canal compromise without neurological deficit

Background

For thoracolumbar burst fractures with spinal canal compromise but no neurological deficit, is it necessary to perform additional laminectomy decompression after the currently accepted posterior pedicle-screw internal fixation?

Methods

Patients were divided into two groups: decompression group (Group A) and nondecompression group (Group B). A retrospective analysis of the posterior vertebral body height of the fractured vertebral body, the ratio of the volume of the spinal canal, and the change of the Cobb angle, relative to the corresponding preoperative values, was conducted to analyse the reasons for choosing different surgical methods.

Results

Compared the intraoperative findings after fixation with the preoperative data, in Group A, the posterior vertebral body height of the fractured vertebral body was not significantly restored, the volume ratio of the spinal canal was not significantly improved, and the Cobb angle was not significantly reduced (p ​> ​0.05). In comparison, in Group B, the posterior vertebral body height of the fractured vertebral body was significantly restored, the volume ratio of spinal canal was significantly increased, and the Cobb angle was significantly reduced (p ​< ​0.001).

Conclusion

For patients with thoracolumbar burst fractures with spinal canal compromise but no neurological deficit, if when the posterior intraoperative fixation is performed, the spinal canal fracture is partially recovered, the posterior vertebral body height of the injured vertebrae is significantly restored, the spinal canal volume ratio is significantly increased, and the large kyphosis is corrected, then the indirect decompression without the posterior laminectomy can be performed.

The translational potential of this article

This study contributes to offer treatment ​consideration for ​patients with thoracolumbar burst fracture without neurological symptoms.

A new decompression technique for upper lumbar fracture with neurologic deficit-comparison with traditional open posterior surgery

Background

Surgery is usually recommended for thoracolumbar fracture with neurologic deficit. However, traditional open posterior approach requires massive paraspinal muscles stripping, and the canal decompression may be limited and incomplete. We aimed to investigate a new approach via the Wiltse approach and the Kambin’s Triangle.

Methods

Twenty-one consecutive patients with traumatic upper lumbar fracture who received this new approach surgery between January 2015 and January 2016 constituted the new approach group. Twenty-nine patients received the traditional open posterior surgery between January 2014 and January 2015 were classified as the traditional posterior surgery group. Surgical informations including operative time, blood loss, drainage volume, hospitalization days were collected and compared among the two groups. The American Spinal Injury Association (ASIA) impairment scale and Visual Analog Score (VAS) were evaluated preoperatively, postoperatively and at 12 months follow-up.

Results

Patients in the new approach group had fewer operation time (128.3 ± 25.1 vs 151 ± 32.2 min, P = 0.01), less blood loss (243.8 ± 135.5 vs 437.8 ± 224.9 ml, P = 0.001) and drainage volume (70.7 ± 57.2 vs 271.7 ± 95.5 ml, P < 0.001), as well as shorter hospitalization stay than the traditional posterior surgery group (6.6 ± 1.8 vs 8.5 ± 2.4 d, P = 0.004). Similar neurologic recovery according to ASIA grade was achieved in both groups (Recovery index: 0.90 ± 0.53 vs 0.86 ± 0.51, P = 0.778). While the pain level was significantly lower in the new approach group postoperatively (2.6 ± 0.7 vs 3.5 ± 0.9, P < 0.001) and at 12 months follow-up (1.4 ± 0.9 vs 2.4 ± 0.8, P < 0.001).

Conclusion

The present new approach was successfully applied in the treatment of upper lumbar fracture with neurologic deficit. It can reduce iatrogenic trauma and achieve similar or better outcomes compared to the traditional posterior surgery.

Multiple parameters for evaluating posterior longitudinal ligaments in thoracolumbar burst fractures

BACKGROUND

The posterior longitudinal ligament plays a key role in spinal stability. The purpose of this study was to determine the injuries of the posterior longitudinal ligament (PLL) in thoracolumbar burst fractures.

PATIENTS AND METHODS

Patients suffering a thoracolumbar burst fracture from January 2011 to December 2015 were divided into an intact group and a disrupted group according to the status of the PLL. Mid-sagittal canal diameter, width and height of bone fragments, inversion angle and horizontal rotation angle of bone fragments and local kyphosis angle were measured. Anterior, middle and posterior vertebrae compression ratio, mid-sagittal diameter compression ratio, ratio of height of bone fragments occupying the posterior wall of the injured vertebral body and ratio of the width of bone fragment occupying the transverse canal diameter were calculated.

RESULTS

A total of 95 patients were included in the study including 52 patients in the intact group and 43 patients in the disrupted group. There were significant differences on anterior and posterior vertebrae compression ratio, mid-sagittal diameter compression ratio, inversion angle and horizontal rotation angle of bone fragment (P  0.05) between the two groups. Injury of the PLL showed a positive correlation with the mid-sagittal diameter compression ratio and inversion angle of bone fragment (P  0.05).

CONCLUSION

The mid-sagittal diameter compression ratio and inversion angle of bone fragment can be used to assess the status of the PLL in thoracolumbar burst fractures. When the mid-sagittal diameter compression ratio was 52% and the inversion angle of the bone fragment was 33° the PLL was likely to be disrupted.

Femoral nonunion with segmental bone defect treated by distraction osteogenesis with monolateral external fixation

BACKGROUND

Currently, the common treatment for femoral nonunion with large segmental bone defect is difficult and complex. The effective surgical methods are rare, include vascularized bone grafting, Masquelet technique and Ilizarov distraction osteogenesis. The objective of this study is to investigate the outcomes of segmental femoral defects treated with monolateral external fixation using the distraction osteogenesis.

METHODS

We retrospectively analyzed patients with femoral nonunion with segmental bone defects (> 6 cm) between January 2010 and January 2014 in our single trauma center. All patients were treated by distraction osteogenesis with monolateral external fixation. All surgeries were performed by the same surgeon. Bone union, duration of distraction osteogenesis in days, time to consolidation in months, external fixation index (EFI), complications, and additional surgical interventions were recorded postoperatively. The modified Application of Methods of Illizarov (ASAMI) criteria were used to evaluate the operative effectiveness.

RESULTS

Forty-one patients were enrolled in this study for analysis. The length of the bone defect ranged from 6 to 17 cm. All patients eventually achieved healing, and no patient experienced recurrence of infection or newly developed infection. The average time needed for healing was 13 months. In terms of the incidence of complications, 3 cases axial deviations, 5 cases docking site nonunion, 23 cases pin-tract infection, 14 cases knee joint stiffness or their joint mobility declined, 2 cases osteogenesis insufficient in the distraction area,1 case refracture, and 2 cases loose external fixation pins. In terms of the evaluations of fracture healing and function, 30 patients excellent, 6 patients good, 5 patients fair, and 0 patient poor. In terms of postoperative function evaluations, 21 patients excellent, 9 patients good, 7 patients fair, and 4 patients poor.

CONCLUSION

For patients with femoral nonunion with large segmental bone defects, the monolateral external fixation can provide effective stability, improve compliance, and reduce complications.