Thoracolumbar Burst Fractures Research Articles

Minimally invasive reduction of thoracolumbar burst fracture using monoaxial percutaneous pedicle screws: Surgical technique and report of radiological outcome.

To describe the reduction technique of thoracolumbar burst fracture using percutaneous monoaxial screws and its radiological outcomes compared to polyaxial screws. All surgeries were performed by minimally invasive technique with either percutaneous monoaxial or percutaneous polyaxial screws inserted at adjacent fracture levels perpendicular to both superior end plates. Fracture reduction is achieved with adequate rod contouring and distraction maneuver. Radiological parameters were measured during preoperation, postoperation, and follow-up. A total of 21 patients were included. Eleven patients were performed with monoaxial pedicle screws and 10 patients performed with polyaxial pedicle screws. Based on AO thoracolumbar classification system, 10 patients in the monoaxial group had A3 fracture type and 1 had A4. In the polyaxial group, six patients had A3 and four patients had A4. Total correction of anterior vertebral height (AVH) ratio was 0.30 ± 0.10 and 0.08 ± 0.07 in monoaxial and polyaxial groups, respectively (p < 0.001). Total correction of posterior vertebral height (PVH) ratio was 0.11 ± 0.05 and 0.02 ± 0.02 in monoaxial and polyaxial groups, respectively (p < 0.001). Monoaxial group achieved more correction of 13° (62.6%) in local kyphotic angle compared to 8.2° (48.0%) in polyaxial group. Similarly, in regional kyphotic angle, 16.5° (103.1%) in the monoaxial group and 8.1° (76.4%) in the polyaxial group were achieved. Monoaxial percutaneous pedicle screws inserted at adjacent fracture levels provided significantly better fracture reduction compared to polyaxial screws in thoracolumbar fractures.

Dynamics of spinal cord compression with different patterns of thoracolumbar burst fractures: Numerical simulations using finite element modelling

BackgroundIn thoracolumbar burst fractures, spinal cord primary injury involves a direct impact and energy transfer from bone fragments to the spinal cord. Unfortunately, imaging studies performed after the injury only depict the residual bone fragments position and pattern of spinal cord compression, with little insight on the dynamics involved during traumas. Knowledge of underlying mechanisms could be helpful in determining the severity of the primary injury, hence the extent of spinal cord damage and associated potential for recovery. Finite element models are often used to study dynamic processes, but have never been used specifically to simulate different severities of thoracolumbar burst fractures. MethodsPreviously developed thoracolumbar spine and spinal cord finite element models were used and further validated, and representative vertebral fragments were modelled. A full factorial design was used to investigate the effects of comminution of the superior fragment, presence of an inferior fragment, fragments rotation and velocity, on maximum Von Mises stress and strain, maximum major strain, and pressure in the spinal cord. FindingsFragment velocity clearly was the most influential factor. Fragments rotation and presence of an inferior fragment increased pressure, but rotation decreased both strains outputs. Although significant for both strains outputs, comminution of the superior fragment isn't estimated to influence outputs. InterpretationThis study is the first, to the authors' knowledge, to examine a detailed spinal cord model impacted in situ by fragments from burst fractures. This numeric model could be used in the future to comprehensively link traumatic events or imaging study characteristics to known spinal cord injuries severity and potential for recovery.

Seizure-induced thoracolumbar burst fractures - Not to be missed.

While rare, post-ictal thoracolumbar burst fractures are commonly missed due to confounding factors, resulting in delayed treatment and the potential for serious neurological deficits. This paper serves as a call for a high-degree of clinical suspicion when treating post-ictal patients to ensure they undergo a focused neurological examination of the lower extremities. If unresponsive/uncooperative, spinal precautions should be maintained until the spine can be cleared clinically or radiographically. In all events, if the patient is complaining of musculoskeletal pain possibly originating from the spine, radiographic evaluations are warranted to prevent possible deficits caused by a missed thoracolumbar fracture.

Thoracolumbar burst fractures associated with incomplete neurological deficit in patients under the age of 40: Is the posterior approach enough? Surgical treatment and results in a case series of 10 patients with a minimum follow-up of 2 years

IntroductionSurgical management of thoracolumbar burst fractures is controversial. While the goals of surgical treatment are well accepted (i.e., fracture reduction and stabilization, neural elements decompression, and segmental angular deformity correction), the choice of the best surgical approach (i.e., posterior vs. anterior vs. combined approach) remains controversial. Several studies have debated the advantages of each surgical approach but there is no definitive evidence available to date, particularly in young adult patients. The aim of this study was to assess whether posterior approach alone can be a valid surgical treatment for patient under the age of 40 affected by thoracolumbar burst fractures and incomplete neurological deficits. Material and MethodsA total of 10 consecutive patients affected by thoracolumbar burst fractures associated with incomplete neurological deficits treated at our institution from January 2015 to February 2017 were included in our study. All patients were under the age of 40 at the time of injury and underwent decompression and stabilization using the posterior surgical approach alone. Demographics, clinical, and radiographic parameters were recorded preoperatively, postoperatively and at the latest available follow-up. The minimum follow-up was set at 2 years post-operatively. ResultsThe mean operative time was 303.6 min (range, 138–486). Average blood loss was 756 mL (range, 440–2100). Nine out of ten patients returned to a normal neurological status after surgery while 1 patient showed some improvement but did not recover completely. Segmental kyphotic deformity improved from a mean of 21.8° before surgery to 14.8° at the time of the last follow-up. The anterior and posterior wall height of the fractured vertebra was restored with an average of 4 mm. The Visual Analogue Scale score reported an improvement from the mean preoperative value of 7.92 to 1.24 at the last follow-up; 8 out of 10 patients resumed physical activity while all of them returned to work. ConclusionsA single posterior surgical approach is an acceptable option in terms of clinical, radiological and functional outcomes at 2 years follow-up in patients under the age of 40 presenting with a thoracolumbar burst fracture and neurological deficit.

A study of pedicle screw fixation combined with an intermediate screw at the fracture level for treatment of thoracolumbar burst fractures without Neurological injury

A study of pedicle screw fixation combined with an intermediate screw at the fracture level for treatment of thoracolumbar burst fractures without Neurological injury

Percutaneous short-segment pedicle instrumentation assisted with O-arm navigation in the treatment of thoracolumbar burst fractures

ObjectTo compare the clinical and radiological outcomes of O-arm navigation assisted percutaneous pedicle fixation and open freehand pedicle fixation in treatment of AO type A3 thoracolumbar burst fractures (TBFs) without neurological deficit. MethodsThis retrospective study involved 72 patients with type A3 TBFs who underwent O-arm navigation assisted percutaneous pedicle fixation (MIS group) or open freehand posterior pedicle fixation (OPPF group) from September 2015 to December 2017. Demographic data and clinical characteristics were comparable between these two groups before surgery. Operating time, intraoperative blood loss, and the time of hospitalisation stay were analysed. Visual analog scale (VAS) scoring and Oswestry disability index (ODI) was assessed for each patient pre- and postoperatively. Radiographic follow-up was assessed by the Local kyphosis angle (LKA), Vertebral wedge angle (VWA), and Anterior body height (ABH). The accuracy of screw placement was examined by computed tomography. ResultsThe two groups were matched in terms of demographic and clinical features. Intraoperative blood loss was significantly less in the MIS group compared to the OPPF group (p < 0.05). The average time for hospitalisation stay in the MIS group was significantly shorter than OPPF group (p < 0.05). However, the operative time revealed no significant difference between two groups (p > 0.05). Meanwhile, the VAS score and ODI score in the MIS group were significantly lower than that in the OPPF group after surgery (p < 0.05). Radiographic assessments revealed no obvious difference between the 2 groups immediately after surgery or at the final follow-up (p > 0.05); The accuracy rate of pedicle screw position in the MIS group was higher than OPPF group (97.8% vs 78.5%, respectively; p < 0.001). No deep wound infection, additional surgery, implant failure, or neurological complications were recorded in either group. ConclusionsPercutaneous short-segment pedicle instrumentation assisted with O-arm navigation represents an effective and safe alternative for type A3 TBFs. It has several advantages compared with open approach, including less blood loss, shorter hospitalisation, less postoperative pain, higher accuracy of pedicle screw placement, and faster recovery period in treating TBFs. However, it requires a longer learning curve and long-term results have to be studied in other well-designed studies. The translational potential of this articlePercutaneous short-segment pedicle instrumentation assisted with O-arm navigation represents an effective and safe alternative for type A3 TBFs. The utilization of O-arm navigation and percutaneous pedicle screw fixation guaranteed the high accuracy of screw placement, protected staff from radiation exposure and offered benefits of minimal invasive technique.

Anterolateral Versus Posterior Approach in Management of Lower Dorsal and Upper Lumbar Traumatic &amp; Pathological Spine Fractures

Purpose: comparing anterolateral versus posterior approach in decompression and stabilization of spine. Study design: prospective comparative study. Patients and Method: thirty patients have lower dorsal and upper lumbar spine fractures operated upon in the period from January 2016 to July 2017. Results: Surgical management of thoracolumbar burst and pathological fractures, Anterolateral approach have not significant superior to posterior approach in terms of recovery neurological function and maintaining normal life activities. Anterior approach was better than posterior approach in rapid improvement of sphincteric control in patients with incomplete cord injury with sphincteric troubles.

A study of pedicle screw fixation combined with an intermediate screw at the fracture level for treatment of thoracolumbar burst fractures without Neurological injury

A study of pedicle screw fixation combined with an intermediate screw at the fracture level for treatment of thoracolumbar burst fractures without Neurological injury

Minimally Invasive Decompression and Intracorporeal Bone Grafting Combined with Temporary Percutaneous Short-Segment Pedicle Screw Fixation for Treatment of Thoracolumbar Burst Fracture with Neurological Deficits

We evaluated the clinical and radiographic outcomes of patients with thoracolumbar burst fractures and neurological deficits treated with minimally invasive decompression and intracorporeal bone grafting combined with percutaneous short-segment stabilization. Patients with thoracolumbar burst fractures and neurological deficits underwent minimally invasive decompression and intracorporeal bone grafting combined with percutaneous short-segment stabilization. Instrumentation was removed approximately 1 year after vertebral fracture union. The clinical and radiographic outcomes were analyzed. The mean operative duration and intraoperative bleeding volume were 135 ± 63 minutes and 120 ± 200 mL, respectively. The average American Spinal Injury Association impairment scale scores had significantly improved at the final follow-up examination. The visual analog scale score had decreased from 7.8 ± 1.1 preoperatively to <2.9 ± 1.3 (P < 0.05) at 1 week postoperatively. The Oswestry disability index had decreased from 86.1 ± 8.8 preoperatively to 15.9 ± 6.4 (P < 0.05) at 1 year postoperatively. The canal stenosis index had improved from 43.4% ± 12.0% to 93.8% ± 4.8% (P < 0.05). The sagittal Cobb angle had been corrected from 17.8° ± 7.5° to 4.0° ± 1.9° (P < 0.05) and remained at 4.9° ± 2.0° (P > 0.05) at 1 year postoperatively. The sagittal index had been corrected from 16.6° ± 6.1° to 0.3° ± 4.6° (P < 0.05) and remained at 1.5°+ 4.5° (P > 0.05) at 1 year postoperatively. The anterior vertebral height had increased from 49.3% ± 11.1% to 97.6% ± 6.5% (P < 0.05) and remained at 95.7% ± 6.0% (P > 0.05) at 1 year postoperatively. After implant removal, the total kyphosis correction losses were 1.5° ± 0.8° for the Cobb angle, 2.0° ± 1.1° for the sagittal index, and 3.4% ± 2.1% for the anterior vertebral height. One pullout screw and one broken rod were found in 1 patient each. Minimally invasive decompression and intracorporeal bone grafting combined with percutaneous short-segment fixation yielded satisfactory results in decompression and immediate kyphosis correction. Additionally, this procedure resulted in maintenance of the vertebral height and prevented late correction loss after implant removal.

Efficacy of Short and Mono segment Spinal Fixations in Traumatic Incomplete Thoracolumbar Burst Fractures

Background: Controversies still mount over the long segment, short segment and mono segment screw fixation for traumatic thoracolumbar spine burst fractures. This article aims to provide our initial experience of the effectiveness of these management modalities with additive focus on their potential benefits upon preventing the loss of correction over time.&#x0D; Methods: We included all operated cases of thoracolumbar fractures presenting with the ASIA grade of above ‘C’ between December 2014to December 2017 in a retrospective manner in terms of operative time, estimated intra-operative blood loss, any post-operative surgical wound complications, implant cost, average time lapse for the patients to return to physiotherapy and the follow up radiological imaging at 6 months.&#x0D; Results: Long segment fixation is comparatively more time consuming with considerable blood loss and high incidence of postoperative wound complications. We observed that both short as well as mono segment crew fixations had similar incidences with regards to the common complications pertaining to the spinal implant placement procedures.&#x0D; Conclusions: Both short and mono-segment fixation procedures resulted in comparable short and long term results. Though long segment fixation is comparatively more stable, it is, however, expensive with a higher incidence of other postoperative complications.

Effects of Bracing on Clinical and Radiographic Outcomes Following Thoracolumbar Burst Fractures in Neurologically Intact Patients: A Meta-Analysis of Randomized Controlled Trials.

We conducted a meta-analysis of randomized trials to determine the effect of the use of an orthosis (as compared with no orthosis) on clinical and radiographic outcomes in neurologically intact patients with thoracolumbar burst fractures. Optimal nonoperative treatment of thoracolumbar burst fractures in neurologically intact patients remains inconclusive. Conventional care prescribes spine precautions and a thoracolumbar orthosis. Recent studies have suggested that patients with stable burst fractures can obtain comparable outcomes with or without bracing. We performed a comprehensive search of the literature with use of OVID MEDLINE, Embase, and the Cochrane Library. Two independent reviewers assessed the eligibility of studies and the risk of bias of included trials. We analyzed several outcomes: the Roland Morris Disability Questionnaire (RMDQ) score, Oswestry Disability Index (ODI), Short Form-36 Physical and Mental Component Summary (SF-36 PCS and MCS) scores, pain, length of stay, treatment failure, and kyphotic angle. We used weighted mean differences and standardized mean differences in a random-effects model. We included 3 studies with a total of 59 patients who were managed with use of a brace and 60 patients who were managed without a brace. There was no significant difference between groups treated with or without an orthosis in terms of SF-36 PCS, SF-36 MCS, RMDQ/ODI, pain, length of stay, failure rates, or kyphosis angle at baseline or 6-month follow-up. Similar outcomes were seen at long-term follow-up of ≥5 years. This meta-analysis suggests that neurologically intact patients with thoracolumbar burst fractures obtain similar clinical and radiographic outcomes with or without bracing at both short and long-term follow-up. Routine use of orthoses following these fractures may incur substantial costs and patient morbidity without clinical benefit. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Effect of loss of correction on functional outcomes in thoracolumbar burst fractures treated with short segment posterior instrumentation

Aim: Burst fractures are defined as vertebra fractures involving the anterior and middle columns and are associated with kyphotic deformity and retropulsion of bone fragment into the spinal canal. Although their treatment is controversial in the literature, use of transpedicular screws and short segment posterior instrumentation are increasingly common practices. The aim of this study is to investigate the radiological and functional outcomes of thoracolumbar vertebra burst fractures treated with short segment posterior instrumentation and to examine the effects of postoperative correction loss on these results.Methods: Patients who were surgically treated for thoracolumbar burst fractures and prospectively followed-up between 2000-2003 were scanned retrospectively for this cohort study. 48 patients were included in the study, of which 18 were females (37.5%) and 30 were males (62.5%). Denis Pain Scale (DPS) and Denis Work Scale (DWS) were used for functional analysis. Cobb angles that were measured preoperatively, on the first postoperative day, and at the last follow-up visit were used for evaluation of radiological outcomes. Spinal stenosis and remodelization rates were also calculated by computerized tomography obtained preoperatively and at the last follow-up. One-way ANOVA and Pearson correlation tests were used for statistical analysis.Results: No patient had any chronic pain complaints, and none were unable to work. The mean Cobb angles in the preoperative, early post-operative and final controls were measured as 23.2, 4.9, and 12.3 degrees, respectively. While preoperative mean Cobb angle and mean correction were positively correlated (r=0.85, P&lt;0.001), there was no correlation between preoperative mean Cobb angle and loss of correction (r=0.27, P=0.43). There was a correlation between correction and loss of correction (r=0.38, P=0.008). Spinal stenosis, which was 35.7% preoperatively, reduced to 17.1% in the last follow-up. The mean remodelization was 51.3%, which was significant (P&lt;0.001). Loss of correction was found significant in patients with poor DWS (P=0.003), and no such relationship was found in DPS. No correlation was found between the Cobb angle at the last follow-up, DPS and DWS. Conclusion: In conclusion, the loss of correction after short segment posterior instrumentation and fusion surgery is significantly higher in thoracolumbar burst fractures, especially when intraoperative correction exceeds 15 degrees. Denis Work Scale was significantly worse in patients with loss of correction above 10 degrees. The degree of loss of correction at the last follow-up is directly related to clinical and functional outcomes.

Anterior versus posterior approach in traumatic thoracolumbar burst fractures deemed for surgical management: Systematic review and meta-analysis

Uncertainties remain regarding the optimal surgical approach in the treatment of traumatic thoracolumbar burst fractures. We aim to compare the surgical, radiological and functional outcomes in anterior versus posterior approaches in patients with traumatic thoracolumbar burst fractures deemed for surgical management. A systematic review adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines was performed. Qualitative analysis and where suitable, meta-analysis were performed to compute pooled estimates of the differences between anterior and posterior approaches. A total of six studies (three observational, one prospective non-randomized trial, two randomized controlled trials) were included. There were no cases of postoperative neurological decline. Meta-analysis demonstrates a longer duration (Mean Difference (MD) + 81.68, 95% CI 39.20 to 123.16, p < 0.001) and increased estimated blood loss (MD + 426.27, 95% CI 119.84 to 732.70, p = 0.006) for the anterior approach. No difference between approaches was found regarding length of hospital stay, late postoperative kyphotic angle, construct failure rate, instrumentation revision rate, rate of return to work, and total hospital charges. Limitations include the small number of, and heterogeneity across studies. Given the similarities in neurological, radiological and functional outcomes between the two approaches, the longer duration and estimated blood loss in the anterior approach should be a point of consideration when selecting the surgical approach. There is an urgent need for contemporary, high quality research in this area.

Outcomes of Thoracolumbar Burst Fracture in Patients With Osteoporosis Without Neurologic Symptoms: Analysis of Three Different Surgical Approaches

This study aimed to compare the outcomes of thoracolumbar burst fractures in patients with osteoporosis without neurologic symptoms according to the surgical approach. The patients in group A underwent percutaneous balloon kyphoplasty, those in group B underwent minimally invasive percutaneous reduction and internal fixation, and those in group C underwent open reduction with bone graft fusion and internal fixation. Fracture reduction was assessed by X-ray. The operative time in group A was shorter than that in groups B and C, with less intraoperative blood loss and shorter hospital stay. The intraoperative blood loss was less in group B than in group C, with shorter hospital stay. The postoperative visual analog scale scores were lower than the preoperative scores in each group. Cobb's angle of the injured vertebra in the last follow-up was larger in group A than in groups B and C. Regarding complications, in group A, nine patients developed postoperative bone cement leakage that required no specific treatment. In group B, one patient developed subcutaneous hematoma that healed well after treatment. The screw channel was loosened in two patients without symptoms; the screws were removed 1 year later. In group C, delayed incision healing was found in five patients. All three surgical approaches safely and effectively relieved the lower back pain in patients with thoracolumbar burst fracture with osteoporosis but without neurologic symptoms.

Surgical outcomes in thoracolumbar fractures with pure conus medullaris syndrome

BackgroundPure conus medullaris syndrome is defined as a combination of signs and symptoms of bladder/bowel incontinence and impotence without the presence of lower limbs weakness. The purpose of the study is to assess the recovery of voiding, sexual, and sensory function in patients with isolated conus medullaris syndrome after surgical treatments. MethodsFrom January 2005 to December 2012, patients with a single level burst fracture with pure conus medullaris syndrome were assessed. Level of injury, use of steroid, surgical time, surgical approach, preoperative radiographic parameters, and types of neurogenic bladder were recorded. Bladder function was evaluated using urodynamic study; sexual function was assessed by self-report questionnaire. The final outcomes were focused on the recovery of voiding, sexual, and sensory function. ResultsEight patients met the criteria of pure conus medullaris syndrome with thoracolumbar burst fracture. The injury level were all located at L1 vertebra. There were 6 males and 2 females. Four patients had overactive neurogenic bladder, and the other 4 patients had underactive type. At final, five patients regained self-voiding function, and three required intermittent catheterization. Two male patients were sexually active, and four male patients had some sexual dysfunction. Two female patients could have normal sexual intercourse but the frequency decreased. One female patients had prolonged perineum numbness at final follow-up. ConclusionsAlthough extremely rare, pure conus medullaris syndrome may occur with L1 burst fracture. Despite surgical treatment, only one half of the patients regained normal bladder and sexual function.

Clinical application of extracorporeal pneumatic reduction combined with bone-filled mesh bag implantation for the treatment of thoracolumbar osteoporotic burst fracture without spinal cord injury

To compare the clinical efficacy of pneumatic reduction combined with bone-filled mesh bag implantation and pneumatic reduction combined with kyphoplasty in the treatment of thoracolumbar burst fracture without spinal cord injury. The clinical data of 160 patients with thoracolumbar osteoporotic burst fracture without spinal cord injury treated from January 2014 to July 2017 were retrospectively analyzed. There were 66 males and 94 females, aged from 72 to 84 years old with an average of 76.4 years old. The patients were divided into two groups according to different surgical methods, including 80 cases of pneumatic reduction combined with bone-filled mesh bag implantation(treatment group) and 80 cases of pneumatic reduction combined with kyphoplasty(control group). The intraoperative bone cement leakage rate was compared between two groups. The height of the injured vertebrae was measured by X-rays preoperatively and 6-month postoperatively in order to assess height loss of injured vertebrae. VAS score and ODI score were used for follow-up to assess lumbar back pain and autonomic dysfunction before surgery and 2 weeks, 6 months, 1 year after surgery. In treatment group, 3 cases occurred bone cement leakage during operation and leakage rate was 3.75%(3/80); In control group, 14 cases had cement leakage with leakage rate of 17.5%; The difference between two groups was statistically significant(P<0.05). All patients were followed up for 13 to 24 months with an average of 14.6 months. Among them, 2 cases occurred postoperative infections which were superficial infections. After oral antibiotics and outpatient treatment infections were controlled. At 6 months after surgery, the height of the injured vertebra was measured by X-ray. Treatment group recovered (5.12±1.31) % and control group recovered (14.11±1.17) %. The difference between two groups was statistically significant (P<0.05). At 1 year after surgery, ODI score was 4.03±1.62 in treatment group and 10.03±1.54 in control group. The difference between two groups was statistically significant(P<0.05). VAS score was 1.03±0.62 in treatment group and 2.67±0.55 in control group. The difference between groups was statistically significant(P<0.05). Extracorporeal pneumatic reduction combined with bone-filled mesh bag implantation technique can significantly reduce the occurrence of intraoperative cement leakage in the treatment of thoracolumbar osteoporotic burst fractures, effectively improve reposition of the injured vertebrae, relieve the pain and recover the function of lower back. However, high price of bone-filled mesh bags obstructs its clinical popularization.

Comparison of three methods of bone grafting in the treatment of thoracolumbar burst fracture

Objective To compare and the advantages and disadvantages of 3 methods of bone grafting in the posterior treatment of thoracolumbar burst fracture. Methods A retrospective analysis was conducted of 258 thoracolumbar burst fractures treated with posterior short-segment fixation from March 2013 to March 2015 at Orthopedic Department One, Foshan Hospital of Traditional Chinese Medicine. Of them, 87 were treated with transpedicular bone grafting (group A), 87 with laminar and intertransverse process bone grafting (group B) and 84 with small joint turnover plus bone grafting (group C). The 3 groups were compared in terms of cobb angle, loss of correction, bony fusion, internal fixation failure, and Oswestry disability index (ODI). Results The 3 groups were comparable due to insignificant differences in the preoperative general data between them (P>0.05). The cobb angles in the 3 groups at one week after operation (4.9°±1.0°, 4.8°±0.6° and 4.8°±0.6°) and at the final follow-up (6.1°±1.5°, 14.5°±3.7° and 15.3°±4.1°) were significantly smaller than those before operation (27.5°±4.9°, 27.6°±4.6° and 27.6°±4.2°) (P<0.05). The cobb angles in groups B and C at the final follow-up were significantly larger than those at one week after operation (P<0.05). At the final follow-up, both the cob angles and the loss of kyphoplasty correction in groups B and C were significantly larger than in group A (P<0.05). The fusion rate in group A (100%) was significantly larger than in group B (80.5%) and C (76.2%). There were no significant differences between the 3 groups in the rate of internal fixation failure (0, 1.1% and 2.4%) (χ2=2.108, P=0.348). The ODI for the 3 groups at 6 months after operation (28.5±4.1, 28.7±3.9 and 28.8±3.7) and at the final follow-up (10.7±2.6, 11.0±2.7 and 11.4±3.1) were all significantly lower than the preoperative values (94.3±0.7, 94.4±0.9 and 94.4±0.8) (P<0.001). In all the patients, the ODI at the final follow-up was significantly lower than that at 6 months after operation(P<0.001). Conclusions In the treatment of thoracolumbar burst fractures, all the posterior approach plus transpedicular bone grafting, posterolateral bone grafting and reversed bone grafting plus short segmental internal fixation can effectively restore vertebral height and result in a high rate of fusion. Although the latter 2 methods of bone grafting are effective, they may be disadvantageous in leading to long-term loss of vertebral height and kyphosis correction. Key words: Thoracic vertebrae; Lumbar vertebrae; Fractures, bone; Bone graft

Biomechanical effects of posterior pedicle fixation techniques on the adjacent segment for the treatment of thoracolumbar burst fractures: a biomechanical analysis

Posterior pedicle fixation technique is a common method for treating thoracolumbar burst fractures, but the effect of different fixation techniques on the postoperative spinal mechanical properties has not been clearly defined, especially on adjacent segments. A finite element model of T10-L2 with moderate T12 vertebra burst fracture was constructed to investigate biomechanical behavior of three posterior pedicle screw fixation techniques. Compared with traditional short-segment 4 pedicle screw fixation (TS-4) and intermediate long-segment 6 pedicle screw fixation (IL-6), mono-segment 4 pedicle screw fixation (MS-4) provides a safer surgical selection to prevent the secondary degeneration of adjacent segments in the long-term.

The Predictive Value of the Load Sharing Classification Concerning Sagittal Collapse and Posterior Instrumentation Failure: A Systematic Literature Review.

Study design:Systematic review.Objective:In 1994, the Load Sharing Classification (LSC) was introduced to aid the choice of surgical treatment of thoracolumbar spine fractures. Since that time this classification system has been commonly used in the field of spine surgery. However, current literature varies regarding its use and predictive value in relation to implant failure and sagittal collapse. The objective of this study is to assess the predictive value of the LSC concerning the need for anterior stabilization to prevent sagittal collapse and posterior instrumentation failure.Methods:An electronic search of PubMed, Medline, Embase, and the Cochrane Library was performed. Inclusion criteria were (1) cohort or clinical trial (2) including patients with thoracolumbar burst fractures (3) whose severity of the fractured vertebrae was assessed by the LSC.Results:Five thousand eighty-two articles have been identified, of which 21 articles were included for this review. Twelve studies reported no correlation between the LSC and sagittal collapse or instrumentation failure in patients treated with short-segment posterior instrumentation (SSPI). Seven articles found no significant relation; 5 articles found no instrumentation failure at all. The remaining 9 articles experienced failure in patients with a high LSC or recommended a different surgical technique.Conclusions:Although the LSC was originally developed to predict the need for anterior stabilization in addition to SSPI, many studies show that SSPI only can be sufficient in treating thoracolumbar fractures regardless of the LSC. The LSC might have lost its value in predicting sagittal collapse and posterior instrumentation failure.

Comparing the Biomechanical Stability of Cortical Screw Trajectory Versus Standard Pedicle Screw Trajectory for Short- and Long-Segment Posterior Fixation in 3-Column Thoracic Spinal Injury.

Information on the performance of posterior fixation with cortical screw (CS) versus pedicle screw (PS) trajectories for stabilizing thoracolumbar burst fractures is limited. Therefore, we sought to analyze stability with CS versus PS in short- and long-segment fixations using a 3-column spinal injury model. Nondestructive flexibility tests: (1) intact, (2) intact + short fixation, (3) intact + long fixation, (4) after burst fracture, (5) short fixation + burst fracture, and (6) long fixation + burst fracture using thoracic spine segments (7 CS, 7 PS). With CS, the range of motion (ROM) was significantly greater with short-segment than with long-segment fixation in all directions, with and without burst fracture (P ≤ .008). With PS and burst fracture, ROM was significantly greater with short fixation during lateral bending and axial rotation (P < .006), but not during flexion-extension (P = .10). Groups with CS versus PS were not significantly different after burst fracture during flexion-extension and axial rotation, with short (P ≥ .58) or long fixation (P ≥ .17). During lateral bending, ROM was significantly greater with CS versus PS, without burst fracture (long fixation, P = .02) and with burst fracture (short and long fixation, P ≤ .001). CS trajectory is a valid alternative to PS trajectory for thoracic spine fixation in 3-column spinal injuries, and long-segment fixation is superior to short-segment fixation with either.