Introduction. The management of thoracolumbar burst fractures is controversial. The goal of our study was to evaluate whether the psychological factors or the late spinal deformities influence outcome and in particular quality of life following surgical treatment of burst fractures of the thoracolumbar spine. Material and methods. In a retrospective analysis, we evaluated outcome in 45 patients in whom burst fractures of the thoracolumbar spine without neurological deficits were surgically treated between April 2001 and November 2004. For this purpose, patient charts, surgery reports and x-ray images were analyzed consecutively. 29 patients could be examined physically and the outcome could be evaluated with VAS spine core, quality of life according to short-form 36 (SF36) and Beck Depression Inventory (BDI) with a minimum follow up of 30 months. Results. Mean VAS spine score was 60±26. Neither VAS spine score, nor quality of life results correlated with the following radiological findings: vertebral body angle, sagittal index and height of cranial disc space of the vertebra. Beck Depression Inventory (BDI) correlated with SF-36 score and VAS spine score (p< 0.05). Patients who were depressed showed significantly worse results in relation to the VAS spine score and the SF36 score (p< 0.01). Conclusion. For the first time, we could show, that psychological factors have high influence on functional outcome and health related quality of life in operative treated thoracolumbar burst fracture independent of x-ray findings. Therefore, we recommend inclusion of psychological components in the treatment and outcome-evaluation of the thoracolumbar burst fracture in future

Purpose: The mechanical integrity of vertebral bone is compromised when metastatic cancer cells migrate to the spine, rendering it susceptible to burst fracture under physiologic loading. Risk of burst fracture has been shown to be dependent on the magnitude of the applied load, however limited work has been conducted to determine the effect of load type on the stability of the metastatic spine. The objective of this study was to evaluate the effect of multiple loading conditions and the presence of the ribcage on a metastatically-involved thoracic spinal motion segment. Methods: A parametric biphasic finite element model was developed and validated against experimental data under axial compressive loading. Fifteen loading scenarios were analysed, including axial compression, flexion, extension, lateral bending, torsion, and combined loads. Axial loads were applied up to 800N and moment loads up to 2Nm. Multiple analyses were conducted with and without the ribcage to assess its impact on thoracic spinal stability. Vertebral bulge (VB) and load induced canal narrowing (LICN) were utilised as main outcome parameters to assess burst fracture risk. Results: For single loads, pure 800N axial loading yielded the highest level of VB (0.48mm) and LICN (0.26mm). The smallest increases in VB were measured in 1Nm pure flexion (0.018mm). Combined loading scenarios also demonstrated that axial loading is the principal factor contributing to VB, as changes in VB for combined loads were no greater than 4.35% of VB under axial loading alone. Inclusion of the ribcage was found to reduce the potential for burst fracture by 27% under axial load. Conclusions: Axial loading is the predominant load type leading to increased risk of burst fracture initiation. Rotational loading (bending, flexion and extension) led to only moderate increases in risk. The ribcage provides substantial stability to reduce overall risk of burst fracture. These findings are important in developing a more comprehensive understanding of burst fracture mechanics in the metastatic spine and in directing future modeling efforts. The results in this study may also be useful in advising less harmful activities for patients affected by lytic spinal metastases. Funding: Other Education Grant. Funding Parties: Natural Sciences and Engineering Research Council

Purpose: Stability of thoracic vertebrae affected by metastatic disease has been shown to be dependent on tumour size and bone density, but additional structural and geometric factors may also play a role in burst fracture risk assessment. The objective of this study was to use parametric finite element modeling to determine the effects of vertebral level, geometry, and metastatic compromise to the cortical shell on the risk of burst fracture initiation in the thoracic spine. Methods: An experimentally validated parametric biphasic finite element model of a metastatically involved spinal motion segment was analysed with scenarios representing motion segments from T2-T4 through T10-T12. Variations in vertebral geometry, kyphotic angulation and endplate angulation were evaluated. Additionally, four scenarios with transcortical breach of the tumour were compared to a central tumour scenario to determine the effect of cortical destruction. Vertebral bulge (VB), load induced canal narrowing (LICN), and posterior wall tensile hoop strain (PWTHS) were utilised as the main outcome parameters to assess burst fracture risk. Results: Burst fracture risk outcome parameters were largest in upper vertebrae, decreasing inferiorly at each subsequent level, with T11 exhibiting a 35.5% decrease in VB relative to T3, despite greater applied loads. An increase in endplate angles led to a 6.59% decrease in VB and a 2.38% decrease in LICN. A 5° increase in kyphotic angle further decreased VB and LICN by 7.29% and 4.34% respectively. Transcortical tumour scenarios led to an average decrease in PWTHS of 25.8%. Conclusions: Patients affected by spinal metastases in upper thoracic vertebrae may be at greater risk of burst fracture. Decreased burst fracture risk with greater thoracic kyphotic angulation may be due to a change in loading direction for curved segments, reducing the amount of pure axial load applied. Decreased tensile hoop strains are generated during loading of transcortical tumours. This may be attributed to large deformation of tumour tissue through the breach in the cortical shell, reducing the potential for burst fracture. Improved burst fracture risk assessment in the thoracic spine may motivate more informed clinical decision-making. Funding: Other Education Grant. Funding Parties: Natural Sciences and Engineering Research Council

Spinal metastatic disease can result in burst fracture and neurologic compromise. This study aims to examine the effects of tumour location, shape and surface texture on burst fracture risk in the metastatic spine using a parametric poroelastic finite element model. Tumours were found to be most hazardous in the posterior region of the vertebral body, whereas the multiple tumour scenarios reduced risk. Tumour shape may affect the mechanism of burst fracture. Serrated and smooth outer tumour surfaces yielded similar trends. These results can be used to improve guidelines for burst fracture risk assessment in patients with spinal metastases. This study aims to examine the effects of tumour location, shape and surface texture on burst fracture risk in the metastatic spine. Both tumour location and shape are important factors in assessing the risk of burst fracture in the meta-static spine. Improving risk prediction may reduce burst fracture in patients with spinal metastases. Vertebral bulge increased over 30% when the tumour was moved posteriorly. Conversely, for the multi-tumour scenarios, vertebral bulge and axial displacement decreased by 41% and 35% in comparison to a single central tumour. Anterior and lateral movement demonstrated only small effects. Vertebral bulge increased proportionally to mediolateral tumour length and axial displacement increased proportionally to superior-inferior tumour length. Similar trends were seen with smoothed and serrated tumour surfaces. Using a parametric poroelastic finite element model of a metastaticaly involved T7 spinal motion segment, fourteen single and two multi-tumour scenarios were analyzed, each comprising approximately 24% tumour volume. Ellispoidal tumours were positioned in central, anterior, posterior and lateral locations. Tumour shape was altered by adjusting tumour radii for a centrally located tumour. Tumours were modeled using smoothed and serrated outer surface configurations. Burst fracture risk was assessed by measuring maximum vertebral bulge and axial displacement under load. Tumours were found to be most hazardous in the posterior region of the vertebral body, whereas the multi-tumour scenarios reduced risk. Modeling of tumour surface texture did not impact shape or location effects. Tumour shape may affect the mechanism of burst fracture. Funding: This study was supported by the National Science and Engineering Research Council

We present a series of 14 patients presenting to the senior surgeon’s practice who sustained thoracolumbar burst fractures, with no neurological loss. The patients were treated with early mobilisation and extension bracing. We assessed their pain and disability, using VAS and ODI, and their fracture morphology. There was no statistical correlation between any measured parameter of fracture morphology and pain or disability. There was correlation between age at injury, time elapsed from injury and psychosocial aspects of the injury and the subsequent disability. The measured disability was low and compared favourably with the results of studies of patients treated surgically. We continue to treat all our neurologically intact burst fractures by early mobilisation and bracing, and take no account of fracture morphology in our decision making

Introduction: The management of thoraco-lumbar burst fractures remains controversial. Different authors have advocated immobilisation, external bracing or internal fixation by either anterior or posterior approaches. Advocates of posterior fixation have in general performed stabilisation one level above and one level below the site of the fracture, resulting in fixation of two motion segments. It is known that multi-segmental spinal fusion produces undesirable biomechanics. To stabilise the site of the fracture and avoid unnecessary fixation of an uninjured segment the senior author (T.S.) for selected patients has been using a novel technique of monosegmental fixation with placement of pedicle screws directly into the fractured vertebral body. Methods: All patients with thoraco-lumbar burst fractures admitted to St Vincents and Concord Hospitals between January 2001 and October 2003 were considered for monosegmental fixation. Patients with severe osteoporosis or complete loss of vertebral body height (“vertebra plana”) were excluded. All patients underwent surgical decompression and fixation within 10 days of injury. Fixation was obtained with 4 titanium pedicle screws and a single transverse connector (Xia System Stryker Spine). Reduction of kyphotic deformity was carried out in selected patients. Average blood loss for the procedure was 250 ml with no patients requiring transfusion. All patients had a minimum of 6 months radiological and clinical follow-up. Results: Since January 2001, 18 patients with thoracolumbar burst fractures (T10-L2) were treated with single-level pedicle screw fixation. All patients were mobilised within 10 days of surgery. One patient experienced a minor superficial wound infection. There were no other postoperative complications. All patients had a stable fusion construct at 6 weeks following surgery. No patient experienced neurological deficit or have developed a delayed kyphotic deformity. There were no instances of instrument failure. 17 out of 18 patients report no significant back pain with any limitation of function by three months following surgery. One patient reports mild mechanical lower back pain 12 months following the injury. Discussion: Single level fixation for selected cases of thoracolumbar burst fracture is a safe and effective procedure to decompress the neural elements and obtain fixation and fusion of the fractured segment. It allows for rapid mobilisation and avoids a two-level fusion procedure with its subsequent detrimental effect on spinal biomechanics. It is considerably less invasive than anterior/lateral approaches which require extensive muscle dissection, rib removal and even diaphragmatic division

Introduction The precise contribution of the posterior longitudinal ligament (PLL) and disc annulus in the burst fracture setting and their potential relative roles during intra operative reduction manoeuvres remains unclear. The anatomical attachments of the posterosuperior fragment most often associated with canal occlusion and potential neurological compromise are not well described in a reproducible model. Methods Burst fractures were induced using a pendulum impact tester. The jig allowed for accurate positioning in all planes and for precise delivery of both the magnitude and vector of the impact force. This allowed for creation of fracture all three major groups of the AO classification. The A3 (burst fracture) was produced in 10 cadaveric sheep spines by delivering a neutral force vector on a physiologically flexed spine. The morphology of the fracture was confirmed by CT. Subsequent laminectomy was performed and the anatomical attachments of the large fragments were identified. Results The PLL was identified following laminectomy in each case. In six of the ten spines there had been significant disruption of the longitudinal structure of the PLL .In a further two cases there had been stripping of the PLL from the posterior aspect of the vertebral body in association with the retropulsed canal fragment. Subsequent excision of the PLL from the posterior aspects of vertebral body and discs did not compromise the attachment of the retropulsed fragment to the disc annulus in any case. Discussion This study confirms the anatomical relationship between disc fragment and disc annulus in the burst fracture setting. The strong attachment between fragment and disc facilitate rotation of the fragment about this hinge and into the canal. Subsequent intraoperative reduction of this fragment by restoration of disc height may require contribution both from this annular attachment and from tension set up in an intact PLL. The relative contributions of each of these structures in the reduction manoeuvre remains unclear

The purpose was to present a case of cauda equina entrapment in a lumbar burst fracture with associated lamina fracture and to review the literature and assess the appropriateness of current practices for cauda equina decompression. Reported incidence of cauda equina entrapment in the lamina fracture of lumbar burst fractures is 13–17%. Anterior surgery alone for decompressing the cauda equina in patients with lumbar burst fractures and associated lamina fractures will not always address the problem. We therefore suggest that posterior exploration may be the preferred approach if the aim of surgery is to decompress the neural elements

Aim of Study: (A) To study what causes Anterior Column Deficiency in Burst Fracture of Dorso Lumbar Spine in the acute and later phase. (B) To analyse radiologically, the significance of adjacent disc injuries in burst fracture of dorso lumbar spine. (C) To look into the effectiveness of posterior short segment stabilisation by pedicle screw fixation and fusion in these injuries, in relation to deformity and anterior column deficiency. Methods and Materials: Twenty consecutive cases of Superior Burst-split fracture of Dorsolumbar spine were studied prospectively. All cases underwent reduction, posterior short segment stabilisation by Steffee type pedicle screw fixation and two level posterolateral fusion. The average follow-up duration was 30.2 months. Standardised AP and lateral radiograph were taken pre-operatively and post-operatively at regular intervals (every three months). Radiological assessment using seven parameters (Vertebral body angle, Upper disc angle, Lower disc angle, Kyphotic angle, etc) were done from these radiographs. Result and Significance: The total average correction of kyphosis (in degree) at surgery was 21.5°, and the proportion of correction during surgery was – Upper disc 29% (6.3°), Vertebral body 68% (14.6°) and Lower disc 3% (0.6°). So 68% of the correction was at the vertebral body level and 32% at the adjacent discs levels. At follow-up, the total average loss of correction was 16.5°, and the proportion of loss at follow-up was – Upper disc 44% (7.2°), Vertebral body 14% (2.3°) and Lower disc 42% (7.0°). There was loss of 14.2° at the disc levels compared to 2.3° only at the vertebral body level. So 86% of the loss was at the adjacent disc levels. Conclusion: Distraction at the adjacent disc levels occurred at surgery while contouring the vertebral body using dorsal instrumentation. The distraction at the upper disc level was significant. Distraction at adjacent disc levels resulted in more anterior column deficiency. At follow-up, the loss in the vertebral body was minimal and most of the loss occurred at the adjacent disc levels. The anterior column deficiency caused by the injury to the adjacent disc is very major cause for failure of dorsal instrumentation than the deficiency caused by the vertebral body. The upper disc is more severely injured than the lower disc in the superior burst split fracture and so the degeneration is rapid in the upper disc and gradual in the lower disc. The CT cuts at the end plate levels of the vertebral body can help to judge roughly the extent of injury to the adjacent disc. Posterolateral fusion and late disc degeneration after consolidation of fusion result in collapse of the disc in kyphotic angulation, as it prevents collapse of posterior disc height

Spinal fractures are common following underbody blast. Most injuries occur at the thoracolumbar junction, and fracture patterns suggest the spine is flexed at the moment of injury. However, current mechanistic descriptions of vertebral fractures are based on low energy injuries, and there is no evidence to correlate fracture pattern with posture at the loading rates seen in blast injury. The T12-L1 segment of 4 human spines was dissected to preserve the paraspinal ligaments and potted in polymethylmecrylate. The specimens were impacted with a 14 kg mass at 3.5m/s in a drop tower; two specimens were impacted in neutral posture, one in flexion, and one in extension. A load cell measured the load history. CT scans and dissection identified the injury patterns. Each specimen sustained a burst fracture. The neutral specimens demonstrated superior burst fractures, the flexed specimen demonstrated a superior burst fracture with significant anterior involvement, and the extended specimen showed a posterior vertebral body burst fracture. At high loading rates, the posture of the spine at the moment of injury appears to affect the resulting fracture. This supports understanding the behaviour of the spine in blast injury and will allow improved mitigation system design in the future

Summary Statement. Burst fractures were simulated in vitro on human cadaveric spine segments. Displacement of the facet joints and pedicles were measured throughout the fracture process showing how these bony structures behave when an impact load is delivered. Introduction. Burst fractures account for almost 30% of all spinal injuries, which may result in severe neurological deficit, spinal instability and hence life impairment. 1. The onset of the fracture is usually traumatic, caused by a high-energy impact loading. Comminution of the endplates and vertebral body, retropulsion of fragments within the canal and increase of the intrapedicular distance are typical indicators of the injury. Experimental and numerical studies have reported strain concentration at the base of the pedicles, suggesting that the posterior processes play a fundamental role in the fracture initiation. 2,3. However, little is known about the dynamic behaviour of the vertebra undergoing an impact load. The aim of this study was to provide an in vitro cadaveric investigation on burst fracture, focusing on the widening of the facet joints and pedicles during the fracture development. Methods. Eight three-adjacent-vertebrae segments (T9-T10-T11, T12-L1-L2, L3-L4-L5) were harvested from three human spines preserving the ligaments and intervertebral discs. A testing frame was designed to hold the sample whilst undergoing an axial impact load (delivered through a drop-weight rig). Lateral displacement was recorded by two transducers (LVDT) sampled at 5000 Hz and data were used to calculate the percent maximum dynamic widening (MW) and percent residual widening after the impact (RW). LVDTs were positioned in contact with the most lateral region of the cranial facet joints where the central vertebra was lumbar; or posteriorly to the base of the pedicles for thoracic. Samples were divided into two groups to achieve two different grade of severity of the fracture by delivering two different amount of energy: High (HE) and Low (LE). Samples underwent HR-pQCT scanning prior and after fracturing to assess percent canal narrowing (CN), intrapedicular distance and grade the fracture. Differences between results were assessed using Mann-Whitney U test. Results. Burst fractures were induced in all the samples (fragment retropulsion was present in all HE samples). The median energy delivered to each group was 206J (HE) and 148J (LE) which led to a significant difference in the median CN (HE: 32.4%; LE: 11.8%; p=0.029). No significant difference was found between HE and LE in terms of MW (p=0.11), or RW (p=0.85). Furthermore, MW and CN were poorly correlated (R. 2. =0.13). In all the cases, the first peak in the widening data coincided with MW (median 12.8%, range 4.3–21.8%). RW measurements (median 2.8%, range −1.3–11.5%) were validated against HR-pQCT scans showing excellent agreement (R. 2. =0.93). Discussion/Conclusion. Results from this study provided further insight on the burst fracture process supporting the wedging effect of the adjacent facet joints when the impact load is transmitted. Indeed, the pedicles were forced to widen up to a critical value (MW), after which they fractured. Further experiments will help clarifying the influence of the amount of energy delivered

A predictive model for final kyphosis was tested by evaluating the radiographs of forty-three patients with traumatic burst fractures. Since clinical outcomes are related to final kyphosis in the ambulatory patient rather than on the initial supine injury radiograph, the ability to predict final kyphosis is beneficial in determining treatment. This study demonstrated that in the appropriately selected patient for conservative care, the limit of final-kyphosis(Kf) can be predicted from the intial-kyphosis(KI) , such that Kf= < KI+.5KI . Outliers from this equation were patients who had unrecognized posterior column fractures, superior and inferior end-plate fractures, and/or multiple level of injury. The purpose of this study was to define a prediction model that afforded clinicians the ability to define final kyphosis from initial supine films in order to guide the management of stable burst fractures. This study has demonstrated that as a rule of thumb, the final absolute kyphosis for stable burst fractures can be expected to be up to Ki (initial absolute kyphosis) + 1.5Ki. Outliers were found to be fractures with unrecognized posterior element injury, both superior and inferior endplate fractures and multiple level injuries. The final kyphosis is clinically more relevant than the initial kyphosis in terms of functional outcome after conservative management. A prediction model for final kyphosis based on initial injury films can help guide the clinician for optimal management. Retrospective radiographic analysis was performed on forty-three patients with a minimum follow up six months. All patients suffered traumatic burst fractures, which were deemed stable as to be satisfactorily managed in a brace. Serial radiographs were used to determine initial (Ki) and final (Kf), Kyphosis angles. Predicted Kf was determined using the equation Kf =Ki + 1.5 Ki. The initial absolute kyphosis was the measured kyphosis using the Cobb technique and including the loss of the expected normal lordosis of that spinal segment. Inclusion criteria included burst fractures at between levels T10 – L3 in the neurologically intact patient. The equation accurately predicted the final outcome , Kf, in 70 % of the cases. In 20% of the cases, the Kf was less than expected. (Acceptable clinical result). In 10% of the cases, Kf was greater than predicted or achieved a clinically unacceptable kyphotic angulation requiring secondary surgery. In this group of outliers, post-hoc analysis identified unrecognized posterior element injury, both superior and inferior endplate fractures and multiple level injuries. In traumatic burst fractures, the goal of management is to protect the spine during healing while maintaining an acceptable alignment, which will not lead to late pain and deformity. A final absolute kyphosis angle, Kf, from twenty to thirty degrees has been variably regarded as a threshold to obtain a good clinical outcome. Criteria for stability have been previously documented, however variables are based on initial presentation. Aside from careful classification of the fracture type, the current “rule of thumb” prediction model for Kf may further help the clinician with management decisions

Introduction: The management of patients with thoracolumbar burst fractures has evolved over the last 60 years from the days of conservative management through to the current era of anterior decompression combined with either anterior or posterior stabilisation. There is no doubt that surgical outcomes have improved markedly with the more modern techniques. Nevertheless, there are still technical and other difficulties, which the surgeon may encounter. Based upon his experience with posterior vertebrectomy and reconstruction for thoracolumbar tumours, the author has used this technique for the management of acute burst fractures in this region. This paper presents a review of 10 patients with severe thoracolumbar burst fracture or fracture dislocation managed since 1997, using a single stage posterior decompression, realignment and stabilisation/interbody fusion. Methods: Data were acquired prospectively on consecutive patients between June 1997 and October 2000. All patients underwent single stage posterior decompression via laminectomy and then a subtotal eggshell vertebrectomy with removal of any herniated bone fragment(s) or partial vertebrectomy/ pedicle subtraction osteotomy. Pedicle screw stabilisation was performed to include one or two vertebrae above and below the involved vertebra(e). The intervertebral discs adjacent to the fractured vertebra were removed prior to realigning the vertebral column and performing inter-body fusion using carbon fibre spacers and autograft (4 patients) or vertebral body reconstruction with Titanium mesh cages and autograft (6 patients). Results: The mean age was 37 years (21–52 years). There were six males and four females. Three patients had no neurological deficit. Seven had incomplete paraplegia, three of which were severe with no or only a flicker of leg movement. The principal fracture involved L1 in 6 patients, L2 in 2, L4 in 1 and L5 in 1. Seven had herniated bone fragments occupying 90+% of the spinal canal. Of the seven patients with incomplete paraplegia, all recovered the ability to walk. Two with conus lesions still self catheterize. There were no serious early complications. A serious late complication was the development at three months of a severe deep wound infection, which required debridement and subsequent anterior/ posterior revision surgery. One patient with severe polytrauma and an L4 burst fracture/dislocation has developed a chronic pain syndrome. Discussion: The decompression, realignment, interbody reconstruction and stabilisation of thoracolumbar burst fractures/dislocations using a single stage posterior technique is technically demanding but the neurological outcome and restoration of spinal balance in these 10 patients was gratifying. The procedure appears to have two advantages over an anterior decompression and reconstruction combined with anterior or posterior stabilisation: first, it appears to provide easier access and improved visualisation for lumbar burst fractures where the psoas muscle may be swollen and contused, and second, it allows for easier realignment of any coronal or sagittal deformity

Introduction: The aim of this study was to evaluate the efficacy of the treatment of vertebral burst fractures with kyphoplasty. This minimal-invasive technique has been established for the treatment of osteoporotic compression fractures. The value for the treatment of burst fractures is still under research. Materials and Methods: Between 2003 and 2006, 31 patients presenting a traumatic vertebral burst fracture Magerl Type A3 of the thoraco-lumbar junction were treated with balloon kyphoplasty. All had a normal neurological examination. Assessment of the patients outcome included subjective evaluation of pain (VAS), evaluation of the clinical function (Oswestry-Score), SF-36 Medical Outcome Survey and radiologic evaluation. Results: The patients experienced an early pain relief and early mobilisation. Complications such as constriction of the spinal channel were not observed. The morphology of the vertebral body showed minor correction of the malposition. Conclusion: Kyphoplasty represents an efficient and minimal-invasive alternative for the treatment of burst fractures of the thoraco-lumbar junction. This technique allows an early return to daily activities with almost pain relief and with a low incidence of complications

Anterior only procedure for stable thoraco-lumbar burst fractures is controversial. Prospective collection of clinical and radiological data in stable burst fractures with neurological deficit undergoing anterior only decompression and stabilisation with 2-year follow-up. 14 consecutive patients (8 females, 6 males) with two-column thoracolumbar burst fracture and neurological deficit underwent anterior corpectomy/hemi-corpectomy and instrumentation, from February 2007 to February 2009. Radiological data included classification of fracture (AO classification), kyphus angle and degree of canal compromise. Post-operative CT scans done to assess radiological improvement. Clinical data included neurological deficit at presentation, improvement or changes in neurology, length of surgery, estimated blood loss, post-operative complications and length of stay. Commonest mechanism was fall from height. 10 patients had incomplete burst fractures amenable to hemi-corpectomy. 8 of our patients were ASIA D, 4 were ASIA C or lower. They all improved by at least one grade. 2 patients had identical ASIA grade pre and post operatively. Pre-operative spinal canal compromise averaged 52.6% and vertebral body height loss averaged 48.9%. The mean kyphotic angles improved from 19.6° to 7.9 °. There were two cases with minor injury to the diaphragm, one developing a pneumothorax. Mean length of surgery and hospital stay were 4hours and 21minutes and 11.8 days respectively. The fractures in which the top part is burst and causing canal compromise, could be dealt with by top hemi-corpectomy requiring smaller approach. One stage anterior – only stabilization can yield successful clinical results

Introduction: Spinal cord injury (SCI) continues to challenge the healthcare and the adjunct social welfare systems. Significant advances have been made in our understanding of the pathological cascade following the initial insult. However, this has yet to be translated into clinically significant treatments and one possible reason for this is that little is known about the actual interaction between the cord and the spinal column at the moment of impact; a factor that is becoming increasingly recognised as important. Burst fractures are a common cause of SCI and are sufficiently well defined to allow significant advances to be made in developing laboratory models of the fracture process. Following on from these advances an in-vitro model of the interaction between the cord and burst fracture fragment was developed and used to perform preliminary experiments to establish those factors that are important in determining the extent of probable cord damage. Methods: A rig was developed that reliably reproduced a range of fragment-cord impact scenarios previously observed in the development of a model of the burst fracture process. In summary, a simulated bone fragment of mass 7.2 g was fired, transversely, at explanted bovine cord (within 3 hours of slaughter) with a velocity of 2.5, 5.0 or 7.5 ms-1. The cords were mounted in a tensile testing machine using a novel clamping system and held at 8 % strain. A surrogate posterior longitudinal ligament (PLL) was included and simulated in three biomechanically relevant conditions: absent, 0 % strain and 14 % strain. The posterior elements were represented by an anatomically correct surrogate. The impacts were recorded by using either a high speed video camera (4500 frames/s) or a series of fine pressure transducers. Results: The fragments were recorded to undergo the same occlusion profile as previously reported in the burst fracture model, except that the cord itself reduced the level of maximum occlusion possible. All tests displayed the fragment recoiling following maximum occlusion. The maximum occlusion and the time to this position were found to be significantly dependent on both the fragment velocity and the condition of the PLL. Similar results were observed for peak pressure. One surprising result was that maximum occlusion or time to this event did not change with or without the cord being encased in the dura mater; a structure that is thought to protect the cord from external impacts. Discussion: The model developed here of the cord-column interaction for the burst fracture produced useful initial insights into the factors that affect the impact on the cord. The PLL has a significant role to play in both reducing the peak pressures and the spreading the energy imparted over a longer period. The model has several areas in which it could be improved and these include 1) the incorporation of the perfusion pressure which tends to hydraulically stiffen the cord and 2) the inclusion of the cerebrospinal fluid, which may operate in unison with the dura in protecting the cord from impacts. Future work includes the incorporation of the CSF into the model, the development of surrogate cords and the generation of computational models using novel programming techniques

Decision-making regarding operative versus non-operative treatment of patients with thoracolumbar burst fractures in the absence of neurological deficits is controversial, and evidence from trials is sparse. We present a systematic review and meta-analysis of randomised trials comparing operative treatment to non-operative treatment in the management of thoracolumbar burst fractures. With the assistance of a medical librarian, an electronic search of Medline Embase and Cochrane Central Register of Controlled trials was performed. Trials were included if they: were randomided, had radiologically confirmed thoracolumbar (T10-L3) burst fractures, had no neurological deficit, compared operative and non-operative management (regardless of modality used), and had participants aged 18 and over. We examined the following outcomes: pain, using a visual analogue scale (VAS), where 0=no pain and 100=worst pain; function, using the validated Roland Morris Disability Questionnaire (RMDQ); and Kyphosis (measured in degrees). Two randomised trials including 79 patients (41 operative vs. 38 non-operative) were identified. Both trials had similar quality, patient characteristics, outcome measures, rates of follow up, and times of follow up (mean=47 months). Individual patient data meta-analysis (a powerful method of meta-analysis) was performed, since data was made available by the authors. There were no between-group differences in sex, level of fracture, mechanism of injury, follow up rates or baseline pain, kyphosis and RMDQ scores, but there was a borderline difference in age (mean 44 years in operative group vs. 39 in non-operative group, p=0.046). At final follow up, there were no between group differences in VAS pain (25 in operative group vs. 22 non-operative, p=0.63), RMDQ scores (6.1 in operative group vs. 5.8 non-operative, p=0.85), or change in RMDQ scores from baseline (4.8 in operative group vs. 5.3 non-operative, p=0.70). But both kyphosis at final follow up (11 degrees vs. 16 degrees, p=0.009) and reduction in kyphosis from baseline (1.8 degrees vs. -3.3 degrees, p=0.003) were better in the operative group. Operative management of thoracolumbar burst fractures appears to improve kyphosis, but does not improve pain or function

The progressive kyphosis and pain in patients with acute thoracolumbar burst fractures treated conservatively so as the recurrent kyphosis after posterior reduction and fixation were associated to disc collapse rather than vertebral body compression. It depends on redistribution of the disc tissue in the changed morphology of the space after fractures of the endplate. The aim of this study is to evaluate the safety and the efficacy of balloon kyphoplasty with calcium phosphate, alone or associated to short posterior instrumentation, in the treatment of acute thoracolumbar burst fractures. Eleven fractures in ten consecutive patients with an average age of 48 years who sustained acute thoracolumbar traumatic burst fractures without neurological deficits were included in this study. The fractures were A1.2 (3), A3.1 (4) and A3.2 (4), according to AO classification. In 7 fractures (A1.2 and A3.1) the kyphopasty was performed alone in order to make the most of efficacy in fracture reduction, anterior and medium column stabilization and, as much as possible, segmental kyphosis correction. In the A3.2 fractures (4), that are unstable, the kyphoplasty was associated to a short posterior instrumentation. To avoid the PMMA long run complications in younger patients, we used a calcium phosphate cement. VAS, SF-36, Roland-Morris questionnaire (RMQ) and Oswestry low back pain disability questionnaire (ODQ) were used to evaluate pain, state of health, functional outcomes and spine disability. To the average follow-up time of 15.5 months (range 8–31) we did not observe statistically significant differences in 7 of 8 SF-36 domains in comparison to general healthy population of same sex and age. At the same follow-up, the spine disability questionnaire showed a functional restriction of 18% (ODQ) and 29,6% (RMQ) being 100% the maximum of disability. No bone cement leakage, no implant failure and no height correction loss were observed in any case. Our data confirm the safety and the efficacy of ballon kyphoplasty with calcium phosphate in the treatment of acute thoracolumbar burst fractures. In this way we can reduce the possible complications resulted from discal space collapse and obtain an early functional restoration. When performed alone, this mini invasive surgical technique offer the advantage of almost immediate return to daily activities. When associated to posterior instrumentation, it decreases the long run complications and allows to reduce the number of stabilized levels, maintaining, in part, the thoracolumbar junction movement

Controversy exists as to whether burst fractures without neurological deficit should be treated operatively or non operatively. We assessed the functional outcomes of non operative treatment of burst fractures using the Oswestry disability index (ODI). 57 Patients who were treated non operatively (bed rest for one week and a corset for 3 months) were assessed using the Oswestry disability index (ODI) over a 6 month period. Assessments were done at an average of 4.8 years (range 18 months–7 years) post injury. There were 37 males and 22 females with an average age of 39 years. Fifty-three percent (31) injuries were due to a fall and twenty-two percent (22) followed an MVA. 90% Of fractures occurred between T12 and L2. Plain x-rays and CT scans were obtained to evaluate the burst fracture. The initial average Cobb angle was nineteen degrees (19. 0. ) (range 6. 0. –53. 0. ) with an average progression in Cobb angle was 7. 0. and the average final Cobb angle was 26. 0. (9. 0. –71. 0. ) The average ODI was 17.32% (range 0 48%). Personal care, sexual activity and sleeping were not significantly affected (ODI : 0 or 1 each). Fifty-five percent (11/20) who were previously unemployed returned to work and none of those patients who were previously unemployed, were employed at a later date. All 11 housewives experienced no difficulty with household chores. This study revealed that 31 patients occasionally used analgesia (paracetamol). The authors conclude that non operative treatment of burst fractures is a viable option in neurologically intact patients

The exact mechanism of remodelling of burst fractures is uncertain. We studied the relationship between epidural pressures and remodelling. In a prospective, ethically-approved study in 34 patients with burst fractures at the levels T12 to L4, epidural pressure was measured. Four patients were lost to follow-up. In 18 patients the fractures were due to a fall and in 12 to motor vehicle accidents. The mean age was 37 years. All patients were neurologically intact and treated non-operatively. Plain radiographs and CT scans measuring the sagittal plane deformity and mid-sagittal diameter respectively were obtained. Using a fluoroscopically-guided radio-opaque catheter placed at the normal interspace below the burst fracture, epidural pressure was measured at 2 weeks and at 12 months after the injury. The mean canal compromise shown on CT scan at the time of injury and at follow-up was 43% (32% to 83%) and 28% (44% to 100%) respectively. CT volumetric measurements showed a mean improvement of 10% at follow-up (7% to 16%). The epidural pressures recorded at the time of injury and at follow-up were 16.65 mmHg (2.5 to 30.85) and 5.85mmHg (0 to 10.17) respectively. At 1-year follow-up, the Cobbs angle had progressed by a mean of 2.69° (10° to 60°). The retropulsed burst fracture fragments cause localised constriction of the spinal cord (Venturi effect). Epidural pressure, raised to maintain a constant flow rate across this constriction, has a mechanical effect on the retropulsed fragments, thus promoting remodelling