Aims. The outcome following the development of neurological complications after corrective surgery for scoliosis varies from full recovery to a permanent deficit. This study aimed to assess the prognosis and recovery of major neurological deficits in these patients, and to determine the risk factors for non-recovery, at a minimum follow-up of two years. Methods. A major neurological deficit was identified in 65 of 8,870 patients who underwent corrective surgery for scoliosis, including eight with complete paraplegia and 57 with incomplete paraplegia. There were 23 male and 42 female patients. Their mean age was 25.0 years (SD 16.3). The aetiology of the scoliosis was idiopathic (n = 6), congenital (n = 23), neuromuscular (n = 11), neurofibromatosis type 1 (n = 6), and others (n = 19). Neurological function was determined by the American Spinal Injury Association (ASIA) impairment scale at a mean follow-up of 45.4 months (SD 17.2). the patients were divided into those with recovery and those with no recovery according to the ASIA scale during follow-up. Results. The incidence of major deficit was 0.73%. At six-month follow-up, 39 patients (60%) had complete recovery and ten (15.4%) had incomplete recovery; these percentages improved to 70.8% (46) and 16.9% (11) at follow-up of two years, respectively. Eight patients showed no recovery at the final follow-up. The cause of injury was mechanical in 39 patients and ischaemic in five. For 11 patients with misplaced implants and haematoma formation, nine had complete recovery. Fisher’s exact test showed a significant difference in the aetiology of the scoliosis (p = 0.007) and preoperative deficit (p = 0.016) between the recovery and non-recovery groups. A preoperative deficit was found to be significantly associated with non-recovery (odds ratio 8.5 (95% confidence interval 1.676 to 43.109); p = 0.010) in a multivariate regression model. Conclusion. For patients with scoliosis who develop a major neurological deficit after corrective surgery, recovery (complete and incomplete) can be expected in 87.7%. The first three to six months is the time window for recovery. In patients with misplaced implants and haematoma formation, the prognosis is satisfactory with appropriate early intervention. Patients with a preoperative neurological deficit are at a significant risk of having a permanent deficit. Cite this article: Bone Joint J 2022;104-B(1):103–111

Aims

The aim of this study was to reassess the rate of neurological, psoas-related, and abdominal complications associated with L4-L5 lateral lumbar interbody fusion (LLIF) undertaken using a standardized preoperative assessment and surgical technique.

Objectives. To employ a simple and fast method to evaluate those patients with neurological deficits and misplaced screws in relatively safe lumbosacral spine, and to determine if it is necessary to undertake revision surgery. Methods. A total of 316 patients were treated by fixation of lumbar and lumbosacral transpedicle screws at our institution from January 2011 to December 2012. We designed the criteria for post-operative revision scores of pedicle screw malpositioning (PRSPSM) in the lumbosacral canal. We recommend the revision of the misplaced pedicle screw in patients with PRSPSM = 5′ as early as possible. However, patients with PRSPSM < 5′ need to follow the next consecutive assessment procedures. A total of 15 patients were included according to at least three-stage follow-up. Results. Five patients with neurological complications (PRSPSM = 5′) underwent revision surgery at an early stage. The other ten patients with PRSPSM < 5′ were treated by conservative methods for seven days. At three-month follow-up, only one patient showed delayed onset of neurological complications (PRSPSM 7′) while refusing revision. Seven months later, PRSPSM decreased to 3′ with complete rehabilitation. Conclusions. This study highlights the significance of consecutively dynamic assessments of PRSPSMs, which are unlike previous implementations based on purely anatomical assessment or early onset of neurological deficits.and also confirms our hypothesis that patients with early neurological complications may not need revision procedures in the relatively broad margin of the lumbosacral canal. Cite this article: X-J. Lin. Treatment strategies for early neurological deficits related to malpositioned pedicle screws in the lumbosacral canal: A pilot study. Bone Joint Res 2016;5:46–51

The aim of this study was to compare the treatment ouctomes of severe idiopathic scoliosis (IS) (>90 degrees) using the staged surgery with initial limited internal distraction and typical IS treated using segmental pedicle screw instrumentation. We hypothesized that staged surgical treatment of severe scoliosis would improve more HRQoL and pulmonary function (PF) as compared with posterior spinal fusion (PSF) for typical IS curves. It was a retrospective review of a consecutive series of 60 IS, severe group (SG) vs. moderate group (MG) with min. 2 years of follow up (FU). The mean preoperative major curve (MC) was 120° and thoracic kyphosis (TK) was 80° for the SG and 54° and 17° for the MG, respectively (p<0.001). The MC was corrected to 58° and TK to 32° for the SG; the MC to 26° and TK to 14°, for the MG, respectively (p<0.001). The mean preoperative AVT was 8.9 cm and improved to 2.8 cm at the final FU for the SG and from 6.5 cm to 2.2 cm at the final FU for the MG (p<0.001). At baseline, the FVC% & FEV1% values were significant different between the two groups (41.5% vs. 83%, p <0.001) & (41.6% vs. 77%, p <0.001). Compared the baseline for SG vs. the values at 2-year FU the FVC % values were (41.5% vs. 66.5%, p <0.001), and the baseline for MG vs. the values at 2-year FU, the FEV1 values were (77% vs. 81%, NS). At last FU, no complications were reported. Gradual traction with complicity of multilevel Ponte's osteotomies and neuromonitoring followed by staged pedicle screws instrumentation in severe IS proved to be a safe and effective method improving spinal deformity (52% correction), PF (improved percentage of predicted forced vital capacity by 49%), and health-related quality and allows to achieve progressive curve correction with no neurologic complications associated to more aggressive one-stage surgeries

Aims

A variety of surgical methods and strategies have been demonstrated for Andersson lesion (AL) therapy. In 2011, we proposed and identified the feasibility of stabilizing the spine without curettaging the vertebral or discovertebral lesion to cure non-kyphotic AL. Additionally, due to the excellent reunion ability of ankylosing spondylitis, we further came up with minimally invasive spinal surgery (MIS) to avoid the need for both bone graft and lesion curettage in AL surgery. However, there is a paucity of research into the comparison between open spinal fusion (OSF) and early MIS in the treatment of AL. The purpose of this study was to investigate and compare the clinical outcomes and radiological evaluation of our early MIS approach and OSF for AL.

Aims. We present the results of correcting a double or triple curve adolescent idiopathic scoliosis using a convex segmental pedicle screw technique. Patients and Methods. We reviewed 191 patients with a mean age at surgery of 15 years (11 to 23.3). Pedicle screws were placed at the convexity of each curve. Concave screws were inserted at one or two cephalad levels and two caudal levels. The mean operating time was 183 minutes (132 to 276) and the mean blood loss 0.22% of the total blood volume (0.08% to 0.4%). Multimodal monitoring remained stable throughout the operation. The mean hospital stay was 6.8 days (5 to 15). Results. The mean post-operative follow-up was 5.8 years (2.5 to 9.5). There were no neurological complications, deep wound infection, obvious nonunion or need for revision surgery. Upper thoracic scoliosis was corrected by a mean 68.2% (38% to 48%, p < 0.001). Main thoracic scoliosis was corrected by a mean 71% (43.5% to 8.9%, p < 0.001). Lumbar scoliosis was corrected by a mean 72.3% (41% to 90%, p < 0.001). No patient lost more than 3° of correction at follow-up. The thoracic kyphosis improved by 13.1° (-21° to 49°, p < 0.001); the lumbar lordosis remained unchanged (p = 0.58). Coronal imbalance was corrected by a mean 98% (0% to 100%, p < 0.001). Sagittal imbalance was corrected by a mean 96% (20% to 100%, p < 0.001). The Scoliosis Research Society Outcomes Questionnaire score improved from a mean 3.6 to 4.6 (2.4 to 4, p < 0.001); patient satisfaction was a mean 4.9 (4.8 to 5). . Conclusions. This technique carries low neurological and vascular risks because the screws are placed in the pedicles of the convex side of the curve, away from the spinal cord, cauda equina and the aorta. A low implant density (pedicle screw density 1.2, when a density of 2 represents placement of pedicle screws bilaterally at every instrumented segment) achieved satisfactory correction of the scoliosis, an improved thoracic kyphosis and normal global sagittal balance. Both patient satisfaction and functional outcomes were excellent. Cite this article: Bone Joint J 2017;99-B:1080–7

This review of the literature presents the current understanding of Scheuermann’s kyphosis and investigates the controversies concerning conservative and surgical treatment. There is considerable debate regarding the pathogenesis, natural history and treatment of this condition. A benign prognosis with settling of symptoms and stabilisation of the deformity at skeletal maturity is expected in most patients. Observation and programmes of exercise are appropriate for mild, flexible, non-progressive deformities. Bracing is indicated for a moderate deformity which spans several levels and retains flexibility in motivated patients who have significant remaining spinal growth. The loss of some correction after the completion of bracing with recurrent anterior vertebral wedging has been reported in approximately one-third of patients. Surgical correction with instrumented spinal fusion is indicated for a severe kyphosis which carries a risk of progression beyond the end of growth causing cosmetic deformity, back pain and neurological complications. There is no consensus on the effectiveness of different techniques and types of instrumentation. Techniques include posterior-only and combined anteroposterior spinal fusion with or without posterior osteotomies across the apex of the deformity. Current instrumented techniques include hybrid and all-pedicle screw constructs

Segmental vessel ligation during anterior spinal surgery has been associated with paraplegia. However, the incidence and risk factors for this devastating complication are debated. We reviewed 346 consecutive paediatric and adolescent patients ranging in age from three to 18 years who underwent surgery for anterior spinal deformity through a thoracic or thoracoabdominal approach, during which 2651 segmental vessels were ligated. There were 173 patients with idiopathic scoliosis, 80 with congenital scoliosis or kyphosis, 43 with neuromuscular and 31 with syndromic scoliosis, 12 with a scoliosis associated with intraspinal abnormalities, and seven with a kyphosis. There was only one neurological complication, which occurred in a patient with a 127° congenital thoracic scoliosis due to a unilateral unsegmented bar with contralateral hemivertebrae at the same level associated with a thoracic diastematomyelia and tethered cord. This patient was operated upon early in the series, when intra-operative spinal cord monitoring was not available. Intra-operative spinal cord monitoring with the use of somatosensory evoked potentials alone or with motor evoked potentials was performed in 331 patients. This showed no evidence of signal change after ligation of the segmental vessels. In our experience, unilateral segmental vessel ligation carries no risk of neurological damage to the spinal cord unless performed in patients with complex congenital spinal deformities occurring primarily in the thoracic spine and associated with intraspinal anomalies at the same level, where the vascular supply to the cord may be abnormal

Aims

Closed suction subfascial drainage is widely used after instrumented posterior spinal fusion in patients with a spinal deformity. The aim of this study was to determine the effect of this wound drainage on the outcomes in patients with adolescent idiopathic scoliosis (AIS). This was a further analysis of a randomized, multicentre clinical trial reporting on patients after posterior spinal fusion using segmental pedicle screw instrumentation. In this study the incidence of deep surgical site infection (SSI) and chronic postoperative pain at two years’ follow-up are reported.

Aims

The aim of this study was to compare outcomes after growth-friendly treatment for early-onset scoliosis (EOS) between patients with skeletal dysplasias versus those with other syndromes.

Aims. The primary aim of this study was to evaluate the performance and safety of magnetically controlled growth rods in the treatment of early onset scoliosis. Secondary aims were to evaluate the clinical outcome, the rate of further surgery, the rate of complications, and the durability of correction. Patients and Methods. We undertook an observational prospective cohort study of children with early onset scoliosis, who were recruited over a one-year period and followed up for a minimum of two years. Magnetically controlled rods were introduced in a standardized manner with distractions performed three-monthly thereafter. Adverse events which were both related and unrelated to the device were recorded. Ten children, for whom relevant key data points (such as demographic information, growth parameters, Cobb angles, and functional outcomes) were available, were recruited and followed up over the period of the study. There were five boys and five girls. Their mean age was 6.2 years (2.5 to 10). Results. The mean coronal Cobb angle improved from 57.6° (40° to 81°) preoperatively, 32.8° (28° to 46°) postoperatively, and 41° (19° to 57°) at two years. Five children had an adverse event, with four requiring return to theatre, but none were related to the device. There were no neurological complications or infections. No devices failed. One child developed a proximal junctional kyphosis. The mean gain in spinal column height from T1 to S1 was 45.4 mm (24 to 81) over the period of the study. Conclusion. Magnetically controlled growth rods provide an alternative solution to traditional growing rods in the surgical management of children with early onset scoliosis, supporting growth of the spine while controlling curve progression. Their use has clear psychosocial and economic benefits, with the reduction of the need for repeat surgery as required with traditional growing rods. Cite this article: Bone Joint J 2018;100-B:507–15

Aims. We aimed to retrospectively assess the accuracy and safety of CT navigated pedicle screws and to compare accuracy in the cervical and thoracic spine (C2-T8) with (COMB) and without (POST) prior anterior surgery (anterior cervical discectomy or corpectomy and fusion with ventral plating: ACDF/ACCF). Patients and Methods. A total of 592 pedicle screws, which were used in 107 consecutively operated patients (210 COMB, 382 POST), were analysed. The accuracy of positioning was determined according to the classification of Gertzbein and Robbins on post-operative CT scans. Results. High accuracy was achieved in 524 screws (88.5%), 192 (87.7%) in the cervical spine and 332 (89%) in the thoracic spine, respectively. The results in the two surgical groups were compared and a logistic regression mixed model was performed to analyse the risk of low accuracy. Significantly lower accuracy was found in the COMB group with 82.9% versus 91.6% in the POST group (p = 0.036). There were no neurological complications, but two vertebral artery lesions were recorded. Three patients underwent revision surgery for malpositioning of a screw. Although the risk of malpositioning of a screw after primary anterior surgery was estimated to be 2.4-times higher than with posterior surgery alone, the overall rates of complication and revision were low. Conclusion. We therefore conclude that CT navigated pedicle screws can be positioned safely although greater caution must be taken in patients who have previously undergone anterior surgery. Cite this article: Bone Joint J 2017;99-B:1373–80

Objective. The use of all pedicle screw constructs for the management of spinal deformities has gained widespread popularity. However, the placement of pedicle screws in the deformed spine poses unique challenges for the spinal surgeon. The purpose of this study was to evaluate the complications and radiological outcomes of surgery in 124 consecutive patients with spinal deformity. These patients underwent correction of coronal and sagittal imbalance with segmental pedicle screw fixation only. Background. All pedicle screw constructs have been associated with improved correction in all three planes. In patients with severe deformity, such constructs can obviate the need for anterior surgeries, and the higher implant cost is offset by the avoidance of dual anterior and posterior approaches. Pedicle screw fixation enables enhanced correction of spinal deformities, but the technique is still not widely applied for thoracic deformities for fear of neurological complications. This is a retrospective study that was carried out on 124 patients who underwent segmental screw fixation for coronal and sagittal spinal deformities. The purpose of this study was to evaluate the complications and outcomes of this technique and also assess the evidence of enhanced correction. Material and Methods. A total of 124 consecutive patients subjected to pedicle screw fixation for spinal deformities were analysed after a minimum period of follow-up of two years. Etiologic diagnoses were idiopathic scoliosis in 32, neuromuscular scoliosis 48, Scheuermann's kyphosis in 28 and others 16. They were reviewed using the medical records and preoperative, intraoperative and postoperative radiographs. Computed tomography was performed when screw position was questionable. Deformity correction was determined on preoperative and postoperative radiographs. The positions of the screws were evaluated using intraoperative and postoperative radiographs. There were 51 male and 73 female patients with the mean age of 17.2 years (range, 10-25 years). The average cobb angle for scoliosis and kyphosis were 55°(range 45°-85°) and 72° (range 68°-100°) respectively. Results. A total of 2784 pedicle screws were inserted and 1488 screws were inserted in the thoracic spine (18 screws/patient). Screw-related neurological complications occurred in two patients 0.4%; these comprised a transient paraparesis and dural tear. Other complications comprised six intraoperative pedicle fractures, 12 screw loosening, four postoperative infections and one haemothorax. There were no significant screw-related neurological or visceral complications. The average correction was 78% for scoliosis and 51% for kyphosis. The mean estimated blood loss was 653 ml (range, 510-850), the mean operation time was 148 minutes (range, 120-220). Conclusion. We were able to demonstrate that application of pedicle screw construct is safe and advantageous in the management of spinal deformities. Significant correction has been achieved with a single stage posterior surgery in all groups. Scoliosis and kyphotic deformity corrections were 78% and 51% respectively; this is far superior to correction achieved with one stage surgery with other constructs. This study showed that improved derotation has decreased the need for thoracoplasty, thus eliminating its risk of associated morbidity. Superior control of the deformity obviated the need for an anterior approach in severe curves. Improved correction, lower morbidity and shorter hospitalisation has compensated for higher implant cost. We believe using all pedicle screw fixation is a relatively safe procedure and offers an excellent correction. This correction was maintained throughout the follow up period. Despite our safety record in thoracic pedicle screw placement, we believe this technique can be potentially dangerous in inexperienced hands, and requires a long learning curve. Therefore, a thorough anatomical knowledge of pedicle morphology, a detailed analysis of pre-operative imaging coupled with experience is essential to avoid complications. Ethics approval None. Interest Statement None

The current trend in kyphosis correction is for “every level” instrumentation to achieve intraoperative stability, correction, fusion and implant longevity. We evaluate the medium term follow up of a low implant density (LID) construct. All patients with adolescent kyphosis (idiopathic or Scheurmann's) on our deformity database were identified. Radiographs and records were analysed for neurological complications, correction and revision. The constructs included were all pedicle screw anchors with multiple apical chevron osteotomies and a proximal and distal “box” of 6 to 8 screws. A four rod cantilever reduction manoeuvre with side to side connectors completed the construct. Kyphosis for any other cause was excluded. Follow up less than 12 months was excluded. 23 patients were identified with an average follow up 27 months (72 to 12 months) and a mean implant density of 1.1 (53.5% of “available” pedicles instrumented). There was 1 false positive neurophysiological event without sequelae (4%). There were no proximal junctional failures (0%). There were no pseudarthroses or rod breakages (0%). There was 1 loss of distal rod capture (early set screw failure) (4%). This was revised uneventfully. There were 4 infections requiring debridement (early series). Average initial correction was 44% (77.7 degrees to 43.5 degrees) with a 1% loss of correction at final follow up (43.5 to 44.0 degrees). The fulcrum bending correction index was 107% (based on fulcrum extension radiographs). 85% of curves had a fulcrum flexibility of less than 50%. The average cost saving compared to “every level “instrumentation was £5700 per case. This paper shows that a LID construct for kyphosis has technical outcomes as good as high density constructs. The obvious limitation of the study is the small number of patients in the cohort. The infection rates have improved with changes to perioperative process in the later series of patients. We do not believe these are a consequence of the construct itself

Aims. To describe the clinical, radiological, and functional outcomes in patients with isolated congenital thoracolumbar kyphosis who were treated with three-column osteotomy by posterior-only approach. Methods. Hospital records of 27 patients with isolated congenital thoracolumbar kyphosis undergoing surgery at a single centre were retrospectively analyzed. All patients underwent deformity correction which involved a three-column osteotomy by single-stage posterior-only approach. Radiological parameters (local kyphosis angle (KA), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic tilt (PT), sacral slope (SS), C7 sagittal vertical axis (C7 SVA), T1 slope, and pelvic incidence minus lumbar lordosis (PI-LL)), functional scores, and clinical details of complications were recorded. Results. The mean age of the study population was 13.9 years (SD 6.4). The apex of deformity was in thoracic, thoracolumbar, and lumbar spine in five, 14, and eight patients, respectively. The mean operating time was 178.4 minutes (SD 38.5) and the mean operative blood loss was 701.8 ml (SD 194.4). KA (preoperative mean 70.8° (SD 21.6°) vs final follow-up mean 24.7° (SD 18.9°); p < 0.001) and TK (preoperative mean -1.48° (SD 41.23°) vs final follow-up mean 24.28° (SD 17.29°); p = 0.005) underwent a significant change with surgery. Mean Scoliosis Research Society (SRS-22r) score improved after surgical correction (preoperative mean 3.24 (SD 0.37) vs final follow-up mean 4.28 (SD 0.47); p < 0.001) with maximum improvement in self-image and mental health domains. The overall complication rate was 26%, including two neurological and five non-neurological complications. Permanent neurological deficit was noted in one patient. Conclusion. Deformity correction employing three-column osteotomies by a single-stage posterior-only approach is safe and effective in treating isolated congenital thoracolumbar kyphosis. Cite this article: Bone Joint J 2021;103-B(7):1309–1316

Aims

To determine the value of scoliosis surgery, it is necessary to evaluate outcomes in domains that matter to patients. Since randomized trials on adolescent idiopathic scoliosis (AIS) are scarce, prospective cohort studies with comparable outcome measures are important. To enhance comparison, a core set of patient-related outcome measures is available. The aim of this study was to evaluate the outcomes of AIS fusion surgery at two-year follow-up using the core outcomes set.

Consecutive case series. To evaluate the efficacy of a strict stepwise radioanatomical procedure protocol in avoiding neurological complications through tool malplacement in fluoroscopy guided percutaneous procedures of the thoracic spine. Fluoroscopy guided percutaneous access to thoracic vertebral bodies is technically demanding. There is a trend towards computed tomography (CT) guidance on grounds of perceived lesser risk of spinal canal instrument malplacement. CT is however not always readily accessible and a safe technique for fluoroscopy guided procedures therefore desirable. 350 consecutive fluoroscopy guided percutaneous procedures (biopsy, vertebroplasty or kyphoplasty) covering all thoracic vertebral levels T1-T12 were performed according to a strict stepwise radioanatomical protocol. The crucial step of the protocol was not to advance the tool beyond the anterior-posterior (ap) projection of the medial pedicle wall until the tip of the instrument had been verified to have reached the posterior vertebral cortex in the lateral projection. The neurological status of patients was assessed through clinical examination prior to, immediately after the procedure and before discharge. Percutaneous instrument placement in the targeted thoracic vertebral body was achieved in all cases and the stepwise radioanatomical protocol was followed in all cases. There was no case of neurological deterioration in the case series. Conclusion: Attention to radiographic landmarks, specifically not crossing the ap projection of the medial pedicle cortex prior to reaching the posterior vertebral wall in the lateral projection, allows neurologically safe performance of fluoroscopy guided percutaneous procedures of the thoracic spine. This simple protocol is particularly useful when access to CT is limited

STUDY DESIGN. Retrospective study of 8 children treated with vertical expandable prosthetic titanium rib (VEPTR) for correction of early onset spinal scoliotic deformities. METHODS. 8 children with progressive scoliosis due to a variety of conditions, 6 congenital (2 Goldenhar syndrome, 2 VACTERL syndrome, 2 congenital thoracic abnormalities), 1 spondyloepiphyseal dysplasia, 1 early onset of scoliosis, underwent the index procedure and subsequent lengthening procedures at 6 months intervals (1 patient had 11 lengthening procedures). Mean age was 4 years (2-6 years) and mean follow up 3.8 years (2-6 years). Mean preoperative Cobb angle was 64,8° (51-108) and mean postoperative angle 40° (31-50). RESULTS. There were no neurological complications. Three patients developed infection with wound breakdown. One patient underwent removal of one of the two VEPTR rods. In the other two patients the rods were removed followed by antibiotics and the VEPTR converted to another growing rod system. Overall, patients tolerated the multiple procedures well. Three patients experienced significant distress with multiple surgical procedures. CONCLUSION. VEPTR offers a viable treatment option for children with severe congenital and early onset scoliosis where there are no viable alternatives. It achieves and maintains spinal deformity correction, while allowing for continued spine and chest-wall growth. Complication rate is acceptable in view of the benefits. None of the complications have lead to long term complications to date, but the repeated lengthening have resulted in psychological disturbance which we are investigating further. An implantable driver would offer very significant advantages and would avoid some of the repeated operations

Aim:. To present the results of multi-modal IOM in 298 patients who underwent spinal deformity correction. Method:. We reviewed the notes, surgical and IOM charts of all patients who underwent spinal surgery with the use of cortical and cervical SSEPs, as well as upper/lower limb transcranial electrical MEPs under the senior author. We recorded IOM events which we categorised as true, transient true and false (+) or (−). We correlated the IOM events with surgical or anaesthetic incidents. Results:. Diagnosis included idiopathic scoliosis in 224, congenital in 12, syndromic in 14, scoliosis with intraspinal anomaly in 5, scoliosis with congenital cardiac disease in 4, spondylolisthesis in 2, spinal tumour in one, and Scheuermann's kyphosis in 36 patients. We identified 3 true (+) monitoring events occurring in 2 patients (1%), 6 transient true (+) (2%), and 11 transient false (+) events (3.7%). True (+) events occurred during deformity correction in one patient with severe AIS and during osteotomies in another with severe Scheuermann's. Transient true (+) events occurred during posterior osteotomies in 2 patients with Scheuermann's, during scoliosis correction (apical correction with sublaminar wires) in one and placement of concave apical pedicle screw in another patient, and 2 IOM changes during positioning (one during reduction of spondylolisthesis-one during positioning on the surgical table). Transient false (+) events were mainly related to low blood pressure (10 patients). There were no false (−) IOM events and none of our patients had postoperative neurological complications. Sensitivity of our IOM technique was 100% [all patients with impending spinal cord injury will have a (+) event] and specificity 96% (patients with normal IOM had 96% chance that the cord was safe). Positive predictive value was 65.3% (65.3% chance that an IOM event reflected a surgical-related cause of cord injury); negative predictive value 100% (100% chance that normal IOM corresponded to no cord injury). We found no difference between patients with AIS and Scheuermann's in terms of risk of true or transient true (+) IOM events (Fisher's exact test, p=0.12). Discussion:. Multimodal IOM is highly sensitive and specific for spinal cord injury. This technique is reliable to assess the condition of the spinal cord during high-risk major spinal deformity surgery. Conflict of interest statement: None

Aim of Study. To highlight the absence of an important pitfall in the Advanced Trauma Life Support protocol in application of rigid collar to patients with potentially unstable cervical spine injury. Study Method. We present a case series of two patients with ankylosed cervical spines who developed neurological complications following application of rigid collar for cervical spine injuries as per the ATLS protocol. This has been followed up with a survey of A&E and T&O doctors who regularly apply cervical collars for suspected unstable cervical spine injuries. The survey was conducted telephonically using a standard questionnaire. 75 doctors completed the questionnaire. A&E doctors = 42, T&O = 33. Junior grade = 38, middle grade = 37. Trauma management frontline experience >1yr = 50, <1yr = 25. Of the 75 respondents 68/75 (90.6%) would follow the ATLS protocol in applying rigid collar in potentially unstable cervical spine injuries. 58/75 (77.3%) would clinically assess the patient prior to applying collar. Only 43/75 (57.3%) thought the patients relevant past medical history would influence collar application. Respondents were asked whether they were aware of any pitfalls to rigid collar application in suspected neck injuries. 34/75 (45.3%) stated that they were NOT aware of pitfalls. The lack of awareness was even higher 17/25 (68%) amongst doctors with less that 12 months frontline experience. When directly asked whether ankylosing spondylitis should be regarded as a pitfall then only 43/75 (57.3%) answered in the affirmative. Conclusion. We would like to emphasise the disastrous consequences of applying a rigid collar in patients with ankylosed cervical spine. The survey demonstrates the lack of awareness (∼50%) amongst A&E and T&O doctors regarding pitfalls to collar application. We recommend the ATLS manual highlight a pitfall for application of rigid collars in patients with ankylosed spines and suspected cervical spine injuries