Study design. Literature review of the best available evidence on the accuracy of computer assisted pedicle screw insertion. Background. Pedicle screw misplacement rates with the conventional insertion technique and adequate postoperative CT examination have ranged from 5 to 29 % in the cervical spine, from 3 to 58 % in the thoracic spine, and from 6 to 41% in the lumbosacral region. Despite these relatively high perforation rates, the incidence of reported screw-related complications has remained low. Interestingly, the highest rates of neurovascular injuries have been reported from the lumbosacral spine in up to 17% of the patients. Gertzbein and Robbins introduced a 4-mm “safe zone” in the thoracolumbar spine for medial encroachment, consisting of 2-mm of epidural and 2-mm of subarachnoid space. Later, several authors have found the safety margins to be significantly smaller, suggesting that the “safe zone” thresholds of Gertzbein and Robbins do not apply to the thoracic spine, and seem to be too high even for the lumbar spine. The midthoracic and midcervical spine, as well as the thoracolumbar junction set the highest demands for accuracy in pedicle screw insertion, with no room for either translational or rotational error at e.g. T5 level. Computer assisted pedicle screw insertion (navigation) was introduced in the early 90's to increase the accuracy and safety of pedicle screw insertion. Material. PubMed literature search revealed two randomized controlled trials (RCT) comparing the in vivo accuracy of conventional and computer assisted pedicle screw insertion techniques. Three meta-analyses have assessed the published reports on the accuracy of pedicle screw insertion with or without computer assistance, one additional meta-analysis concentrated on the functional outcome of computer assisted pedicle screw insertion. Results. The RCTs by Laine et al and Rajasekaran et al achieved significantly higher screw placement accuracy with computer assistance than with the conventional techniquebased on anatomical landmarks. In a degenerative patient population, Laine et al reported a misplacement rate of 4.6% with computer assistance compared to 13.4% with the conventional technique. In addition to this quantitative difference, a qualitative difference in the misplaced screws was noticed: in the conventional group, 28 out of 37 misplaced screws were either inferior or medial, whereas in the computer assisted group, 1 out of 10 misplaced screws was situated in these ”danger zones”. In deformity surgery, Rajasekaran et al reported a 2% pedicle screw misplacement rate with a computer assisted technique compared to 23% with the conventional technique. Interestingly, in their study, the average screw insertion time in the computer assisted group was significantly shorter than with the conventional technique. The three meta-analyses, assessing up to 37 337 pedicle screws, reported significantly higher accuracy in the placement of pedicle screws with computerassistance compared with the conventional methods. The superiority of the computer assisted technique was even more obvious with abnormal surgical anatomy. CT-based and 3D-fluoroscopy-based navigation methods provided better accuracy compared to 2Dfluoroscopy-based navigation. No statistically significant benefit with computer assistance in the incidence of neuro-vascular complications, or in functional outcome was demonstrated. Conclusion. High pedicle screw misplacement rates have been reported with the conventional technique based on anatomical landmarks and intraoperative fluoroscopy. The concept of ”safe zone” is hypothetical, and underestimates the true risks of misplaced pedicle screws. Computer assistance significantly improves the accuracy and safety of pedicle screw insertion. It will, however, be difficult to correlate this increased accuracy to improved patient outcomes

We validated the North American Spine Society (NASS) outcome-assessment instrument for the lumbar spine in a computerised touch-screen format and assessed patients’ acceptance, taking into account previous computer experience, age and gender. Fifty consecutive patients with symptomatic and radiologically-proven degenerative disease of the lumbar spine completed both the hard copy (paper) and the computerised versions of the NASS questionnaire. Statistical analysis showed high agreement between the paper and the touch-screen computer format for both subscales (intraclass correlation coefficient 0.94, 95% confidence interval (0.90 to 0.97)) independent of computer experience, age and gender. In total, 55% of patients stated that the computer format was easier to use and 66% preferred it to the paper version (p < 0.0001 among subjects expressing a preference). Our data indicate that the touch-screen format is comparable to the paper form. It may improve follow-up in clinical practice and research by meeting patients’ preferences and minimising administrative work

Purpose of study and background. Psychological factors are considered to play a role in development and maintenance of chronic low back pain (CLBP). Stress or anxiety can change pain sensitivity; however, this has predominantly been studied in healthy individuals with limited work in individuals with musculoskeletal pain. The objective of this study was to quantify the effect of acute exposure to a psychosocial stressor on mechanical pain sensitivity in individuals with and without CLBP. Summary of methods and results. Six individuals with CLBP and 10 individuals without CLBP performed a 10-minute computer task under conditions of low and high psychosocial stress. Psychosocial stress was manipulated using mental maths and memory tasks combined with social evaluative threat. The effect of the stressor was evaluated using blood pressure, heart rate and the state anxiety component of the Spielberger State-Trait Anxiety Index. Mechanical pressure pain threshold (PPT) was recorded on the tibialis anterior muscle using a handheld digital pressure algometer. The stress manipulation increased self-reported anxiety (p<0.001), but not blood pressure or heart rate (p>0.06). Change in PPT from low to high stress was greater in the CLBP group (median ΔPPT = −0.5 kg/cm. 2. ) than in the control group (−0.15 kg/cm. 2. ; p=0.005). Conclusion. Individuals experienced an increase in pain sensitivity after acute exposure to a stressor designed to mimic low-level workplace stressors, and this increase was greater in individuals with CLBP than asymptomatic individuals. These results indicate that this experimental model can be used to study links between pain sensitivity and psychosocial stressors and increase our understanding of their potential role in CLBP. Conflicts of Interest: No conflicts of interest. Sources of funding: No funding obtained

Introduction and Objective. Almost 60% of the population can expect to experience low back pain (LBP) during their life. Several radiological tools are used to investigate LBP. However, adequate evidence is unavailable to support the use of single photon emission computer tomography (SPECT) in patients with LBP. The objective of this study is to assess the role and efficiency of SPECT in evaluation and management of patients with LBP. Method. Ninety-two patients with LBP were examined and assessed. All the patients received a magnetic resonance imaging (MRI) scan and were referred for a SPECT. We interpreted the modic and degenerative changes found on the MRI and compared it with SPECT tracer uptake. SPECT was used to identify the pain generator and then a surgical plan was made. Data was analyzed for pain improvement in those who underwent surgical treatment to establish the accuracy of CT SPECT in identification of primary pain generator. Results. A total of 184 patients were included in the study who underwent diagnostic CT-SPECT between January 2013 and December 2019. One hundred of them were females and Eighty four males; the mean age was 47.6 years. 111 patients underwent surgery in the form of interbody fusion or posterolateral fusion. 16 patients positive tracer uptake was at asymptomatic level or unrelated. In 3 patients SPECT identified screw sites as pain generator and in all 3 patients screws were removed with good pain relief. Overall axial pain as measured with Numeric rating scale was preoperatively 9.13 ± 0.7 and improved to 4.54 ± 2.3 at 6 months postoperative follow up. MRI changes have been analyzed and correlation studied with relation to SPECT findings. Conclusion. Due to its high precision and sensitivity compared to other radiological modalities, SPECT demonstrated the ability to aid in clinical diagnosis. CT SPECT reveals information that becomes vital in deciding further management. In this study, we exemplified that SPECT scan can give indication for pain generator in axial spine pain and aid in surgical intervention

Background and aims. The EU-funded Back-UP project aims to develop a cloud computer platform to guide the treatment of low back and neck pain (LBNP) in first contact care and early rehabilitation. In order to identify evidence-based treatment options that can be recommended and are accessible to people with LBNP across Europe, we conducted a systematic review of recently published guidelines. Methods. Electronic databases, including Medline, Embase, CINAHL, PsycINFO, HMIC, Epistemonikos, PEDro, TRIP, NICE, SIGN, WHO, Guidelines International Network (G-I-N) and DynaMed Plus were searched. We searched for guidelines published by European health professional or guideline development organisations since 2013, focusing on the primary care management of adult patients presenting with back or neck pain (including whiplash associated symptoms, radicular pain, and pregnancy-related LBP). The AGREE-II tool was used to assess the quality of guideline development and reporting. Results. Searches generated 3098 unique citations that were screened for eligibility. A total of 189 full-texts were retrieved, and 18 guidelines were included in the review (from the UK, Germany, France, Italy, Denmark, Poland, Belgium, and the Netherlands). Data extraction showed considerable variation in guideline development processes, especially regarding the methods used for identifying, appraising, and synthesising evidence, and for formulating, agreeing, and grading recommendations. Conclusions. Recommendations for the management of LBNP cover a wide range of treatment options, with self-management advice, analgesics, and exercise proposed as core treatments by most guidelines. A narrative synthesis, taking into account consistency, strength, and quality of guideline recommendations, will be presented. No conflicts of interest. Funding: This abstract presents independent research within the Back-UP project, which has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No. 777090. This document reflects only the views of the authors, and the European Commission is not liable for any use that may be made of its contents. The information in this document is provided “as is”, without warranty of any kind, and accept no liability for loss or damage suffered by any person using this information

Computer assisted surgery is becoming more prevalent in spinal surgery with most published literature suggesting an improvement in accuracy and reduction in radiation exposure. This has been particularly highlighted in scoliosis surgery with regard to the placement of pedicle screws. Anecdotally this has been challenged with concerns with regard to the steep learning curve using this equipment and the high cost of purchasing said systems. The more traditional technique utilises the surgeon's knowledge of anatomic landmarks and tactile palpation added with fluoroscopy to place pedicle screws. We retrospectively looked at 161 scoliosis corrections performed using this technique over three years by 3 main surgeons at the same centre (Frenchay). With an average of 10 levels per procedure and over 2000 pedicle screws inserted. We reviewed the radiation time exposure and dose of radiation given during each case. Our results compared favourably to published data using computer and robot assisted surgery with an average exposure time of 80 seconds and a mean dose of 144 mGy using a standard C-arm guided fluoroscopy. Our study suggests that armed with good surgical knowledge and technique it is possible to obtained low levels of radiation exposure of benefit to both patient and the operating team

Aims

To benchmark the radiation dose to patients during the course of treatment for a spinal deformity.

Aims

Spinal deformity surgery carries the risk of neurological injury. Neurophysiological monitoring allows early identification of intraoperative cord injury which enables early intervention resulting in a better prognosis. Although multimodal monitoring is the ideal, resource constraints make surgeon-directed intraoperative transcranial motor evoked potential (TcMEP) monitoring a useful compromise. Our experience using surgeon-directed TcMEP is presented in terms of viability, safety, and efficacy.

Aims

The timing of surgical fixation in spinal fractures is a contentious topic. Existing literature suggests that early stabilization leads to reduced morbidity, improved neurological outcomes, and shorter hospital stay. However, the quality of evidence is low and equivocal with regard to the safety of early fixation in the severely injured patient. This paper compares complication profiles between spinal fractures treated with early fixation and those treated with late fixation.

To compare outcomes and costs of transforaminal endoscopic surgical discectomy (TES) with those of microdiscectomy (Micro). 48 patients with a primary lumbar disc prolapse were randomly allocated by computer to surgery. Assessments were made of leg and back pain (VAS), Oswestry Disability index (ODI), and SF-36 as primary outcomes. Cost data was collated. 25 TES and 23 Micro patients are reported with similar age, sex, smoking status and affected disc levels (14 v.17 L5/S1). Three months following surgery leg pain scores had decreased by 55 and 65% in the two groups. Patient satisfaction ratings were equal. ODI had decreased 15 points in both groups by 1yr and this improvement was maintained to 2 years (final scores: 7±3 TES v.14±13 Micro - means ±SD; p<0.05). Similar changes were noted in SF36-P. Mean bed stay was lower in the TES group (16 v. 40 hours). Other post-operative costs were similar. There were no immediate complications. One revision was required at 12 months (TES) and one at 18 months (Micro). Two patients presented with a disc prolapse at a different level and side (both TES). Results at up to two years follow-up are similar following the two interventions. Recovery was more rapid in those patients undergoing endoscopic surgery

Purpose. Clinical trials for common health conditions are constantly being designed and implemented in our institution, often with some urgency to meet funding deadlines. The scope and complexity of these trials has resulted in the need for databased computer management systems typically tailored to each project. Even with current advanced software resources, development, testing and implementation can take months for each new project. This presentation describes a new approach to this problem involving an adaptive table-driven software system using project-specific recruitment and screening data which we have developed using visual basic. Methods. The chief design criterion was that the software be reconfigurable by the user based on data tables that contain the parameters of the project design. Essentially, each new project would be implemented by generating new input to the tables, but without the need for reprogramming. The first system implemented was a branching phone screen application that presents questions in an interview format and records participant responses in a data table which can be judged against inclusion/exclusion criteria contained in another table as well as for status reports. Conclusion. The phone screen system is complete and has been implemented in two trials at our institution. Loading the data tables as required to implement the second trial was completed in 1 week. These methods demonstrate the possibility of using careful program design to enable rapid deployment across all phases of the project timeline: in-house clinical screening, treatment and follow-up

To determine the current practice of scoliosis surgery in the UK. A 10 point questionnaire was constructed to identify the philosophy of surgeons on various aspects of scoliosis surgery such as choice of implant, bone graft, autologous blood transfusion (ABT), cord monitoring and computer assisted surgery. Results are compared with the current best evidence. Consultants and Fellows attending the 2009 British Scoliosis Society meeting. 50 questionnaires were completed: 45 Consultants and 5 Fellows. All pedicle screw construct favored by 25/50, hybrid 24/50 (one undecided). Posterior construct of less than 10 levels, 20/50 would not cross-link, 11/50 used one and 19/20 used two or more. More than ten levels 17/50 considered cross-links unnecessary, 4/50 used one and 29/50 used two or more. 88% preferred titanium alloy implants, while a mixture of stainless steel and cobalt chrome was used by others. For bone graft, substitutes (24), iliac crest (14), allograft (12) and demineralised bone matrix (9) in addition to local bone. 10/50 would use recombinant bone morphogenetic protein (3 for revision cases only). 39/50 routinely used intra-operative cell salvage or ABT drains and 4/50 never used autologous blood. All used cord monitoring, Sensory (19/50), Motor (2/50) and combined (29/50). None used computer-aided surgery. 26 operated alone 12 operated in pairs and 12 varied depending on type of case. This survey has brought to light interesting variations in scoliosis surgery in UK. It may reflect the conflicting evidence in the literature

Study design. Prospective clinical and radiological analysis of children with complex cervical deformities for the safety of cervical pedicle screw insertion. Objectives. To analyse the possibility, safety and efficacy of cervical pedicle screw insertion in complex pediatric cervical deformities, where conventional stabilisation techniques would not have provided rigid fixation. Summary of Background Data. Although the usage of cervical pedicle screws (CPS) in adults has become established, the feasibility and safety of its application in children has not been described previously in the literature. Methods. Sixteen children of mean age 9.7 ± 2.6 years (range: 3 - 13) requiring spinal stabilization for cranio-vertebral junction anomalies (n=10), cervico-thoracic kyphosis/ kyphoscoliosis (n=5) and cervical tumor excision (n=1) formed the study group. Feasibility of CPS insertion was assessed by computerised tomography images. Standard 3.0 mm titanium pedicle screws were inserted using intraoperative Iso-C C arm based 3 D computer navigation and the containment was post operatively evaluated with CT scan. Results. Based on preoperative CT imaging, 55 pedicles were selected for screw fixation. Intra operatively CPS was successfully inserted at 51 levels and at four sclerosed pedicles (7.3%), screws could not be inserted. At 42 levels, the screws were inserted in the classical description of pedicle screw application and in nine deformed vertebra, the screws were inserted in a non-classical fashion, taking purchase in the three columns of the cervical vertebra. Forty five (88.3%) screws were fully contained, six (11.7 %) had a non-critical breach and none had a critical breach. No perioperative complications related to pedicle screw insertion were noted. Conclusion. Safe insertion of cervical pedicle screws is possible in children. Iso-C navigation provides real time virtual imaging and improves the safety and accuracy of successful pedicle fixation even in altered vertebral anatomy. Pedicle width morphometrics do not restrict screw insertion

Introduction. Postural and motor activities are the results of interactions of smaller inhibitory and larger facilitating structures of the central nervous system (CNS). In the case of dysbalance of inhibitory and facilitating structures during CNS evolution, the asymmetry of postural activities can appear. This asymmetry remains hidden in the early periods of evolution and becomes apparent in the periods of quick growth and increased hormonal and metabolic activities. Genetic and neural factors have proven to be significant in the cause of idiopathic scoliosis (IS), so we propose a neural developmental hypothesis of this disease. Methods. We evaluated a cohort of 19 patients, all of whom were girls with a mean age of 14·7 years (range 13–18) with right idiopathic thoracic curve (mean Cobb angle 53·5°, range 37–72°; of the apical vertebra from T7 to T9). Heart and pulmonary functions were evaluated by heart ECHO and spiroergometry. Results. Normal heart and pulmonary functions support the opinion that heart and pulmonary changes are not the causative factors in IS. The CNS is specialised computer, so we can found hardware and software damages and faults, resulting in asymmetric function of postural motor muscles. Hardware damage–structural changes from brain cortex to spinal cord–can be of genetic, perinatal, or aquired origin (possibly up to 2 years of age). Software damage–repeated asymmetric positions–can cause an increased plasticity period (quick evolution) of CNS pathological programmes of postural reactions in children at risk of IS–uprighting. Conclusions. Children at risk of IS have postural reaction and postural evolution (quick uprighting) pathology, which can be diagnosed during the first year of age by Vojta diagnostic system. The treatment can be effective only in the period of increased plasticity and development of the CNS, mainly in the first 6 months of age. The symmetric positions and symmetric sensory, and proprioceptive input and motor activities can affect CNS evolution. By slowing down the uprighting the CNS has time to repair the damaged software or replace the damaged connections/programmes. In this way we could minimise structural damage. Developmental hip dysplasia treated by Frejka pillow and Pavlik harness do not affect future motor activities (IS was not detected in these patients). So these controlled motion exercises, which enable symmetric evolution and slow down uprighting of the child, could be a good treatment option in children at risk of IS. Acknowledgments. The study was supported by grant IGA MZd NS/9846-3.846-3

Introduction. Studies of the vestibular system in patients with idiopathic scoliosis (IS) have shown abnormalities in the semicircular canals (SCC) and the basicranium. Rousie (2008) revealed a statistically increased incidence of structural anomalies in the SCCs with three-dimensional computer generated modelling. Some of these findings were replicated in a small population by Cheng (2010). The primary goals of this investigation are verification of SCC abnormalities of patients with IS versus controls with use of three-dimensional modelling with subsequent development of a unique phenotypical classification. Our long-term goal is to provide new direction for hypothesis directed identification and characterisation of genes causally related to IS. Methods. 20 patients with IS and 20 controls matched for age and sex will be identified through the clinic with approval from the institutional review board. Power analyses were done to detect the difference in distributions as the proportion of fisher tests with p values less than 0·05. A sample size of 20 per group gives 86–99% power to realise results under conservative assumptions. IS patients and controls undergo vestibular system examination via T2 MRI imaging. Extracted data are evaluated by a team including Dr Rousie, ENT, radiology, and orthopaedic surgery. DNA is extracted with Gentra Puregene kits from Qiagen (Valencia, CA, USA). Developmental genes related to SCC and axial somatogenesis are being identified through a bioinformatics approach, targeting known IS genomic loci. Custom single-nucleotide polymorphism panels, statistical linkage, and association will identify genes of significance for sequencing. Results. To date, 11 patients with IS and four controls have been recruited. Preliminary data are indicative of a significant percentage of abnormalities within the SCC system in children with IS. Analyses of preliminary findings continue according to the protocol. Conclusions. Research into genetic factors predicting IS progression and/or magnitudes of curvature have been inconclusive. Whether these abnormalities are primary or secondary to a larger systemic issue is speculative; however, they demonstrate a potential new phenotypical classification. Our initial findings show evidence of SCC abnormalities in patients with IS in a well defined patient population compared with healthy controls. Ultimately, our goal for this project is to pursue investigations of genes, pseudogenes, and conserved sequences shown to be related to vestibular structural formation during embryogenesis and development. The identification of a subset of individuals with IS and vestibular abnormalities will allow for the study of genes involved concomitantly in the embryological development of both systems, thus providing insight into the inter-relationship of these deformities

Aims

The aim of this study was to determine the influence of developmental spinal stenosis (DSS) on the risk of re-operation at an adjacent level.

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This study aimed to determine the relationship between pedicle-lengthening distance and bulge-canal volume ratio in cases of lumbar spinal stenosis, to provide a theoretical basis for the extent of lengthening in pedicle-lengthening osteotomies.

Ventral screw osteosynthesis is a common surgical method for treating fractures of the odontoid peg, but there is still no consensus about the number and diameter of the screws to be used. The purpose of this study was to develop a more accurate measurement technique for the morphometry of the odontoid peg (dens axis) and to provide a recommendation for ventral screw osteosynthesis.

Images of the cervical spine of 44 Caucasian patients, taken with a 64-line CT scanner, were evaluated using the measuring software MIMICS. All measurements were performed by two independent observers. Intraclass correlation coefficients were used to measure inter-rater variability.

The mean length of the odontoid peg was 39.76 mm (sd 2.68). The mean screw entry angle α was 59.45° (sd 3.45). The mean angle between the screw and the ventral border of C2 was 13.18° (sd 2.70), the maximum possible mean converging angle of two screws was 20.35° (sd 3.24). The measurements were obtained at the level of 66% of the total odontoid peg length and showed mean values of 8.36 mm (sd 0.84) for the inner diameter in the sagittal plane and 7.35 mm (sd 0.97) in the coronal plane. The mean outer diameter of the odontoid peg was 12.88 mm (sd 0.91) in the sagittal plane and 11.77 mm (sd 1.09) in the coronal plane. The results measured at the level of 90% of the total odontoid peg length were a mean of 6.12 mm (sd 1.14) for the sagittal inner diameter and 5.50 mm (sd 1.05) for the coronal inner diameter. The mean outer diameter of the odontoid peg was 11.10 mm (sd 1.0) in the sagittal plane and 10.00 mm (sd 1.07) in the coronal plane. In order to calculate the necessary screw length using 3.5 mm cannulated screws, 1.5 mm should be added to the measured odontoid peg length when anatomical reduction seems possible.

The cross-section of the odontoid peg is not circular but slightly elliptical, with a 10% greater diameter in the sagittal plane. In the majority of cases (70.5%) the odontoid peg offers enough room for two 3.5 mm cannulated cortical screws.

Cite this article: Bone Joint J 2013;95-B:536–42.

Adolescent idiopathic scoliosis affects about 3% of children. Non-operative measures are aimed at altering the natural history to maintain the size of the curve below 40° at skeletal maturity. The application of braces to treat spinal deformity pre-dates the era of evidence-based medicine, and there is a paucity of irrefutable prospective evidence in the literature to support their use and their effectiveness has been questioned.

This review considers this evidence. The weight of the evidence is in favour of bracing over observation. The most recent literature has moved away from addressing this question, and instead focuses on developments in the design of braces and ways to improve compliance.

Cite this article: Bone Joint J 2013;95-B:1308–16.

We examined the reliability of radiological findings in predicting segmental instability in 112 patients (56 men, 56 women) with a mean age of 66.5 years (27 to 84) who had degenerative disease of the lumbar spine. They underwent intra-operative biomechanical evaluation using a new measurement system. Biomechanical instability was defined as a segment with a neutral zone > 2 mm/N. Risk factor analysis to predict instability was performed on radiographs (range of segmental movement, disc height), MRI (Thompson grade, Modic type), and on the axial CT appearance of the facet (type, opening, vacuum and the presence of osteophytes, subchondral erosion, cysts and sclerosis) using multivariate logistic regression analysis with a forward stepwise procedure. The facet type was classified as sagittally orientated, coronally orientated, anisotropic or wrapped.

Stepwise multivariate regression analysis revealed that facet opening was the strongest predictor for instability (odds ratio 5.022, p = 0.009) followed by spondylolisthesis, MRI grade and subchondral sclerosis. Forward stepwise multivariate logistic regression indicated that spondylolisthesis, MRI grade, facet opening and subchondral sclerosis of the facet were risk factors. Symptoms evaluated by the Short-Form 36 and visual analogue scale showed that patients with an unstable segment were in significantly more pain than those without. Furthermore, the surgical procedures determined using the intra-operative measurement system were effective, suggesting that segmental instability influences the symptoms of lumbar degenerative disease.