Aims. To benchmark the radiation dose to patients during the course of treatment for a spinal deformity. Methods. Our radiation dose database identified 25,745 exposures of 6,017 children (under 18 years of age) and adults treated for a spinal deformity between 1 January 2008 and 31 December 2016. Patients were divided into surgical (974 patients) and non-surgical (5,043 patients) cohorts. We documented the number and doses of ionizing radiation imaging events (radiographs, CT scans, or intraoperative fluoroscopy) for each patient. All the doses for plain radiographs, CT scans, and intraoperative fluoroscopy were combined into a single effective dose by a medical physicist (milliSivert (mSv)). Results. There were more ionizing radiation-based imaging events and higher radiation dose exposures in the surgical group than in the non-surgical group (p < 0.001). The difference in effective dose for children between the surgical and non-surgical groups was statistically significant, the surgical group being significantly higher (p < 0.001). This led to a higher estimated risk of cancer induction for the surgical group (1:222 surgical vs 1:1,418 non-surgical). However, the dose difference for adults was not statistically different between the surgical and non-surgical groups. In all cases the effective dose received by all cohorts was significantly higher than that from exposure to natural background radiation. Conclusion. The treatment of spinal deformity is radiation-heavy. The dose exposure is several times higher when surgical treatment is undertaken. Clinicians should be aware of this and review their practices in order to reduce the radiation dose where possible. Cite this article: Bone Joint J 2021;103-B(4):1–7

Aims. To report the outcome of spinal deformity correction through anterior spinal fusion in wheelchair-bound patients with myelomeningocele. Methods. We reviewed 12 consecutive patients (7M:5F; mean age 12.4 years (9.2 to 16.8)) including demographic details, spinopelvic parameters, surgical correction, and perioperative data. We assessed the impact of surgery on patient outcomes using the Spina Bifida Spine Questionnaire and a qualitative questionnaire. Results. The mean follow-up was 5.4 years (2 to 14.9). Nine patients had kyphoscoliosis, two lordoscoliosis, and one kyphosis. All patients had a thoracolumbar deformity. Mean scoliosis corrected from 89.6° (47° to 151°) to 46.5° (17° to 85°; p < 0.001). Mean kyphosis corrected from 79.5° (40° to 135°) to 49° (36° to 65°; p < 0.001). Mean pelvic obliquity corrected from 19.5° (8° to 46°) to 9.8° (0° to 20°; p < 0.001). Coronal and sagittal balance restored to normal. Complication rate was 58.3% (seven patients) with no neurological deficits, implant failure, or revision surgery. The degree of preoperative spinal deformity, especially kyphosis and lordosis, correlated with increased blood loss and prolonged hospital/intensive care unit stay. The patients reported improvement in function, physical appearance, and pain after surgery. The parents reported decrease in need for everyday care. Conclusion. Anterior spinal fusion achieved satisfactory deformity correction with high perioperative complication rates, but no long-term sequelae among children with high level myelomeningocele. This resulted in physical and functional improvement and high reported satisfaction. Cite this article: Bone Joint J 2021;103-B(6):1133–1141

Introduction. The British Scoliosis Society published a document in 2008 which set out the minimum standards for paediatric spinal deformity services to achieve over a period of time. But how do the UK paediatric spinal deformity centres measure up to these benchmarks?. Methods. We performed a telephonic survey, contacting every UK spinal deformity centre. The questionnaire probed how each unit compared to the recommended standards. Results. Twenty three centres were interviewed, covering 81 surgeons in total (range 1-8 surgeons per centre). Four centres (17%) did not have 24-hour access to a MRI scanner and all but 2 centres had on-site facilities for long-cassette films/scoliograms. Five centres (22%) always had 2 consultant surgeons per case, 9 centres (39%) routinely have only 1 consultant surgeon per case, and the rest had 1 or 2 consultant surgeons depending on seniority. Six centres (26%) did not routinely have shared care of their patients with the paediatric team. All centres used intra-operative SSEP monitoring, a minority used MEP monitoring (34%), and all but 2 centres had either direct or indirect supervision by a consultant neurophysiologist. All centres have cell saver units available with over half using them routinely (14/23). None of the centres used routine chemoprophylaxis. All units used thromboembolic stockings, with five centres (22%) routinely using foot pumps. Nineteen centres (83%) routinely sent their spinal deformity patients to ITU/PICU postoperatively. Our survey also asked each center what supporting facilities were available, whether they ran adolescent clinics, and whether they participate in multi-disciplinary meetings and audit. In addition, we questioned what typed of drains each center used and the length of time that patients were followed-up. Conclusion. This survey shows how the UK spinal deformity units stand up against the BSS standards, provides an insight in to current UK practice and highlights areas for improvement

Introduction and Objective. The treatment of severe deformities often requiring aggressive techniques such as vertebral resection and osteotomies with high comorbidity. To mitigate this risk, several methods have been used to achieve a partial reduction of stiff curves. The objective of this study was to evaluate and quantify the effectiveness of the Perioperative Halo-Gravity Traction (HGT) in the Treatment of Severe Spinal Deformity in Children. Materials and Methods. A historical cohort of consecutive childs with severe spinal deformity who underwent to a perioperative HGT as a part of the treatment protocol. Minimum follow-up of 2 years. Demographic, clinical and radiological data, including time duration of perioperative HGT and Cobb angle in the coronal and sagittal plane. The radiological variables were measured before the placement of the halo, after placement of the halo, at the end of the period of traction, after surgery and in the final follow-up. Results. Seventeen males (57%) and twenty females (43%) were included in the final analysis. The mean age was 6.5 years (SD 4.8). The most frequent etiology for the spinal deformity was syndromic (13 patients). The average preoperative Cobb angle was 88º (range, 12–135). HGT was used in 17 cases prior to a primary surgery and in 20 cases prior to a revision surgery. After the HGT, an average correction of 34% of the deformity was achieved (p <0.05). After the surgery this correction improved. At 2-year follow-up there was a correction loss of 20% (p <0.05). There were 3 complications (8.1%): 2 pin infections and cervical subluxation. Conclusions. The application of HGT in cases of severe rigid deformity is useful allowing a correction of the preoperative deformity of 34%, facilitating surgery. Preoperative HGT seems to be a safe and effective intervention in pediatric patients with high degree deformity

Aims. To determine the major risk factors for unplanned reoperations (UROs) following corrective surgery for adult spinal deformity (ASD) and their interactions, using machine learning-based prediction algorithms and game theory. Methods. Patients who underwent surgery for ASD, with a minimum of two-year follow-up, were retrospectively reviewed. In total, 210 patients were included and randomly allocated into training (70% of the sample size) and test (the remaining 30%) sets to develop the machine learning algorithm. Risk factors were included in the analysis, along with clinical characteristics and parameters acquired through diagnostic radiology. Results. Overall, 152 patients without and 58 with a history of surgical revision following surgery for ASD were observed; the mean age was 68.9 years (SD 8.7) and 66.9 years (SD 6.6), respectively. On implementing a random forest model, the classification of URO events resulted in a balanced accuracy of 86.8%. Among machine learning-extracted risk factors, URO, proximal junction failure (PJF), and postoperative distance from the posterosuperior corner of C7 and the vertical axis from the centroid of C2 (SVA) were significant upon Kaplan-Meier survival analysis. Conclusion. The major risk factors for URO following surgery for ASD, i.e. postoperative SVA and PJF, and their interactions were identified using a machine learning algorithm and game theory. Clinical benefits will depend on patient risk profiles. Cite this article: Bone Joint Res 2023;12(4):245–255

Aims. The aim of this study was to identify the risk factors for adverse events following the surgical correction of cervical spinal deformities in adults. Methods. We identified adult patients who underwent corrective cervical spinal surgery between 1 January 2007 and 31 December 2015 from the MarketScan database. The baseline comorbidities and characteristics of the operation were recorded. Adverse events were defined as the development of a complication, an unanticipated deleterious postoperative event, or further surgery. Patients aged < 18 years and those with a previous history of tumour or trauma were excluded from the study. Results. A total of 13,549 adults in the database underwent primary corrective surgery for a cervical spinal deformity during the study period. A total of 3,785 (27.9%) had a complication within 90 days of the procedure, and 3,893 (28.7%) required further surgery within two years. In multivariate analysis, male sex (odds ratio (OR) 0.90 (95% confidence interval (CI) 0.8 to 0.9); p = 0.019) and a posterior approach (compared with a combined surgical approach, OR 0.66 (95% CI 0.5 to 0.8); p < 0.001) significantly decreased the risk of complications. Osteoporosis (OR 1.41 (95% CI 1.3 to 1.6); p < 0.001), dyspnoea (OR 1.48 (95% CI 1.3 to 1.6); p < 0.001), cerebrovascular accident (OR 1.81 (95% CI 1.6 to 2.0); p < 0.001), a posterior approach (compared with an anterior approach, OR 1.23 (95% CI 1.1 to 1.4); p < 0.001), and the use of bone morphogenic protein (BMP) (OR 1.22 (95% CI 1.1 to 1.4); p = 0.003) significantly increased the risks of 90-day complications. In multivariate regression analysis, preoperative dyspnoea (OR 1.50 (95% CI 1.3 to 1.7); p < 0.001), a posterior approach (compared with an anterior approach, OR 2.80 (95% CI 2.4 to 3.2; p < 0.001), and postoperative dysphagia (OR 2.50 (95% CI 1.8 to 3.4); p < 0.001) were associated with a significantly increased risk of further surgery two years postoperatively. A posterior approach (compared with a combined approach, OR 0.32 (95% CI 0.3 to 0.4); p < 0.001), the use of BMP (OR 0.48 (95% CI 0.4 to 0.5); p < 0.001) were associated with a significantly decreased risk of further surgery at this time. Conclusion. The surgical approach and intraoperative use of BMP strongly influence the risk of further surgery, whereas the comorbidity burden and the characteristics of the operation influence the rates of early complications in adult patients undergoing corrective cervical spinal surgery. These data may aid surgeons in patient selection and surgical planning. Cite this article: Bone Joint J 2021;103-B(4):734–738

Aims. The routine use of dual-mobility (DM) acetabular components in total hip arthroplasty (THA) may not be cost-effective, but an increasing number of patients undergoing THA have a coexisting spinal disorder, which increases the risk of postoperative instability, and these patients may benefit from DM articulations. This study seeks to examine the cost-effectiveness of DM components as an alternative to standard articulations in these patients. Patients and Methods. A decision analysis model was used to evaluate the cost-effectiveness of using DM components in patients who would be at high risk for dislocation within one year of THA. Direct and indirect costs of dislocation, incremental costs of using DM components, quality-adjusted life-year (QALY) values, and the probabilities of dislocation were derived from published data. The incremental cost-effectiveness ratio (ICER) was established with a willingness-to-pay threshold of $100 000/QALY. Sensitivity analysis was used to examine the impact of variation. Results. In the base case, patients with a spinal deformity were modelled to have an 8% probability of dislocation following primary THA based on published clinical ranges. Sensitivity analysis revealed that, at its current average price ($1000), DM is cost-effective if it reduces the probability of dislocation to 0.9%. The threshold cost at which DM ceased being cost-effective was $1180, while the ICER associated with a DM THA was $71 000 per QALY. Conclusion. These results indicate that under specific clinical and economic thresholds, DM components are a cost-effective form of treatment for patients with spinal deformity who are at high risk of dislocation after THA. Cite this article: Bone Joint J 2018;100-B:1297–1302

Background. The advent of EOS imaging has offered clinicians the opportunity to image the whole skeleton in the anatomical standing position with a smaller radiation dose than standard spine roentgenograms. It is known as the fifth modality of imaging. Current NICE guidelines do not recommend EOS scans over x-rays citing: “The evidence indicated insufficient patient benefit in terms of radiation dose reduction and increased throughput to justify its cost”. Methods. We retrospectively reviewed 103 adult and 103 paediatric EOS scans of standing whole spines including shoulders and pelvis for those undergoing investigation for spinal deformity in a tertiary spinal centre in the UK. We matched this against a retrospective control group of 103 adults and 103 children who underwent traditional roentgenograms whole spine imaging at the same centre during the same timeframe. We aimed to compare the average radiation dose of AP and lateral images between the two modalities. We utilised a validated lifetime risk of cancer calculator (. www.xrayrisk.com. ) to estimate the additional mean risk per study. Results. In the Adult EOS Group (AEG) the mean estimated effective dose of AP was 0.08 mSv (0.04–0.15) and Lateral 0.06 mSv (0.03–0.14). Conversely in the Adult Roentgenograms Group (ARG) the mean AP was 0.49 mSv (0.15–1.88) and Lateral was 0.29 mSv (0.07–1.20). In the Paediatric EOS Group (PEG): the mean dose of AP was 0.07 mSv (0.02–0.21) and Lateral 0.04 mSv (0.02–0.11). Conversely Paediatric Roentgenograms Group (PRG) had a mean dose in AP of 0.37 mSv (0.03–5.92) and in lateral of 0.17 mSv (0.03–0.44). The percentage differences were: ARG:AES AP 613%, ARG:AES Lat 483%, PPG:PEG AP 529%, PRG:PEG Lat 425%. Mean difference 513%. The additional lifetime cancer risk for AEG was 1 in 176056 for males and 1 in 138696 for females, compared to ARG 1 in 31596 for males and 1 in 24894 for females. In PEG that was 1 in 58207 for boys and 1 in 33367 for girls, compared to PRG 1 in 11860 for boys and 1 in 6797 in girls. Differences in additional lifetime risk of cancer per scan: ARG:AES Male 557%, Female 557%, PRG:PEG Male 491%, Females 491%. Conclusion. Standard plain film imaging of the whole spine requires approximately five-times higher doses of radiation compared to dual planar EOS scans. This carries a significant impact when considering the need for repeat imaging on additional lifetime malignancy risk in both children and adults. There is approximately 5-fold increase in risk of cancer for all groups with roentgenograms over EOS. We directly challenge the NICE guidance and recommend EOS dual planar imaging in favour of plane roentgenograms for investigation of spinal deformity

Background. Spinal deformity has a known deleterious effect upon the outcomes of total hip arthroplasty and acetabular component positioning. This study sought to evaluate the relationship between severity of spinal deformity parameters and acetabular cup position, rate of dislocation, and rate of revision among patients with total hip arthroplasties and concomitant spinal deformity. Methods. A prospectively collected database of patients with spinal deformity was reviewed and patients with total hip arthroplasty were identified. The full body standing stereoradiographic images (EOS) were reviewed for each patient. From these images, spinal deformity parameters and acetabular cup anteversion and inclination were measured. A chart review was performed on all patients to determine dislocation and revision arthroplasty events. Statistical analysis was performed to determine correlation of deformity with acetabular cup position. Subgroup analysis was performed for patients with spinal fusion, dislocation events, and revision THA. Results. One-hundred and seven spinal deformity patients were identified, with 139 hips for analysis. The rate of THA dislocation in this cohort was 8.0%, with a revision rate of 5.8% for instability. Patients who sustained dislocations had significantly higher spinopelvic tilt, T1-pelvic angle, and mismatch of lumbar lordosis and pelvic incidence. Among all patients, only 68.8% met the radiographic “safe zone” for anteversion in the standing position (Figure 1). A comparison of radiographic cup position on supine x-ray with standing EOS imaging demonstrated an increase in anteversion of 6.2 degrees. Standing decreased rate of safe zone anteversion of the cup by 20%. Conclusions. In this cohort, patients with THA and concomitant spinal deformity have a particularly high rate of dislocation. This dislocation risk may be driven by the degree of spinal deformity and by spinopelvic compensation, which is suggested by our findings. Arthroplasty surgeons should be aware of the elevated dislocation rate and consider a surgical strategy for maintaining hip stability in this population

Study Design. Retrospective review. Objective. To report the technique and results of vertebral column decancellation (VCD) for the management of sharp angular spinal deformity. Summary of Background Data. The goal of management of sharp angular spinal deformity is to realign the spinal deformity and safely decompress the neurological elements. However, some shortcomings related to current osteotomy treatment for these deformities are still evident. Methods. From January 2004 to March 2007, 45 patients (27 males/18 females) with severe sharp angular spinal deformities at our institution underwent VCD. The diagnoses included 29 congenital kyphoscoliosis and 16 Pott's deformity. The operative technique included multilevel VCD, disc removal, osteoclasis of the concave cortex, compression of the convex cortex accompanied by posterior instrumentation with pedicle screws. Preoperative and postoperative radiographic evaluation was performed. Intraoperative, postoperative and general complications were noted. Results. For a kyphosis type deformity, an average of 2.2 vertebrae was decancellated (range, 2to 4 vertebrae). The mean preoperative kyphosis was +98.6° (range, 82° to 138°), and the meankyphosis in the immediate postoperative period was +16.4° (range, 4° to 30°) with an averagepostoperative correction of +82.2° (range, 61° to 124°). For a kyphoscoliosis type deformity, thecorrection rate was 64% in the coronal plane (from 83.4° to 30.0°) postoperatively and 32.5°(61% correction) at 2 years follow-up. In the sagittal plane, the average preoperative curve of88.5° corrected to 28.6° immediately after surgery and to 31.0° at 2 years follow-up. All patientshad solid fusion at latest follow-up. Complications were encountered in 8 patients (17.8%) andincluded transient neurological deficit and complete paralysis (n = 1). Conclusion. Single stage posterior vertebral column decancellation (VCD) is an effective option to manage severe sharp angular spinal deformities

Abstract: It is known that the treatment of intra or extraspinal paediatric tumours with surgery and radiotherapy or radiotherapy alone can lead to the onset of progressive spinal deformity the management of which can be extremely challenging. We review our series of patients who have developed a spinal deformity in these circumstances. Methods: A review of all patients seen between 1996 and 2007 in the spinal department who have developed a significant spinal deformity following treatment for an intra or extra spinal tumour. Results: 14 patients were identified. The age of presentation to the spinal service was between 2 years 6 months and 15 years 3 months. The underlying diagnoses were Wilms Tumour treated with surgery and radiotherapy in 3, 1 extraspinal sarcoma treated with surgical resection, radiotherapy and chemotherapy, 1 extraspinal neuro-blastoma treated with surgery, radiotherapy, chemotherapy and stem cell rescue and 9 intra spinal tumours (PNET, astrocytoma, ganglioneuroblastoma and der-moid) all managed with resection with or without radiotherapy. The spinal deformities that have developed were thoracic kyphoscoliosis, thoracolumbar kyphosis and lumber hyperlordosis. The spinal management of these deformities has been conservative in 12 with regular assessment to allow intervention if indicated. 2 patients have undergone surgery, a vascularised fibular strut graft and anterior instrumentation in 1 and a non vascularised rib graft in 1 for progressive deformity felt to lead to neurological dysfunction or lung hypoplasia. The cases managed operatively were complicated by poor posterior soft tissues following previous surgery and radiotherapy requiring an anterior approach. In all patients who were treated with radiotherapy platyspondyly was always seen in the vertebral bodies anteriorly and this corresponded to the apex of the deformity. Conclusion: In all children who undergo spinal surgery and or radiotherapy for paediatric tumours there must be ongoing surveillance for the development of a spinal deformity. We feel that this is as much a result of anterior growth arrest secondary to radiotherapy as to posterior laminectomy for intra canal tumour excision. The surgical management of this problem is complex and may require innovative solutions

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

The exact prevalence of scoliosis remains unknown however it appears to be stable over time. In contrast the surgical management of spinal deformity has evolved considerably. In the UK this can be observed by examining recorded hospital statistics. Specifically the volume of procedures undertaken and preferred technique to correct deformity can be analysed and trends captured providing a comprehensive picture of changing UK practice. Annual data tables from 2000 to 2013 were downloaded from the health information and social care UK website which contains Hospital Episode Statistics (HES) data online. Numbers of completed consultant episodes for the four character primary procedure codes V41.1 (posterior attachment of correctional instrument to spine), V41.2 (anterior attachment of correctional instrument to spine), V41.4 (Anterior and posterior attachment of correctional instrument to spine), V41.8 and V41.9 (other specified and other non-specified instrumental correction of spinal deformity respectively) as main procedure where recorded. The total number of attachment of correctional instrument procedures listed as main procedure has increased significantly. The increase consists of higher numbers of posterior attachment procedures over this time from 352 in 2011–2012 to 1967 in 2012–2013 with data demonstrating a year on year increase to 2009–2010 before plateauing. Unspecified and other specified instrumental correctional spinal procedures have also contributed to the overall rise increasing from 206 in 2000–2001 to 447 in 2012–2013. Anterior attachment procedures listed as the main procedure are currently declining in number from a peak of 230 in 2005–2006 to 89 in 2012–2013. Combined posterior and anterior attachment procedures have also decreased marginally from 27 in 2009–2010 to 19 in 2012–2013. Unfortunately combined anterior and posterior procedures were not uniquely coded until 2009–2010. There is also some inherent variability in accuracy of coding which may distort HES data. Despite these limitations these results are likely to represent genuine changes in practice for the surgical correction of spinal deformity over the time period examined

Introduction. Accurate and reproducible cup positioning is one the most important technical factors that affects outcomes of total hip arthroplasty (THA). Although Lewinnek's safe zone is the most accepted range for anteversion and abduction angles socket orientation, the effect of fixed lumbosacral spine on pelvic tilt and obliquity is not yet established. Questions:. What is the change in anteversion and abduction angle from standing to sitting in a consecutive cohort of patients undergoing THA?. What is the effect of fixed and flexible spinal deformities on acetabular cup orientation after THA?. Material and Methods. Between July 2011 and October 2011, 68 consecutive unilateral THAs were implanted in 68 patients with a mean age of 71 ± 6 years old. Radiographic evaluation included standing anteroposterior (AP) and lateral pelvic radiographs, and sitting lateral pelvic radiograph, measuring lumbosacral angle (LSA), sacral angle (SA), and sagittal pelvic tilt angle (SPTA). Computer generated 3D pelvis models were used to analyze the correlation between different pelvic tilts and acetabular cup orientation in abduction and anteversion. Results. The mean standing STPA was 3.7º of anterior tilt (range: −9º of anterior tilt to 25º of posterior tilt). The mean SPTA in sitting was −17.7º of posterior tilt (range: −38º of posterior tilt to 7º of anterior tilt). In a fixed spinal deformity (54%) the SPTA was significantly smaller compared to the flexible pelvis group (10º versus 30.9º, p=0.0001). Flexible pelvises (46%) had a posterior tilt from standing to sitting resulting in increased anteversion. Overall, mean change in LSA and SA from standing to sitting was 22.5º and 20.2º, respectively. The mean post-operative functional anteversion and abduction angles were 19.2º and 42.1º, respectively. In the virtual 3D pelvic models, when the abduction angle was between 40 and 45 degrees, anteversion changed of 0.75 degrees for 1 degree of change of pelvic tilt. Discussion. There is a significant change in pelvic tilt from standing to sitting, especially in patients with flexible spines, where the functional anteversion increases with sitting. Patients with a fixed pelvis have significantly less change in sagittal tilt and therefore less change in anteversion from standing to sitting position. Care should be taken to adjust cup positioning in fixed spinal deformity

Objective. Posterior vertebral column resection (PVCR) is indicated in the management of severe rigid spine deformities. It is a complex surgical procedure and is only performed in a few spine centres due to the technical expertise required and associated risk. The purpose of this study is to review the indications, surgical challenges and outcomes of patients undergoing PVCR. Methods. 12 patients with severe spinal deformities who underwent PVCR were retrospectively reviewed after a follow-up of 2 years. Surgery was performed with the aid of motor evoked spinal cord monitoring and cellsaver when available. The average surgical duration was 310 minutes (100–490). The average blood loss was 1491 ml (0–3500). The indication for PVCR was gross deformity and myelopathy which was due to congenital spinal deformities and one case of old tuberculosis. Clinical records and the radiographic parameters were reviewed. Results. Kyphosis of an average of 72 degrees was corrected to 28 degrees. The associated scoliosis was corrected from an average of 49.2 to 21.2 degrees. Ten patients improved neurologically to ASIA D and E. One patient deteriorated markedly, required revision with no initial improvement but reached ASIA E at 6 months after surgery. Four patients had associated syringomyelia. All were re-scanned at 1 year. The three with small syrinx's demonstrated no progression on MRI and the large syrinx resolved completely. In addition to the neurological deterioration, complications included 1 right lower lobe pneumonia. Conclusion. PVCR is an effective option to correct complex rigid kyphoscoliosis. In addition it allows excellent circumferential decompression of the cord and neurological recovery. When the congenital scoliosis is associated with syringomyelia with no other cause evident, it may allow resolution of the syrinx. Key words: Posterior vertebral column resection, severe spinal deformities, myelopathy, syringomyelia. NO DISCLOSURES

Introduction. Type 1 neurofibromatosis is a serious hereditary disease in which mainly skin, nervous, muscular, and bone systems are damaged. In bone systems the most common deformities are thoracic kyphosis and scoliosis. Data for morphological changes in the structural components of spine in neurofibromatosis are scarce. Thus our study aimed to investigate morphological changes in structural components of the spine in NF1 neurofibromatosis. Methods. Growth plates, intervertebral discs, and fragments of vertebral bodies from deformed and adjacent segments of the spine were obtained from 15 patients aged 10–14 years with scoliosis (Cobb angle 90–120°) caused by neurofibromatosis. Preoperative examination included MRI study of the spine and brain to exclude intracanal masses, and radiographic study of the spine. Patients did not present any neurological symptoms. All children underwent anterior release and interbody fusion. Structural spinal components from children aged 12–14 years collected at forensic autopsy were used as controls. Tissues were investigated by conventional histochemical and ultrastructural methods. The levels of aggrecan and NF1 gene expression were studied with the PCR method. Results. The study of growth plate and intervertebral disc specimens removed during surgery for scoliosis in neurofibromatosis showed a clear boundary between their convex and concave sides. Both growth plate and intervertebral disc in convex side retain their architectonic and histochemical characteristics. The concave side of the growth plate is presented by small chondroblasts densely spaced without a definite orientation and surrounded by homogeneous matrix, which is made up of chondroitin sulphates. These embryonic-type chondroblasts are poorly differentiated. Chondroblasts proliferate beyond the growth plate. Proliferating cells invade into vertebral body and are bordered by thin bone lamellae, causing the scalloping of vertebral body as a radiological symptom of the pathology. Changes occurring in the intervertebral disc are of considerable interest. Concave-side disc is characterised by isolated proliferation zones containing poorly differentiated chondroblasts and fibroblasts, and neurinoma-like masses. Bone trabeculae inside a concave-side vertebra are passing the stage of osteogenesis imperfecta. Detected morphological changes in spinal structures are consistent with findings of Stevenson, who registered cartilage and bone deficiencies in animal model (mice with NF1 genemutation). Thus, morphological studies testify to structural disorder in concave side of the growth plate, but unchanged regularities and stages of chondroblast differentiation and adequate osteogenesis in the convex side. NF1 gene regulates the growth, differentiation, and proliferation of chondroblasts at the early stage of embryogenesis. Gene inactivation at a somite stage results in altered development of definitive spinal structures. Continued growth with adequate proliferation, differentiation, osteogenesis, and topochemical characteristics occurs in the convex-side growth plate, and growth disorder in the concave-side part with continued load cause growth asymmetry and development of spinal deformity. Scoliosis associated with neurofibromatosis is notable for deformity progression and pseudoarthrosis development after surgery. Deformity progression (modulation) should be considered in connection with disorder in osteogenic potency of osteoblasts. Conclusions. The causal factor of spinal deformity development in NF1 neurofibromatosis is NF1 gene mutation. Inactivation of NF1 gene results in disorder in chondrogenesis and osteogenesis within structurally altered zones. A continued load causes development of scoliotic spinal deformity

Background: A sharp, localised, thoracolumbar gibbus is pathognomonic of the mucopolysaccharidosis (MPS) group of disorders, the most common of which is Hurlers syndrome (MPS I). Untreated patients with this disease run an inevitable course of neurological and physical degeneration until death within the first decade. Haemopoietic stem cell transplantation (HSCT) has resulted in considerable improvement in survival with amelioration of many of the symptoms and signs which characterise this disease. Data, however, is disappointing in relation to the impact of HSCT on skeletal dysplasia. This study reviews the natural history of spinal deformity in Hurler’s syndrome after HSCT in infancy. Methods: Twenty three patients (12 male and 11 female), transplanted at a mean age of 0.9 years ± 0.47, (range 0.27 – 1.8yrs) were investigated, of whom 19 were at least two years post-HSCT and were included. HLA identical donor sources included unaffected or heterozygote family members, unrelated adults or cord blood. Mean age at review was 9.4 years ± 4.57, (range 2.5 – 18.4yrs). Serial measurements of the thoracolumbar spines incorporated clinical records, radiographs and surface topography. The thoracolumbar gibbus was measured on lateral spinal radiograph using the standard adaptation of the Cobb method. Two segments of the spine were documented: the gibbus itself and the thoracic profile above it. Clinical assessment and surface topography were contrasted with this. Results: At presentation, all showed the characteristic gibbus at the thoracolumbar junction, with a flat and stiff thoracic spine above. Three patients underwent surgery to correct or maintain the gibbus, which was unsuccessful in two; the third is stable, but still young. Two patients have developed scoliosis: one in the juvenile period and one in infancy. Three female patients are now post-menarchal and have shown no progression of their gibbus. One male patient, now aged 19 years, had significant progression of his gibbus at puberty, but is now stable, untreated and cosmetically acceptable. The remainder are still pre-pubertal but their deformities are not currently progressive. Conclusion: The fate of the spinal deformity in untreated MPS-I has been poorly documented, as the condition was invariably fatal from cardiorespiratory failure during the first decade. These interim results suggest that, while the deformity persists and may become more pronounced during growth and adolescence, it does not significantly impact on quality of life. The considerations which usually dictate intervention in other spinal deformities of childhood may not necessarily apply and should be approached with caution. The more recent availability of recombinant human -L- iduronidase adds further interest to the management of these patients and warrants cautious expectation , in the context of experience gained in these groups of patients. In conclusion atients with MPS I have complex multisystem disorders, independent of their orthopaedic status. While monitoring their spinal deformity is indicated, over-intrusive investigation and treatment may be counterproductive

Two cases of lateral meningocele and spinal deformity in von Recklinghausen's disease are reported. Of the ten known cases of lateral meningocele, seven have occurred in patients with neurofibromatosis. The relation of spinal deformity and neurofibromatosis is briefly discussed

Purpose: Posterior spinal fusion (PSF), with or without anterior spinal fusion (ASF), in conjunction with Luque rod instrumentation (LRI) and Galveston technique is a common procedure in neuromuscular spinal deformity. However, few studies have specifically studied the long-term results and complications of Galveston technique. The purpose of this study was to analyze the long-term results of Galveston technique in combination with PSF, with or without ASF, and LRI in the correction of neuromuscular spinal deformity. We were specifically interested in the stability of the distal foundation, lumbosacral fusion, correction of the associated pelvic obliquity, and complications. Method: Analyzing our Pediatric Orthopaedic Spine Database between 1992–2006, we identified 107 consecutive patients with a neuromuscular spinal deformity who underwent a PSF, with or without ASF, and LRI including Galveston technique, who had a minimum of 2 years postoperative follow-up. There were 55 females and 52 males with a mean age at surgery of 13.5 ± 3.5 years. The mean follow-up was 7.8 ± 3.7 years. We analyzed the coronal and sagittal plane alignment and pelvic obliquity preoperatively, postoperatively, and at last follow-up. We recorded any complications directly related to the Galveston technique. Results: The mean preoperative major curve was 76 ± 21 degrees. At last postoperative follow-up, this measured 33 ± 16 degrees. The mean preoperative pelvic obliquity was 17 ± 10 degrees and at last follow-up 7 ± 6 degrees. Seven patients (6.5%) had Galveston technique complications: three rod breakages, three implant distal migrations and one patient with both rod breakage and distal migration. These occurred late and only one patient required revision surgery. Conclusion: The Galveston technique is an excellent procedure for lumbosacral stabilization in patients with neuromuscular spinal deformity. It provides a solid distal foundation for a lumbosacral fusion and for correction of spinal deformity and pelvic obliquity, with minimal complications

Purpose: The risk of injuring the radial nerves during spine instrumentation to correct spinal deformity is well known and accounts for about 50% of the neurological complications associated with this type of surgery. We describe a technique for monitoring the nerve roots during spinal surgery. Radicular monitoring was described by Hormes in 1993. Material and methods: We report a retrospective analysis of 73 procedures for spinal deformity during which the nerve roots were monitored. The series included 27 men and 46 women, mean age 23.9 years (range 4.5–74.9). Forty patients were less than 18 years old. Procedures included posterior arthrodesis (n=65) and anterior arthrodesis (n=8). Indications were: idiopathic scoliosis (n=32), neurological scoliosis (n=21), congenital scoliosis (n=4), spondylolisthesis (n=2) and kyphosis (n=3). The study group included 68 patients (168 roots) with recordings obtained under the required conditions. The routine procedure involved permanent electrophysiological monitoring of muscle activity with a multi-channel electromyograph. We used microwires implanted within the muscle itself for electrodes. Target muscles depended on the position of the planned implants and the topography of the roots likely to be endangered during the surgical procedure or instrumentation. Explored roots were: T12 (n=9), L1 (n=24, L2 (n=40), L3 (n=24), L4 (n=23), L5 (n=11), S1 (n=22). Monitoring prohibited use of curare during anaesthesia. Results: Prior to radicular monitoring, we had had two root injuries (T12 and L3) which resolved spontaneous (n=139). During the study, changes in the radicular signal were observed in seven patients. All signal anomalies triggered a modification of the surgical procedure and no postoperative deficit was observed. Incidents observed concerned congenital scoliosis (n=2), neurological scoliosis (n=2), and idiopathic scoliosis (n=3). Roots involved were L1 (n=1), L2 (n=2), L3 (n=2), L4 (n= 4), i.e. 11/163. Discussion: Continuous intraoperative monitoring of the spinal roots exposed to surgery for spinal deformity enabled us to identify eleven cases of root suffering among 163 recordings. This permanent monitoring system enabled us to immediately modify the surgical procedure and to control and conflict between the instrumentation and the roots or possible stretching during the correction. This technique requires permanent monitoring during the spinal procedure to avoid false negatives. Curare cannot be used. Conclusion: Intraoperative radicular monitoring is an effective way to avoid radicular complications of this type of surgery. The technique is sensitive and allows immediate adaptation of the surgical procedure. It requires close collaboration between the neurophysiologist, the orthopaedic surgeon and the anaesthesiologist