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 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. 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

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

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

We determined the frequency, rate and extent of development of scoliosis (coronal plane deformity) in wheelchair-dependent patients with Duchenne muscular dystrophy (DMD) who were not receiving steroid treatment. We also assessed kyphosis and lordosis (sagittal plane deformity). The extent of scoliosis was assessed on sitting anteroposterior (AP) spinal radiographs in 88 consecutive non-ambulatory patients with DMD. Radiographs were studied from the time the patients became wheelchair-dependent until the time of spinal fusion, or the latest assessment if surgery was not undertaken. Progression was estimated using a longitudinal mixed-model regression analysis to handle repeated measurements.

Scoliosis ≥ 10° occurred in 85 of 88 patients (97%), ≥ 20° in 78 of 88 (89%) and ≥ 30° in 66 of 88 patients (75%). The fitted longitudinal model revealed that time in a wheelchair was a highly significant predictor of the magnitude of the curve, independent of the age of the patient (p <  0.001). Scoliosis developed in virtually all DMD patients not receiving steroids once they became wheelchair-dependent, and the degree of deformity deteriorated over time.

In general, scoliosis increased at a constant rate, beginning at the time of wheelchair-dependency (p < 0.001). In some there was no scoliosis for as long as three years after dependency, but scoliosis then developed and increased at a constant rate. Some patients showed a rapid increase in the rate of progression of the curve after a few years – the clinical phenomenon of a rapidly collapsing curve over a few months.

A sagittal plane kyphotic deformity was seen in 37 of 60 patients (62%) with appropriate radiographs, with 23 (38%) showing lumbar lordosis (16 (27%) abnormal and seven (11%) normal).

This study provides a baseline to assess the effects of steroids and other forms of treatment on the natural history of scoliosis in patients with DMD, and an approach to assessing spinal deformity in the coronal and sagittal planes in wheelchair-dependent patients with other neuromuscular disorders.

Cite this article: Bone Joint J 2014;96-B:100–5.

Aims. Severe spinal deformity in growing patients often requires surgical management. We describe the incidence of spinal deformity surgery in a National Health Service. Methods. Descriptive study of prospectively collected data. Clinical data of all patients undergoing surgery for spinal deformity between 2005 and 2018 was collected, compared to the demographics of the national population, and analyzed by underlying aetiology. Results. Our cohort comprised 2,205 patients; this represents an incidence of 14 per 100,000 individuals among the national population aged between zero and 18 years. There was an increase in mean annual incidence of spinal deformity surgery across the study period from 9.6 (7.2 to 11.7) per 100,000 individuals in 2005 to 2008, to 17.9 (16.1 to 21.5) per 100,000 individuals in 2015 to 2018 (p = 0.001). The most common cause of spinal deformity was idiopathic scoliosis accounting for 56.7% of patients. There was an increase in mean incidence of surgery for adolescent idiopathic scoliosis (AIS) (from 4.4 (3.1 to 5.9) to 9.8 (9.1 to 10.8) per 100,000 individuals; p < 0.001), juvenile idiopathic scoliosis (JIS) (from 0.2 (0.1 to 0.4) to one (0.5 to 1.3) per 100,000 individuals; p = 0.009), syndromic scoliosis (from 0.7 (0.3 to 0.9) to 1.7 (1.2 to 2.4) per 100,000 individuals; p = 0.044), Scheuermann’s kyphosis (SK) (from 0.2 (0 to 0.7) to 1.2 (1.1 to 1.3) per 100,000 individuals; p = 0.001), and scoliosis with intraspinal abnormalities (from 0.04 (0 to 0.08) to 0.6 (0.5 to 0.8) per 100,000 individuals; p = 0.008) across the study period. There was an increase in mean number of posterior spinal fusions performed each year from mean 84.5 (51 to 108) in 2005 to 2008 to 182.5 (170 to 210) in 2015 to 2018 (p < 0.001) and a reduction in mean number of growing rod procedures from 45.5 (18 to 66) in 2005 to 2008 to 16.8 (11 to 24) in 2015 to 2018 (p = 0.046). Conclusion. The incidence of patients with spinal deformity undergoing surgery increased from 2005 to 2018. This was largely attributable to an increase in surgical patients with adolescent idiopathic scoliosis. Paediatric spinal deformity was increasingly treated by posterior spinal fusion, coinciding with a decrease in the number of growing rod procedures. These results can be used to plan paediatric spinal deformity services but also evaluate preventative strategies and research, including population screening

Aims. Postoperative complication rates remain relatively high after adult spinal deformity (ASD) surgery. The extent to which modifiable patient-related factors influence complication rates in patients with ASD has not been effectively evaluated. The aim of this retrospective cohort study was to evaluate the association between modifiable patient-related factors and complications after corrective surgery for ASD. Methods. ASD patients with two-year data were included. Complications were categorized as follows: any complication, major, medical, surgical, major mechanical, major radiological, and reoperation. Modifiable risk factors included smoking, obesity, osteoporosis, alcohol use, depression, psychiatric diagnosis, and hypertension. Patients were stratified by the degree of baseline deformity (low degree of deformity (LowDef)/high degree of deformity (HighDef): below or above 20°) and age (Older/Younger: above or below 65 years). Complication rates were compared for modifiable risk factors in each age/deformity group, using multivariable logistic regression analysis to adjust for confounders. Results. A total of 480 ASD patients met the inclusion criteria. By two years, complication rates were 72% ≥ one complication, 28% major, 21% medical, 27% surgical, 11% major radiological, 8% major mechanical, and 22% required reoperation. Younger LowDef patients with osteoporosis were more likely to suffer either a major mechanical (odds ratio (OR) 5.9 (95% confidence interval (CI) 1.1 to 36.9); p = 0.048) or radiological complication (OR 7.0 (95% CI 1.9 to 25.9); p = 0.003). Younger HighDef patients were much more likely to develop complications if obese, especially major mechanical complications (OR 2.8 (95% CI 1.1 to 8.6); p = 0.044). Older HighDef patients developed more complications when diagnosed with depression, including major radiological complications (OR 3.5 (95% CI 1.1 to 10.6); p = 0.033). Overall, a diagnosis of depression proved to be a risk factor for the development of major radiological complications (OR 2.4 (95% CI 1.3 to 4.5); p = 0.005). Conclusion. Certain modifiable patient-related factors, especially osteoporosis, obesity, and mental health status, are associated with an increased risk of complications after surgery for spinal deformity. Surgeons should look for these conditions when assessing a patient for surgery, and optimize them to the fullest extent possible before proceeding to surgical correction so as to minimize the prospect of postoperative morbidity. Cite this article: Bone Joint J 2022;104-B(11):1249–1255

Aims. The aim of this study was to investigate the impact of the level of upper instrumented vertebra (UIV) in frail patients undergoing surgery for adult spine deformity (ASD). Methods. Patients with adult spinal deformity who had undergone T9-to-pelvis fusion were stratified using the ASD-Modified Frailty Index into not frail, frail, and severely frail categories. ASD was defined as at least one of: scoliosis ≥ 20°, sagittal vertical axis (SVA) ≥ 5 cm, or pelvic tilt ≥ 25°. Means comparisons tests were used to assess differences between both groups. Logistic regression analyses were used to analyze associations between frailty categories, UIV, and outcomes. Results. A total of 477 patients were included (mean age 60.3 years (SD 14.9), mean BMI 27.5 kg/m. 2. (SD 5.8), mean Charlson Comorbidity Index (CCI) 1.67 (SD 1.66)). Overall, 74% of patients were female (n = 353), and 49.6% of patients were not frail (237), 35.4% frail (n = 169), and 15% severely frail (n = 71). At baseline, differences in age, BMI, CCI, and deformity were significant (all p = 0.001). Overall, 15.5% of patients (n = 74) had experienced mechanical complications by two years (8.1% not frail (n = 36), 15.1% frail (n = 26), and 16.3% severely frail (n = 12); p = 0.013). Reoperations also differed between groups (20.2% (n = 48) vs 23.3% (n = 39) vs 32.6% (n = 23); p = 0.011). Controlling for osteoporosis, baseline deformity, and degree of correction (by sagittal age-adjusted score (SAAS) matching), frail and severely frail patients were more likely to experience mechanical complications if they had heart failure (odds ratio (OR) 6.6 (95% CI 1.6 to 26.7); p = 0.008), depression (OR 5.1 (95% CI 1.1 to 25.7); p = 0.048), or cancer (OR 1.5 (95% CI 1.1 to 1.4); p = 0.004). Frail and severely frail patients experienced higher rates of mechanical complication than ‘not frail’ patients at two years (19% (n = 45) vs 11.9% (n = 29); p = 0.003). When controlling for baseline deformity and degree of correction in severely frail and frail patients, severely frail patients were less likely to experience clinically relevant proximal junctional kyphosis or failure or mechanical complications by two years, if they had a more proximal UIV. Conclusion. Frail patients are at risk of a poor outcome after surgery for adult spinal deformity due to their comorbidities. Although a definitively prescriptive upper instrumented vertebra remains elusive, these patients appear to be at greater risk for a poor outcome if the upper instrumented vertebra is sited more distally. Cite this article: Bone Joint J 2024;106-B(11):1342–1347

Aims. The aim of this study was to determine whether there is an increased prevalence of scoliosis in patients who have suffered from a haematopoietic malignancy in childhood. Methods. Patients with a history of lymphoma or leukaemia with a current age between 12 and 25 years were identified from the regional paediatric oncology database. The medical records and radiological findings were reviewed, and any spinal deformity identified. The treatment of the malignancy and the spinal deformity, if any, was noted. Results. From a cohort of 346 patients, 19 (5.5%) had radiological evidence of scoliosis, defined as a Cobb angle of > 10°. A total of five patients (1.4% of the total cohort) had a Cobb angle of > 40°, all of whom had corrective surgery. No patient with scoliosis had other pathology as a possible cause of the scoliosis and all had been treated with high doses of steroids for leukaemia, either acute or chronic myeloid, or acute lymphoblastic. Conclusion. There is an increased prevalence of idiopathic-like scoliosis and larger curves (Cobb angle of > 40°) associated with childhood leukaemia, which has not been previously reported in the literature. Causative factors may relate to the underlying disease process and/or its treatment. Cite this article: Bone Joint J 2021;103-B(8):1400–1404

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. Methods. We conducted a randomized, multicentre clinical trial on adolescents undergoing posterior spinal fusion for AIS using segmental pedicle screw instrumentation. A total of 90 consecutive patients were randomized into a ‘drain’ or ‘no drain’ group at the time of wound closure, using the sealed envelope technique (1:1). The primary outcomes in the initial study were the change in the level of haemoglobin in the blood postoperatively and total blood loss. A secondary outcome was the opioid consumption immediately after surgery. The aim of this further study was to report the rate of deep SSI and persistent postoperative pain, at two years' follow-up. Results. As previously reported, the mean 48-hour opioid consumption was significantly higher in the no drain group (2.0 mg/kg (SD 0.8) vs 1.4 mg/kg (SD 0.7); p = 0.005). There were no delayed deep SSIs. At two years’ follow-up, the mean Scoliosis Research Society 24-item questionnaire (SRS-24) total score did not differ between the groups (4.11 (SD 0.47) vs 4.16 (SD 0.33); p = 0.910). The mean SRS-24 pain score was 4.28 (SD 0.48) in the no drain group compared with 4.33 (SD 0.66) in the drain group (p = 0.245). Seven patients (19%) in the no drain group and six in the drain group (14%) reported moderate to severe pain (numerical rating scale ≥ 4) at two years’ follow-up (p = 0.484). The general self-image domain score was significantly higher in the no drain group compared with the drain group (4.02 (SD 0.74) vs 4.59 (SD 0.54); p < 0.001). Conclusion. The main finding in this study was that more severe pain immediately after surgery did not result in a higher incidence of chronic pain in the no drain group compared with the drain group. Back pain and health-related quality of life at two years’ follow-up did not differ between the groups. The patient-reported self-image domain was significantly better in the no drain group compared with the drain group. Cite this article: Bone Joint J 2024;106-B(10):1176–1181

Aims. The aim of this study is to test the hypothesis that three grades of sagittal compensation for standing posture (normal, compensated, and decompensated) correlate with health-related quality of life measurements (HRQOL). Methods. A total of 50 healthy volunteers (normal), 100 patients with single-level lumbar degenerative spondylolisthesis (LDS), and 70 patients with adult to elderly spinal deformity (deformity) were enrolled. Following collection of demographic data and HRQOL measured by the Scoliosis Research Society-22r (SRS-22r), radiological measurement by the biplanar slot-scanning full body stereoradiography (EOS) system was performed simultaneously with force-plate measurements to obtain whole body sagittal alignment parameters. These parameters included the offset between the centre of the acoustic meatus and the gravity line (CAM-GL), saggital vertical axis (SVA), T1 pelvic angle (TPA), McGregor slope, C2-7 lordosis, thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), PI-LL, sacral slope (SS), pelvic tilt (PT), and knee flexion. Whole spine MRI examination was also performed. Cluster analysis of the SRS-22r scores in the pooled data was performed to classify the subjects into three groups according to the HRQOL, and alignment parameters were then compared among the three cluster groups. Results. On the basis of cluster analysis of the SRS-22r subscores, the pooled subjects were divided into three HRQOL groups as follows: almost normal (mean 4.24 (SD 0.32)), mildly disabled (mean 3.32 (SD 0.24)), and severely disabled (mean 2.31 (SD 0.35)). Except for CAM-GL, all the alignment parameters differed significantly among the cluster groups. The threshold values of key alignment parameters for severe disability were TPA > 30°, C2-7 lordosis > 13°, PI-LL > 30°, PT > 28°, and knee flexion > 8°. Lumbar spinal stenosis was found to be associated with the symptom severity. Conclusion. This study provides evidence that the three grades of sagittal compensation in whole body alignment correlate with HRQOL scores. The compensation grades depend on the clinical diagnosis, whole body sagittal alignment, and lumbar spinal stenosis. The threshold values of key alignment parameters may be an indication for treatment. Cite this article: Bone Joint J 2020;102-B(10):1359–1367

Aims. High-grade dysplastic spondylolisthesis is a disabling disorder for which many different operative techniques have been described. The aim of this study is to evaluate Scoliosis Research Society 22-item (SRS-22r) scores, global balance, and regional spino-pelvic alignment from two to 25 years after surgery for high-grade dysplastic spondylolisthesis using an all-posterior partial reduction, transfixation technique. Methods. SRS-22r and full-spine lateral radiographs were collected for the 28 young patients (age 13.4 years (SD 2.6) who underwent surgery for high-grade dysplastic spondylolisthesis in our centre (Scottish National Spinal Deformity Service) between 1995 and 2018. The mean follow-up was nine years (2 to 25), and one patient was lost to follow-up. The standard surgical technique was an all-posterior, partial reduction, and S1 to L5 transfixation screw technique without direct decompression. Parameters for segmental (slip percentage, Dubousset’s lumbosacral angle) and regional alignment (pelvic tilt, sacral slope, L5 incidence, lumbar lordosis, and thoracic kyphosis) and global balance (T1 spino-pelvic inclination) were measured. SRS-22r scores were compared between patients with a balanced and unbalanced pelvis at final follow-up. Results. SRS-22r domain and total scores improved significantly from preoperative to final follow-up, except for the mental health domain that remained the same. Slip percentage improved from 75% (SD 15) to 48% (SD 19) and lumbosacral angle from 70° (SD 11) to 101° (SD 11). Preoperatively, 35% had global imbalance, and at follow-up all were balanced. Preoperatively, 63% had an unbalanced pelvis, and at final follow-up this was 32%. SRS-22r scores were not different in patients with a balanced or unbalanced pelvis. However, postoperative pelvic imbalance as measured by L5 incidence was associated with lower SRS-22r self-image and total scores (p = 0.029). Conclusion. In young patients with HGDS, partial reduction and transfixation improves local lumbosacral alignment, restores pelvic, and global balance and provides satisfactory long-term clinical outcomes. Higher SRS-22r self-image and total scores were observed in the patients that had a balanced pelvis (L5I < 60°) at two to 25 years follow-up. Cite this article: Bone Jt Open 2021;2(3):163–173

Aims. Idiopathic scoliosis is the most common spinal deformity in adolescents and children. The aetiology of the disease remains unknown. Previous studies have shown a lower bone mineral density in individuals with idiopathic scoliosis, which may contribute to the causation. The aim of the present study was to compare bone health in adolescents with idiopathic scoliosis with controls. Methods. We included 78 adolescents with idiopathic scoliosis (57 female patients) at a mean age of 13.7 years (8.5 to 19.6) and 52 age- and sex-matched healthy controls (39 female patients) at a mean age of 13.8 years (9.1 to 17.6). Mean skeletal age, estimated according to the Tanner-Whitehouse 3 system (TW3), was 13.4 years (7.4 to 17.8) for those with idiopathic scoliosis, and 13.1 years (7.4 to 16.5) for the controls. Mean Cobb angle for those with idiopathic scoliosis was 29° (SD 11°). All individuals were scanned with dual energy x-ray absorptiometry (DXA) and peripheral quantitative CT (pQCT) of the left radius and tibia to assess bone density. Statistical analyses were performed with independent-samples t-test, the Mann-Whitney U test, and the chi-squared test. Results. Compared with controls, adolescents with idiopathic scoliosis had mean lower DXA values in the left femoral neck (0.94 g/cm. 2. (SD 0.14) vs 1.00 g/cm. 2. (SD 0.15)), left total hip (0.94 g/cm. 2. (SD 0.14) vs 1.01 g/cm. 2. (SD 0.17)), L1 to L4 (0.99 g/cm. 2. (SD 0.15) vs 1.06 g/cm. 2. (SD 0.17)) and distal radius (0.35 g/cm. 2. (SD 0.07) vs 0.39 g/cm. 2. (SD 0.08; all p ≤ 0.024), but not in the mid-radius (0.72 g/cm. 2. vs 0.74 g/cm. 2. ; p = 0.198, independent t-test) and total body less head (1,559 g (SD 380) vs 1,649 g (SD 492; p = 0.0.247, independent t-test). Compared with controls, adolescents with idiopathic scoliosis had lower trabecular volume bone mineral density (BMD) on pQCT in the distal radius (184.7 mg/cm. 3. (SD 40.0) vs 201.7 mg/cm. 3. (SD 46.8); p = 0.029), but not in other parts of the radius or the tibia (p ≥ 0.062, Mann-Whitney U test). Conclusion. In the present study, idiopathic scoliosis patients seemed to have lower BMD at central skeletal sites and less evident differences at peripheral skeletal sites when compared with controls. Cite this article: Bone Joint J 2020;102-B(2):268–272

Aims. Magnetically controlled growing rods (MCGRs) allow non-invasive correction of the spinal deformity in the treatment of early-onset scoliosis. Conventional growing rod systems (CGRS) need repeated surgical distractions: these are associated with the effect of the ‘law of diminishing returns’. The primary aim of this study was to quantify this effect in MCGRs over sequential distractions. . Patients and Methods. A total of 35 patients with a maximum follow-up of 57 months were included in the study. There were 17 boys and 18 girls with a mean age of 7.4 years (2 to 14). True Distraction (TD) was determined by measuring the expansion gap on fluoroscopy. This was compared with Intended Distraction (ID) and expressed as the ‘T/I’ ratio. The T/I ratio and the Cobb angle were calculated at several time points during follow-up. Results. The mean follow-up was 30 months (6 to 57). There was a significant decrease in the mean T/I ratio over time (convex rod at 3 months 0.81, . sd. 0.58 vs 51 months 0.17, . sd . 0.16, p = 0.0001; concave rod at 3 months 0.93, . sd. 0.67 vs 51 months 0.18, . sd. 0.15, p = 0.0001). A linear decline of the mean T/I ratios was noted for both convex rods (r. 2. = 0.90, p = 0.004) and concave rods (r. 2. = 0.81, p = 0.015) over 51 months. At the 24-month follow-up stage, there was a significant negative correlation between the mean T/I ratio of the concave rod with weight (r = -0.59, p = 0.01), age (r = -0.59, p = 0.01), and BMI of the child (r = -0.54, p = 0.01). Conclusions. The ‘law of diminishing returns’ is also seen after serial distraction using MCGR. Compared to previously published data for CGRS, there is a gradual linear decline rather than a rapid initial decline in lengthening. In older, heavier children a reduced distraction ratio in the concave rod of the MCGR device is noted over time. Cite this article: Bone Joint J 2017;99-B:1658–64

Aims. The aim of this study was to report a retrospective, consecutive series of patients with adolescent idiopathic scoliosis (AIS) who were treated with posterior minimally invasive surgery (MIS) with a mean follow-up of two years (. sd. 1.4; 0.9 to 0 3.7). Our objectives were to measure the correction of the deformity and record the peri-operative morbidity. Special attention was paid to the operating time (ORT), estimated blood loss (EBL), length of stay (LOS) and further complications. Patients and Methods. We prospectively collected the data of 70 consecutive patients with AIS treated with MIS using three incisions and a muscle-splitting approach by a single surgeon between June 2013 and February 2016 and these were retrospectively reviewed. There were eight male and 62 female patients with a mean age of 15 years (. sd. 4.5 ) with a mean body mass index of 19.8 kg/m. 2. (. sd. 5.4). The curves were classified according to Lenke; 40 curves were type 1, 15 were type 2, three were type 3, two were type 4, eight were type 5 and two were type 6. Results. The mean primary Cobb angle was corrected from 58.9° (. sd. 12.6°) pre-operatively to 17.7° (. sd.  10.2°) post-operatively with a mean correction of 69% (. sd. 20%, p < 0.001). The mean kyphosis at T5 to T12 increased from 24.2° (. sd. 12.2°) pre-operatively to 30.1° (. sd. 9.6°, p < 0.001) post-operatively. Peri-operative (30 days) complications occurred in three patients(4.2%): one subcutaneous haematoma, one deep venous thrombosis and one pulmonary complication. Five additional complications occurred in five patients (7.1%): one superficial wound infection, one suture granuloma and three delayed deep surgical site infections. The mean ORT was 337.1 mins (. sd. 121.3); the mean EBL was 345.7 ml (. sd. 175.1) and the mean LOS was 4.6 days (. sd. 0.8). Conclusion. The use of MIS for patients with AIS results in a significant correction of spinal deformity in both the frontal and sagittal planes, with a low EBL and a short LOS. The rate of peri-operative complications compares well with that following a routine open technique. The longer term safety and benefit of MIS in these patients needs to be evaluated with further follow-up of a larger cohort of patients. Cite this article: Bone Joint J 2017;99-B:1651–7

Aims. To address the natural history of severe post-tuberculous (TB) kyphosis, with focus upon the long-term neurological outcome, occurrence of restrictive lung disease, and the effect on life expectancy. . Patients and Methods. This is a retrospective clinical review of prospectively collected imaging data based at a single institute. A total of 24 patients of Southern Chinese origin who presented with spinal TB with a mean of 113° of kyphosis (65° to 159°) who fulfilled inclusion criteria were reviewed. Plain radiographs were used to assess the degree of spinal deformity. Myelography, CT and MRI were used when available to assess the integrity of the spinal cord and canal. Patient demographics, age of onset of spinal TB and interventions, types of surgical procedure, intra- and post-operative complications, and neurological status were assessed. . Results. All except one of the 24 patients were treated with anti-TB chemotherapy when they were first diagnosed with spinal TB. They subsequently received surgery either for neurological deterioration, or deformity correction in later life. The mean follow-up was 34 years (11 to 59) since these surgical interventions. Some 16 patients (66.7%) suffered from late neurological deterioration at a mean of 26 years (8 to 49) after the initial drug treatment. The causes of neurological deterioration were healed disease in nine patients (56.2%), re-activation in six patients (37.5%) and adjacent level spinal stenosis in one patient (6.3%). The result of surgery was worse in healed disease. Eight patients without neurological deterioration received surgery to correct the kyphosis. The mean correction ranged from 97° to 72°. Three patients who were clinically quiescent with no neurological deterioration were found to have active TB of the spine. Solid fusion was achieved in all cases and no patient suffered from neurological deterioration after 42 years of follow-up. On final follow-up, six patients were noted to have deceased (age range: 47 years to 75 years). Conclusion. Our study presents one of the longest assessments of spinal TB with severe kyphosis. Severe post-TB kyphosis may lead to significant health problems many years following the initial drug treatment. Early surgical correction of the kyphosis, solid fusion and regular surveillance may avoid late complications. Paraplegia, restrictive lung disease and early onset kyphosis might relate to early death. Clinically quiescent disease does not mean cure. . Cite this article: Bone Joint J 2017;99-B:1381–8

We report the results of vertebral column resection (VCR) for paediatric patients with spinal deformity. A total of 49 VCRs in paediatric patients from four university hospitals between 2005 and 2009 with a minimum two-year follow-up were retrospectively identified. After excluding single hemivertebral resections (n = 25) and VCRs performed for patients with myelomeningocele (n = 6), as well as spondylectomies performed for tumour (n = 4), there were 14 patients who had undergone full VCR at a mean age of 12.3 years (6.5 to 17.9). The aetiology was congenital scoliosis in five, neuromuscular scoliosis in three, congenital kyphosis in two, global kyphosis in two, adolescent idiopathic scoliosis in one and secondary scoliosis in one. A total of seven anteroposterior and seven posterolateral approaches were used. The mean major curve deformity was 86° (67° to 120°) pre-operatively and 37° (17° to 80°) at the two-year follow-up; correction was a mean of 54% (18% to 86%) in the anteroposterior and 60% (41% to 70%) in the posterolateral group at the two-year follow-up (p = 0.53). The mean Scoliosis Research Society-24 total scores were 100 (92 to 108) for the anteroposterior and 102 (95 to 105) for the posterolateral group. There was one paraparesis in the anteroposterior group necessitating urgent re-decompression, with a full recovery. Patients undergoing VCR are highly satisfied after a successful procedure

The management of spinal deformity in children with univentricular cardiac pathology poses significant challenges to the surgical and anaesthetic teams. To date, only posterior instrumented fusion techniques have been used in these children and these are associated with a high rate of complications. We reviewed our experience of both growing rod instrumentation and posterior instrumented fusion in children with a univentricular circulation. Six children underwent spinal corrective surgery, two with cavopulmonary shunts and four following completion of a Fontan procedure. Three underwent growing rod instrumentation, two had a posterior fusion and one had spinal growth arrest. There were no complications following surgery, and the children undergoing growing rod instrumentation were successfully lengthened. We noted a trend for greater blood loss and haemodynamic instability in those whose surgery was undertaken following completion of a Fontan procedure. At a median follow-up of 87.6 months (interquartile range (IQR) 62.9 to 96.5) the median correction of deformity was 24.2% (64.5° (IQR 46° to 80°) vs 50.5° (IQR 36° to 63°)). We believe that early surgical intervention with growing rod instrumentation systems allows staged correction of the spinal deformity and reduces the haemodynamic insult to these physiologically compromised children. Due to the haemodynamic changes that occur with the completed Fontan circulation, the initial scoliosis surgery should ideally be undertaken when in the cavopulmonary shunt stage. Cite this article: Bone Joint J 2014;96-B:94–9

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