Background to the study. The use of Patient Reported Outcome Measures (PROMs) to measure effectiveness of care, and supporting patient management is being advocated increasingly. When evaluating outcome it is important to identify a PROM with good measurement properties. Purpose of the study. To review the measurement properties of the low back and neck versions of the Bournemouth Questionnaire. Methods. Bibliographic databases (e.g. EMBASE, MEDLINE, CINAHL and PsycInfo) were searched for articles evaluating the measurement properties of the Bournemouth Questionnaire. Articles were excluded that did not evaluate measurement properties of this instrument. The methodological quality of the studies selected was evaluated using the COSMIN checklist with the four point rating scale. Studies were rated as “excellent”, “good”, “fair” or “poor” based on completion of the checklist. Results. The initial search produced 6265 hits. A total of 13 studies were included in the final evaluation. Seven studies used the Bournemouth Questionnaire neck version, and six studies involved the back version. Cross-cultural translation was reported in six studies, reliability data were reported in eight studies, and responsiveness in ten studies. Conclusion. The review's findings suggest that the Bournemouth Questionnaire has suitable measurement properties for benchmarking practice in musculoskeletal settings. Conflicts of interest. None. Sources of funding. This study was sponsored by the National Council for Osteopathic Research (. www.ncor.org.uk. )

Purpose and background. Static plain radiographs at the end of uncontrolled bending are the current standard of care for measuring translatory slip in back pain patients. Quantitative fluoroscopy systems (QF) that employ standardised bending protocols have been found to improve precision and reduce dose, but comparative data are lacking. We compared 4 QF methods with static radiographs in a control population, calculating ranges, population variation and measurement errors over 6 weeks. Methods. Fifty-four healthy controls (F=22, M=23) received passive recumbent and active weight bearing QF screenings during controlled motion, plus still fluoro imaging in neutral, flexion and extension. The translatory slip of all levels from L2-S1 was determined for each condition using bespoke image tracking codes (Matlab) and pooled to provide means and ranges of variation (+/-1.96SD). The pooled measurement error, or minimal detectable change (MDC. 95. ), reflecting the intra subject repeatability over 6 weeks was calculated. Ranges of translation for each level (L2-S1), for each type of motion were also calculated. Results. Static radiographs at the end of uncontrolled flexion gave the greatest variation and the worst repeatability, while QF recumbent passive and active weight bearing motion with flexion recorded during the motion had ¼ less variation and twice the repeatability. For individual levels, L2-3 had significantly higher flexion ranges in controlled motion than uncontrolled motion, whereas the converse was true at L4-5 (P<0.001). Conclusion. Dynamic QF measurement of flexion translatory slip gives ¼ less population variation and half the measurement error of static radiographs when measured in the same participants. No conflicts of interest. No funding obtained

Background & purpose. Measurement inconsistency across clinical trials is tackled by the development of a core outcome measurement set. Four core outcome domains were recommended for clinical trials in patients with non-specific LBP (nsLBP): physical functioning, pain intensity, health-related quality of life (HRQoL), and number of deaths. This study aimed to reach consensus on core instruments to measure the first three domains. Methods & Results. The Steering Committee overseeing this project selected 17 potential core instruments for physical functioning, three for pain intensity, and five for HRQoL. Evidence on their measurement properties in nsLBP was synthesized in three systematic reviews using COSMIN methodology. Researchers, clinicians, and patients (n = 208) were invited in a Delphi survey to seek consensus on which instruments to endorse as core. Consensus was a-priori set at 67% of participants agreeing on endorsing an instrument. Two Delphi rounds were run (response rates = 44% and 41%). Agreement was reached on endorsing the Oswestry Disability Index (ODI 2.1a) for physical functioning, the Numeric Rating Scale (NRS) for pain intensity, but not on other instruments. Several participants demanded to have free of charge core instruments. Taking these results into account, the steering committee formulated the following recommendations: ODI 2.1a or 24-item Roland Morris Disability Questionnaire for physical functioning, NRS for pain intensity, Short-Form 12 or 10-item PROMIS Global Health for HRQoL. Conclusion. A core outcome measurement set is available for clinical trials in patients with nsLBP. High quality clinimetric studies directly comparing recommended and not recommended instruments are required. Conflict of interest: None. Source of funding: EUROSPINE, The Spine Society of Europe

Introduction. Spinopelvic parameters describe the orientation, shape, and morphology of the spine and pelvis. These parameters change during the first 10 years of life in children without spinal deformity; however, spinopelvic parameters have yet to be defined in children with significant early-onset scoliosis (EOS). Sagittal plane alignment could affect the natural history and outcome of interventions for EOS. As a result, spinopelvic parameters are being defined for this population. On the basis of the landmarks used for measurement of these parameters, there may be inherent error in performing these measurements on the immature pelvis. The purpose of this study is to define the variability associatedwith the measurement of spinopelvic parameters in children with EOS. Methods. Standing, lateral radiographs of 11 patients with untreated EOS were evaluated. Sagittal spinopelvic parameters (pelvic incidence [PI], pelvic tilt [PT], sacral slope [SS], and modified pelvic radius angle [PR]) were measured. To assess intraobserver reliability, these measurements were repeated 15 days apart. To define interobserver reliability, radiographs were measured by 2 independent observers. Results. Average age was 5·7 years and average Cobb angle was 80·8°. Repeated measurements by one observer showed no significant differences for any of the parameters. Paired samples correlations showed a moderate correlation between measurements of PI (0·564), whereas stronger correlations were demonstrated for measurements of PT (0·816), SS (0·947), and PR (0·789). Interobserver analysis showed a significant difference in measurement of SS (p=0·003), whereasmeasurements of PI, PT, and PR did not differ significantly between independent observers. Conclusions. Intraobserver variabilty yielded acceptable correlations for PT, SS, and PR; however, we noted only a moderate correlation for PI. Interobserver analysis showed a significant difference only in SS. The intraobserver and interobserver variablity of measurements for PT and PR were superior than were those for PI and SS. This finding may be related to difficulties in determining the orientation of the sacral endplate in the immature pelvis when measuring PI and SS

Aims. Diagnosis of cauda equina syndrome (CES) remains difficult; clinical assessment has low accuracy in reliably predicting MRI compression of the cauda equina (CE). This prospective study tests the usefulness of ultrasound bladder scans as an adjunct for diagnosing CES. Methods. A total of 260 patients with suspected CES were referred to a tertiary spinal unit over a 16-month period. All were assessed by Board-eligible spinal surgeons and had transabdominal ultrasound bladder scans for pre- and post-voiding residual (PVR) volume measurements before lumbosacral MRI. Results. The study confirms the low predictive value of ‘red flag’ symptoms and signs. Of note ‘bilateral sciatica’ had a sensitivity of 32.4%, and a positive predictive value (PPV) of only 17.2%, and negative predictive value (NPV) 88.3%. Use of a PVR volume of ≥ 200 ml was a demonstrably more accurate test for predicting cauda equina compression on subsequent MRI (p < 0.001). The PVR sensitivity was 94.1%, specificity 66.8%, PPV 29.9% and NPV 98.7%. The PVR allowed risk-stratification with 13% patients deemed ‘low-risk’ of CES. They had non-urgent MRI scans. None of the latter scans showed any cauda equina compression (p < 0.006) or individuals developed subsequent CES in the intervening period. There were considerable cost-savings associated with the above strategy. Conclusion. This is the largest reported prospective evaluation of suspected CES. Use of the PVR volume ≥ 200 ml was considerably more accurate in predicting CES. It is a useful adjunct to conventional clinical assessment and allows risk-stratification in managing suspected CES. If adopted widely it is less likely incomplete CES would be missed. Cite this article: Bone Joint J 2020;102-B(6):677–682

Purpose of the study. Monitoring of scoliosis is traditionally done with radiographs which can be associated with an increased risk of cancer secondary to multiple exposures over many years. This study investigates whether lateral asymmetry (LA) from ISIS2 surface topography can predict radiographic cobb angle, to provide an alternative non- invasive means of monitoring scoliosis patients. Methods. A total of 72 untreated patients with scoliosis (77 curves) with a Cobb angle of 55 degrees or less were included in the study. They had clinical assessment, cobb angle measurement taken from a standard radiograph and surface topography done on the same day. The cobb angle were measured by single surgeon using digital PACS system. The surgeon was unaware of the LA score. Lateral asymmetry was measured using ISIS2 surface topography done by a research nurse who was also unaware of the cobb angle as previously described. Lateral asymmetry was calculated using the standard ISIS2 software. A comparison of cobb angle and LA was performed. Linear regression analysis was performed to define an equation predicting Cobb from LA. The predicted Cobb angles were then compared with the measured radiographic Cobb angles using Bland-Altman analysis. All statistical analysis was carried out using R. Results. The regression equation is: Predicted Cobb = 1.04∗LA + 9.972 with a Pearson correlation coefficient of 0.85 for Cobb angles less than 55 degrees. Bland-Altman analysis of the difference between radiographic Cobb and predicted Cobb from LA gave a mean difference of 0.08 degrees, standard deviation of 6.71 degrees and 95% limits of agreement of −13.3 to 13.5 degrees. For cobb angle less than 55 degrees on radiograph, ISIS2 was able to predict the cobb angle within 13 degrees. Conclusion. Cobb angles themselves display poor reliability, estimates ranging from 3 degrees to 10 degrees. Even so, the 95% confidence limits on the prediction of Cobb angle from ISIS2 LA are too wide to use it alone for monitoring spinal curvature. Whether or not LA is capable of monitoring change in curvature will be investigated as more longitudinal data is built up. Ethics approval: None. Interest Statement: None

Plain radiography has traditionally been used to investigate and monitor patients with adolescent idiopathic scoliosis. The X-ray allows a calculation of the Cobb angle which measures the degree of lateral curvature in the coronal plane. ISIS2 is a surface topography system which has evolved from ISIS, but with much higher precision and speed. It measures the three dimensional shape of the back using structured light and digital photography. This system has the benefit of not requiring any radiation. Lateral asymmetry is the ISIS clinical parameter estimating the curve of the spine in the coronal plane. The aim of this study was to compare this parameter to the Cobb angle measured on plain X-ray. Twelve patients with idiopathic adolescent scoliosis underwent both a standing AP spine X-ray and an ISIS2 scan on multiple occasions. Both scan and X-ray were done within one month of each other. No patient underwent surgery during the study period. The Cobb angle and the degree of lateral asymmetry were calculated. Twelve patients mean age 12.5 years (range 10-16) were investigated using both ISIS2 and X-ray. They had a mean 2.3 (1-5) combined investigations allowing for 30 comparisons. The correlation between the two measurements was r =0.63 (p=0.0002). The Cobb angle measured on ISIS2 was less than that measured by radiograph in 27 out of 30 comparisons. The mean difference between the measurements was mean 6.4° with a standard deviation of 8.2° and 95% confidence interval of 3.3° to 9.4°. In adolescent idiopathic scoliosis, curve severity and rib hump severity are related but measure different aspects of spinal deformity. As expected, these relate closely but not precisely. ISIS2 offers the promise of monitoring scoliosis precisely, without adverse effects from radiation. The small numbers in this series focus on the group of patients with mild to moderate curves at risk of progression. In this group, ISIS2 was able to identify curve stability or progression, without exposing the subjects to radiation

Purpose of the Study

To assess the test-retest reliability, construct validity and determine the cut-off scoret of BACKonLINE™ for people with LBP.

The purpose of this study was to devise a simple but reliable radiological method of identifying a lumbosacral transitional vertebra (LSTV) with a solid bony bridge on sagittal MRI, which could then be applied to a lateral radiograph.

The vertical mid-vertebral angle (VMVA) and the vertical anterior vertebral angle (VAVA) of the three most caudal segments of the lumbar spine were measured on MRI and/or on a lateral radiograph in 92 patients with a LSTV and 94 controls, and the differences per segment (Diff-VMVA and Diff-VAVA) were calculated. The Diff-VMVA of the two most caudal vertebrae was significantly higher in the control group (25° (sd 8) than in patients with a LSTV (type 2a+b: 16° (sd 9), type 3a+b: -9° (sd 10), type 4: -5° (sd 7); p < 0.001). A Diff-VMVA of ≤ +10° identified a LSTV with a solid bony bridge (type 3+4) with a sensitivity of 100% and a specificity of 89% on MRI and a sensitivity of 94% and a specificity of 74% on a lateral radiograph. A sensitivity of 100% could be achieved with a cut-off value of 28° for the Diff-VAVA, but with a lower specificity (76%) on MRI than with Diff-VMVA.

Using this simple method (Diff-VMVA ≤ +10°), solid bony bridging of the posterior elements of a LSTV, and therefore the first adjacent mobile segment, can be easily identified without the need for additional imaging.

Cite this article: Bone Joint J 2013;95-B:1533–7.

To determine the factors that influences the clinical outcomes in surgical correction of thoracic AIS.

There are conflicting data regarding the effects of back shape and radiologic parameters on the self-reported outcomes of surgery in AIS.

Prospective, cohort study; mean follow-up 29 months (range 9-88)

30 patients (5 males);

Rib hump 17 ° corrected to 7 °.

Thoracic Cobb 66 ° corrected to 25 ° (63%). Lumbar Cobb 42 ° corrected to 17°. Thoracic apical vertebral translation (AVT) 48mm corrected to 18mm. Lumbar AVT 34mm corrected to 19mm. Thoracic kyphosis 29° preoperatively 23° postoperatively. Lumbo-sacral lordosis 57° preoperatively 49° postoperatively

Modified SRS Outcomes Instrument (MSRSI) filled out pre-operatively and at final follow up.

Primary= rib hump, radiological (frontal Cobb correction, lumbar & thoracic AVT, sagittal profile), Modified SRS Outcomes Instrument (MSRSI) domain scores.

The magnitude of the rib hump had a significant association with pain:

Rib hump vs. MSRSI pain r= -0.55 p<0.000

Similar correlations existed between rib hump and self-image (r=-0.64, p<0.0000), thoracic Cobb angle with pain (r=-0.48 p<0.0001) and self-image (r= -0.57, P<0.0000). The postoperative thoracic Cobb angle, and percentage thoracic Cobb correction had significant correlations with self-image (r=-0.55 p=0.003 & r=0.54 p0.004 respectively).

The size of the rib hump has a significant impact on pain & self-image. These domains are also significantly influenced by the residual thoracic Cobb angle and overall scoliosis correction.

Background. In vivo evaluation of IVD strains is crucial to better understand normal and pathological IVD mechanics, and to evaluate the effectiveness of treatments. This study aimed to 1) develop a novel in vivo technique based on 3T MRI and digital volume correlation (DVC) to measure strains within IVDs and 2) to use this technique to resolve 3D strains within IVDs of healthy volunteers during extension. Methods. This study included 40 lumbar IVDs from eight healthy subjects. The optimal MR sequence to minimise DVC uncertainties was identified by scanning one subject with four different sequences: CISS, T1VIBE, T2SPACE, and T2TSE. To assess the repeatability of the strain measurements in spines with different anatomical and morphological variations four subjects were scanned with the optimal sequence, and uncertainties of the strain measurements were quantified. Additionally, to calculate 3D strains during extension, MRIs were acquired from six subjects in both the neutral position and after full extension. Results. Measurement errors were lowest when using the T2TSE sequence (precision=0.33 ± 0.10%, accuracy=0.48 ± 0.11%). The largest average maximum tensile and shear strains were seen at the L2-L3 level in all volunteers (7.2 ± 1.5% and 6.8 ± 1.1%, respectively), while the L5-S1 level experienced the lowest average tensile and shear strains (3.5 ± 1.0% and 3.9 ± 0.7%, respectively). Conclusion. The findings of this study establish clinical MRI-based DVC (MRI-DVC) as a new tool for in vivo strain measurement within human IVDs. MRI-DVC successfully provided internal strain distributions within IVDs and has great potential to be used for a wide range of clinical applications. Conflict of interest: No conflicts of interest. Source of funding: This work was supported by the EPSRC, New Investigator Award, EP/V029452/1

Aims. The aim of the study was to determine if there was a direct correlation between the pain and disability experienced by patients and size of their disc prolapse, measured by the disc’s cross-sectional area on T2 axial MRI scans. Methods. Patients were asked to prospectively complete visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores on the day of their MRI scan. All patients with primary disc herniation were included. Exclusion criteria included recurrent disc herniation, cauda equina syndrome, or any other associated spinal pathology. T2 weighted MRI scans were reviewed on picture archiving and communications software. The T2 axial image showing the disc protrusion with the largest cross sectional area was used for measurements. The area of the disc and canal were measured at this level. The size of the disc was measured as a percentage of the cross-sectional area of the spinal canal on the chosen image. The VAS leg pain and ODI scores were each correlated with the size of the disc using the Pearson correlation coefficient (PCC). Intraobserver reliability for MRI measurement was assessed using the interclass correlation coefficient (ICC). We assessed if the position of the disc prolapse (central, lateral recess, or foraminal) altered the symptoms described by the patient. The VAS and ODI scores from central and lateral recess disc prolapses were compared. Results. A total of 56 patients (mean age 41.1 years (22.8 to 70.3)) were included. A high degree of intraobserver reliability was observed for MRI measurement: single measure ICC was 0.99 (95% confidence interval (CI) from 0.97 to 0.99 (p < 0.001)). The PCC comparing VAS leg scores with canal occupancy for herniated disc was 0.056. The PCC comparing ODI for herniated disc was 0.070. We found 13 disc prolapses centrally and 43 lateral recess prolapses. There were no foraminal prolapses in this group. The position of the prolapse was not found to be related to the mean VAS score or ODI experienced by the patients (VAS, p = 0.251; ODI, p = 0.093). Conclusion. The results of the statistical analysis show that there is no direct correlation between the size or position of the disc prolapse and a patient’s symptoms. The symptoms experienced by patients should be the primary concern in deciding to perform discectomy. Cite this article: Bone Joint J 2022;104-B(6):715–720

Aims. This study addressed two questions: first, does surgical correction of an idiopathic scoliosis increase the volume of the rib cage, and second, is it possible to evaluate the change in lung function after corrective surgery for adolescent idiopathic scoliosis (AIS) using biplanar radiographs of the ribcage with 3D reconstruction?. Methods. A total of 45 patients with a thoracic AIS which needed surgical correction and fusion were included in a prospective study. All patients underwent pulmonary function testing (PFT) and low-dose biplanar radiographs both preoperatively and one year after surgery. The following measurements were recorded: forced vital capacity (FVC), slow vital capacity (SVC), and total lung capacity (TLC). Rib cage volume (RCV), maximum rib hump, main thoracic curve Cobb angle (MCCA), medial-lateral and anteroposterior diameter, and T4-T12 kyphosis were calculated from 3D reconstructions of the biplanar radiographs. Results. All spinal and thoracic measurements improved significantly after surgery (p < 0.001). RCV increased from 4.9 l (SD 1) preoperatively to 5.3 l (SD 0.9) (p < 0.001) while TLC increased from 4.1 l (SD 0.9) preoperatively to 4.3 l (SD 0.8) (p < 0.001). RCV was correlated with all functional indexes before and after correction of the deformity. Improvement in RCV was weakly correlated with correction of the mean thoracic Cobb angle (p = 0.006). The difference in TLC was significantly correlated with changes in RCV (p = 0.041). It was possible to predict postoperative TLC from the postoperative RCV. Conclusion. 3D rib cage assessment from biplanar radiographs could be a minimally invasive method of estimating pulmonary function before and after spinal fusion in patients with an AIS. The 3D RCV reflects virtual chest capacity and hence pulmonary function in this group of patients. Cite this article: Bone Joint J 2022;104-B(1):112–119

Background. Scoliosis is described as a lateral spinal curvature exceeding ten degrees on radiograph with vertebral rotation. Approximately 80% of scoliosis presentations are adolescent idiopathic scoliosis (AIS). Current management for AIS in the UK occurs in Surgeon or Paediatrician-led clinics and can be conservative or surgical. The musculoskeletal assessment and triage of AIS appears well-suited to an advanced physiotherapist practitioner (APP) skill set. The aim of this service evaluation was to scope, develop, implement and evaluate a four-month pilot of an APP-led AIS triage pathway. Method and Results. Spinal Consultant deformity and scoliosis clinics were scoped and observed. Clinic inclusion criteria and a patient assessment form was developed. An APP AIS clinic was set up beside a consultant led clinic. All patients assessed were discussed with a spinal surgeon. Consultant and APP agreement (% of total), waiting times, surgical conversion, and patient satisfaction were reviewed. A clinical competency package was developed for training and development of APPs. A total of 49 patients were seen (20 sessions). Waiting list reduced from 10 weeks to 6 weeks. 45%(n=22) of new patients seen were diagnosed with AIS, 27% (n=6) were directly listed for surgery. Consultant/ APP percentage agreement was high for Cobb angle measurement (82%), management plans (90%), and further diagnostic requests (94%). There were no adverse events and high patient satisfaction levels (n=20), (100% Very satisfied or satisfied) were reported. Conclusion. APP-led AIS clinics can provide similar levels of management and assessment as Spinal Consultants with improved waiting times and high levels of satisfaction. Conflicts of interest: No conflicts of interest. Sources of funding: No funding obtained

We present a large single surgeon case series evaluation of a new growth guidance technique for the treatment of progressive early onset scoliosis (EOS). A traditional Luque trolley construct uses wires to hold growth guidance rods together. We describe a new technique that uses domino end to side connectors in place of the wires with the aim of providing a stronger construct to better limit curve progression, while allowing longitudinal growth. We did a thorough retrospective review of patient records and radiological imaging. Sequential measurements of Cobb angle and length of rods were recorded, as well as any further surgical procedures and associated complications. This enabled us to quantify the ability of a technique to limit curve progression and simultaneously allow growth of the construct. In total, 28 patients with EOS (20 idiopathic, four syndromic, and four neuromuscular) have been treated with this technique, 25 of whom have a minimum follow-up of 2 years and 13 have a minimum follow-up of 5 years. The average correction of the preoperative Cobb angle was 48.9%. At the 2-year follow up, the average loss of this initial correction was 15 degrees, rising to only 20 degrees at a minimum of 5 years (including four patients with a follow-up of 8 years or more). The growth of the constructs was limited. The average growth at 2 years was 3.7 mm, rising to 19 mm at the 5-year follow-up. Patients who underwent surgery with this technique before the age of 8 years seemed to do better. This group had a revision rate of only 18% at an average time of 7 years after the index procedure, and the average growth was 22 mm. However, the group that had index surgery after the age of 8 years had a 64% revision rate at an average of 3.2 years after surgery and an average growth of only 11.6 mm. Overall, in the cases series, there were four hardware failures (14%) and one deep infection (3.5%), and only ten patients (36%) had one extra surgery after the index procedure. Only two of the 13 patients who are at a follow-up of 5 years or more have had revision. This modified Luque trolley technique has a good capacity for initial curve correction and for limiting further curve progression, with limited longitudinal growth before 2 years and improved growth thereafter. This technique might not be so useful after the age of 8 years because of poor growth and a higher early revision rate. We have also demonstrated a low cost technique with a low hardware failure rate that saves many future surgeries for the patient compared with other techniques used in the treatment of EOS

Spinal deformations are posture dependent. Official data from the Netherlands show that youth are encountering increasing problems with the musculoskeletal system (>40% back pain, and sport injury proneness). Prolonged sloth and slumped sitting postures are causative factors. Dutch youth are “champion sitting” in Europe. The effects of sitting on the development of posture and function of locomotion (stiffness) during growth have only been reported clearly in classic textbooks (in German) of practical anatomy and orthopaedics. Research with relevant clinical examinations is being done to understand epidemiological data on the increasing posture-dependent problems. A cohort of adolescents (15–18 years) in secondary school was assessed for sagittal postural deviations while bending. 248 children completed a questionnaire, and tests were done on neuromuscular tightness. The femorotibial angle was used to measure hamstring tightness. Measurement of the dorsiflexion of the foot was used to assess the tightness of calf muscles and Achilles tendons. All adolescents were photographed laterally while performing the finger–floor test (used to test flexibility), assessed as a knockout test: “Can you reach the floor or not?” The spinal profiles while bending were classified as abnormal arcuate or angular kyphosis. Hamstring tightness was present in 62.1% of the cohort in both legs, and in 18.2% unilaterally. Achilles tendon tightness was present bilaterally in 59.3%, and unilaterally in 19.4%. Activities with presence of stiffness (finger–floor distance), in descending order, were football, running, no sports, field hockey, tennis, dance, and gymnastics. 93.5% of the soccer players had tight hamstrings in both legs compared with none of those performing gymnastics. The correlation of the finger–floor test with tight hamstrings was 73.2%. For sagittal bending deformities, the correlation between form and function deficits cannot be made yet. 80 of 248 spines were rated by the examiners as having deformed flexion. Since Andry (1741) and at the zenith of continental orthopaedics and anatomy around 1900, the prolonged flexed positions of a young spine were indicated as being the main cause of deformity by overload and shear loads on immature discs and cartilage, preventing normal development of the discs. Nachemson proved that the intradiscal pressure in sitting adults was extremely high, so it follows that children must also be at risk. Evidence suggests that youth, generally because of their sedentary and “screenful lifestyle”, will encounter serious problems in growth, manifesting as incongruent neuro-osseous growth (Roth), serious neuromuscular tightness (being prone to injury), and spinal deformations, leading to pain

The lordosis distribution index (LDI) describes distribution of lumbar lordosis, measured as the % of lower lumbar lordosis (L4-S1) compared to global lordosis (L1-S1) with normal value 50–50%. Maldistributed LDI is associated with higher revision in short lumbar fusions, 4 vertebrae1. We hypothesise maldistributed LDI is also associated with mechanical failure in longer fusions. Retrospective review of 29 consecutive ASD patients, aged 55+, undergoing long lumbar fusion, 4 levels, with >3-years follow-up. LDI, pelvic incidence (PI) and sagittal vertical axis (SVA) were measured on pre- and post-op whole spine standing X-rays (Fig A and B). Patients were categorized according to their pelvic incidence (PI) and postoperative LDI: Normal (LDI 50 80), Hypolordotic (LDI < 50), or Hyperlordotic (LDI > 80) and assessed for failure rate compared to normal LDI and PI <60. Mean follow-up 4.5 years. 19 patients had mechanical failures including junctional failure and metalware fracture. PI >60o was associated with higher mechanical failure rates (Chi^2 p<0.05). Hypolordotic LDI was associated with 82% mechanical failure (Chi^2 p<0.001), Hyperlordotic 88% mechanical failure (Chi^2 p<0.001) and Normal 8% mechanical failure (Table 1). Maldistributed LDI, whether Hyperlordotic or Hypolordotic, correlated with 10× greater mechanical failure rate compared to Normal LDI in long fusions. LDI is a useful measurement that should be considered, especially in high PI patients

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. The aim of this study was to determine the differences in spinal imaging characteristics between subjects with or without lumbar developmental spinal stenosis (DSS) in a population-based cohort. Methods. This was a radiological analysis of 2,387 participants who underwent L1-S1 MRI. Means and ranges were calculated for age, sex, BMI, and MRI measurements. Anteroposterior (AP) vertebral canal diameters were used to differentiate those with DSS from controls. Other imaging parameters included vertebral body dimensions, spinal canal dimensions, disc degeneration scores, and facet joint orientation. Mann-Whitney U and chi-squared tests were conducted to search for measurement differences between those with DSS and controls. In order to identify possible associations between DSS and MRI parameters, those who were statistically significant in the univariate binary logistic regression were included in a multivariate stepwise logistic regression after adjusting for demographics. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported where appropriate. Results. Axial AP vertebral canal diameter (p < 0.001), interpedicular distance (p < 0.001), AP dural sac diameter (p < 0.001), lamina angle (p < 0.001), and sagittal mid-vertebral body height (p < 0.001) were significantly different between those identified as having DSS and controls. Narrower interpedicular distance (OR 0.745 (95% CI 0.618 to 0.900); p = 0.002) and AP dural sac diameter (OR 0.506 (95% CI 0.400 to 0.641); p < 0.001) were associated with DSS. Lamina angle (OR 1.127 (95% CI 1.045 to 1.214); p = 0.002) and right facet joint angulation (OR 0.022 (95% CI 0.002 to 0.247); p = 0.002) were also associated with DSS. No association was observed between disc parameters and DSS. Conclusion. From this large-scale cohort, the canal size is found to be independent of body stature. Other than spinal canal dimensions, abnormal orientations of lamina angle and facet joint angulation may also be a result of developmental variations, leading to increased likelihood of DSS. Other skeletal parameters are spared. There was no relationship between DSS and soft tissue changes of the spinal column, which suggests that DSS is a unique result of bony maldevelopment. These findings require validation in other ethnicities and populations. Level of Evidence: I (diagnostic study). Cite this article: Bone Joint J 2021;103-B(4):725–733

Background. Dynamic measurement of continuous intervertebral motion in low back pain (LBP) research in-vivo is developing. Lumbar motion parameters with the features of biomarkers are emerging and show promise for advancing understanding of personalised biometrics of LBP. However, measurement of changes over time inevitably involve error, due to subjects' natural variation and/or variation in the measurement process. Thus, intra-subject repeatability of parameters to measure changes over time should be established. Methods. Seven lumbar spine motion parameters, measured using quantitative fluoroscopy (QF), were assessed for intra-subject repeatability: Intervertebral range-of-motion (IV-RoM), laxity, motion sharing inequality (MSI), motion sharing variability (MSV), flexion translation and flexion disc height. Intra-subject reliability (ICC) and minimal detectable change (MDC95) of baseline and 6-week follow-up measurements were obtained for 109 healthy volunteers (54 coronal and 55 sagittal). Results. Reliability was substantial to excellent for repeated measurements of IV-RoM, laxity, flexion translation and disc height during recumbent passive motion (ICC:0.69–0.95) and during active weight-bearing motion (ICC:0.64–0.92). MSI was moderate to excellent across both positions (ICC:0.43–0.91). The reliability of MSV was generally poorer for both positions (0.14–0.65). For all parameters, measurement error exceeded 42%. Conclusion. Recumbent IV-RoM, laxity and disc height demonstrated the best repeatability at 6-weeks suggesting they may be better outcome moderators in clinical studies than other variables. However measurement errors for all parameters were higher than the minimal changes of interest. These results are limited to healthy controls and should be regarded as reference values. Similar studies in CNSLBP patients are required. No conflicts of interest. Sources of Funding: Dr Rebecca Hemming received a Seedcorn Bursary from the Cardiff Institute of Tissue Engineering and Repair (CITER) and Professor Alan Breen received a project grant from the European Chiropractors Union Research Fund (ECURF)