Intervertebral Disc Morphology Research Articles

Optimising conservative management of chronic low back pain: study protocol for a randomised controlled trial

BackgroundLower back pain is a global health issue affecting approximately 80% of people at some stage in their life. The current literature suggests that any exercise is beneficial for reducing back pain. However, as pain is a subjective evaluation and physical deficits are evident in low back pain, using it as the sole outcome measure to evaluate superiority of an exercise protocol for low back pain treatment is insufficient. The overarching goal of the current clinical trial is to implement two common, conservative intervention approaches and examine their impact on deficits in chronic low back pain.Methods/designForty participants, 25–45 years old with chronic (>3 months), non-specific low back pain will be recruited. Participants will be randomised to receive either motor control and manual therapy (n = 20) or general strength and conditioning (n = 20) exercise treatments for 6 months. The motor control/manual therapy group will receive twelve 30-min sessions, ten in the first 3 months (one or two per week) and two in the last 3 months. The general exercise group will attend two 1-hour sessions weekly for 3 months, and one or two a week for the following 3 months. Primary outcome measures are average lumbar spine intervertebral disc T2 relaxation time and changes in thickness of the transversus abdominis muscle on a leg lift using magnetic resonance imaging (MRI). Secondary outcomes include muscle size and fat content, vertebral body fat content, intervertebral disc morphology and water diffusion measured by MRI, body composition using dual energy X-ray absorptiometry, physical function through functional tests, changes in corticospinal excitability and cortical motor representation of the spinal muscles using transcranial magnetic stimulation and self-reported measure of pain symptoms, health and disability. Outcome measures will be conducted at baseline, at the 3-month follow-up and at 6 months at the end of intervention. Pain, depressive symptomology and emotions will be captured fortnightly by questionnaires.DiscussionChronic low back pain is ranked the highest disabling disorder in Australia. The findings of this study will inform clinical practice guidelines to assist with decision-making approaches where outcomes beyond pain are sought for adults with chronic low back pain.Trial registrationAustralian New Zealand Clinical Trials Registry, ACTRN12615001270505. Registered on 20 November 2015.

Examining Cervical Intervertebral Disc Morphology with Magnetic Resonance Imaging

Examining Cervical Intervertebral Disc Morphology with Magnetic Resonance Imaging

Investigation of Cervical Intervertebral Discs before and after Surgery for Adolescent Idiopathic Scoliosis

Objective: The aim of this study was to assess the changes in MRI signal intensities of cervical intervertebral discs following corrective surgery in patients with Adolescent Idiopathic Scoliosis (AIS) who were postoperatively followed up for longer than 10 years. Introduction: Sagittal alignment of the cervical spine secondarily may change after corrective surgery in patients with AIS. No previous studies have evaluated MRI images to investigate postoperative changes in cervical intervertebral discs considering cervical alignment that may be influenced by surgical intervention for AIS. Methods: Eighty-nine patients with AIS who underwent MRI scans preoperatively and 10 years postoperatively following surgery. Control group of volunteers with no neck pain underwent MRI on the cervical spine. Both groups were evaluated the signal intensity and morphology of intervertebral discs (nucleus pulposus) on sagittal T2- weighted MRI images of the C2/3 to C7/T1 discs. Nucleus pulposus signal intensity was assessed using that of the spinal cord as reference and classified as normal (N), dehydration (DH), degeneration (DG), and intermediate (IM). Results: The AIS group included 89 cases and the control group included 35 cases. Comparison of pre- and postoperative signal intensity in the AIS group indicated that signal intensity significantly decreased postoperatively for all intervertebral discs (P<0.01) except for the C7/T1 disc. On the other hand, decreased signal intensity accounted for over half of the discs in the control group, except for the C7/T1 disc; however, no statistically significant differences were observed between the postoperative and the control groups. Conclusion: Postoperative cervical disc intensity had significantly reduced in comparison with preoperative values. However, no statistically significant differences were observed between the control and postoperative group with regard to reduced signal intensity. Pre-to postoperative sagittal cervical alignment changes may have affected the changes in signal intensity.

The effect of disc degeneration on anterior shear translation in the lumbar spine: Still more problems lie ahead

Letter to Dr. Linda Sandell: Low back pain is the single most common cause for disability in individuals aged 45 years or younger and as a result carries tremendous weight in socioeconomic considerations. Undoubtedly, numerous factors are contributed to low back pain; mechanical causes of low back pain include degenerative spinal pathologies such as spondylolisthesis, disc herniation, discogenic pain, and so on. Although the study by Melnyk et al.1 has dramatically improved our knowledge about the effect of disc degeneration on anterior translation of the lumbar spine under shear loading, we do not completely agree with the conclusion indicating that disc degeneration, as classified with the Pfirrmann scale, does not predict lumbar spinal motion in shear. First, recent biomechanical studies have revealed distinct behavior at the different lumbar levels2; and the study of lumbar intervertebral disc morphology using MR images has shown segment-dependent geometric features.3 Moreover, different clinical outcomes following surgical treatment at the different lumbar levels have been reported.4 Various factors could influence segment-dependent function of the lumbar spine, such as the surrounding ligaments and muscles, vertebral geometries, the orientation of facet joints, and so on. Notably, the segment-dependent discrepancy may be an inherent factor on the effect of disc degeneration on anterior translation of the lumbar spine under shear loading, which specifically compared at different segment levels are necessary. Further, lumbar disc degeneration is found most often at the L5-S1 level.5 We believe that the study by Melnyk et al.1 has some important limitations. For example, the study only investigated the L3-4 and L4-5 levels that they did not take the other lumbar levels into account, especially the L5-S1 level. Finally, the in-vitro study applied shear loading conditions could be quite different from in-vivo shear loading conditions, which the surrounding ligaments and muscles are not considered. In addition, the in-vivo studies have reported that different abnormal vertebral motions are closely associated with different lumbar disc degenerations graded by Pfirrmann's criteria.6 The conclusion of Melnyk et al.1 may mislead the surgeons on the operative treatment options of lumbar disc degeneration. In the end, we unanimously applaud Melnyk et al. for their significant work and the diligence with which they handled this controversial topic. Currently, it is still more problems waiting to be solved. Therefore, substantial work to determine the effect of disc degeneration on anterior translation of the lumbar spine under shear loading is essential in the near future. YS made substantial contributions to manuscript drafting and approval. DP made substantial contributions to revising the manuscript critically for important intellectual content and approval. ZD made substantial contributions to manuscript revision and approval. WZ made substantial contributions to Conception and design of the manuscript; manuscript revision and approval for the final version submitted. Yi Shen, Dan Peng, Zhihui Dai, Weiye Zhong Department of Orthopaedic Surgery Second Xiangya Hospital and Central South University 139 Middle Renmin Road, Changsha, Hunan 410011, P.R. China

Chronic ingestion of advanced glycation end products induces degenerative spinal changes and hypertrophy in aging pre-diabetic mice.

Intervertebral disc (IVD) degeneration and pathological spinal changes are major causes of back pain, which is the top cause of global disability. Obese and diabetic individuals are at increased risk for back pain and musculoskeletal complications. Modern diets contain high levels of advanced glycation end products (AGEs), cyto-toxic components which are known contributors to obesity, diabetes and accelerated aging pathologies. There is little information about potential effects of AGE rich diet on spinal pathology, which may be a contributing cause for back pain which is common in obese and diabetic individuals. This study investigated the role of specific AGE precursors (e.g. methylglyoxal-derivatives (MG)) on IVD and vertebral pathologies in aging C57BL6 mice that were fed isocaloric diets with standard (dMG+) or reduced amounts of MG derivatives (dMG-; containing 60-70% less dMG). dMG+ mice exhibited a pre-diabetic phenotype, as they were insulin resistant but not hyperglycemic. Vertebrae of dMG+ mice displayed increased cortical-thickness and cortical-area, greater MG-AGE accumulation and ectopic calcification in vertebral endplates. IVD morphology of dMG+ mice exhibited ectopic calcification, hypertrophic differentiation and glycosaminoglycan loss relative to dMG- mice. Overall, chronic exposure to dietary AGEs promoted age-accelerated IVD degeneration and vertebral alterations involving ectopic calcification which occurred in parallel with insulin resistance, and which were prevented with dMG- diet. This study described a new mouse model for diet-induced spinal degeneration, and results were in support of the hypothesis that chronic AGE ingestion could be a factor contributing to a pre-diabetic state, ectopic calcifications in spinal tissues, and musculoskeletal complications that are more generally known to occur with chronic diabetic conditions.

Clinical Results and Functional Outcomes After Direct Intralaminar Screw Repair of Spondylolysis

Prospective analysis. Our objective was to analyze clinical and functional results of patients with spondylolysis treated via direct intralaminar screw fixation and autograft, a minimally invasive and motion-preserving surgery. Spondylolysis is usually treated nonoperatively; multiple surgical techniques are available when nonoperative measures fail. No studies evaluate the clinical and functional outcomes and their correlation with pars defect size and disc morphology on magnetic resonance imaging. We reviewed patients with spondylolysis treated with intralaminar screw fixation and bone grafting from 2000 through 2010. Of the 31 patients (mean age, 16 yr; range, 10-37 yr), 25 (81%) were competitive athletes. Preoperative computed tomographic scans were used to measure the pars defect size, and preoperative magnetic resonance images were graded using Pfirrmann classification for correlation with postoperative outcomes. Student t test was used for analysis (significance, P < 0.05). At a mean follow-up of 60 months (range, 24-135 mo), pain (visual analogue scale score) significantly (P < 0.01) improved: preoperative mean, 7 points (range, 1-10 points); postoperative mean, 2 points (range, 0-10 points). Of the 25 athletes, 19 (76%) returned to competitive sports with a mean postoperative visual analogue scale score of 1 point (range, 0-4 points) at a mean of 6 months (range, 3-10 mo) after surgery. One patient required L6-S2 posterior spinal fusion after spondylolysis repair for persistent pain starting 18 months after intralaminar screw fixation, 2 patients sustained unilateral intralaminar screw fractures at L5, and 1 patient required irrigation and debridement for a superficial postoperative infection. There was no correlation among preoperative magnetic resonance imaging disc morphology, defect size on computed tomography, patient age, and clinical outcomes. Direct repair of spondylolysis with intralaminar screws offers a low profile, reliable treatment with good functional outcome and a low complication rate in active patients. 4.

3D Visualization of Vertebral Growth Plates and Disc: The Effects of Growth Modulation

After tethered growth or sham surgery, spinal motion segments underwent microtomography to determine physeal and disc 3-dimensional (3D) morphology. Instrumented and contralateral sides of tether and sham surgical groups were compared. ObjectivesTo determine the 3D morphological effects of growth modulation via anterolateral tethering on vertebral physeal and intervertebral disc morphology in a rapidly growing bovine model. Summary of background dataGrowth modulation acts through physeal loading. Providing a promising alternative to arthrodesis for scoliosis correction, tethering vertebral growth maintains further growth (open/functioning physes) and motion (disc integrity). Standard physeal and disc evaluation using histology reduces 3D geometries to single planar samples. MethodsFive-week-old calves received anterolateral flexible spinal tethers (n = 6) or sham surgeries (n = 6) followed by 6 months of growth. Individual motion segments were imaged by microtomograph (36 μm). Physeal space and disc space thickness maps were generated from surface reconstructions. Normalized thickness differences were compared between instrumented and contralateral sides of tether and sham groups (analysis of variance, p < .05). Physeal closure was estimated and regions of bony bridging were marked closed. ResultsTethering caused significant physeal thickness reduction on the instrumented side compared with the contralateral side (7.6% ± 2.0%; p = .0002). This reduction was greater (p = .003) in tethered physes than in the sham, which demonstrated no reduction (0.8% ± 3.7%; p = .6). Small regions of physeal closure were observed in sham and tether groups (medians of 1.4% and 0.1% and maximums of 6.8% and 2.7%, respectively). Tethered discs were 29% thinner than sham, but demonstrated no contralateral to instrumented-side thickness difference (5.2% difference; p = .3). ConclusionsTethering resulted in thinner physes on the tethered side without notable physeal closure. With no side differences in the sham group, tethering apparently applied instrument-sided compressive forces. Tethering also resulted in thinner discs, although they were apparently. Producing consistent histological samples is difficult; misaligned slices may lead to inaccurate conclusions. Evaluating entire physes or discs produces more robust results.

Morphological Changes of Lumbar Vertebral Bodies and Intervertebral Discs Associated With Decrease in Bone Mineral Density of the Spine

Cross-sectional study. To investigate changes in the morphology of the lumbar vertebrae and intervertebral discs associated with osteoporosis of the spine in elderly subjects. Osteoporosis is a common condition that primarily affects the elderly with significant impact on quality of life. How exactly osteopenia and osteoporosis influence vertebral and intervertebral disc morphology remains unknown and needs exploration. A total of 395 community-dwelling ambulatory adults from 67 to 89 years of age were studied. The lumbar bone mineral density (BMD) was measured by dual-energy x-ray absorptiometry. T2-weighted sagittal images of the lumbar spine were obtained using a 1.5-T magnet. For each subject, the anterior height (Ha), middle height (Hm), posterior height (Hp), and anterior-posterior (AP) dimension of the 5 lumbar vertebrae (L1-L5) and 6 intervertebral discs (T12-L1 to L5-S1) were measured. To minimize the age effect, volume of these vertebrae and discs was measured in subgroups of 47 men (mean age = 74 yr, range: 73-75 yr) and 67 women (mean age = 72 yr, range: 71-73 yr). Continuous variables were examined by analysis of covariance after adjustment of height and age. There was no significant age difference between the groups of normal BMD, osteopenia, and osteoporosis. For the vertebral bodies, lower BMD was associated with a decrease of Ha, Hm, and Hp but not AP in both sexes, leading to an increased biconcavity index. For the discs, lower BMD was associated with a decrease of Ha and Hp, as well as AP, and an increase in Hm in both men and women. The disc biconvexity index was increased. Lower BMD is associated with an overall decrease in both vertebral volume and disc volume. Lower BMD is associated with a decreasing trend in both lumbar vertebral and disc volumes in elderly subjects but an increase in the Hm of the intervertebral discs.

Changes in intervertebral disc morphology persist 5 mo after 21-day bed rest

As part of the nutrition-countermeasures (NUC) study in Cologne, Germany in 2010, seven healthy male subjects underwent 21 days of head-down tilt bed rest and returned 153 days later to undergo a second bout of 21-day bed rest. As part of this model, we aimed to examine the recovery of the lumbar intervertebral discs and muscle cross-sectional area (CSA) after bed rest using magnetic resonance imaging and conduct a pilot study on the effects of bed rest in lumbar muscle activation, as measured by signal intensity changes in T(2)-weighted images after a standardized isometric spinal extension loading task. The changes in intervertebral disc volume, anterior and posterior disc height, and intervertebral length seen after bed rest did not return to prebed-rest values 153 days later. While recovery of muscle CSA occurred after bed rest, increases (P ≤ 0.016) in multifidus, psoas, and quadratus lumborum muscle CSA were seen 153 days after bed rest. A trend was seen for greater activation of the erector spinae and multifidus muscles in the standardized loading task after bed rest. Greater reductions of multifidus and psoas CSA muscle and greater increases in multifidus signal intensity with loading were associated with incidence of low back pain in the first 28 days after bed rest (P ≤ 0.044). The current study contributes to our understanding of the recovery of the lumbar spine after 21-day bed rest, and the main finding was that a decrease in spinal extensor muscle CSA recovers within 5 mo after bed rest but that changes in the intervertebral discs persist.

Morphology of the thoracic intervertebral disc in the adult spine

ObjectiveTo determine the morphology of the thoracic intervertebral disc (IVD) in the adult spine.IntroductionThere is a paucity of research available regarding the structure of the thoracic intervertebral disc. Despite this, a knowledge and understanding of morphology provides the clinician with a better understanding of regional function and pathology.MethodologyThe morphology of the intervertebral disc of 8 embalmed spines was studied via micro‐dissection of the posterior aspect of the motion segment. As a control of dissection technique one cervical spine and two lumbar segments were micro‐dissected and compared to published findings. Spines were removed from the donor using a posterior approach and were cleaned of superficial soft tissue and sectioned transversely through even numbered vertebral bodies. The posterior neural arch was removed via paracoronal sectioning and the costovertebral joint accessed. The posterior longitudinal ligament was removed in sequential layer dissection. The superior vertebral body was resected down to the vertebral endplate which was then cleared via curette. Results were journal and photo documented.ResultsThe thoracic IVD demonstrates a morphological structure that is unique to other regions. Horizontal cleft fissuring as demonstrated in the cervical spine was significantly less developed and limited to the costovertebral region with no posterior midline migration. One spine failed to reveal fissuring. There was a high rate of end plate defects and variable nuclear fibrosis.ConclusionsThe thoracic IVD is a morphologically distinct structure from the adjacent cervical and lumbar spines.Grant Funding Source: NA

MRI reporting by radiographers: Findings of an accredited postgraduate programme

Aim To analyse the objective structured examination (OSE) results of the first three cohorts of radiographers ( n = 39) who completed an accredited postgraduate certificate (PgC) programme in reporting of general magnetic resonance imaging (MRI) investigations and to compare the agreement rates with those demonstrated for a small group of consultant radiologists. Method Forty MRI investigations were used in the OSE which included the following anatomical areas and abnormal appearances: knee; meniscal/ligament injuries, bone bruises, effusions and osteochondral defects; lumbar spine: intervertebral disc morphology, vertebral collapse, tumours (bone and soft tissue), spinal stenosis and/or nerve root involvement; internal auditory meati (IAM): acoustic neuroma. Incidental findings included maxillary polyp, arachnoid cyst, renal cyst, hydroureter, pleural effusion and metastases (adrenal, lung, perirenal and/or thoracic spine). Sensitivity, specificity and total percentage agreement rates were calculated for all radiographers ( n = 39) using all reports ( n = 1560). A small representative subgroup of reports ( n = 27) was compared to the three consultant radiologists' reports which were produced when constructing the OSE. Kappa values were estimated to measure agreement in four groups: consultant radiologists only; radiographers and each of the consultant radiologists independently. Results The sensitivity, specificity and agreement rates for the three cohorts (combined) of radiographers were 99.0%, 99.0% and 89.2%, respectively. For the majority (5/9) of anatomical areas and/or pathological categories no significant differences ( p < 0.05) were found between the mean Kappa scores ( K = 0.47–0.76) for different groups of observers, whether radiographers were included in the group analysis or not. Where differences were apparent, this was in cases (4/9) where the variation was either not greater than found between radiologists and/or of no clinical significance. These results suggest therefore that in an academic setting, these groups of radiographers have the ability to correctly identify normal investigations and are able to provide a report on the abnormal appearances to a high standard. Further work is required to confirm the clinical application of these findings.

Identification of Cell Proliferation Zones, Progenitor Cells and a Potential Stem Cell Niche in the Intervertebral Disc Region

Descriptive experimental study in 4 different mammals. To investigate cell proliferation/regeneration and localize stem cells/progenitor cells within the intervertebral disc (IVD). Disc degeneration (DD) is believed to play a major role in patients with chronic lumbar pain. Lately, biologic treatment options for DD have gained increasing interest. Normal regeneration processes within the IVD and have previously been sparsely described and therefore it is of great interest to increase the knowledge about these processes. Methods. Detection of cell proliferations zones and label-retaining cells were done by in vivo 5-bromo-2-deoxyuridine (BrdU) labeling in 18 rabbits, killed after 4, 6, 10, 14, 28, or 56 days. Results were visualized with immunohistochemistry and fluorescence/confocal microscopy. Localization of progenitor cell were further investigated by immunohistochemistry using antibodies towards Notch1, Delta4, Jagged1, C-KIT, KI67, and Stro-1 in normal IVD from rabbits (n = 3), rats (n = 2), minipigs (n = 2), and in human degenerated IVD (n = 4). Further, flowcytometry analysis using progenitor markers were performed on additional human IVD cells (n = 3). BrdU positive cells were found in comparable numbers at early and late time points in most regions of the anulus fibrosus (AF) and nucleus pulposus demonstrating slow ongoing cell proliferation. In the AF border to ligament zone (AFo) and the perichondrium region (P) a stem cell niche-like pattern was determined (a high number of BrdU positive cells at early time points vs. only a few label retaining cells at later time points). In normal and DD tissue from the 4 investigated species progenitor cell markers were detected. Conclusion. The IVD is a tissue with ongoing slow cell proliferation both in the AF and the nucleus pulposus. The stem cell niche pattern detected in AFo and P can be suggested to play a role for IVD morphology and function. These findings may be of importance for the development of biologic treatment strategies.

Analysis of the relationship between morphology of intervertebral disc and some correlated factors following discography in patients with chronic low back pain

Objective: To evaluate the diagnostic effectiveness of discography in discogenic low back pain (LBP). Methods: Ninety-six cases of chronic LBP with or without referred thigh pain were enrolled in this study. All these cases received CT scan following discography once conservative treatment for at least 6 months had failed. There were 42 men and 54 women, aged from 24 to 67 years (average 46.4). Discography was performed on 218 discs. The positive discs were classified morphologically according to the Dallas Discogram Description (DDD). Results: (i) The 56 cases (58.3%) which were positive on discography were divided into two subgroups of age less or more than 50 years. Positive rates for the two subgroups were 33.3% and 66.7%, respectively; (ii) one hundred and twenty-two discs, of which 62 (50.8%) were positive on discography, showed morphologic abnormality, whereas all the discography positive discs showed morphologic abnormality. No complication related to discography was found in any case. Conclusion: (i) Compared with the younger patients, older LBP patients have a lower positive rate of discography despite the presence of more serious degenerative disc changes; (ii) outer layer disruption of the annulus fibrous correlates with positive discography; (iii) MRI intensity changes are not specific in diagnosing discogenic pain. Additional discography is needed to identify the painful disc; and (iv) the contrast volume injected into discs can be affected by a variety of factors which restrict its diagnostic value.

Analysis of the relationship between morphology of intervertebral disc and some correlated factors following discography in patients with chronic low back pain

To evaluate the diagnostic effectiveness of discography in discogenic low back pain (LBP). Ninety-six cases of chronic LBP with or without referred thigh pain were enrolled in this study. All these cases received CT scan following discography once conservative treatment for at least 6 months had failed. There were 42 men and 54 women, aged from 24 to 67 years (average 46.4). Discography was performed on 218 discs. The positive discs were classified morphologically according to the Dallas Discogram Description (DDD). (i) The 56 cases (58.3%) which were positive on discography were divided into two subgroups of age less or more than 50 years. Positive rates for the two subgroups were 33.3% and 66.7%, respectively; (ii) one hundred and twenty-two discs, of which 62 (50.8%) were positive on discography, showed morphologic abnormality, whereas all the discography positive discs showed morphologic abnormality. No complication related to discography was found in any case. (i) Compared with the younger patients, older LBP patients have a lower positive rate of discography despite the presence of more serious degenerative disc changes; (ii) outer layer disruption of the annulus fibrous correlates with positive discography; (iii) MRI intensity changes are not specific in diagnosing discogenic pain. Additional discography is needed to identify the painful disc; and (iv) the contrast volume injected into discs can be affected by a variety of factors which restrict its diagnostic value.

MRI methodological development of intervertebral disc degeneration: a rabbit in vivo study at 9.4 T

Intervertebral disc (IVD) degeneration is a complex process characterized by biochemical and structural changes in both the nucleus pulposus and the anulus fibrosus. In this study, we were able to obtain in vivo magnetic resonance (MR) images of the rabbit spine, with several MR imaging (MRI) contrasts (rho, T(1) and T(2)). We quantified several parameters (T(2), apparent diffusion coefficient, disc height and area) to differentiate between healthy and degenerative IVDs and to characterize the degeneration process. To our knowledge, there has not been any previous in vivo study of rabbit IVDs at high-field MRI (9.4 T). A custom radio frequency (RF) coil for 9.4 T was designed to match rabbit IVD morphology, to study the degeneration in vivo on a model of human lumbar disease. Our new probe, a custom half-birdcage-type coil, obtains the necessary exploration depth while meeting the requirements for signal homogeneity and sensitivity of the study. This design addresses some of the difficulties with constructing RF coils at high field strengths.

A method to investigate intervertebral disc morphology from MRI in early idiopathic scoliosis: a preliminary evaluation in a group of 14 patients

The aim of the study was to implement a methodology to quantify in vivo and from magnetic resonance imaging (MRI) the 3D geometrical properties of intervertebral discs (IVDs) in early idiopathic scoliosis with small curves. MRI data were posttreated using a custom-made image processing software to semiautomatically determine the location of disc centres, the location of the nucleus pulposus (NP) and the ratio between the NP volume and the disc volume. MRI was performed in a clinical protocol involving 14 patients having an early idiopathic scoliosis. First, the 3D reconstruction errors were quantified using a reproducibility test (intraoperator and interoperator) in one IVD (L5-S1). The maximal errors in location were 0.79 mm in the frontal plane, 1.84 mm in the sagittal plane and 0.76 mm in the vertical plane. The maximal error in relative volume was 42%. Second, the nucleus migration and relative volume were quantified in discs T5-T6 to L5-S1. No significant relative volume variation was detected. Concerning the disc migration, no significant differences were found in the sagittal and axial planes. In the frontal plane, significant differences were observed at the apex of the scoliotic curvature when the Cobb angle was > or =20 degrees . This innovative study in early scoliosis showed reproducible preliminary results, and its application to improve diagnosis and follow-up will be established in an enlarged patient database.