Sagittal Spinal Curvatures Research Articles

Association of spinal curve deformity and back extensor strength in elderly women with osteoporosis in Japan and the United States

The difference in the shape of sagittal spinal curvature and distribution of vertebral fractures in women of comparable age with osteoporosis from Japan and the United States with different cultures and lifestyles was identified. Back extensor strength was significantly associated with lumbar lordosis in Akita group, indicating the potential importance of strengthening the back extensor. The purpose of the study was to assess the association of osteoporotic spinal deformities with back strength in elderly women in Japan and the United States. Subjects diagnosed with osteoporosis were selected to participate prospectively. In both groups, we measured the angles of thoracic kyphosis and lumbar lordosis with plain lateral radiographs and back extensor strength. The number of vertebral fractures and the ratio of lumbar fractures to thoracic fractures are also evaluated. The level of participants' daily activities was assessed with use of comparable tests in Akita (quality-of-life score) and Minnesota (physical activity score). A total of 102 Japanese women residing in Akita, Japan (Akita group), and 104 white women evaluated in Rochester, MN, USA (Minnesota group), participated in this study. The angle of thoracic kyphosis and lumbar lordosis was higher in the Minnesota group than in the Akita group. The ratio of lumbar fractures to thoracic fractures was higher in the Akita group than in the Minnesota group. In the Akita group, multiple regression analysis revealed that the angle of lumbar lordosis correlated significantly with back extensor strength. We identified the difference in the shape of sagittal spinal curvature and distribution of vertebral fractures in women of comparable age with osteoporosis from two geographic areas of the world with different cultures and lifestyles. Back extensor strength was significantly associated with lumbar lordosis in Akita group, indicating the potential importance of strengthening the back extensor for improving or maintaining lumbar lordosis.

Relationship between Sacral Pelvic Incidence and Acetabular Orientation

The importance of the sacral pelvic incidence (SPI) in relation to individual variations of sagittal spinal curvature has become well-recognised. We attempted to determine the relationship between SPI and acetabular orientation. The three-dimensional coordinates of 47 homologous points were observed on 51 adult anatomical pelvises (26 female and 25 male). The reference vertical plane was Lewinnek's anterior pelvic plane. 10 angular parameters and 11 linear parameters were defined and calculated. These were expressed both in absolute value (in millimetres) and in "acetabular unit" (relative to the mean value of the right and left acetabular rays). Mean values of the parameters were calculated for all pelvises and according to gender. There were two dominant parameters: the "sacral slope" and the "V pubic angle". "Acetabular tilting" was primarily dependent on the "sacral slope" and its intermediary on the "SPI", while "acetabular anteversion" dependent on the "V pubic angle" via the "angle of prow". It is recommended that positioning of the acetabular cup in total hip arthroplasty relates to anatomical parameters, and to the global sagittal balance of the pelvi-spinal unit.

Middle Pleistocene lower back and pelvis from an aged human individual from the Sima de los Huesos site, Spain

We report a nearly complete lumbar spine from the Middle Pleistocene site of the Sima de los Huesos (SH) that is assigned to the previously published SH male Pelvis 1 [Arsuaga JL, et al. (1999). Nature 399: 255-258]. The "SH Pelvis 1 individual" is a unique nearly complete lumbo-pelvic complex from the human Middle Pleistocene fossil record, and offers a rare glimpse into the anatomy and past lifeways of Homo heidelbergensis. A revised reconstruction of Pelvis 1, together with the current fossil evidence, confirms our previous hypothesis that the morphology of this pelvis represents the primitive pattern within the genus Homo. Here we argue that this primitive pattern is also characterized by sexual dimorphism in the pelvic canal shape, implying complicated deliveries. In addition, this individual shows signs of lumbar kyphotic deformity, spondylolisthesis, and Baastrup disease. This suite of lesions would have postural consequences and was most likely painful. As a result, the individual's daily physical activities would have been restricted to some extent. Reexamination of the age-at-death agrees with this individual being over 45 y old, relying on the modern human pattern of changes of the articular surfaces of the os coxae. The presence of degenerative pathological lesions and the advanced age-at-death of this individual make it the most ancient postcranial evidence of an aged individual in the human fossil record. Additional nonpathological SH lumbo-pelvic remains are consistent with previous hypotheses, suggesting a less-pronounced sagittal spinal curvature in Neandertals compared with Homo sapiens.

Influence of hamstring muscle extensibility on spinal curvatures in young athletes

Summary Objectives To determine whether the degree of hamstring muscle extensibility influences the sagittal spinal curvatures in standing, slumped sitting, and maximal trunk flexion on young athletes. Methods Sixty-five elite paddlers (mean age: 13.35 ± 0.61 years) participated in the study. The thoracic and lumbar angles were measured with a Unilevel inclinometer in relaxed standing, slumped sitting, and maximal trunk flexion with knees extended. Pelvic angle was also measured in the maximal trunk flexion. Hamstring muscle extensibility was determined in both legs by passive straight leg raise test (PSLR). The sample was divided into three groups with regards to PSLR angle: (1) reduced extensibility (PSLR 80°, n = 22). Results The ANOVA analysis showed significant differences among groups for thoracic (p Conclusions The hamstring muscle extensibility influences the thoracic and pelvic postures when maximal trunk flexion was performed. A systematic stretching programme to improve hamstring extensibility should be incorporated to training activities.

Is ‘ideal’ sitting posture real?: Measurement of spinal curves in four sitting postures

There is a lack of quantitative evidence for spinal postures that are advocated as ‘ideal’ in clinical ergonomics for sitting. This study quantified surface spinal curves and examined whether subjects could imitate clinically ‘ideal’ directions of spinal curve at thoraco-lumbar and lumbar regions: (i) flat – at both regions (ii) long lordosis – lordotic at both regions (iii) short lordosis – thoracic kyphosis and lumbar lordosis. Ten healthy male subjects had 3-D motion sensors adhered to the skin so that sagittal spinal curves were represented by angles at thoracic (lines between T1–T5 and T5–T10), thoraco-lumbar (T5–T10 and T10–L3) and lumbar regions (T10–L3 and L3–S2). Subjects attempted to imitate pictures of spinal curves for the flat, long lordosis, short lordosis and a slumped posture, and were then given feedback/manual facilitation to achieve the postures. Repeated measures analysis of variance was used to compare spinal angles between posture and facilitation conditions. Results show that although subjects imitated postures with the same curve direction at thoraco-lumbar and lumbar regions ( slumped, flat or long lordosis), they required feedback/manual facilitation to differentiate the regional curves for the short lordosis posture. Further study is needed to determine whether the clinically proposed ‘ideal’ postures provide clinical advantages.

Clichés simples du rachis : statique et relations entre rachis et bassin

Man, with his erect posture, evolves in a world subject to the laws of gravity. His spine reflects these constraints. The morphology and static of human spine and biomechanical relationships between spine and pelvis are in direct relation with bipedia. Owing to this position the pelvis widened and straightened, characteristic sagittal spinal curves appeared and the perispinal muscles were deeply reorganized. Each pelvis is characterized by an important anatomical landmark: the pelvic incidence that reflects the sagittal morphology of the pelvis. Based on this anatomical characteristic, a chain of reactions determines the more efficient equilibrium of the whole body in the sagittal plane in term of energy consumption. Incidence affects the sacral slope, which determines lumbar lordosis, which itself influences pelvic tilt, thoracic kyphosis, and even hip and knee position. All these landmarks can easily be studied on a sagittal radiograph. Knowledge of these functional relationships is essential to understand the origin of low back pain, sagittal imbalance and above all before surgical treatment of spine disorders especially when arthrodesis is considered.

Flattening of sagittal spinal curvature as a predictor of vertebral fracture

In a 12-year prospective study of 100 adult volunteers, incident vertebral fractures were analyzed for potential predictors. Decreased sagittal spinal curvature and pre-existing fractures were identified as independent predictors. The risk of vertebral fracture increased to 8.6-fold with a 1 SD decrease in both thoracic and lumbar curves. Physiological spinal curvature acts as a shock absorber: however, it has not been demonstrated whether reduced spinal curvature is a risk of vertebral fracture. The aim of this prospective study is to assess the relationship between the extent of sagittal spinal curvature and incidence of vertebral fractures. One hundred community-based volunteers aged 50+ years were followed radiologically for at least 10 years. Entire spine radiograms of volunteers in erect position were used for evaluating sagittal spinal curvatures, grade of osteoporosis, and incident vertebral fractures. Mean baseline age was 61.9 years and mean follow-up period was 12.0 years. In multivariate analysis, preexisting vertebral fracture (relative risk [RR] 3.70, 95% confidence interval [CI] 1.22-11.20), and a decrease in either thoracic or lumbar curvature by 1-SD (RR 3.06, 95% CI 1.04-9.00) were independent predictors. The fracture risk even increased in the presence of a 1-SD decrease in both thoracic and lumbar curvature (RR 8.64, 95% CI 1.39-53.78). Reduction of physiological curvatures in both thoracic and lumbar spine led to the increased risk of vertebral fracture by more than eightfold. The importance of evaluating sagittal spinal alignment should be emphasized, because it might indicate the risk of the first vertebral fracture, which is another strong predictor of subsequent fractures.

Gravitational forces and sagittal shape of the spine

The sagittal morphology of the pelvis determines the amount of lordosis needed for each individual. The proper harmony of the sagittal spinal curves allows a stable balance, economical in terms of mechanical effects and muscular energy. A previous barycentremetrical laboratory study allowed us to demonstrate that the axis of gravity of the upper body segment was located behind the lumbar vertebrae and the femoral heads, thus ensuring economy and stability. The determination of the anatomical connection of the individual gravity is thus of primary importance for the evaluation of sagittal balance. Data for 42 patients without spinal pathology, previously evaluated by barycentremetry, were used to establish a predictive equation for the application point of the gravity at the level of the third lumbar vertebra (L3). This equation, using anthropometric and radiographic pelvic and spinal parameters, was integrated into a software program called Similibary. It was applied to the same 42 subjects. These results were compared in order to validate the method. No significant difference was observed between the two techniques. This easy-to-use tool allows a personalised evaluation of the sagittal balance of the spine, both through the evaluation of the harmonious relationship between the spinal curves and the pelvis, and through the location of gravity supported by the vertebral structures in L3.

A Novel Mathematical Model of the Sagittal Spine

Development of a mathematical model with application to a cohort of healthy volunteers. To derive a smooth mathematical function representing the sagittal spinal curve from individual vertebral elements. To generate normative data using this model. Current concepts of spinal sagittal balance center on the C7 plumb line. While elegant in its ease of use, this method oversimplifies the true complexity of the spine. If the spinal curve could be expressed as a smooth mathematical function, the ability to analyze sagittal balance would be greatly enhanced. Lateral full-length radiographs of 18 normal volunteers were examined. The posterosuperior aspect of each vertebral body was chosen as a representative point for the spinal sagittal curve. A cubic spline function was derived from these points. From this function, the area under the curve (AUC) and average sagittal positions of the thoracic, lumbar, and thoracolumbar segments were calculated. Assuming an average vertebral column height of 60 cm with anterior being positive, the average position of the posterosuperior aspect of C7 relative to S1 was -2.8 cm (+/-3.0). The average thoracolumbar AUC was -161 cm2 (+/-83). The average lumbar and thoracic AUCs were 0 cm2 (+/-17) and -157 cm2 (+/-68), respectively. The average sagittal position over the thoracolumbar curve was -3.3 cm (+/-1.7). The average sagittal positions of the lumbar and thoracic subcurves were 0.1 cm (+/-1.1) and -5.1 cm (+/-2.2), respectively. Intraobserver and interobserver reliabilities were excellent. A mathematical model of the sagittal spine that retains the spine's segmental nuances was derived using cubic spline interpolation. The average sagittal position of the thoracolumbar spine, a calculation based on the AUC, is a less variable measure of sagittal balance than the C7 plumb line. The model and normative data generated from it will allow more insightful investigations of spinal deformity and more quantitative evaluations of corrective outcomes.

Computerized Assessment of Sagittal Curvatures of the Spine

The tangent circles technique has been proposed as an alternative to the Cobb angle technique to assess sagittal curves of the spine. However, it has never been compared directly to the Cobb technique. This study compares the reproducibility and clinical relevance of the maximum Cobb angle and tangent circles techniques. Standing sagittal radiographs of the spine of 10 adolescents with idiopathic scoliosis, 10 adolescents with spondylolisthesis, and 10 healthy adolescents were used. Thoracic kyphosis (TK) and lumbar lordosis (LL) were measured by 3 observers using the maximum Cobb angle and the tangent circles techniques. Intra- and interobserver intraclass correlation coefficients (ICCs) were calculated. Intra- and interobserver ICCs for TK were 0.88 and 0.85, respectively, for the maximum Cobb angle technique, and 0.94 and 0.83, respectively, for the tangent circles technique. Intra- and interobserver ICCs for LL were 0.97 and 0.77, respectively, for the maximum Cobb angle technique, and 0.88 and 0.94, respectively, for the tangent circles technique. The 2 techniques were highly correlated for the measurement of the TK (r=0.93) and LL (r=0.88). Both techniques provide excellent intra- and interobserver reproducibility. Tangent circles technique may be a good alternative to the Cobb angle technique because it allows the evaluation of the global geometry of sagittal spinal curves, especially when there is limited visibility of bony structures on radiographs.

A Prospective Study of De Novo Scoliosis in a Community Based Cohort

A 12-year prospective study of de novo scoliosis in a community based cohort. OBJECTIVE.: To investigate factors associated with development of de novo scoliosis. De novo scoliosis is becoming one of the most prevalent findings in the aging spine, and this condition is associated not only with severe back or leg symptoms but also with complicated surgical outcomes. Cross-sectional studies were limited in distinguishing de novo scoliosis from preexisting deformities, and there had been controversies over the etiology of degenerative scoliosis. Community based volunteers were recruited, then examined by orthopedic physicians. Radiologic measurements using entire spine radiographs included the angle of scoliosis and sagittal spinal curvatures, sagittal spinal balance, grade of bone atrophy, number of degenerated discs, and vertebral fractures. We defined radiologic parameters, the disc index, and lateral osteophyte difference to evaluate the asymmetrical spinal degeneration. A total of 60 subjects aged 50-84 years and without scoliosis at baseline were selected and followed for a mean of 12.0 years. De novo scoliosis >or=10 degrees developed in 22 subjects, and logistic regression analysis revealed that the baseline disc index and lateral osteophyte difference values were independent predictors (P < 0.05). Incidence of de novo scoliosis was predictable by assessing asymmetric disc degeneration in frontal radiograph. More than 20% decrease in unilateral disc height or more than 5 mm longer osteophyte on one side led to increased incidence of de novo scoliosis, which might also influence long-term results of spinal surgery.

Backpacks, Back Pain, Sagittal Spinal Curves and Trunk Alignment in Adolescents

Cross-sectional study using logistic and multinomial logistic analysis. To investigate the influence of backpack carrying on spinal profile shoulder and trunk. No similar investigations. A randomly selected sample of 1263 students aged 12-18 years were asked for dorsal (DP) and low back pain (LBP) during the school period and holidays. Debrunner's Kyphometer and Scoliometer were used to measure craniocervical angle (CCA), thoracic kyphosis, lumbar lordosis, and shoulder shift (BL). Upper trunk shift from plumbline were recorded. Girls suffer from DP more often and of much more intensity pain than boys in school period and in holidays. Backpack carrying decreased CCA and changed shoulder and upper trunk shift. Asymmetrically backpack carrying increased DP and LBP. BL-shift increased DP. DP and LBP increased with coronal trunk shift. Sagittal trunk shift increased LBP. Asymmetrically carrying of backpacks increased back pain and shoulder shift in holidays. Coronal trunk shift while carrying backpacks asymmetrically increased back pain in holidays. Asymmetric backpack carrying is associated with high intensity pain. Frontal trunk shift is associated with high intensity pain. Backpack carrying, particularly asymmetrically, results in shift of upper trunk and shoulder and cervical lordosis, which furthermore seem to increase back pain in school period and holidays. Symmetric backpack carrying is recommended.

Validité et reproductibilité des mesures cliniques rachidiennes dans la spondylarthrite ankylosante

Objectives: To evaluate the validity and the reliability of the main clinical measures of mobility and sagittal spinal curves in ankylosing spondylitis (AS). Methods: Criterion validity of the measure of the distance between C7 spinous process to plumbline (dorsal kyphosis), L3-plumb line (lumbar lordosis), lumbar, dorsolumbar and dorsal mobility. The gold standard was the value obtained from lateral radiological views of the dorsal and lumbar spine in standing position and maximum flexion. The correlation between radiological and clinical measures was assessed by a Spearman correlation coefficient (SCC). The reliability was assessed for all the clinical parameters and for chin-sternum distance (flexion, extension), chin-acromion distance (rotations) and chest expansion using the intraclass correlation coefficient (ICC) and the Bland and Altman method. Were included patients with AS and needing dorsal and lumbar Xrays. Results: Twenty-two patients (21 men), 32 ± 11 year old, 51 ± 10 kg weight, with a mean duration of the disease of 120 ± 60 months. The ICC values were good or excellent for all parameters except for the measures of dorsal mobility. The validity was evaluated in 18 patients. The value of the SCC between clinical and radiological measures was good except the measures of dorsal kyphosis and dorsal mobility. Conclusion: The clinical measures of mobility and sagittal curves have metrological properties good enough to be used in the monitoring of AS mainly for the follow-up and the evaluation of the rehabilitation. The measurement of dorsal mobility should be restricted to the lower part only. Although apparently not valid the distance C7-plumbline can be used in management of AS because of its excellent reliability.

In response

To provide a rationale for active chiropractic rehabilitative treatment that extends beyond the single goal of resolution of symptomatic complaints.A manual search of available reference texts and a search of MEDLINE were collected with an emphasis on tissue healing sequelae and the role of mechanical loading on this process.The reviewed material indicates that all tissue growth and repair is influenced by mechanical loading and body posture and is positively affected by body postures that normalize/minimize adverse mechanical stresses and strains. Altered alignment of the human frame may lead to poor healing of the body tissues and eventual pathological architectural changes may occur in muscle, ligament, bone and central nervous system. Minimization of altered postural/structural loading of the human frame may take longer than resolution, or maximal reduction, of offensive symptoms. By itself, a patient's perception of pain is not a valid indicator of health.Because mechanical loading of the neuromusculoskeletal tissues plays a vital role in influencing proper growth and repair, chiropractic rehabilitative care should focus on the normalization/minimization of aberrant stresses and strains acting on spinal tissues. Manipulation alone cannot restore body postures or improve an altered sagittal spinal curve. Therefore, postural chiropractic adjustments, active exercises and stretches, resting spinal blocking procedures, extension traction and ergonomic education are deemed necessary for maximal spinal rehabilitation. Chiropractic studies that demonstrate structural improvements are sorely lacking and needed. The use of passive treatment modalities as the sole means of chiropractic intervention for the management of patients suffering with neuromusculoskeletal dysfunction no longer has a place in modern chiropractic practice after the acute phase of healing has passed.

Segmental Roentgenographic Analysis of Vertebral Inclination on Sagittal Plane in Asymptomatic versus Chronic Low Back Pain Patients

Two homogenous groups of 120 volunteers and 120 low back pain (LBP) patients, age range 20-79 years, underwent a prospective roentgenographic segmental vertebral analysis of the thoracic and lumbar spine to compare several roentgenographic parameters useful for planning spine surgery. The following roentgenographic parameters were measured: thoracic kyphosis, lumbar lordosis, sacral inclination, distal lordosis (L4-S1), inclination of each vertebra from T4-S1, and relative vertebral inclination between adjacent vertebrae. Thoracic kyphosis increased (p < 0.0001) and sacral inclination decreased (p < 0.05) with age in the control group. Increased thoracic kyphosis correlated with decreased lumbar lordosis after the sixth decade in the control group (p < 0.01), less so in the LBP group (p < 0.05). Increased thoracic kyphosis was seen more in the LBP group than in the controls, but significantly solely in the sixth decade (p < 0.01). Lumbar lordosis was more increased in the controls than in the LBP group but significantly solely in the sixth decade (p < 0.001). The L5-S1 segmental lordosis was much more in the LBP patients than in the controls (p < 0.001). Lumbar lordosis was strongly correlated with sacral inclination in both groups (p < 0.0001) and it was significantly greater in the controls, particularly in the sixth decade (p < 0.001). Sacral inclination was significantly more in the female than in male volunteers (p < 0.05). Distal lordosis (L4-S1) represents 55% and 49% of total lumbar lordosis in controls and low back patients, respectively. Spine surgeons frequently deal with sagittal spinal deformities and the deviations of sagittal spinal curvatures and vertebral inclination in the sagittal plane, both in normal subjects and LBP patients should be clinically helpful.

Segmental patterns of sagittal spinal curvatures in children screened for scoliosis: Kyphotic angulation at the thoracolumbar region and the mortice joint

AbstractThis paper reports a segmental analysis of the lateral spinal radiographs of 37 children referred to hospital in a school screening study of 4,890 school children aged 12–13 years. On each lateral radiograph a line was drawn along the posterior surface of each vertebral body from T5‐L5 and the angle of this line from the vertical was recorded.After measuring the scoliosis curve (Cobb) angle and using conventional criteria for diagnosis, three groups of patients are defined, namely, 1) a control group (average scoliosis curve angle (Cobb) of 5°, n = 14), 2) a group with lumbar curves (average Cobb angle 21°, n = 7), and 3) a group with thoracic curves (average Cobb angle 19 degrees, n = 10). Individual lateral spinal profiles are also analyzed.The findings show: (1) In the control group, there are different degrees of vertical backward tilt (declivity) from T7–L3, with a maximum tilt at T12 (mean 26°). The most vertical vertebrae are T6 and L4, with forward tilting (proclivity) at each of (T5 and L5.2) In the lumbar curve group, the segmental sagittal tilt is not significantly different from that in the control group. The mean declivity at T12 is 25°. (3) In the thoracic curve group, the segmental sagittal tilt is significantly less than that in the control group at each of T10–L1. The mean declivity at T12 is 17°. A more vertical T12 is associated with a larger Cobb angle. (4) The individual sagittal spinal profiles of the thoracic curve group (but no other group) show lordosis in the region of the lateral spinal curve (scoliosis) and a kyphotic angulation at an average of three vertebrae below the apical vertebrae of the scoliosis curve. (5) It is suggested that as a thoracic lordoscoliosis develops, the appearance of a kyphotic angulation in the thoracolumbar and upper lumbar spine is determined by the compressibility of each disc in relation to the length of the articular processes at the corresponding level. Where the combination of disc weakness to facet length is most adverse, forward flexion occurs, as in a spinal fracture, to produce the kyphotic angulation. © 1992 Wiley‐Liss, Inc.

A comparison of radiographic and computer-assisted measurements of thoracic and thoracolumbar sagittal curvature

Sagittal plane curve characteristics of the thoracolumbar spine were evaluated from 286 lateral chest radiographs comparing the Cobb technique with a computer-aided digitizer. Thoracic kyphosis and curve apex were measured from the T3 to T11 segments, and in 120 cases, the level of the thoracolumbar curve inflexion point was determined. An age-related increase in curve magnitude was similar for both measurements, although computer generated kyphosis angles were generally larger. The apex of thoracic kyphosis was consistently located near T7 for males compared with greater variability with age for females. The thoracolumbar inflexion point shifted caudally with increasing years, being most marked for females. The computer method was more reliable, producing a coefficient of variation of 1.4% on repeated measurement. The ability to describe quantitatively the thoracolumbar curve characteristics, calculate angles between selected segments, determine points of inflexion and maximum curvature, indicates that radiographic evaluation of sagittal spinal curvature is improved with the use of computer-aided measurement.

Increased spinal mobility in adolescents with bronchial asthma

Spinal mobility was measured in thirty-five adolescents (21 boys and 14 girls) with bronchial asthma. Comparisons were carried out with an equal number of healthy controls matched for sex, age, weight, and height. Thoracic spinal movements of rotation and lateral flexion in girls and of rotation in boys were significantly greater in asthmatics as were the sagittal lumbar movements with the exception of forward flexion in the boys. Sagittal spinal curvatures of the asthmatics did not significantly differ from those of the controls. The results indicate that there are no need of explicit mobilization of thoracic spine in asthmatic children.