Changes In Sagittal Profile Research Articles

Change in sagittal profile after implantation of anchored interbody cage in the surgical procedure for degenerative cervical spine disease.

The aim of this study was to verify the relationship between changes in the segmental sagittal profile (SSP) and changes in the global sagittal profile (GSP) after anterior cervical discectomy with anchored cage implantation (ACDF). Prospective study with 2-year follow-up. This study includes 104 patients after 1-level or 2-level ACDF operated between the May 2013 and March 2016. SSP was evaluated by Cobb angle measurement of operated motion segment (CobbS) and GSP was evaluated by Cobb angle measurement in C2-C7 segments (CobbG). Both SSP and GSP were measured pre- and postoperatively within a 24 months follow-up period. The influence of factors such as age, gender, number of treated segments and osteoporosis was evaluated using t-tests. The correlation between SSP and GSP changes was assessed by Pearson's correlation coefficient. In the early postoperative period after 1-level ACDF, there was a significantly greater increase in CobbS compared to that of the 2-level ACDF (P=0.0149). Male patients experienced a significant decrease of CobbG during the first 6 months after surgery as well as patients with osteoporosis within 12 months after ACDF. After ACDF the SSP change weakly correlated with the GSP change. SSP change after 1- or 2-level ACDF correlates mostly weakly with GSP change. Male gender and osteoporosis were identified as risk factors for global lordotisation following ACDF.

Cerebral circulatory arrest detected by insonation of extracranial arteries

Most of the papers correlate sagittal radiographic parameters with health-related quality of life (HRQOL) scores for patients with scoliosis. However, we do not know how changes in sagittal profile influence clinical outcomes after surgery in adult population operated for mainly frontal deformity.This study aimed to analyze spinal sagittal profile in a population operated on adult idiopathic scoliosis (AS) and to describe variations in sagittal parameters after surgery and the association between those variations and clinical outcomes.This is a historical cohort study.We included in this study 40 patients operated on AS, older than 40 at the time of surgery (mean age 54.9), and with more than 2-year follow-up (mean 7.4 years).Full-length free-standing radiographs, Scoliosis Research Society 22 (SRS22) and Short Form 36 (SF36) instruments, and satisfaction with outcomes were available at final follow-up.Sagittal preoperative and final follow-up radiographic parameters, radiographic correlation with HRQOL scores at final follow-up, and association between satisfaction and changes in sagittal profile were analyzed. A multivariate analysis was performed. No funds were received for this article.Preoperatively, the spinal sagittal plane tended to exhibit kyphosis. Most sagittal parameters did not improve at final follow-up with respect to preoperative values. We saw, after univariate analysis, that worse sagittal profile leads to worse HRQOL, but after multivariate analysis, only spinal tilt (ST) persisted as possible predictor for worse SRS activity scores. Frontal Cobb significantly improved. Most patients (82%) were satisfied with final outcomes. Variations in sagittal profile parameters did not differ between satisfied and dissatisfied patients.Although most sagittal plane parameters did not improve after surgery, surgical treatment in AS achieves a high satisfaction rate. Good clinical results do not correlate with improving sagittal plane parameters. Sagittal profile measurements are not helpful to decide surgical treatment in patients with mainly frontal deformity.

Preoperative and postoperative sagittal plane analysis in adult idiopathic scoliosis in patients older than 40 years of age

Background ContextMost of the papers correlate sagittal radiographic parameters with health-related quality of life (HRQOL) scores for patients with scoliosis. However, we do not know how changes in sagittal profile influence clinical outcomes after surgery in adult population operated for mainly frontal deformity. PurposeThis study aimed to analyze spinal sagittal profile in a population operated on adult idiopathic scoliosis (AS) and to describe variations in sagittal parameters after surgery and the association between those variations and clinical outcomes. Design/SettingThis is a historical cohort study. Patient SampleWe included in this study 40 patients operated on AS, older than 40 at the time of surgery (mean age 54.9), and with more than 2-year follow-up (mean 7.4 years). Outcome MeasuresFull-length free-standing radiographs, Scoliosis Research Society 22 (SRS22) and Short Form 36 (SF36) instruments, and satisfaction with outcomes were available at final follow-up. MethodsSagittal preoperative and final follow-up radiographic parameters, radiographic correlation with HRQOL scores at final follow-up, and association between satisfaction and changes in sagittal profile were analyzed. A multivariate analysis was performed. No funds were received for this article. ResultsPreoperatively, the spinal sagittal plane tended to exhibit kyphosis. Most sagittal parameters did not improve at final follow-up with respect to preoperative values. We saw, after univariate analysis, that worse sagittal profile leads to worse HRQOL, but after multivariate analysis, only spinal tilt (ST) persisted as possible predictor for worse SRS activity scores. Frontal Cobb significantly improved. Most patients (82%) were satisfied with final outcomes. Variations in sagittal profile parameters did not differ between satisfied and dissatisfied patients. ConclusionsAlthough most sagittal plane parameters did not improve after surgery, surgical treatment in AS achieves a high satisfaction rate. Good clinical results do not correlate with improving sagittal plane parameters. Sagittal profile measurements are not helpful to decide surgical treatment in patients with mainly frontal deformity.

Pre- and post-operative sagittal balance in idiopathic scoliosis: a comparison over the ages of two cohorts of 132 adolescents and 52 adults

Retrospective study of a prospective clinical and radiological database of subjects with adolescent (AIS) and adult (AS) idiopathic scoliosis undergoing surgical correction by posterior approach. To evaluate the differences in sagittal alignment of the spine and pelvis in AIS and AS before surgery and changes after surgery in both populations. The relationship between the spine and pelvis highly influences the sagittal balance in adults and adolescents. However, the sagittal alignment of the spine and pelvis before and after surgery in idiopathic scoliosis, whatever the age, is poorly defined in the literature. Clinical and radiological data were extracted from a prospective database of 132 AIS patients and 52 AS before and at last follow-up after surgical correction. Sagittal parameters were evaluated on AP and lateral radiographs using a custom software: pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), thoracic kyphosis (TK), C7 Barrey's ratio, spino-sacral angle (SSA). A new algorithm of combination of balance parameters was proposed to characterize and compare the various pathological spino-pelvic settings. Based on PI subdivision in high (<55°) and low values (>55°), then on a range of PT indexed on PI giving the pelvis positioning (anteverted, normal or retroverted), the population was finally characterized by the C7 plumbline position with regard to the posterior edge of the sacrum and the center of the femoral heads, in balanced, slightly unbalanced and unbalanced. More specifically, the AIS study included the cervical shape alignment with cervical lordosis (CL) and sagittal thoracic profile assessment (hypo vs. normokyphotic). In AS, the study focused on thoraco-lumbar kyphosis (TLK) occurrence (LL length). Paired Student t tests were used for comparison (α=0.02). Pre-operatively, in AIS there was a prevalence of lower PI (57%). Whatever the PI, PT remained anteverted or normal. Positioning of C7 was much more unbalanced, forward of the femoral heads (50%), than in asymptomatic population (17%). There was a notable loss and reversal of cervical lordosis in the majority of subjects, with an average cervical kyphosis measurement of 10±18°. Thoracic kyphosis values were lower than average, while lumbar lordosis values were within normal limits. After surgery, in the entire group, a slight but significant increase of PT coupled to a decrease of SS and LL was noted, while no changes could be documented in thoracic kyphosis and cervical lordosis. However, when sub-classified according to thoracic hypo versus normokyphosis pre-op, there was a significant decrease of TK coupled to a decrease of LL and CL in the normokyphotic group, while TK and CL were improved in the hypokyphotic group. A significant number of patients improved their global balance. Changes in sagittal profile between Lenke curve types were minimal. In AS there were significant differences between low and high PI populations. Severity of unbalance increased in high PI population with association of retroverted pelvis and forward unbalance. In lower PI, increasing PT was generally sufficient to balance the patients. The occurrence of TLK was strongly increased in the entire population and became the rule in those with lower PI (76%). Post-operatively, in those with high PI, PT did not change while global balance improved slightly. The strategy of correction in higher PI was to maintain TLK. In those with low PI, PT improved while C7 did not change. Correction of TLK was obtained in eight cases. A decrease of cervical lordosis and thoracic kyphosis is commonly associated with AIS. The anterior unbalance frequently found in AIS does not seem to have the same significance of severity as in AS. In AIS PI does not change the balance criterions, while in AS the severity of unbalance is increased with higher PI. TLK seems to be a way of worsening the balance in elderly, mainly in lumbar and thoraco-lumbar scoliosis with low PI. Surgical correction of the thoracic and lumbar spine in AIS induces significant changes in the sagittal spino-pelvic profile. Changes in the cervical sagittal profile vary according to the pre-op sagittal profile of the thoracic kyphosis. Cervical lordosis and thoracic kyphosis are improved by surgical correction in subjects with pre-operative hypokyphosis, but a reverse effect is noted in those with normal pre-operative kyphosis. The clinical significance of these changes in sagittal shape remains to be determined. In AS, it appears easier to restore a good balance in the lower PI population than in those with less pre-operative unbalance.

Sagittal alignment of the cervical spine after neck injury

The normal sagittal alignment of the cervical spine is lordotic and is affected by the posture of the head and neck. The question of whether loss of cervical lordosis is the result of muscle spasm after injury or a normal variation, and the clinical significance of such changes in sagittal profile of the cervical spine has been an issue of several studies. The purpose of this paper is to study the incidence of normal cervical lordosis and its changes after neck injury compared to the healthy population. We studied the lateral radiographs of the cervical spine of 60 patients with neck injury compared to 100 patients without a neck injury. Lateral radiographs were obtained in the standing or sitting position, and the curvature of the cervical spine was measured using the angle formed between the inferior end plates of the C2 and C7 vertebrae. In the patients without neck injury, lordotic and straight cervical spine sagittal alignment was observed in 36.5% each, double curvature in 17%, and kyphotic in 10%. In the patients with neck injury, lordotic sagittal alignment was observed in 36%, straight in 34%, double curvature in 26% and kyphotic in 4%. No significant difference between the two groups regarding all types of sagittal alignment of the cervical spine was found (p > 0.100). The alterations in normal cervical lordosis in patients with neck injury must be considered coincidental. These alterations should not be associated with muscle spasm caused by neck pain.

Height Change Caused by Creep in Intervertebral Discs

Changes in spinal column height have been observed in response to different stress environments including vibration, gravity inversion, space flight, traction, and increased loading. Alterations in spinal height are dependent on body forces, externally applied forces, and properties of the discs and are considered relevant to understanding the normal and pathologic behavior of the spine. This study presents a sagittal plane, viscoelastic model of the spine that quantified the height change behavior of the human spine subjected to axial compressive forces similar to those experienced during quiet standing. The two-dimensional spine model was idealized as a collection of 23 rigid vertebral bodies and 23 deformable intervertebral discs. Time-dependent height losses were modeled using axial compressive creep material properties based on in vitro measurements obtained from the literature. The model demonstrated an instantaneous loss in height of 11.7 mm (0.67% of body height) and a height loss of 19.6 mm (1.1% of body height) at the end of 8 h. Changes in sagittal profile were estimated to contribute to 12% of the overall height loss after 8 hours. Discs in the lumbar region lost the most height, but the contribution of the lumbar region to the total height loss was 32%. The height loss contribution of the thoracic region was higher (57%), presumably because of the increased number of discs contributing to the total height loss in this region. For degenerated discs, the model predicted a similar instantaneous height loss but a 28% greater height loss after 8 h. These results suggest that the majority of spinal height loss is a direct result of intervertebral disc deformation and about two thirds of the total height loss occurs immediately on axial loading of the spine. Based on these findings, diurnal height changes in the spine are predicted to be much greater than previously believed.