Sagittal Profile Research Articles

Sagittale Balance und Kompensationsmechanismen nach operativer Versorgung bei idiopathischer Skoliose mittels segmentaler Pedikelschraubeninstrumentation

Previous studies have demonstrated good ability to improve the sagittal profile with the use of segmental instrumentation for adolescent idiopathic scoliosis (AIS) by analysing the sagittal vertical axis (SVA). However, several authors recommend analysing the spinopelvic relation in addition to the SVA. While compensatory mechanisms may neutralise a positive SVA, these mechanisms are energy consuming and may lead to unphysiological biomechanics, which can negatively influence the quality of life. The purpose of this radiographic analysis was to analyse global sagittal balance and to identify potential compensatory mechanisms after segmental instrumentation for AIS. From a prospectively collected multicentre database, patients with segmental instrumentation for AIS and a minimum follow-up of 2 years were identified. An additional inclusion criterion was the ability to measure lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), and SVA on each X-ray (preoperative, 1st erect, and the 2-year follow-up visits). LL was analysed in relation to PI in order to identify iatrogenic changes. Changes in LL were correlated to changes in PT and SVA. 91 patients were included. On the 1st erect X-ray, LL significantly decreased from pre-op but the SVA remained stable due to a significant increase of PT. At two years follow-up, PT recurred to preoperative values, accompanied by a significant increase of SVA despite a compensatory hyperlordosis below the instrumentation. The temporary increase of PT on the 1st erect was significantly correlated to an iatrogenic decrease of LL. An iatrogenic decrease of LL was significantly correlated to an increase of SVA on the 1st erect and at 2 years follow-up. An iatrogenic decrease of LL after segmental instrumentation for AIS is initially compensated for by pelvic retroversion and later by a hyperlordosis below the instrumentation.

Back pain during growth

It is wrong to believe that back pain only burdens adults: the yearly incidence during growth ranges from 10-20%, continuously increasing from childhood to adolescence. Rapid growth-related muscular dysbalance and insufficiency, poor physical condition in an increasingly sedentary adolescent community or - vice versa - high level sports activities, account for the most prevalent functional pain syndromes. In contrast to adults the correlation of radiographic findings with pain is high: the younger the patient, the higher the probability to establish a rare morphologic cause such as benign or malignant tumours, congenital malformations and infections. In children younger than 5 years old, the likelihood is more than 50%. The following red flags should lower the threshold for a quick in-depth analysis of the problem: Age of the patient <5 years, acute trauma, functional limitation for daily activities, irradiating pain, loss of weight, duration >4 weeks, history of tumour, exposition to tuberculosis, night pain and fever. High level sport equals a biomechanical field test which reveals the biologic individual response of the growing spine to the sports-related forces. Symptomatic or asymptomatic inhibitory or stimulatory growth disturbances like Scheuermann disease, scoliosis or fatigue fractures represent the most frequent pathomorphologies. They usually occur at the disk-growth plate compound: intraspongious disk herniation, diminuition of anterior growth with vertebral wedging and apophyseal ring fractures often occur when the biomechanical impacts exceed the mechanical resistance of the cartilaginous endplates. Spondylolysis is a benign condition which rarely becomes symptomatic and responds well to conservative measures. Associated slippage of L5 on S1 is frequent but rarely progresses. The pubertal spinal growth spurt is the main risk factor for further slippage, whereas sports activity - even at a high level - is not. Therefore, the athlete should only be precluded from training if pain persists or in case of high grade slips. Perturbance of the sagittal profile with increase of lumbar lordosis, flattening of the thoracic spine and retroflexion of the pelvis with hamstrings contractures are strong signs for a grade IV olisthesis or spondyloptosis with subsequent lumbosacral kyphosis. Idiopathic scoliosis is not related to pain unless it is a marked (thoraco-) lumbar curve or if there is an underlying spinal cord pathology. Chronic back pain is an under recognised entity characterised by its duration (>3 months or recurrence within 3 months) and its social impacts such as isolation and absence from school or work. It represents an independent disease, uncoupled from any initial trigger. Multimodal therapeutic strategies are more successful than isolated, somatising orthopaedic treatment. Primary and secondary preventive active measures for the physically passive adolescents, regular sports medical check-up's for the young high level athletes, the awareness for the rare but potentially disastrous pathologies and the recognition of chronic pain syndromes are the cornerstones for successful treatment of back pain during growth.

Analysis of Sagittal Spinal Alignment in 181 Asymptomatic Children

A cross-sectional study. To determine the "normal" radiographic parameters of the sagittal profile of the spine in asymptomatic children. There was consensus that cervical kyphosis is pathologic, but we suspected that the cervical kyphosis or loss of cervical lordosis is abnormal in asymptomatic children and adolescents. And we measured the pediatric sagittal profiles including the cervical lordosis for asymptomatic subjects. Analysis of 181 children without spinal pathology was performed. Radiographic measurements consisted of the following: cervical lordosis; thoracic kyphosis; thoracolumbar sagittal angle; thoracic apex; lumbar apex; lumbar lordosis; sacral inclination; sacral slope; pelvic tilt; and sagittal vertebral axis. The mean cervical lordosis was -4.8 ± 12.0 degrees (negative = lordotic), sagittal vertebral axis -2.1 ± 2.4 cm, thoracic kyphosis +33.2 ± 9.0 degrees, thoracolumbar sagittal angle 5.6 ± 8.4 degrees, lumbar lordosis -48.8 ± 9.0 degrees, sacral inclination 43.9 ± 7.6 degrees, sacral slope 34.9 ± 6.6 degrees, and pelvic tilt 9.4 ± 6.1 degrees. One hundred nine (60.2%) patients had hypolordotic cervical spine (≥ -5 degrees). Cervical kyphosis was present in 80 (44.2%) patients. There is significant variability in sagittal profile of the cervical spine in asymptomatic children. Cervical kyphosis was found in approximately 40% of our study cohort.

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.

Relationship between clinical results and sagittal profile in adult scoliosis. Value of the spinal-sacral angle and the spinal inclination angle

ObjectivesTo assess the clinical validity of two new recently described parameters (spinal-sacral angle (SSA) and spinal inclination angle (SIA)) in adult scoliosis (AS) for evaluating the spinal-pelvic sagittal profile, as well as their still undefined role in AS. Material and methodA non-concurrent prospective radiographic and clinical study was conducted on 59 primary surgeries of AS (Cobb>40°), with a minimum of 2 years follow-up. The available X-rays and health questionnaires of 49 patients were used in the study. The changes in X-ray parameters after surgery were evaluated (Wilcoxon test), as well as the correlations as regards the clinical-radiography-age parameters (Spearman test and multiple linear regression). ResultsThe median post-surgical follow-up was 8.5 years, and the median age of the patients was 49.5 years. There was a statistically significant change with the surgery in the SSA and SIA (less than 5° in both), thoracic kyphosis, lumbar lordosis (LL), pelvic rotation, sagittal balance (SB) and frontal Cobb. There was no correlation between pain and SSA-ST. There was a significant relationship between activity and SSA, ST, LL, SB, and age. After the multivariate analysis only age (not SSA or SIA) remained as a possible predictor of lower activity. DiscussionWhen frontal deformity predominates, the sagittal radiographic parameters, including the newest angles, although they have an influence patient activity when analysed individually, they lose this influence when they are analysed together and with other clinical parameters. ConclusionsThe SSA and SIA hardly change with surgery. They only correlate with activity, but cannot be considered predictors of this. Thus they do seem to be useful measurements in AS.

Correlación de resultados clínicos y perfil sagital en escoliosis del adulto. Valor del ángulo espinosacro y del ángulo de inclinación del raquis

ObjectivesTo assess the clinical validity of two new recently described parameters (spinal-sacral angle (SSA) and spinal inclination angle (SIA) in adult scoliosis (AS) for evaluating the spinal-pelvic sagittal profile, as well as their still undefined role in AS. Material and methodA non-concurrent prospective radiographic and clinical study was conducted on 59 primary surgeries of AS (Cobb>40°), with a minimum of 2 years follow-up. The available X-rays and health questionnaires of 49 patients were used in the study. The changes in X-ray parameters after surgery were evaluated (Wilcoxon test), as well as the correlations as regards the clinical-radiography-age parameters (Spearman test and multiple linear regression). ResultsThe median post-surgical follow-up was 8.5 years, and the median age of the patients was 49.5 years. There was a statistically significant change with the surgery in the SSA and SIA (less than 5° in both), thoracic kyphosis, lumbar lordosis (LL), pelvic rotation, sagittal balance (SB) and frontal Cobb. There was no correlation between pain and SSA-ST. There was a significant relationship between activity and SSA, ST, LL, SB, and age. After the multivariate analysis only age (not SSA or SIA) remained as a possible predictor of lower activity. DiscussionWhen frontal deformity predominates, the sagittal radiographic parameters, including the newest angles, although they have an influence patient activity when analysed individually, they lose this influence when they are analysed together and with other clinical parameters. ConclusionsThe SSA and SIA hardly change with surgery. They only correlate with activity, but cannot be considered predictors of this. Thus they do seem to be useful measurements in AS.

Sagittal Spinal Profile and Spinopelvic Balance in Parents of Scoliotic Children, as Compared to Normal Controls

It is well known that spinal biomechanics, as well as familial predisposition, play an important role in the onset and evolution of idiopathic scoliosis. The relationship between the sagittal profile of the spine and spinal biomechanics has also been established in a number of studies. It has been suggested previously that a certain sagittal spinal configuration with implications for spinal rotational stiffness, is inherited, thus providing a possible explanation for the well-known hereditary component in adolescent idiopathic scoliosis.

CT and radiographic analysis of sagittal profile changes following thoracoscopic anterior scoliosis surgery

BackgroundPrevious studies report an increase in thoracic kyphosis after anterior approaches and a flattening of sagittal contours following posterior approaches. Difficulties with measuring sagittal parameters on radiographs are avoided with reformatted sagittal CT reconstructions due to the superior endplate clarity afforded by this imaging modality.MethodsA prospective study of 30 Lenke 1 adolescent idiopathic scoliosis (AIS) patients receiving selective thoracoscopic anterior spinal fusion (TASF) was performed. Participants had ethically approved low dose CT scans at minimum 24 months after surgery in addition to their standard care following surgery. The change in sagittal contours on supine CT was compared to standing radiographic measurements of the same patients and with previous studies. Inter-observer variability was assessed as well as whether hypokyphotic and normokyphotic patient groups responded differently to the thoracoscopic anterior approach.ResultsMean T5-12 kyphosis Cobb angle increased by 11.8 degrees and lumbar lordosis increased by 5.9 degrees on standing radiographs two years after surgery. By comparison, CT measurements of kyphosis and lordosis increased by 12.3 degrees and 7.0 degrees respectively. 95% confidence intervals for inter-observer variability of sagittal contour measurements on supine CT ranged between 5-8 degrees. TASF had a slightly greater corrective effect on patients who were hypokyphotic before surgery compared with those who were normokyphotic.ConclusionsRestoration of sagittal profile is an important goal of scoliosis surgery, but reliable measurement with radiographs suffers from poor endplate clarity. TASF significantly improves thoracic kyphosis and lumbar lordosis while preserving proximal and distal junctional alignment in thoracic AIS patients. Supine CT allows greater endplate clarity for sagittal Cobb measurements and linear relationships were found between supine CT and standing radiographic measurements. In this study, improvements in sagittal kyphosis and lordosis following surgery were in agreement with prior anterior surgery studies, and add to the current evidence suggesting that anterior correction is more capable than posterior approaches of addressing the sagittal component of both the instrumented and adjacent non instrumented segments following surgical correction of progressive Lenke 1 idiopathic scoliosis.

Postoperative Changes in Spinal Rod Contour in Adolescent Idiopathic Scoliosis

Prospective case series. To evaluate the change in spinal rod contour from before implantation to after surgical correction of thoracic curves in patients with adolescent idiopathic scoliosis. With segmental pedicle screw spinal instrumentation and vertebral derotation, many authors have reported a loss of thoracic kyphosis postoperatively. Although surgeons anticipate some flattening of the preimplantation rod contour in the sagittal plane, the magnitude of this change in shape has not been documented. The concave and convex rod shapes of 5.5-mm ultrahigh-strength steel spinal rods (200 KSI) from patients with thoracic adolescent idiopathic scoliosis (n = 27), which were contoured with benders by the surgeon, were traced prior to insertion. Postoperative (average, 5 weeks) sagittal rod shape was determined from lateral 2-dimensional radiographs. Maximal rod deflection and angle of the tangents to rod end points (Cobb) were measured. Repeated measures analysis of variance assessed differences between pre- and postoperation. The scoliosis of 55° ±14° was corrected 72% to 15° ± 5°. The preinsertion rod shapes were more kyphotic for the concave (45.6°) than for the convex (31.4°) rods. Following correction, the concave rods flattened, with decrease in deflection of 13 mm and reduction in angle of 21° (both P < 0.001). The convex rods increased 1.5 mm in deflection and 2° in angle (P < 0.01, P = 0.18). The sagittal profile was maintained postoperatively as measured from T5-T12: 19° ±14° versus 22° ± 6° (pre vs. post, P > 0.1). We found a significant difference between pre- and postoperative rod contour, particularly for concave rods. Rod overcontouring (by ~20° for concave rod) resulted in high degrees of correction without loss of sagittal alignment. The resulting deformations are likely associated with substantial in vivo deforming forces.

Idiopathic thoracolumbar/lumbar scoliosis treated with anterior correction and interbody fusion with calcium phosphate cement

To investigate the clinical outcome and fusion rate in patients with idiopathic thoracolumbar/lumbar scoliosis treated with anterior correction and interbody fusion with calcium phosphate cement. From October 2006 to March 2008, 24 cases undergoing anterior correction and interbody fusion with calcium phosphate cement were enrolled. All of them were female, with an age ranged from 12 to 25 years. The mean Cobb angle of main curve was 46° ± 5° (range, 40° - 56°) before surgery. During operation, the most proximal and distal disc spaces were filled with rib autograft, while the remaining levels were filled with calcium phosphate cement. The interbody fusion rate, coronal correction and sagittal profile reconstruction were evaluated respectively by using χ² test and t test. Interbody fusion was performed in 103 levels, including 48 levels with rib autograft and 55 levels with calcium phosphate cement. The mean follow-up period was 23.8 months (range, 12 - 33 months) in this series. At the follow-up of 6 months, fusion rate was found as 54.2% in the levels filled with rib autograft, while 50.9% in those filled with calcium phosphate cement. Solid fusion of the whole instrumented area was achieved in all cases with a minimum one-year follow-up. No instrumentation-related complications occurred. The correction rate of main curve was on an average of 76% ± 11% after surgery. A significant difference was found between preoperative and immediate postoperative value in terms of the main curve magnitude (46° ± 5° vs. 14° ± 5°, t = -26.95, P < 0.05). The correction loss of the main curve was -5.1° - 10.4° at the final follow-up. The coronal balance and lower instrumented vertebra tilting were significantly improved after operation. The thoracolumbar kyphosis was significantly reduced postoperatively (t = 3.11, P < 0.05). Satisfactory bone fusion and correction maintenance can be achieved in idiopathic thoracolumbar/lumbar scoliosis treated by anterior instrumentation combined with interbody fusion using calcium phosphate cement.

How Does Thoracic Kyphosis Affect Patient Outcomes in Growing Rod Surgery?

Retrospective review of a multicenter series. This study was conducted to specifically identify the complication rate of growing rod surgery in patients with normal (10°-40°) versus abnormal thoracic kyphosis. Surgical treatment options for progressive early onset scoliosis include spinal fusion versus growth-sparing techniques. The current most commonly employed growing rod technique involves short fusions at the foundation sites using either hooks or screws as anchors and placement of dual growing rods spanning the deformity. Although the coronal deformity in these patients has been studied extensively, the sagittal profile has received less attention as a possible factor in complication rates and patient outcomes. Out of 387 patients who underwent surgical placement of growing rods, 90 patients had complete clinical and radiographical data, with 2-year follow-up after initial surgery. Patients were categorized into 3 groups on the basis of preoperative thoracic kyphosis magnitude: less than 10° (K- group), 10°-40° (N group), and more than 40° (K+ group). Patient diagnosis, demographics, surgical information, radiographical measurements, and complication types were tabulated and analyzed. A P value of <0.05 was considered significant for all statistical tests. The K- group experienced 27 total complications including 15 general medical complications, the N group had 20 total and 4 general complications, and the K+ group had 55 total and 22 general complications. Patients in the K+ group were 3.1 times more likely to experience a complication than those in the N group, which was statistically significant (P < 0.05). When considering all types of complications, length of follow-up, T2-T5 proximal kyphosis, postoperative Cobb angle, and rod diameter were identified as confounding variables. When the confounding variables were taken into consideration in the analysis, the odds ratios were no longer significant between the N and K+ groups. Patients in the K+ group and K- group were 2.95 and 2.89 times more likely to experience a general medical complication than those in the N group, respectively (P > 0.05). The rate of implant-related complications between the groups did not reach statistical significance, although the K+ group had the most implant complications (n = 34), including 25 rod breakages in 16 patients. Syndromic patients had 2.9 times the risk of having an overall complication when compared with the entire patient series (P < 0.05). The number of patients who experienced multiple complications was higher in the K- and K+ groups than in the N group. Patients with thoracic hyperkyphosis present even more of a challenge with respect to complications, specifically implant-related complications. Our study shows that growing rod surgery in patients with kyphosis more than 40° has significantly more general and implant complications than that in patients with normal thoracic kyphosis. Implant complications were more common in hyperkyphotic (>40°) patients and increased linearly with increasing kyphosis. The most common implant complication was rod breakage. Patients with hyperkyphotic thoracic spines, particularly syndromic patients, must be monitored closely and parents should be counseled regarding the likelihood of future adverse events.

Thoracolumbar fracture reduction by percutaneous in situ contouring

Percutaneous in situ contouring is based on bilateral bending of rods on the spine, thus increasing lordosis at the fracture. It was analyzed if this technique would provide a better reduction than prone positioning and how sagittal alignment would behave. Twenty-nine patients were operated using in situ contouring and selective anterior fusion for non-neurologic A2, A3 or B2 fractures. Clinical results were assessed prospectively using visual analog scale (VAS) and Oswestry Disability Index (ODI). The radiographic deformity correction was measured by sagittal index and regional kyphosis. Sagittal balance was assessed using kyphosis, lordosis, T9 tilt, pelvic incidence, pelvic tilt and sacral slope. Posterior wall fragment reduction was evaluated by computed tomography. After 2years, VAS and ODI were comparable to the status prior to the accident. The sagittal index was 19.7° preoperatively, 5.3° after prone positioning and -1.1° after in situ contouring (p<0.001). The loss of correction was 2.4°, mainly during the first 3months. Similar observations were made for regional kyphosis. The sagittal spino-pelvic alignment was stable postoperatively. A preoperative canal obstruction ≥50% was observed in 16 patients, and the fragments migrated anteriorly in all patients. Percutaneous instrumentation and anterior fusion provides good clinical results. In situ contouring increases lordosis obtained by prone positioning. Anterior column lengthening and ligamentotaxis reduce posterior wall fragments, which decompress the canal without laminectomy. The fusion of anterior defects prevents the loss of correction and provides a stable sagittal profile. The instrumentation may be removed without damaging the paravertebral muscles and loss of correction.

Intervertebral Disk Degeneration in the Growing Spine in Patients with Tuberculosis Kyphosis Exceeding 50 Treated by Reconstruction with a Long-Length Posterior Instrumentation

Introduction The rigid angular kyphoses in the young patients with spinal TB are not only a cosmetic problem, they also lead to cardiovascular, respiratory, and neurological disorders. The correction of the deformity could be reached by combination of the debridement, anterior column reconstruction, the shortening of posterior spine, and extended posterior instrumentation. The zone of instrumentation needs to be longer than the anterior fusion for significant correction and spinal stability. Materials and Methods Total 13 children from 2.5 to 12 years with TB spondylitis of the thoracic and lumbar spine complicated by severe angular kyphosis underwent 1-day combined surgery included anterior debridement followed by cortical bone allografting and posterior osteotomy with correction and instrumentation by laminar or hybrid devises. The anterior reconstruction exceeded three segments in all cases (maximum-replacement of 10 vertebral bodies). For real deformity correction the posterior instrumented zone exceeded the length of anterior reconstruction up to 1 or 3 segments cephalad and caudad. The operations were performed under the SSEP monitoring and additionally with wake-up test-in older cases. Neither neurological nor inflammatory complications were in these patients. The normal or closed to the normal sagittal profile was reached in all cases. Follow-up period ranged from 2 till 13 years. Complete follow-up: 13 cases. All patients have annual X-ray control. There wasn't any signs of anterior pseudo-arthrosis revealed. The condition of subchondral vertebral plates and the height of intact intervertebral disks within the zone of instrumentation and disks adjacent to the instrumented spine were compared. Results Total 11 of 13 operated patients (85%) demonstrated degeneration of initially intact disks within the instrumented spine 2 years after the surgery. The signs included loss of disk height, sclerosis, and deformation of subchondral vertebral plates. Despite nobody had back pain, the main parents' complaint was the limitation of spine range of motion. We've decided to count the early symptoms of disk degeneration, the indication to remove spinal hardware having solid anterior fusion documented. There was no increase of kyphosis, excluding one case of conjunctive deformity above the instrumented spine. Conclusion The intervertebral disks degeneration within the instrumented zone is a typical side effect of prolonged posterior rigid instrumentation in growing spine. After 2 years of surgery, it occurred in a majority of pediatric patients who had been operated due to the thoracic and lumbar spinal TB complicated by kyphosis exceeded 50ø. This degeneration was not accompanied by the pain during the childhood, but it may become symptomatic in adulthood. I confirm having declared any potential conflict of interest for all authors listed on this abstract Yes Disclosure of Interest None declared

Loss of apical vertebral derotation in adolescent idiopathic scoliosis: 2-year follow-up using multi-planar reconstruction computed tomography

The objective of this study was to evaluate 2years post-surgical loss of three-dimensional correction in adolescent idiopathic scoliosis (AIS) patients using multi-planar reconstruction computed tomography (CT). Twenty-seven AIS patients treated by segmental pedicle screw (PS) constructs were included in this study. Correction in the axial plane was evaluated using the "relative apical vertebral rotation angle" (rAVR), defined as the difference between the axial rotation angles of the upper instrumented vertebra and the apical vertebra on reconstructed axial CT images. The Cobb angle of the main curve and apical vertebral translation was measured to evaluate the coronal correction. Thoracic kyphosis was also measured for the evaluation of sagittal profile. Measurements were performed before surgery, and 1week and 2years after surgery. The relationships between the correction losses and skeletal maturity, and variety of spinal constructs were also evaluated. The mean preoperative Cobb angle of the major curve was 59.1°±11.2° before and 13.0°±7.2° immediately after surgery. Two years later, the mean Cobb angle had increased significantly, to 15.5°±7.8°, with a mean correction loss of 2.5°±1.5° (p<0.001). The mean preoperative rAVR of 28.5°±8.4° was corrected to 15.8°±7.8° after surgery. It had increased significantly to 18.5±8.4 by 2years after surgery, with a mean correction loss of 2.7°±1.0° (p<0.001). The mean correction losses for both the Cobb angle and rAVR were significantly greater in the skeletally immature patients. The significant correlations were recognized between the correction losses and the proportion of multi-axial screws, and the materials of constructs. Statistically significant loss of correction in the Cobb angle and apical vertebral axial rotation angle (AVR) were recognized 2years after surgery using PS constructs. The correction losses, especially AVR, were more evident in the skeletally immature patients, and in patients treated with more multi-axial screws and with titanium constructs rather than with stainless constructs.

Sagittal profile control in patients affected by neurological scoliosis using Universal Clamps: a 4-year follow-up study

Patients affected by cerebral palsy often develop progressive scoliosis that can results in trunk instability with an impairment of both coronal and sagittal balance. The aim of this retrospective study was to demonstrate the ability of UC to control the sagittal profile in a consecutive series of patients affected by neurological scoliosis. From 2006 to 2008, 84 patients (57 F, 27 M) affected by neurological scoliosis were treated surgically. Mean age was 14 years (range 10-17). The etiology was mainly cerebral palsy. The average pre-operative Cobb angle was 73° ± 16°. Patients were divided into three groups according to the pre-operative presence of: physiological kyphosis (mean 29° ± 8°), thoracic lordosis (mean 10° ± 6°) and hyperkyphosis (51° ± 8°). A posterior access was performed in all patients using thoracic UC associated with transpedicular lumbar screws and a conventional claw at the upper extremity of the construct. The average percentage of coronal correction was 72%. In all three groups, we observed a common trend toward maintaining or restoring the physiological values. Mean follow-up time was 36 months. At the 1-year follow-up, the mean loss of correction was 7° ± 2° in the coronal plane and 2° ± 1° in the sagittal plane with no other change thereafter. The hybrid construct using UC appears effective in neurological scoliosis treatment, providing a good correction of the deformity in both coronal and sagittal planes. In the present series, physiological thoracic kyphosis has been restored in all patients, providing better sitting tolerance in wheelchair-bound patients, and retaining standing and walking abilities in ambulatory patients.

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.

Neurological L5 burst fracture: posterior decompression and lordotic fixation as treatment of choice

We report our experience and literature review concerning surgical treatment of neurological burst fractures of the fifth lumbar vertebra. Nineteen patients with L5 neurological burst fractures were consecutively enrolled; 6 patients had complete motor deficits, and 12 had sphincter dysfunction. We performed 18 posterior and one combined approaches. To avoid kyphosis, posterior internal fixation was achieved by positioning patients on the operating table with hips and knees fully extended. At the latest follow-up (mean 22 months, range 10-66), neurological recovery, canal remodeling and L4-S1 angle were evaluated. Vertebral body replacement was difficult, which therefore resulted in an oblique position of the cage. Vertebral bodies still remained deformed, even though fixation allowed for an acceptable profile (22°, range 20-35). We observed three cases of paralysis, five complete, and three incomplete recoveries. In the remaining eight patients, sphincter impairment was the only finding. In 15 patients, pain was absent or occasional; in four individuals, it was continuous but not invalidating. Remodeling was visible by X-ray and/or CT, without significant secondary stenosis. The L5 burst fractures are rare and mostly due to axial compression. Cauda and/or nerve root injuries are absolute indications for surgery. If an anterior approach is technically difficult, laminectomy can allow for decompression, and it can be easily combined with transpedicular screw fixation. Posterior instrumented fusion, also performed with the aim to restore sagittal profile, when associated with an accurate spinal canal exploration and decompression, may be looked at as an optimal treatment for neurological L5 burst fractures.

Sagittal endplate morphology of the lower lumbar spine

The sagittal profile of lumbar endplates is discrepant from current simplified disc replacement and fusion device design. Endplate concavity is symmetrical in the coronal plane but shows considerable variability in the sagittal plane, which may lead to implant-endplate mismatch. The aim of this investigation is to provide further analysis of the sagittal endplate morphology of the mid to lower lumbar spine study (L3–S1), thereby identifying the presence of common endplate shape patterns across these levels and providing morphological reference values complementing the findings of previous studies. Observational study. A total of 174 magnetic resonance imaging (MRI) scans of the adult lumbar spine from the digital archive of our centre, which met the inclusion criteria, were studied. Superior (SEP) and inferior (IEP) endplate shape was divided into flat (no concavity), oblong (homogeneous concavity) and ex-centric (inhomogeneous concavity). The concavity depth (ECD) and location of concavity apex (ECA) relative to endplate diameter of the vertebrae L3–S1 were determined. Flat endplates were only predominant at the sacrum SEP (84.5%). The L5 SEP was flat in 24.7% and all other endplates in less than 10%. The majority of endplates were concave with a clear trend of endplate shape becoming more ex-centric from L3 IEP (56.9% oblong vs. 37.4% ex-centric) to L5 IEP (4% oblong vs. 94.3% ex-centric). Ex-centric ECA were always found in the posterior half of the lumbar endplates. Both the oblong and ex-centric ECD was 2-3 mm on average with the IEP of a motion segment regularly possessing the greater depth. A sex- or age-related difference could not be found. The majority of lumbar endplates are concave, while the majority of sacral endplates are flat. An oblong and an ex-centric endplate shape can be distinguished, whereby the latter is more common at the lower lumbar levels. The apex of the concavity of ex-centric discs is located in the posterior half of the endplate and the concavity of the inferior endplate is deeper than that of the superior endplate. Based on the above, the current TDR and ALIF implant design does not sufficiently match the morphology of lumbar endplates in the sagittal plane.

Polyetheretherketone cages alone with allograft for three-level anterior cervical fusion.

A total of 25 consecutive patients suffering from degenerative cervical disc disease who underwent three-level anterior cervical discectomy and fusion (ACDF) including polyetheretherketone (PEEK) cages packed with allograft were followed up for at least two years. The fusion rate reached 72% (18/25), and asymptomatic pseudarthrosis was seen in 6 patients but without mobility on flexion-extension radiographs, and revision surgery was not needed. Cage subsidence occurred at one level (C67), but it was not progressive, and reoperation was not necessary. A significant increase (P < 0.001) in fused segment angle (FSA) and fused segment height (FSH) was observed postoperatively. Similarly, a significant clinical improvement (P < 0.001) was demonstrated postoperatively in terms of Japanese Orthopedic Association (JOA) score and visual analog scales (VASs) score. PEEK cages alone with allograft proved to be a safe and effective surgical option in the treatment of three-level degenerative cervical disc disease. Although the fusion rate was not high, this technique may offer improvement of symptomatology and maintenance of cervical spine's sagittal profile.

Different patterns of weight bearing impact sagittal spinal balance

Background A physiologic sagittal alignement of the spine with lumbar lordosis and thoracic kyphosis is the most stable position of the spine , while in patients with Idiopathic Scoliosis (IS) the sagittal profile of the spine is flattened or inversed [1,2]. It has been shown that a correction of the sagittal profile also corrects coronal plane deformity in patients with IS [1]. Therefore sagittal corrections seems to play an important role in the conservative treatment of IS. Within the ‚Best Practice’ PT program simple tools are used to correct scoliosis in 3D. One of these tools is the sagittal realignment of the scoliotic pattern of weight bearing. The impact different weight bearing (WB) patterns might have are subject of this investigation.