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OBJECTIVEThe aim of this study was to investigate sagittal alignment and compensatory mechanisms in patients with monosegmental spondylolysis (mono_lysis) and multisegmental spondylolysis (multi_lysis).METHODSA total of 453 adult patients treated for symptomatic low-grade spondylolytic spondylolisthesis were retrospectively studied at a single center. Patients were divided into 2 subgroups, the mono_lysis group and the multi_lysis group, based on the number of spondylolysis segments. A total of 158 asymptomatic healthy volunteers were enrolled in this study as the control group. Radiographic parameters measured on standing sagittal radiographs and the ratios of L4–S1 segmental lordosis (SL) to lumbar lordosis (L4–S1 SL/LL) and pelvic tilt to pelvic incidence (PT/PI) were compared between all experimental groups.RESULTSThere were 51 patients (11.3%) with a diagnosis of multi_lysis in the spondylolysis group. When compared with the control group, the spondylolysis group exhibited larger PI (p < 0.001), PT (p < 0.001), LL (p < 0.001), and L4–S1 SL (p = 0.025) and a smaller L4–S1 SL/LL ratio (p < 0.001). When analyzing the specific spondylolysis subgroups, there were no significant differences in PI, but the multi_lysis group had a higher L5 incidence (p = 0.004), PT (p = 0.018), and PT/PI ratio (p = 0.039). The multi_lysis group also had a smaller L4–S1 SL/LL ratio (p = 0.012) and greater sagittal vertical axis (p < 0.001).CONCLUSIONSA high-PI spinopelvic pattern was involved in the development of spondylolytic spondylolisthesis, and a larger L5 incidence might be associated with the occurrence of consecutive multi_lysis. Unlike patients with mono_lysis, individuals with multi_lysis were characterized by an anterior trunk, insufficiency of L4–S1 SL, and pelvic retroversion.

To analyze the factors causing failure of primary surgery in congenital scoliosis (CS) patients with single hemivertebra (SHV) undergoing posterior spinal fusion, and to elucidate the revision strategies.In this retrospective study, a total of 32 CS patients secondary to SHV undergoing revision surgery from April 2010 to December 2017 due to failed primary surgery with more than 2 years follow-up were reviewed. The reasons for failure of primary surgery and revision strategies were analyzed for each patient. The radiographic parameters including coronal Cobb angle, segmental kyphosis (SK), coronal balance (CB), and sagittal vertical axis (SVA) were compared between pre- and post-revision. The complications during revision and follow-up were recorded.The mean age at revision surgery of the 32 CS patients was 15.8 ± 9.7 years and the average duration between primary and revision surgery was 31.0 ± 35.4 months. The reasons for failed primary surgery were severe post-operative curve progression of focal scoliosis in 14 cases (43.8%), implant failure in 17 (53.1%) and trunk imbalance in 12 (37.5%). The candidate revision strategies included thorough resection of residual hemivertebra and adjacent discs, extending fusion levels, complete pseudarthrosis resection, massive bone graft, replacement of broken rods, satellite rod fixation, horizontalization of upper/lower instrumented vertebrae and rigid fusion of structural compensatory curves were performed individually. After revision surgery, the coronal Cobb angle, SK, CB and SVA showed significant improvement (P 0.05) with no significant correction loss during follow-up (P 0.05). The intra-operative complications included alarming changes of neurologic monitoring in three (9.4%) patients and dual tear in two, while rod fracture re-occurred was detected in one patient at 18 months after revision.The common reasons for failed primary surgery in CS patients with SHV undergoing posterior spinal fusion were severe post-operative curve progression of focal scoliosis, implant failure and trunk imbalance. The revision strategies including thorough resection of residual hemivertebra and adjacent discs, extended fusion levels to structural curvature, complete pseudarthrosis resection, massive bone graft, replacement of broken internal fixation and horizontalization of upper/lower instrumented vertebrae should be individualized based on the causes of failed primary surgery.

Background There was a paucity of valid information on how to rectify the convex coronal imbalance effectively in dystrophic scoliosis secondary to Type I neurofibromatosis (DS-NF1), while postoperative inadvertent aggravation of CCI occurred regularly resulting in poor patient satisfaction. We aimed to identify the risk factors for persistent postoperative CCI in DS-NF1, and to optimize the coronal rebalancing strategies based on the lessons learned from this rare case series. Methods NF1-related scoliosis database was reviewed and those with significant CCI (> 3 cm) were identified, sorted and the outcomes of surgical coronal rebalance were analyzed to identify the factors being responsible for failure of CCI correction. Results CCI with dystrophic thoracolumbar/lumbar apex was prone to remain uncorrected (7 failure cases in 11) when compared to those with thoracic apex (0 failure cases in 4) (63.6% vs. 0.0%, p = 0.077). Further comparison between those with and without post-op CCI showed a higher correction of main curve Cobb angle (65.9 ± 9.1% vs. 51.5 ± 37.3%, p = 0.040), more tilted instrumentation (10.3 ± 3.6° vs. 3.2 ± 3.1°, p = 0.001) and reverse tilt and translation of upper instrumented vertebra (UIV) to convex side (8.0 ± 2.3° vs. -3.4 ± 5.9°, p p = 0.001) in the uncorrected imbalanced group. Multiple linear regression analysis revealed that △UIV translation (pre- to post-operation) (β = 0.832; p = 0.030) was significantly correlated with the correction of CBD. Conclusion Thoracolumbar/lumbar CCI in dystrophic scoliosis was prone to suffer high risk of persistent post-op CCI. Satisfying coronal rebalance should avoid UIV tilt and translation to the convex side, tilted morphology of instrumentation and over correction maneuvers for main curve, the upper hemi-curve region in particular.

To discuss the long-term outcome of convex epiphysiodesis in the treatment for congenital scoliosis (CS).The clinical data of 22 patients with hemivertebral deformity undergoing convex epiphysiodesis from the October 1998 to Febuary 2008 were respectively analyzed. There were 12 males and 10 females. The whole spine anteroposterior radiographs were taken preoperatively, at 3-month postoperatively and at the final follow-up to measure the main curve and the compensatory curve. The progression rate was calculated for each patient. Observing the correlation between the progression rate and annual progression of the scoliosis and age, gender, hemivertebral number, hemivertebral position, preoperative main curve Cobb angle and compensatory curve Cobb angle, comparing different ages, genders, hemivertebral number and position, and preoperative main curve Cobb angle on the progression of postoperative curve.The mean Cobb angle of main curve changed from (40.5±9.8) ° before surgery to (39.5±11.1) ° at 3 months after surgery, which significantly increased to (46.8±13.9) ° in the final follow-up. Meanwhile the mean Cobb angle of compensatory curve was changed from (20.1±10.8) ° before surgery to (23.0±11.1) °, which significantly increased to (29.9±11.5) ° in the final follow-up. There were no significant differences in the Cobb angle of the main curve and the compensatory curve between postoperative 3 months and before operation (The convex epiphysiodesis technique cannot effectively prevent curve progression of CS patients in the long-term follow-up. It is not recommended to apply this technique to the treatment of patients with congenital hemivertebrae.

To compare the sagittal morphological features of the spine and pelvis between L₅S₁ dysplastic spondylolisthesis and isthmus spondylolisthesis in adolescent.Retrospective analysis of 24 cases of adolescent L₅S₁ spondylolisthesis with complete imaging data from May 2002 to December 2016. Those included 8 males and 16 females, aged from 10 to 18 years old with an average of (13.4±2.0) years. Among them, 9 cases were diagnosed as dysplastic spondylolisthesis (dysplasia group) and 15 cases isthmic spondylolisthesis (ischemic group). Radiographic parameters including slippage distance, slippage degree, slippage angle, sagittal vertical axis(SVA), thoracic kyphosis(TK), lumbar lordosis(LL), L₅ incidence(L₅I), pelvic incidence(PI), pelvic tilt(PT), sacral slope(SS), sagittal pelvic thickness(SPT), lumbosacral angle (LSA), sacral table angle (STA) were measured on the spinal lateral X-ray of the standing position. Independent-samples t-test was used in the comparison of each variable between two groups.There were no significant differences in slippage distance, slippage rate, slippage angle between two groups. In dysplasia group, SVA, L₅I, PT, SPT were (37.0±48.4) mm, (57.0±14.8)°, (42.3±15.4)°, (56.1±21.2) mm, respectively, and (-11.0±22.2) mm, (31.7±19.3) °, ( 15.5±10.2)°, (31.4±19.1) mm in ischemic group; and the differences between the two groups were significant(Significant different from isthmic spondylolisthesis, adolescents with dysplastic spondylolisthesis present a different spino-pelvic sagittal alignment, characterized with trunk forward leaning and pelvic retroversion. In case of sagittal imbalance, early surgical intervention is required to restore a balanced spino-pelvic alignment.

This paper presents a highly challenging technique involving posterior double vertebral column resections (VCRs) and satellite rods placement. This was a young adult case with severe angular thoracolumbar kyphosis of 101 degrees, secondary to anterior segmentation failure from T(11) to L(1). There were hemivertebrae at T(11) and T(12), and a wedged vertebra at L(1). He received double VCRs at T(12) and T(11) and instrumented fusion from T(6) to L(4) via a posterior only approach. Autologous grafts and a cage were placed between the bony surfaces of the osteotomy gap. Once closure of osteotomy was achieved, bilateral permanent CoCr rods were placed with addition of satellite rods. Postoperative X‐ray demonstrated marked correction of kyphosis. On the 10(th) days after surgery, the patient was able to walk without assistance. In conclusion, double VCRs are effective to correct severe angular kyphosis, and addition of satellite rods may be imperative to enhance instrumentation strength and thus prevent correction loss.

Study Design. A prospective trial of MRI study in patients with "idiopathic" left thoracic scoliosis. Objective. To investigate the prevalence of neural axis abnormalities in asymptomatic patients with "idiopathic" left thoracic scoliosis. Summary of Background Data. Some patients with neural axis abnormalities have scoliosis as the only presenting sign, and they might be given a diagnosis of "idiopathic" scoliosis. These neural axis abnormalities are risk factors for neurologic injury during spine correction. With the development of MRI, neural axis abnormalities are increasingly being found in patients with "idiopathic" scoliosis. However, there are few reports on the prevalence of neural axis abnormalities in asymptomatic patients with "idiopathic" left thoracic scoliosis. Methods. A total of 68 patients with presumed "idiopathic" left thoracic scoliosis were examined for neural axis abnormalities, using MRI. Results. Neural axis abnormalities were detected in 37 (54%) patients, including Chiari 1 malformation in 15 patients, Chiari 1 malformation with syringomyelia in 10, Chiari 1 malformation with syringomyelia and tethered cord in 1, Chiari 1 malformation with syringomyelia and diastematomyelia in 1, syringomyelia in 8, syringomyelia with tethered cord in 1, and arachnoidal cyst in cerebellomedullary cistern in 1 patient. There were statistically significant differences between patients with and without neural axis abnormalities regarding gender and curve severity (P < 0.05). Conclusion. When a left thoracic curve pattern is present in patients with "idiopathic" scoliosis, especially in male patients or patients with severe curve, strong consideration should be given to the possibility of the presence of neural axis abnormalities, and acquisition of an MRI scan considered.

To investigate the effect of sympathectomy on the development and progression of scoliosis in bipedal C57BL/6J mice model.Sixty female 3-week-old C57BL/6J mice were selected to establish bipedal scoliotic mice model after amputations of forelimbs and tails. All mice were randomly divided into three groups, 20 mice for each group. Group 1 received daily intraperitoneal injection of 0.9% saline (5 mg/kg); while Group 2 and 3 received sympathectomy by daily intraperitoneal injection of propranolol (20 mg/kg) and guanethidine sulfate (40 mg/kg), respectively. Posteroanterior X-rays were obtained at 20th week. Curves were measured using Cobb method and scoliosis was defined as a Cobb angle of10°. Incidence of scoliosis and severity of curves were compared among groups using Chi-square test and One-way analysis of variance, respectively.There were 17 (85.0%) mice presented scoliosis in Group 1; whereas 11 (55.0%) and 10 (50.0%) mice presented scoliosis in Group 2 and 3, respectively. The incidence of scoliosis was found to be higher in Group 1, and the difference was statistically significant (χ(2) = 6.172, P = 0.046). As for curve magnitudes, the mean Cobb angle was 20° ± 9° in Group 1, 10° ± 7° in Group 2, and 12° ± 8° in Group 3. The mean Cobb angle of Group 1 was significantly greater than those of Group 2 and 3 (F = 9.545, P0.001), but there was no significant difference in mean Cobb angle between Group 2 and 3.Sympathetic nervous system may be involved in the development and progression of scoliosis in bipedal C57BL/6J mice model. Sympathectomy do not seem to dramatically decrease the incidence of scoliosis, probably due to that bipedalism itself may also be a cause of scoliosis in this animal model.

To evaluate the changes of the position of medulla oblongata and cerebellum following posterior fossa decompression (PFD), and to investigate their influences on the prognosis of the syringomyelia in adolescents with Chiari malformation (CM).A retrospective review was performed on all CM patients between September 2006 and September 2011. A subset of 46 patients, including 25 male and 21 female patients, was finally enrolled according to the inclusion criteria. The initial age and duration of follow-up averaged 13.9 years (range, 10-17 years) and 13 months (range, 6-52 months), respectively. On mid-sagittal MRI, the following parameters were evaluated pre- and postoperatively (follow-up ≥ 6 months): the longitudinal and transverse position of bulbopontine sulcus, the fourth ventricle vertex, the lower extreme of cerebella tonsil, the cervico-medullary angle, the maximal syrinx/cord(S/C) ratio and the syrinx length. Changes in these parameters were analysed using the paired samples t test, and for these reaching statistical significances, an additional bivariate correlation analysis was performed to investigate their relation with syrinx resolution.At the latest follow-up, upward shifting of the bulbopontine sulcus was observed in 31 patients(67.4%), with upward shifting of the lower extreme of cerebella tonsil presenting in 35 patients(76.0%). The maximal S/C ratio and the syrinx length were significantly improved postoperatively (t = 7.114 and 7.816, P = 0.000).Significant resolution of the syrinx was demonstrated in 40 patients(86.9%), and more specifically, the average improvement rates of the maximal S/C ratio and the syrinx length were 32% ± 30%and 43% ± 33%, respectively. In addition, the bivariate correlation analysis revealed that syrinx resolution was significantly correlated with the upward shifting of the bulbopontine sulcus (r = 0.332, P = 0.027) and lower extreme of cerebella (r = 0.298, P = 0.044) .The upward shifting of the bulbopontine sulcus and the lower extreme of cerebella tonsil might be implicated in the mechanisms of postoperative syrinx resolution.

To study the relationship between T1 tilt and cosmetic shoulder balance in adolescent idiopathic scoliosis (AIS) patients.Seventy-one Lenke type 2 AIS patients were recruited into the present study from January 2010 to December 2011. There were 61 female and 10 male patients, the average age was (15.1 ± 2.9) years (range 10-18 years); the average Risser sign was 2.8 (range 1-5). The patients were photographed from the back in neutral standing position on level ground wearing underpants. Also, all the patients had a standing posterior-anterior radiograph in a relaxed standing position. The cosmetic shoulder height (CSH), which included cosmetic inner shoulder height (CSHi) and cosmetic outer shoulder height (CSHo), were measured in the photographs. Positive value was defined as left shoulder was higher than the right shoulder, and negative value was defined as right shoulder was higher than the left shoulder. CSH5 mm was defined as positive CSH, CSH-5 mm was defined as negative CSH, -5 mm ≤ CSH ≤ 5 mm was defined as leveled CSH. T1 tilts were measured in the posterior-anterior radiographs. Positive value was defined as the left proximal vertebral body up and right lower vertebral body down, and negative value was defined as the right proximal vertebral body up and left lower vertebral body down. T1 tilt5° was defined as positive T1 tilt, T1 tilt-5° was defined as negative T1 tilt, -5° ≤ T1 tilt ≤ 5° was defined as leveled T1 tilt.T1 tilt was found to be significantly correlated with CSHi and CSHo (r = 0.25 and 0.28, P0.05).For positive T1 tilt patients, there were 59.0% (36/61) patients with positive CSHo, 37.7% (23/61)with leveled CSHo, and 3.3% (2/61)with negative CSHo.For the patients with leveled T1 tilt, it was 3/10, 5/10 and 2/10.For positive T1 tilt patients, there were 83.6% (51/61) patients with positive CSHi, 11.5% (7/61) with leveled CSHi, and 4.9% (3/61) with negative CSHi; For the patients with leveled T1 tilt, it was 6/10, 2/10 and 2/10.Although positive correlation is found between T1 tilt and cosmetic shoulder balance, positive T1 tilt is not an indicator of higher left shoulder.Elevated left shoulder, leveled shoulders and elevated right shoulder are all found in positive T1 tilt patients.

OBJECTIVE: The molecular mechanism of low bone mass in girls with adolescent idiopathic scoliosis (AIS) has not been ascertained. Runx2 is a critical transcription factor regulating osteoblast differentiation and maturation. The present study aimed to explore the possible relationship between Runx2 expression in osteoblasts and bone mineral density (BMD) in subjects with AIS. METHODS: Twenty‐two girls with AIS scheduled to corrective surgery with iliac crest as donor site of autograft for spinal fusion were recruited. The BMD of lumbar spine and femoral neck were assessed by dual‐energy X‐ray absorptiometry, then patients were divided into two groups with either normal or reduced BMD. Cancellous bone was harvested from their iliac crests for primary culture of osteoblasts. mRNA and protein expression of Runx2 were assayed by reverse transcription‐polymerase chain reaction and western blotting, respectively. Results were compared between the two groups and correlated with BMD. RESULTS: AIS patients with normal BMD showed comparable maturity and body mass index but significant lower Cobb angle of main curve than those of patients with reduced BMD. The mean BMD of lumbar spine and femoral neck were 0.993 g/m(2) and 0.911 g/m(2) in patients with normal BMD, and were 0.757 g/m(2) and 0.733 g/m(2) in those with reduced BMD, respectively. The differences were significant between two groups (P < 0.05). The relative mean mRNA and protein expression of Runx2 were 0.49 ± 0.12 and 0.062 ± 0.020 in AIS with normal BMD, 0.35 ± 0.12 and 0.042 ± 0.006 in AIS with reduced BMD, respectively. Significantly lower Runx2 mRNA and protein expression were found in patients with AIS patients with reduced BMD than in those with normal BMD (P < 0.05). After controlling for age, weight and body mass index, positive correlations were found between Runx2 expression of both mRNA and protein and BMD of lumbar spine and femoral neck. CONCLUSION: The abnormal expression of Runx2 in patients with AIS and reduced BMD indicates abnormal regulation of differentiation of their osteoblasts. Runx2 may play an important role in the pathogenesis of reduced BMD in patients with AIS.

STUDY DESIGN A computed tomography study. OBJECTIVE To identify the best scoliotic deformity components that show impact upon the spontaneous postoperative modulation of the deformed anterior chest wall contour in right convex thoracic adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA Spontaneous postoperative aggravation of the anterior concave costal projection was a common occurrence in adolescent idiopathic scoliosis, yet the risk factors that effectively bridged the gap between what the surgeons did in the interior and how the rib cages reacted on the exterior were still open to debate. METHODS Pre- and postoperative computed tomographic scans of 77 patients with right convex thoracic adolescent idiopathic scoliosis were retrieved and analyzed. According to the postoperative variation of anterior chest wall angle (CWA), the patients were divided into 2 groups with either aggravated or improved CWA. Multiple scoliotic deformity parameters and their surgical correction rates were evaluated, correlated, and then compared between the 2 groups. Moreover, patients with apex located at T9 were isolated and evaluated independently. A logistic regression analysis was used to determine the independent predictors of the spontaneous postoperative modulation of the anterior chest wall contour. RESULTS The surgical correction rate of Cobb angle (supine), the rotational angle with respect to the sagittal plane (RAsag angle), the rotational angle with respect to the anterior midline of the body (RAml angle), the angle of lateral deviation of the apical vertebrae from the midline (MLdev angle), the posterior hemithorax ratio, the vertebral translation (VT), and the thoracic rotation averaged 64.6%, 19.5%, 30.8%, 39.2%, 15.0%, 41.2%, and 28.7%, respectively. Ratio of aggravated anterior chest wall contour was the highest at the T7 apex group (84.6%) as compared with T8 apex group (47.1%), T9 apex group (19.5%), and T10 apex group (0.0%). The preoperative CWA was significantly lower in the aggravated CWA group when compared with the improved group (2.1 ± 1.8°vs. 6.6 ± 2.4°, P < 0.001). Besides, in the aggravated CWA group, significantly greater surgical correction of VT and lesser correction of RAsag angle were demonstrated when compared with the improved CWA group (VT: 53.0% vs. 34.8%, P = 0.001; RAsag: 2.5% vs. 28.7%, P = 0.000). In the T9 subgroup, remarkably different correction rate of VT and RAsag were similarly observed (VT: 54.9% vs. 35.3%, P = 0.046; RAsag: 4.9% vs. 23.5%, P = 0.034). In terms of other deformity parameters, no significantly different correction rate was consistently detected. In the logistic regression analysis, apex location, CWA, and correction rate of RAsag were demonstrated to be independent factors predictive of the alteration of chest wall contour. CONCLUSION In addition to the smaller preoperative CWA and higher apex location, lesser correction of vertebral rotation, if accompanied by great surgical correction of apical VT, could also largely result in a poor postoperative anterior chest wall contour.

To explore the feasibility of single-stage skipping two-level pedicle subtraction osteotomy (PSO) for severe thoracolumbar kyphosis (Cobb100°) in advanced ankylosing spondylitis (AS).Ten AS patients with thoracolumbar kyphosis undergoing skipping two-level PSO were retrospectively reviewed. The most frequent levels of osteotomy was L1 and L4 (n = 7), followed by T12 and L3 (n = 2) and L2 and L5 (n = 1). All patients were males with a mean age of 28.5 ± 9.1 years (range: 17 - 47). The pre- and post-operative values of thoracic kyphosis (TK), lumbar lordosis (LL), globe kyphosis (GK), local kyphosis of osteotomized vertebra (LK1, LK2) and sagittal imbalance (SVA) were measured.Significant differences were observed with respects to the improvements of LL, GK, LK1, LK2 and SVA (P0.01). LL, GK, LK1, LK2 and SVA improved from 41.9°, 113.4°, 40.5°, -0.3° and 25.2 cm preoperatively to -44.1°, 71.6°, 13.5°,-26.8° and 5.8 cm postoperatively respectively. The mean operative duration was 370 minutes (range: 290 - 420) and the estimated volume of blood loss 2600 ml (range: 1700 - 3800). Dural tear occurred intra-operatively in 1 patient. One had a transient brachial plexus paralysis and resolved after 1 week postoperatively. One had transient radiculopathy in right lower extremity and recovered completely 3 weeks postoperatively.As a safe and effective technique for correction of severe thoracolumbar kyphosis (Cobb100°) secondary to AS, single-stage skipping two-level PSO osteotomy can achieve larger correction and better sagittal alignment with a mean correction of 86°in terms of LL.

To investigate the early outcome of vertical expandable prosthetic titanium rib (VEPTR) technique in treating early-onset scoliosis.This study recruited 11 early-onset scoliosis patients (8 boys and 3 girls) who received VEPTR treatment from December 2006 to July 2011 with a minimum follow-up of 12 months. The average age at initial surgery was (7 ± 3) years (range, 3.1 to 9.8 years). VEPTR device, either rib to rib or rib to lumbar, was implanted at initial surgery. During the regular post-operative follow-ups, expansion surgeries were scheduled at an interval of 6 to 12 months. Measurements of primary curve magnitude, apical vertebral translation, thoracic height and T(1)-S(1) height were performed on radiographs, and were compared between those of preoperatively, postoperatively, and at latest follow-up through paired-t tests.All patients had a mean follow-up of (32 ± 11) months. Totally 41 surgeries were performed, averagely 3.7 surgeries per patient; and 30 expansion surgeries were carried out, averagely 2.7 surgeries per patient. The average interval for each expansion surgery was 8 months. From preoperatively to latest follow-up, the Cobb angle of primary curves was averagely corrected from 78° ± 18° to 55° ± 11° (t = 4.931, P0.05), and apical vertebral translation and thoracic kyphosis displayed slight improvement. Average thoracic height increased from (13.3 ± 2.0) cm to (17.2 ± 2.4) cm (t = 8.365, P0.001), and average T(1)-S(1) height from (24.4 ± 3.8) cm to (32.5 ± 5.3) cm (t = 9.080, P0.001). After initial surgery with VEPTR instrumented, gains in thoracic height and T(1)-S(1) height per expansion surgery averaged (0.8 ± 0.3) cm and (1.8 ± 0.4) cm, respectively. Eight complications occurred in 6 patients, including rib cradle dislodgements, displayed infection, intraoperative pleura rupture and loosening of lumbar pedicle screws.VEPTR technique proves to be an effective way of preventing curve progression in early-onset scoliosis patients while allowing growth of spine and chest. Yet, indications for such a technique need to be strictly selected because of the relatively high complication rate.

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, P0.05). 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, P0.05).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.

To investigate the incidence of thoracic curve decompensation or proximal adding-on phenomenon after anterior selective fusion of thoracolumbar or lumbar curve in Lenke type 5 adolescent idiopathic scoliosis (AIS), and to identify its risk factors.From June 2001 to December 2008, 130 Lenke type 5 AIS patients with a Cobb angle of 40° - 73° treated with anterior selective thoracolumbar or lumbar fusion, and with a minimum 2-year postoperative regular follow-up were recruited in this study. The average age, Cobb angle and Risser sign of all patients was 14.8 ± 1.6 years, 46° ± 6° of major thoracolumbar or lumbar curve (TL or L), 25° ± 7° of proximal thoracic curve and 0-5, respectively. The patients were grouped according to the relationship between the upper instrumented vertebrae (UIV) and the upper end vertebrae (UEV), the patients' Risser sign and the relationship between UIV and C(7) plumb line (C(7)PL). The radiographic data of the patients were compared between patients with and without proximal adding-on by using t test, and the incidence of proximal adding-on was analyzed in terms of determination of UIV and Risser sign to identify the risk factors of this phenomenon by using Fisher's exact test.Eleven patients were identified with proximal adding-on, thus the incidence of it was 8.5%. At last follow-up postoperatively, the average Cobb angle of TL or L and proximal thoracic curve was 9° ± 4° and 11° ± 5°, respectively. Moreover, the incidence of adding-on in Rissex sign grade 0 to 1 (3/8) was higher than that of grade 2 to 3 (12.1%) and grade 4 to 5 (4.5%). In addition, the incidence of adding-on in UIV lower than UEV group (20.6%) was obviously higher than that of UIV higher than or equal to UEV group (4.2%). The incidence of adding-on for patients with C(7)PL falls away from UIV (19.5%) were obviously higher than that of patients with C(7)PL falls between the pedicle and lateral margin of UIV (3.6%) and between bilateral pedicles of UIV (3.0%). Each group showed significant difference for the incidence of adding-on by Fisher's exact test (P0.05).There exists the risk of proximal thoracic curve decompensation, with a not low rate, after anterior selective fusion for major TL or L curve AIS. The determination of UIV relative to UEV and the skeletal maturity of the patient are the two factors closely associated with the presence of such a phenomenon.

To study the long term outcomes and complications of video-assisted thoracoscopic surgery (VATS) in correcting thoracic adolescent idiopathic scoliosis (T-AIS) with more than five-year follow-up.The T-AIS patients underwent corrective surgery by VATS between June 2002 and December 2006 and experienced more than five-year follow-up were retrospectively reviewed. Nine female patients with T-AIS were recruited with a mean age of 14.3 years (range 11 - 16 years) at operation. Radiological parameters including thoracic and lumbar curves, thoracic kyphosis (T(5)-T(12)), sagittal alignment of the thoracolumbar junction (T(10)-L(2)) and lumbar lordosis (T(12)-S(1)) were measured on the X-rays taken preoperatively, 3 months, 2 year postoperatively and at latest follow-up. Complications occurred after operation and during follow-up were retrieved. The Chinese edition SRS-22 was finished by patients at the latest follow-up. Repeated-measures analysis of variance and paired t test were used for statistical analysis.The patients were followed for a mean of 6.2 years (5 - 7.5 years) after VATS. The mean thoracic curve was corrected from 51° ± 8° preoperatively to 20° ± 8° at 3 months post-operation, and 21° ± 12° and 25° ± 13° at 2 year post-operation and latest follow-up, respectively. During the follow-up, no significant changes were observed regarding to coronal and sagittal radiological parameters (P0.05). Rod breakage occurred in 1 patient and Adding on was found in another one patient 2 year post-operation. Revision surgery was not needed for the solid fusion achieved and lack of correction loss. The mean score of SRS-22 at final follow-up was 4.3 ± 0.3, with high score in most of the domains.Loss of curve correction and implant-related complication are found in VATS-treated T-AIS patients at the long-term follow-up. Although the patients show high scores in SRS-22, which indicated higher functional outcome and satisfaction to the operation, special care should be taken for applying VATS to T-AIS patients for the concern of long-term complication.

To investigate whether the titrate-resistant acid phosphatase 5 (ACP5) gene polymorphisms were associated with the occurrence or curve severity of adolescent idiopathic scoliosis (AIS).There were 372 AIS patients from January 2006 to December 2008 and 239 normal controls from March 2005 to August 2006 were recruited. The Cobb angles were ≥ 10° in all AIS patients. Using the haplotype data of Han population from the Hapmap Project, two tag SNPs (rs2229531, rs2071484) were defined for ACP5 gene. PCR-restriction fragment length polymorphism was used for the genotyping.No polymorphism in rs2229531 was found in this study. The genotype and allele frequency distribution in rs2071484 were similar between AIS patients and normal controls (χ(2) = 3.336 and 1.438, P0.05). The mean maximum Cobb angles of different genotypes of rs2071484 in ACP5 gene were 38° ± 19° in AA, 34° ± 14° in AG and 38° ± 21° in GG, which were similar with each other among AIS patients who reached skeletal maturity or received surgery treatment (P = 0.157).The ACP5 gene is neither associated with the occurrence nor the curve severity of AIS.

To compare the results of spinal correction for severe and rigid thoracic adolescent idiopathic scoliosis (T-AIS) by combined anterior endoscopic release/posterior hybrid constructs of proximal hooks and distal pedicle screws spinal fusion (APSF) and an all-pedicle screw construct posterior-only spinal fusion (PSSF).T-AIS patients with curves ≥ 70° and flexibility ≤ 50% who underwent APSF from November 2001 to December 2008 were retrospectively reviewed (APSF group). In addition, the patients treated by PSSF with comparable curve severity and flexibility were selected as control (PSSF group). All patients had a minimum 2-year follow-up. The thoracic curve and kyphosis were measured on standing long-cassette posteroanterior and lateral radiographs of entire spine taken at pre-operation, post-operation and last follow-up. The radiographic parameters, fusion levels, implant density and complications were compared between two groups.There were 18 patients treated with APSF and 27 with PSSF, with mean age of (15.9 ± 2.1) years and (15.8 ± 2.9) years, respectively. In patients treated with APSF, the mean thoracic curve was 87° ± 12° with 58% ± 13% correction after operation; while in those treated with PSSF, the mean thoracic curve was 79° ± 8° with 59% ± 8% correction after operation. The number of levels fused was 12.7 ± 1.2 and 12.8 ± 1.4, while the implant density was 48% ± 5% and 61% ± 6% in APSF group and PSSF group, respectively. Patients treated with APSF and PSSF were followed by (4.5 ± 0.6) years and (2.8 ± 0.7) years, with a mean loss of correction of 4.4° and 1.9° at final follow-up. Despite the significant higher implant density found in PSSF (t = 6.123, P0.001), there were no statistically significant differences between the groups for gender, age, number of levels fused, preoperative coronal/sagittal Cobb measurements, coronal curve flexibility, or amount of postoperative coronal Cobb correction.In patients with severe and rigid T-AIS, PSSF could achieve same curve correction as an APSF by increasing implant density. In treating scoliosis patients with high risk of having loss of curve correction, implant complications or pseudarthrosis, APSF is recommended to achieve solid spinal fusion.

To compare the sagittal profiles between thoracic idiopathic scoliosis (IS) patients with different curve progression and to determine the risk factors associated with curve progression.A total of 83 thoracic IS patients from September 2009 to May 2010 were included in this study and were divided into 3 groups according to different curve progression. All the patients did not receive any previous treatments. There were 26 skeletally mature patients whose Risser sign were 5 degree with Cobb angle40° in non-curve progression group (NCP group), 29 mature patients whose Risser sign were 5 degree with Cobb angle ≥ 40° in moderate curve progression group (MCP group) and 28 immature patients whose Risser sign ≤ 3 degree with Cobb angle ≥ 40° in severe curve progression group (SCP group). Five sagittal parameters, including thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic incidence (PI) and pelvic tilt (PT) were measured on the lateral X-ray films. Analysis of variance was used to compare these parameters among the 3 groups.The average thoracic Cobb angle was significantly smaller in NCP group when compared with MCP group (P0.01) or SCP group (P0.01), but not significantly different between the 2 latter groups (P = 0.619). The average TK was 19° ± 7° in NCP group, 13° ± 6° in MCP group and 8° ± 5° in SCP group. The average TK was significantly smaller in SCP group when compared with MCP group (P = 0.011) or NCP group (P0.01), while the average TK was significantly smaller in MCP group when compared with NCP group (P0.01). None of the other 4 parameters showed any significant difference between the 3 groups (P0.05).Thoracic hypokyphosis is strongly associated with curve progression in thoracic IS patients. Pelvic sagittal profile may not be involved in the underlying mechanism of curve progression in thoracic IS patients.

A retrospective radiographical study of pre- and postoperative anterior chest wall shape in thoracic adolescent idiopathic scoliosis.To assess the anterior chest wall deformity and define its relationship with other deformed components in adolescent idiopathic scoliosis. The surgical influence on the deformed chest wall contour was also evaluated to improve the clinical recognition of the risk factors associated with aggravated chest wall shape postoperatively.Anterior chest wall deformity is one of the major cosmetic concerns that may be attributable to rotational coupling in adolescent idiopathic scoliosis. Patients could be quite different in their anterior chest wall appearance with similar spinal angulation. The surgical improvement of this deformed chest wall shape is also quite elusive and the reverse could also happen despite excellent correction in Cobb angle. We investigated whether or not the anterior chest wall deformity was independent in the severity from the codevelopment of spinal curvature, translation, and vertebral rotation.In this retrospective study, 110 sets of computed tomographic scans, 70 of which had both pre- and postoperative images, were retrieved and analyzed. The ImageJ software (National Institutes of Health, Bethesda, MD) was used to manipulate formatted computed tomographic scans into 3-dimensional anterior chest wall reconstructions. Multiple anterior and posterior deformity parameters were evaluated, correlated, and compared.The preoperative Cobb angle of major thoracic curve, chest wall angle (CWA), rib hump (RH), angle of the sternum relative to the apical vertebral body (α), sternum-rib ratio (S-R ratio), apical vertebral rotation (AVR), and angle of trunk rotation (ATR) averaged 54.4° ± 15.2°, 5.4° ± 3.9°, 14.7° ± 5.4°, 80.5° ± 7.8°, 1.3° ± 0.2, 12.3° ± 6.5°, and 8.8° ± 4.6°, respectively. The thoracic Cobb angle demonstrated moderate correlation with CWA, RH, α, S-R ratio, AVR, and ATR (r = 0.377, 0.604, -0.401, 0.514, 0.530, and 0.517, respectively, P0.001). The RH demonstrated moderate correlation with AVR (r = 0.546, P0.001). No statistically significant relationships between CWA and RH, AVR, and ATR were detected (r = 0.129, 0.043, -0.039, P0.05). The AVR demonstrated significant correlation with α and S-R ratio (r = -0.757, P0.001; r = 0.213, P0.05). Averaged CWA with different curve apex showed a normal distribution shape, with the highest at T9 level. The postoperative thoracic Cobb angle, S-R ratio, AVR, and ATR improved significantly (P0.05), with the exception of the postoperative CWA and α (P0.05). Postoperative |CWA| aggravated in 52.8% of the patients, with 38.6% beyond 5°, which showed a significantly lower average preoperative CWA (3.0° ± 2.8°) compared with the rest of patients with decreased CWA (7.9° ± 3.1°) (P0.001).Idiopathic scoliosis is associated with distinctive anterior chest wall deformity, with its variations partially attributable to Cobb angle and apex location, but not directly correlated with AVR. Incidence of aggravated postoperative anterior chest wall shape is notable in our study, and patients should be informed of this risk beforehand. Small preoperative CWA and apical vertebra located above T9 were associated with relatively higher risk of postoperative chest wall shape aggravation.

To investigate the effect of potential spinal growth on the posterior-only spinal instrumentation of adolescent idiopathic scoliosis (AIS).From June 2003 to October 2007, 40 patients received posterior-only spinal instrumentation. Group of open triradiate cartilage (Group A) included 16 female AIS patients with mean age of 11.8, and group of closed triradiate cartilages (Group B) covered 24 female AIS patients with mean age of 13.7. The mean preoperative Cobb angles of Group A and B were 53.3° and 49.6° respectively, and the mean kyphosis in the sagittal plane was 27.7° and 27.8° respectively.The post-operative Cobb angles were 22.2° (Group A) vs. 20.7° (Group B) (P = 0.34) with correction rate of 58.3% (Group A) vs. 57.7% (Group B) (P = 0.83). The mean Cobb angles at final follow-up were 24.8° (Group A) vs. 21.1° (Group B) (P = 0.05) with the correction loss of 5.3% (Group A) vs. 1.0% (Group B) (P = 0.01). In the sagittal plane, the average post-operative kyphosis was 22.5° (Group A) vs. 23.9° (Group B) (P = 0.49) with correction of 5.2° (Group A) vs. 3.9°(Group B) (P = 0.63). The mean kyphosis at final follow-up was 20.8°(Group A) vs. 24.7°(Group B) (P = 0.04) with the correction loss of -1.7° (Group A) vs. 0.8°(Group B) (P = 0.01). Group A showed obvious correction loss in the coronal plane and decrease of kyphosis in the sagittal plane. Adding on phenomenon was found in 2 cases with Lenke type I with selected fusion in Group A, but not in Group B.Although similar post-operative correction is found in AIS patients with OTRC or CTRC, the loss of correction and "adding on phenomenon" are more likely to happen in patients with OTRC.

The aim of this study was to investigate the association of insulin-like growth factor-1 receptor (IGF-1R) with metastasis and prognosis of osteosarcoma patients.RT-PCR and Western blot assays were performed to detect IGF-1R mRNA and protein expression in 26 osteosarcoma and noncancerous bone tissues. Immunohistochemistry was performed to analyze the correlation of IGF-1R expression in 84 osteosarcoma tissues with clinicopathological factors or survival of patients. Lentivirus-mediated RNA interference system was employed to downregulate IGF-1R expression and analyze the effects of IGF-1R downregulation on invasion and metastasis of osteosarcoma cells.The relative levels of IGF-1R mRNA and protein expression were significantly higher in osteosarcoma tissues than in corresponding noncancerous bone tissues. The expression of IGF-1R protein was closely associated with surgical stage and distant metastasis of osteosarcoma patients. Osteosarcoma patients with high IGF-1R expression had poorer survival, and multivariate Cox analyses showed that high IGF-1R expression was an independent prognostic maker. Lentivirus-mediated targeting IGF-1R could significantly inhibit adhesion, migration, invasion, and metastasis of osteosarcoma cells, which might be correlated with of inactivation of Akt signaling pathway.IGF-1R is an independent prognostic marker for osteosarcoma patients and increased expression of this molecular is correlated with metastasis of osteosarcoma.

STUDY DESIGN: To compare the preoperative and postoperative relative position of the thoracic aorta to the vertebrae in patients with idiopathic scoliosis (IS) after anterior corrective surgery without parietal pleura closure. OBJECTIVE: To investigate the impact of unrepaired parietal pleura on thoracic aorta migration after anterior correction of right thoracic IS. SUMMARY OF BACKGROUND DATA: Vascular injuries caused by vertebral screws have been reported in several studies. Recent studies showed an anteromedial shift of thoracic aorta after anterior curve correction with closure of the parietal pleura in thoracic IS. Migration of the aorta in patients with nonclosed parietal pleura has not been studied before, although it has been speculated in benefiting the transposition of the aorta and thus reduces the risk of vascular injury. METHODS: Fifteen IS patients with predominant right thoracic scoliosis who underwent anterior instrumentation without parietal pleura closure were recruited for the study. There were 10 female and 5 male patients with an average age of 15.9 years. The following parameters were measured on preoperative and postoperative computed tomographic scans: angle α: aorta-vertebral angle; distance a: distance between the aorta and the left rib head; distance b: distance from aorta to vertebral body cortex. RESULTS: From computed tomographic measurements, the angle α from T5 to T12 ranged from 28.9 to 68.3 degrees before surgery and 18.8 to 63.2 degrees after surgery. The distance a ranged from 5.6 mm to 28.1 mm before surgery and 2.3 mm to 24.3 mm after surgery. The distance b ranged from 1.7 mm to 4.3 mm before surgery and 2.3 mm to 8.0 mm after surgery. These changes in all the parameters reached statistically significant difference at all the levels except in upper and lower end vertebrae (P

To evaluate the early outcomes of children with congenital scoliosis treated by one-stage transpedicular hemi-vertebra resection.From July 2005 to June 2006, 27 consecutive cases of congenital scoliosis managed by one-stage transpedicular hemi-vertebra resection with instrumentation were investigated retrospectively. There were 11 girls and 16 boys, with a mean age of 5.5 years at surgery (range 1.3 - 10.0 years). Location of the hemi-vertebra was in the thoracic spine in 12 cases and in the lumbar spine in 15 cases. Radiographic evaluations were performed on the preoperative, postoperative, and latest follow-up standing posteroanterior and lateral radiographs.The average operation time was 4 hours (range 3-6 hours), and the mean blood loss during operation was 750 ml (range 300 - 2200 ml). The mean fusion level was 2 to 7 segments, average 4.4 segments. The average follow-up period was 16 months (range 12 - 34 months). Mean Cobb angle of the total main curve was 40.0° before surgery, 12.6° after surgery, and 15.2° at latest follow-up. Mean Cobb angle of the segmental main curve was 35.6° before surgery, 11.6° after surgery, and 12.1° at latest follow-up. The trunk shift was improved from 16.5 mm before operation to that of 7.5 mm after the operation and 7.6 mm at the latest follow-up. Compensatory cranial curve improved from 19.4° before surgery to 8.9° after surgery, and compensatory caudal curve improved from 26.3° to 12.8°. The angle of segmental kyphosis was 26.4° before surgery and 14.6° after surgery in cases with thoracic hemivertebrae, and averaged 11.2° before surgery and 3.9° after surgery in cases with lumbar hemivertebrae. Peri-operative complications included two pedicle screws malpositioning and one case with pelvic tilt. There was no neurological complication.One-stage transpedicular hemi-vertebra resection with instrumentation has a good capability of correcting deformity on the frontal and sagittal planes, which is available in children with middle or lower thoracic or lumbar hemivertebrae.

To investigate the impairment pattern and the influencing factors of pulmonary function in patients with Marfan and Marfanoid syndrome associated scoliosis (MS).In this retrospective study, totally 25 MS patients (aged 11 - 20 years, 11 boys and 14 girls) who received posterior instrumentation and fusion (Group A) and 38 adolescent idiopathic scoliosis (AIS) patients (Group B) (aged 10 - 19 years, 11 boys and 27 girls) were included from February 1998 to September 2007. The curve pattern was matched in both groups. The preoperative pulmonary function test (PFTs) were compared in two groups. And the parameters influencing the preoperative pulmonary function were analyzed in group A.In Group A, the Cobb angle of thoracic curve was negatively correlated with the percentage of predicted pulmonary volumes (VC%, FVC% and FEV1%) (r = -0.514, -0.503, -0.464, P0.05). And the reduction of lung function parameters (VC%, FVC%, FEV1% and MMEF%) was more severe in Group A than in Group B with compared magnitude of thoracic curve (P0.05). In Group A, the extent of impairment of pulmonary function in patients with the number of vertebrae involved ≥ 8 were more severe than those involved8 vertebrae (P0.05). However, there was no significant difference of deterioration of lung function between the higher apex (T₄₋₈) subgroup and lower apex (T₉₋₁₂) subgroup. And no correlation was found between thoracic kyphosis and the degrees of impairment of respiration function.Patients with MS have mixed ventilation dysfunction, which is more severe than AIS patients with matched age and Cobb angle. The pulmonary dysfunction in MS patients can be influenced by the severity of thoracic curve and the number of involved vertebrae.

To evaluate the efficacy of preoperative Halo-femoral traction in the treatment of rigid idiopathic scoliosis.Sixteen patients with rigid idiopathic scoliosis treated with Halo-femoral traction before posterior spine fusion from July 2003 through May 2006 were studied retrospectively. There were 4 male and 12 female, with a mean age of 16 years (range, 12-20 years). The coronal Cobb angles of coronal major curve and the thoracic kyphosis (T(5)-T(12)) were 111 degrees and 64 degrees, respectively. All the patients underwent preoperative Halo-femoral traction. After the maximum weight traction for 2-3 weeks, a posterior instrumentation and fusion was performed. The correction rate of coronal major curve on preoperative side bending film, on supine film after Halo-femoral traction and after surgery was compared.The maximum traction weight averaged 19 kg. All patients had an at least 12-month follow-up. One patient experienced transient brachial plexus palsy and complete recovery was achieved after reducing the traction weight. No neurologic complication, death and respiratory failure occurred after surgery. In comparison to the correction rate of 18.7% on preoperative side bending film, the correction rate of coronal major curve after Halo-femoral traction increased by 13.2% (P0.05). The postoperative correction rate of coronal major curve and thoracic kyphosis was 48.6% and 51.9%, respectively. At the final follow-up, the coronal and sagittal correction loss averaged 2.0% and 5.8%, respectively.Preoperative Halo-femoral traction combined with intraoperative posterior spinal release can significantly enhance the correction rate for rigid idiopathic scoliosis. However, the traction complications should be worthy of vigilance.

To investigate the pulmonary dysfunction patterns in patients of scoliosis associated with neurofibromatosis type I (NF1) and to identify factors affecting the pulmonary function in patients with scoliosis associated with NF1.Preoperative pulmonary function tests (PFTs) were evaluated in 100 patients with scoliosis [NF1 group, 36 cases; idiopathic scoliosis (IS) group, 64 cases] from January 2003 to June 2009. According to location of apical vertebra and dystrophic change in patients with NF1, the parameters of pulmonary function [vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMEF), maximal voluntary ventilation (MVV)] were compared between NF1 group and IS group, and between the subgroups of NF1. The correlation between pulmonary function parameters and radiographic parameters of scoliosis was analyzed.The VC, FVC, FEV1, MMEF, MVV in NF1 group and IS group were of no significant difference (P0.05). In NF1 patients, the pulmonary dysfunction was more severe in thoracic subgroup than non-thoracic subgroup (P0.05), while there was no difference between dystrophic scoliosis and non-dystrophic scoliosis (P0.05). The location of apical vertebra and the severity of scoliosis correlated significantly with the pulmonary dysfunction in NF1 group.The pattern of pulmonary dysfunction in scoliosis associated with NF1 is similar with IS. Pulmonary dysfunction is more severe in thoracic scoliosis. The location of apical vertebra and the severity of scoliosis are the risk factors influencing the pulmonary dysfunction.

The development of scoliosis in animal models with induced asymmetric rib growth suggested the possible role of asymmetric rib growth in the etiopathogenesis of adolescent idiopathic scoliosis (AIS). Asymmetric rib length is well recognized in idiopathic scoliosis, however, whether this rib asymmetry was primary or secondary has not been clearly documented. We measured the lengths of all ribs in 48 patients with AIS and 29 patients with scoliosis associated with syringomyelia and Chiari I malformation (SS). In both groups, ribs on the concave side were significantly longer than those on the convex side in apical area. The rib length difference was significantly associated with magnitude of the Cobb angle of thoracic curve. However, the rib length discrepancy showed no difference between AIS and SS group. The finding of similar asymmetry of rib length in both AIS and SS patients with thoracic curve indicated the discrepancy found in AIS might be secondary to the spinal deformity rather than its etiological factor.

To analyze the influence of thoracic kyphosis on the sagittal compensatory mode of the spine in idiopathic thoracic scoliosis after the selective thoracic fusion.Ninety AIS patients (mean age 14.5 years old) who received selective thoracic fusion from February 1999 to December 2005 in one institution with at least 24-month follow-up were evaluated. Forty-one patients underwent anterior spinal fusion and forty-nine patients underwent posterior spinal fusion. And then the patients were divided into two subgroups according to the magnitude of preoperative thoracic kyphosis (TK): Group A, TK less than 10 degrees ; and Group B, TK more than 10 degrees . The radiological parameters were measured including: thoracic and lumbar curve magnitude, TK, lumbar lordosis (LL), thoracolumbar junction kyphosis (T(10)-L(2), TJK), distal junctional kyphosis (DJK), sagittal vertical axis (SVA).At final follow-up, TK, TJK and DJK increased significantly compared with preoperative Cobb angle in subgroup A patients who underwent anterior spinal fusion (P0.05). Generally, there was a lordosis loss of TJK and DJK during follow-up. While in subgroup B, TJK at final follow-up increased apparently compared with preoperative Cobb angle (P0.05). And there was a increased trend of DJK in spite of no significant difference, however, there was no obvious change of TK in subgroup B. At the final follow-up, TK and TJK increased significantly in subgroup A patients who underwent posterior spinal fusion (P0.05). And there was a increased tendency of DJK during follow-up, although there was no significant difference. And there was no obvious change of TK, TJK and DJK in subgroup B. There was a increased trend of LL in spite of no significant difference in group A patients who underwent anterior or posterior spinal fusion. The sagittal balance maintained well during follow-up in both groups.For AIS patients with thoracic hypokyphosis, normal TK and LL could be achieved during follow-up with selective thoracic instrumentation. However, the increase of DJK and TJK may occur during the follow-up, and the risk factors may be the anterior short segmental fusion and the reconstruction of the sagittal profile in the hypokyphosis patients.

To evaluate and analyze the misplacement patterns of the pedicle screws in surgical correction of patients with adolescent idiopathic scoliosis.For this study, 70 consecutive cases of patients with adolescent idiopathic scoliosis treated by posterior instrumented spinal fusion with pedicle screws were investigated from July 2008 to September 2008. Postoperative CT scans were performed in all cases. The patients included 58 girls and 12 boys, with a mean age of 14.5 +/- 2.7 years at surgery (range 12 - 19 years). Pedicle screws were inserted using anatomic landmark with free hand technique. A number of parameters were measured using PacsClient software (PACS) on workstation, which included distances of the penetration of medial, lateral pedicle cortex and anterior vertebral cortex. The distance between edge of aorta and tip of screw should be measured if left pedicle screw penetrated lateral pedicle cortex or anterior vertebral cortex. Misplacement screws with2 mm of either pedicular cortex perforation and grievous screws with4 mm of medial pedicle perforation or contour of aorta were defined. The influencing factors for misplacement screws were analyzed.A total of 1030 pedicle screws were inserted, 773 in thoracic pedicle and 257 in lumbar pedicle. There were 108 (10.5%) misplacement screws, 35 of which penetrated lateral pedicle cortex, 56 of which penetrated medial pedicle cortex, 33 of which penetrated vertebral anterior cortex. Misplacement screw rate of apical vertebra, 5 segments above apical vertebra (AV-5s) and 4 segments below apical vertebra (AV + 4s) were higher than other levels. Most of grievous screws were placed in apical vertebra region.The risk factors for misplacement screws included Cobb angle90 degrees and vertebrae rotation extent up to III-IV. Care should be exercised during pedicle screw instrumentation in the apical region of the main thoracic curve, AV-5s region and AV + 4s region.

To investigate the association of matrilin-1 gene polymorphisms with adolescent idiopathic scoliosis (AIS) risk.This study population consisted of 419 patients with AIS and 460 healthy controls. The maximum Cobb angle of AIS patients was recorded. For initial screening, the 7 tagSNPs were genotyped in 197 cases and 172 controls. Next, we validated any significant associations in additional sample of 222 cases and 288 controls. Single-marker and haplotype analysis were employed. Genotyping was performed by PCR-RFLP method.We found that allele G of rs1149048 was a significant predisposition allele of AIS (P = 0.0027, OR = 1.34 within 95% CI = 1.11 approximately 1.62), and individuals with genotype GG had a higher risk for AIS compared to AA + AG (P = 0.0008, OR = 1.61 within 95% CI = 1.22 approximately 2.12). Polymorphism of rs1149048 was also associated with curve severity in AIS patients. And a significantly higher in maximum Cobb angle was found in patients with GG genotype (P = 0.002).It is concluded that the tagSNP rs1149048 polymorphism in the MATN1 promoter region is associated with both susceptibility and disease severity in AIS.

Study design A correlation analysis between histologic grade (HG) of iliac crest apophysis and skeletal age assessments. Objective To study the correlation between HGs of iliac crest apophysis and the skeletal age of hand and wrist, digital skeletal age (DSA), and Risser sign in the girls with adolescent idiopathic scoliosis (AIS). Summary of background data The evaluation of the remaining growth of the patients clinically and radiologically is highly significant in predicting the curve progression and thus influencing the treatment strategy in AIS. Methods Fifty-three AIS girls with a mean age of 14.0 years undergoing corrective posterior spinal surgery and instrumentation with autogenous bone graft were recruited. Menarche status was recorded while the skeletal age of hand and wrist, DSA, and Risser grade were evaluated radiologically. Using a standardized HG of proliferative chondrocyte zone of the iliac crest apophysis, correlation between the HGs and the radiologic and clinical skeletal maturity parameters was analyzed. Results The HGs were negatively correlated with the radiologic parameters with the highest correlation coefficient between HGs and skeletal age of hand and wrist. The negative correlation between HGs and the 2 clinical parameters was significant and could be enhanced by combining with the radiologic parameters. No proliferative chondrocyte zone of the apophysis was detected when patients were either over 16 years of skeletal age or Risser grade 5, as well as 2-year postmenarche or over 15 years of chronological age in patients with DSA stage III and Risser grade 4. Conclusion Radiologic skeletal age of the wrist and digits can provide important information for maturity assessment in girls with AIS. It can also enhance the sensitivity of clinical parameters in determining the remaining growth potential.