Occult Andersson lesions in patients with ankylosing spondylitis: undetectable destructive lesions on plain radiographs / 中华医学杂志(英文版)

BACKGROUND@#Andersson lesions (ALs) are not uncommon in ankylosing spondylitis (AS). Plain radiography (PR) is widely used for the diagnosis of ALs. However, in our practice, there were some ALs in AS patients that could not be detected on plain radiographs. This study aimed to propose the concept of occult ALs and evaluate the prevalence and radiographic characteristics of the occult ALs in AS patients.@*METHODS@#A total of 496 consecutive AS patients were admitted in the Affiliated Drum Tower Hospital, Medical School of Nanjing University between April 2003 and November 2019 and they were retrospectively reviewed. The AS patients with ALs who met the following criteria were included for the investigation of occult ALs: (1) with pre-operative plain radiographs of the whole-spine and (2) availability of pre-operative computed tomography (CT) and/or magnetic resonance imaging (MRI) of the whole-spine. The occult ALs were defined as the ALs which were undetectable on plain radiographs but could be detected by CT and/or MRI. The extensive ALs involved the whole discovertebral junction or manifested as destructive lesions throughout the vertebral body. Independent-samples t test was used to compare the age between the patients with only occult ALs and those with only detectable ALs. Chi-square or Fisher exact test was applied to compare the types, distribution, and radiographic characteristics between detectable and occult ALs as appropriate.@*RESULTS@#Ninety-two AS patients with a mean age of 44.4 ± 10.1 years were included for the investigation of occult ALs. Twenty-three patients had occult ALs and the incidence was 25% (23/92). Fifteen extensive ALs were occult, and the proportion of extensive ALs was significantly higher in detectable ALs (97% vs. 44%, χ2 = 43.66, P < 0.001). As assessed by PR, the proportions of osteolytic destruction with reactive sclerosis (0 vs. 100%, χ2 = 111.00, P < 0.001), angular kyphosis of the affected discovertebral units or vertebral body (0 vs. 22%, χ2 = 8.86, P = 0.003), formation of an osseous bridge at the intervertebral space adjacent to ALs caused by the ossification of the anterior longitudinal ligament (38% vs. 86%, χ2 = 25.91, P < 0.001), and an abnormal height of the affected intervertebral space were all significantly lower in occult ALs (9% vs. 84%, χ2 = 60.41, P < 0.001).@*CONCLUSIONS@#Occult ALs presented with more subtle radiographic changes. Occult ALs should not be neglected, especially in the case of extensive occult ALs, because the stability of the spine might be severely impaired by these lesions.

Comparison of sagittal plane morphology of spine and pelvis in adolescents with L₅S₁ developmental spondylolisthesis and isthmic spondylolisthesis / 中国骨伤

OBJECTIVE@#To compare the sagittal morphological features of the spine and pelvis between L₅S₁ dysplastic spondylolisthesis and isthmus spondylolisthesis in adolescent.@*METHODS@#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. 0.05).@*CONCLUSIONS@#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.

Anatomical feature of lumbar and S₁ pedicle in patients with thoracolumbar kyphosis secondary to ankylosing spondylitis / 中国骨伤

<p><b>OBJECTIVE</b>To measure the correlative parameters of vertebral pedicles from L₁ to S₁ by CT scan in the patients with thoracolumbar kyphosis secondary to ankylosing spondylitis(AS) and disc degenerative disease(DDD), and analyze their anatomical difference in order to provide the selection and placement of pedicle screw during operation.</p><p><b>METHODS</b>The clinical data of 30 male AS patients (AS group) with the mean age of(35.7±9.5) years (ranged, 23 to 51) and 30 male DDD patients (DDD group) with the mean age of(52.4±8.9) years(ranged, 39 to 64) underwent surgery in our institution from March 2012 to November 2014 were analyzed. The CT scans of lumbar and sacrum were performed before surgery. The parameters of vertebral pedicle from L₁ to S₁ were measured and compared, including pedicle width (PW), pedicle screw path length (PL), pedicle height (PH), pedicle transverse angle (EA), and pedicle inclined angle (FA). Paired sample t-test was used to detect the divergence in the above-mentioned data between left and right sides. In addition, results between two groups were compared using independent sample t-test.</p><p><b>RESULTS</b>The study showed that a gradual increase in the average pedicle width both AS group and DDD group from L₁ to S₁. The average PW of AS group was bigger than DDD group in L₅ and S₁(<0.05), it was(16.47±2.66) mm and (21.76±2.97)mm vs. (14.51±2.11)mm and (18.87±2.14) mm respectively;the average PL of DDD group was smaller than AS group from L₁ to S₁(<0.05); the both maximum of PL were in L₃ segment; the average EA of AS group was smaller than DDD group from L₁ to S₁; the average FA of AS group was significantly smaller than DDD group from L₃ to S₁, (<0.05), was(-2.88±10.24)°, (-7.88±10.22)°, (-7.70±10.40)°, (-5.15±10.25)° vs. (4.05±2.21)°, (7.79±4.38)°, (7.07±3.21)°, (12.62±3.21)°, respectively.</p><p><b>CONCLUSIONS</b>Increasing the strength of internal fixation is feasible to insert the larger and bigger pedicle screws in low lumbar and S₁ among AS patients, while the EA should be decreased properly and the direction on the sagittal plane should be adjusted.</p>

The correlation between T1 tilt and cosmetic shoulder balance in Lenke type 2 adolescent idiopathic scoliosis patients / 中华外科杂志

<p><b>OBJECTIVE</b>To study the relationship between T1 tilt and cosmetic shoulder balance in adolescent idiopathic scoliosis (AIS) patients.</p><p><b>METHODS</b>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. CSH > 5 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 tilt > 5° 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.</p><p><b>RESULTS</b>T1 tilt was found to be significantly correlated with CSHi and CSHo (r = 0.25 and 0.28, P < 0.05).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.</p><p><b>CONCLUSIONS</b>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.</p>

Correlation between the shifting of medulla oblongata and cerebellum and syrinx resolution after posterior fossa decompression in Chiari malformation / 中华外科杂志

<p><b>OBJECTIVES</b>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).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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) .</p><p><b>CONCLUSION</b>The upward shifting of the bulbopontine sulcus and the lower extreme of cerebella tonsil might be implicated in the mechanisms of postoperative syrinx resolution.</p>

The effect of sympathectomy on the development and progression of scoliosis in bipedal mice model / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of sympathectomy on the development and progression of scoliosis in bipedal C57BL/6J mice model.</p><p><b>METHODS</b>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 of > 10°. Incidence of scoliosis and severity of curves were compared among groups using Chi-square test and One-way analysis of variance, respectively.</p><p><b>RESULTS</b>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, P < 0.001), but there was no significant difference in mean Cobb angle between Group 2 and 3.</p><p><b>CONCLUSIONS</b>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.</p>

Risk factors of thoracic curve decompensation after anterior selective fusion in adolescent idiopathic scoliosis with major thoracolumbar or lumbar curve / 中华外科杂志

<p><b>OBJECTIVES</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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 (P < 0.05).</p><p><b>CONCLUSIONS</b>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.</p>

Idiopathic thoracolumbar/lumbar scoliosis treated with anterior correction and interbody fusion with calcium phosphate cement / 中华外科杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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).</p><p><b>CONCLUSION</b>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.</p>

Early outcome of vertical expandable prosthetic titanium rib technique in treating early-onset scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the early outcome of vertical expandable prosthetic titanium rib (VEPTR) technique in treating early-onset scoliosis.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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, P < 0.05), 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, P < 0.001), and average T(1)-S(1) height from (24.4 ± 3.8) cm to (32.5 ± 5.3) cm (t = 9.080, P < 0.001). 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.</p><p><b>CONCLUSIONS</b>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.</p>

Association between tartrate-resistant acid phosphatase 5 gene polymorphism and adolescent idiopathic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>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).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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, P > 0.05). 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).</p><p><b>CONCLUSION</b>The ACP5 gene is neither associated with the occurrence nor the curve severity of AIS.</p>

Long term outcome of video-assisted thoracoscopic surgery for thoracic adolescent idiopathic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>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.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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 (P > 0.05). 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.</p><p><b>CONCLUSIONS</b>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.</p>

A comparative study on the surgical outcomes of spinal fusion in adolescent idiopathic scoliosis patients with or without triradiate cartilages closed / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the effect of potential spinal growth on the posterior-only spinal instrumentation of adolescent idiopathic scoliosis (AIS).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSIONS</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.</p>

Comparison of the sagittal profiles between thoracic idiopathic scoliosis patients with different curve progression / 中华外科杂志

<p><b>OBJECTIVES</b>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.</p><p><b>METHODS</b>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 angle < 40° 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.</p><p><b>RESULTS</b>The average thoracic Cobb angle was significantly smaller in NCP group when compared with MCP group (P < 0.01) or SCP group (P < 0.01), 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 (P < 0.01), while the average TK was significantly smaller in MCP group when compared with NCP group (P < 0.01). None of the other 4 parameters showed any significant difference between the 3 groups (P > 0.05).</p><p><b>CONCLUSIONS</b>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.</p>

Association between tissue inhibitor of metalloproteinase-2 gene polymorphism and adolescent idiopathic thoracic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the association between the tissue inhibitor of metalloproteinase-2 (TIMP-2) gene polymorphisms with the predisposition and disease severity of thoracic adolescent idiopathic scoliosis (AIS).</p><p><b>METHODS</b>Three hundred and fifty-four female thoracic AIS patients treated from January 2007 to March 2009 and 210 healthy female who underwent health examination during March 2005 to June 2006 as normal controls were recruited in this study. One SNP-418G/C (rs8179090) in the promoter region were selected for TIMP-2 gene. PCR- RFLP was used for genotyping.</p><p><b>RESULTS</b>No significant differences of genotype and allele frequency distribution were found between AIS patients and normal controls (P > 0.05). In AIS patients, the frequency of C allele of the patients with the body mass index (BMI) < 17 kg/m(2) was significantly higher than those with the BMI > or = 17 kg/m(2) (P < 0.05), and the frequency of C allele of cases with the major Cobb angle > or = 40 degrees was significantly higher than that with Cobb angle < 40 degrees (P < 0.05). Among the patients who reached skeletal maturity without any interference of natural history, significantly higher average maximum Cobb angle was found in patients with GC and CC genotype compare with those with GG genotype.</p><p><b>CONCLUSIONS</b>The SNP-418G/C (rs8179090) in the promoter region of TIMP-2 gene may be associated with abnormal growth pattern and curve progression of thoracic AIS. TIMP-2 gene is a disease-modifier gene of thoracic AIS.</p>

Pulmonary dysfunction patterns in patients with Marfan and Marfanoid syndrome associated with scoliosis and the influencing factors / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the impairment pattern and the influencing factors of pulmonary function in patients with Marfan and Marfanoid syndrome associated scoliosis (MS).</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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, P < 0.05). 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 (P < 0.05). In Group A, the extent of impairment of pulmonary function in patients with the number of vertebrae involved ≥ 8 were more severe than those involved < 8 vertebrae (P < 0.05). 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.</p><p><b>CONCLUSIONS</b>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.</p>

Efficacy of preoperative Halo-femoral traction in the treatment of rigid idiopathic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the efficacy of preoperative Halo-femoral traction in the treatment of rigid idiopathic scoliosis.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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% (P < 0.05). 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.</p><p><b>CONCLUSIONS</b>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.</p>

Early outcome of one-stage posterior transpedicular hemi-vertebra resection in the treatment of children with congenital scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the early outcomes of children with congenital scoliosis treated by one-stage transpedicular hemi-vertebra resection.</p><p><b>METHODS</b>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.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSION</b>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.</p>

Characteristic of somatosensory evoked potentials in adolescent idiopathic scoliosis and relationship with Cobb angle / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the abnormality of somatosensory evoked potentials (SEPs) in adolescent idiopathic scoliosis (AIS) with different curve magnitudes, and to explore its effect on the etiopathogenesis of AIS.</p><p><b>METHODS</b>Posterior tibial nerve SEPs were evaluated on 489 young operative treated AIS patients with a Cobb angle >40 degrees and 45 age-matched healthy control individuals. Absence of SEPs waveforms, prolongation of peek latency or asymmetrical peek latency were defined as pathological change. Base on the control reference, the incidence of pathological SEPs was determined in AIS group. The association of abnormal SEPs and curve severity for AIS patients was also assessed.</p><p><b>RESULTS</b>Peek latency corrected for body height was slightly longer in AIS patients than in controls, however, with no significant difference. Inter side difference of latency was significantly larger in AIS patients. Abnormal SEPs were found in 166 of 489 AIS patients. Among these, 17 (10.2%) showed absent waveforms, 50 (30.1%) had unilateral latency prolongation, 38 (22.9%) had bilateral latency prolongation, and 120 (72.3%) showed significant inter side difference. Statistical analysis failed to show a correlation between abnormal SEPs and the curve severity of spinal deformity.</p><p><b>CONCLUSION</b>Disorder of somatosensory pathways does exist in a subgroup of AIS patients, and it might be a primary factor other than secondary change, and could play an import role in the etiopathogenesis of AIS.</p>

Radiologic analysis of factors predicting the surgical reduction of lumbar spondylolisthesis / 中华外科杂志

<p><b>OBJECTIVES</b>To find out the radiologic factors predicting the outcomes of reduction of lumbar spondylolisthesis.</p><p><b>METHODS</b>Forty two patients were treated with pedicle screw fixation with posterolateral fusion because of lumbar spondylolisthesis, with the average age of 56.0 years. There were 11 males and 31 females; 20 degenerative spondylolisthesis cases, and 22 isthmic spondylolisthesis cases; 1 L(3,4) case, 26 L(4,5) cases and 25 L(5)S(1) cases; 23 grade I patients and 19 grade II ones. All patients were taken the X-ray examination before operation and one week after operation. Measurements of slip ratio, percentage disc height, slip angle, lumbar lordosis angle and sacral slope angle were based on pre-operation X-rays. Measurements of the post-operation slip ratio were based on post-operation X-rays. Multivariate regression analysis was used to analysis the correlation between reduction ratio and pre-operation slip ratio, slip angle, percentage of disc height, lumbar lordosis angle and sacral slope angle.</p><p><b>RESULTS</b>The average pre-operation slip ratio was (22.5 +/- 10.6)%. The pre-operation percentage disc height was 0.23 +/- 0.10, the slip angle was 4.4 degrees +/- 5.4 degrees , the lumbar lordosis angle was 43 degrees +/- 13 degrees and the sacral slope angle was 34 degrees +/- 10 degrees . The reduction ratio was (63.2 +/- 27.9)%. No correlation was found among reduction ratio with pre-operation slip ratio, slip angle and sacral slope angle, but a positive correlation between reduction ratio and the pre-operation percentage of disc height (P < 0.05), a positive correlation between reduction ratio and the pre-operation lumbar lordosis angle (P < 0.05) was found.</p><p><b>CONCLUSION</b>The percentage disc height and the lumbar lordosis angle can predict the outcomes of reduction of lumbar spondylolisthesis.</p>

Misplacement patterns of the pedicle screws in surgical correction of patients with adolescent idiopathic scoliosis / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate and analyze the misplacement patterns of the pedicle screws in surgical correction of patients with adolescent idiopathic scoliosis.</p><p><b>METHODS</b>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 with > 2 mm of either pedicular cortex perforation and grievous screws with >4 mm of medial pedicle perforation or contour of aorta were defined. The influencing factors for misplacement screws were analyzed.</p><p><b>RESULTS</b>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.</p><p><b>CONCLUSIONS</b>The risk factors for misplacement screws included Cobb angle > 90 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.</p>