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>

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 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>

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>

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>

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>

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>

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>