Rigid spinal kyphosis deformity is typically characterized by a large kyphotic Cobb angle (≥70°) and a significant decrease of intervertebral flexibility (bending flexibility<30°), due to primary spinal disease, spinal trauma or other diseases. Severe kyphotic deformity leads to a poor posture and spinal cord or neurological impairment. Three-column osteotomy, including pedicle subtraction osteotomy (PSO) and its modified methods, is the only effective treatment for such patients. For example, asymmetrical PSO (APSO) could not only achieve successful realignment of spinal biplanar balance, but also realize complete closure of osteotomy gap, which is conducive to realize solid bony fusion and provide better stability. In partial pedicle subtraction osteotomy (PPSO), the remaining cortical shell of pedicle could decrease the risk of neural injury without significant loss of correction amount, so PPSO could be a viable surgical option for spinal deformity. Besides, modified partial pedicle subtraction osteotomy (MPPSO) is commonly used for post-traumatic thoracolumbar kyphosis with an injured disc. The potential superiorities of MPPSO are that it not only increases regional stability by reserving the integrity of the lower facet joint, but also promotes direct interbody fusion in the upper disc space. For closing-opening wedge osteotomy (COWO), it could obtain more kyphotic corrections by closing posterior column and opening anterior column simultaneously. Modified closing-opening wedge osteotomy (MCOWO) is an ideal option in treating cases of thoracolumbar posttraumatic kyphosis with flat discs or wedge-shape vertebra, because great correction results were observed at follow-up with postero-superior triangular corner primarily resected. Although technically difficult and demanding, bone-disc-bone osteotomy (BDBO) is still a good option for achieving "bone-to-bone" closure of the osteotomy site to yield higher fusion rates and decrease the risk of pseudoarthrosis. A full understanding of the osteotomy range, correction effects and advantages for each type of modified PSO is essential for preoperative plans, optimal spinal sagittal reconstructions and excellent prognosis.

Sagittal translation(ST) was defined as any measurable sagittal displacement more than 5 mm between the posterior inferior edge of the cranial vertebral body and the posterior superior edge of the caudal body at the osteotomized vertebrae(OV). Ankylosing spondylitis (AS) is a chronic inflammatory disease characterized by enthesitis and heterotopic ossification affecting sacroiliac joints and vertebral column. In the late stage, the poor quality of life caused by inability to lie supine or look straight ahead were the chief reasons for spinal osteotomy. Intraoperative ST secondary to AS thoracolumbar kyphosis contributed to improvement of sagittal vertical axis (SVA) partly. However, severe ST leaded to a huge bony step in front of dura, which was prone to vascular injury, neurologic deficit and cerebrospinal fluid leakage, thus affecting surgical outcomes. Prior research indicated there were significant correlations between intraoperative ST and inappropriate maneuver, the degree of ankylosis, the kyphosis curve pattern and correction, early fracture of the anterior cortex of the OV, excessive or insufficient decancellation of the OV, mismatch between the center of correcting forces and the center of rotation, incorrect application of cantilever technique. The use of anti-ST appliances, intraoperative fluoroscopy and nerve monitoring could prevent the occurrence of ST effectively. For AS patients with ST, relevant measures or decompressive laminectomies could be taken on the basis of neurological function to prevent neurologic deficit. Due to the strong osteogenic ability in AS patients, favorable bony reconstruction and fusion could be available during follow-up after adopting corresponding treatment involving ST. A thorough understanding of mechanism and risk factors of sagittal translation was essentially instructional to spinal surgeons thereby the incidence of intraoperative ST and complications could be decreased.

With the popularization of minimally invasive concept in the treatment of lumbar degenerative disease,minimally invasive lumbar interbody fusion has gradually developed into the mainstream technique of lumbar fixation and fusion.At present,there are many types of minimally invasive lumbar interbody fusion. In this paper, four kinds of minimally invasive lumbar interbody fusion (anterior lumbar interbody fusion,minimally invasive transforaminal lumbar interbody fusion,extreme lateral interbody fusion,oblique lumbar interbody fusion),which are widely used in clinical practice,are systematically described from the aspects of indication selection,technical characteristics, clinical efficacy and prevention of complications.In order to obtain the best treatment effect with the least trauma,it is necessary for the surgeons to formulate detailed surgical strategies on the basis of strictly grasping the indications,and choose the operation according to their own clinical experience and skills,so as to maximize the advantages of different minimally invasive lumbar interbody fusion.

With the popularization of minimally invasive concept in the treatment of lumbar degenerative disease,minimally invasive lumbar interbody fusion has gradually developed into the mainstream technique of lumbar fixation and fusion.At present,there are many types of minimally invasive lumbar interbody fusion. In this paper, four kinds of minimally invasive lumbar interbody fusion (anterior lumbar interbody fusion,minimally invasive transforaminal lumbar interbody fusion,extreme lateral interbody fusion,oblique lumbar interbody fusion),which are widely used in clinical practice,are systematically described from the aspects of indication selection,technical characteristics, clinical efficacy and prevention of complications.In order to obtain the best treatment effect with the least trauma,it is necessary for the surgeons to formulate detailed surgical strategies on the basis of strictly grasping the indications,and choose the operation according to their own clinical experience and skills,so as to maximize the advantages of different minimally invasive lumbar interbody fusion.

Objective:To evaluate long-term results of growth friendly non-fusion technique (GF) in the treatment of early-onset scoliosis (EOS).Methods:From August 2008 to October 2019, a total of 26 EOS patients (mean age 7.2±2.4 years old) who had completed surgery with GF treatment, including 12 males and 14 females, were reviewed retrospectively. Among them, 16 patients underwent growing rod treatment while 10 patients underwent vertical expandable prosthetic titanium rib (VEPTR) treatment. All patients had minimum 2 lengthening procedure during distraction period and over 2-year follow-up after graduation. Radiographic data were collected before and after index surgery as well as at graduation and the latest follow-up. Complications were also recorded during distraction period and after graduation.Results:A total of 145 lengthening procedures were performed in 26 patients, averagely 5.6 procedures per patient. The mean age at graduation was 12.6±1.6 years old. The average follow-up was 4.7±1.4 years duringdistraction period, and 2.9±0.9 years after graduation.The main Cobb angle was significantly decreased from 81.2°±17.3° to 41.1°±13.1°( t=8.124, P<0.001)after the index surgery, but slightly increased to 48.8°±15.4° at the end of distraction. After definitive spinal fusion, the main Cobb angle was notably decreased from 52.8°±16.1° to 45.4°±14.8° in 16 patients( t=2.415, P=0.035), with an average correction rate of 14.1%±9.4%. At the latest follow-up, the main Cobb angle was 45.2°±15.6° and the average correction rate was 44.3%±15.5% when comparing with the value before the index surgery. The thoracic and spinal height were significantly increased after initial surgery. During distraction period, the average gain of thoracic and spinal height was 3.3±0.9 cm and 5.6±1.9 cm, with the growth rate of 0.6±0.3 cm and 1.0±0.4 cm per distraction, respectively. A total of 36complications were recorded in 14 patients. There were 27 complications occurred during distraction period and 9 after graduation. Conclusion:Surgical management of EOS with growing rod and VEPTR could effectively correct the spinal deformity and maintain spinal growth. The complication rate after graduation was relative lower than distraction period. However, the correction of definitive spinal fusion during graduation was relative lower.

Objective:To investigate the outcome of posterior correction surgery for severe kyphoscoliosis secondary to spinal Gorham disease, further to explore the countermeasure in such complicated condition.Methods:From January 2005 to December 2019, a total of 12 consecutive patients were diagnosed with spinal Gorham disease. Four patients who had undergone correction surgery were reviewed retrospectively. There were 3 males and 1 female. The median age of surgery was 14.5 years (11.5 years, 27.5 years), with the median of Cobb angle of scoliosis and kyphosis 29° (21.5°, 78.0°) and 94° (78.0°, 103.0°), respectively. After Halo-gravity traction, one-stage posterior correction surgeryand Schwab grade I or II osteotomy, with pedicle screw fixation bridging the diseased vertebrae was performed. Drug therapy of bisphosphonate was recommended after surgery. The Cobb angle of scoliosis and kyphosis, coronal and sagittal balance were measured on the standing upright radiographs of the spine. CT and MRI were used to give precise evaluation of spinal and peripheral soft tissue involvement.Results:After Halo-gravity traction of 3 months (2.5 months, 3.5 months), the median of Cobb angle of scoliosis decreased to 23.5° (15.5°, 77.0°) and kyphosis decreased to 65° (57°, 83.5°) respectively. Two patients underwent facetectomyand 2 received Ponte osteotomy. The median operative time and blood loss were 5.5 h (5.1 h, 5.9 h) and 3 095ml (2 950 ml, 3 320 ml), with the fusion segment of 13.5 (12.5, 14.5) and the fixation density of 47.8% (40.9%, 57.3%). After surgery, the median of Cobb angle of scoliosis and kyphosis decreased to 18° (10.5°, 38.5°) and 59° (42.0°, 78.0°). Compared to the values before traction, the median of correction rates of scoliosis and kyphosis after surgery were 46.7% (33.1%, 59.5%) and 35% (12.3%, 51.1%) respectively. Moreover, the median of coronal balance decreased from 15.5 mm (9.0 mm, 21.0 mm) to 6.5 mm (4.0 mm, 9.0 mm), while the median of sagittal balance decreased from 14 mm (-18.0 mm, 27.5 mm) to 5.5 mm (-5.5 mm, 12.5 mm). During a median of follow-up of 2.8 years (2.0 years, 3.5 years), no complication was detected except one patient whounderwent revision surgery for rod broken.Conclusion:One-stage posterior correction surgery combined with preoperative halo-gravity tractionand postoperative anti-osteoporosis therapydemonstratedto be safe and effective for severe kyphoscoliosis secondary to spinal Gorham disease. More attention should be paid to the failure of internal fixation after surgery.

Objective: To compare the surgical outcomes between hybrid and traditional growing rod (GR) techniques in the treatment of early-onset congenital scoliosis (C-EOS). Methods: A review was conducted of C-EOS patients who had undergone hybrid GR treatment at Department of Spine Surgery, the Affiliated Drum Tower Hospital of Nanjing University Medical School. Another group of patients who had undergone traditional GR were well matched to the hybrid GR group at a 1∶1 ratio in terms of main Cobb angle, age at initial surgery, and lengthening numbers. There were 5 boys and 8 girls with an age of (5.6±2.8) years in the hybrid GR group, and 6 boys and 8 girls with an age of (6.1±3.0) years in the traditional GR group, respectively. All patients had minimum 2-year follow-up and over 2 lengthening procedures. Radiographic data were compared with paired t tests in either group between each visit, and with independent t tests between the two groups. Results: On average, the hybrid group had a follow-up of (42.2±13.4) months (range:27-81 months), and had (4.0±1.8) lengthening procedures with a lengthening interval of (10.5±1.0) months; and the traditional GR group had a follow-up of (45.4±15.2) months (range: 24-76 months), and experienced (4.2±1.9) lengthenings with an interval of (10.8±1.1) months. After the index surgery, the major Cobb angle, C₇ translation, apical vertebral translation, and thoracic kyphosis (TK) had remarkable improvement in both groups. Notably, the hybrid GR group had significantly higher correction rates of major Cobb angle (t=2.348, P=0.027) and TK (t=3.768, P<0.001) than the traditional GR group. At the latest follow-up, the hybrid GR group had remarkably smaller Cobb angle of the major curve than the traditional GR group (t=2.790, P=0.010). At the same time, the hybrid GR group had higher T₁-S₁ height gain than the traditional GR group (t=2.846, P=0.008) after the index surgery. Whereas, non-significant difference was noted between two groups with regards to the T₁-S₁ growth rate during follow-up (t=0.516, P=0.610). Ten complications occurred during the follow-up period, including 2 in the hybrid GR group and 8 in the traditional GR group. The incidence of rod breakage and PJK in the traditional group was 3 and 4 times as high as that of the hybrid GR group, respectively. Conclusions The hybrid growing rod can not only help to improve the correction of spinal deformity but also decrease postoperative complications during follow-up. Moreover, apical short fusion shows no significant influence on spinal growth.

Objective: To evaluate the clinical outcome and health related quality of life in degenerative patients with kyphoscoliosis who underwent S₂AI placement and identify the potential risk factors of pelvic incidence variation postoperative and at last follow-up. Methods: The present study reviewed degenerative patients with kyphoscoliosis who accepted surgery utilized S₂AI screw between January 2015 and January 2019. 25 patients were included in our study, 4 males and 21 females, among these patients, the mean age were 58.84±6.03 years, range from 50-68 years. All patients were conducted long fusion distal to pelvis utilizing S₂AI screws. According to the variation of pelvic incidence at last follow-up, we divided patients into two subgroups: 1) Group I: Patients' pelvic incidence increased more than 5 degree compared with post-operation. 2) Group S: Patients' pelvic incidence varied less than 5 degree compared with post-operation. 13 patient (2 male, 11 female; mean age: 57.23±6.06 years) were categorized into group I, and 12 patients (2 male, 10 female; mean age: 60.58±5.73 years) were categorized into group S.Cobb′s angle, lumbar lordosis(LL), regional kyphosis(RK), sagittal vertical axis(SVA), pelvic incidence(PI), pelvic tilt(PT), sacral slop(SS) were recorded at pre-operation, post-operation and last follow up. The MOS item short from the health survey(SF-36) and Oswestry disability index (ODI) were also recorded at pre-operation and last follow up. Results: There was no statistical difference in gender, age, preoperative Cobb angle, SVA between two groups. In group I, pelvic incidence were decreased postoperatively and increased at the last follow-up (56.92°±14.47° vs 42.69°±14.23° vs 51.62°±14.53°, P<0.05). In group S, pelvic incidence were decreased postoperatively (46.21°±12.26° vs 37.08°±12.99°, P<0.05) and remained stable at the last follow up (37.08°±12.99° vs 37.17°±13.34°, P>0.05). Cobb angle (46.08°±20.52° vs 19.96°±12.64° vs 20.28°±12.01°), RK (32.88°±15.28° vs-12.16°±17.75° vs-11.64°±17.29°), SVA (94.61±92.59 mm vs 25.49±23.89 mm) were improved significantly after surgery and remained stable at the last follow-up. HRQoL score was improved significantly in all patients at the last follow-up compared with preoperative (SF-36 PCS: 36.88±10.89 vs 67.91±10.46, P<0.05; SF-36 MCS: 33.48±10.96 vs 60.19±8.10, P<0.05; ODI: 46.00%±13.54% vs 23.40%±8.86%, P<0.05). Conclusion Pelvic fixation utilizing S2AI screw can provide substantial correction and patients' HRQoL can be improved significantly after surgery. Meanwhile, PI changed at the last follow-up in partial patient. The variation of PI may be associated with the preoperative sagittal malalignment.

The present study reported the case of a patient with degenerative lumbar scoliosis who suffered from postoperative hemorrhage due to lumbar artery injury in corrective osteotomy. The patient presented with decline of blood pressure, extremely low hemoglobin, even after blood transfusion and fluid infusion. Digital subtraction angiography showed lumbar artery injury. Successful control of bleeding and gradually stable vital signs were observed after vascular embolisation. Severe and complex spinal deformity, severe osteophytes in the anterior edge of vertebral body, hypertension, and angiosclerosis were the risk factors of large vascular injuries in spinal osteotomy. Lumbar artery injury should be highly suspected when unknown and progressively aggravating abdominal or back pain, abdominal distention, neurological symptoms of lower limbs, decline of blood pressure, increase of heart rate, decrease of hemoglobin level, continuously bloody drainage or incision bleeding occurred. Vascular embolisation was effective and safe in the management of iatrogenic lumbar artery injury.

Objective: To investigate the differential expression of lncRNA in the serum of ankylosing spondylitis (AS) patients, with the goal of findingnew potential biomarkers for the diagnosis and targeted treatment of AS. Methods: A total of 19 AS patients and 19 age-matched healthy controls treated at Nanjing Drum Tower Hospitalfrom January 2017 to September 2017 were recruited. Average age were 38.74±7.42 (range, 25-51) and 37.00±6.86 (range, 26-50). High-throughput lncRNA sequencing technology was used to detect differently expressed lncRNAs in the serum of 3 AS patients and 3 healthy controls. Target lncRNAs for further validation were selected according to the P values and fold-changes. In the rest of the serum samples (16 AS patients and 16 healthy controls), Trizol-based technique was used to extract total RNA, and after reverse transcription to obtain cDNA, RT-qPCR was preformed to confirm the sequencing results. Results: Using high-throughput lncRNA sequencing, a total of 41 up-regulated and 2 down-regulated lncRNAs were detected in the serum of AS patients. After sorted by the P values, 4 lncRNAswith a fold-change larger than 2 were chosen as the target genes for RT-qPCR (ENST00000365494.1, P=2.6×10^-277, fold-change: 2.05; ENST00000364938.1, P=2.49×10^-77, fold-change: 2.19; ENST 00000363046.1, P=2.67×10^-29, fold-change: 2.51; ENST00000384756.1, P=6.17×10^-21, fold-change: 2.28). RT-qPCR results showed the relative expression of lncRNA ENST00000365494.1 was 1.80±0.22 (P=0.304), lncRNA ENST00000364938.1was 0.78±0.07 (P=0.417), lncRNA ENST00000363046.1was 1.28±0.24 (P=0.793), lncRNA ENST00000384756.1 was 1.52±0.25 (P=0.611)and tendency of up-regulation was found in 3 of them, which was consistent with the sequencing results. However, the difference did not achieve statistical significance. Conclusion Sequencing result could not be confirmed by RT-qPCR with a larger sample size, which implied the differential expression of lncRNA might not exist in the peripheral blood of AS patients, and further studies regarding lncRNA in AS could focus more on its differential expression and function in the focal tissue.