[Application of back-forward Bending CT localization image in the prediction of proximal junctional kyphosis after spinal deformity surgery in adults].

Objective: To investigate the feasibility of predicting proximal junctional kyphosis (PJK) in adults after spinal deformity surgery based on back-forward Bending CT localization images and related predictive indicators. Methods: A retrospective analysis was performed for 31 adult patients with spinal deformity who underwent posterior osteotomy and long-segment fusion fixation between March 2017 and March 2020. There were 5 males and 26 females with an average age of 62.5 years (range, 30-77 years). The upper instrumented vertebrae (UIV) located at T 5 in 1 case, T 6 in 1 case, T 9 in 13 cases, T 10 in 12 cases, and T 11 in 4 cases. The lowest instrumented vertebrae (LIV) located at L 1 in 3 cases, L 2 in 3 cases, L 3 in 10 cases, L 4 in 7 cases, L 5 in 5 cases, and S 1 in 3 cases. Based on the full-length lateral X-ray film of the spine in the standing position before and after operation and back-forward Bending CT localization images before operation, the sagittal sequence of the spine was obtained, and the relevant indexes were measured, including thoracic kyphosis (TK), lumbar lordosis (LL), local kyphosis Cobb angle (LKCA) [the difference between the different positions before operation (recovery value) was calculated], kyphosis flexibility, hyperextension sagittal vertical axis (hSVA), T 2-L 5 hyperextension C 7-vertebral sagittal offset (hC 7-VSO), and pre- and post-operative proximal junctional angle (PJA). At last follow-up, the patients were divided into PJK and non-PJK groups based on PJA to determine whether they had PJK. The gender, age, body mass index (BMI), number of fusion segments, number of cases with coronal plane deformity, bone mineral density (T value), UIV position, LIV position, operation time, intraoperative blood loss, osteotomy grading, and related imaging indicators were compared between the two groups. The hC 7-VSO of the vertebral body with significant differences between groups was taken, and the receiver operating characteristic curve (ROC) was used to evaluate its accuracy in predicting the occurrence of PJK. Results: All 31 patients were followed up 13-52 months, with an average of 30.0 months. The patient's PJA was 1.4°-29.0° at last follow-up, with an average of 10.4°; PJK occurred in 8 cases (25.8%). There was no significant difference in gender, age, BMI, number of fusion segments, number of cases with coronal plane deformity, bone mineral density (T value), UIV position, LIV position, operation time, intraoperative blood loss, and osteotomy grading between the two groups ( P>0.05). Imaging measurements showed that the LL recovery value and T 8-L 3 vertebral hC 7-VSO in the PJK group were significantly higher than those in the non-PJK group ( P>0.05). There was no significant difference in hyperextension TK, hyperextension LL, hyperextension LKCA, TK recovery value, LL recovery value, kyphosis flexibility, hSVA, and T 2-T 7, L 4, L 5 vertebral hC 7-VSO ( P>0.05). T 8-L 3 vertebral hC 7-VSO was analyzed for ROC curve, and combined with the area under curve and the comprehensive evaluation of sensitivity and specificity, the best predictive index was hC 7-L 2, the cut-off value was 2.54 cm, the sensitivity was 100%, and the specificity was 60.9%. Conclusion: Preoperative back-forward Bending CT localization image can be used to predict the occurrence of PJK after posterior osteotomy and long-segment fusion fixation in adult spinal deformity. If the patient's T 8-L 2 vertebral hC 7-VSO is too large, it indicates a higher risk of postoperative PJK. The best predictive index is hC 7-L 2, and the cut-off value is 2.54 cm.

[Preoperative standing to prone spinal-pelvic sagittal parameter changes in old traumatic spinal fractures with kyphosis].

Objective: To investigate the changes in spinal-pelvic sagittal parameters from preoperative standing to prone position in old traumatic spinal fractures with kyphosis. Methods: The clinical data of 36 patients admitted between December 2016 and June 2021 for surgical treatment of old traumatic spinal fractures with kyphosis, including 7 males and 29 females, aged from 50 to 79 years (mean, 63.9 years), were retrospectively analyzed. Lesion segments included 2 cases of T 11, 12 cases of T 12, 2 cases of T 11, 12, 4 cases of T 12 and L 1, 12 cases of L 1, 2 cases of L 2, 1 case of L 2, 3, and 1 case of L 3. The disease duration ranged from 4 to 120 months, with an average of 19.6 months. Surgical procedures included Smith-Petersen osteotomy in 4 cases, Ponte osteotomy in 6 cases, pedicle subtraction osteotomy in 2 cases, and improved fourth level osteotomy in 18 cases; the remaining 6 cases were not osteotomized. The bone mineral density ranged from -3.0 to 0.5 T, with a mean of -1.62 T. The spinal-pelvic sagittal parameters from preoperative standing to prone positions were measured, including local kyphosis Cobb angle (LKCA), thoracic kyphosis (TK), lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), and PI and LL mismatch (PI-LL). The kyphotic flexibility=(preoperative standing LKCA-preoperative prone LKCA)/preoperative standing LKCA×100%. Spinal-pelvic sagittal parameters were compared between standing position and prone position before operation, and Pearson correlation was used to judge the correlation between the parameters of standing position and prone position before operation. Results: When the position changed from standing to prone, LKCA and TK decreased significantly ( P<0.05), while SS, LL, PT, and PI-LL had no significant difference ( P>0.05). Pearson correlation analysis showed that LL was significantly correlated with SS and PI-LL in both standing and prone positions ( P<0.05), and the correlation strength between LL and SS in prone position was higher than that in standing position. In the standing position, LKCA was significantly correlated with SS and PT ( P<0.05). However, when the position changed from standing to prone, the correlation between LKCA and SS and PT disappeared, while PT and PI-LL was positive correlation ( P<0.05). The kyphotic flexibility was 25.13%-78.79%, with an average of 33.85%. Conclusion: For the patients of old traumatic spinal fractures with kyphosis, the preoperative LKCA and TK decrease significantly from standing position to prone position, and the correlation between spinal and pelvic parameters also changed, which should be taken into account in the formulation of preoperative surgical plan.

Optimization of in-brace corrective force in adolescents with Lenke type 5 curve using finite element model.

BACKGROUND: Pelvic parameters have been taken into consideration for the evaluation of the outcomes of bracing in AIS. To discuss the stress required to correct the pelvic deformity related to Lenke5 adolescent idiopathic scoliosis (AIS) by finite element analysis, and provide a reference for the shaping of the pelvic region of the brace. METHODS: An three-dimensional (3D) corrective force on the pelvic area was defined. Computed tomography images were used to reconstruct a 3D model of Lenke5 AIS. Computer-aided engineering software Abaqus was used to implement finite element analysis. By adjusting the magnitude and position of corrective forces, coronal pelvic coronal plane rotation (PCPR) and Cobb angle (CA) of lumbar curve in the coronal plane, horizontal pelvic axial plane rotation, and apical vertebra rotation (AVR) were minimized to achieve the best effect on the spine and pelvic deformity correction. The proposed corrective conditions were divided into three groups: (1) forces applied on X-axis; (2) forces applied both in the X- and Y-axis; and (3) forces applied along the X-, Y-, and Z-axis at the same time. RESULTS: In three groups, CA correction reduced by 31.5%, 42.5%, and 59.8%, and the PCPR changed to 12°, 13°, and 1° from 6.5°, respectively. The best groups of correction forces should simultaneously locate on the sagittal, transverse, and coronal planes of the pelvis. CONCLUSIONS: For Lenke5 AIS, 3D correction forces can sufficiently reduce scoliosis and pelvic asymmetrical state. Force applied along the Z-axis is vital to correct the pelvic coronal pelvic tilt associated with Lenke5 AIS.

Association between body mass index and posterior spine fusion among patients with adolescent idiopathic scoliosis.

INTRODUCTION: Previous studies have found mixed associations between body mass index (BMI) and adolescent idiopathic scoliosis (AIS) incidence and progression. The aim of this study was to examine the association between BMI and the incidence of posterior spine fusion (PSF) among pediatric patients with AIS. METHODS: This was a retrospective cohort study of patients diagnosed with AIS at a single large tertiary care center between January 1, 2014 and December 31, 2020. BMI-for-age percentiles were used to categorize BMI into four categories: underweight (<5th percentile), healthy weight (≥5th to <85th percentile), overweight (≥85th to <95th percentile), and obese (≥95th percentile). Chi-square and t-tests were used to compare distributions of baseline characteristics by incident PSF outcome status. Multivariable logistic regression assessed the association between BMI category at baseline and incident PSF adjusting for sex, age at diagnosis, race/ethnicity, health insurance type, vitamin D supplementation, and low vitamin D levels. RESULTS: A total of 2,258 patients met the inclusion criteria with 2,113 patients (93.6%) who did not undergo PSF during the study period and 145 patients (6.4%) who did undergo PSF. At baseline, 7.3% of patients were categorized as underweight, 73.2% were healthy weight, 10.2% were overweight, and 9.3% were obese. Compared to those in the healthy weight group, there was no significant association between PSF and being underweight (adjusted odds ratio [AOR] 1.64, 95% CI 0.90-2.99, p = 0.107), being overweight (AOR 1.25, 95% CI 0.71-2.20, p = 0.436), or being obese (AOR 1.19, 95% CI 0.63-2.27, p = 0.594). CONCLUSIONS: This study did not find a statistically significant association between underweight, overweight, or obese BMI category and incident PSF among patients with AIS. These findings add to the current mixed evidence on the relationship between BMI and surgical risk and may support the recommendation of conservative treatment to patients regardless of BMI.

Are torso asymmetry and torso displacements in a computer brace model associated with initial in-brace correction in adolescent idiopathic scoliosis?

BACKGROUND: Lack of initial in-brace correction is strongly predictive for brace treatment failure in adolescent idiopathic scoliosis (AIS) patients. Computer-aided design (CAD) technology could be useful in quantifying the trunk in 3D and brace characteristics in order to further investigate the effect of brace modifications on initial in-brace correction and subsequently long-term brace treatment success. The purpose of this pilot study was to identify parameters obtained from 3D surface scans which influence the initial in-brace correction (IBC) in a Boston brace in patients with AIS. METHODS: Twenty-five AIS patients receiving a CAD-based Boston brace were included in this pilot study consisting of 11 patients with Lenke classification type 1 and 14 with type 5 curves. The degree of torso asymmetry and segmental peak positive and negative torso displacements were analyzed with the use of patients' 3D surface scans and brace models for potential correlations with IBC. RESULTS: The mean IBC of the major curve on AP view was 15.9% (SD = 9.1%) for the Lenke type 1 curves, and 20.1% (SD = 13.9%) for the type 5 curves. The degree of torso asymmetry was weakly correlated with patient's pre-brace major curve Cobb angle and negligible correlated with major curve IBC. Mostly weak or negligible correlations were observed between IBC and the twelve segmental peak displacements for both Lenke type 1 and 5 curves. CONCLUSION: Based on the results of this pilot study, the degree of torso asymmetry and segmental peak torso displacements in the brace model alone are not clearly associated with IBC.

Predicting surgical outcome and sagittal alignment change in patients with cervical spondylosis and degenerative kyphosis after anterior cervical discectomy and fusion.

The aim of this study was to forecast the risk factors of poor outcomes and postoperative loss of lordosis or recurrence of kyphosis. In this retrospective study, 101 patients with cervical spondylosis and preoperative kyphosis who underwent anterior cervical discectomy and fusion (ACDF) were enrolled, between June 2015 and June 2019. Patients were grouped according to the recovery rate of Japanese Orthopaedic Association (JOA) score whether more than 50%, and the change of postoperative cervical Cobb angle. There were 22 cases with less than 50% of recovery rate and 35 cases with the worsening of postoperative sagittal alignment (WPSA). Multivariate linear-regression analysis was conducted with the data. Advanced age (p = 0.019), longer duration of symptoms (p = 0.003) and loss of local Cobb angle (LCA) after surgery (p = 0.031) was significantly associated with a poor clinical outcome. A whole kyphosis (p = 0.009), aggravated neck pain after surgery (p = 0.012), preoperative lower thoracic 1 (T1) (p < 0.001), bigger change of C2-7 sagittal vertical axis (SVA) (p = 0.008) and adjacent segment degeneration (ASD) (p = 0.024) was significantly associated with the WPSA. Preoperative health education, nutritional support and early postoperative rehabilitation intervention, in perioperative period, were recommended for patients with advance age, longer duration of symptoms, whole cervical kyphosis and lower T1. Postoperative sagittal malalignment was related to neck pain and ASD after surgery.

Glycerol induced paraspinal muscle degeneration leads to hyper-kyphotic spinal deformity in wild-type mice.

Degenerative spinal disorders, including kyphotic deformity, are associated with a range of degenerative characteristics of the paraspinal musculature. It has therefore been hypothesized that paraspinal muscular dysfunction is a causative factor for degenerative spinal deformity; however, experimental studies demonstrating causative relationships are lacking. Male and female mice received either glycerol or saline injections bilaterally along the length of the paraspinal muscles at four timepoints, each separated by 2 weeks. Immediately after sacrifice, micro-CT was performed to measure spinal deformity; paraspinal muscle biopsies were taken to measure active, passive and structural properties; and lumbar spines were fixed for analysis of intervertebral disc (IVD) degeneration. Glycerol-injected mice demonstrated clear signs of paraspinal muscle degeneration and dysfunction: significantly (p < 0.01) greater collagen content, lower density, lower absolute active force, greater passive stiffness compared to saline-injected mice. Further, glycerol-injected mice exhibited spinal deformity: significantly (p < 0.01) greater kyphotic angle than saline-injected mice. Glycerol-injected mice also demonstrated a significantly (p < 0.01) greater IVD degenerative score (although mild) at the upper-most lumbar level compared to saline-injected mice. These findings provide direct evidence that combined morphological (fibrosis) and functional (actively weaker and passively stiffer) alterations to the paraspinal muscles can lead to negative changes and deformity within the thoracolumbar spine.

[Multivariate correlation analysis of T1S and C7S].

OBJECTIVE: To determine whether C7 angles (C7 slope, C7S) could replace T1 angles (T1 slope, T1S) by correlation analysis of T1S and C7S. METHODS: A total of 442 patients from July 2015 to July 2020 in outpatient and inpatient department were enrolled retrospectively, and 259 patients who could identify the upper endplate of T1 were screened out . Of them, there were 145 males and 114 females, aged from 20 to 83 years old with an average of (58.6±11.2) years, including 163 patients with cervical spine surgery and 96 non-surgical patients. Patients were stratified by sex, age, cervical kyphosis, cervical alignment imbalance, and cervical spine surgery. These 259 patients included 145 cases in the male group, 114 cases in the female group;76 cases in the youth group (<40 years old), 109 cases in the middle-aged group (40 to 60 years old), and 74 cases in the elderly group(>60 years old); 92 cases in the cervical kyphosis group, 167 cases in the non-kyphosis group;51 cases in the cervical sequence imbalance group, 208 cases in the non-imbalance group;163 cases in the cervical surgery group, 96 cases in the non-operation group. The correlations of C7S and T1S in various modalities groups were analyzed. RESULTS: Of 442 patients, the recognition rate of upper endplate of T1 was 58.6%(259/442), and that of C7 was 90.7%. The mean T1S and C7S of the 259 patients were (24.5±8.0)° [(25.9±7.7)° in the male group and (23.7±6.9)° in the female group] and (20.8±7.3)° [(22.5±7.5)° in the male group and(19.7±5.8)° in the female group], respectively. The total correlation coefficient between C7S and T1S was r=0.89, R2=0.79, and the linear regression equation was T1S=0.91×C7S+4.35. In the above general information and the grouping of deformity factors, T1S was highly correlated with C7S(r value 0.85 to 0.92, P<0.05). CONCLUSION: There is a high correlation between T1S and C7S in different factor groups. For cases where T1S cannot be measured, C7S can be used to provide guidance and reference for evaluating the sagittal balance of the spine, analyzing the condition, and formulating surgical plans.

[Treatment of stage â ¡-â ¢ Kümmell disease with robot-assisted bone cement-augmented pedicle screw fixation].

OBJECTIVE: To evaluate the early clinical efficacy of robot-assisted percutaneous short-segment bone cement-augmented pedicle screw fixation in the treatment of stageⅡ-Ⅲ Kümmell disease. METHODS: The clinical data of 20 patients with stageⅡ-Ⅲ Kümmell's disease who underwent robot-assisted percutaneous bone cement-augmented pedicle screw fixation between June 2017 and January 2021 were retrospectively analyzed. There were 4 males and 16 females, aged from 60 to 81 years old with an average age of (69.1±8.3) years. There were 9 cases of stageⅡand 11 cases of stage Ⅲ, all of which were single vertebral lesions, including 3 cases of T11, 5 cases of T12, 8 cases of L1, 3 cases of L2, and 1 case of L3. These patients did not exhibit symptoms of spinal cord injury. The operation time, intraoperative blood loss, and complications were recorded. The position of pedicle screws and the filling and leakage of bone cement in gaps were observed using postoperative CT 2D reconstruction. The data of the visual analogue scale (VAS), Oswestry disability index (ODI), kyphosis Cobb angle, wedge angle of the diseased vertebra, and anterior and posterior vertebral height on lateral radiographs were statistically analyzed preoperatively, 1 week postoperatively, and at the final follow-up. RESULTS: Twenty patients were followed up for 10 to 26 months, with an average follow-up of (16.0±5.1) months. All operations were successfully completed. The surgical duration ranged from 98 to 160 minutes, with an average of (122±24) minutes. The intraoperative blood loss ranged from 25 to 95 ml, with an average of (45±20) ml. There were no intraoperative vascular nerve injuries. A total of 120 screws were inserted in this group, including 111 screws at grade A and 9 screws at grade B according to the Gertzbein and Robbins scales. Postoperative CT indicated that the bone cement was well-filled in the diseased vertebra, and cement leakage occurred in 4 cases. Preoperative VAS and ODI were (6.05±0.18) points and (71.10±5.37)%, respectively, (2.05±0.14) points and (18.57±2.77)% at 1 week after operation, and (1.35±0.11) points and (15.71±2.12) % at final follow-up. There were significant differences between postoperative 1 week and preoperative, and between final follow-up and postoperative 1 week(P<0.01). Anterior and posterior vertebral height, kyphosis Cobb angle, and wedge angle of the diseased vertebra were(45.07±1.06)%, (82.02±2.11)%, (19.49±0.77) °, and (17.56±0.94) ° preoperatively, respectively, (77.00±0.99)%, (83.04±2.02)%, (7.34±0.56) °, and (6.15±0.52) ° at 1 week postoperatively, and (75.13±0.86)%, (82.39±0.45)%, (8.38±0.63) °, and (7.09±0.59) ° at the final follow-up. CONCLUSION: Robot-assisted percutaneous short-segment bone cement-augmented pedicle screw fixation demonstrates satisfactory short-term efficacy in treating stageⅡ-Ⅲ Kümmell's disease as an effective minimally invasive alternative. However, longer operation times and strict patient selection criteria are necessary, and long-term follow-up is required to determine its lasting effectiveness.

Balance Control and Plantar Pressure Distribution in Hyperkyphotic Adolescent and Young Adults.

AIM: To assess differences in static/dynamic balance and plantar pressure distribution (PPD) in hyperkyphotic adolescents and young adults based on sagittal spinopelvic alignment changes. MATERIAL AND METHODS: Twelve hyperkyphotic patients and 12 normal subjects were included in the study group and control group, respectively. Lateral spine X-rays were used to evaluate spinopelvic parameters, thoracic kyphosis, lumbar lordosis (LL), and sagittal vertical axis offsets. A Balance Master device was used to evaluate the balance and postural control of subjects, and an EMED pedobarography device was used to record dynamic PPDs. Radiologic parameters, center of pressure (COP) velocity, COP alignment, and PPDs were compared in both groups to determine significance. RESULTS: A positive correlation was found between kyphosis and lordosis (r = 0.573, p=0.03) in the study group. No significant difference was found in COP alignment and mean sway velocity between the two groups (p > 0.05). Statistically significant differences were found in the endpoint excursion values in the forward direction between groups in terms of dynamic balance measurement (p=0.09). The dynamic pedobarographic measurements did not reveal any intergroup differences (p < 0.05). CONCLUSION: Delayed balance control may be observed during forward reach in hyperkyphotic adolescents and young adults. Compensatory LL may be effective to maintain normal gravity projections, static balance control, and PPDs as a response to thoracic hyperkyphosis.

Screening of adolescent idiopathic scoliosis using generative adversarial network (GAN) inversion method in chest radiographs.

OBJECTIVE: Conventional computer-aided diagnosis using convolutional neural networks (CNN) has limitations in detecting sensitive changes and determining accurate decision boundaries in spectral and structural diseases such as scoliosis. We devised a new method to detect and diagnose adolescent idiopathic scoliosis in chest X-rays (CXRs) employing the latent space's discriminative ability in the generative adversarial network (GAN) and a simple multi-layer perceptron (MLP) to screen adolescent idiopathic scoliosis CXRs. MATERIALS AND METHODS: Our model was trained and validated in a two-step manner. First, we trained a GAN using CXRs with various scoliosis severities and utilized the trained network as a feature extractor using the GAN inversion method. Second, we classified each vector from the latent space using a simple MLP. RESULTS: The 2-layer MLP exhibited the best classification in the ablation study. With this model, the area under the receiver operating characteristic (AUROC) curves were 0.850 in the internal and 0.847 in the external datasets. Furthermore, when the sensitivity was fixed at 0.9, the model's specificity was 0.697 in the internal and 0.646 in the external datasets. CONCLUSION: We developed a classifier for Adolescent idiopathic scoliosis (AIS) through generative representation learning. Our model shows good AUROC under screening chest radiographs in both the internal and external datasets. Our model has learned the spectral severity of AIS, enabling it to generate normal images even when trained solely on scoliosis radiographs.

A Modified Unilateral Extrapedicular Approach Applied to Percutaneous Kyphoplasty to Treat Lumbar Osteoporotic Vertebral Compression Fracture: A Retrospective Analysis.

BACKGROUND: In recent years, many extrapedicular puncture methods have been applied to percutaneous kyphoplasty (PKP) in the treatment of osteoporotic vertebral compression fractures (OVCFs). However, these techniques were generally complex and had the risk of some puncture-related complications, which greatly limited the wide applications in PKP. Finding a safer and more feasible extrapedicular puncture method was rather important. OBJECTIVES: To evaluate the treatment effect of modified unilateral extrapedicular PKP in patients with lumbar OVCFs clinically and radiologically. STUDY DESIGN: Retrospective study. SETTING: Department of Orthopedic Surgery, an affiliated hospital of a medical university. METHODS: Patients who were treated by modified unilateral extrapedicular PKP in our institution, from January 2020 to March 2021, were retrospectively enrolled. The degree of pain relief and functional recovery were evaluated by the Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI), respectively. Radiologic results were assessed including anterior vertebral height (AVH) and kyphotic angle. In addition, volumetric analysis was performed to evaluate bone cement distribution. And the intraoperative data and complications were also recorded. RESULTS: A total of 48 patients with lumbar OVCFs were successfully treated by modified unilateral extrapedicular PKP. All patients experienced a significant decrease in VAS and ODI scores after surgery (P < 0.01) and maintained the statistical significance until the last follow-up (P < 0.01), as well as significant AVH restoration (P < 0.01) and kyphotic angle correction (P < 0.01) compared with preoperative corresponding values. Volumetric analysis showed that all cases of bone cement diffused across the midline of the vertebral body (VB), in which 43 patients (89.6%) presented optimal contralateral distribution with good or excellent bone cement spread. In addition, 8 patients (16.7%) experienced asymptomatic cement leakage, and no other severe complications, such as injuries to segmental lumbar arteries and nerve roots, were found. LIMITATIONS: A noncontrol study with a small patient population and short follow-up duration. CONCLUSIONS: Modified unilateral extrapedicular PKP, in which the puncture trajectory was advanced through the bottom of Kambin's triangle to or across the midline of VB for proper bilateral cement distribution, greatly alleviated back pain and restored the morphology of fractured vertebrae. It seemed to be a safe and effective alternative applied to treat lumbar OVCFs with appropriate patient selection.

Clinical efficacy of different open approaches in the surgical treatment of thoracolumbar tuberculosis: a single-center retrospective comparative study.

OBJECTIVE: To assess the clinical efficacy of three different surgical approaches in the treatment of thoracolumbar tuberculosis. METHODS: A total of 138 patients with thoracolumbar tuberculosis treated by open surgery were retrospectively analyzed. The surgical methods were divided into anterior, posterior and anterior-posterior combined. The hospital stays, amount of bleeding, operative time, preoperative, postoperative and last follow-up ESR, CRP, Frankel score, ODI, VAS, correction and loss rate of kyphosis, fusion rate and complications were recorded and analyzed. RESULTS: The average follow-up was 66 months. The average hospital stay, operative time and amount of bleeding of the anterior-posterior combined group were higher than other groups (P < 0.05). ESR and CRP of all patients were reduced postoperatively (P < 0.05). No significant difference among the three groups was found in the postoperative correction angle of kyphosis (P < 0.05), while the pre- and postoperative Cobb angle as well as correction rate had significant differences. The posterior approach could achieve better correction, and the loss of correction was more in the anterior group, 40.9 percent of patients performed correction loss. The Frankel score, VAS and ODI were significantly reduced among the three groups, and the incidence rate of complications of the anterior approach was lower than the other groups, with a significant difference (P < 0.05). CONCLUSION: The anterior approach has more advantages and fewer complications, which is supposed to give preference to and could not be replaced by the posterior and anterior-posterior combined approach.

Prediction formulae of sagittal alignment in thoracolumbar kyphosis secondary to ankylosing spondylitis after osteotomy.

To construct and validate prediction formulae of sagittal alignment in thoracolumbar kyphosis secondary to ankylosing spondylitis (AS) after osteotomy. A total of 115 AS patients who suffered from thoracolumbar kyphosis and underwent osteotomy were enrolled, with 85 patients in derivation group and 30 patients in validation group. Radiographic parameters were measured on lateral radiographs, including thoracic kyphosis, lumbar lordosis (LL), T1 pelvic angel (TPA), sagittal vertical axis (SVA), osteotomized vertebral angle, pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and PI and LL mismatch (PI-LL). Prediction formulae of SS, PT, TPA and SVA were established; and their effectiveness was evaluated. There was no significant difference in baseline characteristics between the two groups (p > 0.05). In derivation group, LL and PI-LL were correlated with SS, and were then used to establish the prediction formula of SS[SS = - 12.791-0.765 × (LL) + 0.357 × (PI-LL), R2 = 68.3%]; PI and PI-LL were correlated with PT, and the prediction formula of PT were thus established[PT = 12.108 + 0.402 × (PI-LL) + 0.252 × (PI), R2 = 56.8%]; PT, PI-LL and LL were correlated with TPA, and were used to establish the prediction formula of TPA[TPA = 0.225 + 0.597 × (PT) + 0.464 × (PI-LL)-0.161 × (LL), R2 = 87.4%]; PT, PI-LL and age were correlated with SVA, and were used to establish the prediction formula of SVA[SVA = 36.157 + 2.790 × (PI-LL) + 1.657 × (Age)-1.813 × (PT), R2 = 41.5%]. In validation group, the predictive SS, PT, TPA and SVA were basically consistent with corresponding real values; and the mean error between predictive values and real values was of 1.3° in SS, 1.2° in PT, 1.1° in TPA and 8.6 mm in SVA. Postoperative SS, PT, TPA and SVA could be predicted with PI and the planned LL and PI-LL using prediction formulae, providing a method for AS kyphosis to plan postoperative sagittal alignment. Change of pelvic posture after osteotomy was quantitatively evaluated using the formulae.

Recurrence of Local Kyphosis After Percutaneous Kyphoplasty: The Neglected Injury of the Disc-Endplate Complex.

Background: Recurrent of local kyphosis after percutaneous kyphoplasty (PKP) is rarely reported and discussed. Literatures reported that re-kyphosis is usually a consequence of refractures of augmented or adjacent vertebra. However, whether re-kyphosis should be considered as a complication of refractures and has an impact on clinical efficacy of PKP during follow-up time is unknown. The purpose of this study is to evaluate the related risk factors and clinical significance of the recurrent of local kyphosis in osteoporotic vertebral fracture (OVF) patients without refractures. Patients and Methods: A total of 143 patients who underwent single-level PKP were recruited and assigned into the re-kyphosis group and non-re-kyphosis group. Clinical and radiographic data were collected and compared between the two groups. Then, multivariate logistic regression analyses were conducted to identify the related risk factors. Results: During follow-up, 16 of the 143 patients presented postoperative re-kyphosis. The average local kyphosis angle increased from 11.81±8.60° postoperatively to 25.13±8.91° at the final follow-up which showed a statistically significant difference (p<0.05). Both groups had significant improvements in postoperative visual analogue scale (VAS) and Oswestry Disability Index (ODI) scores compared to their preoperative values (p<0.05). However, in the re-kyphosis group at final follow-up, the VAS and ODI scores showed worsening compared to the postoperative scores. Logistic regression analysis showed that disc-endplate complex injury (OR=17.46, p=0.003); local kyphosis angle correction (OR=1.84, p<0.001); and vertebral height restoration (OR=1.15, p=0.003) were risk factors for re-kyphosis. Conclusion: Re-kyphosis is not rare in patients with osteoporotic vertebral fracture and tends to have an inferior prognosis following PKP surgery. Patients with disc-endplate complex injury and more correction of vertebral height and kyphosis angle are at a higher risk for re-kyphosis after PKP surgery than others.

Association Among Complete Blood Count Parameters, Bone Mineral Density, and Cobb Angle in Cases of Adolescent Idiopathic Scoliosis.

BACKGROUND Improving the quality of life of scoliosis patients with appropriate preventive measures is critical. This study aimed to investigate the relationships among bone mass, Cobb angle, and complete blood count (CBC) parameters in patients with scoliosis. MATERIAL AND METHODS This joint study was conducted by the pediatric department and orthopedics clinics, which used the medical records of patients aged 10-18 years between 2018 and 2022. Patients were divided into 3 groups according to the Cobb angle. Patient blood count levels from medical records and bone mineral density (BMD) Z scores (g/cm²) were compared among groups. Notably, BMD Z scores were calculated using a (BMD) dataset from local Turkish children after adjusting for height and age. RESULTS A total of 184 individuals (120 females, 64 males) were included in the study. There were statistically significant differences among the groups in platelet-to-lymphocyte ratio (PLR). Significant differences in DXA Z scores among groups were found. There was a significantly strong and positive correlation between DXA Z scores and all CBC parameters in patients with severe scoliosis. CONCLUSIONS This study found that CBC parameters can predict BMD in adolescents. Furthermore, the association between vitamin D deficiency and low BMD may contribute to the follow-up of body adaptation in patients with scoliosis receiving conservative treatment.

Application of combined anterior and posterior approaches for the treatment of cervical tuberculosis with anterior cervical abscess formation and kyphosis using a Jackson operating table: a case report and literature review.

BACKGROUND: There have been insufficient reports to date regarding the treatment of cervical spinal tuberculosis, and the optimal surgical approaches to treating this condition have yet to be established. CASE REPORT: This report describes the treatment of a case of tuberculosis associated with a large abscess and pronounced kyphosis through the use of a combined anterior and posterior approach with the aid of the Jackson operating table. This patient did not exhibit any sensorimotor abnormalities of the upper extremities, lower extremities, or trunk, and presented with symmetrical bilateral hyperreflexia of the knee tendons, while being negative for Hoffmann's sign and Babinski's sign. Laboratory test results revealed an erythrocyte sedimentation rate (ESR) of 42.0 mm/h and a C-reactive protein (CRP) of 47.09 mg/L. Acid-fast staining was negative, and spine magnetic resonance imaging revealed the destruction of the C3-C4 vertebral body and a posterior convex deformity of the cervical spine. The patient reported a visual analog pain score (VAS) of 6, and exhibited an Oswestry disability index (ODI) score of 65. Jackson table-assisted anterior and posterior cervical resection decompression was performed to treat this patient, and at 3 months post-surgery the patient's VAS and ODI scores were respectively reduced to 2 and 17. Computed tomography analyses of the cervical spine at this follow-up time point revealed good structural fusion of the autologous iliac bone graft with internal fixation and improvement of the originally observed cervical kyphosis. CONCLUSIONS: This case suggests that Jackson table-assisted anterior-posterior lesion removal and bone graft fusion can safely and effectively treat cervical tuberculosis with a large anterior cervical abscess combined with cervical kyphosis, providing a foundation for future efforts to treat spinal tuberculosis.

Does Progesterone Affect Perioperative Blood Loss during Posterior Spinal Fusion Surgeries in Female Patients with Adolescent Idiopathic Scoliosis? A Retrospective Study.

OBJECTIVE: Menstruation is considered a contraindication for elective surgery for higher operative blood loss. Progesterone is often used to postpone menstruation to avoid surgery during menstruation. This study aimed to explore whether using progesterone to postpone menstruation affects perioperative blood loss and complications in female patients with adolescent idiopathic scoliosis (AIS) who underwent posterior spinal fusion (PSF) surgery. METHODS: A retrospective study was performed for female patients diagnosed with AIS who underwent PSF surgery between March 2013 and January 2021. Patients scheduled to undergo PSF surgery from 2 days before menstruation to 3 days after menstruation were treated with progesterone preoperatively. The patients were divided into two groups according to progesterone use (progesterone injection group; control group). Demographic and surgical data including intraoperative blood loss (IBL), normalized blood loss (NBL), total blood loss (TBL), transfusion rate, perioperative complications, postoperative drainage time, postoperative hospital stay, and preoperative coagulation function data were collected. RESULTS: A total of 206 patients were included in the study. Among them, the progesterone injection group included 41 patients, with an average age of 14.8 years. While the control group included 165 patients, with an average age of 14.9 years. The two groups were matched for age, height, weight, operation time, Risser sign, correction rate, mean curve Cobb angle, bending Cobb angle, number of internal fixations, and number of fused levels (all P > 0.05). Regarding coagulation function, no significant differences were found in thrombin time, activated partial thromboplastin time, fibrinogen, prothrombin time, and platelet count between the two groups (all P > 0.05). IBL, NBL, and TBL were higher in progesterone injection group; however, the difference was nonsignificant (all P > 0.05). Transfusion rate, perioperative complications, postoperative drainage time, and postoperative hospital stay were not statistically different between groups (all P > 0.05). CONCLUSION: Intramuscular injection of progesterone to avoid menstruation during PSF surgery did not affect perioperative blood loss and complications in AIS patients. It may be a safe method for AIS patients to avoid menstrual problems affecting the operation time and receive PSF surgery as scheduled.

Radiographic Outcomes of Conservative and Operative Treatment in Isolated L1 Fractures.

Background and Objectives: The adequate therapy of thoracolumbar fractures in the elderly population is still controversially discussed. The aim of this study was to evaluate and compare the results of conservatively and surgically treated younger (≤60a) and elderly patients (>60a) with fractures of L1. Materials and Methods: Patients (231) with isolated L1 fractures were included and treated at the University Clinic of Orthopedics and Trauma Surgery, Division of Trauma Surgery, Medical University of Vienna, during the observation period of 2012-2018. Results: Conservative treatment led to a significant increase in the vertebral and bi-segmental kyphosis angle in both age groups (young vertebral: p = 0.007; young bi-segmental: p = 0.044; old vertebral: p = 0.0001; old bis-segmental: p = 0.0001). A significant reduction in the vertebral angle in both age groups was achieved after operative treatment (young: p = 0.003, old: p = 0.007). The bi-segmental angle did not significantly improve after surgery in both age groups (≤60a: p = 0.07; >60a: p = 1.0). Conclusions: The study shows that conservative treatment does not seem to be sufficient for a correction of radiological parameters in young and elderly patients. In contrast, operative treatment led to a significant improvement of the vertebral kyphosis angle, without changing the bi-segmental kyphosis angle. These results suggest a greater benefit from operative treatment in patients ≤ 60a than in older patients.