Perioperative complications of en bloc resection and anterior column reconstruction for thoracic and lumbar spinal tumors.

PURPOSE: To evaluate the perioperative clinical outcomes of en bloc resection and anterior column reconstruction for thoracolumbar spinal tumors. METHODS: This study conducted a retrospective analysis of prospective data collection of 86 consecutive patients, including 40 males and 46 females, with an average age of 39 years (ranged from 10 to 71 years). There were 35 cases of a malignant primary tumor,42 cases of an aggressive benign tumor, and nine cases of metastases. The main lesions were located in 65 cases of thoracic spine, 17 cases of lumbar spine, and 4 cases of thoracolumbar spine. Tumors involved one level in 45 patients, two levels in 12 patients, three levels in 21 patients, four levels in five patients, five levels in two patients, and six levels in one patient. RESULTS: According to the Weinstein-Boriani-Biagini surgical staging system, all patients achieved en bloc resections, including 74 cases of total en bloc spondylectomy and 12 cases of sagittal resections. The mean surgical time was 559 min (210-1208 min), and the mean total blood loss was 1528 ml (260-5500 ml). A total of 122 complications were observed in 62(72.1%) patients, of which 18(20.9%) patients had 25 major complications and one patient (1.2%) died of complications. The combined approach (P = 0.002), total blood loss (P = 0.003), staged surgery (P = 0.004), previous surgical history (P = 0.045), the number of involved vertebrae (P = 0.021) and lumbar location (P = 0.012) were statistically significant risk factors for major complication. When all above risk factors were incorporated in multivariate analysis, only the combined approach (P = 0.052) still remained significant. CONCLUSIONS: En bloc resection and anterior column reconstruction is accompanied by a high incidence of complications, especially when a combined approach is necessary.

[Clinical outcomes of 3D-printing stand-alone artificial vertebral body in anterior cervical surgeries].

OBJECTIVE: To explore the short-term outcomes of 3D-printing stand-alone artificial vertebral body (AVB) in the surgical procedure of anterior cervical corpectomy and fusion (ACCF). METHODS: Following the proposal of IDEAL (idea, development, exploration, assessment, and long-term follow-up) framework, we designed and conducted this single-armed, retrospective cohort study. The patients with cervical spondylotic myelopathy were recruited, and these patients exclusively received the surgical procedure of single-level ACCF in our single center. After the process of corpectomy, the size was tailored using different trials and the most suitable stand-alone AVB was then implanted. This AVB was manufactured by the fashion of 3D-printing. Two pairs of screws were inserted in an inclined way into the adjacent vertebral bodies, to stabilize the AVB. The participants were regularly followed-up after the operation. Their clinical data were thoroughly reviewed. We assessed the neurological status according to Japanese Orthopedic Association (JOA) scale. We determined the fusion based on imaging examination six months after the operation. The recorded clinical data were analyzed using specific software and they presented in suitable styles. Paired t test was employed in comparison analysis. RESULTS: In total, there were eleven patients being recruited eventually. The patients were all followed up over six months after the operation. The mean age of the cohort was (57.2±10.2) years. The mean operation time was (76.1±23.1) min and the median bleeding volume was 150 (100, 200) mL. The postoperative course was uneventful for all the cases. Dysphagia, emergent hematoma, and deterioration of neurological function did not occur. Mean JOA scores were 13.2±2.2 before the operation and 16.3±0.8 at the final follow-up, which were significantly different (P < 0.001). The mean recovery rate of neurological function was 85.9%. By comparing the imaging examinations postoperatively and six months after the operation, we found that the average subsidence length was (1.2±1.1) mm, and that there was only one cases (9.1%) of the severe subsidence (>3 mm). We observed significant improvement of cervical lordosis after the operation (P=0.013). All the cases obtained solid fusion. CONCLUSION: 3D-printing stand-alone AVB presented favorable short-term outcome in one-level ACCF in this study. The fusion rate of this zero-profile prosthesis was satisfactory and the complication rate was relatively low.

Complications and prognosis of primary thoracic and lumbar giant cell tumors treated by total tumor resection.

BACKGROUND: Spinal giant cell tumor (SGCT) is a relatively rare primary tumor. En bloc resection is the preferred surgical procedure for it due to its aggressiveness, meanwhile leading to more complications. We reported the characteristics of perioperative complications and local control of total tumor resection including en bloc resection and piecemeal resection for primary thoracic and lumbar spinal giant cell tumors in a single center over 10 years. METHODS: This is a retrospective cross-sectional and cohort study. Forty-one consecutive patients with SGCTs who underwent total tumor resection from 2010 to 2020 at our institution and were followed up for at least 24 months were reviewed. Surgery data, complication characteristics and local tumor control were collected and compared by different surgical procedure. RESULTS: Forty-one patients were included, consisting of 18 males and 23 females, with a mean age of 34.2 years. Thirty-one had thoracic vertebra lesions, and 10 had lumbar vertebra lesions. Thirty-five patients were primary cases, and 6 patients were recurrent cases. Eighteen patients were treated by total en bloc spondylectomy (TES), 12 patients underwent en bloc resection according to WBB surgical system, and 11 patients underwent piecemeal resection. The average surgical time was 498 min, and the mean estimated blood loss was 2145 ml. A total of 58 complications were recorded, and 30 patients (73.2%) had at least one perioperative complication. All patients were followed up after surgery for at least 2 years. A total of 6 cases had postoperative internal fixation failure, and 4 cases presented local tumor recurrence (9.8%). CONCLUSIONS: Although the surgical technique is difficult and accompanied by a high rate of perioperative complications, en bloc resection can achieve favorable local control in SGCT. When it is too difficult to complete en bloc resection, thoroughly piecemeal resection without residual is also acceptable, given the relatively low recurrence rate.

Normative values of cervical sagittal alignment according to global spine balance: based on 126 asymptomatic Chinese young adults.

PURPOSE: To explore the normal distribution of cervical sagittal alignment and the relationship between cervical alignment and global spine balance in asymptomatic young adults. METHODS: A total of 67 males and 59 females aged from 18 to 30 years old were recruited from 11/2011 to 12/2014. The C0-C2 angle, disk angles from C2-C3 to C6-C7, vertebral angles from C3 to C7, T1 slope, thoracic kyphosis (TK), lumbar lordosis, pelvic incidence, sacral slope, C2-C7 sagittal vertical axis (SVA), center of gravity of head to C7 SVA (CGH-C7SVA), C7-S1SVA were measured and statistically analyzed. The Roussouly classification was utilized. RESULTS: Mean value of C0-C7 was 26.0° ± 12.8°, composed of 15.2° ± 6.7° for C0-C2, 9.1° ± 12.1° for sum of disk angles from C2-C3 to C6-C7, and 1.4° ± 10.2° for sum of vertebral angles from C3 to C7. C2-C7SVA (18.6 mm ± 7.9 mm) and CGH-C7SVA (22.9 mm ± 12.3 mm) were offset ideally by C7-S1SVA (-21.6 mm ± 31.0 mm). Significant difference was found between cervical alignment of different Roussouly types (p < 0.01). There was significant correlation between cervical alignment and T1 slope (p < 0.01), TK (p < 0.01). There was significant correlation between adjacent segmental angles from T1 slope up to C0-C2 angle (p < 0.05). CONCLUSION: Normative values of each vertebral angle and disk angle were established. The cervical lordosis occurred mainly at C0-C2 and disk levels, which was influenced by parameters of other parts of the spine, such as T1 slope, TK and the Roussouly classification. There was significant correlation between adjacent disk angles. LEVEL OF EVIDENCE I: Diagnostic: individual cross-sectional studies with the consistently applied reference standard and blinding.

Postoperative alterations of sagittal cervical alignment and risk factors for cervical kyphosis in 124 Lenke 1 adolescent idiopathic scoliosis patients.

BACKGROUND: This study aims to analyze postoperative changes of cervical sagittal curvature and to identify independent risk factors for cervical kyphosis in Lenke type 1 adolescent idiopathic scoliosis (AIS) patients. METHODS: A total of 124 AIS patients who received all-pedicle-screw instrumentation were enrolled. All patients were followed up for at least 2 years. The following parameters were measured preoperatively, immediately after the operation, and at the last follow-up: pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), global thoracic kyphosis (GTK), proximal thoracic kyphosis (PrTK), T1-slope, cervical lordosis (CL), McGregor slope (McGS), sagittal vertical axis (SVA), C2-7 SVA (cSVA), and main thoracic angle (MTA). Statistical analysis was performed to evaluate postoperative alterations of and correlations between the parameters and to identify risk factors for cervical kyphosis. Statistical significance was set at P < 0.05. RESULTS: After the operation, PrTK and T1-slope significantly increased (3.01 ± 11.46, 3.8 ± 10.76, respectively), cervical lordosis improved with an insignificant increase (- 2.11 ± 13.47, P = 0.154), and MTA, SS, and LL decreased significantly (- 33.68 ± 15.35, - 2.98 ± 8.41, 2.82 ± 9.92, respectively). Intergroup comparison and logistic regression revealed that preoperative CK > 2.35° and immediate postoperative GTK < 27.15° were independent risk factors for final cervical kyphosis, and △T1-slope < 4.8° for a kyphotic trend. CONCLUSIONS: Postoperative restoration of thoracic kyphosis, especially proximal thoracic kyphosis, and T1-slope play a central role in cervical sagittal compensation. Preoperative CK, postoperative small GTK, and insufficient △T1-slope are all independent risk factors for cervical decompensation.

The morphological and clinical significance of developmental cervical stenosis.

PURPOSE: To investigate the difference of intra-dural space for spinal cord in magnetic resonance imaging between patients with and without developmental cervical stenosis and its clinical significance. METHODS: 445 patients with cervical spondylotic myelopathy who had decompression surgeries were recruited. Based on their lateral radiographs, they were divided into stenosis and non-stenosis groups. On the magnetic resonance images, the ratio of the sagittal diameter of the dural sac to that of the vertebral body was measured and calculated as MRI Pavlov ratio at mid-vertebral level on sagittal images, and the ratio of the transverse area of the spinal cord to that of the dural sac was measured and calculated as occupation ratio on axial images from C3 to C7. The two ratios were compared between the two groups. We examined the correlations of the Pavlov ratio and the MRI Pavlov ratio between different vertebral levels. The correlation between the Pavlov ratio of each level and its corresponding MRI Pavlov ratio was also examined. The stenosis group was further divided into space-reserving and non-space-reserving subgroups based on their occupation ratios; then, clinical parameters were compared between the two subgroups to determine the clinical significance of the reserving space. RESULTS: The MRI Pavlov ratio of the stenosis group was significantly smaller at C3-C7 (P < 0.001), while the occupation ratio was larger without significance. The Pavlov and MRI Pavlov ratios were correlated significantly at different levels (P < 0.001). The Pavlov ratio correlated significantly with its corresponding MRI Pavlov ratio at each level (P < 0.001). For space-reserving subgroup, the recovery rate was lower (P < 0.05) than that for non-space-reserving group, and was higher in anterior approach than that in posterior approach (P < 0.05). CONCLUSIONS: Developmental cervical stenosis is associated with a smaller sagittal diameter of dural sac, but does not lead to a significant decrease of intra-dural space available for the cord. For patients with normal intra-dural space, the recovery after anterior decompression surgery was better.

Comparison of En Bloc Resection and Intralesional Excision for Re-resection of Giant Cell Tumors of the Spine.

OBJECTIVE: Re-resection of spinal giant cell tumors is an exceedingly difficult procedure. Moreover, the prognosis of patients with en bloc resection or intralesional excision for re-resection has rarely been reported. This study aimed to compare the prognostic value of en bloc resection with that of intralesional excision in patients undergoing re-resection for giant cell tumors of the spine. METHODS: This retrospective analysis evaluated patients who underwent revision surgeries for relapse of giant cell tumors of the spine at our center between January 2005 and January 2021. Local progression-free survival represents the duration between en bloc resection or intralesional excision and tumor recurrence. Neurological recovery, survival rates, local control, and complications were evaluated. The Kaplan-Meier estimator was used for survival analysis. RESULTS: A total of 22 patients (nine men and 13 women) with a mean age of 34.1 (range 19-63) years were included. Significant statistical differences were found in the local tumor recurrence rate between patients treated with en bloc resection and those treated with intralesional excision (p < 0.05). The 5- and 10-year local progression-free survival rates were both 90% in the en bloc resection group, while in the intralesional excision group, the 5-year local progression-free survival rate was 80% with a 10-year rate of 45.7%. The en bloc resection group had a lower local tumor recurrence rate than that of the intralesional excision group (p < 0.05), but the former had a higher rate of complications (p = 0.015). CONCLUSIONS: This study revealed a low local recurrence rate in patients who underwent en bloc resection for giant cell tumors, while the perioperative complication rate was high.

mRNA vaccine development and applications: A special focus on tumors (Review).

Cancer is characterized by unlimited proliferation and metastasis, and traditional therapeutic strategies usually result in the acquisition of drug resistance, thus highlighting the need for more personalized treatment. mRNA vaccines transfer the gene sequences of exogenous target antigens into human cells through transcription and translation to stimulate the body to produce specific immune responses against the encoded proteins, so as to enable the body to obtain immune protection against said antigens; this approach may be adopted for personalized cancer therapy. Since the recent coronavirus pandemic, the development of mRNA vaccines has seen substantial progress and widespread adoption. In the present review, the development of mRNA vaccines, their mechanisms of action, factors influencing their function and the current clinical applications of the vaccine are discussed. A focus is placed on the application of mRNA vaccines in cancer, with the aim of highlighting unique advances and the remaining challenges of this novel and promising therapeutic approach.

Absence of causal association between Vitamin D and bone mineral density across the lifespan: a Mendelian randomization study.

Vitamin D deficiency is a candidate risk factor for osteoporosis, characterized by decreased bone mineral density (BMD). We performed this two-sample Mendelian randomization (MR) analysis to investigate the causal effect of vitamin D on BMD. We extracted 143 single-nucleotide polymorphisms from a recent GWAS on 417,580 participants of European ancestry as instrumental variables, and used summary statistics for BMD at forearm (n = 10,805), femoral neck (n = 49,988), lumbar spine (n = 44,731) and total-body of different age-stages (< 15, 15-30, 30-45, 45-60, > 60) (n = 67,358). We explored the direct effect of vitamin D on BMD with an adjusted body mass index (BMI) in a multivariable MR analysis. We found no support for causality of 25-hydroxyvitamin D on BMD at forearm, femoral neck, lumbar spine, and total-body BMD across the lifespan. There was no obvious difference between the total and direct effect of vitamin D on BMD after adjusting for BMI. Our MR analysis provided evidence that genetically determined vitamin D was not causally associated with BMD in the general population. Large-scale randomized controlled trials are warranted to investigate the role of vitamin D supplementation in preventing osteoporosis in the high-risk population.

Incidences, causes and risk factors of unplanned reoperations within 30 days of spine surgery: a single-center study based on 35,246 patients.

BACKGROUND CONTEXT: Unplanned reoperation, a quality indicator in spine surgery, has not been sufficiently investigated in a large-scale, single-center study. PURPOSE: To assess the incidences, causes, and risk factors of unplanned reoperations within 30 days of spine surgeries in a single-center study. STUDY DESIGN: Retrospective observational study. PATIENT SAMPLE: A cohort of 35,246 patients who underwent spinal surgery in our hospital were included. OUTCOME MEASURES: The rates, chief reasons, and risk factors for unplanned reoperations within 30 days of spine surgery. METHODS: We retrospectively analyzed the data for patients who underwent spine surgeries for degenerative spinal disorders, tumor, or deformity and had subsequent unplanned operations within 30 days at a single tertiary academic hospital from January 2016 to July 2021. Univariate and multivariate analyses were performed to assess the incidences, causes, and risk factors. RESULTS: Out of 35,246 spinal surgery patients, 297 (0.84%) required unplanned reoperations within 30 days of spine surgery. Patients with a thoracic degenerative disease (3.23%), spinal tumor (1.63%), and spinal deformity (1.50%) had significantly higher rates of reoperation than those with atlantoaxial (0.61%), cervical (0.65%), and lumbar (0.82%) degenerative disease. The common causes for reoperation included epidural hematoma (0.403%), wound infections (0.148%), neurological deficit (0.108%), and pedicle screw malposition (0.077%). Unplanned reoperations were classified as hyperacute (45.45%), acute (30.98%), subacute (15.82%), or chronic (7.74%). Univariate analysis indicated that 20 clinical factors were associated with unplanned reoperation (p<.05). Multivariate Poisson regression analysis revealed that anemia (p<.001), osteoporosis (p=.048), ankylosing spondylitis (p=.008), preoperative foot drop (p=.011), deep venous thrombosis (p<.001), and previous surgical history (p<.001) were independent risk factors for unplanned spinal reoperation. CONCLUSIONS: The incidence of unplanned spinal reoperations was 0.84%. The chief common causes were epidural hematoma, wound infections, neurological deficit, and pedicle screw malposition. Anemia, osteoporosis, ankylosing spondylitis, preoperative foot drop, deep venous thrombosis, and previous surgical history led to an increased risk of unplanned reoperation within 30 days of spine surgery.

Identification of Traditional Chinese Medicine Constitutions and Physiological Indexes Risk Factors in Metabolic Syndrome: A Data Mining Approach.

OBJECTIVE: In order to find the predictive indexes for metabolic syndrome (MS), a data mining method was used to identify significant physiological indexes and traditional Chinese medicine (TCM) constitutions. METHODS: The annual health check-up data including physical examination data; biochemical tests and Constitution in Chinese Medicine Questionnaire (CCMQ) measurement data from 2014 to 2016 were screened according to the inclusion and exclusion criteria. A predictive matrix was established by the longitudinal data of three consecutive years. TreeNet machine learning algorithm was applied to build prediction model to uncover the dependence relationship between physiological indexes, TCM constitutions, and MS. RESULTS: By model testing, the overall accuracy rate for prediction model by TreeNet was 73.23%. Top 12.31% individuals in test group (n=325) that have higher probability of having MS covered 23.68% MS patients, showing 0.92 times more risk of having MS than the general population. Importance of ranked top 15 was listed in descending order . The top 5 variables of great importance in MS prediction were TBIL difference between 2014 and 2015 (D_TBIL), TBIL in 2014 (TBIL 2014), LDL-C difference between 2014 and 2015 (D_LDL-C), CCMQ scores for balanced constitution in 2015 (balanced constitution 2015), and TCH in 2015 (TCH 2015). When D_TBIL was between 0 and 2, TBIL 2014 was between 10 and 15, D_LDL-C was above 19, balanced constitution 2015 was below 60, or TCH 2015 was above 5.7, the incidence of MS was higher. Furthermore, there were interactions between balanced constitution 2015 score and TBIL 2014 or D_LDL-C in MS prediction. CONCLUSION: Balanced constitution, TBIL, LDL-C, and TCH level can act as predictors for MS. The combination of TCM constitution and physiological indexes can give early warning to MS.

Influence of developmental cervical stenosis on dural sac space.

BACKGROUND: This retrospective study aimed to investigate the difference of the intra-dural reserving space for spinal cord in magnetic resonance imaging (MRI) between patients with and without developmental cervical stenosis and its clinical significance. METHODS: A total of 264 patients with cervical spondylotic myelopathy who had decompression surgeries were recruited. The average follow-up was 29 months. Based on their lateral radiographs, they were divided into stenosis group and non-stenosis group. On the magnetic resonance images, the ratio of the sagittal diameter of the dural sac to that of the vertebral body was measured and calculated as MRI Pavlov ratio at the mid-vertebral level on T2-weighted sagittal images from C3 to C7. The ratio of the transverse area of the spinal cord to that of the dural sac was measured and calculated as occupation ratio on T2-weighted axial images at the same levels. The MRI Pavlov ratio and occupation ratio were compared between the two groups. The stenosis group was further divided into space-reserving and non-space-reserving subgroups based on the occupation ratios; then clinical parameters were compared between the two subgroups to determine the clinical significance of the reserving space. RESULTS: The MRI Pavlov ratio of the stenosis group was significantly smaller than that of the non-stenosis group at C3-C7 (P < 0.01), while the occupation ratio was significantly larger only at C7 (P < 0.05). For the space-reserving subgroup, the postoperative recovery rate was lower (P < 0.05). The postoperative recovery rate was (23 ± 6)% in anterior approach, larger than (-23±15)% in posterior approach (P < 0.05). CONCLUSIONS: Developmental cervical stenosis is associated with a smaller sagittal diameter of the dural sac, but does not lead to a significant decrease in intra-dural space available for the cord. For patients with normal intra-dural space, the recovery after anterior decompression surgery was better than posterior approach.