Anti-Stress and Anti-ROS Effects of MnOx-Functionalized Thermosensitive Nanohydrogel Protect BMSCs for Intervertebral Disc Degeneration Repair.

Stem cell transplantation has been proven to be a promising strategy for intervertebral disc degeneration (IDD) repair. However, replicative senescence of bone marrow-derived mesenchymal stem cells (BMSCs), shear damage during direct injection, mechanical stress, and the reactive oxygen species (ROS)-rich microenvironment in degenerative intervertebral discs (IVDs) cause significant cellular damage and limit the therapeutic efficacy. Here, an injectable manganese oxide (MnOx)-functionalized thermosensitive nanohydrogel was proposed for BMSC transplantation for IDD therapy. The MnOx-functionalized thermosensitive nanohydrogel not only successfully protected BMSCs from shear force and mechanical stress before and after injection but also repaired the harsh high-ROS environment in degenerative IVDs, thus effectively increasing the viability of BMSCs and resident nucleus pulposus cells (NPCs). The MnOx-functionalized thermosensitive nanohydrogel provides mechanical protection for stem cells and helps to remove endogenous ROS, providing a promising stem cell delivery platform for the treatment of IDD. This article is protected by copyright. All rights reserved.

Risk Factors for Surgical Treatment of Lumbar Degenerative Disc Disease in Middle-aged and Older Women: A Prospective Case-Control Study of 2370 Subjects.

OBJECTIVE: Given the distinct physiological and societal traits between women and men, we propose that there are distinct risk factors for lumbar degenerative disc disease surgeries, including lumbar disc herniation (LDH) and lumbar spinal stenosis (LSS), in middle-aged and older populations. However, few studies have focused on middle-aged and older women. This study aims to identify these risk factors specifically in this population. METHODS: In this case-control study, the study group comprised 1202 women aged ≥ 45 years who underwent operative treatment of lumbar degenerative disc disease (LDH, n = 825; LSS, n = 377), and the control group comprised 1168 women without lumbar disease who visited a health examination clinic during the same period. The study factors included demographics (age, body mass index [BMI], smoking, labor intensity, and genetic history), female-specific factors (menopausal status, number of deliveries, cesarean section, and simple hysterectomy), surgical history (number of abdominal surgeries, hip joint surgery, knee joint surgery, and thyroidectomy), and systemic diseases (hypercholesterolemia, hypertriglyceridemia, hyper-low-density lipoprotein cholesterolemia, hypertension, diabetes, cardiovascular disease, and cerebrovascular disease). Multivariate binary logistic regression analysis was used to calculate the odds ratio (OR) and 95% confidence interval (95% CI) of associated factors. RESULTS: The risk factors for surgical treatment of LDH in middle-aged and older women included BMI (OR = 1.603), labor intensity (OR = 1.189), genetic history (OR = 2.212), number of deliveries (OR = 1.736), simple hysterectomy (OR = 2.511), hypertriglyceridemia (OR = 1.932), and hyper-low-density lipoprotein cholesterolemia (OR = 2.662). For surgical treatment of LSS, the risk factors were age (OR = 1.889), BMI (OR = 1.671), genetic history (OR = 2.134), number of deliveries (OR = 2.962), simple hysterectomy (OR = 1.968), knee joint surgery (OR = 2.527), hypertriglyceridemia (OR = 1.476), hyper-low-density lipoprotein cholesterolemia (OR = 2.413), and diabetes (OR = 1.643). Cerebrovascular disease was a protective factor against surgery for LDH (OR = 0.267). CONCLUSIONS: BMI, genetic history, number of deliveries, simple hysterectomy, hypertriglyceridemia, and hyper-low-density lipoprotein cholesterolemia were independent risk factors for surgical treatment of both LDH and LSS in middle-aged and older women. Two disparities were found: labor intensity was a risk factor for LDH patients, and knee joint surgery and diabetes were risk factors for LSS patients.

Comparison of Clinical and Radiographic Outcomes Between Transforaminal Endoscopic Lumbar Discectomy and Microdiscectomy: A Follow-up Exceeding 5 Years.

OBJECTIVE: To compare the long-term clinical and radiographic outcomes of transforaminal endoscopic lumbar discectomy (TELD) versus microdiscectomy (MD). METHODS: The data of 154 patients with lumbar disc herniation (LDH) who underwent TELD (n = 89) or MD (n = 65) were retrospectively analyzed. The patients' clinical outcomes were evaluated using visual analogue scales for leg and low back pain, the Japanese Orthopaedic Association (JOA) score, and the Oswestry Disability Index (ODI). The evolution of radiographic manifestations was observed during follow-up. Potential risk factors for a poor clinical outcome were investigated. RESULTS: During a mean follow-up of 5.5 years (range, 5-7 years), the recurrence rate was 4.49% in the TELD group and 1.54% in the MD group. All scores significantly improved from preoperatively to postoperatively in both groups (p < 0.01). The improvement in the ODI and JOA scores was significantly greater in the TELD than MD group (p < 0.05). Forty-seven patients (52.8%) in the TELD group and 32 (49.2%) in the MD group had Modic changes before surgery, most of which showed no changes at the last follow-up. The degeneration grades of 292 discs (71.0%) were unchanged at the last follow-up, while 86 (20.9%) showed improvement, mostly at the upper adjacent segment. No significant difference was observed in the intervertebral height index or paraspinal muscle-disc ratio. CONCLUSION: Both TELD and MD provide generally satisfactory long-term clinical outcomes for patients with LDH. TELD can be used as a reliable alternative to MD with less surgical trauma. Modic type II changes, decreased preoperative intervertebral height, and a high body mass index are predictors of a poor prognosis.

Novel Modic grading scoring system and its clinical validation: a preliminary investigation.

PURPOSE: To propose a novel Modic grading scoring system and explore the relationship between the Modic grading score and disc degeneration, disc herniation, disc height, and clinical symptom scores. METHOD: In total, 194 patients were included in the study. The new Modic grading scoring system included four indicators: invaded vertebral height, invaded endplate length, endplate morphology, and grade of endplate defects. The severity of Modic changes was visually quantified by numerical scores, and the kappa value was used to verify the interobserver and intraobserver reliability. Spearman correlation analysis was used to explore the relationship between the Modic grading score and intervertebral disc degeneration, disc herniation, disc height, and clinical symptom scores. RESULTS: The interobserver and intraobserver reliability showed substantial to almost perfect agreement in the new Modic grading scoring system. The Modic grading score was positively correlated with intervertebral disc degeneration (r = 0.757, p < 0.001) and negatively correlated with the intervertebral disc height index (r = - 0.231, p < 0.001). There was no significant correlation between the Modic grading scoring system and disc herniation (r = 0.369, p = 0.249). Additionally, there was no significant correlation between the Modic grading score and the Japanese Orthopaedic Association score (r = - 0.349, p = 0.25), Oswestry Disability Index score (r = 0.246, p = 0.11), or visual analogue scale score (r = 0.315, p = 0.35). CONCLUSION: The new Modic grading scoring system had good interobserver and intraobserver reliability. The Modic grading score was positively correlated with intervertebral disc degeneration and negatively correlated with the intervertebral disc height.

Effect of Topical Nonsteroidal Anti-inflammatory Drugs Around the Incision on Postoperative Pain in Transforaminal Lumbar Interbody Fusion Surgery: A Double-blind Randomized Controlled Trial.

BACKGROUND: How to minimize postoperative pain following spinal surgery has been a great challenge. We hypothesized that topical nonsteroidal anti-inflammatory drugs (NSAIDs) around the incision could relieve postoperative pain following transforaminal lumbar interbody fusion (TLIF) surgery. OBJECTIVE: This study tested the effect of topical NSAIDs around the incision for pain management after TLIF surgery. STUDY DESIGN: A double-blind randomized controlled trial. SETTING: Qilu Hospital of Shandong University. METHODS: Eighty patients who underwent single-level TLIF surgery were randomized into 2 groups. The treatment group received postoperative topical NSAIDs around the incision. The control group received a postoperative topical placebo around the incision. All patients in both groups received postoperative patient-controlled analgesia (PCA) via an analgesia pump. The primary outcome measures were the amount of opioid consumption and pain measurement via the visual analog scale (VAS). The secondary outcome measures were the time of first analgesic demand, operation time, postoperative drain output, side effects of opioids, postoperative stay, and Oswestry Disability Index (ODI) score. RESULTS: The consumption of opioids in the treatment group was significantly less than in the control group at postoperative 12 hours, 12 to 24 hours, and 24 to 48 hours (P < 0.005). The VAS in the treatment group was significantly lower than those in the control group at all assessment times within 72 hours postoperative (P < 0.005). The time of first analgesic demand of PCA in the treatment group was significantly longer than that in the control group (P < 0.005). The side effects of opioids were significantly less in the treatment group than in the control group (P < 0.05). There was no significant difference in operation time, postoperative drain output, postoperative stay, and ODI between the 2 groups (P > 0.05). LIMITATIONS: This was a single-center study for single-level TLIF surgery. CONCLUSION: Postoperative topical NSAID around the incision is a highly effective and safe method for postoperative pain management following single-level TLIF surgery. In our study it reduced postoperative opioid requirements and prolonged the time of first analgesic demand with no increased side effects. KEY WORDS: Transforaminal lumbar interbody fusion, postoperative pain, NSAID, topical NSAID, nonsteroidal anti-inflammatory drug, loxoprofen.

Safety and accuracy of cannulated pedicle screw placement in scoliosis surgery: a comparison of robotic-navigation, O-arm-based navigation, and freehand techniques.

PURPOSE: To compare the safety and accuracy of cannulated pedicle screw placement using a robotic-navigation technique, O-arm-based navigation technique, or freehand technique. METHODS: This study analyzed 106 consecutive patients who underwent scoliosis surgery. Thirty-two patients underwent robotic-navigation-assisted pedicle screw insertion (Group 1), 34 patients underwent O-arm-based navigation-guided pedicle screw insertion (Group 2), and 40 patients underwent freehand pedicle screw insertion (Group 3). The primary outcome measure was the accuracy of screw placement. Secondary outcome parameters included operation time, blood loss, radiation exposure, and postoperative stay. RESULTS: A total of 2035 cannulated pedicle screws were implanted in 106 patients. The accuracy rate of the first pedicle screw placement during operation was significantly greater in Group 1 (94.7%) than in Group 2 (89.2%; P < 0.001). The accuracy rate of pedicle screw placement postoperatively decreased in the order of Group 1 (96.7%) > Group 2 (93.0%) > Group 3 (80.4%; P < 0.01). There were no significant differences in blood loss or postoperative stay among the three groups (P > 0.05). The operation times of Group 1 and Group 2 were significantly longer than that of Group 3 (P < 0.05). CONCLUSION: The robotic-navigation and O-arm-based navigation techniques effectively increased the accuracy and safety of pedicle screw insertion alternative to the freehand technique in scoliosis surgery. Compared with the O-arm-based navigation technique, the robotic-navigation technique increases the mean operation time, but also increases the accuracy of pedicle screw placement. A three-dimensional scan after insertion of the K-wire may increase the accuracy of pedicle screw placement in the O-arm-based navigation technique.

Comparative study of preoperative sagittal alignment between patients with multisegment cervical ossification of the posterior longitudinal ligament and cervical spondylotic myelopathy.

BACKGROUND CONTEXT: Preoperative sagittal alignment is of great significance in the development of spinal deformities, degenerative diseases, preoperative planning, postoperative clinical evaluation, and functional recovery. However, few reports have focused on the difference in preoperative sagittal alignment between patients with ossification of the posterior longitudinal ligament (OPLL) and patients with cervical spondylotic myelopathy (CSM). PURPOSE: To compare preoperative sagittal alignment between patients with multisegment cervical OPLL and multilevel CSM. STUDY DESIGN: Retrospective study. PATIENT SAMPLE: A total of 243 patients were included in this study. OUTCOME MEASURES: The outcome measures were the Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score, number of hand actions in 10 seconds, hand-grip strength, C2 to C7 Cobb angle, C2 to C5 Cobb angle, C5 to C7 Cobb angle, C2 to C7 sagittal vertical axis, C7 slope, T1 slope, K-line, K-line tilt, and range of motion (ROM). METHODS: The outcome measures were calculated in the OPLL group and CSM group and the data were analyzed using the unpaired t-test, χ² test, and one-way analysis of variance. RESULTS: A total of 243 patients (136 men, 107 women; mean age, 59.1±10.6 years) underwent surgical treatment from September 2013 to December 2021. In total, 123 patients were diagnosed with multisegment cervical OPLL, including continuous type (n=39), segmental type (n=38), and mixed type (n=46). The remaining 120 patients had multisegment CSM. The disease course in the OPLL group was significantly shorter than that in the CSM group (p<.05). Among the above preoperative measurements, the JOA score, number of hand actions in 10 seconds, hand-grip strength, and VAS score were not significantly different between the two groups (p>.05). The C2 to C7 Cobb angle was significantly larger in the OPLL than CSM group (17.7°±9.2° and 14.9°±9.3°, respectively; p< .05), as was the C5 to C7 Cobb angle (10.0°±6.3° and 7.5°±6.1°, respectively; p<.05). The ROM was significantly smaller in the OPLL than CSM group (33.1°±8.1° and 40.1°±10.9°, respectively; p<.001). Within the OPLL group, the ROM was significantly smaller in the continuous type than in the segmental type (p<.05). CONCLUSION: Patients with multisegment cervical OPLL have greater lordotic preoperative sagittal alignment and smaller preoperative ROM than patients with CSM.

How Sagittal Spinal Parameters Predict Anterolateral Spinal Ossification Severity: A Study Based on CT Classification.

STUDY DESIGN: Retrospective observational study. OBJECTIVE: The purpose of this study was to establish a CT classification system of anterolateral spinal ossification and analyze the effects of sagittal spinal parameters on ossification. SUMMARY OF BACKGROUND DATA: Patients with diffuse idiopathic skeletal hyperostosis often present with anterolateral ossification of the spine. Few reports consider anterolateral spinal ossification at each spinal level or explore the influence of sagittal alignment. MATERIALS AND METHOD: One hundred and twenty patients (79 males and 41 females) over 60 years old who underwent whole spinal CT scans from October 2018 to November 2021 were analyzed. Volume rendering technique images were used to assess the degree of anterolateral spinal ossification in each intervertebral space, and a classification system was established. Sagittal parameters, such as thoracic kyphosis, lumbar lordosis (LL), cervical lordosis, sacral slope, and thoracolumbar junction angle of the patients were measured. Multifactor stepwise linear regression analysis and ordered logistic regression analysis were used to study the effects of the sagittal parameters on ossification grades. RESULTS: The median age of the study population was 67 years (63-72 IQR). The new classification system classifies the severity of anterolateral spinal ossification in each intervertebral space into grades 0 to 3 with an intra-observer intraclass correlation coefficient value of 0.909 and inter-observer intraclass correlation coefficient value of 0.900. Multivariate stepwise linear regression analysis showed that age (OR=1.30, P <0.001), weight (OR=1.23, P =0.013), and cervical lordosis (OR=1.19, P <0.001) were significantly correlated with total ossification grade. Multifactor ordered logistic regression analysis showed that there was a statistically significant correlation between cervical lordosis and the ossification grades of each intervertebral space of T1~T4 ( P ≤0.005), between thoracic kyphosis and each intervertebral space in T4~T12 ( P ≤0.019), and between thoracolumbar junction angle and each intervertebral space in T10~L3 ( P ≤0.025). LL was significantly and positively correlated with the ossification grades of each intervertebral space in T7~T11 ( P ≤0.041). LL and sacral slope were significantly negatively correlated with the ossification grades of each intervertebral space in L3~S1 ( P ≤0.047). CONCLUSION: Our new classification scheme demonstrated good accuracy and reliability for the evaluation of the severity of anterolateral spinal ossification. The effect of sagittal parameters on anterolateral spinal ossification was position-specific. The greater the kyphosis or the smaller the lordosis of a spinal region, the more severe the degree of ossification in the corresponding region. LEVEL OF EVIDENCE: 3.

Sacroiliac joint degeneration in degenerative lumbar spondylolisthesis and related risk factors: a retrospective study.

OBJECTIVE: This study was performed to evaluate the degree of radiological sacroiliac joint (SIJ) degeneration in patients with degenerative lumbar spondylolisthesis (DLS). The related risk factors for SIJ degeneration were also investigated. METHODS: We retrospectively analyzed the lumbar and pelvic computed tomography (CT) scans of 303 patients with DLS admitted from January 2018 to December 2021. One hundred and fifty-six age-, gender-, and body mass index-matched patients without lumbar anomality who underwent lower abdominal or pelvic computed tomography scans were included in the control group. Sagittal parameters were measured on full-length lateral radiographs. Two protocols (Backlund's grade and Eno's classification) were used to assess SIJ degeneration. Univariate analysis and bivariate and multivariate regression analysis were performed to identify the factors affecting SIJ degeneration in patients with DLS. RESULTS: According to Backlund's grade and Eno's classification, SIJ degeneration was more severe in the DLS group than in the control group (P < 0.001). Multi-segment degenerative changes (P = 0.032), two-level DLS (P = 0.033), a history of hysterectomy (P < 0.001), lower extremity pain (P = 0.016), and pelvic pain (P = 0.013) were associated with more significant SIJ degeneration as assessed by Backlund's grade. The results of Pearson's correlation analysis showed positive correlation between the sagittal vertical axis and SIJ degeneration (r = 0.232, P = 0.009). The multivariate linear regression analysis showed that a history of hysterectomy was significantly correlated with SIJ degeneration in patients with DLS (r = 1.951, P = 0.008). CONCLUSIONS: SIJ degeneration was more severe in patients with than without DLS. We should take SIJ degeneration into consideration when diagnosing and treating DLS especially those who had undergone previous hysterectomy or showed sagittal malalignment.

Comparison of Clinical Outcomes of Cervical Laminoplasty for Cervical Spondylotic Myelopathy: Double-Door With Lamina Staple, Single-Door With Miniplate, and Double-Door With Spacer-A 2-Year Follow-Up Study.

BACKGROUND: There were few studies to compare the outcomes of different types of cervical laminoplasties. OBJECTIVE: To compare the clinical outcomes of double-door cervical laminoplasty with lamina staple (double-door staple), single-door cervical laminoplasty with miniplate (single-door miniplate), and double-door cervical laminoplasty with spacer (double-door spacer). METHODS: The study involved 166 patients with cervical spondylotic myelopathy (CSM). Fifty-two patients underwent double-door staple, 63 patients underwent single-door miniplate, and 51 patients underwent double-door spacer. The clinical outcomes were measured. RESULTS: There was no significant difference in Japanese Orthopedic Association score among the 3 groups ( P > .05). The operation time was significantly shorter in double-door staple and single-door miniplate groups than in the double-door spacer group ( P < .005). The estimated blood loss was significantly more in the single-door miniplate group than in double-door staple and double-door spacer groups ( P < .005). The expansion ratio of cervical intraspinal cross-sectional area decreased in the order of double-door staple > double-door spacer > single-door miniplate. There were no significant differences in the expansion ratio of dural sac cross-sectional area among the 3 groups. CONCLUSION: Double-door staple, double-door spacer, and single-door miniplate can achieve favorable clinical outcomes for CSM. The blood loss of double-door staple is less than that of single-door miniplate, and the operation time of double-door staple is shorter than that of double-door spacer. The mean expansion ratio of cervical intraspinal cross-sectional area decreased in the order of double-door staple > double-door spacer > single-door miniplate. Overall, double-door staple is a safe and innovative alternative choice for treatment of CSM.

Comparative Study between Caspar Cervical Retractor System and Traditional S Retractor in Application on Anterior Cervical Decompression and Fixation.

OBJECTIVE: Although Caspar cervical retractor system (CCRS) is commonly utilized in anterior cervical decompression and fixation (ACDF), most urban hospitals still use both traditional S retractor and CCRS in conventional anterior cervical surgeries. Related data to evaluate the effect are required to be reported. The aim of this study is to compare the efficacy between using the traditional cervical S retractor and CCRS in anterior cervical decompression and fixation ACDF. METHODS: The retrospective study that total 360 patients received ACDF using different retractors (traditional S retractor or CCRS) were enrolled in this study from January 2010 to January 2020. Width change rate of cervical prevertebral soft tissue, throat symptoms, and subjective experiences of the operating surgeons were evaluated by t-test or analysis of variance (ANOVA) respectively. RESULTS: The width change rate of prevertebral soft tissue was significantly higher in the S retractor group than that of the CCRS group both in single segment group (40.9% vs 20.8%, P < 0.05) and double segments group (45.8% vs 25.2%; p < 0.05). In the three segments group, the width change rate of prevertebral soft tissue was higher in the S retractor group than that of the CCRS group, but with no statistical significance (27.3% vs 23.6%; P > 0.05). The incidence rates of dysphagia, dyspnea, and throat discomfort in the traditional S retractor group were significantly higher compared to the CCRS group (P < 0.05), while satisfactory rate of surgeon was higher in the CCRS group (P < 0.05). However, there was no correlation between anterior soft tissue rate and operative time (P > 0.05), as well as the width change rate of anterior soft tissue and the DNRS score (P > 0.05). CONCLUSION: CCRS was superior compared to the traditional S retractor in reducing the postoperative complications and the postoperative fatigue of surgeon. Meanwhile, the width change rate of prevertebral soft tissue was not related to operative time and DNRS score.

Comparison of robot-assisted versus fluoroscopy-assisted minimally invasive transforaminal lumbar interbody fusion for degenerative lumbar spinal diseases: 2-year follow-up.

This study was performed to prospectively compare the clinical and radiographic outcomes between robot-assisted minimally invasive transforaminal lumbar interbody fusion (RA MIS-TLIF) and fluoroscopy-assisted minimally invasive transforaminal lumbar interbody fusion (FA MIS-TLIF) in patients with degenerative lumbar spinal diseases. One hundred and twenty-three patients with lumbar degenerative diseases (lumbar spinal stenosis with instability and spondylolisthesis [degenerative spondylolisthesis or isthmic spondylolisthesis]) who underwent MIS-TLIF in our hospital were included in this study. Sixty-one patients underwent RA MIS-TLIF (Group A) and 62 patients underwent FA MIS-TLIF (Group B). Group A was further divided into Subgroup AI (46 single-level procedures) and Subgroup AII (15 double-level procedures). Group B was further divided into Subgroup BI (45 single-level procedures) and Subgroup BII (17 double-level procedures). The clinical outcome parameters were the visual analog scale (VAS) score, Oswestry Disability Index (ODI) score, operative time, number of intraoperative fluoroscopies, blood loss, postoperative hospital stay, and postoperative complications. The radiographic change measures were the accuracy of screw placement, facet joint violation (FJV), fusion status, and change in disc height at the proximal adjacent segment at the 2-year follow-up. There were no significant differences in the VAS and ODI scores, blood loss, or postoperative hospital stay between Groups A and B (p > 0.05). The operative time was longer in Group A than B (p = 0.018). The operative time was longer in Subgroup AI than BI (p = 0.001). However, there was no significant difference between Subgroups AII and BII (p > 0.05). There was no significant difference in the number of intraoperative fluoroscopies for patients between Groups A and B (p > 0.05). Although the number of intraoperative fluoroscopies for patients was significantly higher in Subgroup AI than BI (p = 0.019), there was no significant difference between Subgroups AII and BII (p > 0.05). The number of intraoperative fluoroscopies for the surgeon was significantly lower in Group A than B (p < 0.001). For surgeons, the difference in the average number of intraoperative fluoroscopies between Subgroups AI and AII was 2.98, but that between Subgroups BI and BII was 10.73. In Group A, three guide pins exhibited drift and one patient developed a lateral wall violation by a pedicle screw. One pedicle screw perforated the anterior wall of the vertebral body and another caused an inner wall violation in Group B. The rate of a perfect screw position (grade A) was higher in Group A than B (p < 0.001). However, there was no significant difference in the proportion of clinically acceptable screws (grades A and B) between the two groups. The mean FJV grade was significantly higher in Group B than A (p < 0.001). During at 2-year postoperative follow-up, there was no significant difference in the fusion status between the two groups (p > 0.05); however, the decrease in disc height at the proximal adjacent segment was significantly less in Group A than B (p < 0.001). Robot-assisted percutaneous pedicle screw placement is a safer and more accurate alternative to conventional freehand fluoroscopy-assisted percutaneous pedicle screw insertion in MIS-TLIF.

Necessity of routinely performing foraminoplasty during percutaneous endoscopic transforaminal discectomy (PETD) for lumbar disc herniation.

OBJECTIVE: To assess the role of foraminoplasty during percutaneous endoscopic transforaminal discectomy (PETD) and compared the 2-year clinical results of patients underwent PETD w/o foraminoplasty. METHODS: A total of 412 patients, who underwent PETD at L3-S1 by the same surgical group, were enrolled in this study. The MRI was used to determine the height (H1) and width (W1) of the intervertebral foramen of L3-S1, the distance between the exiting nerve root and the upper edge of the lower vertebral pedicle (H2), and the distance (W2) between the point with 3 mm to the ventral side of the intervertebral space and superior articular process. The intervertebral foramen widths in the flexion (W3) and extension positions (W4) were also measured. A VAS of low back pain (LBP) and leg pain, ODI and JOA scores of LBP were used to assess the clinical results. RESULTS: Intraoperative verification showed that 347 cases (group A) did not need foraminoplasty, while the other 65 patients (group B) needed foraminoplasty, including 31 at L4-5 and 34 at L5-S1. The H1 and H2 of L3-S1 were reduced gradually without significant difference between two groups. The W1, W2, W3 and W4 were higher in group A (p < 0.05). The W3 was higher than W4 in both groups (p < 0.05). At 2-year follow-up, there was no significant difference of ODI and JOA score between two groups (p > 0.05). The VAS score of LBP was better in group A (p < 0.05). CONCLUSIONS: Most of PETD procedure at L3-S1 levels could reach the therapeutic target without foraminoplasty. Due to anatomic characteristics of L5-S1, the foraminoplasty rate was much higher at L5-S1.

Posterior Temporary C1-2 Pedicle Screws Fixation for the Treatment of Unstable C1-2 Complex Fractures: Minimum of 2-Year Follow-Up.

STUDY DESIGN: Retrospective. OBJECTIVES: To present rarely reported complex fractures of the upper cervical spine (C1-C2) and discuss the clinical results of the posterior temporary C1-2 pedicle screws fixation for C1-C2 stabilization. METHODS: A total of 19 patients were included in the study (18 males and 1 female). Their age ranged from 23 to 66 years (mean age of 39.6 years). The patients were diagnosed with complex fractures of the atlas and the axis of the upper cervical spine and underwent posterior temporary C1-2 pedicle screws fixation. The patients underwent a serial postoperative clinical examination at approximately 3, 6, 9 months, and annually thereafter. The neck disability index (NDI) and the range of neck rotary motion were used to evaluate the postoperative clinical efficacy of the patients. RESULTS: The average operation time and blood loss were 110 ± 25 min and 50 ± 12 ml, respectively. The mean follow-up was 38 ± 11 months (range 22 to 60 months). The neck rotary motion before removal, immediately after removal, and the last follow-up were 68.7 ± 7.1°, 115.1 ± 11.7°, and 149.3 ± 8.9° (P < 0.01). The NDI scores before and after the operation were 42.7 ± 4.3, 11.1 ± 4.0 (P < 0.01), and the NDI score 2 days after the internal fixation was removed was 7.3 ± 2.9, which was better than immediately after the operation (P < 0.01), and 2 years after the internal fixation was removed. The NDI score was 2.0 ± 0.8, which was significantly better than 2 days after the internal fixation was taken out (P < 0.001). CONCLUSIONS: Posterior temporary screw fixation is a good alternative surgical treatment for unstable C1-C2 complex fractures.

Clinical Validity of 3 Different Grading Systems for Facet Joint Violation: A Retrospective Study and In-Depth Review.

STUDY DESIGN: Retrospective. OBJECTIVES: To study the violation rate of 3 different types of facet joint violation (FJV) grading systems (Babu, Shah, and Park), and to evaluate the accuracy, reliability, and association with clinical outcomes of the above 3 grading systems. METHODS: 152 patients of lumbar spinal stenosis treated with percutaneous pedicle screw placement were enrolled in our study. FJV was evaluated on 3-dimensional lumbar CT reconstruction. Three types of grading systems were used to evaluate FJV: Babu's system (grading by the severity of violation), Shah's system (grading by side of violation), and modified Park's system (grading by different components to cause violation). The violation rate and observer consistency of the 3 grading systems were analyzed. Clinical outcomes were evaluated by visual analog score (VAS), Oswestry disability index (ODI) score. RESULTS: Kappa coefficients of interobserver consistency on Babu, Shah, and Park grading systems were 0.726,0.849,0.692, respectively. The violation rate of Babu, Shah, and Park grading systems were comparable, which were 34.54%, 32.57%, 33.55%, respectively. In all 3 grading systems, the postoperative VAS low-back pain and ODI scores in non-FJV groups were lower than those in FJV groups (P < .05), and there were no significant differences between 2 groups in VAS leg pain(P >.05). CONCLUSIONS: Babu, Shah and modified Park grading system are reliable grading systems, and it reported comparable violation rate. The self-reported clinical outcomes of patients with FJV were worse at 2-year follow-up. For clinical application, it is recommended to use 2 or even 3 different grading systems together to evaluate the FJV.

Neurological Safety of Endoscopic Transforaminal Lumbar Interbody Fusion: A Magnetic Resonance Neurography Study.

OBJECTIVE: A magnetic resonance neurography (MRN) study was conducted to assess the neurological safety of endoscopic transforaminal lumbar intervertebral fusion (endo-TLIF). MATERIALS AND METHODS: A total of 56 healthy volunteers (29 men, 27 women; average age, 44 yr; age range, 21-60 yr) were included in the study. Coronal MRN images were collected from L2/L3 to L5/S1. The working triangle, modified working zone, and safest working zone areas, as well as the vertical and horizontal safe operation diameters, were measured. Linear regression analyses were conducted to explore the correlations between general characteristics (sex, age, height, body mass index) and the measured radiographic indicators. RESULTS: MRN can effectively evaluate the operation zone of endo-TLIF. The safest working zone, modified working zone, and working triangle areas were largest at L4/L5 (92.4±23.4, 136±35.6, and 197±41.7 mm 2 , respectively) and smallest at L2/L3 (45.5±12.9, 68.1±19.5, and 92.6±24.4 mm 2 , respectively). The vertical safe operation diameter was large at L4/L5 and L2/L3 (5.34±0.8 and 5.42±0.9 mm, respectively) and smallest at L5/S1 (2.94±0.9 mm). The horizontal safe operation diameter was large at L4/L5 (7.28±1.2 mm) and smaller at L5/S1 and L2/L3 (4.28±1.0 and 4.77±0.8 mm, respectively). CONCLUSIONS: L4/L5 has the lowest risk of nerve injury, and may be the safest level for beginners initiating endo-TLIF in their practice. We recommend that coronal MRN is routinely performed before endo-TLIF to minimize the risk of neurological injury.

Comparison of the Accuracy of Pedicle Screw Placement Using a Fluoroscopy-Assisted Free-Hand Technique with Robotic-Assisted Navigation Using an O-Arm or 3D C-Arm in Scoliosis Surgery.

STUDY DESIGN: Retrospective. OBJECTIVES: To report and compare the application of robotic-assisted navigation with an O-arm or three-dimensional (3D) C-arm-assisted pedicle screw insertion in scoliosis surgery, and compare with free-hand technique. METHODS: One hundred and forty-four scoliosis patients were included in this study. Ninety-two patients underwent robotic-assisted pedicle screw insertion (Group A), and 52 patients underwent freehand fluoroscopy-guided pedicle screw insertion (Group B). Group A was further divided into Subgroup AI (n = 48; robotic-assisted navigation with an O-arm) and Subgroup AII (n = 44; robotic-assisted navigation with a 3D C-arm). The evaluated clinical outcomes were operation time, blood loss, radiation exposure, postoperative hospital stay, and postoperative complications. The clinical outcomes, coronal and sagittal scoliosis parameters and the accuracy of the pedicle screw placement were assessed. RESULTS: There were no significant differences in blood loss and postoperative hospital stay between Groups A and B (P = .406, P = .138, respectively). Radiation exposure for patients in Group A (Subgroups AI or AII) was higher than that in Group B (P < .005), and Subgroup AI had higher patient radiation exposure compared with Subgroup AII (P < .005). The operation time in Subgroup AII was significantly longer than that in Subgroup AI and Group B (P = .016, P = .032, respectively). The proportion of clinically acceptable screws was higher in Group A (Subgroups AI or AII) compared with Group B (P < .005). CONCLUSIONS: Robotic-assisted navigation with an O-arm or 3D C-arm effectively increased the accuracy and safety in scoliosis surgery. Compared with robotic-assisted navigation with a 3D C-arm, robotic-assisted navigation with an O-arm was more efficient intraoperatively.

SIRT2 promotes the viability, invasion and metastasis of osteosarcoma cells by inhibiting the degradation of Snail.

Osteosarcomas (OS) are highly metastatic and usually lead to poor outcomes. Epithelial-mesenchymal transition (EMT) is reported to be a critical event in metastasis. SIRT2 exerts dual functions in many different tumors. However, the underlying molecular mechanisms of SIRT2 in osteosarcoma cell metastasis and the question of whether SIRT2 regulates EMT have not been fully explored. In this study, we confirmed that SIRT2 was highly-expressed in human osteosarcoma MG63 and Saos-2 cell lines. The viability, migration and invasion of osteosarcoma cells were inhibited by knockdown of SIRT2 and were enhanced by overexpression of SIRT2. Moreover, SIRT2 positively regulated EMT and upregulated the protein levels of the mesenchymal markers N-cadherin and Vimentin and the levels of MMP2 and MMP9. A xenograft mouse model showed that SIRT2 knockdown in osteosarcoma cells led to reduced tumor growth, decreased expression of mesenchymal markers and impaired lung and liver metastasis in vivo. Furthermore, we showed that SIRT2 interacted with and upregulated the protein level of the EMT-associated transcription factor Snail. SIRT2 inhibited Snail degradation via its deacetylase activity. Knockdown of Snail abrogated the promoting effects of SIRT2 on migration and invasion of osteosarcoma cells. In conclusion, SIRT2 plays a crucial role in osteosarcoma metastasis by inhibiting Snail degradation and may serve as a novel therapeutic target to manage osteosarcoma.

Age-related radiographic parameters difference between the degenerative lumbar spinal stenosis patients and healthy people and correlation analysis.

OBJECTIVES: To identify age-related radiographic risk factors for degenerative lumbar spinal stenosis (DLSS) and analyze correlations among them. METHODS: A total of 180 cases were enrolled in this study, and lumbar magnetic resonance was performed. Among them, 93 cases suffered DLSS and lumbar dynamic X-ray was examined. And following parameters were measured and evaluated: intervertebral disk height (IDH), the ratio of IDH(IDHL4-5/L3-4), initial IDH of L4-5(iIDHL4-5) in the DLSS group, disk degeneration (DD), cartilaginous endplate failure (CEF), Modic changes, the thickness of ligamentum flavum (LF), range of intervertebral motion (ROM), facet joint opening (FJO), facet joint angle (FJA), the standard cross-sectional area (SCSA) of the multifidus, erector spinae, and psoas major muscles. The data of two groups were compared, and the possible risk factors of DLSS were analyzed. RESULTS: Compared with the control group, the DLSS group had higher IDH except for L4-5 and larger iIDHL4-5 (P < 0.05). Significant differences were shown in CEF and the thickness of LF at L1-S1 and DD at L4-5 (P < 0.05). The DLSS group had smaller SCSA of multifidus, erector spinae, and psoas major muscles but greater FJA, FJO (P < 0.05). And the risk of DLSS increased when iIDHL4-5 ≥ 10.73 mm, FJA ≥ 52.03° , or FJO ≥ 3.75 mm. IDH positively correlated with SCSA of multifidus and psoas major muscles and ROM at L1-S1 (P < 0.05). DD showed negative linear relations with SCSA of multifidus and psoas muscle and positive linear relation with CEF at L1-2, L2-3, and L5-S1 (P < 0.05). CONCLUSION: Larger initial disk height and excessive CEF may induce DLSS by increasing intervertebral mobility to promote DD, and atrophied paravertebral muscles by weakening the stability of lumbar spine.

Radiological Changes of Paraspinal Muscles: A Comparative Study of Patients with Isthmic Spondylolisthesis, Patients with Degenerative Lumbar Spondylolisthesis, and Healthy Subjects.

Objective: To investigate the differences, correlations, and clinical significance of the paraspinal muscles among patients with isthmic spondylolisthesis (IS), degenerative lumbar spondylolisthesis (DLS), and age-matched healthy subjects. Methods: This study involved 159 age-matched patients with L4 anterior spondylolisthesis. The patients were divided into the IS group (n = 81) and DLS group (n = 78). Eighty-four age-matched healthy adults were enrolled as the control group. The cross-sectional area (CSA) of paraspinal muscles (multifidus [MF], erector spinae [ES], and psoas [PS]) and the relative CSA of the paraspinal muscles (paraspinal muscle CSA/vertebral CSA) were measured in the IS group, DLS group, and control group. The degree of fat infiltration was simultaneously observed. Results: There was no significant difference in age or sex among the three groups. The relative CSA of the MF and PS was higher in control group than in IS and DLS groups (p < 0.05). The relative CSA of ES was higher in IS and control groups than in DLS group (p < 0.05). The relative CSA of total paraspinal muscles decreased in the order of control group > IS group > DLS group (p < 0.05). Logistic regression analysis showed that the relative CSA of MF, and the degree of fat infiltration of ES were independent protective factors for IS (odds ratio < 1, p < 0.05). The relative CSA of MF was an independent protective factor for DLS (odds ratio < 1, p < 0.05), whereas BMI and the degree of fat infiltration of MF were independent risk factor for DLS (odds ratio > 1, p < 0.05). Conclusion: Compared with the control group, patients with IS and DLS showed varying degrees of degeneration, and the degree of degeneration in patients with DLS was more severe at the same age. Lower fat infiltration and higher paraspinal muscle CSA are protective factors for IS and DLS, whereas the higher BMI is risk factor for DLS.