Comparison of infant bone marrow- and umbilical cord-derived mesenchymal stem cells in multilineage differentiation.

We compared infant bone marrow-derived mesenchymal stem cells (infant BMSCs) with umbilical cord-derived mesenchymal stem cells (UCSCs) by assessing multilineage differentiation. Proliferation was gauged through changes in cell numbers and doubling time. Senescence-related genes (p16, p21, and p53), senescence-associated ß-galactosidase (SA-ß-gal), and γH2AX immunofluorescence determined senescence presence. Superoxide dismutases (SODs) and genes related to various differentiations were analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Differentiation was confirmed through histochemical, immunohistochemical, and immunofluorescence staining. Infant BMSCs surpassed UCSCs in proliferation. Infant BMSCs exhibited lower senescence-related gene expression at late passages, upregulated antioxidant enzymes during early passages, and reduced SA-ß-gal staining. Chondrogenic gene expression (SOX9, COL2, and COL10) was enhanced in infant BMSCs, along with improved immunohistochemical staining. Infant BMSCs showed higher expression of osteogenic (ALP and OCN) and adipogenic (PPARγ and LPL) genes, confirmed by histochemical staining. However, UCSCs had higher expression of tenogenic genes (MMP3, SCX, DCN, and TNC). Hepatogenic differentiation potential was similar, with no significant difference in hepatogenic gene expression (ALB and TAT). Compared to UCSCs, infant BMSCs demonstrated superior proliferation, reduced senescence, increased antioxidant capacity, and enhanced differentiation potential toward chondrogenic, osteogenic, and adipogenic lineages.

Development and validation of deep learning models for identifying the brand of pedicle screws on plain spine radiographs.

Background: In spinal revision surgery, previous pedicle screws (PS) may need to be replaced with new implants. Failure to accurately identify the brand of PS-based instrumentation preoperatively may increase the risk of perioperative complications. This study aimed to develop and validate an optimal deep learning (DL) model to identify the brand of PS-based instrumentation on plain radiographs of spine (PRS) using anteroposterior (AP) and lateral images. Methods: A total of 529 patients who received PS-based instrumentation from seven manufacturers were enrolled in this retrospective study. The postoperative PRS were gathered as ground truths. The training, validation, and testing datasets contained 338, 85, and 106 patients, respectively. YOLOv5 was used to crop out the screws' trajectory, and the EfficientNet-b0 model was used to develop single models (AP, Lateral, Merge, and Concatenated) based on the different PRS images. The ensemble models were different combinations of the single models. Primary outcomes were the models' performance in accuracy, sensitivity, precision, F1-score, kappa value, and area under the curve (AUC). Secondary outcomes were the relative performance of models versus human readers and external validation of the DL models. Results: The Lateral model had the most stable performance among single models. The discriminative performance was improved by the ensemble method. The AP + Lateral ensemble model had the most stable performance, with an accuracy of 0.9434, F1 score of 0.9388, and AUC of 0.9834. The performance of the ensemble models was comparable to that of experienced orthopedic surgeons and superior to that of inexperienced orthopedic surgeons. External validation revealed that the Lat + Concat ensemble model had the best accuracy (0.9412). Conclusion: The DL models demonstrated stable performance in identifying the brand of PS-based instrumentation based on AP and/or lateral images of PRS, which may assist orthopedic spine surgeons in preoperative revision planning in clinical practice.

Erector spinae plane block level does not impact analgesic efficacy in enhanced recovery for lumbar spine surgery.

BACKGROUND CONTEXT: Postoperative pain control following spine surgery can be difficult. The Enhanced Recovery After Surgery (ERAS) programs use multimodal approaches to manage postoperative pain. While an erector spinae plane block (ESPB) is commonly utilized, the ideal distance for injection from the incision, referred to as the ES (ESPB to mid-surgical level) distance, remains undetermined. PURPOSE: We evaluated the impact of varying ES distances for ESPB on Numerical Rating Scale (NRS) measures of postoperative pain within the ERAS protocol. STUDY DESIGN/SETTING: Retrospective observational study. PATIENT SAMPLE: Adult patients who underwent elective lumbar spine fusion surgery. OUTCOME MEASURES: Primary outcome measures include the comparative postoperative NRS scores across groups at immediate (T1), 24 (T2), 48 (T3), and 72 (T4) hours postsurgery. For secondary outcomes, a propensity matching analysis compared these outcomes between the ERAS and non-ERAS groups, with opioid-related recovery metrics also assessed. METHODS: All included patients were assigned to one of three ERAS groups according to the ES distance: Group 1 (G1, ES > 3 segments), Group 2 (G2, ES = 2-3 segments), and Group 3 (G3, ES<2 segments). Each patient underwent a bilateral ultrasound-guided ESPB with 60 mL of diluted ropivacaine or bupivacaine. RESULTS: Patients within the ERAS cohort reported mild pain (NRS < 3), with no significant NRS variation across G1 to G3 at any time. Sixty-five patients were matched across ERAS and non-ERAS groups. The ERAS group exhibited significantly lower NRS scores from T1 to T3 than the non-ERAS group. Total morphine consumption during hospitalization was 26.7 mg for ERAS and 41.5 mg for non-ERAS patients. The ERAS group resumed water and food intake sooner and had less postoperative nausea and vomiting. CONCLUSIONS: ESPBs can be effectively administered at or near the mid-surgical level to the low thoracic region for lumbar spine surgeries. Given challenges with sonovisualization, a lumbar ESPB may be preferred to minimize the risk of inadvertent pleural injury.

MRI-based lesion quality score assessing ossification of the posterior longitudinal ligament of the cervical spine.

BACKGROUND CONTEXT: No method currently exists for MRI-based determination of ossification of the posterior longitudinal ligament (OPLL) of the cervical spine using objective criteria. PURPOSE: The purpose of this study was to develop an MRI-based score to determine whether a lesion represents a cervical OPLL lesion and to establish the objective diagnostic value. STUDY DESIGN: Retrospective cohort in a single medical institution. PATIENT SAMPLE: Thirty-five patients undergoing surgery for OPLL (Group A) and 99 patients undergoing cervical disc arthroplasty for soft disc herniation (Group B) between 2011 and 2020 were retrospectively included. All OPLL lesions on unenhanced MRI scan were correlated with a corresponding CT scan. Demographics were comparable between the two groups. OUTCOME MEASURES (PHYSIOLOGIC MEASURES): Using unenhanced magnetic resonance imaging (MRI), the T1- and T2- lesion quality (LQ) scores were calculated. Receiver operating characteristic (ROC) analysis was performed to calculate the area-under-the-curve (AUC) of both LQ scores as a predictor of the presence of OPLL. Computed tomography (CT)-based Hounsfield unit (HU) values of OPLL lesions were obtained and compared with both LQ scores. The LQ scores for MRI scanners from different manufacturers were compared using Student's t test to confirm the validity of the LQ score by scanner type. METHODS: The regions of interest for signal intensity (SI) were defined as the darkest site of the lesion and the cerebrospinal fluid (CSF) at the cerebellomedullary cistern. The T1 and T2 LQ scores were measured as the ratio of the SI at the darkest site of the lesion divided by the SI of the CSF. RESULTS: The T1 and T2 LQ scores in Group A were significantly lower than those in Group B (p<.001). ROC analysis determined that T1 and T2 LQ scores of 0.46 and 0.07, respectively, could distinguish the presence of OPLL with an accuracy of 0.93 and 0.89, respectively (p<.001). When the T1 LQ score of the lesion is <0.46, a diagnosis of OPLL may be suspected with 100% sensitivity and 92.3% specificity. The HU of the lesion had a moderate negative correlation with the T1 LQ score (r=-0.665, p<.0001). Both LQ scores were unaffected by manufacturer type. CONCLUSIONS: This study found a correlation between the MRI-based T1 LQ scores and CT-based HU value for identifying OPLL lesions. Additional studies will be needed to validate that the T1 LQ score from the unenhanced MRI scan can identify cervical OPLL.

Proliferation and Differentiation Potential of Bone Marrow-Derived Mesenchymal Stem Cells From Children With Polydactyly and Adults With Basal Joint Arthritis.

This study compared the proliferation and differentiation potential of bone marrow-derived mesenchymal stem cells (BMSCs) derived from infants with polydactyly and adults with basal joint arthritis. The proliferation rate of adult and infant BMSCs was determined by the cell number changes and doubling times. The γH2AX immunofluorescence staining, age-related gene expression, senescence-associated ß-galactosidase (SA-ß-gal) staining were analyzed to determine the senescence state of adult and infant BMSCs. The expression levels of superoxide dismutases (SODs) and genes associated with various types of differentiation were measured using Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR). Differentiation levels were evaluated through histochemical and immunohistochemical staining. The results showed that infant BMSCs had a significantly higher increase in cell numbers and faster doubling times compared with adult BMSCs. Infant BMSCs at late stages exhibited reduced γH2AX expression and SA-ß-gal staining, indicating lower levels of senescence. The expression levels of senescence-related genes (p16, p21, and p53) in infant BMSCs were also lower than in adult BMSCs. In addition, infant BMSCs demonstrated higher antioxidative ability with elevated expression of SOD1, SOD2, and SOD3 compared with adult BMSCs. In terms of differentiation potential, infant BMSCs outperformed adult BMSCs in chondrogenesis, as indicated by higher expression levels of chondrogenic genes (SOX9, COL2, and COL10) and positive immunohistochemical staining. Moreover, differentiated cells derived from infant BMSCs exhibited significantly higher expression levels of osteogenic, tenogenic, hepatogenic, and neurogenic genes compared with those derived from adult BMSCs. Histochemical and immunofluorescence staining confirmed these findings. However, adult BMSCs showed lower adipogenic differentiation potential compared with infant BMSCs. Overall, infant BMSCs demonstrated superior characteristics, including higher proliferation rates, enhanced antioxidative activity, and greater differentiation potential into various lineages. They also exhibited reduced cellular senescence. These findings, within the context of cellular differentiation, suggest potential implications for the use of allogeneic BMSC transplantation, emphasizing the need for further in vivo investigation.

Differences in productivity and collaboration patterns on spine-related research between neurosurgeons and orthopedic spine surgeons: Bibliometric analysis.

BACKGROUND: Spinal surgeries are commonly performed by neurosurgeons and orthopedic spine surgeons, with many spine-related articles published by them. However, there has been limited research that directly compares their research achievements. This article conducted a comparative analysis of spine-related research achievements between neurosurgeons and orthopedic spine surgeons. This study examines differences in productivity and impact on spine-related research between them using these measures, particularly with a novel clustering algorithm. METHODS: We gathered 2148 articles written by neurosurgeons and orthopedic spine surgeons from the Web of Science core collections, covering the period from 2013 to 2022. To analyze author collaborations, we employed the follower-leader clustering algorithm (FLCA) and conducted cluster analysis. A 3-part analysis was carried out: cluster analysis of author collaborations; mean citation analysis; and a category, journal, authorship, L-index (CJAL) score based on article category, journal impact factors, authorships, and L-indices. We then utilized R to create visual displays of our findings, including circle bar charts, heatmaps with dendrograms, 4-quadrant radar plots, and forest plots. The mean citations and CJAL scores were compared between neurosurgeons and orthopedic spine surgeons. RESULTS: When considering first and corresponding authors, orthopedics authors wrote a greater proportion of the articles in the article collections, accounting for 75% (1600 out of 2148). The CJAL score based on the top 10 units each also favored orthopedic spine surgeons, with 71% (3626 out of 6139) of the total score attributed to them. Using the FLCA, we observed that orthopedic spine surgeons tended to have more collaborations across countries. Additionally, while citation per article favored orthopedic spine surgeons with standard mean difference (= -0.66) and 95%CI: -0.76, -0.56, the mean CJAL score in difference (= 0.34) favored neurosurgeons with 95%CI: 0.24 0.44. CONCLUSION: Orthopedic spine surgeons have a higher number of publications, citations, and CJAL scores in spine research than those in neurosurgeons. Orthopedic spine surgeons tend to have more collaborations and coauthored papers in the field. The study highlights the differences in research productivity and collaboration patterns between the 2 authors in spine research and sheds light on potential contributing factors. The study recommends the use of FLCA for future bibliographical studies.

Preoperative planning of compact zone trajectory is necessary in treating osteoporotic vertebral compression fracture with endplate involvement: A prospective randomized controlled study.

BACKGROUND: This prospective randomized controlled study compares the clinical and radiological outcomes between reduction methods with or without compact trabecular bone during percutaneous kyphoplasty in osteoporotic vertebral fractures. METHODS: The cohort of 100 patients who underwent percutaneous kyphoplasty was randomly divided into group A (guide pin and balloon introduced directly into fracture site) and group B (guide pin and balloon inserted away fracture site). The surgery duration, clinical and radiological outcomes postoperatively and at follow-up, and complications of cement leakage and adjacent fracture were recorded. Patients were followed up for an average of 20.18 months. The clinical outcomes were assessed using the Oswestry Disability Index and visual analog scale. RESULTS: The two groups had similar patient demographics, surgery times, and volume of cement injected. The method using elevation of the collapsed endplate indirectly had no significant influence on radiological outcomes but significantly decreased the occurrence of intradiscal cement leakage and improved 1- and 12-month postoperative functional outcomes. CONCLUSION: Elevating and reinforcing the collapsed endplate rather than just filling the defect during percutaneous kyphoplasty is safe and effective. This technique decreased pain and improved function with lower rates of further collapse of the osteoporotic vertebrae compared to defect-filling alone.

Multilineage differentiation potential in the infant adipose- and umbilical cord-derived mesenchymal stem cells.

BACKGROUND: This study aims to compare the biological properties of infant adipose-derived mesenchymal stem cells (infant ADSCs) from excised polydactyly fat tissue and umbilical cord-derived mesenchymal stem cells (UCSCs) in terms of proliferation and differentiation capabilities. The proliferation of infant ADSCs and UCSCs was analyzed by determining the fold changes of cell numbers and doubling time periods. METHODS: The state of senescence and replicative stress was compared by analyzing the expression of age-related genes, senescence-associated ß-galactosidase (SA-ß-gal) staining, and phosphorylated histone variant H2AX (γH2AX) immunofluorescence staining. The expression levels of superoxide dismutase ( SODs ) and genes related to multilineage differentiation were analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Differentiation levels were determined using histochemical staining, immunohistochemical staining, and immunofluorescence staining. RESULTS: Infant ADSCs exhibited higher proliferation rates and expression levels of SOD1 , SOD2 , and SOD3 at passages 3-5 compared with UCSCs. Senescence related genes ( p16 , p21 , and p53 ), SA-ß-gal staining, and replicative stress analysis were reduced in infant ADSCs. The expression levels of chondrogenic genes ( COL2 and COL10 ), osteogenic genes ( RUNX2 and ALP ), adipogenic genes ( LPL ), and hepatogenic genes ( ALB and TAT ) in infant ADSC-differentiated cells were significantly higher than those in UCSCs. Histochemical and immunofluorescence staining confirmed these results. Only the expression levels of tenogenic genes ( MMP3 , DCN , and COL3 ) in infant ADSC-differentiated cells were lower than those in UCSCs. CONCLUSION: Infant ADSCs exhibit higher proliferation rates, reduced cellular senescence and replicative stress, better antioxidative activity, and higher differentiation potential toward chondrogenic, osteogenic, adipogenic and hepatogenic lineages than UCSCs.

Reducing surgical site infections after spine surgery: the optimal amount of normal saline for intra-wound irrigation.

BACKGROUND CONTEXT: Surgical site infection (SSI) following lumbar surgery can increase healthcare costs and lead to poor clinical outcome. Irrigation of wounds with saline solution is widely accepted globally and safe for nearly all kinds of surgery. However, the efficacy of different volumes of wound irrigation has not been addressed in elective spine surgery. The role and the optimal amount of intraoperative wound saline irrigation in preventing SSI in clean spinal surgery remain unclear. PURPOSE: We aimed to investigate if insufficient intraoperative irrigation may be a risk factor for postoperative SSI. Additionally, we investigated the optimal amount of normal saline (NS) for irrigation to prevent postoperative SSI. STUDY DESIGN: This is a retrospective study of patients with degenerative spinal stenosis who were treated surgically. Patients were grouped according to the amount of intra-wound irrigation during surgery. PATIENT SAMPLE: We included 444 patients with degenerative lumbar spinal conditions who had undergone one to five level open spinal fusion surgeries from January 2015 through April 2020. OUTCOME MEASURES: The definition of superficial or deep SSI in this study was based on the Centers for Disease Control and Prevention criteria for SSI. The fusion status accessed was based on the Bridwell grading system at the final follow-up. Self-reported and clinical outcome measures include visual analog scale and Oswestry Disability Index. METHODS: A total of 193 patients underwent irrigation with a bulb syringe with manual method (B group) with 2,000 mL NS; 251 patients underwent interpulse battery-powered device irrigation (P group) with >6,000 mL NS. Based on our protocolized departmental guidelines, all patients received the same preoperative preparation and standard surgical steps and postoperative care plan. Patients' demographic and surgical parameters were recorded. The main outcome measures included superficial wound infection, deep infection and overall infection. RESULTS: The incidence of overall SSI was 4.66% in the B group and 1.59% in the P group. The univariate analysis revealed a significant correlation with DM and irrigation amount per hour during surgery but not age, BMI, smoking, operative duration, fusion level, or blood loss. We determined the optimal irrigation amount during surgery as 1,400 mL per hour based on the receiver operating characteristic (ROC) curve (sensitivity, 92.3%; specificity, 44.1%). This was statistically significant (p=.033) with an odds ratio of 9.284 (95% confidence interval 1.2-72.0). In the analysis of surgical factors, the infection group had a significantly lower irrigation amount during surgery. To summarize, patients with diabetes and those receiving less than 1,400 mL of NS/hour had a higher likelihood of developing SSI. CONCLUSIONS: We observed that diabetes and lower volume of intraoperative irrigation were both risk factors for postoperative SSI following degenerative lumbar spine surgery. To reduce SSI in lumbar spine surgery, intra-wound irrigation with more than 1,400 mL/h of NS was recommended.

Biomechanical Effects of a Novel Pedicle Screw W-Type Rod Fixation for Lumbar Spondylolysis: A Finite Element Analysis.

Lumbar spondylolysis involves anatomical defects of the pars interarticularis, which causes instability during motion. The instability can be addressed through instrumentation with posterolateral fusion (PLF). We developed a novel pedicle screw W-type rod fixation system and evaluated its biomechanical effects in comparison with PLF and Dynesys stabilization for lumbar spondylolysis via finite element (FE) analysis. A validated lumbar spine model was built using ANSYS 14.5 software. Five FE models were established simulating the intact L1-L5 lumbar spine (INT), bilateral pars defect (Bipars), bilateral pars defect with PLF (Bipars_PLF), Dynesys stabilization (Bipars_Dyn), and W-type rod fixation (Bipars_Wtyp). The range of motion (ROM) of the affected segment, the disc stress (DS), and the facet contact force (FCF) of the cranial segment were compared. In the Bipars model, ROM increased in extension and rotation. Compared with the INT model, Bipars_PLF and Bipars_Dyn exhibited remarkably lower ROMs for the affected segment and imposed greater DS and FCF in the cranial segment. Bipars_Wtyp preserved more ROM and generated lower stress at the cranial segment than Bipars_PLF or Bipars_Dyn. The injury model indicates that this novel pedicle screw W-type rod for spondylolysis fixation could return ROM, DS, and FCF to levels similar to preinjury.

The Impact of Cage and End plate-Related Factors on Cage Subsidence in Oblique Lateral Interbody Fusion.

OBJECTIVES: To identify cage and end plate factors of cage subsidence (CS) in patients who underwent oblique lateral interbody fusion (OLIF) and their association with patient-reported outcomes. METHODS: Sixty-one patients (43 women and 18 men), with a total of 69 segments (138 end plates) which underwent OLIF at a single academic institution between November 2018 and November 2020, were included. All the end plates were separated into CS and nonsubsidence groups. Cage-related parameters (cage height, cage width, cage insertion level, and cage position) and end plate-related parameters (position of end plate, Hounsfield unit value of the vertebra, end plate concave angle [ECA], end plate injury, and angular mismatch measured with cage/end plate angle [C/EA]) were compared and analyzed using logistic regression to predict CS. Receiver operating characteristic curve analysis was used to determine the cutoff points of the parameters. RESULTS: Postoperative CS was identified in 50 of the 138 end plates (36.2%). The CS group had significantly lower mean Hounsfield unit values of the vertebra, higher rate of end plate injury, lower ECA, and higher C/EA than the nonsubsidence group. ECA and C/EA were identified as independent risk factors for developing CS. The optimal cutoff points for ECA and C/EA were 176.9° and 5.4°, respectively. CONCLUSIONS: An ECA greater than 176.9° and a cage/end plate angular mismatch greater than 5.4° were found to be independent risk factors of postoperative CS after the OLIF procedure. These findings aid in preoperative decision-making and intraoperative technical guidance.

Shorter screw lengths in dynamic Dynesys fixation have less screw loosening: From clinical investigation to finite-element analysis.

BACKGROUND: The dynamic Dynesys Stabilization System preserves lumbar mobility at instrumented levels. This study investigated the effect of screw length on screw loosening (SL) after dynamic Dynesys fixation and screw displacement during lumbar motion, using clinical investigation and finite-element (FE) analysis. METHODS: Clinical data of 50 patients with degenerative spondylolisthesis treated with decompression and Dynesys fixation in 2011 were analyzed retrospectively. Horizontal sliding displacement and vertical displacement of screw tips at L4 were analyzed postoperatively using displacement-controlled FE analysis at the L4-L5 level with screw lengths 45 (long screw), 36 (median screw), and 27 (short screw), and 6.4 mm in diameter, under flexion, extension, lateral bending, and rotation. RESULTS: In 13 patients (13/50, 26%), 40 screws (40/266, 15%) were loose at mean follow-up of 101.3 ± 4.4 months. Radiographic SL at 35, 40, 45, and 50 mm were 7.7%, 10.7%, 12.1%, and 37.5%, respectively, regardless of the fixation level ( p = 0.009). FE analysis revealed that the long screw model with corresponding longer lever arm had maximal horizontal sliding displacement under all directions and maximal vertical displacement, except for lateral bending. CONCLUSION: Shorter screws in Dynesys fixation may help avoid dynamic SL. Clinically, 50 mm screws showed the greatest SL and median screw screws demonstrated the least displacement biomechanically.

Investigation of preoperative asymptomatic bacteriuria as a risk factor for postvertebroplasty infection.

BACKGROUND: Postvertebroplasty infection (PVI) is a catastrophic complication after vertebroplasty (VP). Although the urinary tract has been considered as a source of infectious pathogens, whether asymptomatic bacteriuria (ASB) is a risk factors for PVI remains unknown. METHODS: This retrospective study included 716 patients (207 males; 509 females) treated with VP for osteoporotic vertebral fractures in a single medical center between May 2015 and December 2019. Clinical symptoms, urinalysis results, and culture data were collected preoperatively to identify patients with ASB. The primary outcome was PVI at the index level during follow-up. Demographic data and laboratory test results were compared between the PVI and non-PVI groups. RESULTS: The mean age of the cohort was 78.6 ± 9.6 (range, 63-106). The prevalence of ASB was 14.1%, with female predominance (63.4%). The overall PVI rate was 1.26% (9/716). The PVI group had more patients with ASB (4/9, 44.4%) than did the non-PVI group (97/707, 13.7%) (p = 0.027). The rate of ASB treatment was similar between the PVI and non-PVI groups (25% vs. 23.7%, respectively). No case of PVI was caused by the urine culture pathogen. Multivariate analysis identified the following risk factors for PVI: ASB (odds ratio [OR], 5.61; 95% CI, 1.14-27.66; p = 0.034), smoking (OR, 16.26; 95% CI, 2.58-102.65; p = 0.003), and malignancy (OR 7.27; 95% CI, 1.31-40.31; p = 0.023). CONCLUSION: ASB was not uncommon among patients admitted for VP and should be considered a marker of relatively poor host immunity. Preoperative ASB, a history of malignancy, and smoking were identified as significant risk factors for PVI.

CT Hounsfield unit is a reliable parameter for screws loosening or cages subsidence in minimally invasive transforaminal lumbar interbody fusion.

Retrospective cohort study. To validate computed tomography (CT) radiodensity in Hounsfield units (HU) as a prognostic marker for pedicle screw loosening or cage subsidence in minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). The retrospective study involved 198 patients treated with MI-TLIF. Screw loosening (SL), cage subsidence (CS), and fusion status were assessed by plain radiographs. The risk factors of SL and CS were identified using logistic regression. A total of 258 levels and 930 screws were analyzed. During a 2-year follow-up, 16.2% and 24.7% of patients had CS and SL respectively. The cut-off value of L1 HU for predicting SL or CS was 117. The L1 HU < 117 and BMI ≥ 25 were two independent risk factors. The risk of SL or CS was 4.1 fold in patients L1 HU < 117 and 2.6 fold in patients with BMI ≥ 25. For patients concurrently having BMI ≥ 25 and pre-op L1 HU < 117, the risk was 4.3 fold. Fusion rate and clinical outcome were comparable in patients with SL or CS. L1 HU < 117 and BMI > 25 were two independent risk factors that can be screened preoperatively for preventing SL or CS and lead to better management of patients undergoing MI-TLIF.

Posterior instrumentation for osteoporotic fractures in the thoracic or lumbar spine: Cement-augmented pedicle screws vs hybrid constructs.

BACKGROUND: Cement-augmented pedicle screws (CPS) and hybrid construct (HC), consisting of pedicle screws and additional hooks, are common fixation methods for osteoporotic spine fracture. No study has compared surgical results of CPS and HC for treating osteoporotic spine fracture. The aim of the study was to compare surgical results using CPS or HC for osteoporotic fractures of the thoracic or lumbar spine. METHODS: This retrospective cohort study included 84 patients who received surgical treatment with CPS (n = 43) or HC (n = 41) for osteoporotic spine fractures from January 2011 to December 2015, with a mean follow-up of 67 months. Sixty-five patients with neurological deficits received long posterior instrumentation, short posterior decompression, and posterolateral fusion. The 19 patients without neurologic deficits received long posterior instrumentation without posterior decompression and fusion. Radiographic, clinical, and neurologic outcomes were evaluated. RESULTS: The HC group had significantly shorter operative times (231 vs 258 minutes), greater blood loss (497 vs 427 mL), better immediate postoperative kyphosis reduction (10.6° vs 9.1°), and greater final reduction loss (9.8° vs 7.1°) than the CPS group. In both groups, significant loss of the kyphotic angle was apparent during follow-up. Improved ambulation after surgery occurred in 51.2% and 58.5% of patients in the CPS and HC groups, respectively. Neurologic function after surgery improved 0.5 and 0.7 grades in the CPS and HC groups, respectively. Implants failed in 2.3% and 2.4% of patients in the CPS and HC groups, respectively. The incidence of cement leakage from screw augmentation was 38.9%. CONCLUSION: The CPS and HC techniques for treating osteoporotic fractures of the thoracic or lumbar spine did not differ statistically in terms of improved radiologic and clinical outcomes, final neurologic and ambulatory function, or implant failure rates, making them equally comparable alternatives.

Superior facet joint violation between open and minimally invasive techniques in lumbar fusion surgery: An updated systematic review and meta-analysis.

BACKGROUND: Superior facet joint violation (FJV) is a potential risk factor for adjacent segment disease following lumbar fusion surgery. We sought to conduct a systematic review and meta-analysis to compare screw-related superior FJV rates between the open and different minimally invasive (MI) techniques-fluoroscopy-based, 3D-image navigation, and navigation with robotic assistance-in adult lumbar fusion surgery. METHODS: We searched original articles comparing the rates of screw-related FJV between the open and different MI techniques in adult lumbar fusion surgery for lumbar degenerative diseases in PubMed, EMBASE, and the Cochrane Library from inception to September 2021. We compared the numbers of top-level pedicle screws and associated superior FJVs in the main analyses and performed subgroup analysis based on different MI techniques to examine whether individual MI approaches differed in superior FJV rate. Risk ratio (RR) and 95% confidence interval (CI) were calculated in a random-effect meta-analysis. RESULTS: Included in the meta-analysis were 16 articles with 2655 patients and 4638 top-level pedicle screws. The pooled analysis showed no significant difference in superior FJV rates between the MI and open groups (RR: 0.89, 95% CI: 0.62-1.28). The subgroup analysis demonstrated that the overall rates of superior FJV were 27.1% (411/1518) for fluoroscopy-based, 7.1% (43/603) for 3D-image navigation, and 3.2% (7/216) for navigation with robotic assistance. Compared with the open method, the overall RRs were 1.53 (95% CI: 1.19-1.96) for fluoroscopy-based, 0.41 (95% CI: 0.22-0.75) for 3D-image navigation, and 0.25 (95% CI: 0.08-0.72) for navigation with robotic assistance. CONCLUSION: Among the three common MI techniques, fluoroscopy-based can be associated with a higher risk of superior FJV, while both 3D-image navigation and navigation with robotic assistance may be associated with lower risks as compared with the open method. Considering the limitations of the study, more trials are needed to prove these clinical findings.

Outcome of Ti/PEEK Versus PEEK Cages in Minimally Invasive Transforaminal Lumbar Interbody Fusion.

STUDY DESIGN: Retrospective case-control study. OBJECTIVES: This study aims to present the clinical and radiographical outcomes of the titanium-polyetheretherketone (Ti/PEEK) composite cage compared to those of the standard PEEK cage in patients receiving minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). METHODS: Patients receiving 1 level MI-TLIF between October 2015 and October 2017 were included with a minimum of 2-year follow-up. The patients were segregated into 2 groups; Ti/PEEK group and PEEK group. Each patient was propensity-matched using preoperative age, sex, and body mass index. Early fusion rate was evaluated by computed tomography at postoperative 6 months. Clinical outcomes were assessed using the visual analog scale (VAS) and Oswestry Disability Index (ODI) scores. RESULTS: After matching, there were 27 patients included in each group. The demographics, diagnosis, and surgical details were not significantly different between the 2 groups. The 6-month rate was 88.9% in Ti/PEEK group. The fusion rate and cage subsidence rate had no difference between the 2 groups. The complication rate in the Ti/PEEK group was comparable to that in the PEEK group. There was no difference in VAS and ODI scores during a 2-year follow-up period. CONCLUSIONS: The use of Ti/PEEK composite cage was as safe and effective as the use of PEEK cage in MI-TLIF. The 6-month fusion rate was 88.9%. Our finding revealed comparable clinical results for surgeons using Ti/PEEK composite cages in MI-TLIF compared to those using the PEEK cage.

Comparing the similarity and differences in MeSH terms associated with spine-specific journals using the forest plot: A bibliometric analysis.

BACKGROUND: A common concern in the literature is the comparison of the similarities and differences between research journals, as well as the types of research they publish. At present, there are no clear methodologies that can be applied to a given article of interest. When authors use an effective and efficient method to locate journals in similar fields, they benefit greatly. By using the forest plot and major medical subject headings (MeSH terms) of Spine (Phila Pa 1976) compared to Spine J, this study: displays relatively similar journals to the target journal online and identifies the effect of the similarity odds ratio of Spine (Phila Pa 1976) compared to Spine J. METHODS: From the PubMed library, we downloaded 1000 of the most recent top 20 most similar articles related to Spine (Phila Pa 1976) and then plotted the clusters of related journals using social network analysis (SNA). The forest plot was used to compare the differences in MeSH terms for 2 journals (Spine (Phila Pa 1976) and Spine J) based on odds ratios. The heterogeneity of the data was evaluated using the Q statistic and the I-square (I2) index. RESULTS: This study shows that: the journals related to Spine (Phila Pa 1976) can easily be presented on a dashboard via Google Maps; 8 journal clusters were identified using SNA; the 3 most frequently searched MeSH terms are surgery, diagnostic imaging, and methods; and the odds ratios of MeSH terms only show significant differences with the keyword "surgery" between Spine (Phila Pa 1976) and Spine J with homogeneity at I2 = 17.7% (P = .27). CONCLUSIONS: The SNA and forest plot provide a detailed overview of the inter-journal relationships and the target journal using MeSH terms. Based on the findings of this research, readers are provided with knowledge and concept diagrams that can be used in future submissions to related journals.

Does local vancomycin powder impregnated with autogenous bone graft and bone substitute decrease the risk of deep surgical site infection in degenerative lumbar spine fusion surgery?-An ambispective study.

BACKGROUND: Deep surgical site infection (DSSI) is one of the most challenging complications in lumbar fusion surgery. Few investigations examined the effect of vancomycin powder mixed with autogenic bone graft (ABG) and bone substitutes on preventing DSSI in degenerative lumbar fusion surgeries as well as any interference with bony fusion. The aim of the study was to investigate the effects of ABG along with bone substitutes as a local vancomycin delivery system on preventing DSSI in lumbar instrumented fusion and compared with those who did not use vancomycin powder. METHODS: From January, 2015 through December, 2015, a one-year prospective study using vancomycin powder mixed with ABG and bone substitute for degenerative lumbar fusion surgeries as vancomycin (V) group, 1 gm vancomycin for 2 and 3-level, and 2 gm for more than 3-level instrumentation. From December, 2013 through December 2014, patients received degenerative lumbar fusion surgeries without using vancomycin before the vancomycin protocol were retrospectively enrolled as non-vancomycin (NV) group. Vancomycin concentration was checked at post-operative days 1 and 3 for both the serum and drainage. Patients' demographic data, microbiology reports, fusion status and functional outcomes were evaluated. RESULTS: One hundred and ten patients were enrolled prospectively in the V group, and 86 for the NV group. After an average 41 months follow-up (range, 36-54), 3 patients (3.48%) developed postoperative DSSIs in the NV group, thereby requiring revision surgeries and parenteral antibiotics treatment versus no DSSIs (0%, 0/100) in the V group. (p = 0.048). The postoperative serum vancomycin levels were undetectable and no vancomycin related side effects was encountered. The mean vancomycin concentration of drainage at postoperative days 1 and 3 were 517.96 ± 174.4 and 220.14 ± 102.3 µg/mL, respectively. At final follow-up, there was no statistical difference observed in terms of clinical and radiologic outcomes. CONCLUSIONS: Our vancomycin protocol may reduce the incidence of DSSI in degenerative lumbar fusion surgery without affecting bony fusion. LEVEL OF EVIDENCE: Level III ambispective comparative study.